Hi Pavel,
On 26 October 2018 at 05:24, Pavel Machek <pavel@xxxxxx> wrote:
>
> We don't want brightness < 0, but this may not be best way to do
> this. We also don't want brightness > max_brightness, but I'm not sure
> this check is effective.
I think this is reasonable, but we can simplify the patch as:
diff --git a/drivers/leds/trigger/ledtrig-pattern.c
b/drivers/leds/trigger/ledtrig-pattern.c
index ce7acd1..3a4ecb9 100644
--- a/drivers/leds/trigger/ledtrig-pattern.c
+++ b/drivers/leds/trigger/ledtrig-pattern.c
@@ -250,10 +250,11 @@ static ssize_t
pattern_trig_store_patterns(struct led_classdev *led_cdev,
while (offset < count - 1 && data->npatterns < MAX_PATTERNS) {
cr = 0;
- ccount = sscanf(buf + offset, "%d %u %n",
+ ccount = sscanf(buf + offset, "%u %u %n",
&data->patterns[data->npatterns].brightness,
&data->patterns[data->npatterns].delta_t, &cr);
- if (ccount != 2) {
+ if (ccount != 2 ||
+ data->patterns[data->npatterns].brightness >
data->led_cdev->max_brightness) {
data->npatterns = 0;
err = -EINVAL;
goto out;
>
> We probably also don't want pattern where all the delta_t s are zero.
Yes. Maybe add one function to valid the patterns.
>
> I came up with this so far....
> Pavel
>
>
>
> diff --git a/drivers/leds/trigger/ledtrig-pattern.c b/drivers/leds/trigger/ledtrig-pattern.c
> index ce7acd1..bc5f495 100644
> --- a/drivers/leds/trigger/ledtrig-pattern.c
> +++ b/drivers/leds/trigger/ledtrig-pattern.c
> @@ -250,9 +251,16 @@ static ssize_t pattern_trig_store_patterns(struct led_classdev *led_cdev,
>
> while (offset < count - 1 && data->npatterns < MAX_PATTERNS) {
> cr = 0;
> - ccount = sscanf(buf + offset, "%d %u %n",
> + ccount = sscanf(buf + offset, "%u %u %n",
> &data->patterns[data->npatterns].brightness,
> &data->patterns[data->npatterns].delta_t, &cr);
> +
> + if (data->patterns[data->npatterns].brightness > data->led_cdev->max_brightness) {
> + data->npatterns = 0;
> + err = -EINVAL;
> + goto out;
> + }
> +
> if (ccount != 2) {
> data->npatterns = 0;
> err = -EINVAL;
>
>
>
>
> --
> (english) http://www.livejournal.com/~pavelmachek
> (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
--
Baolin Wang
Best Regards
