[PATCH 0/3] media: i2c: ov9282: Modernize driver with CCI and streams API

[PATCH 0/3] media: i2c: ov9282: Modernize driver with CCI and streams API

[Xiaolei Wang]

This series modernizes the ov9282 driver by:

1. Converting to the common CCI (Camera Control Interface) register
   access helpers, which simplifies the code by removing custom I2C
   register access functions.

2. Switching to use the V4L2 sub-device state lock instead of a
   private mutex, improving integration with the V4L2 framework.

3. Migrating from the legacy s_stream callback to the modern
   enable_streams/disable_streams callbacks, providing better support
   for multiplexed streams.

These changes reduce code complexity, improve maintainability, and
align the driver with current V4L2 best practices.

I verified each patch on the Raspberry Pi 5 platform.


Xiaolei Wang (3):
  media: i2c: ov9282: Convert to CCI register access helpers
  media: i2c: ov9282: Switch to using the sub-device state lock
  media: i2c: ov9282: switch to {enable,disable}_streams

 drivers/media/i2c/Kconfig  |   1 +
 drivers/media/i2c/ov9282.c | 406 +++++++++----------------------------
 2 files changed, 97 insertions(+), 310 deletions(-)

-- 
2.43.0

[PATCH 1/3] media: i2c: ov9282: Convert to CCI register access helpers

[Xiaolei Wang]

Use the new common CCI register access helpers to replace the private
register access helpers in the ov9282 driver. This simplifies the driver
by reducing the amount of code.

Signed-off-by: Xiaolei Wang <xiaolei.wang@windriver.com>
---
 drivers/media/i2c/Kconfig  |   1 +
 drivers/media/i2c/ov9282.c | 290 ++++++++-----------------------------
 2 files changed, 62 insertions(+), 229 deletions(-)

diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
index 5eb1e0e0a87a..3027e71fd8fb 100644
--- a/drivers/media/i2c/Kconfig
+++ b/drivers/media/i2c/Kconfig
@@ -690,6 +690,7 @@ config VIDEO_OV8865
 config VIDEO_OV9282
 	tristate "OmniVision OV9282 sensor support"
 	depends on OF_GPIO
+	select V4L2_CCI_I2C
 	help
 	  This is a Video4Linux2 sensor driver for the OmniVision
 	  OV9282 camera sensor.
diff --git a/drivers/media/i2c/ov9282.c b/drivers/media/i2c/ov9282.c
index ded9b2044ff8..75e41a0f588e 100644
--- a/drivers/media/i2c/ov9282.c
+++ b/drivers/media/i2c/ov9282.c
@@ -12,38 +12,40 @@
 #include <linux/math.h>
 #include <linux/module.h>
 #include <linux/pm_runtime.h>
+#include <linux/regmap.h>
 #include <linux/regulator/consumer.h>
 
+#include <media/v4l2-cci.h>
 #include <media/v4l2-ctrls.h>
 #include <media/v4l2-event.h>
 #include <media/v4l2-fwnode.h>
 #include <media/v4l2-subdev.h>
 
 /* Streaming Mode */
-#define OV9282_REG_MODE_SELECT	0x0100
+#define OV9282_REG_MODE_SELECT	CCI_REG8(0x0100)
 #define OV9282_MODE_STANDBY	0x00
 #define OV9282_MODE_STREAMING	0x01
 
-#define OV9282_REG_PLL_CTRL_0D	0x030d
+#define OV9282_REG_PLL_CTRL_0D	CCI_REG8(0x030d)
 #define OV9282_PLL_CTRL_0D_RAW8		0x60
 #define OV9282_PLL_CTRL_0D_RAW10	0x50
 
-#define OV9282_REG_TIMING_HTS	0x380c
+#define OV9282_REG_TIMING_HTS	CCI_REG16(0x380c)
 #define OV9282_TIMING_HTS_MAX	0x7fff
 
 /* Lines per frame */
-#define OV9282_REG_LPFR		0x380e
+#define OV9282_REG_LPFR		CCI_REG16(0x380e)
 
 /* Chip ID */
-#define OV9282_REG_ID		0x300a
+#define OV9282_REG_ID		CCI_REG16(0x300a)
 #define OV9282_ID		0x9281
 
 /* Output enable registers */
-#define OV9282_REG_OUTPUT_ENABLE4	0x3004
+#define OV9282_REG_OUTPUT_ENABLE4	CCI_REG8(0x3004)
 #define OV9282_OUTPUT_ENABLE4_GPIO2	BIT(1)
 #define OV9282_OUTPUT_ENABLE4_D9	BIT(0)
 
-#define OV9282_REG_OUTPUT_ENABLE5	0x3005
+#define OV9282_REG_OUTPUT_ENABLE5	CCI_REG8(0x3005)
 #define OV9282_OUTPUT_ENABLE5_D8	BIT(7)
 #define OV9282_OUTPUT_ENABLE5_D7	BIT(6)
 #define OV9282_OUTPUT_ENABLE5_D6	BIT(5)
@@ -53,7 +55,7 @@
 #define OV9282_OUTPUT_ENABLE5_D2	BIT(1)
 #define OV9282_OUTPUT_ENABLE5_D1	BIT(0)
 
-#define OV9282_REG_OUTPUT_ENABLE6	0x3006
+#define OV9282_REG_OUTPUT_ENABLE6	CCI_REG8(0x3006)
 #define OV9282_OUTPUT_ENABLE6_D0	BIT(7)
 #define OV9282_OUTPUT_ENABLE6_PCLK	BIT(6)
 #define OV9282_OUTPUT_ENABLE6_HREF	BIT(5)
@@ -62,14 +64,14 @@
 #define OV9282_OUTPUT_ENABLE6_VSYNC	BIT(1)
 
 /* Exposure control */
-#define OV9282_REG_EXPOSURE	0x3500
+#define OV9282_REG_EXPOSURE	CCI_REG24(0x3500)
 #define OV9282_EXPOSURE_MIN	1
 #define OV9282_EXPOSURE_OFFSET	25
 #define OV9282_EXPOSURE_STEP	1
 #define OV9282_EXPOSURE_DEFAULT	0x0282
 
 /* AEC/AGC manual */
-#define OV9282_REG_AEC_MANUAL		0x3503
+#define OV9282_REG_AEC_MANUAL		CCI_REG8(0x3503)
 #define OV9282_DIGFRAC_GAIN_DELAY	BIT(6)
 #define OV9282_GAIN_CHANGE_DELAY	BIT(5)
 #define OV9282_GAIN_DELAY		BIT(4)
@@ -78,28 +80,28 @@
 #define OV9282_AEC_MANUAL_DEFAULT	0x00
 
 /* Analog gain control */
-#define OV9282_REG_AGAIN	0x3509
+#define OV9282_REG_AGAIN	CCI_REG8(0x3509)
 #define OV9282_AGAIN_MIN	0x10
 #define OV9282_AGAIN_MAX	0xff
 #define OV9282_AGAIN_STEP	1
 #define OV9282_AGAIN_DEFAULT	0x10
 
 /* Group hold register */
-#define OV9282_REG_HOLD		0x3308
+#define OV9282_REG_HOLD		CCI_REG8(0x3308)
 
-#define OV9282_REG_ANA_CORE_2	0x3662
+#define OV9282_REG_ANA_CORE_2	CCI_REG8(0x3662)
 #define OV9282_ANA_CORE2_RAW8	0x07
 #define OV9282_ANA_CORE2_RAW10	0x05
 
-#define OV9282_REG_TIMING_FORMAT_1	0x3820
-#define OV9282_REG_TIMING_FORMAT_2	0x3821
+#define OV9282_REG_TIMING_FORMAT_1	CCI_REG8(0x3820)
+#define OV9282_REG_TIMING_FORMAT_2	CCI_REG8(0x3821)
 #define OV9282_FLIP_BIT			BIT(2)
 
-#define OV9282_REG_MIPI_CTRL00	0x4800
+#define OV9282_REG_MIPI_CTRL00	CCI_REG8(0x4800)
 #define OV9282_GATED_CLOCK	BIT(5)
 
 /* Flash/Strobe control registers */
-#define OV9282_REG_STROBE_FRAME_SPAN		0x3925
+#define OV9282_REG_STROBE_FRAME_SPAN		CCI_REG32(0x3925)
 #define OV9282_STROBE_FRAME_SPAN_DEFAULT	0x0000001a
 
 /* Input clock rate */
@@ -139,16 +141,6 @@ static const char * const ov9282_supply_names[] = {
 
