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>

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;
 
+	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;
 
+	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);
 
@@ -296,19 +329,33 @@ static int __devinit init_matrix_gpio(struct platform_device *pdev,
 		gpio_direction_input(pdata->row_gpios[i]);
 	}
 
+	if (pdata->clustered_irq > 0) {
+		err = request_irq(pdata->clustered_irq,
+				matrix_keypad_interrupt,
+				pdata->clustered_irq_flags,
+				"matrix-keypad", keypad);
+		if (err) {
+			dev_err(&pdev->dev,
+				"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,
+					IRQF_TRIGGER_RISING |
+					IRQF_TRIGGER_FALLING,
 					"matrix-keypad", keypad);
 			if (err) {
 				dev_err(&pdev->dev,
-				"Unable to acquire interrupt for GPIO line %i\n",
+					"Unable to acquire interrupt "
+					"for GPIO line %i\n",
 					pdata->row_gpios[i]);
 				goto err_free_irqs;
 			}
 		}
+	}
 
 	/* initialized as disabled - enabled by input->open */
 	disable_row_irqs(keypad);
@@ -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++) {
+	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);
-		gpio_free(pdata->row_gpios[i]);
 	}
 
+	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]);
 

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;