[PATCH v3] hi556: Add support for Hi-556 sensor

[Shawnx Tu <shawnx.tu@intel.com>]

From: Shawn Tu <shawnx.tu@intel.com>

Add a V4L2 sub-device driver for Hynix Hi-556 image sensor.
This is a camera sensor using the I2C bus for control and the
CSI-2 bus for data.

This driver supports following features:
- manual exposure and analog/digital gain control support
- vblank/hblank control support
- test pattern support
- media controller support
- runtime PM support
- support following resolutions:
  + 2592x1944 at 30FPS
  + 1296x972  at 30FPS

Signed-off-by: Shawn Tu <shawnx.tu@intel.com>
---
 MAINTAINERS                |    7 +
 drivers/media/i2c/Kconfig  |   13 +
 drivers/media/i2c/Makefile |    1 +
 drivers/media/i2c/hi556.c  | 1194 ++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 1215 insertions(+)
 create mode 100644 drivers/media/i2c/hi556.c

diff --git a/MAINTAINERS b/MAINTAINERS
index c6c34d0..eacf0ad 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -7546,6 +7546,13 @@ L:	linux-kernel@vger.kernel.org
 S:	Maintained
 F:	arch/x86/kernel/cpu/hygon.c
 
+HYNIX HI556 SENSOR DRIVER
+M:	Shawn Tu <shawnx.tu@intel.com>
+L:	linux-media@vger.kernel.org
+T:	git git://linuxtv.org/media_tree.git
+S:	Maintained
+F:	drivers/media/i2c/hi556.c
+
 Hyper-V CORE AND DRIVERS
 M:	"K. Y. Srinivasan" <kys@microsoft.com>
 M:	Haiyang Zhang <haiyangz@microsoft.com>
diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
index 7eee181..eab4b78 100644
--- a/drivers/media/i2c/Kconfig
+++ b/drivers/media/i2c/Kconfig
@@ -566,6 +566,19 @@ config VIDEO_APTINA_PLL
 config VIDEO_SMIAPP_PLL
 	tristate
 
+config VIDEO_HI556
+	tristate "Hynix Hi-556 sensor support"
+	depends on I2C && VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API
+	depends on MEDIA_CAMERA_SUPPORT
+	depends on MEDIA_CONTROLLER
+	select V4L2_FWNODE
+	help
+	  This is a Video4Linux2 sensor driver for the Hynix
+	  Hi-556 camera.
+
+	To compile this driver as a module, choose M here: the
+	module will be called hi556.
+
 config VIDEO_IMX214
 	tristate "Sony IMX214 sensor support"
 	depends on GPIOLIB && I2C && VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API
diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile
index beb170b..b492c4b 100644
--- a/drivers/media/i2c/Makefile
+++ b/drivers/media/i2c/Makefile
@@ -109,6 +109,7 @@ obj-$(CONFIG_VIDEO_I2C)		+= video-i2c.o
 obj-$(CONFIG_VIDEO_ML86V7667)	+= ml86v7667.o
 obj-$(CONFIG_VIDEO_OV2659)	+= ov2659.o
 obj-$(CONFIG_VIDEO_TC358743)	+= tc358743.o
+obj-$(CONFIG_VIDEO_HI556)	+= hi556.o
 obj-$(CONFIG_VIDEO_IMX214)	+= imx214.o
 obj-$(CONFIG_VIDEO_IMX258)	+= imx258.o
 obj-$(CONFIG_VIDEO_IMX274)	+= imx274.o
diff --git a/drivers/media/i2c/hi556.c b/drivers/media/i2c/hi556.c
new file mode 100644
index 0000000..cdee2bc
--- /dev/null
+++ b/drivers/media/i2c/hi556.c
@@ -0,0 +1,1194 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2019 Intel Corporation.
+
+#include <asm/unaligned.h>
+#include <linux/acpi.h>
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/pm_runtime.h>
+#include <media/v4l2-ctrls.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-fwnode.h>
+
+#define HI556_REG_VALUE_08BIT		1
+#define HI556_REG_VALUE_16BIT		2
+#define HI556_REG_VALUE_24BIT		3
+
+#define HI556_LINK_FREQ_437MHZ		437000000ULL
+#define HI556_MCLK			19200000
+#define HI556_DATA_LANES		2
+#define HI556_RGB_DEPTH			10
+
+#define HI556_REG_CHIP_ID		0x0f16
+#define HI556_CHIP_ID			0x0556
+
+#define HI556_REG_MODE_SELECT		0x0a00
+#define HI556_MODE_STANDBY		0x0000
+#define HI556_MODE_STREAMING		0x0100
+
+/* vertical-timings from sensor */
+#define HI556_REG_FLL			0x0006
+#define HI556_FLL_30FPS			0x0814
+#define HI556_FLL_30FPS_MIN		0x0814
+#define HI556_FLL_MAX			0x7fff
+
+/* horizontal-timings from sensor */
+#define HI556_REG_LLP			0x0008
+
+/* Exposure controls from sensor */
+#define HI556_REG_EXPOSURE		0x0074
+#define HI556_EXPOSURE_MIN		6
