/*
 *  tm6000-input.c - driver for TM5600/TM6000/TM6010 USB video capture devices
 *
 *  Copyright (C) 2010 Stefan Ringel <stefan.ringel@arcor.de>
 *
 *  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
 *
 *  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.
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/delay.h>

#include <linux/input.h>
#include <linux/usb.h>

#include <media/rc-core.h>

#include "tm6000.h"
#include "tm6000-regs.h"

static unsigned int ir_debug;
module_param(ir_debug, int, 0644);
MODULE_PARM_DESC(ir_debug, "debug message level");

static unsigned int enable_ir = 1;
module_param(enable_ir, int, 0644);
MODULE_PARM_DESC(enable_ir, "enable ir (default is enable)");

static unsigned int ir_clock_mhz = 12;
module_param(ir_clock_mhz, int, 0644);
MODULE_PARM_DESC(ir_clock_mhz, "ir clock, in MHz");

#define URB_SUBMIT_DELAY        100     /* ms - Delay to submit an URB request on retrial and init */
#define URB_INT_LED_DELAY       100     /* ms - Delay to turn led on again on int mode */

#undef dprintk

#define dprintk(level, fmt, arg...) do {\
        if (ir_debug >= level) \
                printk(KERN_DEBUG "%s/ir: " fmt, ir->name , ## arg); \
        } while (0)

struct tm6000_ir_poll_result {
        u16 rc_data;
};

struct tm6000_IR {
        struct tm6000_core      *dev;
        struct rc_dev           *rc;
        char                    name[32];
        char                    phys[32];

        /* poll expernal decoder */
        int                     polling;
        struct delayed_work     work;
        u8                      wait:1;
        u8                      pwled:2;
        u8                      submit_urb:1;
        struct urb              *int_urb;

        /* IR device properties */
        u64                     rc_proto;
};

void tm6000_ir_wait(struct tm6000_core *dev, u8 state)
{
        struct tm6000_IR *ir = dev->ir;

        if (!dev->ir)
                return;

        dprintk(2, "%s: %i\n",__func__, ir->wait);

        if (state)
                ir->wait = 1;
        else
                ir->wait = 0;
}

static int tm6000_ir_config(struct tm6000_IR *ir)
{
        struct tm6000_core *dev = ir->dev;
        u32 pulse = 0, leader = 0;

        dprintk(2, "%s\n",__func__);

        /*
         * The IR decoder supports RC-5 or NEC, with a configurable timing.
         * The timing configuration there is not that accurate, as it uses
         * approximate values. The NEC spec mentions a 562.5 unit period,
         * and RC-5 uses a 888.8 period.
         * Currently, driver assumes a clock provided by a 12 MHz XTAL, but
         * a modprobe parameter can adjust it.
         * Adjustments are required for other timings.
         * It seems that the 900ms timing for NEC is used to detect a RC-5
         * IR, in order to discard such decoding
         */

        switch (ir->rc_proto) {
        case RC_PROTO_BIT_NEC:
                leader = 900;   /* ms */
                pulse  = 700;   /* ms - the actual value would be 562 */
                break;
        default:
        case RC_PROTO_BIT_RC5:
                leader = 900;   /* ms - from the NEC decoding */
                pulse  = 1780;  /* ms - The actual value would be 1776 */
                break;
        }

        pulse = ir_clock_mhz * pulse;
        leader = ir_clock_mhz * leader;
        if (ir->rc_proto == RC_PROTO_BIT_NEC)
                leader = leader | 0x8000;

        dprintk(2, "%s: %s, %d MHz, leader = 0x%04x, pulse = 0x%06x \n",
                __func__,
                (ir->rc_proto == RC_PROTO_BIT_NEC) ? "NEC" : "RC-5",
                ir_clock_mhz, leader, pulse);

        /* Remote WAKEUP = enable, normal mode, from IR decoder output */
        tm6000_set_reg(dev, TM6010_REQ07_RE5_REMOTE_WAKEUP, 0xfe);

        /* Enable IR reception on non-busrt mode */
        tm6000_set_reg(dev, TM6010_REQ07_RD8_IR, 0x2f);