 #define OV9282_NUM_SUPPLIES ARRAY_SIZE(ov9282_supply_names)
 
-/**
- * struct ov9282_reg - ov9282 sensor register
- * @address: Register address
- * @val: Register value
- */
-struct ov9282_reg {
-	u16 address;
-	u8 val;
-};
-
 /**
  * struct ov9282_reg_list - ov9282 sensor register list
  * @num_of_regs: Number of registers in the list
@@ -156,7 +148,7 @@ struct ov9282_reg {
  */
 struct ov9282_reg_list {
 	u32 num_of_regs;
-	const struct ov9282_reg *regs;
+	const struct reg_sequence *regs;
 };
 
 /**
@@ -209,6 +201,7 @@ struct ov9282_mode {
 struct ov9282 {
 	struct device *dev;
 	struct v4l2_subdev sd;
+	struct regmap *regmap;
 	struct media_pad pad;
 	struct gpio_desc *reset_gpio;
 	struct clk *inclk;
@@ -241,7 +234,7 @@ static const s64 link_freq[] = {
  * register arrays as some settings are written as part of ov9282_power_on,
  * and the reset will clear them.
  */
-static const struct ov9282_reg common_regs[] = {
+static const struct reg_sequence common_regs[] = {
 	{0x0302, 0x32},
 	{0x030e, 0x02},
 	{0x3001, 0x00},
@@ -305,11 +298,6 @@ static const struct ov9282_reg common_regs[] = {
 	{0x5a08, 0x84},
 };
 
-static struct ov9282_reg_list common_regs_list = {
-	.num_of_regs = ARRAY_SIZE(common_regs),
-	.regs = common_regs,
-};
-
 #define MODE_1280_800		0
 #define MODE_1280_720		1
 #define MODE_640_400		2
@@ -317,7 +305,7 @@ static struct ov9282_reg_list common_regs_list = {
 #define DEFAULT_MODE		MODE_1280_720
 
 /* Sensor mode registers */
-static const struct ov9282_reg mode_1280x800_regs[] = {
+static const struct reg_sequence mode_1280x800_regs[] = {
 	{0x3778, 0x00},
 	{0x3800, 0x00},
 	{0x3801, 0x00},
@@ -348,7 +336,7 @@ static const struct ov9282_reg mode_1280x800_regs[] = {
 	{0x4509, 0x00},
 };
 
-static const struct ov9282_reg mode_1280x720_regs[] = {
+static const struct reg_sequence mode_1280x720_regs[] = {
 	{0x3778, 0x00},
 	{0x3800, 0x00},
 	{0x3801, 0x00},
@@ -379,7 +367,7 @@ static const struct ov9282_reg mode_1280x720_regs[] = {
 	{0x4509, 0x80},
 };
 
-static const struct ov9282_reg mode_640x400_regs[] = {
+static const struct reg_sequence mode_640x400_regs[] = {
 	{0x3778, 0x10},
 	{0x3800, 0x00},
 	{0x3801, 0x00},
@@ -485,97 +473,6 @@ static inline struct ov9282 *to_ov9282(struct v4l2_subdev *subdev)
 	return container_of(subdev, struct ov9282, sd);
 }
 
-/**
- * ov9282_read_reg() - Read registers.
- * @ov9282: pointer to ov9282 device
- * @reg: register address
- * @len: length of bytes to read. Max supported bytes is 4
- * @val: pointer to register value to be filled.
- *
- * Return: 0 if successful, error code otherwise.
- */
-static int ov9282_read_reg(struct ov9282 *ov9282, u16 reg, u32 len, u32 *val)
-{
-	struct i2c_client *client = v4l2_get_subdevdata(&ov9282->sd);
-	struct i2c_msg msgs[2] = {0};
-	u8 addr_buf[2] = {0};
-	u8 data_buf[4] = {0};
-	int ret;
-
-	if (WARN_ON(len > 4))
-		return -EINVAL;
-
-	put_unaligned_be16(reg, addr_buf);
-
-	/* Write register address */
-	msgs[0].addr = client->addr;
-	msgs[0].flags = 0;
-	msgs[0].len = ARRAY_SIZE(addr_buf);
-	msgs[0].buf = addr_buf;
-
-	/* Read data from register */
-	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;
-}
-
-/**
- * ov9282_write_reg() - Write register
- * @ov9282: pointer to ov9282 device
- * @reg: register address
- * @len: length of bytes. Max supported bytes is 4
- * @val: register value
- *
- * Return: 0 if successful, error code otherwise.
- */
-static int ov9282_write_reg(struct ov9282 *ov9282, u16 reg, u32 len, u32 val)
-{
-	struct i2c_client *client = v4l2_get_subdevdata(&ov9282->sd);
-	u8 buf[6] = {0};
-
-	if (WARN_ON(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;
-}
-
-/**
- * ov9282_write_regs() - Write a list of registers
- * @ov9282: pointer to ov9282 device
- * @regs: list of registers to be written
- * @len: length of registers array
- *
- * Return: 0 if successful, error code otherwise.
- */
-static int ov9282_write_regs(struct ov9282 *ov9282,
-			     const struct ov9282_reg *regs, u32 len)
-{
-	unsigned int i;
-	int ret;
-
-	for (i = 0; i < len; i++) {
-		ret = ov9282_write_reg(ov9282, regs[i].address, 1, regs[i].val);
-		if (ret)
-			return ret;
-	}
-
-	return 0;
-}
-
 /**
  * ov9282_update_controls() - Update control ranges based on streaming mode
  * @ov9282: pointer to ov9282 device
@@ -639,15 +536,15 @@ static int ov9282_update_exp_gain(struct ov9282 *ov9282, u32 exposure, u32 gain)
 	dev_dbg(ov9282->dev, "Set exp %u (~%u us), analog gain %u",
 		exposure, exposure_us, gain);
 
-	ret = ov9282_write_reg(ov9282, OV9282_REG_HOLD, 1, 1);
+	ret = cci_write(ov9282->regmap, OV9282_REG_HOLD, 0x01, NULL);
 	if (ret)
 		return ret;
 
-	ret = ov9282_write_reg(ov9282, OV9282_REG_EXPOSURE, 3, exposure << 4);
+	ret = cci_write(ov9282->regmap, OV9282_REG_EXPOSURE, exposure << 4, NULL);
 	if (ret)
 		goto error_release_group_hold;
 
-	ret = ov9282_write_reg(ov9282, OV9282_REG_AGAIN, 1, gain);
+	ret = cci_write(ov9282->regmap, OV9282_REG_AGAIN, gain, NULL);
 	if (ret)
 		goto error_release_group_hold;
 
@@ -656,62 +553,11 @@ static int ov9282_update_exp_gain(struct ov9282 *ov9282, u32 exposure, u32 gain)
 				       OV9282_STROBE_FRAME_SPAN_DEFAULT);
 
 error_release_group_hold:
-	ov9282_write_reg(ov9282, OV9282_REG_HOLD, 1, 0);
+	cci_write(ov9282->regmap, OV9282_REG_HOLD, 0, NULL);
 
 	return ret;
 }
 
-static int ov9282_set_ctrl_hflip(struct ov9282 *ov9282, int value)
-{
-	u32 current_val;
-	int ret = ov9282_read_reg(ov9282, OV9282_REG_TIMING_FORMAT_2, 1,
-				  &current_val);
-	if (ret)
-		return ret;
-
-	if (value)
-		current_val |= OV9282_FLIP_BIT;
-	else
-		current_val &= ~OV9282_FLIP_BIT;
-
-	return ov9282_write_reg(ov9282, OV9282_REG_TIMING_FORMAT_2, 1,
-				current_val);
-}
-
-static int ov9282_set_ctrl_vflip(struct ov9282 *ov9282, int value)
-{
-	u32 current_val;
-	int ret = ov9282_read_reg(ov9282, OV9282_REG_TIMING_FORMAT_1, 1,
-				  &current_val);
-	if (ret)
-		return ret;
-
-	if (value)
-		current_val |= OV9282_FLIP_BIT;
-	else
-		current_val &= ~OV9282_FLIP_BIT;
-
-	return ov9282_write_reg(ov9282, OV9282_REG_TIMING_FORMAT_1, 1,
-				current_val);
-}
-
-static int ov9282_set_ctrl_flash_strobe_oe(struct ov9282 *ov9282, bool enable)
-{
-	u32 current_val;
-	int ret;
-
-	ret = ov9282_read_reg(ov9282, OV9282_REG_OUTPUT_ENABLE6, 1, &current_val);
-	if (ret)
-		return ret;
-
-	if (enable)
-		current_val |= OV9282_OUTPUT_ENABLE6_STROBE;
-	else
-		current_val &= ~OV9282_OUTPUT_ENABLE6_STROBE;
-
-	return ov9282_write_reg(ov9282, OV9282_REG_OUTPUT_ENABLE6, 1, current_val);
-}
-
 static u32 ov9282_us_to_flash_duration(struct ov9282 *ov9282, u32 value)
 {
 	/*
@@ -740,30 +586,6 @@ static u32 ov9282_flash_duration_to_us(struct ov9282 *ov9282, u32 value)
 	return DIV_ROUND_UP(value * frame_width, OV9282_STROBE_SPAN_FACTOR);
 }
 
