Input: gpio-keys - add support for wakeup event action

Add support for specifying event actions to trigger wakeup when using
the gpio-keys input device as a wakeup source.

This would allow the device to configure when to wakeup the system. For
example a gpio-keys input device for pen insert, may only want to wakeup
the system when ejecting the pen.

Suggested-by: Brian Norris <briannorris@chromium.org>
Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

diff --git a/Documentation/devicetree/bindings/input/gpio-keys.txt b/Documentation/devicetree/bindings/input/gpio-keys.txt
index a94940481e55ad6de187b3dc1a5c87a57c461fef..996ce84352cbf11627adc17c13d079cc17601de1 100644 (file)
--- a/Documentation/devicetree/bindings/input/gpio-keys.txt
+++ b/Documentation/devicetree/bindings/input/gpio-keys.txt
@@ -26,6 +26,14 @@ Optional subnode-properties:
          If not specified defaults to 5.
        - wakeup-source: Boolean, button can wake-up the system.
                         (Legacy property supported: "gpio-key,wakeup")
+       - wakeup-event-action: Specifies whether the key should wake the
+         system when asserted, when deasserted, or both. This property is
+         only valid for keys that wake up the system (e.g., when the
+         "wakeup-source" property is also provided).
+         Supported values are defined in linux-event-codes.h:
+               EV_ACT_ASSERTED         - asserted
+               EV_ACT_DEASSERTED       - deasserted
+               EV_ACT_ANY              - both asserted and deasserted
        - linux,can-disable: Boolean, indicates that button is connected
          to dedicated (not shared) interrupt which can be disabled to
          suppress events from the button.

diff --git a/drivers/input/keyboard/gpio_keys.c b/drivers/input/keyboard/gpio_keys.c
index 87e613dc33b804bf60047133f773343550e1a044..052e37675086bf53bc7d471d0434542167c6a88e 100644 (file)
--- a/drivers/input/keyboard/gpio_keys.c
+++ b/drivers/input/keyboard/gpio_keys.c
@@ -30,6 +30,7 @@
 #include <linux/of.h>
 #include <linux/of_irq.h>
 #include <linux/spinlock.h>
+#include <dt-bindings/input/gpio-keys.h>
 
 struct gpio_button_data {
        const struct gpio_keys_button *button;
@@ -45,6 +46,7 @@ struct gpio_button_data {
        unsigned int software_debounce; /* in msecs, for GPIO-driven buttons */
 
        unsigned int irq;
+       unsigned int wakeup_trigger_type;
        spinlock_t lock;
        bool disabled;
        bool key_pressed;
@@ -540,6 +542,8 @@ static int gpio_keys_setup_key(struct platform_device *pdev,
        }
 
        if (bdata->gpiod) {
+               bool active_low = gpiod_is_active_low(bdata->gpiod);
+
                if (button->debounce_interval) {
                        error = gpiod_set_debounce(bdata->gpiod,
                                        button->debounce_interval * 1000);
@@ -568,6 +572,24 @@ static int gpio_keys_setup_key(struct platform_device *pdev,
                isr = gpio_keys_gpio_isr;
                irqflags = IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING;
 
+               switch (button->wakeup_event_action) {
+               case EV_ACT_ASSERTED:
+                       bdata->wakeup_trigger_type = active_low ?
+                               IRQ_TYPE_EDGE_FALLING : IRQ_TYPE_EDGE_RISING;
+                       break;
+               case EV_ACT_DEASSERTED:
+                       bdata->wakeup_trigger_type = active_low ?
+                               IRQ_TYPE_EDGE_RISING : IRQ_TYPE_EDGE_FALLING;
+                       break;
+               case EV_ACT_ANY:
+                       /* fall through */
+               default:
+                       /*
+                        * For other cases, we are OK letting suspend/resume
+                        * not reconfigure the trigger type.
+                        */
+                       break;
+               }
        } else {
                if (!button->irq) {
                        dev_err(dev, "Found button without gpio or irq\n");
@@ -586,6 +608,11 @@ static int gpio_keys_setup_key(struct platform_device *pdev,
 
                isr = gpio_keys_irq_isr;
                irqflags = 0;
+
+               /*
+                * For IRQ buttons, there is no interrupt for release.
+                * So we don't need to reconfigure the trigger type for wakeup.
+                */
        }
 
        bdata->code = &ddata->keymap[idx];
@@ -718,6 +745,9 @@ gpio_keys_get_devtree_pdata(struct device *dev)
                        /* legacy name */
                        fwnode_property_read_bool(child, "gpio-key,wakeup");
 
+               fwnode_property_read_u32(child, "wakeup-event-action",
+                                        &button->wakeup_event_action);
+
                button->can_disable =
                        fwnode_property_read_bool(child, "linux,can-disable");
 
@@ -845,19 +875,112 @@ static int gpio_keys_probe(struct platform_device *pdev)
        return 0;
 }
 
