diff options
Diffstat (limited to 'drivers/input/keyboard/gpio_keys.c')
| -rw-r--r-- | drivers/input/keyboard/gpio_keys.c | 276 |
1 files changed, 276 insertions, 0 deletions
diff --git a/drivers/input/keyboard/gpio_keys.c b/drivers/input/keyboard/gpio_keys.c new file mode 100644 index 0000000..05f3f43 --- /dev/null +++ b/drivers/input/keyboard/gpio_keys.c @@ -0,0 +1,276 @@ +/* + * Driver for keys on GPIO lines capable of generating interrupts. + * + * Copyright 2005 Phil Blundell + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/module.h> + +#include <linux/init.h> +#include <linux/fs.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/sched.h> +#include <linux/pm.h> +#include <linux/sysctl.h> +#include <linux/proc_fs.h> +#include <linux/delay.h> +#include <linux/platform_device.h> +#include <linux/input.h> +#include <linux/gpio_keys.h> + +#include <asm/gpio.h> + +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_button_data *bdata) +{ + struct gpio_keys_button *button = bdata->button; + struct input_dev *input = bdata->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); +} + +static irqreturn_t gpio_keys_isr(int irq, void *dev_id) +{ + struct gpio_button_data *bdata = dev_id; + struct gpio_keys_button *button = bdata->button; + + BUG_ON(irq != gpio_to_irq(button->gpio)); + + if (button->debounce_interval) + mod_timer(&bdata->timer, + jiffies + msecs_to_jiffies(button->debounce_interval)); + else + gpio_keys_report_event(bdata); + + return IRQ_HANDLED; +} + +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 (!ddata || !input) { + error = -ENOMEM; + goto fail1; + } + + platform_set_drvdata(pdev, ddata); + + input->name = pdev->name; + input->phys = "gpio-keys/input0"; + input->dev.parent = &pdev->dev; + + input->id.bustype = BUS_HOST; + input->id.vendor = 0x0001; + 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; + bdata->button = button; + 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 fail2; + } + + error = gpio_direction_input(button->gpio); + if (error < 0) { + pr_err("gpio-keys: failed to configure input" + " direction for GPIO %d, error %d\n", + button->gpio, error); + gpio_free(button->gpio); + goto fail2; + } + + irq = gpio_to_irq(button->gpio); + if (irq < 0) { + error = irq; + pr_err("gpio-keys: Unable to get irq number" + " for GPIO %d, error %d\n", + button->gpio, error); + gpio_free(button->gpio); + goto fail2; + } + + error = request_irq(irq, gpio_keys_isr, + IRQF_SAMPLE_RANDOM | IRQF_TRIGGER_RISING | + IRQF_TRIGGER_FALLING, + button->desc ? button->desc : "gpio_keys", + bdata); + if (error) { + pr_err("gpio-keys: Unable to claim irq %d; error %d\n", + irq, error); + gpio_free(button->gpio); + goto fail2; + } + + if (button->wakeup) + wakeup = 1; + + input_set_capability(input, type, button->code); + } + + error = input_register_device(input); + if (error) { + pr_err("gpio-keys: Unable to register input device, " + "error: %d\n", error); + goto fail2; + } + + device_init_wakeup(&pdev->dev, wakeup); + + return 0; + + fail2: + while (--i >= 0) { + free_irq(gpio_to_irq(pdata->buttons[i].gpio), &ddata->data[i]); + 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; +} + +static int __devexit gpio_keys_remove(struct platform_device *pdev) +{ + struct gpio_keys_platform_data *pdata = pdev->dev.platform_data; + struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev); + struct input_dev *input = ddata->input; + int i; + + device_init_wakeup(&pdev->dev, 0); + + for (i = 0; i < pdata->nbuttons; i++) { + int irq = gpio_to_irq(pdata->buttons[i].gpio); + free_irq(irq, &ddata->data[i]); + if (pdata->buttons[i].debounce_interval) + del_timer_sync(&ddata->data[i].timer); + gpio_free(pdata->buttons[i].gpio); + } + + input_unregister_device(input); + + return 0; +} + + +#ifdef CONFIG_PM +static int gpio_keys_suspend(struct platform_device *pdev, pm_message_t state) +{ + struct gpio_keys_platform_data *pdata = pdev->dev.platform_data; + int i; + + if (device_may_wakeup(&pdev->dev)) { + for (i = 0; i < pdata->nbuttons; i++) { + struct gpio_keys_button *button = &pdata->buttons[i]; + if (button->wakeup) { + int irq = gpio_to_irq(button->gpio); + enable_irq_wake(irq); + } + } + } + + return 0; +} + +static int gpio_keys_resume(struct platform_device *pdev) +{ + struct gpio_keys_platform_data *pdata = pdev->dev.platform_data; + int i; + + if (device_may_wakeup(&pdev->dev)) { + for (i = 0; i < pdata->nbuttons; i++) { + struct gpio_keys_button *button = &pdata->buttons[i]; + if (button->wakeup) { + int irq = gpio_to_irq(button->gpio); + disable_irq_wake(irq); + } + } + } + + return 0; +} +#else +#define gpio_keys_suspend NULL +#define gpio_keys_resume NULL +#endif + +static struct platform_driver gpio_keys_device_driver = { + .probe = gpio_keys_probe, + .remove = __devexit_p(gpio_keys_remove), + .suspend = gpio_keys_suspend, + .resume = gpio_keys_resume, + .driver = { + .name = "gpio-keys", + .owner = THIS_MODULE, + } +}; + +static int __init gpio_keys_init(void) +{ + return platform_driver_register(&gpio_keys_device_driver); +} + +static void __exit gpio_keys_exit(void) +{ + platform_driver_unregister(&gpio_keys_device_driver); +} + +module_init(gpio_keys_init); +module_exit(gpio_keys_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Phil Blundell <pb@handhelds.org>"); +MODULE_DESCRIPTION("Keyboard driver for CPU GPIOs"); +MODULE_ALIAS("platform:gpio-keys"); |