-static int ov9282_set_ctrl_flash_duration(struct ov9282 *ov9282, u32 value)
-{
-	u32 val = ov9282_us_to_flash_duration(ov9282, value);
-	int ret;
-
-	ret = ov9282_write_reg(ov9282, OV9282_REG_STROBE_FRAME_SPAN, 1,
-			       (val >> 24) & 0xff);
-	if (ret)
-		return ret;
-
-	ret = ov9282_write_reg(ov9282, OV9282_REG_STROBE_FRAME_SPAN + 1, 1,
-			       (val >> 16) & 0xff);
-	if (ret)
-		return ret;
-
-	ret = ov9282_write_reg(ov9282, OV9282_REG_STROBE_FRAME_SPAN + 2, 1,
-			       (val >> 8) & 0xff);
-	if (ret)
-		return ret;
-
-	return ov9282_write_reg(ov9282, OV9282_REG_STROBE_FRAME_SPAN + 3, 1,
-				val & 0xff);
-}
-
 /**
  * ov9282_set_ctrl() - Set subdevice control
  * @ctrl: pointer to v4l2_ctrl structure
@@ -818,23 +640,27 @@ static int ov9282_set_ctrl(struct v4l2_ctrl *ctrl)
 		break;
 	case V4L2_CID_VBLANK:
 		lpfr = ov9282->vblank + ov9282->cur_mode->height;
-		ret = ov9282_write_reg(ov9282, OV9282_REG_LPFR, 2, lpfr);
+		ret = cci_write(ov9282->regmap, OV9282_REG_LPFR, lpfr, NULL);
 		break;
 	case V4L2_CID_HFLIP:
-		ret = ov9282_set_ctrl_hflip(ov9282, ctrl->val);
+		ret = cci_update_bits(ov9282->regmap, OV9282_REG_TIMING_FORMAT_2,
+				      OV9282_FLIP_BIT, ctrl->val ? OV9282_FLIP_BIT : 0, NULL);
 		break;
 	case V4L2_CID_VFLIP:
-		ret = ov9282_set_ctrl_vflip(ov9282, ctrl->val);
+		ret = cci_update_bits(ov9282->regmap, OV9282_REG_TIMING_FORMAT_1,
+				      OV9282_FLIP_BIT, ctrl->val ? OV9282_FLIP_BIT : 0, NULL);
 		break;
 	case V4L2_CID_HBLANK:
-		ret = ov9282_write_reg(ov9282, OV9282_REG_TIMING_HTS, 2,
-				       (ctrl->val + ov9282->cur_mode->width) >> 1);
+		ret = cci_write(ov9282->regmap, OV9282_REG_TIMING_HTS,
+				(ctrl->val + ov9282->cur_mode->width) >> 1, NULL);
 		break;
 	case V4L2_CID_FLASH_STROBE_OE:
-		ret = ov9282_set_ctrl_flash_strobe_oe(ov9282, ctrl->val);
+		ret = cci_update_bits(ov9282->regmap, OV9282_REG_OUTPUT_ENABLE6,
+				      OV9282_OUTPUT_ENABLE6_STROBE,
+				      ctrl->val ? OV9282_OUTPUT_ENABLE6_STROBE : 0, NULL);
 		break;
 	case V4L2_CID_FLASH_DURATION:
-		ret = ov9282_set_ctrl_flash_duration(ov9282, ctrl->val);
+		ret = cci_write(ov9282->regmap, OV9282_REG_STROBE_FRAME_SPAN, ctrl->val, NULL);
 		break;
 	default:
 		dev_err(ov9282->dev, "Invalid control %d", ctrl->id);
@@ -1114,7 +940,7 @@ static int ov9282_get_selection(struct v4l2_subdev *sd,
  */
 static int ov9282_start_streaming(struct ov9282 *ov9282)
 {
-	const struct ov9282_reg bitdepth_regs[2][2] = {
+	const struct reg_sequence bitdepth_regs[2][2] = {
 		{
 			{OV9282_REG_PLL_CTRL_0D, OV9282_PLL_CTRL_0D_RAW10},
 			{OV9282_REG_ANA_CORE_2, OV9282_ANA_CORE2_RAW10},
@@ -1128,15 +954,16 @@ static int ov9282_start_streaming(struct ov9282 *ov9282)
 	int ret;
 
 	/* Write common registers */
-	ret = ov9282_write_regs(ov9282, common_regs_list.regs,
-				common_regs_list.num_of_regs);
+	ret = regmap_multi_reg_write(ov9282->regmap, common_regs,
+					ARRAY_SIZE(common_regs));
 	if (ret) {
 		dev_err(ov9282->dev, "fail to write common registers");
 		return ret;
 	}
 
 	bitdepth_index = ov9282->code == MEDIA_BUS_FMT_Y10_1X10 ? 0 : 1;
-	ret = ov9282_write_regs(ov9282, bitdepth_regs[bitdepth_index], 2);
+	ret = regmap_multi_reg_write(ov9282->regmap,
+				     bitdepth_regs[bitdepth_index], 2);
 	if (ret) {
 		dev_err(ov9282->dev, "fail to write bitdepth regs");
 		return ret;
@@ -1144,7 +971,8 @@ static int ov9282_start_streaming(struct ov9282 *ov9282)
 
 	/* Write sensor mode registers */
 	reg_list = &ov9282->cur_mode->reg_list;
-	ret = ov9282_write_regs(ov9282, reg_list->regs, reg_list->num_of_regs);
+	ret = regmap_multi_reg_write(ov9282->regmap, reg_list->regs,
+				     reg_list->num_of_regs);
 	if (ret) {
 		dev_err(ov9282->dev, "fail to write initial registers");
 		return ret;
@@ -1158,8 +986,8 @@ static int ov9282_start_streaming(struct ov9282 *ov9282)
 	}
 
 	/* Start streaming */
-	ret = ov9282_write_reg(ov9282, OV9282_REG_MODE_SELECT,
-			       1, OV9282_MODE_STREAMING);
+	ret = cci_write(ov9282->regmap, OV9282_REG_MODE_SELECT,
+			OV9282_MODE_STREAMING, NULL);
 	if (ret) {
 		dev_err(ov9282->dev, "fail to start streaming");
 		return ret;
@@ -1176,8 +1004,8 @@ static int ov9282_start_streaming(struct ov9282 *ov9282)
  */
 static int ov9282_stop_streaming(struct ov9282 *ov9282)
 {
-	return ov9282_write_reg(ov9282, OV9282_REG_MODE_SELECT,
-				1, OV9282_MODE_STANDBY);
+	return cci_write(ov9282->regmap, OV9282_REG_MODE_SELECT,
+			 OV9282_MODE_STANDBY, NULL);
 }
 
 /**
@@ -1228,14 +1056,14 @@ static int ov9282_set_stream(struct v4l2_subdev *sd, int enable)
 static int ov9282_detect(struct ov9282 *ov9282)
 {
 	int ret;
-	u32 val;
+	u64 val;
 
-	ret = ov9282_read_reg(ov9282, OV9282_REG_ID, 2, &val);
+	ret = cci_read(ov9282->regmap, OV9282_REG_ID, &val, NULL);
 	if (ret)
 		return ret;
 
 	if (val != OV9282_ID) {
-		dev_err(ov9282->dev, "chip id mismatch: %x!=%x",
+		dev_err(ov9282->dev, "chip id mismatch: %x!=%llx",
 			OV9282_ID, val);
 		return -ENXIO;
 	}
@@ -1397,9 +1225,8 @@ static int ov9282_power_on(struct device *dev)
 
 	usleep_range(400, 600);
 
