/*
 * Driver for the s5k83a sensor
 *
 * 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 <linux/kthread.h>
#include "m5602_s5k83a.h"

static int s5k83a_set_gain(struct gspca_dev *gspca_dev, __s32 val);
static int s5k83a_get_gain(struct gspca_dev *gspca_dev, __s32 *val);
static int s5k83a_set_brightness(struct gspca_dev *gspca_dev, __s32 val);
static int s5k83a_get_brightness(struct gspca_dev *gspca_dev, __s32 *val);
static int s5k83a_set_exposure(struct gspca_dev *gspca_dev, __s32 val);
static int s5k83a_get_exposure(struct gspca_dev *gspca_dev, __s32 *val);
static int s5k83a_get_vflip(struct gspca_dev *gspca_dev, __s32 *val);
static int s5k83a_set_vflip(struct gspca_dev *gspca_dev, __s32 val);
static int s5k83a_get_hflip(struct gspca_dev *gspca_dev, __s32 *val);
static int s5k83a_set_hflip(struct gspca_dev *gspca_dev, __s32 val);

static struct v4l2_pix_format s5k83a_modes[] = {
	{
		640,
		480,
		V4L2_PIX_FMT_SBGGR8,
		V4L2_FIELD_NONE,
		.sizeimage =
			640 * 480,
		.bytesperline = 640,
		.colorspace = V4L2_COLORSPACE_SRGB,
		.priv = 0
	}
};

static const struct ctrl s5k83a_ctrls[] = {
#define GAIN_IDX 0
	{
		{
			.id = V4L2_CID_GAIN,
			.type = V4L2_CTRL_TYPE_INTEGER,
			.name = "gain",
			.minimum = 0x00,
			.maximum = 0xff,
			.step = 0x01,
			.default_value = S5K83A_DEFAULT_GAIN,
			.flags = V4L2_CTRL_FLAG_SLIDER
		},
			.set = s5k83a_set_gain,
			.get = s5k83a_get_gain

	},
#define BRIGHTNESS_IDX 1
	{
		{
			.id = V4L2_CID_BRIGHTNESS,
			.type = V4L2_CTRL_TYPE_INTEGER,
			.name = "brightness",
			.minimum = 0x00,
			.maximum = 0xff,
			.step = 0x01,
			.default_value = S5K83A_DEFAULT_BRIGHTNESS,
			.flags = V4L2_CTRL_FLAG_SLIDER
		},
			.set = s5k83a_set_brightness,
			.get = s5k83a_get_brightness,
	},
#define EXPOSURE_IDX 2
	{
		{
			.id = V4L2_CID_EXPOSURE,
			.type = V4L2_CTRL_TYPE_INTEGER,
			.name = "exposure",
			.minimum = 0x00,
			.maximum = S5K83A_MAXIMUM_EXPOSURE,
			.step = 0x01,
			.default_value = S5K83A_DEFAULT_EXPOSURE,
			.flags = V4L2_CTRL_FLAG_SLIDER
		},
			.set = s5k83a_set_exposure,
			.get = s5k83a_get_exposure
	},
#define HFLIP_IDX 3
	{
		{
			.id = V4L2_CID_HFLIP,
			.type = V4L2_CTRL_TYPE_BOOLEAN,
			.name = "horizontal flip",
			.minimum = 0,
			.maximum = 1,
			.step = 1,
			.default_value = 0
		},
			.set = s5k83a_set_hflip,
			.get = s5k83a_get_hflip
	},
#define VFLIP_IDX 4
	{
		{
			.id = V4L2_CID_VFLIP,
			.type = V4L2_CTRL_TYPE_BOOLEAN,
			.name = "vertical flip",
			.minimum = 0,
			.maximum = 1,
			.step = 1,
			.default_value = 0
		},
		.set = s5k83a_set_vflip,
		.get = s5k83a_get_vflip
	}
};

static void s5k83a_dump_registers(struct sd *sd);
static int s5k83a_get_rotation(struct sd *sd, u8 *reg_data);
static int s5k83a_set_led_indication(struct sd *sd, u8 val);
static int s5k83a_set_flip_real(struct gspca_dev *gspca_dev,
				__s32 vflip, __s32 hflip);

