Re: [PATCH v1 02/15] media: i2c: imx290: Factor out subdev init and cleanup to functions

Alexander Stein
2022-11-23T07:44:55Z

Hello Laurent,

thanks for working on this.

Am Dienstag, 22. November 2022, 23:32:37 CET schrieb Laurent Pinchart:
> The probe() function is large. Make it more readable by factoring the
> subdev initialization code out. While at it, rename the error labels as
> the "free_" prefix isn't accurate.
>
> No functional change intended.
>
> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> ---
> drivers/media/i2c/imx290.c | 109 +++++++++++++++++++++----------------
> 1 file changed, 62 insertions(+), 47 deletions(-)
>
> diff --git a/drivers/media/i2c/imx290.c b/drivers/media/i2c/imx290.c
> index aae4f51941a1..4dbf218e7a63 100644
> --- a/drivers/media/i2c/imx290.c
> +++ b/drivers/media/i2c/imx290.c
> @@ -1015,6 +1015,46 @@ static const struct media_entity_operations
> imx290_subdev_entity_ops = { .link_validate = v4l2_subdev_link_validate,
> };
>
> +static int imx290_subdev_init(struct imx290 *imx290)
> +{
> + struct i2c_client *client = to_i2c_client(imx290->dev);
> + 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;
> + }
> +
> + v4l2_i2c_subdev_init(&imx290->sd, client, &imx290_subdev_ops);
> + imx290->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
> + imx290->sd.dev = imx290->dev;
> + imx290->sd.entity.ops = &imx290_subdev_entity_ops;
> + imx290->sd.entity.function = MEDIA_ENT_F_CAM_SENSOR;
> +
> + imx290->pad.flags = MEDIA_PAD_FL_SOURCE;
> + ret = media_entity_pads_init(&imx290->sd.entity, 1, &imx290->pad);
> + if (ret < 0) {
> + dev_err(imx290->dev, "Could not register media entity\n");
> + return ret;

AFAICS in this error path v4l2_ctrl_handler_free is not called later on,
because imx290_subdev_cleanup is skipped due to goto err_mutex.

