[media] Add v4l2 subdev driver for S5K4ECGX sensor

This patch adds driver for Samsung S5K4ECGX image sensor with an
embedded SoC ISP. The driver only implements preview operation mode
and still capture (snapshot) and face detection features are missing
now. Following controls are supported: contrast, saturation,
brightness, sharpness.

Signed-off-by: Sangwook Lee <sangwook.lee@linaro.org>
Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

3 files changed, 1044 insertions, 0 deletions

diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
index d3be0ca27361..24d78e28e493 100644
--- a/drivers/media/i2c/Kconfig
+++ b/drivers/media/i2c/Kconfig
@@ -507,6 +507,13 @@ config VIDEO_S5K6AA
 	  This is a V4L2 sensor-level driver for Samsung S5K6AA(FX) 1.3M
 	  camera sensor with an embedded SoC image signal processor.
 
+config VIDEO_S5K4ECGX
+        tristate "Samsung S5K4ECGX sensor support"
+        depends on I2C && VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API
+        ---help---
+          This is a V4L2 sensor-level driver for Samsung S5K4ECGX 5M
+          camera sensor with an embedded SoC image signal processor.
+
 source "drivers/media/i2c/smiapp/Kconfig"
 
 comment "Flash devices"
diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile
index 4a270f7983de..b1d62dfd49b8 100644
--- a/drivers/media/i2c/Makefile
+++ b/drivers/media/i2c/Makefile
@@ -57,6 +57,7 @@ obj-$(CONFIG_VIDEO_MT9V032) += mt9v032.o
 obj-$(CONFIG_VIDEO_SR030PC30)	+= sr030pc30.o
 obj-$(CONFIG_VIDEO_NOON010PC30)	+= noon010pc30.o
 obj-$(CONFIG_VIDEO_S5K6AA)	+= s5k6aa.o
+obj-$(CONFIG_VIDEO_S5K4ECGX)	+= s5k4ecgx.o
 obj-$(CONFIG_VIDEO_ADP1653)	+= adp1653.o
 obj-$(CONFIG_VIDEO_AS3645A)	+= as3645a.o
 obj-$(CONFIG_VIDEO_SMIAPP_PLL)	+= smiapp-pll.o
diff --git a/drivers/media/i2c/s5k4ecgx.c b/drivers/media/i2c/s5k4ecgx.c
new file mode 100644
index 000000000000..49c1b3abb425
--- /dev/null
+++ b/drivers/media/i2c/s5k4ecgx.c
@@ -0,0 +1,1036 @@
+/*
+ * Driver for Samsung S5K4ECGX 1/4" 5Mp CMOS Image Sensor SoC
+ * with an Embedded Image Signal Processor.
+ *
+ * Copyright (C) 2012, Linaro, Sangwook Lee <sangwook.lee@linaro.org>
+ * Copyright (C) 2012, Insignal Co,. Ltd, Homin Lee <suapapa@insignal.co.kr>
+ *
+ * Based on s5k6aa and noon010pc30 driver
+ * Copyright (C) 2011, Samsung Electronics Co., Ltd.
+ *
+ * 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.
+ */
+
+#include <linux/clk.h>
+#include <linux/crc32.h>
+#include <linux/ctype.h>
+#include <linux/delay.h>
+#include <linux/firmware.h>
+#include <linux/gpio.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/regulator/consumer.h>
+#include <linux/slab.h>
+#include <asm/unaligned.h>
+
+#include <media/media-entity.h>
+#include <media/s5k4ecgx.h>
+#include <media/v4l2-ctrls.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-mediabus.h>
+#include <media/v4l2-subdev.h>
+
+static int debug;
+module_param(debug, int, 0644);
+
+#define S5K4ECGX_DRIVER_NAME		"s5k4ecgx"
+#define S5K4ECGX_FIRMWARE		"s5k4ecgx.bin"
+
+/* Firmware revision information */
+#define REG_FW_REVISION			0x700001a6
+#define REG_FW_VERSION			0x700001a4
+#define S5K4ECGX_REVISION_1_1		0x11
+#define S5K4ECGX_FW_VERSION		0x4ec0
+
+/* General purpose parameters */
+#define REG_USER_BRIGHTNESS		0x7000022c
+#define REG_USER_CONTRAST		0x7000022e
+#define REG_USER_SATURATION		0x70000230
+
+#define REG_G_ENABLE_PREV		0x7000023e
+#define REG_G_ENABLE_PREV_CHG		0x70000240
+#define REG_G_NEW_CFG_SYNC		0x7000024a
+#define REG_G_PREV_IN_WIDTH		0x70000250
+#define REG_G_PREV_IN_HEIGHT		0x70000252
+#define REG_G_PREV_IN_XOFFS		0x70000254
+#define REG_G_PREV_IN_YOFFS		0x70000256
+#define REG_G_CAP_IN_WIDTH		0x70000258