int s5k83a_probe(struct sd *sd)
{
	struct s5k83a_priv *sens_priv;
	u8 prod_id = 0, ver_id = 0;
	int i, err = 0;

	if (force_sensor) {
		if (force_sensor == S5K83A_SENSOR) {
			pr_info("Forcing a %s sensor\n", s5k83a.name);
			goto sensor_found;
		}
		/* If we want to force another sensor, don't try to probe this
		 * one */
		return -ENODEV;
	}

	PDEBUG(D_PROBE, "Probing for a s5k83a sensor");

	/* Preinit the sensor */
	for (i = 0; i < ARRAY_SIZE(preinit_s5k83a) && !err; i++) {
		u8 data[2] = {preinit_s5k83a[i][2], preinit_s5k83a[i][3]};
		if (preinit_s5k83a[i][0] == SENSOR)
			err = m5602_write_sensor(sd, preinit_s5k83a[i][1],
				data, 2);
		else
			err = m5602_write_bridge(sd, preinit_s5k83a[i][1],
				data[0]);
	}

	/* We don't know what register (if any) that contain the product id
	 * Just pick the first addresses that seem to produce the same results
	 * on multiple machines */
	if (m5602_read_sensor(sd, 0x00, &prod_id, 1))
		return -ENODEV;

	if (m5602_read_sensor(sd, 0x01, &ver_id, 1))
		return -ENODEV;

	if ((prod_id == 0xff) || (ver_id == 0xff))
		return -ENODEV;
	else
		pr_info("Detected a s5k83a sensor\n");

sensor_found:
	sens_priv = kmalloc(
		sizeof(struct s5k83a_priv), GFP_KERNEL);
	if (!sens_priv)
		return -ENOMEM;

	sens_priv->settings =
	kmalloc(sizeof(s32)*ARRAY_SIZE(s5k83a_ctrls), GFP_KERNEL);
	if (!sens_priv->settings) {
		kfree(sens_priv);
		return -ENOMEM;
	}

	sd->gspca_dev.cam.cam_mode = s5k83a_modes;
	sd->gspca_dev.cam.nmodes = ARRAY_SIZE(s5k83a_modes);
	sd->desc->ctrls = s5k83a_ctrls;
	sd->desc->nctrls = ARRAY_SIZE(s5k83a_ctrls);

	/* null the pointer! thread is't running now */
	sens_priv->rotation_thread = NULL;

	for (i = 0; i < ARRAY_SIZE(s5k83a_ctrls); i++)
		sens_priv->settings[i] = s5k83a_ctrls[i].qctrl.default_value;

	sd->sensor_priv = sens_priv;
	return 0;
}

int s5k83a_init(struct sd *sd)
{
	int i, err = 0;
	s32 *sensor_settings =
			((struct s5k83a_priv *) sd->sensor_priv)->settings;

	for (i = 0; i < ARRAY_SIZE(init_s5k83a) && !err; i++) {
		u8 data[2] = {0x00, 0x00};

		switch (init_s5k83a[i][0]) {
		case BRIDGE:
			err = m5602_write_bridge(sd,
					init_s5k83a[i][1],
					init_s5k83a[i][2]);
			break;

		case SENSOR:
			data[0] = init_s5k83a[i][2];
			err = m5602_write_sensor(sd,
				init_s5k83a[i][1], data, 1);
			break;

		case SENSOR_LONG:
			data[0] = init_s5k83a[i][2];
			data[1] = init_s5k83a[i][3];
			err = m5602_write_sensor(sd,
				init_s5k83a[i][1], data, 2);
			break;
		default:
			pr_info("Invalid stream command, exiting init\n");
			return -EINVAL;
		}
	}

	if (dump_sensor)
		s5k83a_dump_registers(sd);

	err = s5k83a_set_gain(&sd->gspca_dev, sensor_settings[GAIN_IDX]);
	if (err < 0)
		return err;

