/*
 * Remote VUB300 SDIO/SDmem Host Controller Driver
 *
 * Copyright (C) 2010 Elan Digital Systems Limited
 *
 * based on USB Skeleton driver - 2.2
 *
 * Copyright (C) 2001-2004 Greg Kroah-Hartman (greg@kroah.com)
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation, version 2
 *
 * VUB300: is a USB 2.0 client device with a single SDIO/SDmem/MMC slot
 *         Any SDIO/SDmem/MMC device plugged into the VUB300 will appear,
 *         by virtue of this driver, to have been plugged into a local
 *         SDIO host controller, similar to, say, a PCI Ricoh controller
 *         This is because this kernel device driver is both a USB 2.0
 *         client device driver AND an MMC host controller driver. Thus
 *         if there is an existing driver for the inserted SDIO/SDmem/MMC
 *         device then that driver will be used by the kernel to manage
 *         the device in exactly the same fashion as if it had been
 *         directly plugged into, say, a local pci bus Ricoh controller
 *
 * RANT: this driver was written using a display 128x48 - converting it
 *       to a line width of 80 makes it very difficult to support. In
 *       particular functions have been broken down into sub functions
 *       and the original meaningful names have been shortened into
 *       cryptic ones.
 *       The problem is that executing a fragment of code subject to
 *       two conditions means an indentation of 24, thus leaving only
 *       56 characters for a C statement. And that is quite ridiculous!
 *
 * Data types: data passed to/from the VUB300 is fixed to a number of
 *             bits and driver data fields reflect that limit by using
 *             u8, u16, u32
 */
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/kref.h>
#include <linux/uaccess.h>
#include <linux/usb.h>
#include <linux/mutex.h>
#include <linux/mmc/host.h>
#include <linux/mmc/card.h>
#include <linux/mmc/sdio_func.h>
#include <linux/mmc/sdio_ids.h>
#include <linux/workqueue.h>
#include <linux/ctype.h>
#include <linux/firmware.h>
#include <linux/scatterlist.h>

struct host_controller_info {
        u8 info_size;
        u16 firmware_version;
        u8 number_of_ports;
} __packed;

#define FIRMWARE_BLOCK_BOUNDARY 1024
struct sd_command_header {
        u8 header_size;
        u8 header_type;
        u8 port_number;
        u8 command_type; /* Bit7 - Rd/Wr */
        u8 command_index;
        u8 transfer_size[4]; /* ReadSize + ReadSize */
        u8 response_type;
        u8 arguments[4];
        u8 block_count[2];
        u8 block_size[2];
        u8 block_boundary[2];
        u8 reserved[44]; /* to pad out to 64 bytes */
} __packed;

struct sd_irqpoll_header {
        u8 header_size;
        u8 header_type;
        u8 port_number;
        u8 command_type; /* Bit7 - Rd/Wr */
        u8 padding[16]; /* don't ask why !! */
        u8 poll_timeout_msb;
        u8 poll_timeout_lsb;
        u8 reserved[42]; /* to pad out to 64 bytes */
} __packed;

struct sd_common_header {
        u8 header_size;
        u8 header_type;
        u8 port_number;
} __packed;

struct sd_response_header {
        u8 header_size;
        u8 header_type;
        u8 port_number;
        u8 command_type;
        u8 command_index;
        u8 command_response[0];
} __packed;

struct sd_status_header {
        u8 header_size;
        u8 header_type;
        u8 port_number;
        u16 port_flags;
        u32 sdio_clock;
        u16 host_header_size;
        u16 func_header_size;
        u16 ctrl_header_size;
} __packed;

struct sd_error_header {
        u8 header_size;
        u8 header_type;
        u8 port_number;
        u8 error_code;
} __packed;

struct sd_interrupt_header {
        u8 header_size;
        u8 header_type;
        u8 port_number;
} __packed;

struct offload_registers_access {
        u8 command_byte[4];
        u8 Respond_Byte[4];
} __packed;

#define INTERRUPT_REGISTER_ACCESSES 15
struct sd_offloaded_interrupt {
        u8 header_size;
        u8 header_type;
        u8 port_number;
        struct offload_registers_access reg[INTERRUPT_REGISTER_ACCESSES];
} __packed;

struct sd_register_header {
        u8 header_size;
        u8 header_type;
        u8 port_number;
        u8 command_type;
        u8 command_index;
        u8 command_response[6];
} __packed;

#define PIGGYBACK_REGISTER_ACCESSES 14
struct sd_offloaded_piggyback {
        struct sd_register_header sdio;
        struct offload_registers_access reg[PIGGYBACK_REGISTER_ACCESSES];
} __packed;

union sd_response {
        struct sd_common_header common;
        struct sd_status_header status;
        struct sd_error_header error;
        struct sd_interrupt_header interrupt;
        struct sd_response_header response;
        struct sd_offloaded_interrupt irq;
        struct sd_offloaded_piggyback pig;
} __packed;

union sd_command {
        struct sd_command_header head;
        struct sd_irqpoll_header poll;
} __packed;

enum SD_RESPONSE_TYPE {
        SDRT_UNSPECIFIED = 0,
        SDRT_NONE,
        SDRT_1,
        SDRT_1B,
        SDRT_2,
        SDRT_3,
        SDRT_4,
        SDRT_5,
        SDRT_5B,
        SDRT_6,
        SDRT_7,
};

#define RESPONSE_INTERRUPT                      0x01
#define RESPONSE_ERROR                          0x02
#define RESPONSE_STATUS                         0x03
#define RESPONSE_IRQ_DISABLED                   0x05
#define RESPONSE_IRQ_ENABLED                    0x06
#define RESPONSE_PIGGYBACKED                    0x07
#define RESPONSE_NO_INTERRUPT                   0x08
#define RESPONSE_PIG_DISABLED                   0x09
#define RESPONSE_PIG_ENABLED                    0x0A
#define SD_ERROR_1BIT_TIMEOUT                   0x01
#define SD_ERROR_4BIT_TIMEOUT                   0x02
#define SD_ERROR_1BIT_CRC_WRONG                 0x03
#define SD_ERROR_4BIT_CRC_WRONG                 0x04
#define SD_ERROR_1BIT_CRC_ERROR                 0x05
#define SD_ERROR_4BIT_CRC_ERROR                 0x06
#define SD_ERROR_NO_CMD_ENDBIT                  0x07
#define SD_ERROR_NO_1BIT_DATEND                 0x08
#define SD_ERROR_NO_4BIT_DATEND                 0x09
#define SD_ERROR_1BIT_UNEXPECTED_TIMEOUT        0x0A
#define SD_ERROR_4BIT_UNEXPECTED_TIMEOUT        0x0B
#define SD_ERROR_ILLEGAL_COMMAND                0x0C
#define SD_ERROR_NO_DEVICE                      0x0D
#define SD_ERROR_TRANSFER_LENGTH                0x0E
#define SD_ERROR_1BIT_DATA_TIMEOUT              0x0F
#define SD_ERROR_4BIT_DATA_TIMEOUT              0x10
#define SD_ERROR_ILLEGAL_STATE                  0x11
#define SD_ERROR_UNKNOWN_ERROR                  0x12
#define SD_ERROR_RESERVED_ERROR                 0x13
#define SD_ERROR_INVALID_FUNCTION               0x14
#define SD_ERROR_OUT_OF_RANGE                   0x15
#define SD_ERROR_STAT_CMD                       0x16
#define SD_ERROR_STAT_DATA                      0x17
#define SD_ERROR_STAT_CMD_TIMEOUT               0x18
#define SD_ERROR_SDCRDY_STUCK                   0x19
#define SD_ERROR_UNHANDLED                      0x1A
#define SD_ERROR_OVERRUN                        0x1B
#define SD_ERROR_PIO_TIMEOUT                    0x1C

#define FUN(c) (0x000007 & (c->arg>>28))
#define REG(c) (0x01FFFF & (c->arg>>9))

static bool limit_speed_to_24_MHz;
module_param(limit_speed_to_24_MHz, bool, 0644);
MODULE_PARM_DESC(limit_speed_to_24_MHz, "Limit Max SDIO Clock Speed to 24 MHz");

static bool pad_input_to_usb_pkt;
module_param(pad_input_to_usb_pkt, bool, 0644);
MODULE_PARM_DESC(pad_input_to_usb_pkt,
                 "Pad USB data input transfers to whole USB Packet");

static bool disable_offload_processing;
module_param(disable_offload_processing, bool, 0644);
MODULE_PARM_DESC(disable_offload_processing, "Disable Offload Processing");

static bool force_1_bit_data_xfers;
module_param(force_1_bit_data_xfers, bool, 0644);
MODULE_PARM_DESC(force_1_bit_data_xfers,
                 "Force SDIO Data Transfers to 1-bit Mode");

static bool force_polling_for_irqs;
module_param(force_polling_for_irqs, bool, 0644);
MODULE_PARM_DESC(force_polling_for_irqs, "Force Polling for SDIO interrupts");

static int firmware_irqpoll_timeout = 1024;
module_param(firmware_irqpoll_timeout, int, 0644);
MODULE_PARM_DESC(firmware_irqpoll_timeout, "VUB300 firmware irqpoll timeout");

static int force_max_req_size = 128;
module_param(force_max_req_size, int, 0644);
MODULE_PARM_DESC(force_max_req_size, "set max request size in kBytes");

#ifdef SMSC_DEVELOPMENT_BOARD
static int firmware_rom_wait_states = 0x04;
#else
static int firmware_rom_wait_states = 0x1C;
#endif

module_param(firmware_rom_wait_states, int, 0644);
MODULE_PARM_DESC(firmware_rom_wait_states,
                 "ROM wait states byte=RRRIIEEE (Reserved Internal External)");

#define ELAN_VENDOR_ID          0x2201
#define VUB300_VENDOR_ID        0x0424
#define VUB300_PRODUCT_ID       0x012C
static struct usb_device_id vub300_table[] = {
        {USB_DEVICE(ELAN_VENDOR_ID, VUB300_PRODUCT_ID)},
        {USB_DEVICE(VUB300_VENDOR_ID, VUB300_PRODUCT_ID)},
        {} /* Terminating entry */
};
MODULE_DEVICE_TABLE(usb, vub300_table);

static struct workqueue_struct *cmndworkqueue;
static struct workqueue_struct *pollworkqueue;
static struct workqueue_struct *deadworkqueue;

static inline int interface_to_InterfaceNumber(struct usb_interface *interface)
{
        if (!interface)
                return -1;
        if (!interface->cur_altsetting)
                return -1;
        return interface->cur_altsetting->desc.bInterfaceNumber;
}

struct sdio_register {
        unsigned func_num:3;
        unsigned sdio_reg:17;
        unsigned activate:1;
        unsigned prepared:1;
        unsigned regvalue:8;
        unsigned response:8;
        unsigned sparebit:26;
};

struct vub300_mmc_host {
        struct usb_device *udev;
        struct usb_interface *interface;
        struct kref kref;
        struct mutex cmd_mutex;
        struct mutex irq_mutex;
        char vub_name[3 + (9 * 8) + 4 + 1]; /* max of 7 sdio fn's */
        u8 cmnd_out_ep; /* EndPoint for commands */
        u8 cmnd_res_ep; /* EndPoint for responses */
        u8 data_out_ep; /* EndPoint for out data */
        u8 data_inp_ep; /* EndPoint for inp data */
        bool card_powered;
        bool card_present;
        bool read_only;
        bool large_usb_packets;
        bool app_spec; /* ApplicationSpecific */
        bool irq_enabled; /* by the MMC CORE */
        bool irq_disabled; /* in the firmware */
        unsigned bus_width:4;
        u8 total_offload_count;
        u8 dynamic_register_count;
        u8 resp_len;
        u32 datasize;
        int errors;
        int usb_transport_fail;
        int usb_timed_out;
        int irqs_queued;
        struct sdio_register sdio_register[16];
        struct offload_interrupt_function_register {
#define MAXREGBITS 4
#define MAXREGS (1<<MAXREGBITS)
#define MAXREGMASK (MAXREGS-1)
                u8 offload_count;
                u32 offload_point;
                struct offload_registers_access reg[MAXREGS];
        } fn[8];
        u16 fbs[8]; /* Function Block Size */
        struct mmc_command *cmd;
        struct mmc_request *req;
        struct mmc_data *data;
        struct mmc_host *mmc;
        struct urb *urb;
        struct urb *command_out_urb;
        struct urb *command_res_urb;
        struct completion command_complete;
        struct completion irqpoll_complete;
        union sd_command cmnd;
        union sd_response resp;
        struct timer_list sg_transfer_timer;
        struct usb_sg_request sg_request;
        struct timer_list inactivity_timer;
        struct work_struct deadwork;
        struct work_struct cmndwork;
        struct delayed_work pollwork;
        struct host_controller_info hc_info;
        struct sd_status_header system_port_status;
        u8 padded_buffer[64];
};