-	ret = ov9282_write_reg(ov9282, OV9282_REG_MIPI_CTRL00, 1,
-			       ov9282->noncontinuous_clock ?
-					OV9282_GATED_CLOCK : 0);
+	ret = cci_write(ov9282->regmap, OV9282_REG_MIPI_CTRL00,
+			ov9282->noncontinuous_clock ? OV9282_GATED_CLOCK : 0, NULL);
 	if (ret) {
 		dev_err(ov9282->dev, "fail to write MIPI_CTRL00");
 		goto error_clk;
@@ -1576,6 +1403,11 @@ static int ov9282_probe(struct i2c_client *client)
 		return ret;
 	}
 
+	ov9282->regmap = devm_cci_regmap_init_i2c(client, 16);
+	if (IS_ERR(ov9282->regmap))
+		return dev_err_probe(ov9282->dev, PTR_ERR(ov9282->regmap),
+				     "Failed to init CCI\n");
+
 	mutex_init(&ov9282->mutex);
 
 	ret = ov9282_power_on(ov9282->dev);
-- 
2.43.0

[PATCH 2/3] media: i2c: ov9282: Switch to using the sub-device state lock

[Xiaolei Wang]

Switch to using the sub-device state lock and properly call
v4l2_subdev_init_finalize() / v4l2_subdev_cleanup() on probe() /
remove().

Signed-off-by: Xiaolei Wang <xiaolei.wang@windriver.com>
---
 drivers/media/i2c/ov9282.c | 48 ++++++++++++++------------------------
 1 file changed, 17 insertions(+), 31 deletions(-)

diff --git a/drivers/media/i2c/ov9282.c b/drivers/media/i2c/ov9282.c
index 75e41a0f588e..aa5a105136bf 100644
--- a/drivers/media/i2c/ov9282.c
+++ b/drivers/media/i2c/ov9282.c
@@ -220,7 +220,6 @@ struct ov9282 {
 	bool noncontinuous_clock;
 	const struct ov9282_mode *cur_mode;
 	u32 code;
-	struct mutex mutex;
 };
 
 static const s64 link_freq[] = {
@@ -794,8 +793,6 @@ static int ov9282_get_pad_format(struct v4l2_subdev *sd,
 {
 	struct ov9282 *ov9282 = to_ov9282(sd);
 
-	mutex_lock(&ov9282->mutex);
-
 	if (fmt->which == V4L2_SUBDEV_FORMAT_TRY) {
 		struct v4l2_mbus_framefmt *framefmt;
 
@@ -806,8 +803,6 @@ static int ov9282_get_pad_format(struct v4l2_subdev *sd,
 				       fmt);
 	}
 
-	mutex_unlock(&ov9282->mutex);
-
 	return 0;
 }
 
@@ -828,8 +823,6 @@ static int ov9282_set_pad_format(struct v4l2_subdev *sd,
 	u32 code;
 	int ret = 0;
 
-	mutex_lock(&ov9282->mutex);
-
 	mode = v4l2_find_nearest_size(supported_modes,
 				      ARRAY_SIZE(supported_modes),
 				      width, height,
@@ -855,8 +848,6 @@ static int ov9282_set_pad_format(struct v4l2_subdev *sd,
 		}
 	}
 
-	mutex_unlock(&ov9282->mutex);
-
 	return ret;
 }
 
@@ -903,10 +894,8 @@ static int ov9282_get_selection(struct v4l2_subdev *sd,
 	case V4L2_SEL_TGT_CROP: {
 		struct ov9282 *ov9282 = to_ov9282(sd);
 
-		mutex_lock(&ov9282->mutex);
 		sel->r = *__ov9282_get_pad_crop(ov9282, sd_state, sel->pad,
 						sel->which);
-		mutex_unlock(&ov9282->mutex);
 
 		return 0;
 	}
@@ -1018,9 +1007,10 @@ static int ov9282_stop_streaming(struct ov9282 *ov9282)
 static int ov9282_set_stream(struct v4l2_subdev *sd, int enable)
 {
 	struct ov9282 *ov9282 = to_ov9282(sd);
+	struct v4l2_subdev_state *state;
 	int ret;
 
-	mutex_lock(&ov9282->mutex);
+	state = v4l2_subdev_lock_and_get_active_state(sd);
 
 	if (enable) {
 		ret = pm_runtime_resume_and_get(ov9282->dev);
@@ -1035,14 +1025,14 @@ static int ov9282_set_stream(struct v4l2_subdev *sd, int enable)
 		pm_runtime_put(ov9282->dev);
 	}
 
-	mutex_unlock(&ov9282->mutex);
+	v4l2_subdev_unlock_state(state);
 
 	return 0;
 
 error_power_off:
 	pm_runtime_put(ov9282->dev);
 error_unlock:
-	mutex_unlock(&ov9282->mutex);
+	v4l2_subdev_unlock_state(state);
 
 	return ret;
 }
@@ -1284,9 +1274,6 @@ static int ov9282_init_controls(struct ov9282 *ov9282)
 	if (ret)
 		return ret;
 
-	/* Serialize controls with sensor device */
-	ctrl_hdlr->lock = &ov9282->mutex;
-
 	/* Initialize exposure and gain */
 	lpfr = mode->vblank + mode->height;
 	ov9282->exp_ctrl = v4l2_ctrl_new_std(ctrl_hdlr,
@@ -1408,13 +1395,10 @@ static int ov9282_probe(struct i2c_client *client)
 		return dev_err_probe(ov9282->dev, PTR_ERR(ov9282->regmap),
 				     "Failed to init CCI\n");
 
-	mutex_init(&ov9282->mutex);
-
 	ret = ov9282_power_on(ov9282->dev);
-	if (ret) {
-		dev_err(ov9282->dev, "failed to power-on the sensor");
-		goto error_mutex_destroy;
-	}
+	if (ret)
+		return dev_err_probe(ov9282->dev, ret,
+				     "failed to power-on the sensor");
 
 	/* Check module identity */
 	ret = ov9282_detect(ov9282);
@@ -1447,10 +1431,10 @@ static int ov9282_probe(struct i2c_client *client)
 		goto error_handler_free;
 	}
 
-	ret = v4l2_async_register_subdev_sensor(&ov9282->sd);
+	ov9282->sd.state_lock = ov9282->ctrl_handler.lock;
+	ret = v4l2_subdev_init_finalize(&ov9282->sd);
 	if (ret < 0) {
-		dev_err(ov9282->dev,
-			"failed to register async subdev: %d", ret);
+		ret = dev_err_probe(ov9282->dev, ret, "failed to init subdev\n");
 		goto error_media_entity;
 	}
 
@@ -1458,16 +1442,20 @@ static int ov9282_probe(struct i2c_client *client)
 	pm_runtime_enable(ov9282->dev);
 	pm_runtime_idle(ov9282->dev);
 
+	ret = v4l2_async_register_subdev_sensor(&ov9282->sd);
+	if (ret < 0)
+		goto v4l2_subdev_cleanup;
+
 	return 0;
 
+v4l2_subdev_cleanup:
+	v4l2_subdev_cleanup(&ov9282->sd);
 error_media_entity:
 	media_entity_cleanup(&ov9282->sd.entity);
 error_handler_free:
 	v4l2_ctrl_handler_free(ov9282->sd.ctrl_handler);
 error_power_off:
 	ov9282_power_off(ov9282->dev);
-error_mutex_destroy:
-	mutex_destroy(&ov9282->mutex);
 
 	return ret;
 }
@@ -1481,9 +1469,9 @@ static int ov9282_probe(struct i2c_client *client)
 static void ov9282_remove(struct i2c_client *client)
 {
 	struct v4l2_subdev *sd = i2c_get_clientdata(client);
-	struct ov9282 *ov9282 = to_ov9282(sd);
 
 	v4l2_async_unregister_subdev(sd);
+	v4l2_subdev_cleanup(sd);
 	media_entity_cleanup(&sd->entity);
 	v4l2_ctrl_handler_free(sd->ctrl_handler);
 
@@ -1491,8 +1479,6 @@ static void ov9282_remove(struct i2c_client *client)
 	if (!pm_runtime_status_suspended(&client->dev))
 		ov9282_power_off(&client->dev);
 	pm_runtime_set_suspended(&client->dev);
-
-	mutex_destroy(&ov9282->mutex);
 }
 
 static const struct dev_pm_ops ov9282_pm_ops = {
-- 
2.43.0

[PATCH 3/3] media: i2c: ov9282: switch to {enable,disable}_streams

[Xiaolei Wang]

Switch from s_stream to enable_streams and disable_streams callbacks.