	err = s5k83a_set_brightness(&sd->gspca_dev,
				     sensor_settings[BRIGHTNESS_IDX]);
	if (err < 0)
		return err;

	err = s5k83a_set_exposure(&sd->gspca_dev,
				   sensor_settings[EXPOSURE_IDX]);
	if (err < 0)
		return err;

	err = s5k83a_set_hflip(&sd->gspca_dev, sensor_settings[HFLIP_IDX]);
	if (err < 0)
		return err;

	err = s5k83a_set_vflip(&sd->gspca_dev, sensor_settings[VFLIP_IDX]);

	return err;
}

static int rotation_thread_function(void *data)
{
	struct sd *sd = (struct sd *) data;
	struct s5k83a_priv *sens_priv = sd->sensor_priv;
	u8 reg, previous_rotation = 0;
	__s32 vflip, hflip;

	set_current_state(TASK_INTERRUPTIBLE);
	while (!schedule_timeout(100)) {
		if (mutex_lock_interruptible(&sd->gspca_dev.usb_lock))
			break;

		s5k83a_get_rotation(sd, &reg);
		if (previous_rotation != reg) {
			previous_rotation = reg;
			pr_info("Camera was flipped\n");

			s5k83a_get_vflip((struct gspca_dev *) sd, &vflip);
			s5k83a_get_hflip((struct gspca_dev *) sd, &hflip);

			if (reg) {
				vflip = !vflip;
				hflip = !hflip;
			}
			s5k83a_set_flip_real((struct gspca_dev *) sd,
					      vflip, hflip);
		}

		mutex_unlock(&sd->gspca_dev.usb_lock);
		set_current_state(TASK_INTERRUPTIBLE);
	}

	/* return to "front" flip */
	if (previous_rotation) {
		s5k83a_get_vflip((struct gspca_dev *) sd, &vflip);
		s5k83a_get_hflip((struct gspca_dev *) sd, &hflip);
		s5k83a_set_flip_real((struct gspca_dev *) sd, vflip, hflip);
	}

	sens_priv->rotation_thread = NULL;
	return 0;
}

int s5k83a_start(struct sd *sd)
{
	int i, err = 0;
	struct s5k83a_priv *sens_priv = sd->sensor_priv;

	/* Create another thread, polling the GPIO ports of the camera to check
	   if it got rotated. This is how the windows driver does it so we have
	   to assume that there is no better way of accomplishing this */
	sens_priv->rotation_thread = kthread_create(rotation_thread_function,
						    sd, "rotation thread");
	wake_up_process(sens_priv->rotation_thread);

	/* Preinit the sensor */
	for (i = 0; i < ARRAY_SIZE(start_s5k83a) && !err; i++) {
		u8 data[2] = {start_s5k83a[i][2], start_s5k83a[i][3]};
		if (start_s5k83a[i][0] == SENSOR)
			err = m5602_write_sensor(sd, start_s5k83a[i][1],
				data, 2);
		else
			err = m5602_write_bridge(sd, start_s5k83a[i][1],
				data[0]);
	}
	if (err < 0)
		return err;

	return s5k83a_set_led_indication(sd, 1);
}

int s5k83a_stop(struct sd *sd)
{
	struct s5k83a_priv *sens_priv = sd->sensor_priv;

	if (sens_priv->rotation_thread)
		kthread_stop(sens_priv->rotation_thread);

	return s5k83a_set_led_indication(sd, 0);
}

void s5k83a_disconnect(struct sd *sd)
{
	struct s5k83a_priv *sens_priv = sd->sensor_priv;

	s5k83a_stop(sd);

	sd->sensor = NULL;
	kfree(sens_priv->settings);
	kfree(sens_priv);
}

static int s5k83a_get_gain(struct gspca_dev *gspca_dev, __s32 *val)
{
	struct sd *sd = (struct sd *) gspca_dev;
	struct s5k83a_priv *sens_priv = sd->sensor_priv;

