From a33466e31213cd7c46696160d3db78680b58f6a3 Mon Sep 17 00:00:00 2001 From: Dmitry Baryshkov Date: Wed, 7 May 2008 16:30:15 -0400 Subject: Input: gpio-keys debouncing support Signed-off-by: Dmitry Baryshkov Signed-off-by: Dmitry Torokhov --- drivers/input/keyboard/gpio_keys.c | 89 +++++++++++++++++++++++++++++--------- include/linux/gpio_keys.h | 1 + 2 files changed, 70 insertions(+), 20 deletions(-) diff --git a/drivers/input/keyboard/gpio_keys.c b/drivers/input/keyboard/gpio_keys.c index bbd00c3fe98..be58730e636 100644 --- a/drivers/input/keyboard/gpio_keys.c +++ b/drivers/input/keyboard/gpio_keys.c @@ -26,23 +26,54 @@ #include +struct gpio_button_data { + struct gpio_keys_button *button; + struct input_dev *input; + struct timer_list timer; +}; + +struct gpio_keys_drvdata { + struct input_dev *input; + struct gpio_button_data data[0]; +}; + +static void gpio_keys_report_event(struct gpio_keys_button *button, + struct input_dev *input) +{ + unsigned int type = button->type ?: EV_KEY; + int state = (gpio_get_value(button->gpio) ? 1 : 0) ^ button->active_low; + + input_event(input, type, button->code, !!state); + input_sync(input); +} + +static void gpio_check_button(unsigned long _data) +{ + struct gpio_button_data *data = (struct gpio_button_data *)_data; + + gpio_keys_report_event(data->button, data->input); +} + static irqreturn_t gpio_keys_isr(int irq, void *dev_id) { - int i; struct platform_device *pdev = dev_id; struct gpio_keys_platform_data *pdata = pdev->dev.platform_data; - struct input_dev *input = platform_get_drvdata(pdev); + struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev); + int i; for (i = 0; i < pdata->nbuttons; i++) { struct gpio_keys_button *button = &pdata->buttons[i]; - int gpio = button->gpio; - if (irq == gpio_to_irq(gpio)) { - unsigned int type = button->type ?: EV_KEY; - int state = (gpio_get_value(gpio) ? 1 : 0) ^ button->active_low; + if (irq == gpio_to_irq(button->gpio)) { + struct gpio_button_data *bdata = &ddata->data[i]; + + if (button->debounce_interval) + mod_timer(&bdata->timer, + jiffies + + msecs_to_jiffies(button->debounce_interval)); + else + gpio_keys_report_event(button, bdata->input); - input_event(input, type, button->code, !!state); - input_sync(input); return IRQ_HANDLED; } } @@ -53,17 +84,21 @@ static irqreturn_t gpio_keys_isr(int irq, void *dev_id) static int __devinit gpio_keys_probe(struct platform_device *pdev) { struct gpio_keys_platform_data *pdata = pdev->dev.platform_data; + struct gpio_keys_drvdata *ddata; struct input_dev *input; int i, error; int wakeup = 0; + ddata = kzalloc(sizeof(struct gpio_keys_drvdata) + + pdata->nbuttons * sizeof(struct gpio_button_data), + GFP_KERNEL); input = input_allocate_device(); - if (!input) - return -ENOMEM; - - platform_set_drvdata(pdev, input); + if (!ddata || !input) { + error = -ENOMEM; + goto fail1; + } - input->evbit[0] = BIT_MASK(EV_KEY); + platform_set_drvdata(pdev, ddata); input->name = pdev->name; input->phys = "gpio-keys/input0"; @@ -74,16 +109,23 @@ static int __devinit gpio_keys_probe(struct platform_device *pdev) input->id.product = 0x0001; input->id.version = 0x0100; + ddata->input = input; + for (i = 0; i < pdata->nbuttons; i++) { struct gpio_keys_button *button = &pdata->buttons[i]; + struct gpio_button_data *bdata = &ddata->data[i]; int irq; unsigned int type = button->type ?: EV_KEY; + bdata->input = input; + setup_timer(&bdata->timer, + gpio_check_button, (unsigned long)bdata); + error = gpio_request(button->gpio, button->desc ?: "gpio_keys"); if (error < 0) { pr_err("gpio-keys: failed to request GPIO %d," " error %d\n", button->gpio, error); - goto fail; + goto fail2; } error = gpio_direction_input(button->gpio); @@ -92,7 +134,7 @@ static int __devinit gpio_keys_probe(struct platform_device *pdev) " direction for GPIO %d, error %d\n", button->gpio, error); gpio_free(button->gpio); - goto fail; + goto fail2; } irq = gpio_to_irq(button->gpio); @@ -102,7 +144,7 @@ static int __devinit gpio_keys_probe(struct platform_device *pdev) " for GPIO %d, error %d\n", button->gpio, error); gpio_free(button->gpio); - goto fail; + goto fail2; } error = request_irq(irq, gpio_keys_isr, @@ -114,7 +156,7 @@ static int __devinit gpio_keys_probe(struct platform_device *pdev) pr_err("gpio-keys: Unable to claim irq %d; error %d\n", irq, error); gpio_free(button->gpio); - goto fail; + goto fail2; } if (button->wakeup) @@ -127,21 +169,25 @@ static int __devinit gpio_keys_probe(struct platform_device *pdev) if (error) { pr_err("gpio-keys: Unable to register input device, " "error: %d\n", error); - goto fail; + goto fail2; } device_init_wakeup(&pdev->dev, wakeup); return 0; - fail: + fail2: while (--i >= 0) { free_irq(gpio_to_irq(pdata->buttons[i].gpio), pdev); + if (pdata->buttons[i].debounce_interval) + del_timer_sync(&ddata->data[i].timer); gpio_free(pdata->buttons[i].gpio); } platform_set_drvdata(pdev, NULL); + fail1: input_free_device(input); + kfree(ddata); return error; } @@ -149,7 +195,8 @@ static int __devinit gpio_keys_probe(struct platform_device *pdev) static int __devexit gpio_keys_remove(struct platform_device *pdev) { struct gpio_keys_platform_data *pdata = pdev->dev.platform_data; - struct input_dev *input = platform_get_drvdata(pdev); + struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev); + struct input_dev *input = ddata->input; int i; device_init_wakeup(&pdev->dev, 0); @@ -157,6 +204,8 @@ static int __devexit gpio_keys_remove(struct platform_device *pdev) for (i = 0; i < pdata->nbuttons; i++) { int irq = gpio_to_irq(pdata->buttons[i].gpio); free_irq(irq, pdev); + if (pdata->buttons[i].debounce_interval) + del_timer_sync(&ddata->data[i].timer); gpio_free(pdata->buttons[i].gpio); } diff --git a/include/linux/gpio_keys.h b/include/linux/gpio_keys.h index c6d3a9de563..ec6ecd74781 100644 --- a/include/linux/gpio_keys.h +++ b/include/linux/gpio_keys.h @@ -9,6 +9,7 @@ struct gpio_keys_button { char *desc; int type; /* input event type (EV_KEY, EV_SW) */ int wakeup; /* configure the button as a wake-up source */ + int debounce_interval; /* debounce ticks interval in msecs */ }; struct gpio_keys_platform_data { -- cgit v1.2.3