Dmitry Torokhov писал(а) 03.10.2024 16:43:
> Hi Nikita,
>
> On Wed, Oct 02, 2024 at 06:01:48PM +0500, 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")
>> Signed-off-by: Nikita Travkin <nikita@xxxxxxx>
>> ---
>> drivers/input/touchscreen/zinitix.c | 33 ++++++++++++++++++++++-----------
>> 1 file changed, 22 insertions(+), 11 deletions(-)
>>
>> diff --git a/drivers/input/touchscreen/zinitix.c b/drivers/input/touchscreen/zinitix.c
>> index 52b3950460e2..1f726653940c 100644
>> --- a/drivers/input/touchscreen/zinitix.c
>> +++ b/drivers/input/touchscreen/zinitix.c
>> @@ -645,19 +645,30 @@ 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;
>> + error = device_property_count_u32(&client->dev, "linux,keycodes");
>> + if (error == -EINVAL || error == -ENODATA) {
>> + bt541->num_keycodes = 0;
>> + } else if (error < 0) {
>> + dev_err(&client->dev, "Failed to count \"linux,keycodes\" property: %d\n", error);
>> + return error;
>> + } else {
>> + bt541->num_keycodes = 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;
>> + if (bt541->num_keycodes > 0) {
>
> I think this check is not needed and "if" can be folded into "else"
> above. But anyways, do you mind if I rewrite it as follows:
>
> ...
>
> n_keycodes = device_property_count_u32(&client->dev, "linux,keycodes");
> if (n_keycodes < 0) {
> error = n_keycodes;
> if (error != -EINVAL && error != -ENODATA) {
> dev_err(&client->dev,
> "Failed to count \"linux,keycodes\" property: %d\n",
> error);
> return error;
> }
> } else if (n_keycodes > 0) {
> if (n_keycodes > ARRAY_SIZE(bt541->keycodes)) {
> dev_err(&client->dev,
> "too many keys defined (%d)\n", n_keycodes);
> return -EINVAL;
> }
>
> error = device_property_read_u32_array(&client->dev,
> "linux,keycodes",
> bt541->keycodes,
> n_keycodes);
> if (error) {
> dev_err(&client->dev,
> "Unable to parse \"linux,keycodes\" property: %d\n",
> error);
> return error;
> }
>
> bt541->num_keycodes = n_keycodes;
> }
>
>
> Or maybe to avoid checking for specific error codes we should do:
>
> if (device_property_present(&client->dev, "linux,keycodes")) {
> bt541->num_keycodes = device_property_count_u32(&client->dev,
> "linux,keycodes");
> if (bt541->num_keycodes < 0) {
> error = bt541->num_keycodes;
> dev_err(&client->dev, ...);
> return error;
> }
>
> ...
> }
>
Oh, yeah, I didn't think of that but explicitly checking the presence
makes the code easier to read. I think both options are fine but I'd
prefer the (imo) easier to read second one. Should I submit a v2 or
you're planning to fast-track it?
Thank you for looking at this!
Nikita
>
> Thanks.