	*val = sens_priv->settings[GAIN_IDX];
	return 0;
}

static int s5k83a_set_gain(struct gspca_dev *gspca_dev, __s32 val)
{
	int err;
	u8 data[2];
	struct sd *sd = (struct sd *) gspca_dev;
	struct s5k83a_priv *sens_priv = sd->sensor_priv;

	sens_priv->settings[GAIN_IDX] = val;

	data[0] = 0x00;
	data[1] = 0x20;
	err = m5602_write_sensor(sd, 0x14, data, 2);
	if (err < 0)
		return err;

	data[0] = 0x01;
	data[1] = 0x00;
	err = m5602_write_sensor(sd, 0x0d, data, 2);
	if (err < 0)
		return err;

	/* FIXME: This is not sane, we need to figure out the composition
		  of these registers */
	data[0] = val >> 3; /* gain, high 5 bits */
	data[1] = val >> 1; /* gain, high 7 bits */
	err = m5602_write_sensor(sd, S5K83A_GAIN, data, 2);

	return err;
}

static int s5k83a_get_brightness(struct gspca_dev *gspca_dev, __s32 *val)
{
	struct sd *sd = (struct sd *) gspca_dev;
	struct s5k83a_priv *sens_priv = sd->sensor_priv;

	*val = sens_priv->settings[BRIGHTNESS_IDX];
	return 0;
}

static int s5k83a_set_brightness(struct gspca_dev *gspca_dev, __s32 val)
{
	int err;
	u8 data[1];
	struct sd *sd = (struct sd *) gspca_dev;
	struct s5k83a_priv *sens_priv = sd->sensor_priv;

	sens_priv->settings[BRIGHTNESS_IDX] = val;
	data[0] = val;
	err = m5602_write_sensor(sd, S5K83A_BRIGHTNESS, data, 1);
	return err;
}

static int s5k83a_get_exposure(struct gspca_dev *gspca_dev, __s32 *val)
{
	struct sd *sd = (struct sd *) gspca_dev;
	struct s5k83a_priv *sens_priv = sd->sensor_priv;

	*val = sens_priv->settings[EXPOSURE_IDX];
	return 0;
}

static int s5k83a_set_exposure(struct gspca_dev *gspca_dev, __s32 val)
{
	int err;
	u8 data[2];
	struct sd *sd = (struct sd *) gspca_dev;
	struct s5k83a_priv *sens_priv = sd->sensor_priv;

	sens_priv->settings[EXPOSURE_IDX] = val;
	data[0] = 0;
	data[1] = val;
	err = m5602_write_sensor(sd, S5K83A_EXPOSURE, data, 2);
	return err;
}

static int s5k83a_get_vflip(struct gspca_dev *gspca_dev, __s32 *val)
{
	struct sd *sd = (struct sd *) gspca_dev;
	struct s5k83a_priv *sens_priv = sd->sensor_priv;

	*val = sens_priv->settings[VFLIP_IDX];
	return 0;
}

static int s5k83a_set_flip_real(struct gspca_dev *gspca_dev,
				__s32 vflip, __s32 hflip)
{
	int err;
	u8 data[1];
	struct sd *sd = (struct sd *) gspca_dev;

	data[0] = 0x05;
	err = m5602_write_sensor(sd, S5K83A_PAGE_MAP, data, 1);
	if (err < 0)
		return err;

	/* six bit is vflip, seven is hflip */
	data[0] = S5K83A_FLIP_MASK;
	data[0] = (vflip) ? data[0] | 0x40 : data[0];
	data[0] = (hflip) ? data[0] | 0x80 : data[0];

	err = m5602_write_sensor(sd, S5K83A_FLIP, data, 1);
	if (err < 0)
		return err;

	data[0] = (vflip) ? 0x0b : 0x0a;
	err = m5602_write_sensor(sd, S5K83A_VFLIP_TUNE, data, 1);
	if (err < 0)
		return err;

	data[0] = (hflip) ? 0x0a : 0x0b;
	err = m5602_write_sensor(sd, S5K83A_HFLIP_TUNE, data, 1);
	return err;
}

