/*
        Copyright (C) 2004 - 2009 Ivo van Doorn <IvDoorn@gmail.com>
        <http://rt2x00.serialmonkey.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; either version 2 of the License, or
        (at your option) any later version.

        This program is distributed in the hope that it will be useful,
        but WITHOUT ANY WARRANTY; without even the implied warranty of
        MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
        GNU General Public License for more details.

        You should have received a copy of the GNU General Public License
        along with this program; if not, see <http://www.gnu.org/licenses/>.
 */

/*
        Module: rt2x00usb
        Abstract: Data structures for the rt2x00usb module.
 */

#ifndef RT2X00USB_H
#define RT2X00USB_H

#include <linux/usb.h>

#define to_usb_device_intf(d) \
({ \
        struct usb_interface *intf = to_usb_interface(d); \
        interface_to_usbdev(intf); \
})

/*
 * For USB vendor requests we need to pass a timeout time in ms, for this we
 * use the REGISTER_TIMEOUT, however when loading firmware or read EEPROM
 * a higher value is required. In that case we use the REGISTER_TIMEOUT_FIRMWARE
 * and EEPROM_TIMEOUT.
 */
#define REGISTER_TIMEOUT                100
#define REGISTER_TIMEOUT_FIRMWARE       1000
#define EEPROM_TIMEOUT                  2000

/*
 * Cache size
 */
#define CSR_CACHE_SIZE                  64

/*
 * USB request types.
 */
#define USB_VENDOR_REQUEST      ( USB_TYPE_VENDOR | USB_RECIP_DEVICE )
#define USB_VENDOR_REQUEST_IN   ( USB_DIR_IN | USB_VENDOR_REQUEST )
#define USB_VENDOR_REQUEST_OUT  ( USB_DIR_OUT | USB_VENDOR_REQUEST )

/**
 * enum rt2x00usb_vendor_request: USB vendor commands.
 */
enum rt2x00usb_vendor_request {
        USB_DEVICE_MODE = 1,
        USB_SINGLE_WRITE = 2,
        USB_SINGLE_READ = 3,
        USB_MULTI_WRITE = 6,
        USB_MULTI_READ = 7,
        USB_EEPROM_WRITE = 8,
        USB_EEPROM_READ = 9,
        USB_LED_CONTROL = 10, /* RT73USB */
        USB_RX_CONTROL = 12,
};

/**
 * enum rt2x00usb_mode_offset: Device modes offset.
 */
enum rt2x00usb_mode_offset {
        USB_MODE_RESET = 1,
        USB_MODE_UNPLUG = 2,
        USB_MODE_FUNCTION = 3,
        USB_MODE_TEST = 4,
        USB_MODE_SLEEP = 7,     /* RT73USB */
        USB_MODE_FIRMWARE = 8,  /* RT73USB */
        USB_MODE_WAKEUP = 9,    /* RT73USB */
        USB_MODE_AUTORUN = 17, /* RT2800USB */
};

/**
 * rt2x00usb_vendor_request - Send register command to device
 * @rt2x00dev: Pointer to &struct rt2x00_dev
 * @request: USB vendor command (See &enum rt2x00usb_vendor_request)
 * @requesttype: Request type &USB_VENDOR_REQUEST_*
 * @offset: Register offset to perform action on
 * @value: Value to write to device
 * @buffer: Buffer where information will be read/written to by device
 * @buffer_length: Size of &buffer
 * @timeout: Operation timeout
 *
 * This is the main function to communicate with the device,
 * the &buffer argument _must_ either be NULL or point to
 * a buffer allocated by kmalloc. Failure to do so can lead
 * to unexpected behavior depending on the architecture.
 */
int rt2x00usb_vendor_request(struct rt2x00_dev *rt2x00dev,
                             const u8 request, const u8 requesttype,
                             const u16 offset, const u16 value,
                             void *buffer, const u16 buffer_length,
                             const int timeout);