Regards,
Alexander

> + }
> +
> + return 0;
> +}
> +
> +static void imx290_subdev_cleanup(struct imx290 *imx290)
> +{
> + media_entity_cleanup(&imx290->sd.entity);
> + v4l2_ctrl_handler_free(&imx290->ctrls);
> +}
> +
> /*
> ---------------------------------------------------------------------------
> - * Power management
> */
> @@ -1148,10 +1188,10 @@ static int imx290_probe(struct i2c_client *client)
> fwnode_handle_put(endpoint);
> if (ret == -ENXIO) {
> dev_err(dev, "Unsupported bus type, should be CSI2\n");
> - goto free_err;
> + goto err_endpoint;
> } else if (ret) {
> dev_err(dev, "Parsing endpoint node failed\n");
> - goto free_err;
> + goto err_endpoint;
> }
>
> /* Get number of data lanes */
> @@ -1159,7 +1199,7 @@ static int imx290_probe(struct i2c_client *client)
> if (imx290->nlanes != 2 && imx290->nlanes != 4) {
> dev_err(dev, "Invalid data lanes: %d\n", imx290->nlanes);
> ret = -EINVAL;
> - goto free_err;
> + goto err_endpoint;
> }
>
> dev_dbg(dev, "Using %u data lanes\n", imx290->nlanes);
> @@ -1167,7 +1207,7 @@ static int imx290_probe(struct i2c_client *client)
> if (!ep.nr_of_link_frequencies) {
> dev_err(dev, "link-frequency property not found in DT\n");
> ret = -EINVAL;
> - goto free_err;
> + goto err_endpoint;
> }
>
> /* Check that link frequences for all the modes are in device tree
*/
> @@ -1175,7 +1215,7 @@ static int imx290_probe(struct i2c_client *client)
> if (fq) {
> dev_err(dev, "Link frequency of %lld is not supported\n",
fq);
> ret = -EINVAL;
> - goto free_err;
> + goto err_endpoint;
> }
>
> /* get system clock (xclk) */
> @@ -1183,14 +1223,14 @@ static int imx290_probe(struct i2c_client *client)
> if (IS_ERR(imx290->xclk)) {
> dev_err(dev, "Could not get xclk");
> ret = PTR_ERR(imx290->xclk);
> - goto free_err;
> + goto err_endpoint;
> }
>
> ret = fwnode_property_read_u32(dev_fwnode(dev), "clock-frequency",
> &xclk_freq);
> if (ret) {
> dev_err(dev, "Could not get xclk frequency\n");
> - goto free_err;
> + goto err_endpoint;
> }
>
> /* external clock must be 37.125 MHz */
> @@ -1198,19 +1238,19 @@ static int imx290_probe(struct i2c_client *client)
> dev_err(dev, "External clock frequency %u is not
supported\n",
> xclk_freq);
> ret = -EINVAL;
> - goto free_err;
> + goto err_endpoint;
> }
>
> ret = clk_set_rate(imx290->xclk, xclk_freq);
> if (ret) {
> dev_err(dev, "Could not set xclk frequency\n");
> - goto free_err;
> + goto err_endpoint;
> }
>
> ret = imx290_get_regulators(dev, imx290);
> if (ret < 0) {
> dev_err(dev, "Cannot get regulators\n");
> - goto free_err;
> + goto err_endpoint;
> }
>
> imx290->rst_gpio = devm_gpiod_get_optional(dev, "reset",
> @@ -1218,55 +1258,33 @@ static int imx290_probe(struct i2c_client *client)
> if (IS_ERR(imx290->rst_gpio)) {
> dev_err(dev, "Cannot get reset gpio\n");
> ret = PTR_ERR(imx290->rst_gpio);
> - goto free_err;
> + goto err_endpoint;
> }
>
> mutex_init(&imx290->lock);
>
> - /*
> - * 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(dev, "Control initialization error %d\n", ret);
> - goto free_mutex;
> - }
> -
> - v4l2_i2c_subdev_init(&imx290->sd, client, &imx290_subdev_ops);
> - imx290->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
> - imx290->sd.dev = &client->dev;
> - imx290->sd.entity.ops = &imx290_subdev_entity_ops;
> - imx290->sd.entity.function = MEDIA_ENT_F_CAM_SENSOR;
> -
> - imx290->pad.flags = MEDIA_PAD_FL_SOURCE;
> - ret = media_entity_pads_init(&imx290->sd.entity, 1, &imx290->pad);
> - if (ret < 0) {
> - dev_err(dev, "Could not register media entity\n");
> - goto free_ctrl;
> - }
> + ret = imx290_subdev_init(imx290);
> + if (ret)
> + goto err_mutex;
>
> ret = v4l2_async_register_subdev(&imx290->sd);
> if (ret < 0) {
> dev_err(dev, "Could not register v4l2 device\n");
> - goto free_entity;
> + goto err_subdev;
> }
>
> /* Power on the device to match runtime PM state below */
> ret = imx290_power_on(dev);
> if (ret < 0) {
> dev_err(dev, "Could not power on the device\n");
> - goto free_entity;
> + goto err_subdev;
> }
>
> ret = imx290_read(imx290, IMX290_CHIP_ID, &chip_id);
> if (ret) {
> dev_err(dev, "Could not read chip ID: %d\n", ret);
> imx290_power_off(dev);
> - goto free_entity;
> + goto err_subdev;
> }
>
> dev_info(dev, "chip ID 0x%04x\n", chip_id);
> @@ -1279,13 +1297,11 @@ static int imx290_probe(struct i2c_client *client)
>
> return 0;
>
> -free_entity:
> - media_entity_cleanup(&imx290->sd.entity);
> -free_ctrl:
> - v4l2_ctrl_handler_free(&imx290->ctrls);
> -free_mutex:
> +err_subdev:
> + imx290_subdev_cleanup(imx290);
> +err_mutex:
> mutex_destroy(&imx290->lock);
> -free_err:
> +err_endpoint:
> v4l2_fwnode_endpoint_free(&ep);
>
> return ret;
> @@ -1297,8 +1313,7 @@ static void imx290_remove(struct i2c_client *client)
> struct imx290 *imx290 = to_imx290(sd);
>
> v4l2_async_unregister_subdev(sd);
> - media_entity_cleanup(&sd->entity);
> - v4l2_ctrl_handler_free(sd->ctrl_handler);
> + imx290_subdev_cleanup(imx290);
>
> mutex_destroy(&imx290->lock);