Re: [PATCH v1 11/15] media: i2c: imx290: Use V4L2 subdev active state

Alexander Stein
2022-11-23T08:42:14Z

Hello Laurent,

thanks for working on this.

Am Dienstag, 22. November 2022, 23:32:46 CET schrieb Laurent Pinchart:
> Use the V4L2 subdev active state API to store the active format. This
> simplifies the driver not only by dropping the imx290 current_format
> field, but it also allows dropping the imx290 lock, replaced with the
> state lock.
>
> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> ---
> drivers/media/i2c/imx290.c | 139 +++++++++++++++----------------------
> 1 file changed, 56 insertions(+), 83 deletions(-)
>
> diff --git a/drivers/media/i2c/imx290.c b/drivers/media/i2c/imx290.c
> index 848de4c90d3b..cd2154983341 100644
> --- a/drivers/media/i2c/imx290.c
> +++ b/drivers/media/i2c/imx290.c
> @@ -177,12 +177,12 @@ struct imx290 {
> struct clk *xclk;
> struct regmap *regmap;
> u8 nlanes;
> - u8 bpp;
>
> struct v4l2_subdev sd;
> struct media_pad pad;
> - struct v4l2_mbus_framefmt current_format;
> +
> const struct imx290_mode *current_mode;
> + u8 bpp;
>
> struct regulator_bulk_data supplies[IMX290_NUM_SUPPLIES];
> struct gpio_desc *rst_gpio;
> @@ -192,8 +192,6 @@ struct imx290 {
> struct v4l2_ctrl *pixel_rate;
> struct v4l2_ctrl *hblank;
> struct v4l2_ctrl *vblank;
> -
> - struct mutex lock;
> };
>
> static inline struct imx290 *to_imx290(struct v4l2_subdev *_sd)
> @@ -524,14 +522,15 @@ static int imx290_set_black_level(struct imx290
> *imx290, black_level >> (16 - imx290->bpp), err);
> }
>
> -static int imx290_write_current_format(struct imx290 *imx290)
> +static int imx290_setup_format(struct imx290 *imx290,
> + const struct v4l2_mbus_framefmt *format)
> {
> const struct imx290_regval *regs;
> unsigned int num_regs;
> unsigned int bpp;
> int ret;
>
> - switch (imx290->current_format.code) {
> + switch (format->code) {
> case MEDIA_BUS_FMT_SRGGB10_1X10:
> regs = imx290_10bit_settings;
> num_regs = ARRAY_SIZE(imx290_10bit_settings);
> @@ -564,12 +563,17 @@ static int imx290_set_ctrl(struct v4l2_ctrl *ctrl)
> {
> struct imx290 *imx290 = container_of(ctrl->handler,
> struct imx290, ctrls);
> + const struct v4l2_mbus_framefmt *format;
> + struct v4l2_subdev_state *state;
> int ret = 0;
>
> /* V4L2 controls values will be applied only when power is already
up */
> if (!pm_runtime_get_if_in_use(imx290->dev))
> return 0;
>
> + state = v4l2_subdev_get_locked_active_state(&imx290->sd);
> + format = v4l2_subdev_get_pad_format(&imx290->sd, state, 0);
> +
> switch (ctrl->id) {
> case V4L2_CID_ANALOGUE_GAIN:
> ret = imx290_write(imx290, IMX290_GAIN, ctrl->val, NULL);
> @@ -646,11 +650,10 @@ static int imx290_ctrl_init(struct imx290 *imx290)
> int ret;
>
> ret = v4l2_fwnode_device_parse(imx290->dev, &props);
> - if (ret < 0)
> + if (ret)

This is an unrelated change.

> return ret;
>
> v4l2_ctrl_handler_init(&imx290->ctrls, 9);
> - imx290->ctrls.lock = &imx290->lock;
>
> /*
> * The sensor has an analog gain and a digital gain, both controlled
> @@ -715,11 +718,6 @@ static int imx290_ctrl_init(struct imx290 *imx290)
> return ret;
> }
>
> - mutex_lock(imx290->ctrls.lock);
> - imx290_ctrl_update(imx290, &imx290->current_format,
> - imx290->current_mode);
> - mutex_unlock(imx290->ctrls.lock);
> -
> return 0;
> }
>
> @@ -728,8 +726,10 @@ static int imx290_ctrl_init(struct imx290 *imx290)
> */
>
> /* Start streaming */
> -static int imx290_start_streaming(struct imx290 *imx290)
> +static int imx290_start_streaming(struct imx290 *imx290,
> + struct v4l2_subdev_state *state)
> {
> + const struct v4l2_mbus_framefmt *format;
> int ret;
>
> /* Set init register settings */
> @@ -742,7 +742,8 @@ static int imx290_start_streaming(struct imx290 *imx290)
> }
>
> /* Apply the register values related to current frame format */
> - ret = imx290_write_current_format(imx290);
> + format = v4l2_subdev_get_pad_format(&imx290->sd, state, 0);
> + ret = imx290_setup_format(imx290, format);
> if (ret < 0) {
> dev_err(imx290->dev, "Could not set frame format\n");
> return ret;
> @@ -762,7 +763,7 @@ static int imx290_start_streaming(struct imx290 *imx290)
> return ret;
>
> /* Apply customized values from user */
> - ret = v4l2_ctrl_handler_setup(imx290->sd.ctrl_handler);
> + ret = __v4l2_ctrl_handler_setup(imx290->sd.ctrl_handler);

Why is it safe to ignore the lock now? There is no user-specified lock for
imx290->ctrls.lock, but instead imx290->ctrls._lock is set, no?