+#define HI556_EXPOSURE_MAX_MARGIN	2
+#define HI556_EXPOSURE_STEP		1
+
+/* Analog gain controls from sensor */
+#define HI556_REG_ANALOG_GAIN		0x0077
+#define HI556_ANAL_GAIN_MIN		0
+#define HI556_ANAL_GAIN_MAX		240
+#define HI556_ANAL_GAIN_STEP		1
+
+/* Digital gain controls from sensor */
+#define HI556_REG_MWB_GR_GAIN		0x0078
+#define HI556_REG_MWB_GB_GAIN		0x007a
+#define HI556_REG_MWB_R_GAIN		0x007c
+#define HI556_REG_MWB_B_GAIN		0x007e
+#define HI556_DGTL_GAIN_MIN		0
+#define HI556_DGTL_GAIN_MAX		2048
+#define HI556_DGTL_GAIN_STEP		1
+#define HI556_DGTL_GAIN_DEFAULT		256
+
+/* Test Pattern Control */
+#define HI556_REG_ISP			0X0a05
+#define HI556_REG_ISP_TPG_EN		0x01
+#define HI556_REG_TEST_PATTERN		0x0201
+
+enum {
+	HI556_LINK_FREQ_437MHZ_INDEX,
+};
+
+struct hi556_reg {
+	u16 address;
+	u16 val;
+};
+
+struct hi556_reg_list {
+	u32 num_of_regs;
+	const struct hi556_reg *regs;
+};
+
+struct hi556_link_freq_config {
+	const struct hi556_reg_list reg_list;
+};
+
+struct hi556_mode {
+	/* Frame width in pixels */
+	u32 width;
+
+	/* Frame height in pixels */
+	u32 height;
+
+	/* Horizontal timining size */
+	u32 llp;
+
+	/* Default vertical timining size */
+	u32 fll_def;
+
+	/* Min vertical timining size */
+	u32 fll_min;
+
+	/* Link frequency needed for this resolution */
+	u32 link_freq_index;
+
+	/* Sensor register settings for this resolution */
+	const struct hi556_reg_list reg_list;
+};
+
+#define to_hi556(_sd) container_of(_sd, struct hi556, sd)
+
+//SENSOR_INITIALIZATION
+static const struct hi556_reg mipi_data_rate_874mbps[] = {
+	{0x0e00, 0x0102},
+	{0x0e02, 0x0102},
+	{0x0e0c, 0x0100},
+	{0x2000, 0x7400},
+	{0x2002, 0x001c},
+	{0x2004, 0x0242},
+	{0x2006, 0x0942},
+	{0x2008, 0x7007},
+	{0x200a, 0x0fd9},
+	{0x200c, 0x0259},
+	{0x200e, 0x7008},
+	{0x2010, 0x160e},
+	{0x2012, 0x0047},
+	{0x2014, 0x2118},
+	{0x2016, 0x0041},
+	{0x2018, 0x00d8},
+	{0x201a, 0x0145},
+	{0x201c, 0x0006},
+	{0x201e, 0x0181},
+	{0x2020, 0x13cc},
+	{0x2022, 0x2057},
+	{0x2024, 0x7001},
+	{0x2026, 0x0fca},
+	{0x2028, 0x00cb},
+	{0x202a, 0x009f},
+	{0x202c, 0x7002},
+	{0x202e, 0x13cc},
+	{0x2030, 0x019b},
+	{0x2032, 0x014d},
+	{0x2034, 0x2987},
+	{0x2036, 0x2766},
+	{0x2038, 0x0020},
+	{0x203a, 0x2060},
+	{0x203c, 0x0e5d},
+	{0x203e, 0x181d},
+	{0x2040, 0x2066},
+	{0x2042, 0x20c4},
+	{0x2044, 0x5000},
+	{0x2046, 0x0005},
+	{0x2048, 0x0000},
+	{0x204a, 0x01db},
+	{0x204c, 0x025a},
+	{0x204e, 0x00c0},
+	{0x2050, 0x0005},
+	{0x2052, 0x0006},
+	{0x2054, 0x0ad9},
+	{0x2056, 0x0259},
+	{0x2058, 0x0618},
+	{0x205a, 0x0258},
+	{0x205c, 0x2266},
+	{0x205e, 0x20c8},
+	{0x2060, 0x2060},
+	{0x2062, 0x707b},
+	{0x2064, 0x0fdd},
+	{0x2066, 0x81b8},
+	{0x2068, 0x5040},
+	{0x206a, 0x0020},
+	{0x206c, 0x5060},
+	{0x206e, 0x3143},
+	{0x2070, 0x5081},
+	{0x2072, 0x025c},
+	{0x2074, 0x7800},
+	{0x2076, 0x7400},
+	{0x2078, 0x001c},
+	{0x207a, 0x0242},
+	{0x207c, 0x0942},
+	{0x207e, 0x0bd9},
+	{0x2080, 0x0259},
+	{0x2082, 0x7008},
+	{0x2084, 0x160e},
+	{0x2086, 0x0047},
+	{0x2088, 0x2118},
+	{0x208a, 0x0041},
+	{0x208c, 0x00d8},
+	{0x208e, 0x0145},
+	{0x2090, 0x0006},
+	{0x2092, 0x0181},
+	{0x2094, 0x13cc},
+	{0x2096, 0x2057},
+	{0x2098, 0x7001},
+	{0x209a, 0x0fca},
+	{0x209c, 0x00cb},
+	{0x209e, 0x009f},
+	{0x20a0, 0x7002},
+	{0x20a2, 0x13cc},
+	{0x20a4, 0x019b},
+	{0x20a6, 0x014d},
+	{0x20a8, 0x2987},
+	{0x20aa, 0x2766},
+	{0x20ac, 0x0020},
+	{0x20ae, 0x2060},
+	{0x20b0, 0x0e5d},
+	{0x20b2, 0x181d},
+	{0x20b4, 0x2066},
+	{0x20b6, 0x20c4},
+	{0x20b8, 0x50a0},
+	{0x20ba, 0x0005},
+	{0x20bc, 0x0000},
+	{0x20be, 0x01db},
+	{0x20c0, 0x025a},
+	{0x20c2, 0x00c0},
+	{0x20c4, 0x0005},
+	{0x20c6, 0x0006},
+	{0x20c8, 0x0ad9},
+	{0x20ca, 0x0259},
+	{0x20cc, 0x0618},
+	{0x20ce, 0x0258},
+	{0x20d0, 0x2266},
+	{0x20d2, 0x20c8},
+	{0x20d4, 0x2060},
+	{0x20d6, 0x707b},
+	{0x20d8, 0x0fdd},
+	{0x20da, 0x86b8},
+	{0x20dc, 0x50e0},
+	{0x20de, 0x0020},
+	{0x20e0, 0x5100},
+	{0x20e2, 0x3143},