        /* IR_WKUP_SEL = Low byte in decoded IR data */
        tm6000_set_reg(dev, TM6010_REQ07_RDA_IR_WAKEUP_SEL, 0xff);
        /* IR_WKU_ADD code */
        tm6000_set_reg(dev, TM6010_REQ07_RDB_IR_WAKEUP_ADD, 0xff);

        tm6000_set_reg(dev, TM6010_REQ07_RDC_IR_LEADER1, leader >> 8);
        tm6000_set_reg(dev, TM6010_REQ07_RDD_IR_LEADER0, leader);

        tm6000_set_reg(dev, TM6010_REQ07_RDE_IR_PULSE_CNT1, pulse >> 8);
        tm6000_set_reg(dev, TM6010_REQ07_RDF_IR_PULSE_CNT0, pulse);

        if (!ir->polling)
                tm6000_set_reg(dev, REQ_04_EN_DISABLE_MCU_INT, 2, 0);
        else
                tm6000_set_reg(dev, REQ_04_EN_DISABLE_MCU_INT, 2, 1);
        msleep(10);

        /* Shows that IR is working via the LED */
        tm6000_flash_led(dev, 0);
        msleep(100);
        tm6000_flash_led(dev, 1);
        ir->pwled = 1;

        return 0;
}

static void tm6000_ir_keydown(struct tm6000_IR *ir,
                              const char *buf, unsigned int len)
{
        u8 device, command;
        u32 scancode;
        enum rc_proto protocol;

        if (len < 1)
                return;

        command = buf[0];
        device = (len > 1 ? buf[1] : 0x0);
        switch (ir->rc_proto) {
        case RC_PROTO_BIT_RC5:
                protocol = RC_PROTO_RC5;
                scancode = RC_SCANCODE_RC5(device, command);
                break;
        case RC_PROTO_BIT_NEC:
                protocol = RC_PROTO_NEC;
                scancode = RC_SCANCODE_NEC(device, command);
                break;
        default:
                protocol = RC_PROTO_OTHER;
                scancode = RC_SCANCODE_OTHER(device << 8 | command);
                break;
        }

        dprintk(1, "%s, protocol: 0x%04x, scancode: 0x%08x\n",
                __func__, protocol, scancode);
        rc_keydown(ir->rc, protocol, scancode, 0);
}

static void tm6000_ir_urb_received(struct urb *urb)
{
        struct tm6000_core *dev = urb->context;
        struct tm6000_IR *ir = dev->ir;
        char *buf;

        dprintk(2, "%s\n",__func__);
        if (urb->status < 0 || urb->actual_length <= 0) {
                printk(KERN_INFO "tm6000: IR URB failure: status: %i, length %i\n",
                       urb->status, urb->actual_length);
                ir->submit_urb = 1;
                schedule_delayed_work(&ir->work, msecs_to_jiffies(URB_SUBMIT_DELAY));
                return;
        }
        buf = urb->transfer_buffer;

        if (ir_debug)
                print_hex_dump(KERN_DEBUG, "tm6000: IR data: ",
                               DUMP_PREFIX_OFFSET,16, 1,
                               buf, urb->actual_length, false);

        tm6000_ir_keydown(ir, urb->transfer_buffer, urb->actual_length);

        usb_submit_urb(urb, GFP_ATOMIC);
        /*
         * Flash the led. We can't do it here, as it is running on IRQ context.
         * So, use the scheduler to do it, in a few ms.
         */
        ir->pwled = 2;
        schedule_delayed_work(&ir->work, msecs_to_jiffies(10));
}

static void tm6000_ir_handle_key(struct work_struct *work)
{
        struct tm6000_IR *ir = container_of(work, struct tm6000_IR, work.work);
        struct tm6000_core *dev = ir->dev;
        int rc;
        u8 buf[2];

        if (ir->wait)
                return;

        dprintk(3, "%s\n",__func__);

        rc = tm6000_read_write_usb(dev, USB_DIR_IN |
                USB_TYPE_VENDOR | USB_RECIP_DEVICE,
                REQ_02_GET_IR_CODE, 0, 0, buf, 2);
        if (rc < 0)
                return;

