Input: matrix_keypad - add support for clustered irq

This one adds support of a combined irq source for the whole matrix keypad.
This can be useful if all rows and columns of the keypad are e.g. connected
to a GPIO expander, which only has one interrupt line for all events on
every single GPIO.

Signed-off-by: Luotao Fu <l.fu@pengutronix.de>
Acked-by: Eric Miao <eric.y.miao@gmail.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

2 files changed, 86 insertions, 28 deletions

diff --git a/drivers/input/keyboard/matrix_keypad.c b/drivers/input/keyboard/matrix_keypad.c
index b443e088fd3c..b02e4268e18f 100644
--- a/drivers/input/keyboard/matrix_keypad.c
+++ b/drivers/input/keyboard/matrix_keypad.c
@@ -37,6 +37,7 @@ struct matrix_keypad {
         spinlock_t lock;
         bool scan_pending;
         bool stopped;
+        bool gpio_all_disabled;
 };
 
 /*
@@ -87,8 +88,12 @@ static void enable_row_irqs(struct matrix_keypad *keypad)
         const struct matrix_keypad_platform_data *pdata = keypad->pdata;
         int i;
 
-        for (i = 0; i < pdata->num_row_gpios; i++)
-                enable_irq(gpio_to_irq(pdata->row_gpios[i]));
+        if (pdata->clustered_irq > 0)
+                enable_irq(pdata->clustered_irq);
+        else {
+                for (i = 0; i < pdata->num_row_gpios; i++)
+                        enable_irq(gpio_to_irq(pdata->row_gpios[i]));
+        }
 }
 
 static void disable_row_irqs(struct matrix_keypad *keypad)
@@ -96,8 +101,12 @@ static void disable_row_irqs(struct matrix_keypad *keypad)
         const struct matrix_keypad_platform_data *pdata = keypad->pdata;
         int i;
 
-        for (i = 0; i < pdata->num_row_gpios; i++)
-                disable_irq_nosync(gpio_to_irq(pdata->row_gpios[i]));
+        if (pdata->clustered_irq > 0)
+                disable_irq_nosync(pdata->clustered_irq);
+        else {
+                for (i = 0; i < pdata->num_row_gpios; i++)
+                        disable_irq_nosync(gpio_to_irq(pdata->row_gpios[i]));
+        }
 }
 
 /*
@@ -216,45 +225,69 @@ static void matrix_keypad_stop(struct input_dev *dev)
 }
 
 #ifdef CONFIG_PM
-static int matrix_keypad_suspend(struct device *dev)
+static void matrix_keypad_enable_wakeup(struct matrix_keypad *keypad)
 {
-        struct platform_device *pdev = to_platform_device(dev);
-        struct matrix_keypad *keypad = platform_get_drvdata(pdev);
         const struct matrix_keypad_platform_data *pdata = keypad->pdata;
+        unsigned int gpio;
         int i;
 
-        matrix_keypad_stop(keypad->input_dev);
+        if (pdata->clustered_irq > 0) {
+                if (enable_irq_wake(pdata->clustered_irq) == 0)
+                        keypad->gpio_all_disabled = true;
+        } else {
 
-        if (device_may_wakeup(&pdev->dev)) {
                 for (i = 0; i < pdata->num_row_gpios; i++) {
                         if (!test_bit(i, keypad->disabled_gpios)) {
-                                unsigned int gpio = pdata->row_gpios[i];
+                                gpio = pdata->row_gpios[i];
 
                                 if (enable_irq_wake(gpio_to_irq(gpio)) == 0)
                                         __set_bit(i, keypad->disabled_gpios);
                         }
                 }
         }
-
-        return 0;
 }
 
-static int matrix_keypad_resume(struct device *dev)
+static void matrix_keypad_disable_wakeup(struct matrix_keypad *keypad)
 {
-        struct platform_device *pdev = to_platform_device(dev);
-        struct matrix_keypad *keypad = platform_get_drvdata(pdev);
         const struct matrix_keypad_platform_data *pdata = keypad->pdata;
+        unsigned int gpio;
         int i;
 