+#define REG_G_CAP_IN_HEIGHT		0x7000025a
+#define REG_G_CAP_IN_XOFFS		0x7000025c
+#define REG_G_CAP_IN_YOFFS		0x7000025e
+#define REG_G_INPUTS_CHANGE_REQ		0x70000262
+#define REG_G_ACTIVE_PREV_CFG		0x70000266
+#define REG_G_PREV_CFG_CHG		0x70000268
+#define REG_G_PREV_OPEN_AFTER_CH	0x7000026a
+
+/* Preview context register sets. n = 0...4. */
+#define PREG(n, x)			((n) * 0x30 + (x))
+#define REG_P_OUT_WIDTH(n)		PREG(n, 0x700002a6)
+#define REG_P_OUT_HEIGHT(n)		PREG(n, 0x700002a8)
+#define REG_P_FMT(n)			PREG(n, 0x700002aa)
+#define REG_P_PVI_MASK(n)		PREG(n, 0x700002b4)
+#define REG_P_FR_TIME_TYPE(n)		PREG(n, 0x700002be)
+#define  FR_TIME_DYNAMIC		0
+#define  FR_TIME_FIXED			1
+#define  FR_TIME_FIXED_ACCURATE		2
+#define REG_P_FR_TIME_Q_TYPE(n)		PREG(n, 0x700002c0)
+#define  FR_TIME_Q_DYNAMIC		0
+#define  FR_TIME_Q_BEST_FRRATE		1
+#define  FR_TIME_Q_BEST_QUALITY		2
+
+/* Frame period in 0.1 ms units */
+#define REG_P_MAX_FR_TIME(n)		PREG(n, 0x700002c2)
+#define REG_P_MIN_FR_TIME(n)		PREG(n, 0x700002c4)
+#define  US_TO_FR_TIME(__t)		((__t) / 100)
+#define REG_P_PREV_MIRROR(n)		PREG(n, 0x700002d0)
+#define REG_P_CAP_MIRROR(n)		PREG(n, 0x700002d2)
+
+#define REG_G_PREVZOOM_IN_WIDTH		0x70000494
+#define REG_G_PREVZOOM_IN_HEIGHT	0x70000496
+#define REG_G_PREVZOOM_IN_XOFFS		0x70000498
+#define REG_G_PREVZOOM_IN_YOFFS		0x7000049a
+#define REG_G_CAPZOOM_IN_WIDTH		0x7000049c
+#define REG_G_CAPZOOM_IN_HEIGHT		0x7000049e
+#define REG_G_CAPZOOM_IN_XOFFS		0x700004a0
+#define REG_G_CAPZOOM_IN_YOFFS		0x700004a2
+
+/* n = 0...4 */
+#define REG_USER_SHARPNESS(n)		(0x70000a28 + (n) * 0xb6)
+
+/* Reduce sharpness range for user space API */
+#define SHARPNESS_DIV			8208
+#define TOK_TERM			0xffffffff
+
+/*
+ * FIXME: This is copied from s5k6aa, because of no information
+ * in the S5K4ECGX datasheet.
+ * H/W register Interface (0xd0000000 - 0xd0000fff)
+ */
+#define AHB_MSB_ADDR_PTR		0xfcfc
+#define GEN_REG_OFFSH			0xd000
+#define REG_CMDWR_ADDRH			0x0028
+#define REG_CMDWR_ADDRL			0x002a
+#define REG_CMDRD_ADDRH			0x002c
+#define REG_CMDRD_ADDRL			0x002e
+#define REG_CMDBUF0_ADDR		0x0f12
+
+struct s5k4ecgx_frmsize {
+	struct v4l2_frmsize_discrete size;
+	/* Fixed sensor matrix crop rectangle */
+	struct v4l2_rect input_window;
+};
+
+struct regval_list {
+	u32 addr;
+	u16 val;
+};
+
+/*
+ * TODO: currently only preview is supported and snapshot (capture)
+ * is not implemented yet
+ */
+static const struct s5k4ecgx_frmsize s5k4ecgx_prev_sizes[] = {
+	{
+		.size = { 176, 144 },
+		.input_window = { 0x00, 0x00, 0x928, 0x780 },
+	}, {
+		.size = { 352, 288 },
+		.input_window = { 0x00, 0x00, 0x928, 0x780 },
+	}, {
+		.size = { 640, 480 },
+		.input_window = { 0x00, 0x00, 0xa00, 0x780 },
+	}, {
+		.size = { 720, 480 },
+		.input_window = { 0x00, 0x00, 0xa00, 0x6a8 },
+	}
+};
+
+#define S5K4ECGX_NUM_PREV ARRAY_SIZE(s5k4ecgx_prev_sizes)
+
+struct s5k4ecgx_pixfmt {
+	enum v4l2_mbus_pixelcode code;
+	u32 colorspace;
+	/* REG_TC_PCFG_Format register value */
+	u16 reg_p_format;
+};
+
+/* By default value, output from sensor will be YUV422 0-255 */
+static const struct s5k4ecgx_pixfmt s5k4ecgx_formats[] = {
+	{ V4L2_MBUS_FMT_YUYV8_2X8, V4L2_COLORSPACE_JPEG, 5 },
+};
+
+static const char * const s5k4ecgx_supply_names[] = {
+	/*
+	 * Usually 2.8V is used for analog power (vdda)
+	 * and digital IO (vddio, vdddcore)
+	 */
+	"vdda",
+	"vddio",
+	"vddcore",
+	"vddreg", /* The internal s5k4ecgx regulator's supply (1.8V) */
+};
+
+#define S5K4ECGX_NUM_SUPPLIES ARRAY_SIZE(s5k4ecgx_supply_names)
+
+enum s5k4ecgx_gpio_id {
+	STBY,
+	RST,
+	GPIO_NUM,
+};
+
+struct s5k4ecgx {
+	struct v4l2_subdev sd;
+	struct media_pad pad;
+	struct v4l2_ctrl_handler handler;
+
+	struct s5k4ecgx_platform_data *pdata;