Signed-off-by: Xiaolei Wang <xiaolei.wang@windriver.com>
---
 drivers/media/i2c/ov9282.c | 82 ++++++++++++--------------------------
 1 file changed, 25 insertions(+), 57 deletions(-)

diff --git a/drivers/media/i2c/ov9282.c b/drivers/media/i2c/ov9282.c
index aa5a105136bf..b080a56d83a9 100644
--- a/drivers/media/i2c/ov9282.c
+++ b/drivers/media/i2c/ov9282.c
@@ -921,13 +921,9 @@ static int ov9282_get_selection(struct v4l2_subdev *sd,
 	return -EINVAL;
 }
 
-/**
- * ov9282_start_streaming() - Start sensor stream
- * @ov9282: pointer to ov9282 device
- *
- * Return: 0 if successful, error code otherwise.
- */
-static int ov9282_start_streaming(struct ov9282 *ov9282)
+static int ov9282_enable_streams(struct v4l2_subdev *sd,
+				 struct v4l2_subdev_state *state, u32 pad,
+				 u64 streams_mask)
 {
 	const struct reg_sequence bitdepth_regs[2][2] = {
 		{
@@ -938,16 +934,21 @@ static int ov9282_start_streaming(struct ov9282 *ov9282)
 			{OV9282_REG_ANA_CORE_2, OV9282_ANA_CORE2_RAW8},
 		}
 	};
+	struct ov9282 *ov9282 = to_ov9282(sd);
 	const struct ov9282_reg_list *reg_list;
 	int bitdepth_index;
 	int ret;
 
+	ret = pm_runtime_resume_and_get(ov9282->dev);
+	if (ret)
+		return ret;
+
 	/* Write common registers */
 	ret = regmap_multi_reg_write(ov9282->regmap, common_regs,
 					ARRAY_SIZE(common_regs));
 	if (ret) {
 		dev_err(ov9282->dev, "fail to write common registers");
-		return ret;
+		goto done;
 	}
 
 	bitdepth_index = ov9282->code == MEDIA_BUS_FMT_Y10_1X10 ? 0 : 1;
@@ -955,7 +956,7 @@ static int ov9282_start_streaming(struct ov9282 *ov9282)
 				     bitdepth_regs[bitdepth_index], 2);
 	if (ret) {
 		dev_err(ov9282->dev, "fail to write bitdepth regs");
-		return ret;
+		goto done;
 	}
 
 	/* Write sensor mode registers */
@@ -964,75 +965,40 @@ static int ov9282_start_streaming(struct ov9282 *ov9282)
 				     reg_list->num_of_regs);
 	if (ret) {
 		dev_err(ov9282->dev, "fail to write initial registers");
-		return ret;
+		goto done;
 	}
 
 	/* Setup handler will write actual exposure and gain */
 	ret =  __v4l2_ctrl_handler_setup(ov9282->sd.ctrl_handler);
 	if (ret) {
 		dev_err(ov9282->dev, "fail to setup handler");
-		return ret;
+		goto done;
 	}
 
 	/* Start streaming */
 	ret = cci_write(ov9282->regmap, OV9282_REG_MODE_SELECT,
 			OV9282_MODE_STREAMING, NULL);
-	if (ret) {
+	if (ret)
 		dev_err(ov9282->dev, "fail to start streaming");
-		return ret;
-	}
 
-	return 0;
-}
+done:
+	if (ret)
+		pm_runtime_put(ov9282->dev);
 
-/**
- * ov9282_stop_streaming() - Stop sensor stream
- * @ov9282: pointer to ov9282 device
- *
- * Return: 0 if successful, error code otherwise.
- */
-static int ov9282_stop_streaming(struct ov9282 *ov9282)
-{
-	return cci_write(ov9282->regmap, OV9282_REG_MODE_SELECT,
-			 OV9282_MODE_STANDBY, NULL);
+	return ret;
 }
 
-/**
- * ov9282_set_stream() - Enable sensor streaming
- * @sd: pointer to ov9282 subdevice
- * @enable: set to enable sensor streaming
- *
- * Return: 0 if successful, error code otherwise.
- */
-static int ov9282_set_stream(struct v4l2_subdev *sd, int enable)
+static int ov9282_disable_streams(struct v4l2_subdev *sd,
+				  struct v4l2_subdev_state *state, u32 pad,
+				  u64 streams_mask)
 {
 	struct ov9282 *ov9282 = to_ov9282(sd);
-	struct v4l2_subdev_state *state;
 	int ret;
 
-	state = v4l2_subdev_lock_and_get_active_state(sd);
-
-	if (enable) {
-		ret = pm_runtime_resume_and_get(ov9282->dev);
-		if (ret)
-			goto error_unlock;
-
-		ret = ov9282_start_streaming(ov9282);
-		if (ret)
-			goto error_power_off;
-	} else {
-		ov9282_stop_streaming(ov9282);
-		pm_runtime_put(ov9282->dev);
-	}
-
-	v4l2_subdev_unlock_state(state);
-
-	return 0;
+	ret = cci_write(ov9282->regmap, OV9282_REG_MODE_SELECT,
+			 OV9282_MODE_STANDBY, NULL);
 
-error_power_off:
 	pm_runtime_put(ov9282->dev);
-error_unlock:
-	v4l2_subdev_unlock_state(state);
 
 	return ret;
 }
@@ -1164,7 +1130,7 @@ static const struct v4l2_subdev_core_ops ov9282_core_ops = {
 };
 
 static const struct v4l2_subdev_video_ops ov9282_video_ops = {
-	.s_stream = ov9282_set_stream,
+	.s_stream = v4l2_subdev_s_stream_helper,
 };
 
 static const struct v4l2_subdev_pad_ops ov9282_pad_ops = {
@@ -1173,6 +1139,8 @@ static const struct v4l2_subdev_pad_ops ov9282_pad_ops = {
 	.get_fmt = ov9282_get_pad_format,
 	.set_fmt = ov9282_set_pad_format,
 	.get_selection = ov9282_get_selection,
+	.enable_streams = ov9282_enable_streams,
+	.disable_streams = ov9282_disable_streams,
 };
 
 static const struct v4l2_subdev_ops ov9282_subdev_ops = {
-- 
2.43.0

Re: [PATCH 1/3] media: i2c: ov9282: Convert to CCI register access helpers

[Tarang Raval]

Hi Xiaolei,

> Use the new common CCI register access helpers to replace the private
> register access helpers in the ov9282 driver. This simplifies the driver
> by reducing the amount of code.
>
> Signed-off-by: Xiaolei Wang <xiaolei.wang@windriver.com>

...

>  /**
>   * ov9282_update_controls() - Update control ranges based on streaming mode
>   * @ov9282: pointer to ov9282 device
> @@ -639,15 +536,15 @@ static int ov9282_update_exp_gain(struct ov9282 *ov9282, u32 exposure, u32 gain)
>         dev_dbg(ov9282->dev, "Set exp %u (~%u us), analog gain %u",
>                 exposure, exposure_us, gain);
>
> -       ret = ov9282_write_reg(ov9282, OV9282_REG_HOLD, 1, 1);
> +       ret = cci_write(ov9282->regmap, OV9282_REG_HOLD, 0x01, NULL);
>         if (ret)
>                 return ret;
>
> -       ret = ov9282_write_reg(ov9282, OV9282_REG_EXPOSURE, 3, exposure << 4);
> +       ret = cci_write(ov9282->regmap, OV9282_REG_EXPOSURE, exposure << 4, NULL);
>         if (ret)
>                 goto error_release_group_hold;
>
> -       ret = ov9282_write_reg(ov9282, OV9282_REG_AGAIN, 1, gain);
> +       ret = cci_write(ov9282->regmap, OV9282_REG_AGAIN, gain, NULL);
>         if (ret)
>                 goto error_release_group_hold;
>
> @@ -656,62 +553,11 @@ static int ov9282_update_exp_gain(struct ov9282 *ov9282, u32 exposure, u32 gain)
>                                        OV9282_STROBE_FRAME_SPAN_DEFAULT);
>
>  error_release_group_hold:
> -       ov9282_write_reg(ov9282, OV9282_REG_HOLD, 1, 0);
> +       cci_write(ov9282->regmap, OV9282_REG_HOLD, 0, NULL);

If all the operations above succeed but releasing the group hold fails,
you still return success, which is wrong.

