/*
 * USB Driver for ALi m5602 based webcams
 *
 * Copyright (C) 2008 Erik Andrén
 * Copyright (C) 2007 Ilyes Gouta. Based on the m5603x Linux Driver Project.
 * Copyright (C) 2005 m5603x Linux Driver Project <m5602@x3ng.com.br>
 *
 * Portions of code to USB interface and ALi driver software,
 * Copyright (c) 2006 Willem Duinker
 * v4l2 interface modeled after the V4L2 driver
 * for SN9C10x PC Camera Controllers
 *
 * 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.
 *
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include "m5602_ov9650.h"
#include "m5602_ov7660.h"
#include "m5602_mt9m111.h"
#include "m5602_po1030.h"
#include "m5602_s5k83a.h"
#include "m5602_s5k4aa.h"

/* Kernel module parameters */
int force_sensor;
static bool dump_bridge;
bool dump_sensor;

static const struct usb_device_id m5602_table[] = {
        {USB_DEVICE(0x0402, 0x5602)},
        {}
};

MODULE_DEVICE_TABLE(usb, m5602_table);

/* Reads a byte from the m5602 */
int m5602_read_bridge(struct sd *sd, const u8 address, u8 *i2c_data)
{
        int err;
        struct usb_device *udev = sd->gspca_dev.dev;
        __u8 *buf = sd->gspca_dev.usb_buf;

        err = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
                              0x04, 0xc0, 0x14,
                              0x8100 + address, buf,
                              1, M5602_URB_MSG_TIMEOUT);
        *i2c_data = buf[0];

        PDEBUG(D_CONF, "Reading bridge register 0x%x containing 0x%x",
               address, *i2c_data);

        /* usb_control_msg(...) returns the number of bytes sent upon success,
        mask that and return zero instead*/
        return (err < 0) ? err : 0;
}

/* Writes a byte to the m5602 */
int m5602_write_bridge(struct sd *sd, const u8 address, const u8 i2c_data)
{
        int err;
        struct usb_device *udev = sd->gspca_dev.dev;
        __u8 *buf = sd->gspca_dev.usb_buf;

        PDEBUG(D_CONF, "Writing bridge register 0x%x with 0x%x",
               address, i2c_data);

        memcpy(buf, bridge_urb_skeleton,
               sizeof(bridge_urb_skeleton));
        buf[1] = address;
        buf[3] = i2c_data;

        err = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
                                0x04, 0x40, 0x19,
                                0x0000, buf,
                                4, M5602_URB_MSG_TIMEOUT);

        /* usb_control_msg(...) returns the number of bytes sent upon success,
           mask that and return zero instead */
        return (err < 0) ? err : 0;
}

static int m5602_wait_for_i2c(struct sd *sd)
{
        int err;
        u8 data;

        do {
                err = m5602_read_bridge(sd, M5602_XB_I2C_STATUS, &data);
        } while ((data & I2C_BUSY) && !err);
        return err;
}

int m5602_read_sensor(struct sd *sd, const u8 address,
                       u8 *i2c_data, const u8 len)
{
        int err, i;

        if (!len || len > sd->sensor->i2c_regW)
                return -EINVAL;

        err = m5602_wait_for_i2c(sd);
        if (err < 0)
                return err;

        err = m5602_write_bridge(sd, M5602_XB_I2C_DEV_ADDR,
                                 sd->sensor->i2c_slave_id);
        if (err < 0)
                return err;

        err = m5602_write_bridge(sd, M5602_XB_I2C_REG_ADDR, address);
        if (err < 0)
                return err;

        /* Sensors with registers that are of only
           one byte width are differently read */

        /* FIXME: This works with the ov9650, but has issues with the po1030 */
        if (sd->sensor->i2c_regW == 1) {
                err = m5602_write_bridge(sd, M5602_XB_I2C_CTRL, 1);
                if (err < 0)
                        return err;

                err = m5602_write_bridge(sd, M5602_XB_I2C_CTRL, 0x08);
        } else {
                err = m5602_write_bridge(sd, M5602_XB_I2C_CTRL, 0x18 + len);
        }

        for (i = 0; (i < len) && !err; i++) {
                err = m5602_wait_for_i2c(sd);
                if (err < 0)
                        return err;

                err = m5602_read_bridge(sd, M5602_XB_I2C_DATA, &(i2c_data[i]));