+	const struct s5k4ecgx_pixfmt *curr_pixfmt;
+	const struct s5k4ecgx_frmsize *curr_frmsize;
+	struct mutex lock;
+	u8 streaming;
+	u8 set_params;
+
+	struct regulator_bulk_data supplies[S5K4ECGX_NUM_SUPPLIES];
+	struct s5k4ecgx_gpio gpio[GPIO_NUM];
+};
+
+static inline struct s5k4ecgx *to_s5k4ecgx(struct v4l2_subdev *sd)
+{
+	return container_of(sd, struct s5k4ecgx, sd);
+}
+
+static int s5k4ecgx_i2c_read(struct i2c_client *client, u16 addr, u16 *val)
+{
+	u8 wbuf[2] = { addr >> 8, addr & 0xff };
+	struct i2c_msg msg[2];
+	u8 rbuf[2];
+	int ret;
+
+	msg[0].addr = client->addr;
+	msg[0].flags = 0;
+	msg[0].len = 2;
+	msg[0].buf = wbuf;
+
+	msg[1].addr = client->addr;
+	msg[1].flags = I2C_M_RD;
+	msg[1].len = 2;
+	msg[1].buf = rbuf;
+
+	ret = i2c_transfer(client->adapter, msg, 2);
+	*val = be16_to_cpu(*((u16 *)rbuf));
+
+	v4l2_dbg(4, debug, client, "i2c_read: 0x%04X : 0x%04x\n", addr, *val);
+
+	return ret == 2 ? 0 : ret;
+}
+
+static int s5k4ecgx_i2c_write(struct i2c_client *client, u16 addr, u16 val)
+{
+	u8 buf[4] = { addr >> 8, addr & 0xff, val >> 8, val & 0xff };
+
+	int ret = i2c_master_send(client, buf, 4);
+	v4l2_dbg(4, debug, client, "i2c_write: 0x%04x : 0x%04x\n", addr, val);
+
+	return ret == 4 ? 0 : ret;
+}
+
+static int s5k4ecgx_write(struct i2c_client *client, u32 addr, u16 val)
+{
+	u16 high = addr >> 16, low = addr & 0xffff;
+	int ret;
+
+	v4l2_dbg(3, debug, client, "write: 0x%08x : 0x%04x\n", addr, val);
+
+	ret = s5k4ecgx_i2c_write(client, REG_CMDWR_ADDRH, high);
+	if (!ret)
+		ret = s5k4ecgx_i2c_write(client, REG_CMDWR_ADDRL, low);
+	if (!ret)
+		ret = s5k4ecgx_i2c_write(client, REG_CMDBUF0_ADDR, val);
+
+	return ret;
+}
+
+static int s5k4ecgx_read(struct i2c_client *client, u32 addr, u16 *val)
+{
+	u16 high = addr >> 16, low =  addr & 0xffff;
+	int ret;
+
+	ret = s5k4ecgx_i2c_write(client, REG_CMDRD_ADDRH, high);
+	if (!ret)
+		ret = s5k4ecgx_i2c_write(client, REG_CMDRD_ADDRL, low);
+	if (!ret)
+		ret = s5k4ecgx_i2c_read(client, REG_CMDBUF0_ADDR, val);
+	if (!ret)
+		dev_err(&client->dev, "Failed to execute read command\n");
+
+	return ret;
+}
+
+static int s5k4ecgx_read_fw_ver(struct v4l2_subdev *sd)
+{
+	struct i2c_client *client = v4l2_get_subdevdata(sd);
+	u16 hw_rev, fw_ver = 0;
+	int ret;
+
+	ret = s5k4ecgx_read(client, REG_FW_VERSION, &fw_ver);
+	if (ret < 0 || fw_ver != S5K4ECGX_FW_VERSION) {
+		v4l2_err(sd, "FW version check failed!\n");
+		return -ENODEV;
+	}
+
+	ret = s5k4ecgx_read(client, REG_FW_REVISION, &hw_rev);
+	if (ret < 0)
+		return ret;
+
+	v4l2_info(sd, "chip found FW ver: 0x%x, HW rev: 0x%x\n",
+						fw_ver, hw_rev);
+	return 0;
+}
+
+static int s5k4ecgx_set_ahb_address(struct v4l2_subdev *sd)
+{
+	struct i2c_client *client = v4l2_get_subdevdata(sd);
+	int ret;
+
+	/* Set APB peripherals start address */
+	ret = s5k4ecgx_i2c_write(client, AHB_MSB_ADDR_PTR, GEN_REG_OFFSH);
+	if (ret < 0)
+		return ret;
+	/*
+	 * FIXME: This is copied from s5k6aa, because of no information
+	 * in s5k4ecgx's datasheet.
+	 * sw_reset is activated to put device into idle status
+	 */
+	ret = s5k4ecgx_i2c_write(client, 0x0010, 0x0001);
+	if (ret < 0)
+		return ret;
+
+	ret = s5k4ecgx_i2c_write(client, 0x1030, 0x0000);
+	if (ret < 0)
+		return ret;
+	/* Halt ARM CPU */
+	return s5k4ecgx_i2c_write(client, 0x0014, 0x0001);
+}
+
+#define FW_CRC_SIZE	4
+/* Register address, value are 4, 2 bytes */
+#define FW_RECORD_SIZE	6
+/*
+ * The firmware has following format:
+ * < total number of records (4 bytes + 2 bytes padding) N >,
+ * < record 0 >, ..., < record N - 1 >, < CRC32-CCITT (4-bytes) >,
+ * where "record" is a 4-byte register address followed by 2-byte
+ * register value (little endian).