static int s5k83a_set_vflip(struct gspca_dev *gspca_dev, __s32 val)
{
	int err;
	u8 reg;
	__s32 hflip;
	struct sd *sd = (struct sd *) gspca_dev;
	struct s5k83a_priv *sens_priv = sd->sensor_priv;

	sens_priv->settings[VFLIP_IDX] = val;

	s5k83a_get_hflip(gspca_dev, &hflip);

	err = s5k83a_get_rotation(sd, &reg);
	if (err < 0)
		return err;
	if (reg) {
		val = !val;
		hflip = !hflip;
	}

	err = s5k83a_set_flip_real(gspca_dev, val, hflip);
	return err;
}

static int s5k83a_get_hflip(struct gspca_dev *gspca_dev, __s32 *val)
{
	struct sd *sd = (struct sd *) gspca_dev;
	struct s5k83a_priv *sens_priv = sd->sensor_priv;

	*val = sens_priv->settings[HFLIP_IDX];
	return 0;
}

static int s5k83a_set_hflip(struct gspca_dev *gspca_dev, __s32 val)
{
	int err;
	u8 reg;
	__s32 vflip;
	struct sd *sd = (struct sd *) gspca_dev;
	struct s5k83a_priv *sens_priv = sd->sensor_priv;

	sens_priv->settings[HFLIP_IDX] = val;

	s5k83a_get_vflip(gspca_dev, &vflip);

	err = s5k83a_get_rotation(sd, &reg);
	if (err < 0)
		return err;
	if (reg) {
		val = !val;
		vflip = !vflip;
	}

	err = s5k83a_set_flip_real(gspca_dev, vflip, val);
	return err;
}

static int s5k83a_set_led_indication(struct sd *sd, u8 val)
{
	int err = 0;
	u8 data[1];

	err = m5602_read_bridge(sd, M5602_XB_GPIO_DAT, data);
	if (err < 0)
		return err;

	if (val)
		data[0] = data[0] | S5K83A_GPIO_LED_MASK;
	else
		data[0] = data[0] & ~S5K83A_GPIO_LED_MASK;

	err = m5602_write_bridge(sd, M5602_XB_GPIO_DAT, data[0]);

	return err;
}

/* Get camera rotation on Acer notebooks */
static int s5k83a_get_rotation(struct sd *sd, u8 *reg_data)
{
	int err = m5602_read_bridge(sd, M5602_XB_GPIO_DAT, reg_data);
	*reg_data = (*reg_data & S5K83A_GPIO_ROTATION_MASK) ? 0 : 1;
	return err;
}

static void s5k83a_dump_registers(struct sd *sd)
{
	int address;
	u8 page, old_page;
	m5602_read_sensor(sd, S5K83A_PAGE_MAP, &old_page, 1);

	for (page = 0; page < 16; page++) {
		m5602_write_sensor(sd, S5K83A_PAGE_MAP, &page, 1);
		pr_info("Dumping the s5k83a register state for page 0x%x\n",
			page);
		for (address = 0; address <= 0xff; address++) {
			u8 val = 0;
			m5602_read_sensor(sd, address, &val, 1);
			pr_info("register 0x%x contains 0x%x\n", address, val);
		}
	}
	pr_info("s5k83a register state dump complete\n");

	for (page = 0; page < 16; page++) {
		m5602_write_sensor(sd, S5K83A_PAGE_MAP, &page, 1);
		pr_info("Probing for which registers that are read/write for page 0x%x\n",
			page);
		for (address = 0; address <= 0xff; address++) {
			u8 old_val, ctrl_val, test_val = 0xff;

			m5602_read_sensor(sd, address, &old_val, 1);
			m5602_write_sensor(sd, address, &test_val, 1);
			m5602_read_sensor(sd, address, &ctrl_val, 1);

			if (ctrl_val == test_val)
				pr_info("register 0x%x is writeable\n",
					address);
			else
				pr_info("register 0x%x is read only\n",
					address);

			/* Restore original val */
			m5602_write_sensor(sd, address, &old_val, 1);
		}
	}
	pr_info("Read/write register probing complete\n");
	m5602_write_sensor(sd, S5K83A_PAGE_MAP, &old_page, 1);
}