> if (ret) {
> dev_err(imx290->dev, "Could not sync v4l2 controls\n");
> return ret;
> @@ -791,39 +792,32 @@ static int imx290_stop_streaming(struct imx290
> *imx290) static int imx290_set_stream(struct v4l2_subdev *sd, int enable)
> {
> struct imx290 *imx290 = to_imx290(sd);
> + struct v4l2_subdev_state *state;
> int ret = 0;
>
> + state = v4l2_subdev_lock_and_get_active_state(sd);
> +
> if (enable) {
> ret = pm_runtime_resume_and_get(imx290->dev);
> if (ret < 0)
> - goto unlock_and_return;
> + goto unlock;
>
> - ret = imx290_start_streaming(imx290);
> + ret = imx290_start_streaming(imx290, state);
> if (ret) {
> dev_err(imx290->dev, "Start stream failed\n");
> pm_runtime_put(imx290->dev);
> - goto unlock_and_return;
> + goto unlock;
> }
> } else {
> imx290_stop_streaming(imx290);
> pm_runtime_put(imx290->dev);
> }
>
> -unlock_and_return:
> -
> +unlock:
> + v4l2_subdev_unlock_state(state);
> return ret;
> }
>
> -static struct v4l2_mbus_framefmt *
> -imx290_get_pad_format(struct imx290 *imx290, struct v4l2_subdev_state
> *state, - u32 which)
> -{
> - if (which == V4L2_SUBDEV_FORMAT_ACTIVE)
> - return &imx290->current_format;
> - else
> - return v4l2_subdev_get_try_format(&imx290->sd, state, 0);
> -}
> -
> static int imx290_enum_mbus_code(struct v4l2_subdev *sd,
> struct v4l2_subdev_state *sd_state,
> struct v4l2_subdev_mbus_code_enum
*code)
> @@ -858,23 +852,6 @@ static int imx290_enum_frame_size(struct v4l2_subdev
> *sd, return 0;
> }
>
> -static int imx290_get_fmt(struct v4l2_subdev *sd,
> - struct v4l2_subdev_state *sd_state,
> - struct v4l2_subdev_format *fmt)
> -{
> - struct imx290 *imx290 = to_imx290(sd);
> - struct v4l2_mbus_framefmt *framefmt;
> -
> - mutex_lock(&imx290->lock);
> -
> - framefmt = imx290_get_pad_format(imx290, sd_state, fmt->which);
> - fmt->format = *framefmt;
> -
> - mutex_unlock(&imx290->lock);
> -
> - return 0;
> -}
> -
> static int imx290_set_fmt(struct v4l2_subdev *sd,
> struct v4l2_subdev_state *sd_state,
> struct v4l2_subdev_format *fmt)
> @@ -884,8 +861,6 @@ static int imx290_set_fmt(struct v4l2_subdev *sd,
> struct v4l2_mbus_framefmt *format;
> unsigned int i;
>
> - mutex_lock(&imx290->lock);
> -
> mode = v4l2_find_nearest_size(imx290_modes_ptr(imx290),
> imx290_modes_num(imx290), width,
height,
> fmt->format.width, fmt-
>format.height);
> @@ -903,7 +878,7 @@ static int imx290_set_fmt(struct v4l2_subdev *sd,
> fmt->format.code = imx290_formats[i].code;
> fmt->format.field = V4L2_FIELD_NONE;
>
> - format = imx290_get_pad_format(imx290, sd_state, fmt->which);
> + format = v4l2_subdev_get_pad_format(sd, sd_state, 0);
>
> if (fmt->which == V4L2_SUBDEV_FORMAT_ACTIVE) {
> imx290->current_mode = mode;
> @@ -914,8 +889,6 @@ static int imx290_set_fmt(struct v4l2_subdev *sd,
>
> *format = fmt->format;
>
> - mutex_unlock(&imx290->lock);
> -
> return 0;
> }
>
> @@ -923,14 +896,11 @@ static int imx290_get_selection(struct v4l2_subdev
> *sd, struct v4l2_subdev_state *sd_state,
> struct v4l2_subdev_selection *sel)
> {
> - struct imx290 *imx290 = to_imx290(sd);
> struct v4l2_mbus_framefmt *format;
>
> switch (sel->target) {
> case V4L2_SEL_TGT_CROP: {
> - format = imx290_get_pad_format(imx290, sd_state, sel-
>which);
> -
> - mutex_lock(&imx290->lock);
> + format = v4l2_subdev_get_pad_format(sd, sd_state, 0);
>
> sel->r.top = IMX920_PIXEL_ARRAY_MARGIN_TOP
> + (IMX290_PIXEL_ARRAY_RECORDING_HEIGHT -
format->height) / 2;
> @@ -939,7 +909,6 @@ static int imx290_get_selection(struct v4l2_subdev *sd,