+	{0x20e4, 0x5121},
+	{0x20e6, 0x7800},
+	{0x20e8, 0x3140},
+	{0x20ea, 0x01c4},
+	{0x20ec, 0x01c1},
+	{0x20ee, 0x01c0},
+	{0x20f0, 0x01c4},
+	{0x20f2, 0x2700},
+	{0x20f4, 0x3d40},
+	{0x20f6, 0x7800},
+	{0x20f8, 0xffff},
+	{0x27fe, 0xe000},
+	{0x3000, 0x60f8},
+	{0x3002, 0x187f},
+	{0x3004, 0x7060},
+	{0x3006, 0x0114},
+	{0x3008, 0x60b0},
+	{0x300a, 0x1473},
+	{0x300c, 0x0013},
+	{0x300e, 0x140f},
+	{0x3010, 0x0040},
+	{0x3012, 0x100f},
+	{0x3014, 0x60f8},
+	{0x3016, 0x187f},
+	{0x3018, 0x7060},
+	{0x301a, 0x0114},
+	{0x301c, 0x60b0},
+	{0x301e, 0x1473},
+	{0x3020, 0x0013},
+	{0x3022, 0x140f},
+	{0x3024, 0x0040},
+	{0x3026, 0x000f},
+
+	{0x0b00, 0x0000},
+	{0x0b02, 0x0045},
+	{0x0b04, 0xb405},
+	{0x0b06, 0xc403},
+	{0x0b08, 0x0081},
+	{0x0b0a, 0x8252},
+	{0x0b0c, 0xf814},
+	{0x0b0e, 0xc618},
+	{0x0b10, 0xa828},
+	{0x0b12, 0x004c},
+	{0x0b14, 0x4068},
+	{0x0b16, 0x0000},
+	{0x0f30, 0x5b15},
+	{0x0f32, 0x7067},
+	{0x0954, 0x0009},
+	{0x0956, 0x0000},
+	{0x0958, 0xbb80},
+	{0x095a, 0x5140},
+	{0x0c00, 0x1110},
+	{0x0c02, 0x0011},
+	{0x0c04, 0x0000},
+	{0x0c06, 0x0200},
+	{0x0c10, 0x0040},
+	{0x0c12, 0x0040},
+	{0x0c14, 0x0040},
+	{0x0c16, 0x0040},
+	{0x0a10, 0x4000},
+	{0x3068, 0xf800},
+	{0x306a, 0xf876},
+	{0x006c, 0x0000},
+	{0x005e, 0x0200},
+	{0x000e, 0x0100},
+	{0x0e0a, 0x0001},
+	{0x004a, 0x0100},
+	{0x004c, 0x0000},
+	{0x004e, 0x0100},
+	{0x000c, 0x0022},
+	{0x0008, 0x0b00},
+	{0x005a, 0x0202},
+	{0x0012, 0x000e},
+	{0x0018, 0x0a33},
+	{0x0022, 0x0008},
+	{0x0028, 0x0017},
+	{0x0024, 0x0028},
+	{0x002a, 0x002d},
+	{0x0026, 0x0030},
+	{0x002c, 0x07c9},
+	{0x002e, 0x1111},
+	{0x0030, 0x1111},
+	{0x0032, 0x1111},
+	{0x0006, 0x07bc},
+	{0x0a22, 0x0000},
+	{0x0a12, 0x0a20},
+	{0x0a14, 0x0798},
+	{0x003e, 0x0000},
+	{0x0074, 0x080e},
+	{0x0070, 0x0407},
+	{0x0002, 0x0000},
+	{0x0a02, 0x0100},
+	{0x0a24, 0x0100},
+	{0x0046, 0x0000},
+	{0x0076, 0x0000},
+	{0x0060, 0x0000},
+	{0x0062, 0x0530},
+	{0x0064, 0x0500},
+	{0x0066, 0x0530},
+	{0x0068, 0x0500},
+	{0x0122, 0x0300},
+	{0x015a, 0xff08},
+	{0x0804, 0x0300},
+	{0x0806, 0x0100},
+	{0x005c, 0x0102},
+	{0x0a1a, 0x0800},
+};
+
+static const struct hi556_reg mode_2592x1944_regs[] = {
+	{0x0a00, 0x0000},
+	{0x0b0a, 0x8252},
+	{0x0f30, 0x5b15},
+	{0x0f32, 0x7067},
+	{0x004a, 0x0100},
+	{0x004c, 0x0000},
+	{0x004e, 0x0100},
+	{0x000c, 0x0022},
+	{0x0008, 0x0b00},
+	{0x005a, 0x0202},
+	{0x0012, 0x000e},
+	{0x0018, 0x0a33},
+	{0x0022, 0x0008},
+	{0x0028, 0x0017},
+	{0x0024, 0x0028},
+	{0x002a, 0x002d},
+	{0x0026, 0x0030},
+	{0x002c, 0x07c9},
+	{0x002e, 0x1111},
+	{0x0030, 0x1111},
+	{0x0032, 0x1111},
+	{0x0006, 0x0814},
+	{0x0a22, 0x0000},
+	{0x0a12, 0x0a20},
+	{0x0a14, 0x0798},
+	{0x003e, 0x0000},
+	{0x0074, 0x0812},
+	{0x0070, 0x0409},
+	{0x0804, 0x0300},
+	{0x0806, 0x0100},
+	{0x0a04, 0x014a},
+	{0x090c, 0x0fdc},
+	{0x090e, 0x002d},
+
+	{0x0902, 0x4319},
+	{0x0914, 0xc10a},
+	{0x0916, 0x071f},
+	{0x0918, 0x0408},
+	{0x091a, 0x0c0d},
+	{0x091c, 0x0f09},
+	{0x091e, 0x0a00},
+	{0x0958, 0xbb80},
+};
+
+static const struct hi556_reg mode_1296x972_regs[] = {
+	{0x0a00, 0x0000},
+	{0x0b0a, 0x8259},
+	{0x0f30, 0x5b15},
+	{0x0f32, 0x7167},
+	{0x004a, 0x0100},
+	{0x004c, 0x0000},
+	{0x004e, 0x0100},
+	{0x000c, 0x0122},
+	{0x0008, 0x0b00},
+	{0x005a, 0x0404},
+	{0x0012, 0x000c},
+	{0x0018, 0x0a33},
+	{0x0022, 0x0008},
+	{0x0028, 0x0017},
+	{0x0024, 0x0022},
+	{0x002a, 0x002b},
+	{0x0026, 0x0030},
+	{0x002c, 0x07c9},
+	{0x002e, 0x3311},
+	{0x0030, 0x3311},
+	{0x0032, 0x3311},
+	{0x0006, 0x0814},
+	{0x0a22, 0x0000},
+	{0x0a12, 0x0510},
+	{0x0a14, 0x03cc},
+	{0x003e, 0x0000},
+	{0x0074, 0x0812},
+	{0x0070, 0x0409},
+	{0x0804, 0x0308},
+	{0x0806, 0x0100},
+	{0x0a04, 0x016a},
+	{0x090e, 0x0010},
+	{0x090c, 0x09c0},
+
+	{0x0902, 0x4319},
+	{0x0914, 0xc106},
+	{0x0916, 0x040e},
+	{0x0918, 0x0304},
+	{0x091a, 0x0708},
+	{0x091c, 0x0e06},
+	{0x091e, 0x0300},
+	{0x0958, 0xbb80},
+};
+