+ * The firmware generator can be found in following git repository:
+ * git://git.linaro.org/people/sangwook/fimc-v4l2-app.git
+ */
+static int s5k4ecgx_load_firmware(struct v4l2_subdev *sd)
+{
+	struct i2c_client *client = v4l2_get_subdevdata(sd);
+	const struct firmware *fw;
+	const u8 *ptr;
+	int err, i, regs_num;
+	u32 addr, crc, crc_file, addr_inc = 0;
+	u16 val;
+
+	err = request_firmware(&fw, S5K4ECGX_FIRMWARE, sd->v4l2_dev->dev);
+	if (err) {
+		v4l2_err(sd, "Failed to read firmware %s\n", S5K4ECGX_FIRMWARE);
+		return err;
+	}
+	regs_num = le32_to_cpu(get_unaligned_le32(fw->data));
+
+	v4l2_dbg(3, debug, sd, "FW: %s size %d register sets %d\n",
+		 S5K4ECGX_FIRMWARE, fw->size, regs_num);
+
+	regs_num++; /* Add header */
+	if (fw->size != regs_num * FW_RECORD_SIZE + FW_CRC_SIZE) {
+		err = -EINVAL;
+		goto fw_out;
+	}
+	crc_file = le32_to_cpu(get_unaligned_le32(fw->data +
+						  regs_num * FW_RECORD_SIZE));
+	crc = crc32_le(~0, fw->data, regs_num * FW_RECORD_SIZE);
+	if (crc != crc_file) {
+		v4l2_err(sd, "FW: invalid crc (%#x:%#x)\n", crc, crc_file);
+		err = -EINVAL;
+		goto fw_out;
+	}
+	ptr = fw->data + FW_RECORD_SIZE;
+	for (i = 1; i < regs_num; i++) {
+		addr = le32_to_cpu(get_unaligned_le32(ptr));
+		ptr += sizeof(u32);
+		val = le16_to_cpu(get_unaligned_le16(ptr));
+		ptr += sizeof(u16);
+		if (addr - addr_inc != 2)
+			err = s5k4ecgx_write(client, addr, val);
+		else
+			err = s5k4ecgx_i2c_write(client, REG_CMDBUF0_ADDR, val);
+		if (err)
+			break;
+		addr_inc = addr;
+	}
+fw_out:
+	release_firmware(fw);
+	return err;
+}
+
+/* Set preview and capture input window */
+static int s5k4ecgx_set_input_window(struct i2c_client *c,
+				     const struct v4l2_rect *r)
+{
+	int ret;
+
+	ret = s5k4ecgx_write(c, REG_G_PREV_IN_WIDTH, r->width);
+	if (!ret)
+		ret = s5k4ecgx_write(c, REG_G_PREV_IN_HEIGHT, r->height);
+	if (!ret)
+		ret = s5k4ecgx_write(c, REG_G_PREV_IN_XOFFS, r->left);
+	if (!ret)
+		ret = s5k4ecgx_write(c, REG_G_PREV_IN_YOFFS, r->top);
+	if (!ret)
+		ret = s5k4ecgx_write(c, REG_G_CAP_IN_WIDTH, r->width);
+	if (!ret)
+		ret = s5k4ecgx_write(c, REG_G_CAP_IN_HEIGHT, r->height);
+	if (!ret)
+		ret = s5k4ecgx_write(c, REG_G_CAP_IN_XOFFS, r->left);
+	if (!ret)
+		ret = s5k4ecgx_write(c, REG_G_CAP_IN_YOFFS, r->top);
+
+	return ret;
+}
+
+/* Set preview and capture zoom input window */
+static int s5k4ecgx_set_zoom_window(struct i2c_client *c,
+				    const struct v4l2_rect *r)
+{
+	int ret;
+
+	ret = s5k4ecgx_write(c, REG_G_PREVZOOM_IN_WIDTH, r->width);
+	if (!ret)
+		ret = s5k4ecgx_write(c, REG_G_PREVZOOM_IN_HEIGHT, r->height);
+	if (!ret)
+		ret = s5k4ecgx_write(c, REG_G_PREVZOOM_IN_XOFFS, r->left);
+	if (!ret)
+		ret = s5k4ecgx_write(c, REG_G_PREVZOOM_IN_YOFFS, r->top);
+	if (!ret)
+		ret = s5k4ecgx_write(c, REG_G_CAPZOOM_IN_WIDTH, r->width);
+	if (!ret)
+		ret = s5k4ecgx_write(c, REG_G_CAPZOOM_IN_HEIGHT, r->height);
+	if (!ret)
+		ret = s5k4ecgx_write(c, REG_G_CAPZOOM_IN_XOFFS, r->left);
+	if (!ret)
+		ret = s5k4ecgx_write(c, REG_G_CAPZOOM_IN_YOFFS, r->top);
+
+	return ret;
+}
+
+static int s5k4ecgx_set_output_framefmt(struct s5k4ecgx *priv)
+{
+	struct i2c_client *client = v4l2_get_subdevdata(&priv->sd);
+	int ret;
+
+	ret = s5k4ecgx_write(client, REG_P_OUT_WIDTH(0),
+			     priv->curr_frmsize->size.width);
+	if (!ret)
+		ret = s5k4ecgx_write(client, REG_P_OUT_HEIGHT(0),
+				     priv->curr_frmsize->size.height);
+	if (!ret)
+		ret = s5k4ecgx_write(client, REG_P_FMT(0),
+				     priv->curr_pixfmt->reg_p_format);
+	return ret;
+}
+
+static int s5k4ecgx_init_sensor(struct v4l2_subdev *sd)
+{
+	int ret;
+
+	ret = s5k4ecgx_set_ahb_address(sd);