        /* Check if something was read */
        if ((buf[0] & 0xff) == 0xff) {
                if (!ir->pwled) {
                        tm6000_flash_led(dev, 1);
                        ir->pwled = 1;
                }
                return;
        }

        tm6000_ir_keydown(ir, buf, rc);
        tm6000_flash_led(dev, 0);
        ir->pwled = 0;

        /* Re-schedule polling */
        schedule_delayed_work(&ir->work, msecs_to_jiffies(ir->polling));
}

static void tm6000_ir_int_work(struct work_struct *work)
{
        struct tm6000_IR *ir = container_of(work, struct tm6000_IR, work.work);
        struct tm6000_core *dev = ir->dev;
        int rc;

        dprintk(3, "%s, submit_urb = %d, pwled = %d\n",__func__, ir->submit_urb,
                ir->pwled);

        if (ir->submit_urb) {
                dprintk(3, "Resubmit urb\n");
                tm6000_set_reg(dev, REQ_04_EN_DISABLE_MCU_INT, 2, 0);

                rc = usb_submit_urb(ir->int_urb, GFP_ATOMIC);
                if (rc < 0) {
                        printk(KERN_ERR "tm6000: Can't submit an IR interrupt. Error %i\n",
                               rc);
                        /* Retry in 100 ms */
                        schedule_delayed_work(&ir->work, msecs_to_jiffies(URB_SUBMIT_DELAY));
                        return;
                }
                ir->submit_urb = 0;
        }

        /* Led is enabled only if USB submit doesn't fail */
        if (ir->pwled == 2) {
                tm6000_flash_led(dev, 0);
                ir->pwled = 0;
                schedule_delayed_work(&ir->work, msecs_to_jiffies(URB_INT_LED_DELAY));
        } else if (!ir->pwled) {
                tm6000_flash_led(dev, 1);
                ir->pwled = 1;
        }
}

static int tm6000_ir_start(struct rc_dev *rc)
{
        struct tm6000_IR *ir = rc->priv;

        dprintk(2, "%s\n",__func__);

        schedule_delayed_work(&ir->work, 0);

        return 0;
}

static void tm6000_ir_stop(struct rc_dev *rc)
{
        struct tm6000_IR *ir = rc->priv;

        dprintk(2, "%s\n",__func__);

        cancel_delayed_work_sync(&ir->work);
}

static int tm6000_ir_change_protocol(struct rc_dev *rc, u64 *rc_proto)
{
        struct tm6000_IR *ir = rc->priv;

        if (!ir)
                return 0;

        dprintk(2, "%s\n",__func__);

        ir->rc_proto = *rc_proto;

        tm6000_ir_config(ir);
        /* TODO */
        return 0;
}

static int __tm6000_ir_int_start(struct rc_dev *rc)
{
        struct tm6000_IR *ir = rc->priv;
        struct tm6000_core *dev;
        int pipe, size;
        int err = -ENOMEM;

        if (!ir)
                return -ENODEV;
        dev = ir->dev;

        dprintk(2, "%s\n",__func__);

        ir->int_urb = usb_alloc_urb(0, GFP_ATOMIC);
        if (!ir->int_urb)
                return -ENOMEM;

        pipe = usb_rcvintpipe(dev->udev,
                dev->int_in.endp->desc.bEndpointAddress
                & USB_ENDPOINT_NUMBER_MASK);

        size = usb_maxpacket(dev->udev, pipe, usb_pipeout(pipe));
        dprintk(1, "IR max size: %d\n", size);

        ir->int_urb->transfer_buffer = kzalloc(size, GFP_ATOMIC);
        if (ir->int_urb->transfer_buffer == NULL) {
                usb_free_urb(ir->int_urb);
                return err;
        }
        dprintk(1, "int interval: %d\n", dev->int_in.endp->desc.bInterval);

        usb_fill_int_urb(ir->int_urb, dev->udev, pipe,
                ir->int_urb->transfer_buffer, size,
                tm6000_ir_urb_received, dev,
                dev->int_in.endp->desc.bInterval);

        ir->submit_urb = 1;
        schedule_delayed_work(&ir->work, msecs_to_jiffies(URB_SUBMIT_DELAY));

