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v3.15
  1/*
  2 *  Copyright (C) 2010, Lars-Peter Clausen <lars@metafoo.de>
  3 *  PWM beeper driver
  4 *
  5 *  This program is free software; you can redistribute it and/or modify it
  6 *  under  the terms of the GNU General  Public License as published by the
  7 *  Free Software Foundation;  either version 2 of the License, or (at your
  8 *  option) any later version.
  9 *
 10 *  You should have received a copy of the GNU General Public License along
 11 *  with this program; if not, write to the Free Software Foundation, Inc.,
 12 *  675 Mass Ave, Cambridge, MA 02139, USA.
 13 *
 14 */
 15
 16#include <linux/input.h>
 17#include <linux/module.h>
 18#include <linux/kernel.h>
 19#include <linux/of.h>
 20#include <linux/platform_device.h>
 21#include <linux/pwm.h>
 22#include <linux/slab.h>
 23
 24struct pwm_beeper {
 25	struct input_dev *input;
 26	struct pwm_device *pwm;
 27	unsigned long period;
 28};
 29
 30#define HZ_TO_NANOSECONDS(x) (1000000000UL/(x))
 31
 32static int pwm_beeper_event(struct input_dev *input,
 33			    unsigned int type, unsigned int code, int value)
 34{
 35	int ret = 0;
 36	struct pwm_beeper *beeper = input_get_drvdata(input);
 37	unsigned long period;
 38
 39	if (type != EV_SND || value < 0)
 40		return -EINVAL;
 41
 42	switch (code) {
 43	case SND_BELL:
 44		value = value ? 1000 : 0;
 45		break;
 46	case SND_TONE:
 47		break;
 48	default:
 49		return -EINVAL;
 50	}
 51
 52	if (value == 0) {
 53		pwm_config(beeper->pwm, 0, 0);
 54		pwm_disable(beeper->pwm);
 55	} else {
 56		period = HZ_TO_NANOSECONDS(value);
 57		ret = pwm_config(beeper->pwm, period / 2, period);
 58		if (ret)
 59			return ret;
 60		ret = pwm_enable(beeper->pwm);
 61		if (ret)
 62			return ret;
 63		beeper->period = period;
 64	}
 65
 66	return 0;
 67}
 68
 69static int pwm_beeper_probe(struct platform_device *pdev)
 70{
 71	unsigned long pwm_id = (unsigned long)dev_get_platdata(&pdev->dev);
 72	struct pwm_beeper *beeper;
 73	int error;
 74
 75	beeper = kzalloc(sizeof(*beeper), GFP_KERNEL);
 76	if (!beeper)
 77		return -ENOMEM;
 78
 79	beeper->pwm = pwm_get(&pdev->dev, NULL);
 80	if (IS_ERR(beeper->pwm)) {
 81		dev_dbg(&pdev->dev, "unable to request PWM, trying legacy API\n");
 82		beeper->pwm = pwm_request(pwm_id, "pwm beeper");
 83	}
 84
 85	if (IS_ERR(beeper->pwm)) {
 86		error = PTR_ERR(beeper->pwm);
 87		dev_err(&pdev->dev, "Failed to request pwm device: %d\n", error);
 88		goto err_free;
 89	}
 90
 91	beeper->input = input_allocate_device();
 92	if (!beeper->input) {
 93		dev_err(&pdev->dev, "Failed to allocate input device\n");
 94		error = -ENOMEM;
 95		goto err_pwm_free;
 96	}
 97	beeper->input->dev.parent = &pdev->dev;
 98
 99	beeper->input->name = "pwm-beeper";
100	beeper->input->phys = "pwm/input0";
101	beeper->input->id.bustype = BUS_HOST;
102	beeper->input->id.vendor = 0x001f;
103	beeper->input->id.product = 0x0001;
104	beeper->input->id.version = 0x0100;
105
106	beeper->input->evbit[0] = BIT(EV_SND);
107	beeper->input->sndbit[0] = BIT(SND_TONE) | BIT(SND_BELL);
108
109	beeper->input->event = pwm_beeper_event;
110
111	input_set_drvdata(beeper->input, beeper);
112
113	error = input_register_device(beeper->input);
114	if (error) {
115		dev_err(&pdev->dev, "Failed to register input device: %d\n", error);
116		goto err_input_free;
117	}
118
119	platform_set_drvdata(pdev, beeper);
120
121	return 0;
122
123err_input_free:
124	input_free_device(beeper->input);
125err_pwm_free:
126	pwm_free(beeper->pwm);
127err_free:
128	kfree(beeper);
129
130	return error;
131}
132
133static int pwm_beeper_remove(struct platform_device *pdev)
134{
135	struct pwm_beeper *beeper = platform_get_drvdata(pdev);
136
137	input_unregister_device(beeper->input);
138
139	pwm_disable(beeper->pwm);
140	pwm_free(beeper->pwm);
141
142	kfree(beeper);
143
144	return 0;
145}
146
147#ifdef CONFIG_PM_SLEEP
148static int pwm_beeper_suspend(struct device *dev)
149{
150	struct pwm_beeper *beeper = dev_get_drvdata(dev);
151
152	if (beeper->period)
153		pwm_disable(beeper->pwm);
154
155	return 0;
156}
157
158static int pwm_beeper_resume(struct device *dev)
159{
160	struct pwm_beeper *beeper = dev_get_drvdata(dev);
161
162	if (beeper->period) {
163		pwm_config(beeper->pwm, beeper->period / 2, beeper->period);
164		pwm_enable(beeper->pwm);
165	}
166
167	return 0;
168}
169
170static SIMPLE_DEV_PM_OPS(pwm_beeper_pm_ops,
171			 pwm_beeper_suspend, pwm_beeper_resume);
172
173#define PWM_BEEPER_PM_OPS (&pwm_beeper_pm_ops)
174#else
175#define PWM_BEEPER_PM_OPS NULL
176#endif
177
178#ifdef CONFIG_OF
179static const struct of_device_id pwm_beeper_match[] = {
180	{ .compatible = "pwm-beeper", },
181	{ },
182};
 