#define kref_to_vub300_mmc_host(d) container_of(d, struct vub300_mmc_host, kref)
#define SET_TRANSFER_PSEUDOCODE         21
#define SET_INTERRUPT_PSEUDOCODE        20
#define SET_FAILURE_MODE                18
#define SET_ROM_WAIT_STATES             16
#define SET_IRQ_ENABLE                  13
#define SET_CLOCK_SPEED                 11
#define SET_FUNCTION_BLOCK_SIZE         9
#define SET_SD_DATA_MODE                6
#define SET_SD_POWER                    4
#define ENTER_DFU_MODE                  3
#define GET_HC_INF0                     1
#define GET_SYSTEM_PORT_STATUS          0

static void vub300_delete(struct kref *kref)
{                               /* kref callback - softirq */
        struct vub300_mmc_host *vub300 = kref_to_vub300_mmc_host(kref);
        struct mmc_host *mmc = vub300->mmc;
        usb_free_urb(vub300->command_out_urb);
        vub300->command_out_urb = NULL;
        usb_free_urb(vub300->command_res_urb);
        vub300->command_res_urb = NULL;
        usb_put_dev(vub300->udev);
        mmc_free_host(mmc);
        /*
         * and hence also frees vub300
         * which is contained at the end of struct mmc
         */
}

static void vub300_queue_cmnd_work(struct vub300_mmc_host *vub300)
{
        kref_get(&vub300->kref);
        if (queue_work(cmndworkqueue, &vub300->cmndwork)) {
                /*
                 * then the cmndworkqueue was not previously
                 * running and the above get ref is obvious
                 * required and will be put when the thread
                 * terminates by a specific call
                 */
        } else {
                /*
                 * the cmndworkqueue was already running from
                 * a previous invocation and thus to keep the
                 * kref counts correct we must undo the get
                 */
                kref_put(&vub300->kref, vub300_delete);
        }
}

static void vub300_queue_poll_work(struct vub300_mmc_host *vub300, int delay)
{
        kref_get(&vub300->kref);
        if (queue_delayed_work(pollworkqueue, &vub300->pollwork, delay)) {
                /*
                 * then the pollworkqueue was not previously
                 * running and the above get ref is obvious
                 * required and will be put when the thread
                 * terminates by a specific call
                 */
        } else {
                /*
                 * the pollworkqueue was already running from
                 * a previous invocation and thus to keep the
                 * kref counts correct we must undo the get
                 */
                kref_put(&vub300->kref, vub300_delete);
        }
}

static void vub300_queue_dead_work(struct vub300_mmc_host *vub300)
{
        kref_get(&vub300->kref);
        if (queue_work(deadworkqueue, &vub300->deadwork)) {
                /*
                 * then the deadworkqueue was not previously
                 * running and the above get ref is obvious
                 * required and will be put when the thread
                 * terminates by a specific call
                 */
        } else {
                /*
                 * the deadworkqueue was already running from
                 * a previous invocation and thus to keep the
                 * kref counts correct we must undo the get
                 */
                kref_put(&vub300->kref, vub300_delete);
        }
}

static void irqpoll_res_completed(struct urb *urb)
{                               /* urb completion handler - hardirq */
        struct vub300_mmc_host *vub300 = (struct vub300_mmc_host *)urb->context;
        if (urb->status)
                vub300->usb_transport_fail = urb->status;
        complete(&vub300->irqpoll_complete);
}

static void irqpoll_out_completed(struct urb *urb)
{                               /* urb completion handler - hardirq */
        struct vub300_mmc_host *vub300 = (struct vub300_mmc_host *)urb->context;
        if (urb->status) {
                vub300->usb_transport_fail = urb->status;
                complete(&vub300->irqpoll_complete);
                return;
        } else {
                int ret;
                unsigned int pipe =
                        usb_rcvbulkpipe(vub300->udev, vub300->cmnd_res_ep);
                usb_fill_bulk_urb(vub300->command_res_urb, vub300->udev, pipe,
                                  &vub300->resp, sizeof(vub300->resp),
                                  irqpoll_res_completed, vub300);
                vub300->command_res_urb->actual_length = 0;
                ret = usb_submit_urb(vub300->command_res_urb, GFP_ATOMIC);
                if (ret) {
                        vub300->usb_transport_fail = ret;
                        complete(&vub300->irqpoll_complete);
                }
                return;
        }
}

static void send_irqpoll(struct vub300_mmc_host *vub300)
{
        /* cmd_mutex is held by vub300_pollwork_thread */
        int retval;
        int timeout = 0xFFFF & (0x0001FFFF - firmware_irqpoll_timeout);
        vub300->cmnd.poll.header_size = 22;
        vub300->cmnd.poll.header_type = 1;
        vub300->cmnd.poll.port_number = 0;
        vub300->cmnd.poll.command_type = 2;
        vub300->cmnd.poll.poll_timeout_lsb = 0xFF & (unsigned)timeout;
        vub300->cmnd.poll.poll_timeout_msb = 0xFF & (unsigned)(timeout >> 8);
        usb_fill_bulk_urb(vub300->command_out_urb, vub300->udev,
                          usb_sndbulkpipe(vub300->udev, vub300->cmnd_out_ep)
                          , &vub300->cmnd, sizeof(vub300->cmnd)
                          , irqpoll_out_completed, vub300);
        retval = usb_submit_urb(vub300->command_out_urb, GFP_KERNEL);
        if (0 > retval) {
                vub300->usb_transport_fail = retval;
                vub300_queue_poll_work(vub300, 1);
                complete(&vub300->irqpoll_complete);
                return;
        } else {
                return;
        }
}

static void new_system_port_status(struct vub300_mmc_host *vub300)
{
        int old_card_present = vub300->card_present;
        int new_card_present =
                (0x0001 & vub300->system_port_status.port_flags) ? 1 : 0;
        vub300->read_only =
                (0x0010 & vub300->system_port_status.port_flags) ? 1 : 0;
        if (new_card_present && !old_card_present) {
                dev_info(&vub300->udev->dev, "card just inserted\n");
                vub300->card_present = 1;
                vub300->bus_width = 0;
                if (disable_offload_processing)
                        strncpy(vub300->vub_name, "EMPTY Processing Disabled",
                                sizeof(vub300->vub_name));
                else
                        vub300->vub_name[0] = 0;
                mmc_detect_change(vub300->mmc, 1);
        } else if (!new_card_present && old_card_present) {
                dev_info(&vub300->udev->dev, "card just ejected\n");
                vub300->card_present = 0;
                mmc_detect_change(vub300->mmc, 0);
        } else {
                /* no change */
        }
}

static void __add_offloaded_reg_to_fifo(struct vub300_mmc_host *vub300,
                                        struct offload_registers_access
                                        *register_access, u8 func)
{
        u8 r = vub300->fn[func].offload_point + vub300->fn[func].offload_count;
        memcpy(&vub300->fn[func].reg[MAXREGMASK & r], register_access,
               sizeof(struct offload_registers_access));
        vub300->fn[func].offload_count += 1;
        vub300->total_offload_count += 1;
}

static void add_offloaded_reg(struct vub300_mmc_host *vub300,
                              struct offload_registers_access *register_access)
{
        u32 Register = ((0x03 & register_access->command_byte[0]) << 15)
                        | ((0xFF & register_access->command_byte[1]) << 7)
                        | ((0xFE & register_access->command_byte[2]) >> 1);
        u8 func = ((0x70 & register_access->command_byte[0]) >> 4);
        u8 regs = vub300->dynamic_register_count;
        u8 i = 0;
        while (0 < regs-- && 1 == vub300->sdio_register[i].activate) {
                if (vub300->sdio_register[i].func_num == func &&
                    vub300->sdio_register[i].sdio_reg == Register) {
                        if (vub300->sdio_register[i].prepared == 0)
                                vub300->sdio_register[i].prepared = 1;
                        vub300->sdio_register[i].response =
                                register_access->Respond_Byte[2];
                        vub300->sdio_register[i].regvalue =
                                register_access->Respond_Byte[3];
                        return;
                } else {
                        i += 1;
                        continue;
                }
        }
        __add_offloaded_reg_to_fifo(vub300, register_access, func);
}

static void check_vub300_port_status(struct vub300_mmc_host *vub300)
{
        /*
         * cmd_mutex is held by vub300_pollwork_thread,
         * vub300_deadwork_thread or vub300_cmndwork_thread
         */
        int retval;
        retval =
                usb_control_msg(vub300->udev, usb_rcvctrlpipe(vub300->udev, 0),
                                GET_SYSTEM_PORT_STATUS,
                                USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
                                0x0000, 0x0000, &vub300->system_port_status,
                                sizeof(vub300->system_port_status), HZ);
        if (sizeof(vub300->system_port_status) == retval)
                new_system_port_status(vub300);
}

static void __vub300_irqpoll_response(struct vub300_mmc_host *vub300)
{
        /* cmd_mutex is held by vub300_pollwork_thread */
        if (vub300->command_res_urb->actual_length == 0)
                return;

        switch (vub300->resp.common.header_type) {
        case RESPONSE_INTERRUPT:
                mutex_lock(&vub300->irq_mutex);
                if (vub300->irq_enabled)
                        mmc_signal_sdio_irq(vub300->mmc);
                else
                        vub300->irqs_queued += 1;
                vub300->irq_disabled = 1;
                mutex_unlock(&vub300->irq_mutex);
                break;
        case RESPONSE_ERROR:
                if (vub300->resp.error.error_code == SD_ERROR_NO_DEVICE)
                        check_vub300_port_status(vub300);
                break;
        case RESPONSE_STATUS:
                vub300->system_port_status = vub300->resp.status;
                new_system_port_status(vub300);
                if (!vub300->card_present)
                        vub300_queue_poll_work(vub300, HZ / 5);
                break;
        case RESPONSE_IRQ_DISABLED:
        {
                int offloaded_data_length = vub300->resp.common.header_size - 3;
                int register_count = offloaded_data_length >> 3;
                int ri = 0;
                while (register_count--) {
                        add_offloaded_reg(vub300, &vub300->resp.irq.reg[ri]);
                        ri += 1;
                }
                mutex_lock(&vub300->irq_mutex);
                if (vub300->irq_enabled)
                        mmc_signal_sdio_irq(vub300->mmc);
                else
                        vub300->irqs_queued += 1;
                vub300->irq_disabled = 1;
                mutex_unlock(&vub300->irq_mutex);
                break;
        }
        case RESPONSE_IRQ_ENABLED:
        {
                int offloaded_data_length = vub300->resp.common.header_size - 3;
                int register_count = offloaded_data_length >> 3;
                int ri = 0;
                while (register_count--) {
                        add_offloaded_reg(vub300, &vub300->resp.irq.reg[ri]);
                        ri += 1;
                }
                mutex_lock(&vub300->irq_mutex);
                if (vub300->irq_enabled)
                        mmc_signal_sdio_irq(vub300->mmc);
                else if (vub300->irqs_queued)
                        vub300->irqs_queued += 1;
                else
                        vub300->irqs_queued += 1;
                vub300->irq_disabled = 0;
                mutex_unlock(&vub300->irq_mutex);
                break;
        }
        case RESPONSE_NO_INTERRUPT:
                vub300_queue_poll_work(vub300, 1);
                break;
        default:
                break;
        }
}

static void __do_poll(struct vub300_mmc_host *vub300)
{
        /* cmd_mutex is held by vub300_pollwork_thread */
        unsigned long commretval;
        mod_timer(&vub300->inactivity_timer, jiffies + HZ);
        init_completion(&vub300->irqpoll_complete);
        send_irqpoll(vub300);
        commretval = wait_for_completion_timeout(&vub300->irqpoll_complete,
                                                 msecs_to_jiffies(500));
        if (vub300->usb_transport_fail) {
                /* no need to do anything */
        } else if (commretval == 0) {
                vub300->usb_timed_out = 1;
                usb_kill_urb(vub300->command_out_urb);
                usb_kill_urb(vub300->command_res_urb);
        } else { /* commretval > 0 */
                __vub300_irqpoll_response(vub300);
        }
}

