[PATCH V2] matrix_keypad: add support for clustered irq

From: Luotao Fu
Date: Thu May 27 2010 - 02:44:14 EST


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@xxxxxxxxxxxxxx>
---
V2 Changes:
* create separate functions for suspend/resume calls.
* add bool flag to signal enable/disable state of all gpios.
* add spinlock to suspend and resume callbacks.

drivers/input/keyboard/matrix_keypad.c | 138 ++++++++++++++++++++++++--------
include/linux/input/matrix_keypad.h | 5 +
2 files changed, 109 insertions(+), 34 deletions(-)

diff --git a/drivers/input/keyboard/matrix_keypad.c b/drivers/input/keyboard/matrix_keypad.c
index b443e08..99b7204 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]));
+ }
}

/*
@@ -216,25 +225,74 @@ static void matrix_keypad_stop(struct input_dev *dev)
}

#ifdef CONFIG_PM
-static int matrix_keypad_suspend(struct device *dev)
+static inline void __suspend_keypad(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 cirq = pdata->clustered_irq;
+ unsigned int gpio;
+ unsigned long flags;
int i;

- matrix_keypad_stop(keypad->input_dev);
+ spin_lock_irqsave(&keypad->lock, flags);

- 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];
+ if (pdata->clustered_irq > 0) {
+ if (enable_irq_wake(cirq) == 0)
+ keypad->gpio_all_disabled = true;

- if (enable_irq_wake(gpio_to_irq(gpio)) == 0)
- __set_bit(i, keypad->disabled_gpios);
- }
+ goto out;
+ }
+
+ for (i = 0; i < pdata->num_row_gpios; i++) {
+ if (!test_bit(i, keypad->disabled_gpios)) {
+ gpio = pdata->row_gpios[i];
+
+ if (enable_irq_wake(gpio_to_irq(gpio)) == 0)
+ __set_bit(i, keypad->disabled_gpios);
+ }
+ }
+out:
+ spin_unlock_irqrestore(&keypad->lock, flags);
+}
+
+static inline void __resume_keypad(struct matrix_keypad *keypad)
+{
+ const struct matrix_keypad_platform_data *pdata = keypad->pdata;
+ unsigned int cirq = pdata->clustered_irq;
+ unsigned int gpio;
+ unsigned long flags;
+ int i;
+
+ spin_lock_irqsave(&keypad->lock, flags);
+
+ if (pdata->clustered_irq > 0) {
+ if (keypad->gpio_all_disabled) {
+ disable_irq_wake(cirq);
+ keypad->gpio_all_disabled = false;
+ }
+
+ goto out;
+ }
+
+ for (i = 0; i < pdata->num_row_gpios; i++) {
+ if (test_and_clear_bit(i, keypad->disabled_gpios)) {
+ gpio = pdata->row_gpios[i];
+ disable_irq_wake(gpio_to_irq(gpio));
}
}
+out:
+ spin_unlock_irqrestore(&keypad->lock, flags);
+
+}
+
+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))
+ __suspend_keypad(keypad);

return 0;
}
@@ -246,15 +304,8 @@ static int matrix_keypad_resume(struct device *dev)
const struct matrix_keypad_platform_data *pdata = keypad->pdata;
int i;

- if (device_may_wakeup(&pdev->dev)) {
- 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];
-
- disable_irq_wake(gpio_to_irq(gpio));
- }
- }
- }
+ if (device_may_wakeup(&pdev->dev))
+ __resume_keypad(keypad);

matrix_keypad_start(keypad->input_dev);

@@ -296,17 +347,31 @@ 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 +483,16 @@ 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 c964cd7..8e8dc2e 100644
--- a/include/linux/input/matrix_keypad.h
+++ b/include/linux/input/matrix_keypad.h
@@ -63,6 +63,11 @@ struct matrix_keypad_platform_data {
/* key debounce interval in milli-second */
unsigned int debounce_ms;

+ /* used if interrupts of all row/column GPIOs are bundled to one single
+ * irq */
+ unsigned int clustered_irq;
+ unsigned int clustered_irq_flags;
+
bool active_low;
bool wakeup;
bool no_autorepeat;
--
1.7.0

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