This case is rare, but it’s better to fix the error path.

I think we should do something like this:

error_release_group_hold:
      int ret_hold = cci_write(ov9282->regmap, OV9282_REG_HOLD, 0, NULL);

      return ret ? ret : ret_hold;

>
>         return ret;
>  }

Other than this issue, the patch looks good to me.

Reviewed-by: Tarang Raval <tarang.raval@siliconsignals.io>

Best Regards,
Tarang

Re: [PATCH 2/3] media: i2c: ov9282: Switch to using the sub-device state lock

[Tarang Raval]

Hi Xiaolei,

> Switch to using the sub-device state lock and properly call
> v4l2_subdev_init_finalize() / v4l2_subdev_cleanup() on probe() /
> remove().
>
> Signed-off-by: Xiaolei Wang <xiaolei.wang@windriver.com>

...

>
> @@ -1458,16 +1442,20 @@ static int ov9282_probe(struct i2c_client *client)
>         pm_runtime_enable(ov9282->dev);
>         pm_runtime_idle(ov9282->dev);
>
> +       ret = v4l2_async_register_subdev_sensor(&ov9282->sd);
> +       if (ret < 0)
> +               goto v4l2_subdev_cleanup;
> +
>         return 0;
>
> +v4l2_subdev_cleanup:
> +       v4l2_subdev_cleanup(&ov9282->sd);


If v4l2_async_register_subdev_sensor() fails, runtime PM remains enabled.
Can you please disable runtime PM (and set suspended state) on that error path?


>  error_media_entity:
>         media_entity_cleanup(&ov9282->sd.entity);
>  error_handler_free:
>         v4l2_ctrl_handler_free(ov9282->sd.ctrl_handler);
>  error_power_off:
>         ov9282_power_off(ov9282->dev);
> -error_mutex_destroy:
> -       mutex_destroy(&ov9282->mutex);
>
>         return ret;
>  }
> @@ -1481,9 +1469,9 @@ static int ov9282_probe(struct i2c_client *client)
>  static void ov9282_remove(struct i2c_client *client)
>  {
>         struct v4l2_subdev *sd = i2c_get_clientdata(client);
> -       struct ov9282 *ov9282 = to_ov9282(sd);
>
>         v4l2_async_unregister_subdev(sd);
> +       v4l2_subdev_cleanup(sd);
>         media_entity_cleanup(&sd->entity);
>         v4l2_ctrl_handler_free(sd->ctrl_handler);
>
> @@ -1491,8 +1479,6 @@ static void ov9282_remove(struct i2c_client *client)
>         if (!pm_runtime_status_suspended(&client->dev))
>                 ov9282_power_off(&client->dev);
>         pm_runtime_set_suspended(&client->dev);
> -
> -       mutex_destroy(&ov9282->mutex);
>  }
>
>  static const struct dev_pm_ops ov9282_pm_ops = {
> --
> 2.43.0

with above change

Reviewed-by: Tarang Raval <tarang.raval@siliconsignals.io>

Best Regards,
Tarang

Re: [PATCH 3/3] media: i2c: ov9282: switch to {enable,disable}_streams

[Tarang Raval]

Hi Xiaolei,

> Switch from s_stream to enable_streams and disable_streams callbacks.
>
> Signed-off-by: Xiaolei Wang <xiaolei.wang@windriver.com>
> ---
>  drivers/media/i2c/ov9282.c | 82 ++++++++++++--------------------------
>  1 file changed, 25 insertions(+), 57 deletions(-)
>
> diff --git a/drivers/media/i2c/ov9282.c b/drivers/media/i2c/ov9282.c
> index aa5a105136bf..b080a56d83a9 100644
> --- a/drivers/media/i2c/ov9282.c
> +++ b/drivers/media/i2c/ov9282.c
> @@ -921,13 +921,9 @@ static int ov9282_get_selection(struct v4l2_subdev *sd,
>         return -EINVAL;
>  }
>
> -/**
> - * ov9282_start_streaming() - Start sensor stream
> - * @ov9282: pointer to ov9282 device
> - *
> - * Return: 0 if successful, error code otherwise.
> - */
> -static int ov9282_start_streaming(struct ov9282 *ov9282)
> +static int ov9282_enable_streams(struct v4l2_subdev *sd,
> +                                struct v4l2_subdev_state *state, u32 pad,
> +                                u64 streams_mask)
>  {
>         const struct reg_sequence bitdepth_regs[2][2] = {
>                 {
> @@ -938,16 +934,21 @@ static int ov9282_start_streaming(struct ov9282 *ov9282)
>                         {OV9282_REG_ANA_CORE_2, OV9282_ANA_CORE2_RAW8},
>                 }
>         };
> +       struct ov9282 *ov9282 = to_ov9282(sd);
>         const struct ov9282_reg_list *reg_list;
>         int bitdepth_index;
>         int ret;
>
> +       ret = pm_runtime_resume_and_get(ov9282->dev);
> +       if (ret)
> +               return ret;
> +
>         /* Write common registers */
>         ret = regmap_multi_reg_write(ov9282->regmap, common_regs,
>                                         ARRAY_SIZE(common_regs));
>         if (ret) {
>                 dev_err(ov9282->dev, "fail to write common registers");
> -               return ret;
> +               goto done;
>         }
>
>         bitdepth_index = ov9282->code == MEDIA_BUS_FMT_Y10_1X10 ? 0 : 1;
> @@ -955,7 +956,7 @@ static int ov9282_start_streaming(struct ov9282 *ov9282)
>                                      bitdepth_regs[bitdepth_index], 2);
>         if (ret) {
>                 dev_err(ov9282->dev, "fail to write bitdepth regs");
> -               return ret;
> +               goto done;
>         }
>
>         /* Write sensor mode registers */
> @@ -964,75 +965,40 @@ static int ov9282_start_streaming(struct ov9282 *ov9282)
>                                      reg_list->num_of_regs);
>         if (ret) {
>                 dev_err(ov9282->dev, "fail to write initial registers");
> -               return ret;
> +               goto done;
>         }
>
>         /* Setup handler will write actual exposure and gain */
>         ret =  __v4l2_ctrl_handler_setup(ov9282->sd.ctrl_handler);
>         if (ret) {
>                 dev_err(ov9282->dev, "fail to setup handler");
> -               return ret;
> +               goto done;
>         }
>
>         /* Start streaming */
>         ret = cci_write(ov9282->regmap, OV9282_REG_MODE_SELECT,
>                         OV9282_MODE_STREAMING, NULL);
> -       if (ret) {
> +       if (ret)
>                 dev_err(ov9282->dev, "fail to start streaming");
> -               return ret;
> -       }
>
> -       return 0;
> -}
> +done:
> +       if (ret)
> +               pm_runtime_put(ov9282->dev);


The current flow looks odd; can we use a conventional error path with a clear
label like err_pm_put:

      /* Start streaming */
      ret = cci_write(ov9282->regmap, OV9282_REG_MODE_SELECT,
                      OV9282_MODE_STREAMING, NULL);
      if (ret)
              dev_err(ov9282->dev, "fail to start streaming");
              goto err_pm_put;
      }

      return 0;

err_pm_put:
      pm_runtime_put(ov9282->dev);
      return ret;