+static const char * const hi556_test_pattern_menu[] = {
+	"Disabled",
+	"Solid Colour",
+	"100% Colour Bars",
+	"Fade To Grey Colour Bars",
+	"PN9",
+	"Gradient Horizontal",
+	"Gradient Vertical",
+	"Check Board",
+	"Slant Pattern",
+};
+
+static const s64 link_freq_menu_items[] = {
+	HI556_LINK_FREQ_437MHZ,
+};
+
+static const struct hi556_link_freq_config link_freq_configs[] = {
+	[HI556_LINK_FREQ_437MHZ_INDEX] = {
+		.reg_list = {
+			.num_of_regs = ARRAY_SIZE(mipi_data_rate_874mbps),
+			.regs = mipi_data_rate_874mbps,
+		}
+	}
+};
+
+static const struct hi556_mode supported_modes[] = {
+	{
+		.width = 2592,
+		.height = 1944,
+		.fll_def = HI556_FLL_30FPS,
+		.fll_min = HI556_FLL_30FPS_MIN,
+		.llp = 0x0b00,
+		.reg_list = {
+			.num_of_regs = ARRAY_SIZE(mode_2592x1944_regs),
+			.regs = mode_2592x1944_regs,
+		},
+		.link_freq_index = HI556_LINK_FREQ_437MHZ_INDEX,
+	},
+	{
+		.width = 1296,
+		.height = 972,
+		.fll_def = HI556_FLL_30FPS,
+		.fll_min = HI556_FLL_30FPS_MIN,
+		.llp = 0x0b00,
+		.reg_list = {
+			.num_of_regs = ARRAY_SIZE(mode_1296x972_regs),
+			.regs = mode_1296x972_regs,
+		},
+		.link_freq_index = HI556_LINK_FREQ_437MHZ_INDEX,
+	}
+};
+
+struct hi556 {
+	struct v4l2_subdev sd;
+	struct media_pad pad;
+	struct v4l2_ctrl_handler ctrl_handler;
+
+	/* V4L2 Controls */
+	struct v4l2_ctrl *link_freq;
+	struct v4l2_ctrl *pixel_rate;
+	struct v4l2_ctrl *vblank;
+	struct v4l2_ctrl *hblank;
+	struct v4l2_ctrl *exposure;
+
+	/* Current mode */
+	const struct hi556_mode *cur_mode;
+
+	/* To serialize asynchronus callbacks */
+	struct mutex mutex;
+
+	/* Streaming on/off */
+	bool streaming;
+};
+
+static u64 to_pixel_rate(u32 f_index)
+{
+	u64 pixel_rate = link_freq_menu_items[f_index] * 2 * HI556_DATA_LANES;
+
+	do_div(pixel_rate, HI556_RGB_DEPTH);
+
+	return pixel_rate;
+}
+
+static int hi556_read_reg(struct hi556 *hi556, u16 reg, u16 len, u32 *val)
+{
+	struct i2c_client *client = v4l2_get_subdevdata(&hi556->sd);
+	struct i2c_msg msgs[2];
+	u8 addr_buf[2];
+	u8 data_buf[4] = {0};
+	int ret;
+
+	if (len > 4)
+		return -EINVAL;
+
+	put_unaligned_be16(reg, addr_buf);
+	msgs[0].addr = client->addr;
+	msgs[0].flags = 0;
+	msgs[0].len = sizeof(addr_buf);
+	msgs[0].buf = addr_buf;
+	msgs[1].addr = client->addr;
+	msgs[1].flags = I2C_M_RD;
+	msgs[1].len = len;
+	msgs[1].buf = &data_buf[4 - len];
+
+	ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
+	if (ret != ARRAY_SIZE(msgs))
+		return -EIO;
+
+	*val = get_unaligned_be32(data_buf);
+
+	return 0;
+}
+
+static int hi556_write_reg(struct hi556 *hi556, u16 reg, u16 len, u32 val)
+{
+	struct i2c_client *client = v4l2_get_subdevdata(&hi556->sd);
+	u8 buf[6];
+
+	if (len > 4)
+		return -EINVAL;
+
+	put_unaligned_be16(reg, buf);
+	put_unaligned_be32(val << 8 * (4 - len), buf + 2);
+	if (i2c_master_send(client, buf, len + 2) != len + 2)
+		return -EIO;
+
+	return 0;
+}
+
+static int hi556_write_reg_list(struct hi556 *hi556,
+				 const struct hi556_reg_list *r_list)
+{
+	struct i2c_client *client = v4l2_get_subdevdata(&hi556->sd);
+	unsigned int i;
+	int ret;
+
+	for (i = 0; i < r_list->num_of_regs; i++) {
+		ret = hi556_write_reg(hi556, r_list->regs[i].address,
+			HI556_REG_VALUE_16BIT, r_list->regs[i].val);
+		if (ret) {
+			dev_err_ratelimited(&client->dev,
+				    "failed to write reg 0x%4.4x. error = %d",
+				    r_list->regs[i].address, ret);
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+static int hi556_update_digital_gain(struct hi556 *hi556, u32 d_gain)
+{
+	int ret;
+
+	ret = hi556_write_reg(hi556, HI556_REG_MWB_GR_GAIN,
+			       HI556_REG_VALUE_16BIT, d_gain);
+	if (ret)
+		return ret;
+
+	ret = hi556_write_reg(hi556, HI556_REG_MWB_GB_GAIN,
+			       HI556_REG_VALUE_16BIT, d_gain);
+	if (ret)
+		return ret;
+
+	ret = hi556_write_reg(hi556, HI556_REG_MWB_R_GAIN,
+			       HI556_REG_VALUE_16BIT, d_gain);
+	if (ret)
+		return ret;
+
+	return hi556_write_reg(hi556, HI556_REG_MWB_B_GAIN,