+
+	/* The delay is from manufacturer's settings */
+	msleep(100);
+
+	if (!ret)
+		ret = s5k4ecgx_load_firmware(sd);
+	if (ret)
+		v4l2_err(sd, "Failed to write initial settings\n");
+
+	return ret;
+}
+
+static int s5k4ecgx_gpio_set_value(struct s5k4ecgx *priv, int id, u32 val)
+{
+	if (!gpio_is_valid(priv->gpio[id].gpio))
+		return 0;
+	gpio_set_value(priv->gpio[id].gpio, val);
+
+	return 1;
+}
+
+static int __s5k4ecgx_power_on(struct s5k4ecgx *priv)
+{
+	int ret;
+
+	ret = regulator_bulk_enable(S5K4ECGX_NUM_SUPPLIES, priv->supplies);
+	if (ret)
+		return ret;
+	usleep_range(30, 50);
+
+	/* The polarity of STBY is controlled by TSP */
+	if (s5k4ecgx_gpio_set_value(priv, STBY, priv->gpio[STBY].level))
+		usleep_range(30, 50);
+
+	if (s5k4ecgx_gpio_set_value(priv, RST, priv->gpio[RST].level))
+		usleep_range(30, 50);
+
+	return 0;
+}
+
+static int __s5k4ecgx_power_off(struct s5k4ecgx *priv)
+{
+	if (s5k4ecgx_gpio_set_value(priv, RST, !priv->gpio[RST].level))
+		usleep_range(30, 50);
+
+	if (s5k4ecgx_gpio_set_value(priv, STBY, !priv->gpio[STBY].level))
+		usleep_range(30, 50);
+
+	priv->streaming = 0;
+
+	return regulator_bulk_disable(S5K4ECGX_NUM_SUPPLIES, priv->supplies);
+}
+
+/* Find nearest matching image pixel size. */
+static int s5k4ecgx_try_frame_size(struct v4l2_mbus_framefmt *mf,
+				  const struct s5k4ecgx_frmsize **size)
+{
+	unsigned int min_err = ~0;
+	int i = ARRAY_SIZE(s5k4ecgx_prev_sizes);
+	const struct s5k4ecgx_frmsize *fsize = &s5k4ecgx_prev_sizes[0],
+		*match = NULL;
+
+	while (i--) {
+		int err = abs(fsize->size.width - mf->width)
+				+ abs(fsize->size.height - mf->height);
+		if (err < min_err) {
+			min_err = err;
+			match = fsize;
+		}
+		fsize++;
+	}
+	if (match) {
+		mf->width  = match->size.width;
+		mf->height = match->size.height;
+		if (size)
+			*size = match;
+		return 0;
+	}
+
+	return -EINVAL;
+}
+
+static int s5k4ecgx_enum_mbus_code(struct v4l2_subdev *sd,
+				   struct v4l2_subdev_fh *fh,
+				   struct v4l2_subdev_mbus_code_enum *code)
+{
+	if (code->index >= ARRAY_SIZE(s5k4ecgx_formats))
+		return -EINVAL;
+	code->code = s5k4ecgx_formats[code->index].code;
+
+	return 0;
+}
+
+static int s5k4ecgx_get_fmt(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh,
+			   struct v4l2_subdev_format *fmt)
+{
+	struct s5k4ecgx *priv = to_s5k4ecgx(sd);
+	struct v4l2_mbus_framefmt *mf;
+
+	if (fmt->which == V4L2_SUBDEV_FORMAT_TRY) {
+		if (fh) {
+			mf = v4l2_subdev_get_try_format(fh, 0);
+			fmt->format = *mf;
+		}
+		return 0;
+	}
+
+	mf = &fmt->format;
+
+	mutex_lock(&priv->lock);
+	mf->width = priv->curr_frmsize->size.width;
+	mf->height = priv->curr_frmsize->size.height;
+	mf->code = priv->curr_pixfmt->code;
+	mf->colorspace = priv->curr_pixfmt->colorspace;
+	mf->field = V4L2_FIELD_NONE;
+	mutex_unlock(&priv->lock);
+
+	return 0;
+}
+
+static const struct s5k4ecgx_pixfmt *s5k4ecgx_try_fmt(struct v4l2_subdev *sd,
+					    struct v4l2_mbus_framefmt *mf)
+{
+	int i = ARRAY_SIZE(s5k4ecgx_formats);
+
+	while (--i)
+		if (mf->code == s5k4ecgx_formats[i].code)
+			break;
+	mf->code = s5k4ecgx_formats[i].code;
+
+	return &s5k4ecgx_formats[i];
+}
+
+static int s5k4ecgx_set_fmt(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh,
+			    struct v4l2_subdev_format *fmt)
+{
+	struct s5k4ecgx *priv = to_s5k4ecgx(sd);
+	const struct s5k4ecgx_frmsize *fsize = NULL;
+	const struct s5k4ecgx_pixfmt *pf;
+	struct v4l2_mbus_framefmt *mf;
+	int ret = 0;
+
+	pf = s5k4ecgx_try_fmt(sd, &fmt->format);
+	s5k4ecgx_try_frame_size(&fmt->format, &fsize);
+	fmt->format.colorspace = V4L2_COLORSPACE_JPEG;
+
+	if (fmt->which == V4L2_SUBDEV_FORMAT_TRY) {
