From 02b823a4d28ffb5fde5192799abd934d9de95630 Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Fri, 6 Jan 2017 20:08:11 +0100 Subject: [PATCH 12/16] Input: gpio_keys - Do not report wake button presses as evdev events If a button is a wake button, it may still be bouncing from the press to wakeup the device by the time the gpio interrupts get enabled again and / or the gpio_keys_report_state call from gpio_keys_resume may find the button still pressed and report this as a new press. This is undesirable, esp. since the powerbutton on tablets is typically a wakeup source and uses the gpio_keys driver on some tablets, leading to userspace immediately re-suspending the tablet after the powerbutton is pressed, due to it seeing a powerbutton press. This commit ignores wakeup button presses for the first 1 second after resume (and while resumed, as the workqueue may run before the resume function runs), avoiding this problem. Signed-off-by: Hans de Goede --- Note: maybe we should make WAKE_DEBOUNCE part of gpio_keys_button and only do this when drivers / platform-data set this to a non-zero value ? --- drivers/input/keyboard/gpio_keys.c | 49 ++++++++++++++++++++++++++++++++++++-- 1 file changed, 47 insertions(+), 2 deletions(-) diff --git a/drivers/input/keyboard/gpio_keys.c b/drivers/input/keyboard/gpio_keys.c index da3d362f21b1..e1488b534e7d 100644 --- a/drivers/input/keyboard/gpio_keys.c +++ b/drivers/input/keyboard/gpio_keys.c @@ -31,6 +31,8 @@ #include #include +#define WAKE_DEBOUNCE msecs_to_jiffies(1000) + struct gpio_button_data { const struct gpio_keys_button *button; struct input_dev *input; @@ -44,10 +46,14 @@ struct gpio_button_data { struct delayed_work work; unsigned int software_debounce; /* in msecs, for GPIO-driven buttons */ + unsigned long resume_time; /* in jiffies, for wakeup buttons */ + unsigned int irq; spinlock_t lock; bool disabled; bool key_pressed; + bool suspended; + bool resume_time_valid; }; struct gpio_keys_drvdata { @@ -356,6 +362,27 @@ static struct attribute_group gpio_keys_attr_group = { .attrs = gpio_keys_attrs, }; +static bool gpio_keys_ignore_wakeup_button_press(struct gpio_button_data *bdata) +{ + unsigned long flags; + bool ret = false; + + if (!bdata->button->wakeup) + return ret; + + spin_lock_irqsave(&bdata->lock, flags); + + if (bdata->suspended) + ret = true; /* Our resume method did not run yet */ + else if (bdata->resume_time_valid && + time_before(jiffies, bdata->resume_time + WAKE_DEBOUNCE)) + ret = true; /* Assume this is a wakeup press and ignore */ + + spin_unlock_irqrestore(&bdata->lock, flags); + + return ret; +} + static void gpio_keys_gpio_report_event(struct gpio_button_data *bdata) { const struct gpio_keys_button *button = bdata->button; @@ -370,6 +397,9 @@ static void gpio_keys_gpio_report_event(struct gpio_button_data *bdata) return; } + if (state && gpio_keys_ignore_wakeup_button_press(bdata)) + return; + if (type == EV_ABS) { if (state) input_event(input, type, button->code, button->value); @@ -429,6 +459,9 @@ static irqreturn_t gpio_keys_irq_isr(int irq, void *dev_id) BUG_ON(irq != bdata->irq); + if (gpio_keys_ignore_wakeup_button_press(bdata)) + return IRQ_HANDLED; + spin_lock_irqsave(&bdata->lock, flags); if (!bdata->key_pressed) { @@ -848,13 +881,18 @@ static int __maybe_unused gpio_keys_suspend(struct device *dev) { struct gpio_keys_drvdata *ddata = dev_get_drvdata(dev); struct input_dev *input = ddata->input; + unsigned long flags; int i; if (device_may_wakeup(dev)) { for (i = 0; i < ddata->pdata->nbuttons; i++) { struct gpio_button_data *bdata = &ddata->data[i]; - if (bdata->button->wakeup) + if (bdata->button->wakeup) { + spin_lock_irqsave(&bdata->lock, flags); + bdata->suspended = true; + spin_unlock_irqrestore(&bdata->lock, flags); enable_irq_wake(bdata->irq); + } } } else { mutex_lock(&input->mutex); @@ -870,14 +908,21 @@ static int __maybe_unused gpio_keys_resume(struct device *dev) { struct gpio_keys_drvdata *ddata = dev_get_drvdata(dev); struct input_dev *input = ddata->input; + unsigned long flags; int error = 0; int i; if (device_may_wakeup(dev)) { for (i = 0; i < ddata->pdata->nbuttons; i++) { struct gpio_button_data *bdata = &ddata->data[i]; - if (bdata->button->wakeup) + if (bdata->button->wakeup) { disable_irq_wake(bdata->irq); + spin_lock_irqsave(&bdata->lock, flags); + bdata->resume_time = jiffies; + bdata->resume_time_valid = true; + bdata->suspended = false; + spin_unlock_irqrestore(&bdata->lock, flags); + } } } else { mutex_lock(&input->mutex); -- 2.13.0