From 25bb14c1e78e641049fd1ee0c404a9ccd2755e44 Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Sat, 22 Jul 2017 13:00:05 +0200 Subject: [PATCH 1/2] Input: gpio_keys - Allow suppression of input events for wakeup button presses In some cases it is undesirable for a wakeup button to send input events to userspace if pressed to wakeup the system (if pressed during suspend). A typical example of this is the power-button on laptops / tablets, sending a KEY_POWER event to userspace when woken up with the power-button will cause userspace to immediately suspend the system again which is undesirable. For power-buttons attached to a PMIC, or handled by e.g. ACPI, not sending an input event in this case is take care of by the PMIC / ACPI hardware / code. But in the case of a GPIO button we need to explicitly suppress the sending of the input event. This commit adds support for this by adding a no_wakeup_events bool to struct gpio_keys_button, which platform code can set to suppress the input events for presses of wakeup keys during suspend. Signed-off-by: Hans de Goede --- Changes in v2: -This is a rewrite if my "Input: gpio_keys - Do not report wake button presses as evdev events" patch. -Instead of unconditionally ignoring presses of all wake-up buttons during suspend, this rewrite makes this configurable per button -This version uses a timer to delay clearing the suspended flag for software debouncing, rather then jiffy compare magic --- drivers/input/keyboard/gpio_keys.c | 33 +++++++++++++++++++++++++++++++-- include/linux/gpio_keys.h | 3 +++ 2 files changed, 34 insertions(+), 2 deletions(-) diff --git a/drivers/input/keyboard/gpio_keys.c b/drivers/input/keyboard/gpio_keys.c index a047b9af8369..fa3a58620407 100644 --- a/drivers/input/keyboard/gpio_keys.c +++ b/drivers/input/keyboard/gpio_keys.c @@ -38,6 +38,7 @@ struct gpio_button_data { unsigned short *code; + struct timer_list unsuspend_timer; struct timer_list release_timer; unsigned int release_delay; /* in msecs, for IRQ-only buttons */ @@ -371,6 +372,9 @@ static void gpio_keys_gpio_report_event(struct gpio_button_data *bdata) return; } + if (state && bdata->button->no_wakeup_events && bdata->suspended) + return; + if (type == EV_ABS) { if (state) input_event(input, type, button->code, button->value); @@ -400,6 +404,9 @@ static irqreturn_t gpio_keys_gpio_isr(int irq, void *dev_id) if (bdata->button->wakeup) { const struct gpio_keys_button *button = bdata->button; + if (bdata->button->no_wakeup_events && bdata->suspended) + return IRQ_HANDLED; + pm_stay_awake(bdata->input->dev.parent); if (bdata->suspended && (button->type == 0 || button->type == EV_KEY)) { @@ -445,9 +452,13 @@ static irqreturn_t gpio_keys_irq_isr(int irq, void *dev_id) spin_lock_irqsave(&bdata->lock, flags); if (!bdata->key_pressed) { - if (bdata->button->wakeup) + if (bdata->button->wakeup) { pm_wakeup_event(bdata->input->dev.parent, 0); + if (bdata->button->no_wakeup_events && bdata->suspended) + goto out; + } + input_event(input, EV_KEY, *bdata->code, 1); input_sync(input); @@ -468,6 +479,13 @@ static irqreturn_t gpio_keys_irq_isr(int irq, void *dev_id) return IRQ_HANDLED; } +static void gpio_keys_unsuspend_timer(unsigned long _data) +{ + struct gpio_button_data *bdata = (struct gpio_button_data *)_data; + + bdata->suspended = false; +} + static void gpio_keys_quiesce_key(void *data) { struct gpio_button_data *bdata = data; @@ -476,6 +494,8 @@ static void gpio_keys_quiesce_key(void *data) cancel_delayed_work_sync(&bdata->work); else del_timer_sync(&bdata->release_timer); + + del_timer_sync(&bdata->unsuspend_timer); } static int gpio_keys_setup_key(struct platform_device *pdev, @@ -496,6 +516,8 @@ static int gpio_keys_setup_key(struct platform_device *pdev, bdata->input = input; bdata->button = button; spin_lock_init(&bdata->lock); + setup_timer(&bdata->unsuspend_timer, gpio_keys_unsuspend_timer, + (unsigned long)bdata); if (child) { bdata->gpiod = devm_fwnode_get_gpiod_from_child(dev, NULL, @@ -868,6 +890,7 @@ static int __maybe_unused gpio_keys_suspend(struct device *dev) struct gpio_button_data *bdata = &ddata->data[i]; if (bdata->button->wakeup) enable_irq_wake(bdata->irq); + del_timer_sync(&bdata->unsuspend_timer); bdata->suspended = true; } } else { @@ -892,7 +915,13 @@ static int __maybe_unused gpio_keys_resume(struct device *dev) struct gpio_button_data *bdata = &ddata->data[i]; if (bdata->button->wakeup) disable_irq_wake(bdata->irq); - bdata->suspended = false; + if (bdata->button->no_wakeup_events) { + mod_timer(&bdata->unsuspend_timer, jiffies + + msecs_to_jiffies( + bdata->software_debounce)); + } else { + bdata->suspended = false; + } } } else { mutex_lock(&input->mutex); diff --git a/include/linux/gpio_keys.h b/include/linux/gpio_keys.h index 0b71024c082c..d8a85e52b6bb 100644 --- a/include/linux/gpio_keys.h +++ b/include/linux/gpio_keys.h @@ -15,6 +15,8 @@ struct device; * @debounce_interval: debounce ticks interval in msecs * @can_disable: %true indicates that userspace is allowed to * disable button via sysfs + * @no_wakeup_events: For wake-up source buttons only, if %true then no input + * events will be generated if pressed while suspended * @value: axis value for %EV_ABS * @irq: Irq number in case of interrupt keys */ @@ -27,6 +29,7 @@ struct gpio_keys_button { int wakeup; int debounce_interval; bool can_disable; + bool no_wakeup_events; int value; unsigned int irq; }; -- 2.13.4