Re: [PATCH v2] Input: zinitix - Don't fail if linux,keycodes prop is absent

[Yassine Oudjana]

From: Yassine Oudjana <y.oudjana@xxxxxxxxxxxxxx>

On 04/10/2024 7:17 pm, Nikita Travkin wrote:
> When initially adding the touchkey support, a mistake was made in the
> property parsing code. The possible negative errno from
> device_property_count_u32() was never checked, which was an oversight
> left from converting to it from the of_property as part of the review
> fixes.
>
> Re-add the correct handling of the absent property, in which case zero
> touchkeys should be assumed, which would disable the feature.
>
> Reported-by: Jakob Hauser <jahau@xxxxxxxxxxxxxx>
> Tested-by: Jakob Hauser <jahau@xxxxxxxxxxxxxx>
> Fixes: 075d9b22c8fe ("Input: zinitix - add touchkey support")
> Reviewed-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
> Signed-off-by: Nikita Travkin <nikita@xxxxxxx>

Tested-by: Yassine Oudjana <y.oudjana@xxxxxxxxxxxxxx>

> ---
> Changes in v2:
> - Refactored the change to simplify the code (Dmitry)
> - Link to v1: https://lore.kernel.org/r/20241002-zinitix-no-keycodes-v1-1-e84029601491@xxxxxxx
> ---
>   drivers/input/touchscreen/zinitix.c | 34 ++++++++++++++++++++++------------
>   1 file changed, 22 insertions(+), 12 deletions(-)
>
>
> ---
> base-commit: fe21733536749bb1b31c9c84e0b8d2ab8d82ce13
> change-id: 20241002-zinitix-no-keycodes-f0fe1bdaccb2
>
> Best regards,
>
> diff --git a/drivers/input/touchscreen/zinitix.c b/drivers/input/touchscreen/zinitix.c
> index 52b3950460e2..716d6fa60f86 100644
> --- a/drivers/input/touchscreen/zinitix.c
> +++ b/drivers/input/touchscreen/zinitix.c
> @@ -645,19 +645,29 @@ static int zinitix_ts_probe(struct i2c_client *client)
>   		return error;
>   	}
>   
> -	bt541->num_keycodes = device_property_count_u32(&client->dev, "linux,keycodes");
> -	if (bt541->num_keycodes > ARRAY_SIZE(bt541->keycodes)) {
> -		dev_err(&client->dev, "too many keys defined (%d)\n", bt541->num_keycodes);
> -		return -EINVAL;
> -	}
> +	if (device_property_present(&client->dev, "linux,keycodes")) {
> +		bt541->num_keycodes = device_property_count_u32(&client->dev,
> +								"linux,keycodes");
> +		if (bt541->num_keycodes < 0) {
> +			dev_err(&client->dev, "Failed to count keys (%d)\n",
> +				bt541->num_keycodes);
> +			return bt541->num_keycodes;
> +		} else if (bt541->num_keycodes > ARRAY_SIZE(bt541->keycodes)) {
> +			dev_err(&client->dev, "Too many keys defined (%d)\n",
> +				bt541->num_keycodes);
> +			return -EINVAL;
> +		}
>   
> -	error = device_property_read_u32_array(&client->dev, "linux,keycodes",
> -					       bt541->keycodes,
> -					       bt541->num_keycodes);
> -	if (error) {
> -		dev_err(&client->dev,
> -			"Unable to parse \"linux,keycodes\" property: %d\n", error);
> -		return error;
> +		error = device_property_read_u32_array(&client->dev,
> +						       "linux,keycodes",
> +						       bt541->keycodes,
> +						       bt541->num_keycodes);
> +		if (error) {
> +			dev_err(&client->dev,
> +				"Unable to parse \"linux,keycodes\" property: %d\n",
> +				error);
> +			return error;
> +		}
>   	}
>   
>   	error = zinitix_init_input_dev(bt541);