+		if (fh) {
+			mf = v4l2_subdev_get_try_format(fh, 0);
+			*mf = fmt->format;
+		}
+		return 0;
+	}
+
+	mutex_lock(&priv->lock);
+	if (!priv->streaming) {
+		priv->curr_frmsize = fsize;
+		priv->curr_pixfmt = pf;
+		priv->set_params = 1;
+	} else {
+		ret = -EBUSY;
+	}
+	mutex_unlock(&priv->lock);
+
+	return ret;
+}
+
+static const struct v4l2_subdev_pad_ops s5k4ecgx_pad_ops = {
+	.enum_mbus_code	= s5k4ecgx_enum_mbus_code,
+	.get_fmt	= s5k4ecgx_get_fmt,
+	.set_fmt	= s5k4ecgx_set_fmt,
+};
+
+/*
+ * V4L2 subdev controls
+ */
+static int s5k4ecgx_s_ctrl(struct v4l2_ctrl *ctrl)
+{
+	struct v4l2_subdev *sd = &container_of(ctrl->handler, struct s5k4ecgx,
+						handler)->sd;
+	struct i2c_client *client = v4l2_get_subdevdata(sd);
+	struct s5k4ecgx *priv = to_s5k4ecgx(sd);
+	unsigned int i;
+	int err = 0;
+
+	v4l2_dbg(1, debug, sd, "ctrl: 0x%x, value: %d\n", ctrl->id, ctrl->val);
+
+	mutex_lock(&priv->lock);
+	switch (ctrl->id) {
+	case V4L2_CID_CONTRAST:
+		err = s5k4ecgx_write(client, REG_USER_CONTRAST, ctrl->val);
+		break;
+
+	case V4L2_CID_SATURATION:
+		err = s5k4ecgx_write(client, REG_USER_SATURATION, ctrl->val);
+		break;
+
+	case V4L2_CID_SHARPNESS:
+		/* TODO: Revisit, is this setting for all presets ? */
+		for (i = 0; i < 4 && !err; i++)
+			err = s5k4ecgx_write(client, REG_USER_SHARPNESS(i),
+					     ctrl->val * SHARPNESS_DIV);
+		break;
+
+	case V4L2_CID_BRIGHTNESS:
+		err = s5k4ecgx_write(client, REG_USER_BRIGHTNESS, ctrl->val);
+		break;
+	}
+	mutex_unlock(&priv->lock);
+	if (err < 0)
+		v4l2_err(sd, "Failed to write s_ctrl err %d\n", err);
+
+	return err;
+}
+
+static const struct v4l2_ctrl_ops s5k4ecgx_ctrl_ops = {
+	.s_ctrl = s5k4ecgx_s_ctrl,
+};
+
+/*
+ * Reading s5k4ecgx version information
+ */
+static int s5k4ecgx_registered(struct v4l2_subdev *sd)
+{
+	int ret;
+	struct s5k4ecgx *priv = to_s5k4ecgx(sd);
+
+	mutex_lock(&priv->lock);
+	ret = __s5k4ecgx_power_on(priv);
+	if (!ret) {
+		ret = s5k4ecgx_read_fw_ver(sd);
+		__s5k4ecgx_power_off(priv);
+	}
+	mutex_unlock(&priv->lock);
+
+	return ret;
+}
+
+/*
+ * V4L2 subdev internal operations
+ */
+static int s5k4ecgx_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
+{
+	struct v4l2_mbus_framefmt *mf = v4l2_subdev_get_try_format(fh, 0);
+
+	mf->width = s5k4ecgx_prev_sizes[0].size.width;
+	mf->height = s5k4ecgx_prev_sizes[0].size.height;
+	mf->code = s5k4ecgx_formats[0].code;
+	mf->colorspace = V4L2_COLORSPACE_JPEG;
+	mf->field = V4L2_FIELD_NONE;
+
+	return 0;
+}
+
+static const struct v4l2_subdev_internal_ops s5k4ecgx_subdev_internal_ops = {
+	.registered = s5k4ecgx_registered,
+	.open = s5k4ecgx_open,
+};
+
+static int s5k4ecgx_s_power(struct v4l2_subdev *sd, int on)
+{
+	struct s5k4ecgx *priv = to_s5k4ecgx(sd);
+	int ret;
+
+	v4l2_dbg(1, debug, sd, "Switching %s\n", on ? "on" : "off");
+
+	if (on) {
+		ret = __s5k4ecgx_power_on(priv);
+		if (ret < 0)
+			return ret;
+		/* Time to stabilize sensor */
+		msleep(100);
+		ret = s5k4ecgx_init_sensor(sd);
+		if (ret < 0)
+			__s5k4ecgx_power_off(priv);
+		else
+			priv->set_params = 1;
+	} else {
+		ret = __s5k4ecgx_power_off(priv);
+	}
+
+	return ret;
+}
+
+static int s5k4ecgx_log_status(struct v4l2_subdev *sd)
+{
+	v4l2_ctrl_handler_log_status(sd->ctrl_handler, sd->name);
+
+	return 0;
+}
+
+static const struct v4l2_subdev_core_ops s5k4ecgx_core_ops = {
+	.s_power	= s5k4ecgx_s_power,
+	.log_status	= s5k4ecgx_log_status,
+};
+
+static int __s5k4ecgx_s_params(struct s5k4ecgx *priv)
+{
+	struct i2c_client *client = v4l2_get_subdevdata(&priv->sd);
+	const struct v4l2_rect *crop_rect = &priv->curr_frmsize->input_window;
+	int ret;
+