+				HI556_REG_VALUE_16BIT, d_gain);
+}
+
+static int hi556_test_pattern(struct hi556 *hi556, u32 pattern)
+{
+	int ret;
+	u32 val;
+
+	if (pattern) {
+		ret = hi556_read_reg(hi556, HI556_REG_ISP,
+				     HI556_REG_VALUE_08BIT, &val);
+		if (ret)
+			return ret;
+
+		ret = hi556_write_reg(hi556, HI556_REG_ISP,
+			HI556_REG_VALUE_08BIT, val | HI556_REG_ISP_TPG_EN);
+		if (ret)
+			return ret;
+	}
+
+	return hi556_write_reg(hi556, HI556_REG_TEST_PATTERN,
+				HI556_REG_VALUE_08BIT, pattern);
+}
+
+static int hi556_set_ctrl(struct v4l2_ctrl *ctrl)
+{
+	struct hi556 *hi556 = container_of(ctrl->handler,
+					     struct hi556, ctrl_handler);
+	struct i2c_client *client = v4l2_get_subdevdata(&hi556->sd);
+	s64 exposure_max;
+	int ret = 0;
+
+	/* Propagate change of current control to all related controls */
+	if (ctrl->id == V4L2_CID_VBLANK) {
+		/* Update max exposure while meeting expected vblanking */
+		exposure_max = hi556->cur_mode->height + ctrl->val -
+			       HI556_EXPOSURE_MAX_MARGIN;
+		__v4l2_ctrl_modify_range(hi556->exposure,
+					 hi556->exposure->minimum,
+					 exposure_max, hi556->exposure->step,
+					 exposure_max);
+	}
+
+	/* V4L2 controls values will be applied only when power is already up */
+	if (!pm_runtime_get_if_in_use(&client->dev))
+		return 0;
+
+	switch (ctrl->id) {
+	case V4L2_CID_ANALOGUE_GAIN:
+		ret = hi556_write_reg(hi556, HI556_REG_ANALOG_GAIN,
+				       HI556_REG_VALUE_16BIT, ctrl->val);
+		break;
+
+	case V4L2_CID_DIGITAL_GAIN:
+		ret = hi556_update_digital_gain(hi556, ctrl->val);
+		break;
+
+	case V4L2_CID_EXPOSURE:
+		ret = hi556_write_reg(hi556, HI556_REG_EXPOSURE,
+				       HI556_REG_VALUE_16BIT, ctrl->val);
+		break;
+
+	case V4L2_CID_VBLANK:
+		/* Update FLL that meets expected vertical blanking */
+		ret = hi556_write_reg(hi556, HI556_REG_FLL,
+				       HI556_REG_VALUE_16BIT,
+				       hi556->cur_mode->height + ctrl->val);
+		break;
+
+	case V4L2_CID_TEST_PATTERN:
+		ret = hi556_test_pattern(hi556, ctrl->val);
+		break;
+
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+	pm_runtime_put(&client->dev);
+
+	return ret;
+}
+
+static const struct v4l2_ctrl_ops hi556_ctrl_ops = {
+	.s_ctrl = hi556_set_ctrl,
+};
+
+static int hi556_init_controls(struct hi556 *hi556)
+{
+	struct v4l2_ctrl_handler *ctrl_hdlr;
+	s64 exposure_max, h_blank;
+	int ret;
+
+	ctrl_hdlr = &hi556->ctrl_handler;
+	ret = v4l2_ctrl_handler_init(ctrl_hdlr, 8);
+	if (ret)
+		return ret;
+
+	ctrl_hdlr->lock = &hi556->mutex;
+	hi556->link_freq = v4l2_ctrl_new_int_menu(ctrl_hdlr, &hi556_ctrl_ops,
+					   V4L2_CID_LINK_FREQ,
+					   ARRAY_SIZE(link_freq_menu_items) - 1,
+					   0, link_freq_menu_items);
+	if (hi556->link_freq)
+		hi556->link_freq->flags |= V4L2_CTRL_FLAG_READ_ONLY;
+
+	hi556->pixel_rate = v4l2_ctrl_new_std(ctrl_hdlr, &hi556_ctrl_ops,
+				  V4L2_CID_PIXEL_RATE, 0,
+				  to_pixel_rate(HI556_LINK_FREQ_437MHZ_INDEX),
+				  1,
+				  to_pixel_rate(HI556_LINK_FREQ_437MHZ_INDEX));
+	hi556->vblank = v4l2_ctrl_new_std(ctrl_hdlr, &hi556_ctrl_ops,
+			  V4L2_CID_VBLANK,
+			  hi556->cur_mode->fll_min - hi556->cur_mode->height,
+			  HI556_FLL_MAX - hi556->cur_mode->height, 1,
+			  hi556->cur_mode->fll_def - hi556->cur_mode->height);
+
+	h_blank = hi556->cur_mode->llp - hi556->cur_mode->width;
+
+	hi556->hblank = v4l2_ctrl_new_std(ctrl_hdlr, &hi556_ctrl_ops,
+					   V4L2_CID_HBLANK, h_blank, h_blank, 1,
+					   h_blank);
+	if (hi556->hblank)
+		hi556->hblank->flags |= V4L2_CTRL_FLAG_READ_ONLY;
+
+	v4l2_ctrl_new_std(ctrl_hdlr, &hi556_ctrl_ops, V4L2_CID_ANALOGUE_GAIN,
+			  HI556_ANAL_GAIN_MIN, HI556_ANAL_GAIN_MAX,
+			  HI556_ANAL_GAIN_STEP, HI556_ANAL_GAIN_MIN);
+	v4l2_ctrl_new_std(ctrl_hdlr, &hi556_ctrl_ops, V4L2_CID_DIGITAL_GAIN,
+			  HI556_DGTL_GAIN_MIN, HI556_DGTL_GAIN_MAX,
+			  HI556_DGTL_GAIN_STEP, HI556_DGTL_GAIN_DEFAULT);
+	exposure_max = hi556->cur_mode->fll_def - HI556_EXPOSURE_MAX_MARGIN;
