diff options
Diffstat (limited to 'drivers/input/misc/gpio-beeper.c')
-rw-r--r-- | drivers/input/misc/gpio-beeper.c | 127 |
1 files changed, 127 insertions, 0 deletions
diff --git a/drivers/input/misc/gpio-beeper.c b/drivers/input/misc/gpio-beeper.c new file mode 100644 index 00000000000..b757435e2b3 --- /dev/null +++ b/drivers/input/misc/gpio-beeper.c @@ -0,0 +1,127 @@ +/* + * Generic GPIO beeper driver + * + * Copyright (C) 2013 Alexander Shiyan <shc_work@mail.ru> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ + +#include <linux/input.h> +#include <linux/module.h> +#include <linux/of_gpio.h> +#include <linux/workqueue.h> +#include <linux/platform_device.h> + +#define BEEPER_MODNAME "gpio-beeper" + +struct gpio_beeper { + struct work_struct work; + int gpio; + bool active_low; + bool beeping; +}; + +static void gpio_beeper_toggle(struct gpio_beeper *beep, bool on) +{ + gpio_set_value_cansleep(beep->gpio, on ^ beep->active_low); +} + +static void gpio_beeper_work(struct work_struct *work) +{ + struct gpio_beeper *beep = container_of(work, struct gpio_beeper, work); + + gpio_beeper_toggle(beep, beep->beeping); +} + +static int gpio_beeper_event(struct input_dev *dev, unsigned int type, + unsigned int code, int value) +{ + struct gpio_beeper *beep = input_get_drvdata(dev); + + if (type != EV_SND || code != SND_BELL) + return -ENOTSUPP; + + if (value < 0) + return -EINVAL; + + beep->beeping = value; + /* Schedule work to actually turn the beeper on or off */ + schedule_work(&beep->work); + + return 0; +} + +static void gpio_beeper_close(struct input_dev *input) +{ + struct gpio_beeper *beep = input_get_drvdata(input); + + cancel_work_sync(&beep->work); + gpio_beeper_toggle(beep, false); +} + +static int gpio_beeper_probe(struct platform_device *pdev) +{ + struct gpio_beeper *beep; + enum of_gpio_flags flags; + struct input_dev *input; + unsigned long gflags; + int err; + + beep = devm_kzalloc(&pdev->dev, sizeof(*beep), GFP_KERNEL); + if (!beep) + return -ENOMEM; + + beep->gpio = of_get_gpio_flags(pdev->dev.of_node, 0, &flags); + if (!gpio_is_valid(beep->gpio)) + return beep->gpio; + + input = devm_input_allocate_device(&pdev->dev); + if (!input) + return -ENOMEM; + + INIT_WORK(&beep->work, gpio_beeper_work); + + input->name = pdev->name; + input->id.bustype = BUS_HOST; + input->id.vendor = 0x0001; + input->id.product = 0x0001; + input->id.version = 0x0100; + input->close = gpio_beeper_close; + input->event = gpio_beeper_event; + + input_set_capability(input, EV_SND, SND_BELL); + + beep->active_low = flags & OF_GPIO_ACTIVE_LOW; + gflags = beep->active_low ? GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW; + + err = devm_gpio_request_one(&pdev->dev, beep->gpio, gflags, pdev->name); + if (err) + return err; + + input_set_drvdata(input, beep); + + return input_register_device(input); +} + +static struct of_device_id gpio_beeper_of_match[] = { + { .compatible = BEEPER_MODNAME, }, + { } +}; +MODULE_DEVICE_TABLE(of, gpio_beeper_of_match); + +static struct platform_driver gpio_beeper_platform_driver = { + .driver = { + .name = BEEPER_MODNAME, + .owner = THIS_MODULE, + .of_match_table = gpio_beeper_of_match, + }, + .probe = gpio_beeper_probe, +}; +module_platform_driver(gpio_beeper_platform_driver); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Alexander Shiyan <shc_work@mail.ru>"); +MODULE_DESCRIPTION("Generic GPIO beeper driver"); |