Re: [PATCH v2 4/5] Input: hynitron-cst816x: time out gesture key release

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Low] timers: use timer_shutdown_sync() for devres teardown path
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commit f56704648dd845b470f4641ef231af0c72507d76
Author: Daniel Golle <daniel@makrotopia.org>

Input: hynitron-cst816x: time out gesture key release

This commit introduces a timer to release the gesture keys 40 ms after the
last report containing a gesture code. This prevents the gesture key from
remaining pressed indefinitely if the panel stops reporting after the
initial gesture event.

> diff --git a/drivers/input/touchscreen/hynitron-cst816x.c b/drivers/input/touchscreen/hynitron-cst816x.c
> --- a/drivers/input/touchscreen/hynitron-cst816x.c
> +++ b/drivers/input/touchscreen/hynitron-cst816x.c
[ ... ]
> +static void cst816x_timer_stop(void *data)
> +{
> +	struct cst816x_priv *priv = data;
> +
> +	timer_delete_sync(&priv->release_timer);

[Severity: Low]
Does this devres teardown path need to use timer_shutdown_sync() instead of
timer_delete_sync()?

Using timer_delete_sync() in a final teardown path is deprecated. The timer
subsystem introduced timer_shutdown_sync() to permanently disable timers
during teardown.

Because devres executes actions in last-in, first-out order, the interrupt
is already freed and synchronized before the timer is stopped. A re-arm race
is structurally impossible here, making this an API compliance regression
rather than a use-after-free bug.

> +}
> +
>  static int cst816x_probe(struct i2c_client *client)

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Sashiko AI review · https://sashiko.dev/#/patchset/cover.1790944534.git.daniel@makrotopia.org?part=4