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

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Alexander,

On Wed, Nov 23, 2022 at 08:44:45AM +0100, Alexander Stein wrote:
> 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.

Good catch, and easy to fix. I'll handle it in v2.

> > +	}
> > +
> > +	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);

-- 
Regards,

Laurent Pinchart