/**
 * rt2x00usb_vendor_request_buff - Send register command to device (buffered)
 * @rt2x00dev: Pointer to &struct rt2x00_dev
 * @request: USB vendor command (See &enum rt2x00usb_vendor_request)
 * @requesttype: Request type &USB_VENDOR_REQUEST_*
 * @offset: Register offset to perform action on
 * @buffer: Buffer where information will be read/written to by device
 * @buffer_length: Size of &buffer
 *
 * This function will use a previously with kmalloc allocated cache
 * to communicate with the device. The contents of the buffer pointer
 * will be copied to this cache when writing, or read from the cache
 * when reading.
 * Buffers send to &rt2x00usb_vendor_request _must_ be allocated with
 * kmalloc. Hence the reason for using a previously allocated cache
 * which has been allocated properly.
 */
int rt2x00usb_vendor_request_buff(struct rt2x00_dev *rt2x00dev,
                                  const u8 request, const u8 requesttype,
                                  const u16 offset, void *buffer,
                                  const u16 buffer_length);

/**
 * rt2x00usb_vendor_request_buff - Send register command to device (buffered)
 * @rt2x00dev: Pointer to &struct rt2x00_dev
 * @request: USB vendor command (See &enum rt2x00usb_vendor_request)
 * @requesttype: Request type &USB_VENDOR_REQUEST_*
 * @offset: Register offset to perform action on
 * @buffer: Buffer where information will be read/written to by device
 * @buffer_length: Size of &buffer
 * @timeout: Operation timeout
 *
 * A version of &rt2x00usb_vendor_request_buff which must be called
 * if the usb_cache_mutex is already held.
 */
int rt2x00usb_vendor_req_buff_lock(struct rt2x00_dev *rt2x00dev,
                                   const u8 request, const u8 requesttype,
                                   const u16 offset, void *buffer,
                                   const u16 buffer_length, const int timeout);

/**
 * rt2x00usb_vendor_request_sw - Send single register command to device
 * @rt2x00dev: Pointer to &struct rt2x00_dev
 * @request: USB vendor command (See &enum rt2x00usb_vendor_request)
 * @offset: Register offset to perform action on
 * @value: Value to write to device
 * @timeout: Operation timeout
 *
 * Simple wrapper around rt2x00usb_vendor_request to write a single
 * command to the device. Since we don't use the buffer argument we
 * don't have to worry about kmalloc here.
 */
static inline int rt2x00usb_vendor_request_sw(struct rt2x00_dev *rt2x00dev,
                                              const u8 request,
                                              const u16 offset,
                                              const u16 value,
                                              const int timeout)
{
        return rt2x00usb_vendor_request(rt2x00dev, request,
                                        USB_VENDOR_REQUEST_OUT, offset,
                                        value, NULL, 0, timeout);
}

/**
 * rt2x00usb_eeprom_read - Read eeprom from device
 * @rt2x00dev: Pointer to &struct rt2x00_dev
 * @eeprom: Pointer to eeprom array to store the information in
 * @length: Number of bytes to read from the eeprom
 *
 * Simple wrapper around rt2x00usb_vendor_request to read the eeprom
 * from the device. Note that the eeprom argument _must_ be allocated using
 * kmalloc for correct handling inside the kernel USB layer.
 */
static inline int rt2x00usb_eeprom_read(struct rt2x00_dev *rt2x00dev,
                                        __le16 *eeprom, const u16 length)
{
        return rt2x00usb_vendor_request(rt2x00dev, USB_EEPROM_READ,
                                        USB_VENDOR_REQUEST_IN, 0, 0,
                                        eeprom, length, EEPROM_TIMEOUT);
}

/**
 * rt2x00usb_register_read - Read 32bit register word
 * @rt2x00dev: Device pointer, see &struct rt2x00_dev.
 * @offset: Register offset
 *
 * This function is a simple wrapper for 32bit register access
 * through rt2x00usb_vendor_request_buff().
 */
static inline u32 rt2x00usb_register_read(struct rt2x00_dev *rt2x00dev,
                                          const unsigned int offset)
{
        __le32 reg = 0;
        rt2x00usb_vendor_request_buff(rt2x00dev, USB_MULTI_READ,
                                      USB_VENDOR_REQUEST_IN, offset,
                                      &reg, sizeof(reg));
        return le32_to_cpu(reg);
}