/* this thread runs only when the driver
 * is trying to poll the device for an IRQ
 */
static void vub300_pollwork_thread(struct work_struct *work)
{                               /* NOT irq */
        struct vub300_mmc_host *vub300 = container_of(work,
                              struct vub300_mmc_host, pollwork.work);
        if (!vub300->interface) {
                kref_put(&vub300->kref, vub300_delete);
                return;
        }
        mutex_lock(&vub300->cmd_mutex);
        if (vub300->cmd) {
                vub300_queue_poll_work(vub300, 1);
        } else if (!vub300->card_present) {
                /* no need to do anything */
        } else { /* vub300->card_present */
                mutex_lock(&vub300->irq_mutex);
                if (!vub300->irq_enabled) {
                        mutex_unlock(&vub300->irq_mutex);
                } else if (vub300->irqs_queued) {
                        vub300->irqs_queued -= 1;
                        mmc_signal_sdio_irq(vub300->mmc);
                        mod_timer(&vub300->inactivity_timer, jiffies + HZ);
                        mutex_unlock(&vub300->irq_mutex);
                } else { /* NOT vub300->irqs_queued */
                        mutex_unlock(&vub300->irq_mutex);
                        __do_poll(vub300);
                }
        }
        mutex_unlock(&vub300->cmd_mutex);
        kref_put(&vub300->kref, vub300_delete);
}

static void vub300_deadwork_thread(struct work_struct *work)
{                               /* NOT irq */
        struct vub300_mmc_host *vub300 =
                container_of(work, struct vub300_mmc_host, deadwork);
        if (!vub300->interface) {
                kref_put(&vub300->kref, vub300_delete);
                return;
        }
        mutex_lock(&vub300->cmd_mutex);
        if (vub300->cmd) {
                /*
                 * a command got in as the inactivity
                 * timer expired - so we just let the
                 * processing of the command show if
                 * the device is dead
                 */
        } else if (vub300->card_present) {
                check_vub300_port_status(vub300);
        } else if (vub300->mmc && vub300->mmc->card &&
                   mmc_card_present(vub300->mmc->card)) {
                /*
                 * the MMC core must not have responded
                 * to the previous indication - lets
                 * hope that it eventually does so we
                 * will just ignore this for now
                 */
        } else {
                check_vub300_port_status(vub300);
        }
        mod_timer(&vub300->inactivity_timer, jiffies + HZ);
        mutex_unlock(&vub300->cmd_mutex);
        kref_put(&vub300->kref, vub300_delete);
}

static void vub300_inactivity_timer_expired(unsigned long data)
{                               /* softirq */
        struct vub300_mmc_host *vub300 = (struct vub300_mmc_host *)data;
        if (!vub300->interface) {
                kref_put(&vub300->kref, vub300_delete);
        } else if (vub300->cmd) {
                mod_timer(&vub300->inactivity_timer, jiffies + HZ);
        } else {
                vub300_queue_dead_work(vub300);
                mod_timer(&vub300->inactivity_timer, jiffies + HZ);
        }
}

static int vub300_response_error(u8 error_code)
{
        switch (error_code) {
        case SD_ERROR_PIO_TIMEOUT:
        case SD_ERROR_1BIT_TIMEOUT:
        case SD_ERROR_4BIT_TIMEOUT:
                return -ETIMEDOUT;
        case SD_ERROR_STAT_DATA:
        case SD_ERROR_OVERRUN:
        case SD_ERROR_STAT_CMD:
        case SD_ERROR_STAT_CMD_TIMEOUT:
        case SD_ERROR_SDCRDY_STUCK:
        case SD_ERROR_UNHANDLED:
        case SD_ERROR_1BIT_CRC_WRONG:
        case SD_ERROR_4BIT_CRC_WRONG:
        case SD_ERROR_1BIT_CRC_ERROR:
        case SD_ERROR_4BIT_CRC_ERROR:
        case SD_ERROR_NO_CMD_ENDBIT:
        case SD_ERROR_NO_1BIT_DATEND:
        case SD_ERROR_NO_4BIT_DATEND:
        case SD_ERROR_1BIT_DATA_TIMEOUT:
        case SD_ERROR_4BIT_DATA_TIMEOUT:
        case SD_ERROR_1BIT_UNEXPECTED_TIMEOUT:
        case SD_ERROR_4BIT_UNEXPECTED_TIMEOUT:
                return -EILSEQ;
        case 33:
                return -EILSEQ;
        case SD_ERROR_ILLEGAL_COMMAND:
                return -EINVAL;
        case SD_ERROR_NO_DEVICE:
                return -ENOMEDIUM;
        default:
                return -ENODEV;
        }
}

static void command_res_completed(struct urb *urb)
{                               /* urb completion handler - hardirq */
        struct vub300_mmc_host *vub300 = (struct vub300_mmc_host *)urb->context;
        if (urb->status) {
                /* we have to let the initiator handle the error */
        } else if (vub300->command_res_urb->actual_length == 0) {
                /*
                 * we have seen this happen once or twice and
                 * we suspect a buggy USB host controller
                 */
        } else if (!vub300->data) {
                /* this means that the command (typically CMD52) succeeded */
        } else if (vub300->resp.common.header_type != 0x02) {
                /*
                 * this is an error response from the VUB300 chip
                 * and we let the initiator handle it
                 */
        } else if (vub300->urb) {
                vub300->cmd->error =
                        vub300_response_error(vub300->resp.error.error_code);
                usb_unlink_urb(vub300->urb);
        } else {
                vub300->cmd->error =
                        vub300_response_error(vub300->resp.error.error_code);
                usb_sg_cancel(&vub300->sg_request);
        }
        complete(&vub300->command_complete);    /* got_response_in */
}

static void command_out_completed(struct urb *urb)
{                               /* urb completion handler - hardirq */
        struct vub300_mmc_host *vub300 = (struct vub300_mmc_host *)urb->context;
        if (urb->status) {
                complete(&vub300->command_complete);
        } else {
                int ret;
                unsigned int pipe =
                        usb_rcvbulkpipe(vub300->udev, vub300->cmnd_res_ep);
                usb_fill_bulk_urb(vub300->command_res_urb, vub300->udev, pipe,
                                  &vub300->resp, sizeof(vub300->resp),
                                  command_res_completed, vub300);
                vub300->command_res_urb->actual_length = 0;
                ret = usb_submit_urb(vub300->command_res_urb, GFP_ATOMIC);
                if (ret == 0) {
                        /*
                         * the urb completion handler will call
                         * our completion handler
                         */
                } else {
                        /*
                         * and thus we only call it directly
                         * when it will not be called
                         */
                        complete(&vub300->command_complete);
                }
        }
}

/*
 * the STUFF bits are masked out for the comparisons
 */
static void snoop_block_size_and_bus_width(struct vub300_mmc_host *vub300,
                                           u32 cmd_arg)
{
        if ((0xFBFFFE00 & cmd_arg) == 0x80022200)
                vub300->fbs[1] = (cmd_arg << 8) | (0x00FF & vub300->fbs[1]);
        else if ((0xFBFFFE00 & cmd_arg) == 0x80022000)
                vub300->fbs[1] = (0xFF & cmd_arg) | (0xFF00 & vub300->fbs[1]);
        else if ((0xFBFFFE00 & cmd_arg) == 0x80042200)
                vub300->fbs[2] = (cmd_arg << 8) | (0x00FF & vub300->fbs[2]);
        else if ((0xFBFFFE00 & cmd_arg) == 0x80042000)
                vub300->fbs[2] = (0xFF & cmd_arg) | (0xFF00 & vub300->fbs[2]);
        else if ((0xFBFFFE00 & cmd_arg) == 0x80062200)
                vub300->fbs[3] = (cmd_arg << 8) | (0x00FF & vub300->fbs[3]);
        else if ((0xFBFFFE00 & cmd_arg) == 0x80062000)
                vub300->fbs[3] = (0xFF & cmd_arg) | (0xFF00 & vub300->fbs[3]);
        else if ((0xFBFFFE00 & cmd_arg) == 0x80082200)
                vub300->fbs[4] = (cmd_arg << 8) | (0x00FF & vub300->fbs[4]);
        else if ((0xFBFFFE00 & cmd_arg) == 0x80082000)
                vub300->fbs[4] = (0xFF & cmd_arg) | (0xFF00 & vub300->fbs[4]);
        else if ((0xFBFFFE00 & cmd_arg) == 0x800A2200)
                vub300->fbs[5] = (cmd_arg << 8) | (0x00FF & vub300->fbs[5]);
        else if ((0xFBFFFE00 & cmd_arg) == 0x800A2000)
                vub300->fbs[5] = (0xFF & cmd_arg) | (0xFF00 & vub300->fbs[5]);
        else if ((0xFBFFFE00 & cmd_arg) == 0x800C2200)
                vub300->fbs[6] = (cmd_arg << 8) | (0x00FF & vub300->fbs[6]);
        else if ((0xFBFFFE00 & cmd_arg) == 0x800C2000)
                vub300->fbs[6] = (0xFF & cmd_arg) | (0xFF00 & vub300->fbs[6]);
        else if ((0xFBFFFE00 & cmd_arg) == 0x800E2200)
                vub300->fbs[7] = (cmd_arg << 8) | (0x00FF & vub300->fbs[7]);
        else if ((0xFBFFFE00 & cmd_arg) == 0x800E2000)
                vub300->fbs[7] = (0xFF & cmd_arg) | (0xFF00 & vub300->fbs[7]);
        else if ((0xFBFFFE03 & cmd_arg) == 0x80000E00)
                vub300->bus_width = 1;
        else if ((0xFBFFFE03 & cmd_arg) == 0x80000E02)
                vub300->bus_width = 4;
}