                PDEBUG(D_CONF, "Reading sensor register "
                               "0x%x containing 0x%x ", address, *i2c_data);
        }
        return err;
}

int m5602_write_sensor(struct sd *sd, const u8 address,
                        u8 *i2c_data, const u8 len)
{
        int err, i;
        u8 *p;
        struct usb_device *udev = sd->gspca_dev.dev;
        __u8 *buf = sd->gspca_dev.usb_buf;

        /* No sensor with a data width larger than 16 bits has yet been seen */
        if (len > sd->sensor->i2c_regW || !len)
                return -EINVAL;

        memcpy(buf, sensor_urb_skeleton,
               sizeof(sensor_urb_skeleton));

        buf[11] = sd->sensor->i2c_slave_id;
        buf[15] = address;

        /* Special case larger sensor writes */
        p = buf + 16;

        /* Copy a four byte write sequence for each byte to be written to */
        for (i = 0; i < len; i++) {
                memcpy(p, sensor_urb_skeleton + 16, 4);
                p[3] = i2c_data[i];
                p += 4;
                PDEBUG(D_CONF, "Writing sensor register 0x%x with 0x%x",
                       address, i2c_data[i]);
        }

        /* Copy the tailer */
        memcpy(p, sensor_urb_skeleton + 20, 4);

        /* Set the total length */
        p[3] = 0x10 + len;

        err = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
                              0x04, 0x40, 0x19,
                              0x0000, buf,
                              20 + len * 4, M5602_URB_MSG_TIMEOUT);

        return (err < 0) ? err : 0;
}

/* Dump all the registers of the m5602 bridge,
   unfortunately this breaks the camera until it's power cycled */
static void m5602_dump_bridge(struct sd *sd)
{
        int i;
        for (i = 0; i < 0x80; i++) {
                unsigned char val = 0;
                m5602_read_bridge(sd, i, &val);
                pr_info("ALi m5602 address 0x%x contains 0x%x\n", i, val);
        }
        pr_info("Warning: The ALi m5602 webcam probably won't work until it's power cycled\n");
}

static int m5602_probe_sensor(struct sd *sd)
{
        /* Try the po1030 */
        sd->sensor = &po1030;
        if (!sd->sensor->probe(sd))
                return 0;

        /* Try the mt9m111 sensor */
        sd->sensor = &mt9m111;
        if (!sd->sensor->probe(sd))
                return 0;

        /* Try the s5k4aa */
        sd->sensor = &s5k4aa;
        if (!sd->sensor->probe(sd))
                return 0;

        /* Try the ov9650 */
        sd->sensor = &ov9650;
        if (!sd->sensor->probe(sd))
                return 0;

        /* Try the ov7660 */
        sd->sensor = &ov7660;
        if (!sd->sensor->probe(sd))
                return 0;

        /* Try the s5k83a */
        sd->sensor = &s5k83a;
        if (!sd->sensor->probe(sd))
                return 0;

        /* More sensor probe function goes here */
        pr_info("Failed to find a sensor\n");
        sd->sensor = NULL;
        return -ENODEV;
}

static int m5602_configure(struct gspca_dev *gspca_dev,
                           const struct usb_device_id *id);

static int m5602_init(struct gspca_dev *gspca_dev)
{
        struct sd *sd = (struct sd *) gspca_dev;
        int err;

        PDEBUG(D_CONF, "Initializing ALi m5602 webcam");
        /* Run the init sequence */
        err = sd->sensor->init(sd);

        return err;
}

static int m5602_start_transfer(struct gspca_dev *gspca_dev)
{
        struct sd *sd = (struct sd *) gspca_dev;
        __u8 *buf = sd->gspca_dev.usb_buf;
        int err;

        /* Send start command to the camera */
        const u8 buffer[4] = {0x13, 0xf9, 0x0f, 0x01};

        if (sd->sensor->start)
                sd->sensor->start(sd);

        memcpy(buf, buffer, sizeof(buffer));
        err = usb_control_msg(gspca_dev->dev,
                              usb_sndctrlpipe(gspca_dev->dev, 0),
                              0x04, 0x40, 0x19, 0x0000, buf,
                              sizeof(buffer), M5602_URB_MSG_TIMEOUT);