> sel->r.width = format->width;
> sel->r.height = format->height;
>
> - mutex_unlock(&imx290->lock);
> return 0;
> }
>
> @@ -968,11 +937,13 @@ static int imx290_get_selection(struct v4l2_subdev
> *sd, static int imx290_entity_init_cfg(struct v4l2_subdev *subdev,
> struct v4l2_subdev_state *sd_state)
> {
> - struct v4l2_subdev_format fmt = { 0 };
> -
> - fmt.which = sd_state ? V4L2_SUBDEV_FORMAT_TRY :
V4L2_SUBDEV_FORMAT_ACTIVE;
> - fmt.format.width = 1920;
> - fmt.format.height = 1080;
> + struct v4l2_subdev_format fmt = {
> + .which = V4L2_SUBDEV_FORMAT_TRY,
> + .format = {
> + .width = 1920,
> + .height = 1080,
> + },
> + };
>
> imx290_set_fmt(subdev, sd_state, &fmt);
>
> @@ -987,7 +958,7 @@ static const struct v4l2_subdev_pad_ops imx290_pad_ops =
> { .init_cfg = imx290_entity_init_cfg,
> .enum_mbus_code = imx290_enum_mbus_code,
> .enum_frame_size = imx290_enum_frame_size,
> - .get_fmt = imx290_get_fmt,
> + .get_fmt = v4l2_subdev_get_fmt,
> .set_fmt = imx290_set_fmt,
> .get_selection = imx290_get_selection,
> };
> @@ -1004,20 +975,12 @@ static const struct media_entity_operations
> imx290_subdev_entity_ops = { static int imx290_subdev_init(struct imx290
> *imx290)
> {
> struct i2c_client *client = to_i2c_client(imx290->dev);
> + const struct v4l2_mbus_framefmt *format;
> + struct v4l2_subdev_state *state;
> int ret;
>
> - /*
> - * Initialize the frame format. In particular, imx290->current_mode
> - * and imx290->bpp are set to defaults: imx290_calc_pixel_rate()
call
> - * below relies on these fields.
> - */
> - imx290_entity_init_cfg(&imx290->sd, NULL);
> -
> - ret = imx290_ctrl_init(imx290);
> - if (ret < 0) {
> - dev_err(imx290->dev, "Control initialization error %d\n",
ret);
> - return ret;
> - }
> + imx290->current_mode = &imx290_modes_ptr(imx290)[0];
> + imx290->bpp = imx290_formats[0].bpp;
>
> v4l2_i2c_subdev_init(&imx290->sd, client, &imx290_subdev_ops);
> imx290->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
> @@ -1032,6 +995,22 @@ static int imx290_subdev_init(struct imx290 *imx290)
> return ret;
> }
>
> + ret = imx290_ctrl_init(imx290);
> + if (ret < 0) {
> + dev_err(imx290->dev, "Control initialization error %d\n",
ret);
> + media_entity_cleanup(&imx290->sd.entity);
> + return ret;
> + }
> +
> + imx290->sd.state_lock = imx290->ctrls.lock;
> +
> + v4l2_subdev_init_finalize(&imx290->sd);
> +
> + state = v4l2_subdev_lock_and_get_active_state(&imx290->sd);
> + format = v4l2_subdev_get_pad_format(&imx290->sd, state, 0);
> + imx290_ctrl_update(imx290, format, imx290->current_mode);
> + v4l2_subdev_unlock_state(state);

Do you need to check for state == NULL here?

> +
> return 0;
> }
>
> @@ -1268,12 +1247,10 @@ static int imx290_probe(struct i2c_client *client)
> if (ret)
> return ret;
>
> - mutex_init(&imx290->lock);
> -
> /* Initialize and register subdev. */
> ret = imx290_subdev_init(imx290);
> if (ret)
> - goto err_mutex;
> + return ret;
>
> ret = v4l2_async_register_subdev(&imx290->sd);
> if (ret < 0) {
> @@ -1305,8 +1282,6 @@ static int imx290_probe(struct i2c_client *client)
>
> err_subdev:
> imx290_subdev_cleanup(imx290);
> -err_mutex:
> - mutex_destroy(&imx290->lock);
>
> return ret;
> }
> @@ -1319,8 +1294,6 @@ static void imx290_remove(struct i2c_client *client)
> v4l2_async_unregister_subdev(sd);
> imx290_subdev_cleanup(imx290);
>
> - mutex_destroy(&imx290->lock);
> -
> pm_runtime_disable(imx290->dev);
> if (!pm_runtime_status_suspended(imx290->dev))
> imx290_power_off(imx290->dev);