Re: [PATCH] [i2c] viperboard: Add error handling in vprbrd_i2c_probe

[Andi Shyti]

Hi Haoran,

the patch makes sense, but...

On Sun, Dec 03, 2023 at 01:12:08AM -0800, Haoran Liu wrote:
> This patch introduces improved error handling for the i2c_add_adapter.
> The necessity for this enhancement was identified through static analysis,
> revealing that the function previously did not properly manage potential
> failures of i2c_add_adapter. Prior to this patch, a failure in
> i2c_add_adapter could result in partial initialization of the I2C adapter,
> leading to unstable operation.

Please use the imperative form. Instead of starting with 'This
patch introduces...' you can write something like 'Check the
return value of i2c_add_adapter...'.

"Check" is in imperative form.

Using the imperative form is crucial for a clear understanding of
what the patch accomplishes.

> Although the error addressed by this patch may not occur in the current
> environment, I still suggest implementing these error handling routines
> if the function is not highly time-sensitive. As the environment evolves
> or the code gets reused in different contexts, there's a possibility that
> these errors might occur. In case you find this addition unnecessary, I
> completely understand and respect your perspective. My intention was to
> enhance the robustness of the code, but I acknowledge that practical
> considerations and current functionality might not warrant this change
> at this point.

The second paragraph does not describe anything functional
related to the patch; it's a message to the reviewers. Please add
it after the '---' section.

> Signed-off-by: Haoran Liu <liuhaoran14@xxxxxxx>
> ---
>  drivers/i2c/busses/i2c-viperboard.c | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/i2c/busses/i2c-viperboard.c b/drivers/i2c/busses/i2c-viperboard.c
> index 9e153b5b0e8e..13a07290ecf6 100644
> --- a/drivers/i2c/busses/i2c-viperboard.c
> +++ b/drivers/i2c/busses/i2c-viperboard.c
> @@ -400,7 +400,11 @@ static int vprbrd_i2c_probe(struct platform_device *pdev)
>  	vb_i2c->i2c.dev.parent = &pdev->dev;
>  
>  	/* attach to i2c layer */
> -	i2c_add_adapter(&vb_i2c->i2c);
> +	ret = i2c_add_adapter(&vb_i2c->i2c);
> +	if (ret) {
> +		dev_err(&pdev->dev, "i2c_add_adapter failed: %d\n", ret);

Please use:

	return dev_err_probe(&pdev->dev, ret, "...");

Additionally, I suggest rewording the error message to something
that might be more meaningful for non-kernel developers, such as:
"Failed to register the i2c adapter"

Thanks,
Andi

> +		return ret;
> +	}
>  
>  	platform_set_drvdata(pdev, vb_i2c);
>  
> -- 
> 2.17.1
>