+static int __maybe_unused
+gpio_keys_button_enable_wakeup(struct gpio_button_data *bdata)
+{
+       int error;
+
+       error = enable_irq_wake(bdata->irq);
+       if (error) {
+               dev_err(bdata->input->dev.parent,
+                       "failed to configure IRQ %d as wakeup source: %d\n",
+                       bdata->irq, error);
+               return error;
+       }
+
+       if (bdata->wakeup_trigger_type) {
+               error = irq_set_irq_type(bdata->irq,
+                                        bdata->wakeup_trigger_type);
+               if (error) {
+                       dev_err(bdata->input->dev.parent,
+                               "failed to set wakeup trigger %08x for IRQ %d: %d\n",
+                               bdata->wakeup_trigger_type, bdata->irq, error);
+                       disable_irq_wake(bdata->irq);
+                       return error;
+               }
+       }
+
+       return 0;
+}
+
+static void __maybe_unused
+gpio_keys_button_disable_wakeup(struct gpio_button_data *bdata)
+{
+       int error;
+
+       /*
+        * The trigger type is always both edges for gpio-based keys and we do
+        * not support changing wakeup trigger for interrupt-based keys.
+        */
+       if (bdata->wakeup_trigger_type) {
+               error = irq_set_irq_type(bdata->irq, IRQ_TYPE_EDGE_BOTH);
+               if (error)
+                       dev_warn(bdata->input->dev.parent,
+                                "failed to restore interrupt trigger for IRQ %d: %d\n",
+                                bdata->irq, error);
+       }
+
+       error = disable_irq_wake(bdata->irq);
+       if (error)
+               dev_warn(bdata->input->dev.parent,
+                        "failed to disable IRQ %d as wake source: %d\n",
+                        bdata->irq, error);
+}
+
+static int __maybe_unused
+gpio_keys_enable_wakeup(struct gpio_keys_drvdata *ddata)
+{
+       struct gpio_button_data *bdata;
+       int error;
+       int i;
+
+       for (i = 0; i < ddata->pdata->nbuttons; i++) {
+               bdata = &ddata->data[i];
+               if (bdata->button->wakeup) {
+                       error = gpio_keys_button_enable_wakeup(bdata);
+                       if (error)
+                               goto err_out;
+               }
+               bdata->suspended = true;
+       }
+
+       return 0;
+
+err_out:
+       while (i--) {
+               bdata = &ddata->data[i];
+               if (bdata->button->wakeup)
+                       gpio_keys_button_disable_wakeup(bdata);
+               bdata->suspended = false;
+       }
+
+       return error;
+}
+
+static void __maybe_unused
+gpio_keys_disable_wakeup(struct gpio_keys_drvdata *ddata)
+{
+       struct gpio_button_data *bdata;
+       int i;
+
+       for (i = 0; i < ddata->pdata->nbuttons; i++) {
+               bdata = &ddata->data[i];
+               bdata->suspended = false;
+               if (irqd_is_wakeup_set(irq_get_irq_data(bdata->irq)))
+                       gpio_keys_button_disable_wakeup(bdata);
+       }
+}
+
 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;
-       int i;
+       int error;
 
        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)
-                               enable_irq_wake(bdata->irq);
-                       bdata->suspended = true;
-               }
+               error = gpio_keys_enable_wakeup(ddata);
+               if (error)
+                       return error;
        } else {
                mutex_lock(&input->mutex);
                if (input->users)
@@ -873,15 +996,9 @@ 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;
        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)
-                               disable_irq_wake(bdata->irq);
-                       bdata->suspended = false;
-               }
+               gpio_keys_disable_wakeup(ddata);
        } else {
                mutex_lock(&input->mutex);
                if (input->users)

diff --git a/include/dt-bindings/input/gpio-keys.h b/include/dt-bindings/input/gpio-keys.h
new file mode 100644 (file)
index 0000000..8962df7
--- /dev/null
+++ b/include/dt-bindings/input/gpio-keys.h
@@ -0,0 +1,13 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * This header provides constants for gpio keys bindings.
+ */
+
+#ifndef _DT_BINDINGS_GPIO_KEYS_H
+#define _DT_BINDINGS_GPIO_KEYS_H
+
+#define EV_ACT_ANY             0x00    /* asserted or deasserted */
+#define EV_ACT_ASSERTED                0x01    /* asserted */
+#define EV_ACT_DEASSERTED      0x02    /* deasserted */
+
+#endif /* _DT_BINDINGS_GPIO_KEYS_H */

diff --git a/include/linux/gpio_keys.h b/include/linux/gpio_keys.h
index d06bf77400f16ae861b938696dae9f2b93d797f9..7160df54a6fe3e6fef2c6be9dd67698e185beace 100644 (file)
--- a/include/linux/gpio_keys.h
+++ b/include/linux/gpio_keys.h
@@ -13,6 +13,7 @@ struct device;
  * @desc:              label that will be attached to button's gpio
  * @type:              input event type (%EV_KEY, %EV_SW, %EV_ABS)
  * @wakeup:            configure the button as a wake-up source
+ * @wakeup_event_action:       event action to trigger wakeup
  * @debounce_interval: debounce ticks interval in msecs
  * @can_disable:       %true indicates that userspace is allowed to
  *                     disable button via sysfs
@@ -26,6 +27,7 @@ struct gpio_keys_button {
        const char *desc;
        unsigned int type;
        int wakeup;
+       int wakeup_event_action;
        int debounce_interval;
        bool can_disable;
        int value;