183#endif
184
185static struct platform_driver pwm_beeper_driver = {
186	.probe	= pwm_beeper_probe,
187	.remove = pwm_beeper_remove,
188	.driver = {
189		.name	= "pwm-beeper",
190		.owner	= THIS_MODULE,
191		.pm	= PWM_BEEPER_PM_OPS,
192		.of_match_table = of_match_ptr(pwm_beeper_match),
193	},
194};
195module_platform_driver(pwm_beeper_driver);
196
197MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
198MODULE_DESCRIPTION("PWM beeper driver");
199MODULE_LICENSE("GPL");
200MODULE_ALIAS("platform:pwm-beeper");
v4.6
  1/*
  2 *  Copyright (C) 2010, Lars-Peter Clausen <lars@metafoo.de>
  3 *  PWM beeper driver
  4 *
  5 *  This program is free software; you can redistribute it and/or modify it
  6 *  under  the terms of the GNU General  Public License as published by the
  7 *  Free Software Foundation;  either version 2 of the License, or (at your
  8 *  option) any later version.
  9 *
 10 *  You should have received a copy of the GNU General Public License along
 11 *  with this program; if not, write to the Free Software Foundation, Inc.,
 12 *  675 Mass Ave, Cambridge, MA 02139, USA.
 13 *
 14 */
 15
 16#include <linux/input.h>
 17#include <linux/module.h>
 18#include <linux/kernel.h>
 19#include <linux/of.h>
 20#include <linux/platform_device.h>
 21#include <linux/pwm.h>
 22#include <linux/slab.h>
 23
 24struct pwm_beeper {
 25	struct input_dev *input;
 26	struct pwm_device *pwm;
 27	unsigned long period;
 28};
 29
 30#define HZ_TO_NANOSECONDS(x) (1000000000UL/(x))
 31
 32static int pwm_beeper_event(struct input_dev *input,
 33			    unsigned int type, unsigned int code, int value)
 34{
 35	int ret = 0;
 36	struct pwm_beeper *beeper = input_get_drvdata(input);
 37	unsigned long period;
 38
 39	if (type != EV_SND || value < 0)
 40		return -EINVAL;
 41
 42	switch (code) {
 43	case SND_BELL:
 44		value = value ? 1000 : 0;
 45		break;
 46	case SND_TONE:
 47		break;
 48	default:
 49		return -EINVAL;
 50	}
 51
 52	if (value == 0) {
 