static void send_command(struct vub300_mmc_host *vub300)
{
        /* cmd_mutex is held by vub300_cmndwork_thread */
        struct mmc_command *cmd = vub300->cmd;
        struct mmc_data *data = vub300->data;
        int retval;
        int i;
        u8 response_type;
        if (vub300->app_spec) {
                switch (cmd->opcode) {
                case 6:
                        response_type = SDRT_1;
                        vub300->resp_len = 6;
                        if (0x00000000 == (0x00000003 & cmd->arg))
                                vub300->bus_width = 1;
                        else if (0x00000002 == (0x00000003 & cmd->arg))
                                vub300->bus_width = 4;
                        else
                                dev_err(&vub300->udev->dev,
                                        "unexpected ACMD6 bus_width=%d\n",
                                        0x00000003 & cmd->arg);
                        break;
                case 13:
                        response_type = SDRT_1;
                        vub300->resp_len = 6;
                        break;
                case 22:
                        response_type = SDRT_1;
                        vub300->resp_len = 6;
                        break;
                case 23:
                        response_type = SDRT_1;
                        vub300->resp_len = 6;
                        break;
                case 41:
                        response_type = SDRT_3;
                        vub300->resp_len = 6;
                        break;
                case 42:
                        response_type = SDRT_1;
                        vub300->resp_len = 6;
                        break;
                case 51:
                        response_type = SDRT_1;
                        vub300->resp_len = 6;
                        break;
                case 55:
                        response_type = SDRT_1;
                        vub300->resp_len = 6;
                        break;
                default:
                        vub300->resp_len = 0;
                        cmd->error = -EINVAL;
                        complete(&vub300->command_complete);
                        return;
                }
                vub300->app_spec = 0;
        } else {
                switch (cmd->opcode) {
                case 0:
                        response_type = SDRT_NONE;
                        vub300->resp_len = 0;
                        break;
                case 1:
                        response_type = SDRT_3;
                        vub300->resp_len = 6;
                        break;
                case 2:
                        response_type = SDRT_2;
                        vub300->resp_len = 17;
                        break;
                case 3:
                        response_type = SDRT_6;
                        vub300->resp_len = 6;
                        break;
                case 4:
                        response_type = SDRT_NONE;
                        vub300->resp_len = 0;
                        break;
                case 5:
                        response_type = SDRT_4;
                        vub300->resp_len = 6;
                        break;
                case 6:
                        response_type = SDRT_1;
                        vub300->resp_len = 6;
                        break;
                case 7:
                        response_type = SDRT_1B;
                        vub300->resp_len = 6;
                        break;
                case 8:
                        response_type = SDRT_7;
                        vub300->resp_len = 6;
                        break;
                case 9:
                        response_type = SDRT_2;
                        vub300->resp_len = 17;
                        break;
                case 10:
                        response_type = SDRT_2;
                        vub300->resp_len = 17;
                        break;
                case 12:
                        response_type = SDRT_1B;
                        vub300->resp_len = 6;
                        break;

                case 13:
                        response_type = SDRT_1;
                        vub300->resp_len = 6;
                        break;
                case 15:
                        response_type = SDRT_NONE;
                        vub300->resp_len = 0;
                        break;
                case 16:
                        for (i = 0; i < ARRAY_SIZE(vub300->fbs); i++)
                                vub300->fbs[i] = 0xFFFF & cmd->arg;
                        response_type = SDRT_1;
                        vub300->resp_len = 6;
                        break;
                case 17:
                case 18:
                case 24:
                case 25:
                case 27:
                        response_type = SDRT_1;
                        vub300->resp_len = 6;
                        break;
                case 28:
                case 29:
                        response_type = SDRT_1B;
                        vub300->resp_len = 6;
                        break;
                case 30:
                case 32:
                case 33:
                        response_type = SDRT_1;
                        vub300->resp_len = 6;
                        break;
                case 38:
                        response_type = SDRT_1B;
                        vub300->resp_len = 6;
                        break;
                case 42:
                        response_type = SDRT_1;
                        vub300->resp_len = 6;
                        break;
                case 52:
                        response_type = SDRT_5;
                        vub300->resp_len = 6;
                        snoop_block_size_and_bus_width(vub300, cmd->arg);
                        break;
                case 53:
                        response_type = SDRT_5;
                        vub300->resp_len = 6;
                        break;
                case 55:
                        response_type = SDRT_1;
                        vub300->resp_len = 6;
                        vub300->app_spec = 1;
                        break;
                case 56:
                        response_type = SDRT_1;
                        vub300->resp_len = 6;
                        break;
                default:
                        vub300->resp_len = 0;
                        cmd->error = -EINVAL;
                        complete(&vub300->command_complete);
                        return;
                }
        }
        /*
         * it is a shame that we can not use "sizeof(struct sd_command_header)"
         * this is because the packet _must_ be padded to 64 bytes
         */
        vub300->cmnd.head.header_size = 20;
        vub300->cmnd.head.header_type = 0x00;
        vub300->cmnd.head.port_number = 0; /* "0" means port 1 */
        vub300->cmnd.head.command_type = 0x00; /* standard read command */
        vub300->cmnd.head.response_type = response_type;
        vub300->cmnd.head.command_index = cmd->opcode;
        vub300->cmnd.head.arguments[0] = cmd->arg >> 24;
        vub300->cmnd.head.arguments[1] = cmd->arg >> 16;
        vub300->cmnd.head.arguments[2] = cmd->arg >> 8;
        vub300->cmnd.head.arguments[3] = cmd->arg >> 0;
        if (cmd->opcode == 52) {
                int fn = 0x7 & (cmd->arg >> 28);
                vub300->cmnd.head.block_count[0] = 0;
                vub300->cmnd.head.block_count[1] = 0;
                vub300->cmnd.head.block_size[0] = (vub300->fbs[fn] >> 8) & 0xFF;
                vub300->cmnd.head.block_size[1] = (vub300->fbs[fn] >> 0) & 0xFF;
                vub300->cmnd.head.command_type = 0x00;
                vub300->cmnd.head.transfer_size[0] = 0;
                vub300->cmnd.head.transfer_size[1] = 0;
                vub300->cmnd.head.transfer_size[2] = 0;
                vub300->cmnd.head.transfer_size[3] = 0;
        } else if (!data) {
                vub300->cmnd.head.block_count[0] = 0;
                vub300->cmnd.head.block_count[1] = 0;
                vub300->cmnd.head.block_size[0] = (vub300->fbs[0] >> 8) & 0xFF;
                vub300->cmnd.head.block_size[1] = (vub300->fbs[0] >> 0) & 0xFF;
                vub300->cmnd.head.command_type = 0x00;
                vub300->cmnd.head.transfer_size[0] = 0;
                vub300->cmnd.head.transfer_size[1] = 0;
                vub300->cmnd.head.transfer_size[2] = 0;
                vub300->cmnd.head.transfer_size[3] = 0;
        } else if (cmd->opcode == 53) {
                int fn = 0x7 & (cmd->arg >> 28);
                if (0x08 & vub300->cmnd.head.arguments[0]) { /* BLOCK MODE */
                        vub300->cmnd.head.block_count[0] =
                                (data->blocks >> 8) & 0xFF;
                        vub300->cmnd.head.block_count[1] =
                                (data->blocks >> 0) & 0xFF;
                        vub300->cmnd.head.block_size[0] =
                                (data->blksz >> 8) & 0xFF;
                        vub300->cmnd.head.block_size[1] =
                                (data->blksz >> 0) & 0xFF;
                } else {        /* BYTE MODE */
                        vub300->cmnd.head.block_count[0] = 0;
                        vub300->cmnd.head.block_count[1] = 0;
                        vub300->cmnd.head.block_size[0] =
                                (vub300->datasize >> 8) & 0xFF;
                        vub300->cmnd.head.block_size[1] =
                                (vub300->datasize >> 0) & 0xFF;
                }
                vub300->cmnd.head.command_type =
                        (MMC_DATA_READ & data->flags) ? 0x00 : 0x80;
                vub300->cmnd.head.transfer_size[0] =
                        (vub300->datasize >> 24) & 0xFF;
                vub300->cmnd.head.transfer_size[1] =
                        (vub300->datasize >> 16) & 0xFF;
                vub300->cmnd.head.transfer_size[2] =
                        (vub300->datasize >> 8) & 0xFF;
                vub300->cmnd.head.transfer_size[3] =
                        (vub300->datasize >> 0) & 0xFF;
                if (vub300->datasize < vub300->fbs[fn]) {
                        vub300->cmnd.head.block_count[0] = 0;
                        vub300->cmnd.head.block_count[1] = 0;
                }
        } else {
                vub300->cmnd.head.block_count[0] = (data->blocks >> 8) & 0xFF;
                vub300->cmnd.head.block_count[1] = (data->blocks >> 0) & 0xFF;
                vub300->cmnd.head.block_size[0] = (data->blksz >> 8) & 0xFF;
                vub300->cmnd.head.block_size[1] = (data->blksz >> 0) & 0xFF;
                vub300->cmnd.head.command_type =
                        (MMC_DATA_READ & data->flags) ? 0x00 : 0x80;
                vub300->cmnd.head.transfer_size[0] =
                        (vub300->datasize >> 24) & 0xFF;
                vub300->cmnd.head.transfer_size[1] =
                        (vub300->datasize >> 16) & 0xFF;
                vub300->cmnd.head.transfer_size[2] =
                        (vub300->datasize >> 8) & 0xFF;
                vub300->cmnd.head.transfer_size[3] =
                        (vub300->datasize >> 0) & 0xFF;
                if (vub300->datasize < vub300->fbs[0]) {
                        vub300->cmnd.head.block_count[0] = 0;
                        vub300->cmnd.head.block_count[1] = 0;
                }
        }
        if (vub300->cmnd.head.block_size[0] || vub300->cmnd.head.block_size[1]) {
                u16 block_size = vub300->cmnd.head.block_size[1] |
                        (vub300->cmnd.head.block_size[0] << 8);
                u16 block_boundary = FIRMWARE_BLOCK_BOUNDARY -
                        (FIRMWARE_BLOCK_BOUNDARY % block_size);
                vub300->cmnd.head.block_boundary[0] =
                        (block_boundary >> 8) & 0xFF;
                vub300->cmnd.head.block_boundary[1] =
                        (block_boundary >> 0) & 0xFF;
        } else {
                vub300->cmnd.head.block_boundary[0] = 0;
                vub300->cmnd.head.block_boundary[1] = 0;
        }
        usb_fill_bulk_urb(vub300->command_out_urb, vub300->udev,
                          usb_sndbulkpipe(vub300->udev, vub300->cmnd_out_ep),
                          &vub300->cmnd, sizeof(vub300->cmnd),
                          command_out_completed, vub300);
        retval = usb_submit_urb(vub300->command_out_urb, GFP_KERNEL);
        if (retval < 0) {
                cmd->error = retval;
                complete(&vub300->command_complete);
                return;
        } else {
                return;
        }
}

/*
 * timer callback runs in atomic mode
 *       so it cannot call usb_kill_urb()
 */
static void vub300_sg_timed_out(unsigned long data)
{
        struct vub300_mmc_host *vub300 = (struct vub300_mmc_host *)data;
        vub300->usb_timed_out = 1;
        usb_sg_cancel(&vub300->sg_request);
        usb_unlink_urb(vub300->command_out_urb);
        usb_unlink_urb(vub300->command_res_urb);
}

static u16 roundup_to_multiple_of_64(u16 number)
{
        return 0xFFC0 & (0x3F + number);
}