        return 0;
}

static void __tm6000_ir_int_stop(struct rc_dev *rc)
{
        struct tm6000_IR *ir = rc->priv;

        if (!ir || !ir->int_urb)
                return;

        dprintk(2, "%s\n",__func__);

        usb_kill_urb(ir->int_urb);
        kfree(ir->int_urb->transfer_buffer);
        usb_free_urb(ir->int_urb);
        ir->int_urb = NULL;
}

int tm6000_ir_int_start(struct tm6000_core *dev)
{
        struct tm6000_IR *ir = dev->ir;

        if (!ir)
                return 0;

        return __tm6000_ir_int_start(ir->rc);
}

void tm6000_ir_int_stop(struct tm6000_core *dev)
{
        struct tm6000_IR *ir = dev->ir;

        if (!ir || !ir->rc)
                return;

        __tm6000_ir_int_stop(ir->rc);
}

int tm6000_ir_init(struct tm6000_core *dev)
{
        struct tm6000_IR *ir;
        struct rc_dev *rc;
        int err = -ENOMEM;
        u64 rc_proto;

        if (!enable_ir)
                return -ENODEV;

        if (!dev->caps.has_remote)
                return 0;

        if (!dev->ir_codes)
                return 0;

        ir = kzalloc(sizeof(*ir), GFP_ATOMIC);
        rc = rc_allocate_device(RC_DRIVER_SCANCODE);
        if (!ir || !rc)
                goto out;

        dprintk(2, "%s\n", __func__);

        /* record handles to ourself */
        ir->dev = dev;
        dev->ir = ir;
        ir->rc = rc;

        /* input setup */
        rc->allowed_protocols = RC_PROTO_BIT_RC5 | RC_PROTO_BIT_NEC;
        /* Needed, in order to support NEC remotes with 24 or 32 bits */
        rc->scancode_mask = 0xffff;
        rc->priv = ir;
        rc->change_protocol = tm6000_ir_change_protocol;
        if (dev->int_in.endp) {
                rc->open    = __tm6000_ir_int_start;
                rc->close   = __tm6000_ir_int_stop;
                INIT_DELAYED_WORK(&ir->work, tm6000_ir_int_work);
        } else {
                rc->open  = tm6000_ir_start;
                rc->close = tm6000_ir_stop;
                ir->polling = 50;
                INIT_DELAYED_WORK(&ir->work, tm6000_ir_handle_key);
        }

        snprintf(ir->name, sizeof(ir->name), "tm5600/60x0 IR (%s)",
                                                dev->name);

        usb_make_path(dev->udev, ir->phys, sizeof(ir->phys));
        strlcat(ir->phys, "/input0", sizeof(ir->phys));

        rc_proto = RC_PROTO_BIT_UNKNOWN;
        tm6000_ir_change_protocol(rc, &rc_proto);

        rc->device_name = ir->name;
        rc->input_phys = ir->phys;
        rc->input_id.bustype = BUS_USB;
        rc->input_id.version = 1;
        rc->input_id.vendor = le16_to_cpu(dev->udev->descriptor.idVendor);
        rc->input_id.product = le16_to_cpu(dev->udev->descriptor.idProduct);
        rc->map_name = dev->ir_codes;
        rc->driver_name = "tm6000";
        rc->dev.parent = &dev->udev->dev;

        /* ir register */
        err = rc_register_device(rc);
        if (err)
                goto out;

        return 0;

out:
        dev->ir = NULL;
        rc_free_device(rc);
        kfree(ir);
        return err;
}

int tm6000_ir_fini(struct tm6000_core *dev)
{
        struct tm6000_IR *ir = dev->ir;

        /* skip detach on non attached board */

        if (!ir)
                return 0;

        dprintk(2, "%s\n",__func__);

        if (!ir->polling)
                __tm6000_ir_int_stop(ir->rc);

        tm6000_ir_stop(ir->rc);

        /* Turn off the led */
        tm6000_flash_led(dev, 0);
        ir->pwled = 0;

        rc_unregister_device(ir->rc);

        kfree(ir);
        dev->ir = NULL;

        return 0;
}