Re: [PATCH v2] media: davinci/vpfe_capture.c: Avoid BUG_ON for register failure

[Hans Verkuil]

On 12/17/19 11:12 PM, Aditya Pakki wrote:
> In vpfe_register_ccdc_device(), failure to allocate dev->hw_ops
> fields calls BUG_ON(). This patch returns the error to callers
> instead of crashing. The issue was identified by a static
> analysis tool.
> 
> Signed-off-by: Aditya Pakki <pakki001@xxxxxxx>
> ---
> v1: Fixed the type to a regular variable instead of a pointer,
> also added fixes suggested by Ezequiel Garcia.
> ---
>  drivers/media/platform/davinci/vpfe_capture.c | 31 ++++++++++---------
>  1 file changed, 16 insertions(+), 15 deletions(-)
> 
> diff --git a/drivers/media/platform/davinci/vpfe_capture.c b/drivers/media/platform/davinci/vpfe_capture.c
> index 916ed743d716..a3838a2e173f 100644
> --- a/drivers/media/platform/davinci/vpfe_capture.c
> +++ b/drivers/media/platform/davinci/vpfe_capture.c
> @@ -168,21 +168,22 @@ int vpfe_register_ccdc_device(const struct ccdc_hw_device *dev)
>  	int ret = 0;
>  	printk(KERN_NOTICE "vpfe_register_ccdc_device: %s\n", dev->name);
>  
> -	BUG_ON(!dev->hw_ops.open);
> -	BUG_ON(!dev->hw_ops.enable);
> -	BUG_ON(!dev->hw_ops.set_hw_if_params);
> -	BUG_ON(!dev->hw_ops.configure);
> -	BUG_ON(!dev->hw_ops.set_buftype);
> -	BUG_ON(!dev->hw_ops.get_buftype);
> -	BUG_ON(!dev->hw_ops.enum_pix);
> -	BUG_ON(!dev->hw_ops.set_frame_format);
> -	BUG_ON(!dev->hw_ops.get_frame_format);
> -	BUG_ON(!dev->hw_ops.get_pixel_format);
> -	BUG_ON(!dev->hw_ops.set_pixel_format);
> -	BUG_ON(!dev->hw_ops.set_image_window);
> -	BUG_ON(!dev->hw_ops.get_image_window);
> -	BUG_ON(!dev->hw_ops.get_line_length);
> -	BUG_ON(!dev->hw_ops.getfid);
> +	if (!dev->hw_ops.open ||
> +			!dev->hw_ops.enable ||
> +			!dev->hw_ops.set_hw_if_params ||
> +			!dev->hw_ops.configure ||
> +			!dev->hw_ops.set_buftype ||
> +			!dev->hw_ops.get_buftype ||
> +			!dev->hw_ops.enum_pix ||
> +			!dev->hw_ops.set_frame_format ||
> +			!dev->hw_ops.get_frame_format ||
> +			!dev->hw_ops.get_pixel_format ||
> +			!dev->hw_ops.set_pixel_format ||
> +			!dev->hw_ops.set_image_window ||
> +			!dev->hw_ops.get_image_window ||
> +			!dev->hw_ops.get_line_length ||
> +			!dev->hw_ops.getfid)

Please align this under !dev->hw_ops.open. E.g.:

	if (!dev->hw_ops.open ||
	    !dev->hw_ops.enable ||
	    !dev->hw_ops.set_hw_if_params ||
	    ...etc...

Regards,

	Hans


> +		return -EINVAL;
>  
>  	mutex_lock(&ccdc_lock);
>  	if (!ccdc_cfg) {
>