diff options
Diffstat (limited to 'drivers/input/misc/pwm-beeper.c')
| -rw-r--r-- | drivers/input/misc/pwm-beeper.c | 192 |
1 files changed, 192 insertions, 0 deletions
diff --git a/drivers/input/misc/pwm-beeper.c b/drivers/input/misc/pwm-beeper.c new file mode 100644 index 000000000..e82edf810 --- /dev/null +++ b/drivers/input/misc/pwm-beeper.c @@ -0,0 +1,192 @@ +/* + * Copyright (C) 2010, Lars-Peter Clausen <lars@metafoo.de> + * PWM beeper driver + * + * 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. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 675 Mass Ave, Cambridge, MA 02139, USA. + * + */ + +#include <linux/input.h> +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/pwm.h> +#include <linux/slab.h> + +struct pwm_beeper { + struct input_dev *input; + struct pwm_device *pwm; + unsigned long period; +}; + +#define HZ_TO_NANOSECONDS(x) (1000000000UL/(x)) + +static int pwm_beeper_event(struct input_dev *input, + unsigned int type, unsigned int code, int value) +{ + int ret = 0; + struct pwm_beeper *beeper = input_get_drvdata(input); + unsigned long period; + + if (type != EV_SND || value < 0) + return -EINVAL; + + switch (code) { + case SND_BELL: + value = value ? 1000 : 0; + break; + case SND_TONE: + break; + default: + return -EINVAL; + } + + if (value == 0) { + pwm_disable(beeper->pwm); + } else { + period = HZ_TO_NANOSECONDS(value); + ret = pwm_config(beeper->pwm, period / 2, period); + if (ret) + return ret; + ret = pwm_enable(beeper->pwm); + if (ret) + return ret; + beeper->period = period; + } + + return 0; +} + +static int pwm_beeper_probe(struct platform_device *pdev) +{ + unsigned long pwm_id = (unsigned long)dev_get_platdata(&pdev->dev); + struct pwm_beeper *beeper; + int error; + + beeper = kzalloc(sizeof(*beeper), GFP_KERNEL); + if (!beeper) + return -ENOMEM; + + beeper->pwm = pwm_get(&pdev->dev, NULL); + if (IS_ERR(beeper->pwm)) { + dev_dbg(&pdev->dev, "unable to request PWM, trying legacy API\n"); + beeper->pwm = pwm_request(pwm_id, "pwm beeper"); + } + + if (IS_ERR(beeper->pwm)) { + error = PTR_ERR(beeper->pwm); + dev_err(&pdev->dev, "Failed to request pwm device: %d\n", error); + goto err_free; + } + + beeper->input = input_allocate_device(); + if (!beeper->input) { + dev_err(&pdev->dev, "Failed to allocate input device\n"); + error = -ENOMEM; + goto err_pwm_free; + } + beeper->input->dev.parent = &pdev->dev; + + beeper->input->name = "pwm-beeper"; + beeper->input->phys = "pwm/input0"; + beeper->input->id.bustype = BUS_HOST; + beeper->input->id.vendor = 0x001f; + beeper->input->id.product = 0x0001; + beeper->input->id.version = 0x0100; + + beeper->input->evbit[0] = BIT(EV_SND); + beeper->input->sndbit[0] = BIT(SND_TONE) | BIT(SND_BELL); + + beeper->input->event = pwm_beeper_event; + + input_set_drvdata(beeper->input, beeper); + + error = input_register_device(beeper->input); + if (error) { + dev_err(&pdev->dev, "Failed to register input device: %d\n", error); + goto err_input_free; + } + + platform_set_drvdata(pdev, beeper); + + return 0; + +err_input_free: + input_free_device(beeper->input); +err_pwm_free: + pwm_free(beeper->pwm); +err_free: + kfree(beeper); + + return error; +} + +static int pwm_beeper_remove(struct platform_device *pdev) +{ + struct pwm_beeper *beeper = platform_get_drvdata(pdev); + + input_unregister_device(beeper->input); + + pwm_disable(beeper->pwm); + pwm_free(beeper->pwm); + + kfree(beeper); + + return 0; +} + +static int __maybe_unused pwm_beeper_suspend(struct device *dev) +{ + struct pwm_beeper *beeper = dev_get_drvdata(dev); + + if (beeper->period) + pwm_disable(beeper->pwm); + + return 0; +} + +static int __maybe_unused pwm_beeper_resume(struct device *dev) +{ + struct pwm_beeper *beeper = dev_get_drvdata(dev); + + if (beeper->period) { + pwm_config(beeper->pwm, beeper->period / 2, beeper->period); + pwm_enable(beeper->pwm); + } + + return 0; +} + +static SIMPLE_DEV_PM_OPS(pwm_beeper_pm_ops, + pwm_beeper_suspend, pwm_beeper_resume); + +#ifdef CONFIG_OF +static const struct of_device_id pwm_beeper_match[] = { + { .compatible = "pwm-beeper", }, + { }, +}; +#endif + +static struct platform_driver pwm_beeper_driver = { + .probe = pwm_beeper_probe, + .remove = pwm_beeper_remove, + .driver = { + .name = "pwm-beeper", + .pm = &pwm_beeper_pm_ops, + .of_match_table = of_match_ptr(pwm_beeper_match), + }, +}; +module_platform_driver(pwm_beeper_driver); + +MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>"); +MODULE_DESCRIPTION("PWM beeper driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:pwm-beeper"); |