+	hi556->exposure = v4l2_ctrl_new_std(ctrl_hdlr, &hi556_ctrl_ops,
+					     V4L2_CID_EXPOSURE,
+					     HI556_EXPOSURE_MIN, exposure_max,
+					     HI556_EXPOSURE_STEP,
+					     exposure_max);
+	v4l2_ctrl_new_std_menu_items(ctrl_hdlr, &hi556_ctrl_ops,
+				     V4L2_CID_TEST_PATTERN,
+				     ARRAY_SIZE(hi556_test_pattern_menu) - 1,
+				     0, 0, hi556_test_pattern_menu);
+	if (ctrl_hdlr->error)
+		return ctrl_hdlr->error;
+
+	hi556->sd.ctrl_handler = ctrl_hdlr;
+
+	return 0;
+}
+
+static void hi556_assign_pad_format(const struct hi556_mode *mode,
+				     struct v4l2_mbus_framefmt *fmt)
+{
+	fmt->width = mode->width;
+	fmt->height = mode->height;
+	fmt->code = MEDIA_BUS_FMT_SGRBG10_1X10;
+	fmt->field = V4L2_FIELD_NONE;
+}
+
+static int hi556_start_streaming(struct hi556 *hi556)
+{
+	struct i2c_client *client = v4l2_get_subdevdata(&hi556->sd);
+	const struct hi556_reg_list *reg_list;
+	int link_freq_index, ret;
+
+	link_freq_index = hi556->cur_mode->link_freq_index;
+	reg_list = &link_freq_configs[link_freq_index].reg_list;
+	ret = hi556_write_reg_list(hi556, reg_list);
+	if (ret) {
+		dev_err(&client->dev, "failed to set plls");
+		return ret;
+	}
+
+	reg_list = &hi556->cur_mode->reg_list;
+	ret = hi556_write_reg_list(hi556, reg_list);
+	if (ret) {
+		dev_err(&client->dev, "failed to set mode");
+		return ret;
+	}
+
+	ret = __v4l2_ctrl_handler_setup(hi556->sd.ctrl_handler);
+	if (ret)
+		return ret;
+
+	ret = hi556_write_reg(hi556, HI556_REG_MODE_SELECT,
+			       HI556_REG_VALUE_16BIT, HI556_MODE_STREAMING);
+
+	if (ret) {
+		dev_err(&client->dev, "failed to set stream");
+		return ret;
+	}
+
+	return 0;
+}
+
+static void hi556_stop_streaming(struct hi556 *hi556)
+{
+	struct i2c_client *client = v4l2_get_subdevdata(&hi556->sd);
+
+	if (hi556_write_reg(hi556, HI556_REG_MODE_SELECT,
+			     HI556_REG_VALUE_16BIT, HI556_MODE_STANDBY))
+		dev_err(&client->dev, "failed to set stream");
+}
+
+static int hi556_set_stream(struct v4l2_subdev *sd, int enable)
+{
+	struct hi556 *hi556 = to_hi556(sd);
+	struct i2c_client *client = v4l2_get_subdevdata(sd);
+	int ret = 0;
+
+	if (hi556->streaming == enable)
+		return 0;
+
+	mutex_lock(&hi556->mutex);
+	if (enable) {
+		ret = pm_runtime_get_sync(&client->dev);
+		if (ret < 0) {
+			pm_runtime_put_noidle(&client->dev);
+			mutex_unlock(&hi556->mutex);
+			return ret;
+		}
+
+		ret = hi556_start_streaming(hi556);
+		if (ret) {
+			enable = 0;
+			hi556_stop_streaming(hi556);
+			pm_runtime_put(&client->dev);
+		}
+	} else {
+		hi556_stop_streaming(hi556);
+		pm_runtime_put(&client->dev);
+	}
+
+	hi556->streaming = enable;
+	mutex_unlock(&hi556->mutex);
+
+	return ret;
+}
+
+static int __maybe_unused hi556_suspend(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct v4l2_subdev *sd = i2c_get_clientdata(client);
+	struct hi556 *hi556 = to_hi556(sd);
+
+	mutex_lock(&hi556->mutex);
+	if (hi556->streaming)
+		hi556_stop_streaming(hi556);
+
+	mutex_unlock(&hi556->mutex);
+
+	return 0;
+}
+
+static int __maybe_unused hi556_resume(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct v4l2_subdev *sd = i2c_get_clientdata(client);
+	struct hi556 *hi556 = to_hi556(sd);
+	int ret;
+
+	mutex_lock(&hi556->mutex);
+	if (hi556->streaming) {
+		ret = hi556_start_streaming(hi556);
+		if (ret)
+			goto error;
+	}
+
+	mutex_unlock(&hi556->mutex);
+
+	return 0;
+
+error:
+	hi556_stop_streaming(hi556);
+	hi556->streaming = 0;
+	mutex_unlock(&hi556->mutex);
+	return ret;
+}
+
+static int hi556_set_format(struct v4l2_subdev *sd,
+			     struct v4l2_subdev_pad_config *cfg,
+			     struct v4l2_subdev_format *fmt)
+{
+	struct hi556 *hi556 = to_hi556(sd);
+	const struct hi556_mode *mode;
+	s32 vblank_def, h_blank;
+
+	mode = v4l2_find_nearest_size(supported_modes,
+				      ARRAY_SIZE(supported_modes), width,
+				      height, fmt->format.width,
+				      fmt->format.height);