+	ret = s5k4ecgx_set_input_window(client, crop_rect);
+	if (!ret)
+		ret = s5k4ecgx_set_zoom_window(client, crop_rect);
+	if (!ret)
+		ret = s5k4ecgx_write(client, REG_G_INPUTS_CHANGE_REQ, 1);
+	if (!ret)
+		ret = s5k4ecgx_write(client, 0x70000a1e, 0x28);
+	if (!ret)
+		ret = s5k4ecgx_write(client, 0x70000ad4, 0x3c);
+	if (!ret)
+		ret = s5k4ecgx_set_output_framefmt(priv);
+	if (!ret)
+		ret = s5k4ecgx_write(client, REG_P_PVI_MASK(0), 0x52);
+	if (!ret)
+		ret = s5k4ecgx_write(client, REG_P_FR_TIME_TYPE(0),
+				     FR_TIME_DYNAMIC);
+	if (!ret)
+		ret = s5k4ecgx_write(client, REG_P_FR_TIME_Q_TYPE(0),
+				     FR_TIME_Q_BEST_FRRATE);
+	if (!ret)
+		ret = s5k4ecgx_write(client,  REG_P_MIN_FR_TIME(0),
+				     US_TO_FR_TIME(33300));
+	if (!ret)
+		ret = s5k4ecgx_write(client, REG_P_MAX_FR_TIME(0),
+				     US_TO_FR_TIME(66600));
+	if (!ret)
+		ret = s5k4ecgx_write(client, REG_P_PREV_MIRROR(0), 0);
+	if (!ret)
+		ret = s5k4ecgx_write(client, REG_P_CAP_MIRROR(0), 0);
+	if (!ret)
+		ret = s5k4ecgx_write(client, REG_G_ACTIVE_PREV_CFG, 0);
+	if (!ret)
+		ret = s5k4ecgx_write(client, REG_G_PREV_OPEN_AFTER_CH, 1);
+	if (!ret)
+		ret = s5k4ecgx_write(client, REG_G_NEW_CFG_SYNC, 1);
+	if (!ret)
+		ret = s5k4ecgx_write(client, REG_G_PREV_CFG_CHG, 1);
+
+	return ret;
+}
+
+static int __s5k4ecgx_s_stream(struct s5k4ecgx *priv, int on)
+{
+	struct i2c_client *client = v4l2_get_subdevdata(&priv->sd);
+	int ret;
+
+	if (on && priv->set_params) {
+		ret = __s5k4ecgx_s_params(priv);
+		if (ret < 0)
+			return ret;
+		priv->set_params = 0;
+	}
+	/*
+	 * This enables/disables preview stream only. Capture requests
+	 * are not supported yet.
+	 */
+	ret = s5k4ecgx_write(client, REG_G_ENABLE_PREV, on);
+	if (ret < 0)
+		return ret;
+	return s5k4ecgx_write(client, REG_G_ENABLE_PREV_CHG, 1);
+}
+
+static int s5k4ecgx_s_stream(struct v4l2_subdev *sd, int on)
+{
+	struct s5k4ecgx *priv = to_s5k4ecgx(sd);
+	int ret = 0;
+
+	v4l2_dbg(1, debug, sd, "Turn streaming %s\n", on ? "on" : "off");
+
+	mutex_lock(&priv->lock);
+
+	if (priv->streaming == !on) {
+		ret = __s5k4ecgx_s_stream(priv, on);
+		if (!ret)
+			priv->streaming = on & 1;
+	}
+
+	mutex_unlock(&priv->lock);
+	return ret;
+}
+
+static const struct v4l2_subdev_video_ops s5k4ecgx_video_ops = {
+	.s_stream = s5k4ecgx_s_stream,
+};
+
+static const struct v4l2_subdev_ops s5k4ecgx_ops = {
+	.core = &s5k4ecgx_core_ops,
+	.pad = &s5k4ecgx_pad_ops,
+	.video = &s5k4ecgx_video_ops,
+};
+
+/*
+ * GPIO setup
+ */
+static int s5k4ecgx_config_gpio(int nr, int val, const char *name)
+{
+	unsigned long flags = val ? GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW;
+	int ret;
+
+	if (!gpio_is_valid(nr))
+		return 0;
+	ret = gpio_request_one(nr, flags, name);
+	if (!ret)
+		gpio_export(nr, 0);
+
+	return ret;
+}
+
+static void s5k4ecgx_free_gpios(struct s5k4ecgx *priv)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(priv->gpio); i++) {
+		if (!gpio_is_valid(priv->gpio[i].gpio))
+			continue;
+		gpio_free(priv->gpio[i].gpio);
+		priv->gpio[i].gpio = -EINVAL;
+	}
+}
+
+static int s5k4ecgx_config_gpios(struct s5k4ecgx *priv,
+				  const struct s5k4ecgx_platform_data *pdata)
+{
+	const struct s5k4ecgx_gpio *gpio = &pdata->gpio_stby;
+	int ret;
+
+	priv->gpio[STBY].gpio = -EINVAL;
+	priv->gpio[RST].gpio  = -EINVAL;
+
+	ret = s5k4ecgx_config_gpio(gpio->gpio, gpio->level, "S5K4ECGX_STBY");
+
+	if (ret) {
+		s5k4ecgx_free_gpios(priv);
+		return ret;
+	}
+	priv->gpio[STBY] = *gpio;
+	if (gpio_is_valid(gpio->gpio))
+		gpio_set_value(gpio->gpio, 0);
+
+	gpio = &pdata->gpio_reset;
+
+	ret = s5k4ecgx_config_gpio(gpio->gpio, gpio->level, "S5K4ECGX_RST");