/**
 * rt2x00usb_register_read_lock - Read 32bit register word
 * @rt2x00dev: Device pointer, see &struct rt2x00_dev.
 * @offset: Register offset
 *
 * This function is a simple wrapper for 32bit register access
 * through rt2x00usb_vendor_req_buff_lock().
 */
static inline u32 rt2x00usb_register_read_lock(struct rt2x00_dev *rt2x00dev,
                                               const unsigned int offset)
{
        __le32 reg = 0;
        rt2x00usb_vendor_req_buff_lock(rt2x00dev, USB_MULTI_READ,
                                       USB_VENDOR_REQUEST_IN, offset,
                                       &reg, sizeof(reg), REGISTER_TIMEOUT);
        return le32_to_cpu(reg);
}

/**
 * rt2x00usb_register_multiread - Read 32bit register words
 * @rt2x00dev: Device pointer, see &struct rt2x00_dev.
 * @offset: Register offset
 * @value: Pointer to where register contents should be stored
 * @length: Length of the data
 *
 * This function is a simple wrapper for 32bit register access
 * through rt2x00usb_vendor_request_buff().
 */
static inline void rt2x00usb_register_multiread(struct rt2x00_dev *rt2x00dev,
                                                const unsigned int offset,
                                                void *value, const u32 length)
{
        rt2x00usb_vendor_request_buff(rt2x00dev, USB_MULTI_READ,
                                      USB_VENDOR_REQUEST_IN, offset,
                                      value, length);
}

/**
 * rt2x00usb_register_write - Write 32bit register word
 * @rt2x00dev: Device pointer, see &struct rt2x00_dev.
 * @offset: Register offset
 * @value: Data which should be written
 *
 * This function is a simple wrapper for 32bit register access
 * through rt2x00usb_vendor_request_buff().
 */
static inline void rt2x00usb_register_write(struct rt2x00_dev *rt2x00dev,
                                            const unsigned int offset,
                                            u32 value)
{
        __le32 reg = cpu_to_le32(value);
        rt2x00usb_vendor_request_buff(rt2x00dev, USB_MULTI_WRITE,
                                      USB_VENDOR_REQUEST_OUT, offset,
                                      &reg, sizeof(reg));
}

/**
 * rt2x00usb_register_write_lock - Write 32bit register word
 * @rt2x00dev: Device pointer, see &struct rt2x00_dev.
 * @offset: Register offset
 * @value: Data which should be written
 *
 * This function is a simple wrapper for 32bit register access
 * through rt2x00usb_vendor_req_buff_lock().
 */
static inline void rt2x00usb_register_write_lock(struct rt2x00_dev *rt2x00dev,
                                                 const unsigned int offset,
                                                 u32 value)
{
        __le32 reg = cpu_to_le32(value);
        rt2x00usb_vendor_req_buff_lock(rt2x00dev, USB_MULTI_WRITE,
                                       USB_VENDOR_REQUEST_OUT, offset,
                                       &reg, sizeof(reg), REGISTER_TIMEOUT);
}

/**
 * rt2x00usb_register_multiwrite - Write 32bit register words
 * @rt2x00dev: Device pointer, see &struct rt2x00_dev.
 * @offset: Register offset
 * @value: Data which should be written
 * @length: Length of the data
 *
 * This function is a simple wrapper for 32bit register access
 * through rt2x00usb_vendor_request_buff().
 */
static inline void rt2x00usb_register_multiwrite(struct rt2x00_dev *rt2x00dev,
                                                 const unsigned int offset,
                                                 const void *value,
                                                 const u32 length)
{
        rt2x00usb_vendor_request_buff(rt2x00dev, USB_MULTI_WRITE,
                                      USB_VENDOR_REQUEST_OUT, offset,
                                      (void *)value, length);
}