>
> -/**
> - * ov9282_stop_streaming() - Stop sensor stream
> - * @ov9282: pointer to ov9282 device
> - *
> - * Return: 0 if successful, error code otherwise.
> - */
> -static int ov9282_stop_streaming(struct ov9282 *ov9282)
> -{
> -       return cci_write(ov9282->regmap, OV9282_REG_MODE_SELECT,
> -                        OV9282_MODE_STANDBY, NULL);
> +       return ret;
>  }
>
> -/**
> - * ov9282_set_stream() - Enable sensor streaming
> - * @sd: pointer to ov9282 subdevice
> - * @enable: set to enable sensor streaming
> - *
> - * Return: 0 if successful, error code otherwise.
> - */
> -static int ov9282_set_stream(struct v4l2_subdev *sd, int enable)
> +static int ov9282_disable_streams(struct v4l2_subdev *sd,
> +                                 struct v4l2_subdev_state *state, u32 pad,
> +                                 u64 streams_mask)
>  {
>         struct ov9282 *ov9282 = to_ov9282(sd);
> -       struct v4l2_subdev_state *state;
>         int ret;
>
> -       state = v4l2_subdev_lock_and_get_active_state(sd);
> -
> -       if (enable) {
> -               ret = pm_runtime_resume_and_get(ov9282->dev);
> -               if (ret)
> -                       goto error_unlock;
> -
> -               ret = ov9282_start_streaming(ov9282);
> -               if (ret)
> -                       goto error_power_off;
> -       } else {
> -               ov9282_stop_streaming(ov9282);
> -               pm_runtime_put(ov9282->dev);
> -       }
> -
> -       v4l2_subdev_unlock_state(state);
> -
> -       return 0;
> +       ret = cci_write(ov9282->regmap, OV9282_REG_MODE_SELECT,
> +                        OV9282_MODE_STANDBY, NULL);
>
> -error_power_off:
>         pm_runtime_put(ov9282->dev);
> -error_unlock:
> -       v4l2_subdev_unlock_state(state);
>
>         return ret;
>  }
> @@ -1164,7 +1130,7 @@ static const struct v4l2_subdev_core_ops ov9282_core_ops = {
>  };
>
>  static const struct v4l2_subdev_video_ops ov9282_video_ops = {
> -       .s_stream = ov9282_set_stream,
> +       .s_stream = v4l2_subdev_s_stream_helper,
>  };
>
>  static const struct v4l2_subdev_pad_ops ov9282_pad_ops = {
> @@ -1173,6 +1139,8 @@ static const struct v4l2_subdev_pad_ops ov9282_pad_ops = {
>         .get_fmt = ov9282_get_pad_format,
>         .set_fmt = ov9282_set_pad_format,
>         .get_selection = ov9282_get_selection,
> +       .enable_streams = ov9282_enable_streams,
> +       .disable_streams = ov9282_disable_streams,
>  };
>
>  static const struct v4l2_subdev_ops ov9282_subdev_ops = {
> --
> 2.43.0

Reviewed-by: Tarang Raval <tarang.raval@siliconsignals.io>

Best Regards,
Tarang

Re: [PATCH 1/3] media: i2c: ov9282: Convert to CCI register access helpers

[xiaolei wang]

On 3/1/26 02:12, Tarang Raval wrote:
> CAUTION: This email comes from a non Wind River email account!
> Do not click links or open attachments unless you recognize the sender and know the content is safe.
>
> Hi Xiaolei,
>
>> Use the new common CCI register access helpers to replace the private
>> register access helpers in the ov9282 driver. This simplifies the driver
>> by reducing the amount of code.
>>
>> Signed-off-by: Xiaolei Wang <xiaolei.wang@windriver.com>
> ...
>
>>   /**
>>    * ov9282_update_controls() - Update control ranges based on streaming mode
>>    * @ov9282: pointer to ov9282 device
>> @@ -639,15 +536,15 @@ static int ov9282_update_exp_gain(struct ov9282 *ov9282, u32 exposure, u32 gain)
>>          dev_dbg(ov9282->dev, "Set exp %u (~%u us), analog gain %u",
>>                  exposure, exposure_us, gain);
>>
>> -       ret = ov9282_write_reg(ov9282, OV9282_REG_HOLD, 1, 1);
>> +       ret = cci_write(ov9282->regmap, OV9282_REG_HOLD, 0x01, NULL);
>>          if (ret)
>>                  return ret;
>>
>> -       ret = ov9282_write_reg(ov9282, OV9282_REG_EXPOSURE, 3, exposure << 4);
>> +       ret = cci_write(ov9282->regmap, OV9282_REG_EXPOSURE, exposure << 4, NULL);
>>          if (ret)
>>                  goto error_release_group_hold;
>>
>> -       ret = ov9282_write_reg(ov9282, OV9282_REG_AGAIN, 1, gain);
>> +       ret = cci_write(ov9282->regmap, OV9282_REG_AGAIN, gain, NULL);
>>          if (ret)
>>                  goto error_release_group_hold;
>>
>> @@ -656,62 +553,11 @@ static int ov9282_update_exp_gain(struct ov9282 *ov9282, u32 exposure, u32 gain)
>>                                         OV9282_STROBE_FRAME_SPAN_DEFAULT);
>>
>>   error_release_group_hold:
>> -       ov9282_write_reg(ov9282, OV9282_REG_HOLD, 1, 0);
>> +       cci_write(ov9282->regmap, OV9282_REG_HOLD, 0, NULL);
> If all the operations above succeed but releasing the group hold fails,
> you still return success, which is wrong.
>
> This case is rare, but it’s better to fix the error path.
>
> I think we should do something like this:
>
> error_release_group_hold:
>       int ret_hold = cci_write(ov9282->regmap, OV9282_REG_HOLD, 0, NULL);
>
>       return ret ? ret : ret_hold;
Hi Tarang,

Thank you for catching this!

  I'll fix it in v2 with:

error_release_group_hold:
     int ret_hold = cci_write(ov9282->regmap, OV9282_REG_HOLD, 0, NULL);
     return ret ? ret : ret_hold;

Best Regards,
Xiaolei
>
>>          return ret;
>>   }
> Other than this issue, the patch looks good to me.
>
> Reviewed-by: Tarang Raval <tarang.raval@siliconsignals.io>
>
> Best Regards,
> Tarang

Re: [PATCH 2/3] media: i2c: ov9282: Switch to using the sub-device state lock

[xiaolei wang]

On 3/1/26 02:27, Tarang Raval wrote:
> CAUTION: This email comes from a non Wind River email account!
> Do not click links or open attachments unless you recognize the sender and know the content is safe.
>
> Hi Xiaolei,
>
>> Switch to using the sub-device state lock and properly call
>> v4l2_subdev_init_finalize() / v4l2_subdev_cleanup() on probe() /
>> remove().
>>
>> Signed-off-by: Xiaolei Wang <xiaolei.wang@windriver.com>
> ...
>
>> @@ -1458,16 +1442,20 @@ static int ov9282_probe(struct i2c_client *client)
>>          pm_runtime_enable(ov9282->dev);
>>          pm_runtime_idle(ov9282->dev);
>>
>> +       ret = v4l2_async_register_subdev_sensor(&ov9282->sd);
>> +       if (ret < 0)
>> +               goto v4l2_subdev_cleanup;
>> +
>>          return 0;
>>
>> +v4l2_subdev_cleanup:
>> +       v4l2_subdev_cleanup(&ov9282->sd);
>
> If v4l2_async_register_subdev_sensor() fails, runtime PM remains enabled.
> Can you please disable runtime PM (and set suspended state) on that error path?
Hi Tarang,

Thank you for the review!

You're right, I missed the runtime PM cleanup in the error path.
I'll fix it in v2:

v4l2_subdev_cleanup:
     v4l2_subdev_cleanup(&ov9282->sd);
     pm_runtime_disable(ov9282->dev);
     pm_runtime_set_suspended(ov9282->dev);
     goto error_media_entity;

This ensures runtime PM is properly disabled if subdev registration fails.

Best Regards,
Xiaolei
>
>
>>   error_media_entity:
>>          media_entity_cleanup(&ov9282->sd.entity);
>>   error_handler_free:
>>          v4l2_ctrl_handler_free(ov9282->sd.ctrl_handler);
>>   error_power_off:
>>          ov9282_power_off(ov9282->dev);
>> -error_mutex_destroy:
>> -       mutex_destroy(&ov9282->mutex);
>>
>>          return ret;
>>   }
>> @@ -1481,9 +1469,9 @@ static int ov9282_probe(struct i2c_client *client)
>>   static void ov9282_remove(struct i2c_client *client)
>>   {
>>          struct v4l2_subdev *sd = i2c_get_clientdata(client);
>> -       struct ov9282 *ov9282 = to_ov9282(sd);
>>
>>          v4l2_async_unregister_subdev(sd);
>> +       v4l2_subdev_cleanup(sd);
>>          media_entity_cleanup(&sd->entity);
>>          v4l2_ctrl_handler_free(sd->ctrl_handler);
>>
>> @@ -1491,8 +1479,6 @@ static void ov9282_remove(struct i2c_client *client)
>>          if (!pm_runtime_status_suspended(&client->dev))
>>                  ov9282_power_off(&client->dev);
>>          pm_runtime_set_suspended(&client->dev);
>> -
>> -       mutex_destroy(&ov9282->mutex);
>>   }
>>
>>   static const struct dev_pm_ops ov9282_pm_ops = {
>> --
>> 2.43.0
> with above change
>
> Reviewed-by: Tarang Raval <tarang.raval@siliconsignals.io>
>
> Best Regards,
> Tarang