+	if (ret) {
+		s5k4ecgx_free_gpios(priv);
+		return ret;
+	}
+	priv->gpio[RST] = *gpio;
+	if (gpio_is_valid(gpio->gpio))
+		gpio_set_value(gpio->gpio, 0);
+
+	return 0;
+}
+
+static int s5k4ecgx_init_v4l2_ctrls(struct s5k4ecgx *priv)
+{
+	const struct v4l2_ctrl_ops *ops = &s5k4ecgx_ctrl_ops;
+	struct v4l2_ctrl_handler *hdl = &priv->handler;
+	int ret;
+
+	ret = v4l2_ctrl_handler_init(hdl, 4);
+	if (ret)
+		return ret;
+
+	v4l2_ctrl_new_std(hdl, ops, V4L2_CID_BRIGHTNESS, -208, 127, 1, 0);
+	v4l2_ctrl_new_std(hdl, ops, V4L2_CID_CONTRAST, -127, 127, 1, 0);
+	v4l2_ctrl_new_std(hdl, ops, V4L2_CID_SATURATION, -127, 127, 1, 0);
+
+	/* Sharpness default is 24612, and then (24612/SHARPNESS_DIV) = 2 */
+	v4l2_ctrl_new_std(hdl, ops, V4L2_CID_SHARPNESS, -32704/SHARPNESS_DIV,
+			  24612/SHARPNESS_DIV, 1, 2);
+	if (hdl->error) {
+		ret = hdl->error;
+		v4l2_ctrl_handler_free(hdl);
+		return ret;
+	}
+	priv->sd.ctrl_handler = hdl;
+
+	return 0;
+};
+
+static int s5k4ecgx_probe(struct i2c_client *client,
+			  const struct i2c_device_id *id)
+{
+	struct s5k4ecgx_platform_data *pdata = client->dev.platform_data;
+	struct v4l2_subdev *sd;
+	struct s5k4ecgx *priv;
+	int ret, i;
+
+	if (pdata == NULL) {
+		dev_err(&client->dev, "platform data is missing!\n");
+		return -EINVAL;
+	}
+
+	priv = devm_kzalloc(&client->dev, sizeof(struct s5k4ecgx), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	mutex_init(&priv->lock);
+	priv->streaming = 0;
+
+	sd = &priv->sd;
+	/* Registering subdev */
+	v4l2_i2c_subdev_init(sd, client, &s5k4ecgx_ops);
+	strlcpy(sd->name, S5K4ECGX_DRIVER_NAME, sizeof(sd->name));
+
+	sd->internal_ops = &s5k4ecgx_subdev_internal_ops;
+	/* Support v4l2 sub-device user space API */
+	sd->flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
+
+	priv->pad.flags = MEDIA_PAD_FL_SOURCE;
+	sd->entity.type = MEDIA_ENT_T_V4L2_SUBDEV_SENSOR;
+	ret = media_entity_init(&sd->entity, 1, &priv->pad, 0);
+	if (ret)
+		return ret;
+
+	ret = s5k4ecgx_config_gpios(priv, pdata);
+	if (ret) {
+		dev_err(&client->dev, "Failed to set gpios\n");
+		goto out_err1;
+	}
+	for (i = 0; i < S5K4ECGX_NUM_SUPPLIES; i++)
+		priv->supplies[i].supply = s5k4ecgx_supply_names[i];
+
+	ret = devm_regulator_bulk_get(&client->dev, S5K4ECGX_NUM_SUPPLIES,
+				 priv->supplies);
+	if (ret) {
+		dev_err(&client->dev, "Failed to get regulators\n");
+		goto out_err2;
+	}
+	ret = s5k4ecgx_init_v4l2_ctrls(priv);
+	if (ret)
+		goto out_err2;
+
+	priv->curr_pixfmt = &s5k4ecgx_formats[0];
+	priv->curr_frmsize = &s5k4ecgx_prev_sizes[0];
+
+	return 0;
+
+out_err2:
+	s5k4ecgx_free_gpios(priv);
+out_err1:
+	media_entity_cleanup(&priv->sd.entity);
+
+	return ret;
+}
+
+static int s5k4ecgx_remove(struct i2c_client *client)
+{
+	struct v4l2_subdev *sd = i2c_get_clientdata(client);
+	struct s5k4ecgx *priv = to_s5k4ecgx(sd);
+
+	mutex_destroy(&priv->lock);
+	s5k4ecgx_free_gpios(priv);
+	v4l2_device_unregister_subdev(sd);
+	v4l2_ctrl_handler_free(&priv->handler);
+	media_entity_cleanup(&sd->entity);
+
+	return 0;
+}
+
+static const struct i2c_device_id s5k4ecgx_id[] = {
+	{ S5K4ECGX_DRIVER_NAME, 0 },
+	{}
+};
+MODULE_DEVICE_TABLE(i2c, s5k4ecgx_id);
+
+static struct i2c_driver v4l2_i2c_driver = {
+	.driver = {
+		.owner	= THIS_MODULE,
+		.name = S5K4ECGX_DRIVER_NAME,
+	},
+	.probe = s5k4ecgx_probe,
+	.remove = s5k4ecgx_remove,
+	.id_table = s5k4ecgx_id,
+};
+
+module_i2c_driver(v4l2_i2c_driver);
+
+MODULE_DESCRIPTION("Samsung S5K4ECGX 5MP SOC camera");
+MODULE_AUTHOR("Sangwook Lee <sangwook.lee@linaro.org>");
+MODULE_AUTHOR("Seok-Young Jang <quartz.jang@samsung.com>");
+MODULE_LICENSE("GPL");
+MODULE_FIRMWARE(S5K4ECGX_FIRMWARE);