[PATCH v5 2/4] media: ov2640: add async probe function

[Guennadi Liakhovetski]

Hi Josh,

Thanks for a patch update. I think it looks good as a first step in your 
patch series, just a minor comment below:

On Tue, 10 Feb 2015, Josh Wu wrote:

> In async probe, there is a case that ov2640 is probed before the
> host device which provided 'mclk'.
> To support this async probe, we will get 'mclk' at first in the probe(),
> if failed it will return -EPROBE_DEFER. That will let ov2640 wait for
> the host device probed.
> 
> Signed-off-by: Josh Wu <josh.wu at atmel.com>
> ---
> 
> Changes in v5:
> - don't change the ov2640_s_power() code.
> - will get 'mclk' at the beginning of ov2640_probe().
> 
> Changes in v4: None
> Changes in v3: None
> Changes in v2: None
> 
>  drivers/media/i2c/soc_camera/ov2640.c | 29 +++++++++++++++++++----------
>  1 file changed, 19 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/media/i2c/soc_camera/ov2640.c b/drivers/media/i2c/soc_camera/ov2640.c
> index 1fdce2f..057dd49 100644
> --- a/drivers/media/i2c/soc_camera/ov2640.c
> +++ b/drivers/media/i2c/soc_camera/ov2640.c
> @@ -1068,6 +1068,10 @@ static int ov2640_probe(struct i2c_client *client,
>  		return -ENOMEM;
>  	}
>  
> +	priv->clk = v4l2_clk_get(&client->dev, "mclk");
> +	if (IS_ERR(priv->clk))
> +		return -EPROBE_DEFER;
> +
>  	v4l2_i2c_subdev_init(&priv->subdev, client, &ov2640_subdev_ops);
>  	v4l2_ctrl_handler_init(&priv->hdl, 2);
>  	v4l2_ctrl_new_std(&priv->hdl, &ov2640_ctrl_ops,
> @@ -1075,24 +1079,28 @@ static int ov2640_probe(struct i2c_client *client,
>  	v4l2_ctrl_new_std(&priv->hdl, &ov2640_ctrl_ops,
>  			V4L2_CID_HFLIP, 0, 1, 1, 0);
>  	priv->subdev.ctrl_handler = &priv->hdl;
> -	if (priv->hdl.error)
> -		return priv->hdl.error;
> -
> -	priv->clk = v4l2_clk_get(&client->dev, "mclk");
> -	if (IS_ERR(priv->clk)) {
> -		ret = PTR_ERR(priv->clk);
> -		goto eclkget;
> +	if (priv->hdl.error) {
> +		ret = priv->hdl.error;
> +		goto err_clk;
>  	}
>  
>  	ret = ov2640_video_probe(client);
>  	if (ret) {
> -		v4l2_clk_put(priv->clk);
> -eclkget:
> -		v4l2_ctrl_handler_free(&priv->hdl);
> +		goto err_videoprobe;

Since you add a "goto" here, you don't need an "else" after it, and the 
"probed" success message should go down, so, just make it

	ret = ov2640_video_probe(client);
	if (ret < 0)
		goto err_videoprobe;

	ret = v4l2_async_register_subdev(&priv->subdev);
	if (ret < 0)
		goto err_videoprobe;

	dev_info(&adapter->dev, "OV2640 Probed\n");

	return 0;

err_...

Thanks
Guennadi

>  	} else {
>  		dev_info(&adapter->dev, "OV2640 Probed\n");
>  	}
>  
> +	ret = v4l2_async_register_subdev(&priv->subdev);
> +	if (ret < 0)
> +		goto err_videoprobe;
> +
> +	return 0;
> +
> +err_videoprobe:
> +	v4l2_ctrl_handler_free(&priv->hdl);
> +err_clk:
> +	v4l2_clk_put(priv->clk);
>  	return ret;
>  }
>  
> @@ -1100,6 +1108,7 @@ static int ov2640_remove(struct i2c_client *client)
>  {
>  	struct ov2640_priv       *priv = to_ov2640(client);
>  
> +	v4l2_async_unregister_subdev(&priv->subdev);
>  	v4l2_clk_put(priv->clk);
>  	v4l2_device_unregister_subdev(&priv->subdev);
>  	v4l2_ctrl_handler_free(&priv->hdl);
> -- 
> 1.9.1
>