        PDEBUG(D_STREAM, "Transfer started");
        return (err < 0) ? err : 0;
}

static void m5602_urb_complete(struct gspca_dev *gspca_dev,
                                u8 *data, int len)
{
        struct sd *sd = (struct sd *) gspca_dev;

        if (len < 6) {
                PDEBUG(D_PACK, "Packet is less than 6 bytes");
                return;
        }

        /* Frame delimiter: ff xx xx xx ff ff */
        if (data[0] == 0xff && data[4] == 0xff && data[5] == 0xff &&
            data[2] != sd->frame_id) {
                PDEBUG(D_FRAM, "Frame delimiter detected");
                sd->frame_id = data[2];

                /* Remove the extra fluff appended on each header */
                data += 6;
                len -= 6;

                /* Complete the last frame (if any) */
                gspca_frame_add(gspca_dev, LAST_PACKET,
                                NULL, 0);
                sd->frame_count++;

                /* Create a new frame */
                gspca_frame_add(gspca_dev, FIRST_PACKET, data, len);

                PDEBUG(D_FRAM, "Starting new frame %d",
                       sd->frame_count);

        } else {
                int cur_frame_len;

                cur_frame_len = gspca_dev->image_len;
                /* Remove urb header */
                data += 4;
                len -= 4;

                if (cur_frame_len + len <= gspca_dev->frsz) {
                        PDEBUG(D_FRAM, "Continuing frame %d copying %d bytes",
                               sd->frame_count, len);

                        gspca_frame_add(gspca_dev, INTER_PACKET,
                                        data, len);
                } else {
                        /* Add the remaining data up to frame size */
                        gspca_frame_add(gspca_dev, INTER_PACKET, data,
                                    gspca_dev->frsz - cur_frame_len);
                }
        }
}

static void m5602_stop_transfer(struct gspca_dev *gspca_dev)
{
        struct sd *sd = (struct sd *) gspca_dev;

        /* Run the sensor specific end transfer sequence */
        if (sd->sensor->stop)
                sd->sensor->stop(sd);
}

/* sub-driver description, the ctrl and nctrl is filled at probe time */
static struct sd_desc sd_desc = {
        .name           = MODULE_NAME,
        .config         = m5602_configure,
        .init           = m5602_init,
        .start          = m5602_start_transfer,
        .stopN          = m5602_stop_transfer,
        .pkt_scan       = m5602_urb_complete
};

/* this function is called at probe time */
static int m5602_configure(struct gspca_dev *gspca_dev,
                           const struct usb_device_id *id)
{
        struct sd *sd = (struct sd *) gspca_dev;
        struct cam *cam;
        int err;

        cam = &gspca_dev->cam;
        sd->desc = &sd_desc;

        if (dump_bridge)
                m5602_dump_bridge(sd);

        /* Probe sensor */
        err = m5602_probe_sensor(sd);
        if (err)
                goto fail;

        return 0;

fail:
        PDEBUG(D_ERR, "ALi m5602 webcam failed");
        cam->cam_mode = NULL;
        cam->nmodes = 0;

        return err;
}

static int m5602_probe(struct usb_interface *intf,
                       const struct usb_device_id *id)
{
        return gspca_dev_probe(intf, id, &sd_desc, sizeof(struct sd),
                               THIS_MODULE);
}

static void m5602_disconnect(struct usb_interface *intf)
{
        struct gspca_dev *gspca_dev = usb_get_intfdata(intf);
        struct sd *sd = (struct sd *) gspca_dev;

        if (sd->sensor->disconnect)
                sd->sensor->disconnect(sd);

        gspca_disconnect(intf);
}

static struct usb_driver sd_driver = {
        .name = MODULE_NAME,
        .id_table = m5602_table,
        .probe = m5602_probe,
#ifdef CONFIG_PM
        .suspend = gspca_suspend,
        .resume = gspca_resume,
#endif
        .disconnect = m5602_disconnect
};

module_usb_driver(sd_driver);

MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");
module_param(force_sensor, int, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(force_sensor,
                "forces detection of a sensor, "
                "1 = OV9650, 2 = S5K83A, 3 = S5K4AA, "
                "4 = MT9M111, 5 = PO1030, 6 = OV7660");

module_param(dump_bridge, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(dump_bridge, "Dumps all usb bridge registers at startup");

module_param(dump_sensor, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(dump_sensor, "Dumps all usb sensor registers "
                "at startup providing a sensor is found");