/*
 * this is a separate function to solve the 80 column width restriction
 */
static void __download_offload_pseudocode(struct vub300_mmc_host *vub300,
                                          const struct firmware *fw)
{
        u8 register_count = 0;
        u16 ts = 0;
        u16 interrupt_size = 0;
        const u8 *data = fw->data;
        int size = fw->size;
        u8 c;
        dev_info(&vub300->udev->dev, "using %s for SDIO offload processing\n",
                 vub300->vub_name);
        do {
                c = *data++;
        } while (size-- && c); /* skip comment */
        dev_info(&vub300->udev->dev, "using offload firmware %s %s\n", fw->data,
                 vub300->vub_name);
        if (size < 4) {
                dev_err(&vub300->udev->dev,
                        "corrupt offload pseudocode in firmware %s\n",
                        vub300->vub_name);
                strncpy(vub300->vub_name, "corrupt offload pseudocode",
                        sizeof(vub300->vub_name));
                return;
        }
        interrupt_size += *data++;
        size -= 1;
        interrupt_size <<= 8;
        interrupt_size += *data++;
        size -= 1;
        if (interrupt_size < size) {
                u16 xfer_length = roundup_to_multiple_of_64(interrupt_size);
                u8 *xfer_buffer = kmalloc(xfer_length, GFP_KERNEL);
                if (xfer_buffer) {
                        int retval;
                        memcpy(xfer_buffer, data, interrupt_size);
                        memset(xfer_buffer + interrupt_size, 0,
                               xfer_length - interrupt_size);
                        size -= interrupt_size;
                        data += interrupt_size;
                        retval =
                                usb_control_msg(vub300->udev,
                                                usb_sndctrlpipe(vub300->udev, 0),
                                                SET_INTERRUPT_PSEUDOCODE,
                                                USB_DIR_OUT | USB_TYPE_VENDOR |
                                                USB_RECIP_DEVICE, 0x0000, 0x0000,
                                                xfer_buffer, xfer_length, HZ);
                        kfree(xfer_buffer);
                        if (retval < 0) {
                                strncpy(vub300->vub_name,
                                        "SDIO pseudocode download failed",
                                        sizeof(vub300->vub_name));
                                return;
                        }
                } else {
                        dev_err(&vub300->udev->dev,
                                "not enough memory for xfer buffer to send"
                                " INTERRUPT_PSEUDOCODE for %s %s\n", fw->data,
                                vub300->vub_name);
                        strncpy(vub300->vub_name,
                                "SDIO interrupt pseudocode download failed",
                                sizeof(vub300->vub_name));
                        return;
                }
        } else {
                dev_err(&vub300->udev->dev,
                        "corrupt interrupt pseudocode in firmware %s %s\n",
                        fw->data, vub300->vub_name);
                strncpy(vub300->vub_name, "corrupt interrupt pseudocode",
                        sizeof(vub300->vub_name));
                return;
        }
        ts += *data++;
        size -= 1;
        ts <<= 8;
        ts += *data++;
        size -= 1;
        if (ts < size) {
                u16 xfer_length = roundup_to_multiple_of_64(ts);
                u8 *xfer_buffer = kmalloc(xfer_length, GFP_KERNEL);
                if (xfer_buffer) {
                        int retval;
                        memcpy(xfer_buffer, data, ts);
                        memset(xfer_buffer + ts, 0,
                               xfer_length - ts);
                        size -= ts;
                        data += ts;
                        retval =
                                usb_control_msg(vub300->udev,
                                                usb_sndctrlpipe(vub300->udev, 0),
                                                SET_TRANSFER_PSEUDOCODE,
                                                USB_DIR_OUT | USB_TYPE_VENDOR |
                                                USB_RECIP_DEVICE, 0x0000, 0x0000,
                                                xfer_buffer, xfer_length, HZ);
                        kfree(xfer_buffer);
                        if (retval < 0) {
                                strncpy(vub300->vub_name,
                                        "SDIO pseudocode download failed",
                                        sizeof(vub300->vub_name));
                                return;
                        }
                } else {
                        dev_err(&vub300->udev->dev,
                                "not enough memory for xfer buffer to send"
                                " TRANSFER_PSEUDOCODE for %s %s\n", fw->data,
                                vub300->vub_name);
                        strncpy(vub300->vub_name,
                                "SDIO transfer pseudocode download failed",
                                sizeof(vub300->vub_name));
                        return;
                }
        } else {
                dev_err(&vub300->udev->dev,
                        "corrupt transfer pseudocode in firmware %s %s\n",
                        fw->data, vub300->vub_name);
                strncpy(vub300->vub_name, "corrupt transfer pseudocode",
                        sizeof(vub300->vub_name));
                return;
        }
        register_count += *data++;
        size -= 1;
        if (register_count * 4 == size) {
                int I = vub300->dynamic_register_count = register_count;
                int i = 0;
                while (I--) {
                        unsigned int func_num = 0;
                        vub300->sdio_register[i].func_num = *data++;
                        size -= 1;
                        func_num += *data++;
                        size -= 1;
                        func_num <<= 8;
                        func_num += *data++;
                        size -= 1;
                        func_num <<= 8;
                        func_num += *data++;
                        size -= 1;
                        vub300->sdio_register[i].sdio_reg = func_num;
                        vub300->sdio_register[i].activate = 1;
                        vub300->sdio_register[i].prepared = 0;
                        i += 1;
                }
                dev_info(&vub300->udev->dev,
                         "initialized %d dynamic pseudocode registers\n",
                         vub300->dynamic_register_count);
                return;
        } else {
                dev_err(&vub300->udev->dev,
                        "corrupt dynamic registers in firmware %s\n",
                        vub300->vub_name);
                strncpy(vub300->vub_name, "corrupt dynamic registers",
                        sizeof(vub300->vub_name));
                return;
        }
}

/*
 * if the binary containing the EMPTY PseudoCode can not be found
 * vub300->vub_name is set anyway in order to prevent an automatic retry
 */
static void download_offload_pseudocode(struct vub300_mmc_host *vub300)
{
        struct mmc_card *card = vub300->mmc->card;
        int sdio_funcs = card->sdio_funcs;
        const struct firmware *fw = NULL;
        int l = snprintf(vub300->vub_name, sizeof(vub300->vub_name),
                         "vub_%04X%04X", card->cis.vendor, card->cis.device);
        int n = 0;
        int retval;
        for (n = 0; n < sdio_funcs; n++) {
                struct sdio_func *sf = card->sdio_func[n];
                l += snprintf(vub300->vub_name + l,
                              sizeof(vub300->vub_name) - l, "_%04X%04X",
                              sf->vendor, sf->device);
        }
        snprintf(vub300->vub_name + l, sizeof(vub300->vub_name) - l, ".bin");
        dev_info(&vub300->udev->dev, "requesting offload firmware %s\n",
                 vub300->vub_name);
        retval = request_firmware(&fw, vub300->vub_name, &card->dev);
        if (retval < 0) {
                strncpy(vub300->vub_name, "vub_default.bin",
                        sizeof(vub300->vub_name));
                retval = request_firmware(&fw, vub300->vub_name, &card->dev);
                if (retval < 0) {
                        strncpy(vub300->vub_name,
                                "no SDIO offload firmware found",
                                sizeof(vub300->vub_name));
                } else {
                        __download_offload_pseudocode(vub300, fw);
                        release_firmware(fw);
                }
        } else {
                __download_offload_pseudocode(vub300, fw);
                release_firmware(fw);
        }
}

static void vub300_usb_bulk_msg_completion(struct urb *urb)
{                               /* urb completion handler - hardirq */
        complete((struct completion *)urb->context);
}

static int vub300_usb_bulk_msg(struct vub300_mmc_host *vub300,
                               unsigned int pipe, void *data, int len,
                               int *actual_length, int timeout_msecs)
{
        /* cmd_mutex is held by vub300_cmndwork_thread */
        struct usb_device *usb_dev = vub300->udev;
        struct completion done;
        int retval;
        vub300->urb = usb_alloc_urb(0, GFP_KERNEL);
        if (!vub300->urb)
                return -ENOMEM;
        usb_fill_bulk_urb(vub300->urb, usb_dev, pipe, data, len,
                          vub300_usb_bulk_msg_completion, NULL);
        init_completion(&done);
        vub300->urb->context = &done;
        vub300->urb->actual_length = 0;
        retval = usb_submit_urb(vub300->urb, GFP_KERNEL);
        if (unlikely(retval))
                goto out;
        if (!wait_for_completion_timeout
            (&done, msecs_to_jiffies(timeout_msecs))) {
                retval = -ETIMEDOUT;
                usb_kill_urb(vub300->urb);
        } else {
                retval = vub300->urb->status;
        }
out:
        *actual_length = vub300->urb->actual_length;
        usb_free_urb(vub300->urb);
        vub300->urb = NULL;
        return retval;
}

static int __command_read_data(struct vub300_mmc_host *vub300,
                               struct mmc_command *cmd, struct mmc_data *data)
{
        /* cmd_mutex is held by vub300_cmndwork_thread */
        int linear_length = vub300->datasize;
        int padded_length = vub300->large_usb_packets ?
                ((511 + linear_length) >> 9) << 9 :
                ((63 + linear_length) >> 6) << 6;
        if ((padded_length == linear_length) || !pad_input_to_usb_pkt) {
                int result;
                unsigned pipe;
                pipe = usb_rcvbulkpipe(vub300->udev, vub300->data_inp_ep);
                result = usb_sg_init(&vub300->sg_request, vub300->udev,
                                     pipe, 0, data->sg,
                                     data->sg_len, 0, GFP_KERNEL);
                if (result < 0) {
                        usb_unlink_urb(vub300->command_out_urb);
                        usb_unlink_urb(vub300->command_res_urb);
                        cmd->error = result;
                        data->bytes_xfered = 0;
                        return 0;
                } else {
                        vub300->sg_transfer_timer.expires =
                                jiffies + msecs_to_jiffies(2000 +
                                                  (linear_length / 16384));
                        add_timer(&vub300->sg_transfer_timer);
                        usb_sg_wait(&vub300->sg_request);
                        del_timer(&vub300->sg_transfer_timer);
                        if (vub300->sg_request.status < 0) {
                                cmd->error = vub300->sg_request.status;
                                data->bytes_xfered = 0;
                                return 0;
                        } else {
                                data->bytes_xfered = vub300->datasize;
                                return linear_length;
                        }
                }
        } else {
                u8 *buf = kmalloc(padded_length, GFP_KERNEL);
                if (buf) {
                        int result;
                        unsigned pipe = usb_rcvbulkpipe(vub300->udev,
                                                        vub300->data_inp_ep);
                        int actual_length = 0;
                        result = vub300_usb_bulk_msg(vub300, pipe, buf,
                                             padded_length, &actual_length,
                                             2000 + (padded_length / 16384));
                        if (result < 0) {
                                cmd->error = result;
                                data->bytes_xfered = 0;
                                kfree(buf);
                                return 0;
                        } else if (actual_length < linear_length) {
                                cmd->error = -EREMOTEIO;
                                data->bytes_xfered = 0;
                                kfree(buf);
                                return 0;
                        } else {
                                sg_copy_from_buffer(data->sg, data->sg_len, buf,
                                                    linear_length);
                                kfree(buf);
                                data->bytes_xfered = vub300->datasize;
                                return linear_length;
                        }
                } else {
                        cmd->error = -ENOMEM;
                        data->bytes_xfered = 0;
                        return 0;
                }
        }
}

static int __command_write_data(struct vub300_mmc_host *vub300,
                                struct mmc_command *cmd, struct mmc_data *data)
{
        /* cmd_mutex is held by vub300_cmndwork_thread */
        unsigned pipe = usb_sndbulkpipe(vub300->udev, vub300->data_out_ep);
        int linear_length = vub300->datasize;
        int modulo_64_length = linear_length & 0x003F;
        int modulo_512_length = linear_length & 0x01FF;
        if (linear_length < 64) {
                int result;
                int actual_length;
                sg_copy_to_buffer(data->sg, data->sg_len,
                                  vub300->padded_buffer,
                                  sizeof(vub300->padded_buffer));
                memset(vub300->padded_buffer + linear_length, 0,
                       sizeof(vub300->padded_buffer) - linear_length);
                result = vub300_usb_bulk_msg(vub300, pipe, vub300->padded_buffer,
                                             sizeof(vub300->padded_buffer),
                                             &actual_length, 2000 +
                                             (sizeof(vub300->padded_buffer) /
                                              16384));
                if (result < 0) {
                        cmd->error = result;
                        data->bytes_xfered = 0;
                } else {
                        data->bytes_xfered = vub300->datasize;
                }
        } else if ((!vub300->large_usb_packets && (0 < modulo_64_length)) ||
                    (vub300->large_usb_packets && (64 > modulo_512_length))
                ) {             /* don't you just love these work-rounds */
                int padded_length = ((63 + linear_length) >> 6) << 6;
                u8 *buf = kmalloc(padded_length, GFP_KERNEL);
                if (buf) {
                        int result;
                        int actual_length;
                        sg_copy_to_buffer(data->sg, data->sg_len, buf,
                                          padded_length);
                        memset(buf + linear_length, 0,
                               padded_length - linear_length);
                        result =
                                vub300_usb_bulk_msg(vub300, pipe, buf,
                                                    padded_length, &actual_length,
                                                    2000 + padded_length / 16384);
                        kfree(buf);
                        if (result < 0) {
                                cmd->error = result;
                                data->bytes_xfered = 0;
                        } else {
                                data->bytes_xfered = vub300->datasize;
                        }
                } else {
                        cmd->error = -ENOMEM;
                        data->bytes_xfered = 0;
                }
        } else {                /* no data padding required */
                int result;
                unsigned char buf[64 * 4];
                sg_copy_to_buffer(data->sg, data->sg_len, buf, sizeof(buf));
                result = usb_sg_init(&vub300->sg_request, vub300->udev,
                                     pipe, 0, data->sg,
                                     data->sg_len, 0, GFP_KERNEL);
                if (result < 0) {
                        usb_unlink_urb(vub300->command_out_urb);
                        usb_unlink_urb(vub300->command_res_urb);
                        cmd->error = result;
                        data->bytes_xfered = 0;
                } else {
                        vub300->sg_transfer_timer.expires =
                                jiffies + msecs_to_jiffies(2000 +
                                                           linear_length / 16384);
                        add_timer(&vub300->sg_transfer_timer);
                        usb_sg_wait(&vub300->sg_request);
                        if (cmd->error) {
                                data->bytes_xfered = 0;
                        } else {
                                del_timer(&vub300->sg_transfer_timer);
                                if (vub300->sg_request.status < 0) {
                                        cmd->error = vub300->sg_request.status;
                                        data->bytes_xfered = 0;
                                } else {
                                        data->bytes_xfered = vub300->datasize;
                                }
                        }
                }
        }
        return linear_length;
}