/**
 * rt2x00usb_regbusy_read - Read from register with busy check
 * @rt2x00dev: Device pointer, see &struct rt2x00_dev.
 * @offset: Register offset
 * @field: Field to check if register is busy
 * @reg: Pointer to where register contents should be stored
 *
 * This function will read the given register, and checks if the
 * register is busy. If it is, it will sleep for a couple of
 * microseconds before reading the register again. If the register
 * is not read after a certain timeout, this function will return
 * FALSE.
 */
int rt2x00usb_regbusy_read(struct rt2x00_dev *rt2x00dev,
                           const unsigned int offset,
                           const struct rt2x00_field32 field,
                           u32 *reg);

/**
 * rt2x00usb_register_read_async - Asynchronously read 32bit register word
 * @rt2x00dev: Device pointer, see &struct rt2x00_dev.
 * @offset: Register offset
 * @callback: Functon to call when read completes.
 *
 * Submit a control URB to read a 32bit register. This safe to
 * be called from atomic context.  The callback will be called
 * when the URB completes. Otherwise the function is similar
 * to rt2x00usb_register_read().
 * When the callback function returns false, the memory will be cleaned up,
 * when it returns true, the urb will be fired again.
 */
void rt2x00usb_register_read_async(struct rt2x00_dev *rt2x00dev,
                                   const unsigned int offset,
                                   bool (*callback)(struct rt2x00_dev*, int, u32));

/*
 * Radio handlers
 */
void rt2x00usb_disable_radio(struct rt2x00_dev *rt2x00dev);

/**
 * struct queue_entry_priv_usb: Per entry USB specific information
 *
 * @urb: Urb structure used for device communication.
 */
struct queue_entry_priv_usb {
        struct urb *urb;
};

/**
 * struct queue_entry_priv_usb_bcn: Per TX entry USB specific information
 *
 * The first section should match &struct queue_entry_priv_usb exactly.
 * rt2500usb can use this structure to send a guardian byte when working
 * with beacons.
 *
 * @urb: Urb structure used for device communication.
 * @guardian_data: Set to 0, used for sending the guardian data.
 * @guardian_urb: Urb structure used to send the guardian data.
 */
struct queue_entry_priv_usb_bcn {
        struct urb *urb;

        unsigned int guardian_data;
        struct urb *guardian_urb;
};

/**
 * rt2x00usb_kick_queue - Kick data queue
 * @queue: Data queue to kick
 *
 * This will walk through all entries of the queue and push all pending
 * frames to the hardware as a single burst.
 */
void rt2x00usb_kick_queue(struct data_queue *queue);

/**
 * rt2x00usb_flush_queue - Flush data queue
 * @queue: Data queue to stop
 * @drop: True to drop all pending frames.
 *
 * This will walk through all entries of the queue and will optionally
 * kill all URB's which were send to the device, or at least wait until
 * they have been returned from the device..
 */
void rt2x00usb_flush_queue(struct data_queue *queue, bool drop);

/**
 * rt2x00usb_watchdog - Watchdog for USB communication
 * @rt2x00dev: Pointer to &struct rt2x00_dev
 *
 * Check the health of the USB communication and determine
 * if timeouts have occurred. If this is the case, this function
 * will reset all communication to restore functionality again.
 */
void rt2x00usb_watchdog(struct rt2x00_dev *rt2x00dev);

/*
 * Device initialization handlers.
 */
void rt2x00usb_clear_entry(struct queue_entry *entry);
int rt2x00usb_initialize(struct rt2x00_dev *rt2x00dev);
void rt2x00usb_uninitialize(struct rt2x00_dev *rt2x00dev);

/*
 * USB driver handlers.
 */
int rt2x00usb_probe(struct usb_interface *usb_intf,
                    const struct rt2x00_ops *ops);
void rt2x00usb_disconnect(struct usb_interface *usb_intf);
#ifdef CONFIG_PM
int rt2x00usb_suspend(struct usb_interface *usb_intf, pm_message_t state);
int rt2x00usb_resume(struct usb_interface *usb_intf);
#else
#define rt2x00usb_suspend       NULL
#define rt2x00usb_resume        NULL
#endif /* CONFIG_PM */

#endif /* RT2X00USB_H */