+
+	mutex_lock(&hi556->mutex);
+	hi556_assign_pad_format(mode, &fmt->format);
+	if (fmt->which == V4L2_SUBDEV_FORMAT_TRY) {
+		*v4l2_subdev_get_try_format(sd, cfg, fmt->pad) = fmt->format;
+	} else {
+		hi556->cur_mode = mode;
+		__v4l2_ctrl_s_ctrl(hi556->link_freq, mode->link_freq_index);
+		__v4l2_ctrl_s_ctrl_int64(hi556->pixel_rate,
+					 to_pixel_rate(mode->link_freq_index));
+
+		/* Update limits and set FPS to default */
+		vblank_def = mode->fll_def - mode->height;
+		__v4l2_ctrl_modify_range(hi556->vblank,
+					 mode->fll_min - mode->height,
+					 HI556_FLL_MAX - mode->height, 1,
+					 vblank_def);
+		__v4l2_ctrl_s_ctrl(hi556->vblank, vblank_def);
+
+		h_blank = hi556->cur_mode->llp - hi556->cur_mode->width;
+
+		__v4l2_ctrl_modify_range(hi556->hblank, h_blank, h_blank, 1,
+					 h_blank);
+	}
+
+	mutex_unlock(&hi556->mutex);
+
+	return 0;
+}
+
+static int hi556_get_format(struct v4l2_subdev *sd,
+			     struct v4l2_subdev_pad_config *cfg,
+			     struct v4l2_subdev_format *fmt)
+{
+	struct hi556 *hi556 = to_hi556(sd);
+
+	mutex_lock(&hi556->mutex);
+	if (fmt->which == V4L2_SUBDEV_FORMAT_TRY)
+		fmt->format = *v4l2_subdev_get_try_format(&hi556->sd, cfg,
+							  fmt->pad);
+	else
+		hi556_assign_pad_format(hi556->cur_mode, &fmt->format);
+
+	mutex_unlock(&hi556->mutex);
+
+	return 0;
+}
+
+static int hi556_enum_mbus_code(struct v4l2_subdev *sd,
+				 struct v4l2_subdev_pad_config *cfg,
+				 struct v4l2_subdev_mbus_code_enum *code)
+{
+	if (code->index > 0)
+		return -EINVAL;
+
+	code->code = MEDIA_BUS_FMT_SGRBG10_1X10;
+
+	return 0;
+}
+
+static int hi556_enum_frame_size(struct v4l2_subdev *sd,
+				  struct v4l2_subdev_pad_config *cfg,
+				  struct v4l2_subdev_frame_size_enum *fse)
+{
+	if (fse->index >= ARRAY_SIZE(supported_modes))
+		return -EINVAL;
+
+	if (fse->code != MEDIA_BUS_FMT_SGRBG10_1X10)
+		return -EINVAL;
+
+	fse->min_width = supported_modes[fse->index].width;
+	fse->max_width = fse->min_width;
+	fse->min_height = supported_modes[fse->index].height;
+	fse->max_height = fse->min_height;
+
+	return 0;
+}
+
+static int hi556_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
+{
+	struct hi556 *hi556 = to_hi556(sd);
+
+	mutex_lock(&hi556->mutex);
+	hi556_assign_pad_format(&supported_modes[0],
+				 v4l2_subdev_get_try_format(sd, fh->pad, 0));
+	mutex_unlock(&hi556->mutex);
+
+	return 0;
+}
+
+static const struct v4l2_subdev_video_ops hi556_video_ops = {
+	.s_stream = hi556_set_stream,
+};
+
+static const struct v4l2_subdev_pad_ops hi556_pad_ops = {
+	.set_fmt = hi556_set_format,
+	.get_fmt = hi556_get_format,
+	.enum_mbus_code = hi556_enum_mbus_code,
+	.enum_frame_size = hi556_enum_frame_size,
+};
+
+static const struct v4l2_subdev_ops hi556_subdev_ops = {
+	.video = &hi556_video_ops,
+	.pad = &hi556_pad_ops,
+};
+
+static const struct media_entity_operations hi556_subdev_entity_ops = {
+	.link_validate = v4l2_subdev_link_validate,
+};
+
+static const struct v4l2_subdev_internal_ops hi556_internal_ops = {
+	.open = hi556_open,
+};
+
+static int hi556_identify_module(struct hi556 *hi556)
+{
+	struct i2c_client *client = v4l2_get_subdevdata(&hi556->sd);
+	int ret;
+	u32 val;
+
+	ret = hi556_read_reg(hi556, HI556_REG_CHIP_ID,
+			     HI556_REG_VALUE_16BIT, &val);
+	if (ret)
+		return ret;
+
+	if (val != HI556_CHIP_ID) {
+		dev_err(&client->dev, "chip id mismatch: %x!=%x",
+			HI556_CHIP_ID, val);
+		return -ENXIO;
+	}
+
+	return 0;
+}
+
+static int hi556_check_hwcfg(struct device *dev)
+{
+	struct fwnode_handle *ep;
+	struct fwnode_handle *fwnode = dev_fwnode(dev);
+	struct v4l2_fwnode_endpoint bus_cfg = {
+		.bus_type = V4L2_MBUS_CSI2_DPHY
+	};
+	u32 mclk;
+	int ret = 0;
+	unsigned int i, j;
+
+	if (!fwnode)
+		return -ENXIO;
+
+	ret = fwnode_property_read_u32(fwnode, "clock-frequency", &mclk);
+	if (ret) {
+		dev_err(dev, "can't get clock frequency");
+		return ret;
+	}
+
+	if (mclk != HI556_MCLK) {