static void __vub300_command_response(struct vub300_mmc_host *vub300,
                                      struct mmc_command *cmd,
                                      struct mmc_data *data, int data_length)
{
        /* cmd_mutex is held by vub300_cmndwork_thread */
        long respretval;
        int msec_timeout = 1000 + data_length / 4;
        respretval =
                wait_for_completion_timeout(&vub300->command_complete,
                                            msecs_to_jiffies(msec_timeout));
        if (respretval == 0) { /* TIMED OUT */
                /* we don't know which of "out" and "res" if any failed */
                int result;
                vub300->usb_timed_out = 1;
                usb_kill_urb(vub300->command_out_urb);
                usb_kill_urb(vub300->command_res_urb);
                cmd->error = -ETIMEDOUT;
                result = usb_lock_device_for_reset(vub300->udev,
                                                   vub300->interface);
                if (result == 0) {
                        result = usb_reset_device(vub300->udev);
                        usb_unlock_device(vub300->udev);
                }
        } else if (respretval < 0) {
                /* we don't know which of "out" and "res" if any failed */
                usb_kill_urb(vub300->command_out_urb);
                usb_kill_urb(vub300->command_res_urb);
                cmd->error = respretval;
        } else if (cmd->error) {
                /*
                 * the error occurred sending the command
                 * or receiving the response
                 */
        } else if (vub300->command_out_urb->status) {
                vub300->usb_transport_fail = vub300->command_out_urb->status;
                cmd->error = -EPROTO == vub300->command_out_urb->status ?
                        -ESHUTDOWN : vub300->command_out_urb->status;
        } else if (vub300->command_res_urb->status) {
                vub300->usb_transport_fail = vub300->command_res_urb->status;
                cmd->error = -EPROTO == vub300->command_res_urb->status ?
                        -ESHUTDOWN : vub300->command_res_urb->status;
        } else if (vub300->resp.common.header_type == 0x00) {
                /*
                 * the command completed successfully
                 * and there was no piggybacked data
                 */
        } else if (vub300->resp.common.header_type == RESPONSE_ERROR) {
                cmd->error =
                        vub300_response_error(vub300->resp.error.error_code);
                if (vub300->data)
                        usb_sg_cancel(&vub300->sg_request);
        } else if (vub300->resp.common.header_type == RESPONSE_PIGGYBACKED) {
                int offloaded_data_length =
                        vub300->resp.common.header_size -
                        sizeof(struct sd_register_header);
                int register_count = offloaded_data_length >> 3;
                int ri = 0;
                while (register_count--) {
                        add_offloaded_reg(vub300, &vub300->resp.pig.reg[ri]);
                        ri += 1;
                }
                vub300->resp.common.header_size =
                        sizeof(struct sd_register_header);
                vub300->resp.common.header_type = 0x00;
                cmd->error = 0;
        } else if (vub300->resp.common.header_type == RESPONSE_PIG_DISABLED) {
                int offloaded_data_length =
                        vub300->resp.common.header_size -
                        sizeof(struct sd_register_header);
                int register_count = offloaded_data_length >> 3;
                int ri = 0;
                while (register_count--) {
                        add_offloaded_reg(vub300, &vub300->resp.pig.reg[ri]);
                        ri += 1;
                }
                mutex_lock(&vub300->irq_mutex);
                if (vub300->irqs_queued) {
                        vub300->irqs_queued += 1;
                } else if (vub300->irq_enabled) {
                        vub300->irqs_queued += 1;
                        vub300_queue_poll_work(vub300, 0);
                } else {
                        vub300->irqs_queued += 1;
                }
                vub300->irq_disabled = 1;
                mutex_unlock(&vub300->irq_mutex);
                vub300->resp.common.header_size =
                        sizeof(struct sd_register_header);
                vub300->resp.common.header_type = 0x00;
                cmd->error = 0;
        } else if (vub300->resp.common.header_type == RESPONSE_PIG_ENABLED) {
                int offloaded_data_length =
                        vub300->resp.common.header_size -
                        sizeof(struct sd_register_header);
                int register_count = offloaded_data_length >> 3;
                int ri = 0;
                while (register_count--) {
                        add_offloaded_reg(vub300, &vub300->resp.pig.reg[ri]);
                        ri += 1;
                }
                mutex_lock(&vub300->irq_mutex);
                if (vub300->irqs_queued) {
                        vub300->irqs_queued += 1;
                } else if (vub300->irq_enabled) {
                        vub300->irqs_queued += 1;
                        vub300_queue_poll_work(vub300, 0);
                } else {
                        vub300->irqs_queued += 1;
                }
                vub300->irq_disabled = 0;
                mutex_unlock(&vub300->irq_mutex);
                vub300->resp.common.header_size =
                        sizeof(struct sd_register_header);
                vub300->resp.common.header_type = 0x00;
                cmd->error = 0;
        } else {
                cmd->error = -EINVAL;
        }
}

static void construct_request_response(struct vub300_mmc_host *vub300,
                                       struct mmc_command *cmd)
{
        int resp_len = vub300->resp_len;
        int less_cmd = (17 == resp_len) ? resp_len : resp_len - 1;
        int bytes = 3 & less_cmd;
        int words = less_cmd >> 2;
        u8 *r = vub300->resp.response.command_response;
        if (bytes == 3) {
                cmd->resp[words] = (r[1 + (words << 2)] << 24)
                        | (r[2 + (words << 2)] << 16)
                        | (r[3 + (words << 2)] << 8);
        } else if (bytes == 2) {
                cmd->resp[words] = (r[1 + (words << 2)] << 24)
                        | (r[2 + (words << 2)] << 16);
        } else if (bytes == 1) {
                cmd->resp[words] = (r[1 + (words << 2)] << 24);
        }
        while (words-- > 0) {
                cmd->resp[words] = (r[1 + (words << 2)] << 24)
                        | (r[2 + (words << 2)] << 16)
                        | (r[3 + (words << 2)] << 8)
                        | (r[4 + (words << 2)] << 0);
        }
        if ((cmd->opcode == 53) && (0x000000FF & cmd->resp[0]))
                cmd->resp[0] &= 0xFFFFFF00;
}

/* this thread runs only when there is an upper level command req outstanding */
static void vub300_cmndwork_thread(struct work_struct *work)
{
        struct vub300_mmc_host *vub300 =
                container_of(work, struct vub300_mmc_host, cmndwork);
        if (!vub300->interface) {
                kref_put(&vub300->kref, vub300_delete);
                return;
        } else {
                struct mmc_request *req = vub300->req;
                struct mmc_command *cmd = vub300->cmd;
                struct mmc_data *data = vub300->data;
                int data_length;
                mutex_lock(&vub300->cmd_mutex);
                init_completion(&vub300->command_complete);
                if (likely(vub300->vub_name[0]) || !vub300->mmc->card ||
                    !mmc_card_present(vub300->mmc->card)) {
                        /*
                         * the name of the EMPTY Pseudo firmware file
                         * is used as a flag to indicate that the file
                         * has been already downloaded to the VUB300 chip
                         */
                } else if (0 == vub300->mmc->card->sdio_funcs) {
                        strncpy(vub300->vub_name, "SD memory device",
                                sizeof(vub300->vub_name));
                } else {
                        download_offload_pseudocode(vub300);
                }
                send_command(vub300);
                if (!data)
                        data_length = 0;
                else if (MMC_DATA_READ & data->flags)
                        data_length = __command_read_data(vub300, cmd, data);
                else
                        data_length = __command_write_data(vub300, cmd, data);
                __vub300_command_response(vub300, cmd, data, data_length);
                vub300->req = NULL;
                vub300->cmd = NULL;
                vub300->data = NULL;
                if (cmd->error) {
                        if (cmd->error == -ENOMEDIUM)
                                check_vub300_port_status(vub300);
                        mutex_unlock(&vub300->cmd_mutex);
                        mmc_request_done(vub300->mmc, req);
                        kref_put(&vub300->kref, vub300_delete);
                        return;
                } else {
                        construct_request_response(vub300, cmd);
                        vub300->resp_len = 0;
                        mutex_unlock(&vub300->cmd_mutex);
                        kref_put(&vub300->kref, vub300_delete);
                        mmc_request_done(vub300->mmc, req);
                        return;
                }
        }
}

static int examine_cyclic_buffer(struct vub300_mmc_host *vub300,
                                 struct mmc_command *cmd, u8 Function)
{
        /* cmd_mutex is held by vub300_mmc_request */
        u8 cmd0 = 0xFF & (cmd->arg >> 24);
        u8 cmd1 = 0xFF & (cmd->arg >> 16);
        u8 cmd2 = 0xFF & (cmd->arg >> 8);
        u8 cmd3 = 0xFF & (cmd->arg >> 0);
        int first = MAXREGMASK & vub300->fn[Function].offload_point;
        struct offload_registers_access *rf = &vub300->fn[Function].reg[first];
        if (cmd0 == rf->command_byte[0] &&
            cmd1 == rf->command_byte[1] &&
            cmd2 == rf->command_byte[2] &&
            cmd3 == rf->command_byte[3]) {
                u8 checksum = 0x00;
                cmd->resp[1] = checksum << 24;
                cmd->resp[0] = (rf->Respond_Byte[0] << 24)
                        | (rf->Respond_Byte[1] << 16)
                        | (rf->Respond_Byte[2] << 8)
                        | (rf->Respond_Byte[3] << 0);
                vub300->fn[Function].offload_point += 1;
                vub300->fn[Function].offload_count -= 1;
                vub300->total_offload_count -= 1;
                return 1;
        } else {
                int delta = 1;  /* because it does not match the first one */
                u8 register_count = vub300->fn[Function].offload_count - 1;
                u32 register_point = vub300->fn[Function].offload_point + 1;
                while (0 < register_count) {
                        int point = MAXREGMASK & register_point;
                        struct offload_registers_access *r =
                                &vub300->fn[Function].reg[point];
                        if (cmd0 == r->command_byte[0] &&
                            cmd1 == r->command_byte[1] &&
                            cmd2 == r->command_byte[2] &&
                            cmd3 == r->command_byte[3]) {
                                u8 checksum = 0x00;
                                cmd->resp[1] = checksum << 24;
                                cmd->resp[0] = (r->Respond_Byte[0] << 24)
                                        | (r->Respond_Byte[1] << 16)
                                        | (r->Respond_Byte[2] << 8)
                                        | (r->Respond_Byte[3] << 0);
                                vub300->fn[Function].offload_point += delta;
                                vub300->fn[Function].offload_count -= delta;
                                vub300->total_offload_count -= delta;
                                return 1;
                        } else {
                                register_point += 1;
                                register_count -= 1;
                                delta += 1;
                                continue;
                        }
                }
                return 0;
        }
}

