diff options
| author |   Paul Cercueil <paul@crapouillou.net> | 2021-03-21 16:06:34 -0700 |
|---|---|---|
| committer |   Dmitry Torokhov <dmitry.torokhov@gmail.com> | 2021-03-25 11:14:08 -0700 |
| commit | 019002f20cb5b9f78d39360aff244265d035e08a (patch) | |
| tree | 987ad16318d996060444852aa02b88e8a2a32673 /drivers/input/keyboard/gpio_keys.c | |
| parent | Input: gpio-keys - remove extra call to input_sync (diff) | |
| download | linux-dev-019002f20cb5b9f78d39360aff244265d035e08a.tar.xz linux-dev-019002f20cb5b9f78d39360aff244265d035e08a.zip | |
Input: gpio-keys - use hrtimer for release timer
Dealing with input, timing is important; if the button should be
released in one millisecond, then it should be done in one millisecond
and not a hundred milliseconds.
Therefore, the standard timer API is not really suitable for this task.
Convert the gpio-keys driver to use a hrtimer instead of the standard
timer to address this issue.
Note that by using a hard IRQ for the hrtimer callback, we can get rid
of the spin_lock_irqsave() and spin_unlock_irqrestore().
Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Link: https://lore.kernel.org/r/20210307222240.380583-2-paul@crapouillou.net
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Diffstat (limited to 'drivers/input/keyboard/gpio_keys.c')
| -rw-r--r-- | drivers/input/keyboard/gpio_keys.c | 27 |
1 files changed, 16 insertions, 11 deletions
diff --git a/drivers/input/keyboard/gpio_keys.c b/drivers/input/keyboard/gpio_keys.c index 7fcb2c35c5cc..4b92f49decef 100644 --- a/drivers/input/keyboard/gpio_keys.c +++ b/drivers/input/keyboard/gpio_keys.c @@ -8,6 +8,7 @@ #include <linux/module.h> +#include <linux/hrtimer.h> #include <linux/init.h> #include <linux/fs.h> #include <linux/interrupt.h> @@ -36,7 +37,7 @@ struct gpio_button_data { unsigned short *code; - struct timer_list release_timer; + struct hrtimer release_timer; unsigned int release_delay; /* in msecs, for IRQ-only buttons */ struct delayed_work work; @@ -146,7 +147,7 @@ static void gpio_keys_disable_button(struct gpio_button_data *bdata) if (bdata->gpiod) cancel_delayed_work_sync(&bdata->work); else - del_timer_sync(&bdata->release_timer); + hrtimer_cancel(&bdata->release_timer); bdata->disabled = true; } @@ -415,19 +416,20 @@ static irqreturn_t gpio_keys_gpio_isr(int irq, void *dev_id) return IRQ_HANDLED; } -static void gpio_keys_irq_timer(struct timer_list *t) +static enum hrtimer_restart gpio_keys_irq_timer(struct hrtimer *t) { - struct gpio_button_data *bdata = from_timer(bdata, t, release_timer); + struct gpio_button_data *bdata = container_of(t, + struct gpio_button_data, + release_timer); struct input_dev *input = bdata->input; - unsigned long flags; - spin_lock_irqsave(&bdata->lock, flags); if (bdata->key_pressed) { input_event(input, EV_KEY, *bdata->code, 0); input_sync(input); bdata->key_pressed = false; } - spin_unlock_irqrestore(&bdata->lock, flags); + + return HRTIMER_NORESTART; } static irqreturn_t gpio_keys_irq_isr(int irq, void *dev_id) @@ -457,8 +459,9 @@ static irqreturn_t gpio_keys_irq_isr(int irq, void *dev_id) } if (bdata->release_delay) - mod_timer(&bdata->release_timer, - jiffies + msecs_to_jiffies(bdata->release_delay)); + hrtimer_start(&bdata->release_timer, + ms_to_ktime(bdata->release_delay), + HRTIMER_MODE_REL_HARD); out: spin_unlock_irqrestore(&bdata->lock, flags); return IRQ_HANDLED; @@ -471,7 +474,7 @@ static void gpio_keys_quiesce_key(void *data) if (bdata->gpiod) cancel_delayed_work_sync(&bdata->work); else - del_timer_sync(&bdata->release_timer); + hrtimer_cancel(&bdata->release_timer); } static int gpio_keys_setup_key(struct platform_device *pdev, @@ -595,7 +598,9 @@ static int gpio_keys_setup_key(struct platform_device *pdev, } bdata->release_delay = button->debounce_interval; - timer_setup(&bdata->release_timer, gpio_keys_irq_timer, 0); + hrtimer_init(&bdata->release_timer, + CLOCK_REALTIME, HRTIMER_MODE_REL_HARD); + bdata->release_timer.function = gpio_keys_irq_timer; isr = gpio_keys_irq_isr; irqflags = 0; |