+		dev_err(dev, "external clock %d is not supported", mclk);
+		return -EINVAL;
+	}
+
+	ep = fwnode_graph_get_next_endpoint(fwnode, NULL);
+	if (!ep)
+		return -ENXIO;
+
+	ret = v4l2_fwnode_endpoint_alloc_parse(ep, &bus_cfg);
+	fwnode_handle_put(ep);
+	if (ret)
+		return ret;
+
+	if (bus_cfg.bus.mipi_csi2.num_data_lanes != 2) {
+		dev_err(dev, "number of CSI2 data lanes %d is not supported",
+			bus_cfg.bus.mipi_csi2.num_data_lanes);
+		ret = -EINVAL;
+		goto check_hwcfg_error;
+	}
+
+	if (!bus_cfg.nr_of_link_frequencies) {
+		dev_err(dev, "no link frequencies defined");
+		ret = -EINVAL;
+		goto check_hwcfg_error;
+	}
+
+	for (i = 0; i < ARRAY_SIZE(link_freq_menu_items); i++) {
+		for (j = 0; j < bus_cfg.nr_of_link_frequencies; j++) {
+			if (link_freq_menu_items[i] ==
+				bus_cfg.link_frequencies[j])
+				break;
+		}
+
+		if (j == bus_cfg.nr_of_link_frequencies) {
+			dev_err(dev, "no link frequency %lld supported",
+				link_freq_menu_items[i]);
+			ret = -EINVAL;
+			goto check_hwcfg_error;
+		}
+	}
+
+check_hwcfg_error:
+	v4l2_fwnode_endpoint_free(&bus_cfg);
+
+	return ret;
+}
+
+static int hi556_remove(struct i2c_client *client)
+{
+	struct v4l2_subdev *sd = i2c_get_clientdata(client);
+	struct hi556 *hi556 = to_hi556(sd);
+
+	v4l2_async_unregister_subdev(sd);
+	media_entity_cleanup(&sd->entity);
+	v4l2_ctrl_handler_free(sd->ctrl_handler);
+	pm_runtime_disable(&client->dev);
+	mutex_destroy(&hi556->mutex);
+
+	return 0;
+}
+
+static int hi556_probe(struct i2c_client *client)
+{
+	struct hi556 *hi556;
+	int ret;
+
+	ret = hi556_check_hwcfg(&client->dev);
+	if (ret) {
+		dev_err(&client->dev, "failed to check HW configuration: %d",
+			ret);
+		return ret;
+	}
+
+	hi556 = devm_kzalloc(&client->dev, sizeof(*hi556), GFP_KERNEL);
+	if (!hi556)
+		return -ENOMEM;
+
+	v4l2_i2c_subdev_init(&hi556->sd, client, &hi556_subdev_ops);
+	ret = hi556_identify_module(hi556);
+	if (ret) {
+		dev_err(&client->dev, "failed to find sensor: %d", ret);
+		return ret;
+	}
+
+	mutex_init(&hi556->mutex);
+	hi556->cur_mode = &supported_modes[0];
+	ret = hi556_init_controls(hi556);
+	if (ret) {
+		dev_err(&client->dev, "failed to init controls: %d", ret);
+		goto probe_error_v4l2_ctrl_handler_free;
+	}
+
+	hi556->sd.internal_ops = &hi556_internal_ops;
+	hi556->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
+	hi556->sd.entity.ops = &hi556_subdev_entity_ops;
+	hi556->sd.entity.function = MEDIA_ENT_F_CAM_SENSOR;
+	hi556->pad.flags = MEDIA_PAD_FL_SOURCE;
+	ret = media_entity_pads_init(&hi556->sd.entity, 1, &hi556->pad);
+	if (ret) {
+		dev_err(&client->dev, "failed to init entity pads: %d", ret);
+		goto probe_error_v4l2_ctrl_handler_free;
+	}
+
+	ret = v4l2_async_register_subdev_sensor_common(&hi556->sd);
+	if (ret < 0) {
+		dev_err(&client->dev, "failed to register V4L2 subdev: %d",
+			ret);
+		goto probe_error_media_entity_cleanup;
+	}
+
+	pm_runtime_set_active(&client->dev);
+	pm_runtime_enable(&client->dev);
+	pm_runtime_idle(&client->dev);
+
+	return 0;
+
+probe_error_media_entity_cleanup:
+	media_entity_cleanup(&hi556->sd.entity);
+
+probe_error_v4l2_ctrl_handler_free:
+	v4l2_ctrl_handler_free(hi556->sd.ctrl_handler);
+	mutex_destroy(&hi556->mutex);
+
+	return ret;
+}
+
+static const struct dev_pm_ops hi556_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(hi556_suspend, hi556_resume)
+};
+
+#ifdef CONFIG_ACPI
+static const struct acpi_device_id hi556_acpi_ids[] = {
+	{"INT3537"},
+	{}
+};
+
+MODULE_DEVICE_TABLE(acpi, hi556_acpi_ids);
+#endif
+
+static struct i2c_driver hi556_i2c_driver = {
+	.driver = {
+		.name = "hi556",
+		.pm = &hi556_pm_ops,
+		.acpi_match_table = ACPI_PTR(hi556_acpi_ids),
+	},
+	.probe_new = hi556_probe,
+	.remove = hi556_remove,
+};
+
+module_i2c_driver(hi556_i2c_driver);
+
+MODULE_AUTHOR("Shawn Tu <shawnx.tu@intel.com>");
+MODULE_DESCRIPTION("Hynix HI556 sensor driver");
+MODULE_LICENSE("GPL v2");
-- 
2.7.4