-        if (device_may_wakeup(&pdev->dev)) {
+        if (pdata->clustered_irq > 0) {
+                if (keypad->gpio_all_disabled) {
+                        disable_irq_wake(pdata->clustered_irq);
+                        keypad->gpio_all_disabled = false;
+                }
+        } else {
                 for (i = 0; i < pdata->num_row_gpios; i++) {
                         if (test_and_clear_bit(i, keypad->disabled_gpios)) {
-                                unsigned int gpio = pdata->row_gpios[i];
-
+                                gpio = pdata->row_gpios[i];
                                 disable_irq_wake(gpio_to_irq(gpio));
                         }
                 }
         }
+}
+
+static int matrix_keypad_suspend(struct device *dev)
+{
+        struct platform_device *pdev = to_platform_device(dev);
+        struct matrix_keypad *keypad = platform_get_drvdata(pdev);
+
+        matrix_keypad_stop(keypad->input_dev);
+
+        if (device_may_wakeup(&pdev->dev))
+                matrix_keypad_enable_wakeup(keypad);
+
+        return 0;
+}
+
+static int matrix_keypad_resume(struct device *dev)
+{
+        struct platform_device *pdev = to_platform_device(dev);
+        struct matrix_keypad *keypad = platform_get_drvdata(pdev);
+
+        if (device_may_wakeup(&pdev->dev))
+                matrix_keypad_disable_wakeup(keypad);
 
         matrix_keypad_start(keypad->input_dev);
 
@@ -296,17 +329,31 @@ static int __devinit init_matrix_gpio(struct platform_device *pdev,
                 gpio_direction_input(pdata->row_gpios[i]);
         }
 
-        for (i = 0; i < pdata->num_row_gpios; i++) {
-                err = request_irq(gpio_to_irq(pdata->row_gpios[i]),
+        if (pdata->clustered_irq > 0) {
+                err = request_irq(pdata->clustered_irq,
                                 matrix_keypad_interrupt,
-                                IRQF_DISABLED |
-                                IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
+                                pdata->clustered_irq_flags,
                                 "matrix-keypad", keypad);
                 if (err) {
                         dev_err(&pdev->dev,
-                                "Unable to acquire interrupt for GPIO line %i\n",
-                                pdata->row_gpios[i]);
-                        goto err_free_irqs;
+                                "Unable to acquire clustered interrupt\n");
+                        goto err_free_rows;
+                }
+        } else {
+                for (i = 0; i < pdata->num_row_gpios; i++) {
+                        err = request_irq(gpio_to_irq(pdata->row_gpios[i]),
+                                        matrix_keypad_interrupt,
+                                        IRQF_DISABLED |
+                                        IRQF_TRIGGER_RISING |
+                                        IRQF_TRIGGER_FALLING,
+                                        "matrix-keypad", keypad);
+                        if (err) {
+                                dev_err(&pdev->dev,
+                                        "Unable to acquire interrupt "
+                                        "for GPIO line %i\n",
+                                        pdata->row_gpios[i]);
+                                goto err_free_irqs;
+                        }
                 }
         }
 
@@ -418,11 +465,16 @@ static int __devexit matrix_keypad_remove(struct platform_device *pdev)
 
         device_init_wakeup(&pdev->dev, 0);
 
-        for (i = 0; i < pdata->num_row_gpios; i++) {
-                free_irq(gpio_to_irq(pdata->row_gpios[i]), keypad);
-                gpio_free(pdata->row_gpios[i]);
+        if (pdata->clustered_irq > 0) {
+                free_irq(pdata->clustered_irq, keypad);
+        } else {
+                for (i = 0; i < pdata->num_row_gpios; i++)
+                        free_irq(gpio_to_irq(pdata->row_gpios[i]), keypad);
         }
 
+        for (i = 0; i < pdata->num_row_gpios; i++)
+                gpio_free(pdata->row_gpios[i]);
+
         for (i = 0; i < pdata->num_col_gpios; i++)
                 gpio_free(pdata->col_gpios[i]);
 
diff --git a/include/linux/input/matrix_keypad.h b/include/linux/input/matrix_keypad.h
index c964cd7f436a..80352ad6581a 100644
--- a/include/linux/input/matrix_keypad.h
+++ b/include/linux/input/matrix_keypad.h
@@ -41,6 +41,9 @@ struct matrix_keymap_data {
  * @col_scan_delay_us: delay, measured in microseconds, that is
  *      needed before we can keypad after activating column gpio
  * @debounce_ms: debounce interval in milliseconds
+ * @clustered_irq: may be specified if interrupts of all row/column GPIOs
+ *      are bundled to one single irq
+ * @clustered_irq_flags: flags that are needed for the clustered irq
  * @active_low: gpio polarity
  * @wakeup: controls whether the device should be set up as wakeup
  *      source
@@ -63,6 +66,9 @@ struct matrix_keypad_platform_data {
         /* key debounce interval in milli-second */
         unsigned int    debounce_ms;
 
+        unsigned int    clustered_irq;
+        unsigned int    clustered_irq_flags;
+
         bool            active_low;
         bool            wakeup;
         bool            no_autorepeat;