static int satisfy_request_from_offloaded_data(struct vub300_mmc_host *vub300,
                                               struct mmc_command *cmd)
{
        /* cmd_mutex is held by vub300_mmc_request */
        u8 regs = vub300->dynamic_register_count;
        u8 i = 0;
        u8 func = FUN(cmd);
        u32 reg = REG(cmd);
        while (0 < regs--) {
                if ((vub300->sdio_register[i].func_num == func) &&
                    (vub300->sdio_register[i].sdio_reg == reg)) {
                        if (!vub300->sdio_register[i].prepared) {
                                return 0;
                        } else if ((0x80000000 & cmd->arg) == 0x80000000) {
                                /*
                                 * a write to a dynamic register
                                 * nullifies our offloaded value
                                 */
                                vub300->sdio_register[i].prepared = 0;
                                return 0;
                        } else {
                                u8 checksum = 0x00;
                                u8 rsp0 = 0x00;
                                u8 rsp1 = 0x00;
                                u8 rsp2 = vub300->sdio_register[i].response;
                                u8 rsp3 = vub300->sdio_register[i].regvalue;
                                vub300->sdio_register[i].prepared = 0;
                                cmd->resp[1] = checksum << 24;
                                cmd->resp[0] = (rsp0 << 24)
                                        | (rsp1 << 16)
                                        | (rsp2 << 8)
                                        | (rsp3 << 0);
                                return 1;
                        }
                } else {
                        i += 1;
                        continue;
                }
        }
        if (vub300->total_offload_count == 0)
                return 0;
        else if (vub300->fn[func].offload_count == 0)
                return 0;
        else
                return examine_cyclic_buffer(vub300, cmd, func);
}

static void vub300_mmc_request(struct mmc_host *mmc, struct mmc_request *req)
{                               /* NOT irq */
        struct mmc_command *cmd = req->cmd;
        struct vub300_mmc_host *vub300 = mmc_priv(mmc);
        if (!vub300->interface) {
                cmd->error = -ESHUTDOWN;
                mmc_request_done(mmc, req);
                return;
        } else {
                struct mmc_data *data = req->data;
                if (!vub300->card_powered) {
                        cmd->error = -ENOMEDIUM;
                        mmc_request_done(mmc, req);
                        return;
                }
                if (!vub300->card_present) {
                        cmd->error = -ENOMEDIUM;
                        mmc_request_done(mmc, req);
                        return;
                }
                if (vub300->usb_transport_fail) {
                        cmd->error = vub300->usb_transport_fail;
                        mmc_request_done(mmc, req);
                        return;
                }
                if (!vub300->interface) {
                        cmd->error = -ENODEV;
                        mmc_request_done(mmc, req);
                        return;
                }
                kref_get(&vub300->kref);
                mutex_lock(&vub300->cmd_mutex);
                mod_timer(&vub300->inactivity_timer, jiffies + HZ);
                /*
                 * for performance we have to return immediately
                 * if the requested data has been offloaded
                 */
                if (cmd->opcode == 52 &&
                    satisfy_request_from_offloaded_data(vub300, cmd)) {
                        cmd->error = 0;
                        mutex_unlock(&vub300->cmd_mutex);
                        kref_put(&vub300->kref, vub300_delete);
                        mmc_request_done(mmc, req);
                        return;
                } else {
                        vub300->cmd = cmd;
                        vub300->req = req;
                        vub300->data = data;
                        if (data)
                                vub300->datasize = data->blksz * data->blocks;
                        else
                                vub300->datasize = 0;
                        vub300_queue_cmnd_work(vub300);
                        mutex_unlock(&vub300->cmd_mutex);
                        kref_put(&vub300->kref, vub300_delete);
                        /*
                         * the kernel lock diagnostics complain
                         * if the cmd_mutex * is "passed on"
                         * to the cmndwork thread,
                         * so we must release it now
                         * and re-acquire it in the cmndwork thread
                         */
                }
        }
}

static void __set_clock_speed(struct vub300_mmc_host *vub300, u8 buf[8],
                              struct mmc_ios *ios)
{
        int buf_array_size = 8; /* ARRAY_SIZE(buf) does not work !!! */
        int retval;
        u32 kHzClock;
        if (ios->clock >= 48000000)
                kHzClock = 48000;
        else if (ios->clock >= 24000000)
                kHzClock = 24000;
        else if (ios->clock >= 20000000)
                kHzClock = 20000;
        else if (ios->clock >= 15000000)
                kHzClock = 15000;
        else if (ios->clock >= 200000)
                kHzClock = 200;
        else
                kHzClock = 0;
        {
                int i;
                u64 c = kHzClock;
                for (i = 0; i < buf_array_size; i++) {
                        buf[i] = c;
                        c >>= 8;
                }
        }
        retval =
                usb_control_msg(vub300->udev, usb_sndctrlpipe(vub300->udev, 0),
                                SET_CLOCK_SPEED,
                                USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,

                                0x00, 0x00, buf, buf_array_size, HZ);
        if (retval != 8) {
                dev_err(&vub300->udev->dev, "SET_CLOCK_SPEED"
                        " %dkHz failed with retval=%d\n", kHzClock, retval);
        } else {
                dev_dbg(&vub300->udev->dev, "SET_CLOCK_SPEED"
                        " %dkHz\n", kHzClock);
        }
}

static void vub300_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
{                               /* NOT irq */
        struct vub300_mmc_host *vub300 = mmc_priv(mmc);
        if (!vub300->interface)
                return;
        kref_get(&vub300->kref);
        mutex_lock(&vub300->cmd_mutex);
        if ((ios->power_mode == MMC_POWER_OFF) && vub300->card_powered) {
                vub300->card_powered = 0;
                usb_control_msg(vub300->udev, usb_sndctrlpipe(vub300->udev, 0),
                                SET_SD_POWER,
                                USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
                                0x0000, 0x0000, NULL, 0, HZ);
                /* must wait for the VUB300 u-proc to boot up */
                msleep(600);
        } else if ((ios->power_mode == MMC_POWER_UP) && !vub300->card_powered) {
                usb_control_msg(vub300->udev, usb_sndctrlpipe(vub300->udev, 0),
                                SET_SD_POWER,
                                USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
                                0x0001, 0x0000, NULL, 0, HZ);
                msleep(600);
                vub300->card_powered = 1;
        } else if (ios->power_mode == MMC_POWER_ON) {
                u8 *buf = kmalloc(8, GFP_KERNEL);
                if (buf) {
                        __set_clock_speed(vub300, buf, ios);
                        kfree(buf);
                }
        } else {
                /* this should mean no change of state */
        }
        mutex_unlock(&vub300->cmd_mutex);
        kref_put(&vub300->kref, vub300_delete);
}

static int vub300_mmc_get_ro(struct mmc_host *mmc)
{
        struct vub300_mmc_host *vub300 = mmc_priv(mmc);
        return vub300->read_only;
}

static void vub300_enable_sdio_irq(struct mmc_host *mmc, int enable)
{                               /* NOT irq */
        struct vub300_mmc_host *vub300 = mmc_priv(mmc);
        if (!vub300->interface)
                return;
        kref_get(&vub300->kref);
        if (enable) {
                mutex_lock(&vub300->irq_mutex);
                if (vub300->irqs_queued) {
                        vub300->irqs_queued -= 1;
                        mmc_signal_sdio_irq(vub300->mmc);
                } else if (vub300->irq_disabled) {
                        vub300->irq_disabled = 0;
                        vub300->irq_enabled = 1;
                        vub300_queue_poll_work(vub300, 0);
                } else if (vub300->irq_enabled) {
                        /* this should not happen, so we will just ignore it */
                } else {
                        vub300->irq_enabled = 1;
                        vub300_queue_poll_work(vub300, 0);
                }
                mutex_unlock(&vub300->irq_mutex);
        } else {
                vub300->irq_enabled = 0;
        }
        kref_put(&vub300->kref, vub300_delete);
}

static void vub300_init_card(struct mmc_host *mmc, struct mmc_card *card)
{                               /* NOT irq */
        struct vub300_mmc_host *vub300 = mmc_priv(mmc);
        dev_info(&vub300->udev->dev, "NO host QUIRKS for this card\n");
}

static struct mmc_host_ops vub300_mmc_ops = {
        .request = vub300_mmc_request,
        .set_ios = vub300_mmc_set_ios,
        .get_ro = vub300_mmc_get_ro,
        .enable_sdio_irq = vub300_enable_sdio_irq,
        .init_card = vub300_init_card,
};

static int vub300_probe(struct usb_interface *interface,
                        const struct usb_device_id *id)
{                               /* NOT irq */
        struct vub300_mmc_host *vub300;
        struct usb_host_interface *iface_desc;
        struct usb_device *udev = usb_get_dev(interface_to_usbdev(interface));
        int i;
        int retval = -ENOMEM;
        struct urb *command_out_urb;
        struct urb *command_res_urb;
        struct mmc_host *mmc;
        char manufacturer[48];
        char product[32];
        char serial_number[32];
        usb_string(udev, udev->descriptor.iManufacturer, manufacturer,
                   sizeof(manufacturer));
        usb_string(udev, udev->descriptor.iProduct, product, sizeof(product));
        usb_string(udev, udev->descriptor.iSerialNumber, serial_number,
                   sizeof(serial_number));
        dev_info(&udev->dev, "probing VID:PID(%04X:%04X) %s %s %s\n",
                 udev->descriptor.idVendor, udev->descriptor.idProduct,
                 manufacturer, product, serial_number);
        command_out_urb = usb_alloc_urb(0, GFP_KERNEL);
        if (!command_out_urb) {
                retval = -ENOMEM;
                goto error0;
        }
        command_res_urb = usb_alloc_urb(0, GFP_KERNEL);
        if (!command_res_urb) {
                retval = -ENOMEM;
                goto error1;
        }
        /* this also allocates memory for our VUB300 mmc host device */
        mmc = mmc_alloc_host(sizeof(struct vub300_mmc_host), &udev->dev);
        if (!mmc) {
                retval = -ENOMEM;
                dev_err(&udev->dev, "not enough memory for the mmc_host\n");
                goto error4;
        }
        /* MMC core transfer sizes tunable parameters */
        mmc->caps = 0;
        if (!force_1_bit_data_xfers)
                mmc->caps |= MMC_CAP_4_BIT_DATA;
        if (!force_polling_for_irqs)
                mmc->caps |= MMC_CAP_SDIO_IRQ;
        mmc->caps &= ~MMC_CAP_NEEDS_POLL;
        /*
         * MMC_CAP_NEEDS_POLL causes core.c:mmc_rescan() to poll
         * for devices which results in spurious CMD7's being
         * issued which stops some SDIO cards from working
         */
        if (limit_speed_to_24_MHz) {
                mmc->caps |= MMC_CAP_MMC_HIGHSPEED;
                mmc->caps |= MMC_CAP_SD_HIGHSPEED;
                mmc->f_max = 24000000;
                dev_info(&udev->dev, "limiting SDIO speed to 24_MHz\n");
        } else {
                mmc->caps |= MMC_CAP_MMC_HIGHSPEED;
                mmc->caps |= MMC_CAP_SD_HIGHSPEED;
                mmc->f_max = 48000000;
        }
        mmc->f_min = 200000;
        mmc->max_blk_count = 511;
        mmc->max_blk_size = 512;
        mmc->max_segs = 128;
        if (force_max_req_size)
                mmc->max_req_size = force_max_req_size * 1024;
        else
                mmc->max_req_size = 64 * 1024;
        mmc->max_seg_size = mmc->max_req_size;
        mmc->ocr_avail = 0;
        mmc->ocr_avail |= MMC_VDD_165_195;
        mmc->ocr_avail |= MMC_VDD_20_21;
        mmc->ocr_avail |= MMC_VDD_21_22;
        mmc->ocr_avail |= MMC_VDD_22_23;
        mmc->ocr_avail |= MMC_VDD_23_24;
        mmc->ocr_avail |= MMC_VDD_24_25;
        mmc->ocr_avail |= MMC_VDD_25_26;
        mmc->ocr_avail |= MMC_VDD_26_27;
        mmc->ocr_avail |= MMC_VDD_27_28;
        mmc->ocr_avail |= MMC_VDD_28_29;
        mmc->ocr_avail |= MMC_VDD_29_30;
        mmc->ocr_avail |= MMC_VDD_30_31;
        mmc->ocr_avail |= MMC_VDD_31_32;
        mmc->ocr_avail |= MMC_VDD_32_33;
        mmc->ocr_avail |= MMC_VDD_33_34;
        mmc->ocr_avail |= MMC_VDD_34_35;
        mmc->ocr_avail |= MMC_VDD_35_36;
        mmc->ops = &vub300_mmc_ops;
        vub300 = mmc_priv(mmc);
        vub300->mmc = mmc;
        vub300->card_powered = 0;
        vub300->bus_width = 0;
        vub300->cmnd.head.block_size[0] = 0x00;
        vub300->cmnd.head.block_size[1] = 0x00;
        vub300->app_spec = 0;
        mutex_init(&vub300->cmd_mutex);
        mutex_init(&vub300->irq_mutex);
        vub300->command_out_urb = command_out_urb;
        vub300->command_res_urb = command_res_urb;
        vub300->usb_timed_out = 0;
        vub300->dynamic_register_count = 0;