Re: [PATCH 3/3] media: i2c: ov9282: switch to {enable,disable}_streams

[xiaolei wang]

On 3/1/26 02:45, Tarang Raval wrote:
> CAUTION: This email comes from a non Wind River email account!
> Do not click links or open attachments unless you recognize the sender and know the content is safe.
>
> Hi Xiaolei,
>
>> Switch from s_stream to enable_streams and disable_streams callbacks.
>>
>> Signed-off-by: Xiaolei Wang <xiaolei.wang@windriver.com>
>> ---
>>   drivers/media/i2c/ov9282.c | 82 ++++++++++++--------------------------
>>   1 file changed, 25 insertions(+), 57 deletions(-)
>>
>> diff --git a/drivers/media/i2c/ov9282.c b/drivers/media/i2c/ov9282.c
>> index aa5a105136bf..b080a56d83a9 100644
>> --- a/drivers/media/i2c/ov9282.c
>> +++ b/drivers/media/i2c/ov9282.c
>> @@ -921,13 +921,9 @@ static int ov9282_get_selection(struct v4l2_subdev *sd,
>>          return -EINVAL;
>>   }
>>
>> -/**
>> - * ov9282_start_streaming() - Start sensor stream
>> - * @ov9282: pointer to ov9282 device
>> - *
>> - * Return: 0 if successful, error code otherwise.
>> - */
>> -static int ov9282_start_streaming(struct ov9282 *ov9282)
>> +static int ov9282_enable_streams(struct v4l2_subdev *sd,
>> +                                struct v4l2_subdev_state *state, u32 pad,
>> +                                u64 streams_mask)
>>   {
>>          const struct reg_sequence bitdepth_regs[2][2] = {
>>                  {
>> @@ -938,16 +934,21 @@ static int ov9282_start_streaming(struct ov9282 *ov9282)
>>                          {OV9282_REG_ANA_CORE_2, OV9282_ANA_CORE2_RAW8},
>>                  }
>>          };
>> +       struct ov9282 *ov9282 = to_ov9282(sd);
>>          const struct ov9282_reg_list *reg_list;
>>          int bitdepth_index;
>>          int ret;
>>
>> +       ret = pm_runtime_resume_and_get(ov9282->dev);
>> +       if (ret)
>> +               return ret;
>> +
>>          /* Write common registers */
>>          ret = regmap_multi_reg_write(ov9282->regmap, common_regs,
>>                                          ARRAY_SIZE(common_regs));
>>          if (ret) {
>>                  dev_err(ov9282->dev, "fail to write common registers");
>> -               return ret;
>> +               goto done;
>>          }
>>
>>          bitdepth_index = ov9282->code == MEDIA_BUS_FMT_Y10_1X10 ? 0 : 1;
>> @@ -955,7 +956,7 @@ static int ov9282_start_streaming(struct ov9282 *ov9282)
>>                                       bitdepth_regs[bitdepth_index], 2);
>>          if (ret) {
>>                  dev_err(ov9282->dev, "fail to write bitdepth regs");
>> -               return ret;
>> +               goto done;
>>          }
>>
>>          /* Write sensor mode registers */
>> @@ -964,75 +965,40 @@ static int ov9282_start_streaming(struct ov9282 *ov9282)
>>                                       reg_list->num_of_regs);
>>          if (ret) {
>>                  dev_err(ov9282->dev, "fail to write initial registers");
>> -               return ret;
>> +               goto done;
>>          }
>>
>>          /* Setup handler will write actual exposure and gain */
>>          ret =  __v4l2_ctrl_handler_setup(ov9282->sd.ctrl_handler);
>>          if (ret) {
>>                  dev_err(ov9282->dev, "fail to setup handler");
>> -               return ret;
>> +               goto done;
>>          }
>>
>>          /* Start streaming */
>>          ret = cci_write(ov9282->regmap, OV9282_REG_MODE_SELECT,
>>                          OV9282_MODE_STREAMING, NULL);
>> -       if (ret) {
>> +       if (ret)
>>                  dev_err(ov9282->dev, "fail to start streaming");
>> -               return ret;
>> -       }
>>
>> -       return 0;
>> -}
>> +done:
>> +       if (ret)
>> +               pm_runtime_put(ov9282->dev);
>
> The current flow looks odd; can we use a conventional error path with a clear
> label like err_pm_put:
>
>       /* Start streaming */
>       ret = cci_write(ov9282->regmap, OV9282_REG_MODE_SELECT,
>                       OV9282_MODE_STREAMING, NULL);
>       if (ret)
>               dev_err(ov9282->dev, "fail to start streaming");
>               goto err_pm_put;
>       }
>
>       return 0;
>
> err_pm_put:
>       pm_runtime_put(ov9282->dev);
>       return ret;
Hi Tarang,

Thank you for the review!

I'll update it in v2:

/* Start streaming */
ret = cci_write(ov9282->regmap, OV9282_REG_MODE_SELECT,
                 OV9282_MODE_STREAMING, NULL);
if (ret) {
     dev_err(ov9282->dev, "fail to start streaming");
     goto err_pm_put;
}

return 0;

err_pm_put:
     pm_runtime_put(ov9282->dev);
     return ret;

Best Regards,
Xiaolei
>
>> -/**
>> - * ov9282_stop_streaming() - Stop sensor stream
>> - * @ov9282: pointer to ov9282 device
>> - *
>> - * Return: 0 if successful, error code otherwise.
>> - */
>> -static int ov9282_stop_streaming(struct ov9282 *ov9282)
>> -{
>> -       return cci_write(ov9282->regmap, OV9282_REG_MODE_SELECT,
>> -                        OV9282_MODE_STANDBY, NULL);
>> +       return ret;
>>   }
>>
>> -/**
>> - * ov9282_set_stream() - Enable sensor streaming
>> - * @sd: pointer to ov9282 subdevice
>> - * @enable: set to enable sensor streaming
>> - *
>> - * Return: 0 if successful, error code otherwise.
>> - */
>> -static int ov9282_set_stream(struct v4l2_subdev *sd, int enable)
>> +static int ov9282_disable_streams(struct v4l2_subdev *sd,
>> +                                 struct v4l2_subdev_state *state, u32 pad,
>> +                                 u64 streams_mask)
>>   {
>>          struct ov9282 *ov9282 = to_ov9282(sd);
>> -       struct v4l2_subdev_state *state;
>>          int ret;
>>
>> -       state = v4l2_subdev_lock_and_get_active_state(sd);
>> -
>> -       if (enable) {
>> -               ret = pm_runtime_resume_and_get(ov9282->dev);
>> -               if (ret)
>> -                       goto error_unlock;
>> -
>> -               ret = ov9282_start_streaming(ov9282);
>> -               if (ret)
>> -                       goto error_power_off;
>> -       } else {
>> -               ov9282_stop_streaming(ov9282);
>> -               pm_runtime_put(ov9282->dev);
>> -       }
>> -
>> -       v4l2_subdev_unlock_state(state);
>> -
>> -       return 0;
>> +       ret = cci_write(ov9282->regmap, OV9282_REG_MODE_SELECT,
>> +                        OV9282_MODE_STANDBY, NULL);
>>
>> -error_power_off:
>>          pm_runtime_put(ov9282->dev);
>> -error_unlock:
>> -       v4l2_subdev_unlock_state(state);
>>
>>          return ret;
>>   }
>> @@ -1164,7 +1130,7 @@ static const struct v4l2_subdev_core_ops ov9282_core_ops = {
>>   };
>>
>>   static const struct v4l2_subdev_video_ops ov9282_video_ops = {
>> -       .s_stream = ov9282_set_stream,
>> +       .s_stream = v4l2_subdev_s_stream_helper,
>>   };
>>
>>   static const struct v4l2_subdev_pad_ops ov9282_pad_ops = {
>> @@ -1173,6 +1139,8 @@ static const struct v4l2_subdev_pad_ops ov9282_pad_ops = {
>>          .get_fmt = ov9282_get_pad_format,
>>          .set_fmt = ov9282_set_pad_format,
>>          .get_selection = ov9282_get_selection,
>> +       .enable_streams = ov9282_enable_streams,
>> +       .disable_streams = ov9282_disable_streams,
>>   };
>>
>>   static const struct v4l2_subdev_ops ov9282_subdev_ops = {
>> --
>> 2.43.0
> Reviewed-by: Tarang Raval <tarang.raval@siliconsignals.io>
>
> Best Regards,
> Tarang