        for (i = 0; i < ARRAY_SIZE(vub300->fn); i++) {
                vub300->fn[i].offload_point = 0;
                vub300->fn[i].offload_count = 0;
        }

        vub300->total_offload_count = 0;
        vub300->irq_enabled = 0;
        vub300->irq_disabled = 0;
        vub300->irqs_queued = 0;

        for (i = 0; i < ARRAY_SIZE(vub300->sdio_register); i++)
                vub300->sdio_register[i++].activate = 0;

        vub300->udev = udev;
        vub300->interface = interface;
        vub300->cmnd_res_ep = 0;
        vub300->cmnd_out_ep = 0;
        vub300->data_inp_ep = 0;
        vub300->data_out_ep = 0;

        for (i = 0; i < ARRAY_SIZE(vub300->fbs); i++)
                vub300->fbs[i] = 512;

        /*
         *      set up the endpoint information
         *
         * use the first pair of bulk-in and bulk-out
         *     endpoints for Command/Response+Interrupt
         *
         * use the second pair of bulk-in and bulk-out
         *     endpoints for Data In/Out
         */
        vub300->large_usb_packets = 0;
        iface_desc = interface->cur_altsetting;
        for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
                struct usb_endpoint_descriptor *endpoint =
                        &iface_desc->endpoint[i].desc;
                dev_info(&vub300->udev->dev,
                         "vub300 testing %s EndPoint(%d) %02X\n",
                         usb_endpoint_is_bulk_in(endpoint) ? "BULK IN" :
                         usb_endpoint_is_bulk_out(endpoint) ? "BULK OUT" :
                         "UNKNOWN", i, endpoint->bEndpointAddress);
                if (endpoint->wMaxPacketSize > 64)
                        vub300->large_usb_packets = 1;
                if (usb_endpoint_is_bulk_in(endpoint)) {
                        if (!vub300->cmnd_res_ep) {
                                vub300->cmnd_res_ep =
                                        endpoint->bEndpointAddress;
                        } else if (!vub300->data_inp_ep) {
                                vub300->data_inp_ep =
                                        endpoint->bEndpointAddress;
                        } else {
                                dev_warn(&vub300->udev->dev,
                                         "ignoring"
                                         " unexpected bulk_in endpoint");
                        }
                } else if (usb_endpoint_is_bulk_out(endpoint)) {
                        if (!vub300->cmnd_out_ep) {
                                vub300->cmnd_out_ep =
                                        endpoint->bEndpointAddress;
                        } else if (!vub300->data_out_ep) {
                                vub300->data_out_ep =
                                        endpoint->bEndpointAddress;
                        } else {
                                dev_warn(&vub300->udev->dev,
                                         "ignoring"
                                         " unexpected bulk_out endpoint");
                        }
                } else {
                        dev_warn(&vub300->udev->dev,
                                 "vub300 ignoring EndPoint(%d) %02X", i,
                                 endpoint->bEndpointAddress);
                }
        }
        if (vub300->cmnd_res_ep && vub300->cmnd_out_ep &&
            vub300->data_inp_ep && vub300->data_out_ep) {
                dev_info(&vub300->udev->dev,
                         "vub300 %s packets"
                         " using EndPoints %02X %02X %02X %02X\n",
                         vub300->large_usb_packets ? "LARGE" : "SMALL",
                         vub300->cmnd_out_ep, vub300->cmnd_res_ep,
                         vub300->data_out_ep, vub300->data_inp_ep);
                /* we have the expected EndPoints */
        } else {
                dev_err(&vub300->udev->dev,
                    "Could not find two sets of bulk-in/out endpoint pairs\n");
                retval = -EINVAL;
                goto error5;
        }
        retval =
                usb_control_msg(vub300->udev, usb_rcvctrlpipe(vub300->udev, 0),
                                GET_HC_INF0,
                                USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
                                0x0000, 0x0000, &vub300->hc_info,
                                sizeof(vub300->hc_info), HZ);
        if (retval < 0)
                goto error5;
        retval =
                usb_control_msg(vub300->udev, usb_rcvctrlpipe(vub300->udev, 0),
                                SET_ROM_WAIT_STATES,
                                USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
                                firmware_rom_wait_states, 0x0000, NULL, 0, HZ);
        if (retval < 0)
                goto error5;
        dev_info(&vub300->udev->dev,
                 "operating_mode = %s %s %d MHz %s %d byte USB packets\n",
                 (mmc->caps & MMC_CAP_SDIO_IRQ) ? "IRQs" : "POLL",
                 (mmc->caps & MMC_CAP_4_BIT_DATA) ? "4-bit" : "1-bit",
                 mmc->f_max / 1000000,
                 pad_input_to_usb_pkt ? "padding input data to" : "with",
                 vub300->large_usb_packets ? 512 : 64);
        retval =
                usb_control_msg(vub300->udev, usb_rcvctrlpipe(vub300->udev, 0),
                                GET_SYSTEM_PORT_STATUS,
                                USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
                                0x0000, 0x0000, &vub300->system_port_status,
                                sizeof(vub300->system_port_status), HZ);
        if (retval < 0) {
                goto error4;
        } else if (sizeof(vub300->system_port_status) == retval) {
                vub300->card_present =
                        (0x0001 & vub300->system_port_status.port_flags) ? 1 : 0;
                vub300->read_only =
                        (0x0010 & vub300->system_port_status.port_flags) ? 1 : 0;
        } else {
                goto error4;
        }
        usb_set_intfdata(interface, vub300);
        INIT_DELAYED_WORK(&vub300->pollwork, vub300_pollwork_thread);
        INIT_WORK(&vub300->cmndwork, vub300_cmndwork_thread);
        INIT_WORK(&vub300->deadwork, vub300_deadwork_thread);
        kref_init(&vub300->kref);
        init_timer(&vub300->sg_transfer_timer);
        vub300->sg_transfer_timer.data = (unsigned long)vub300;
        vub300->sg_transfer_timer.function = vub300_sg_timed_out;
        kref_get(&vub300->kref);
        init_timer(&vub300->inactivity_timer);
        vub300->inactivity_timer.data = (unsigned long)vub300;
        vub300->inactivity_timer.function = vub300_inactivity_timer_expired;
        vub300->inactivity_timer.expires = jiffies + HZ;
        add_timer(&vub300->inactivity_timer);
        if (vub300->card_present)
                dev_info(&vub300->udev->dev,
                         "USB vub300 remote SDIO host controller[%d]"
                         "connected with SD/SDIO card inserted\n",
                         interface_to_InterfaceNumber(interface));
        else
                dev_info(&vub300->udev->dev,
                         "USB vub300 remote SDIO host controller[%d]"
                         "connected with no SD/SDIO card inserted\n",
                         interface_to_InterfaceNumber(interface));
        mmc_add_host(mmc);
        return 0;
error5:
        mmc_free_host(mmc);
        /*
         * and hence also frees vub300
         * which is contained at the end of struct mmc
         */
error4:
        usb_free_urb(command_res_urb);
error1:
        usb_free_urb(command_out_urb);
error0:
        usb_put_dev(udev);
        return retval;
}

static void vub300_disconnect(struct usb_interface *interface)
{                               /* NOT irq */
        struct vub300_mmc_host *vub300 = usb_get_intfdata(interface);
        if (!vub300 || !vub300->mmc) {
                return;
        } else {
                struct mmc_host *mmc = vub300->mmc;
                if (!vub300->mmc) {
                        return;
                } else {
                        int ifnum = interface_to_InterfaceNumber(interface);
                        usb_set_intfdata(interface, NULL);
                        /* prevent more I/O from starting */
                        vub300->interface = NULL;
                        kref_put(&vub300->kref, vub300_delete);
                        mmc_remove_host(mmc);
                        pr_info("USB vub300 remote SDIO host controller[%d]"
                                " now disconnected", ifnum);
                        return;
                }
        }
}

#ifdef CONFIG_PM
static int vub300_suspend(struct usb_interface *intf, pm_message_t message)
{
        return 0;
}

static int vub300_resume(struct usb_interface *intf)
{
        return 0;
}
#else
#define vub300_suspend NULL
#define vub300_resume NULL
#endif
static int vub300_pre_reset(struct usb_interface *intf)
{                               /* NOT irq */
        struct vub300_mmc_host *vub300 = usb_get_intfdata(intf);
        mutex_lock(&vub300->cmd_mutex);
        return 0;
}

static int vub300_post_reset(struct usb_interface *intf)
{                               /* NOT irq */
        struct vub300_mmc_host *vub300 = usb_get_intfdata(intf);
        /* we are sure no URBs are active - no locking needed */
        vub300->errors = -EPIPE;
        mutex_unlock(&vub300->cmd_mutex);
        return 0;
}

static struct usb_driver vub300_driver = {
        .name = "vub300",
        .probe = vub300_probe,
        .disconnect = vub300_disconnect,
        .suspend = vub300_suspend,
        .resume = vub300_resume,
        .pre_reset = vub300_pre_reset,
        .post_reset = vub300_post_reset,
        .id_table = vub300_table,
        .supports_autosuspend = 1,
};

static int __init vub300_init(void)
{                               /* NOT irq */
        int result;

        pr_info("VUB300 Driver rom wait states = %02X irqpoll timeout = %04X",
                firmware_rom_wait_states, 0x0FFFF & firmware_irqpoll_timeout);
        cmndworkqueue = create_singlethread_workqueue("kvub300c");
        if (!cmndworkqueue) {
                pr_err("not enough memory for the REQUEST workqueue");
                result = -ENOMEM;
                goto out1;
        }
        pollworkqueue = create_singlethread_workqueue("kvub300p");
        if (!pollworkqueue) {
                pr_err("not enough memory for the IRQPOLL workqueue");
                result = -ENOMEM;
                goto out2;
        }
        deadworkqueue = create_singlethread_workqueue("kvub300d");
        if (!deadworkqueue) {
                pr_err("not enough memory for the EXPIRED workqueue");
                result = -ENOMEM;
                goto out3;
        }
        result = usb_register(&vub300_driver);
        if (result) {
                pr_err("usb_register failed. Error number %d", result);
                goto out4;
        }
        return 0;
out4:
        destroy_workqueue(deadworkqueue);
out3:
        destroy_workqueue(pollworkqueue);
out2:
        destroy_workqueue(cmndworkqueue);
out1:
        return result;
}

static void __exit vub300_exit(void)
{
        usb_deregister(&vub300_driver);
        flush_workqueue(cmndworkqueue);
        flush_workqueue(pollworkqueue);
        flush_workqueue(deadworkqueue);
        destroy_workqueue(cmndworkqueue);
        destroy_workqueue(pollworkqueue);
        destroy_workqueue(deadworkqueue);
}

module_init(vub300_init);
module_exit(vub300_exit);

MODULE_AUTHOR("Tony Olech <tony.olech@elandigitalsystems.com>");
MODULE_DESCRIPTION("VUB300 USB to SD/MMC/SDIO adapter driver");
MODULE_LICENSE("GPL");