 53		pwm_disable(beeper->pwm);
 54	} else {
 55		period = HZ_TO_NANOSECONDS(value);
 56		ret = pwm_config(beeper->pwm, period / 2, period);
 57		if (ret)
 58			return ret;
 59		ret = pwm_enable(beeper->pwm);
 60		if (ret)
 61			return ret;
 62		beeper->period = period;
 63	}
 64
 65	return 0;
 66}
 67
 68static int pwm_beeper_probe(struct platform_device *pdev)
 69{
 70	unsigned long pwm_id = (unsigned long)dev_get_platdata(&pdev->dev);
 71	struct pwm_beeper *beeper;
 72	int error;
 73
 74	beeper = kzalloc(sizeof(*beeper), GFP_KERNEL);
 75	if (!beeper)
 76		return -ENOMEM;
 77
 78	beeper->pwm = pwm_get(&pdev->dev, NULL);
 79	if (IS_ERR(beeper->pwm)) {
 80		dev_dbg(&pdev->dev, "unable to request PWM, trying legacy API\n");
 81		beeper->pwm = pwm_request(pwm_id, "pwm beeper");
 82	}
 83
 84	if (IS_ERR(beeper->pwm)) {
 85		error = PTR_ERR(beeper->pwm);
 86		dev_err(&pdev->dev, "Failed to request pwm device: %d\n", error);
 87		goto err_free;
 88	}
 89
 90	beeper->input = input_allocate_device();
 91	if (!beeper->input) {
 92		dev_err(&pdev->dev, "Failed to allocate input device\n");
 93		error = -ENOMEM;
 94		goto err_pwm_free;
 95	}
 96	beeper->input->dev.parent = &pdev->dev;
 97
 98	beeper->input->name = "pwm-beeper";
 99	beeper->input->phys = "pwm/input0";
100	beeper->input->id.bustype = BUS_HOST;
101	beeper->input->id.vendor = 0x001f;
102	beeper->input->id.product = 0x0001;
103	beeper->input->id.version = 0x0100;
104
105	beeper->input->evbit[0] = BIT(EV_SND);
106	beeper->input->sndbit[0] = BIT(SND_TONE) | BIT(SND_BELL);
107
108	beeper->input->event = pwm_beeper_event;
109
110	input_set_drvdata(beeper->input, beeper);
111
112	error = input_register_device(beeper->input);
113	if (error) {
114		dev_err(&pdev->dev, "Failed to register input device: %d\n", error);
115		goto err_input_free;
116	}
117
118	platform_set_drvdata(pdev, beeper);
119
120	return 0;
121
122err_input_free:
123	input_free_device(beeper->input);
124err_pwm_free:
125	pwm_free(beeper->pwm);
126err_free:
127	kfree(beeper);
128
129	return error;
130}
131
132static int pwm_beeper_remove(struct platform_device *pdev)
133{
134	struct pwm_beeper *beeper = platform_get_drvdata(pdev);
135
136	input_unregister_device(beeper->input);
137
138	pwm_disable(beeper->pwm);
139	pwm_free(beeper->pwm);
140
141	kfree(beeper);
142
143	return 0;
144}
145
146static int __maybe_unused pwm_beeper_suspend(struct device *dev)
 
147{
148	struct pwm_beeper *beeper = dev_get_drvdata(dev);
149
150	if (beeper->period)
151		pwm_disable(beeper->pwm);
152
153	return 0;
154}
155
156static int __maybe_unused pwm_beeper_resume(struct device *dev)
157{
158	struct pwm_beeper *beeper = dev_get_drvdata(dev);
159
160	if (beeper->period) {
161		pwm_config(beeper->pwm, beeper->period / 2, beeper->period);
162		pwm_enable(beeper->pwm);
163	}
164
165	return 0;
166}
167
168static SIMPLE_DEV_PM_OPS(pwm_beeper_pm_ops,
169			 pwm_beeper_suspend, pwm_beeper_resume);
170
 
 
 
 
 
171#ifdef CONFIG_OF
172static const struct of_device_id pwm_beeper_match[] = {
173	{ .compatible = "pwm-beeper", },
174	{ },
175};
176MODULE_DEVICE_TABLE(of, pwm_beeper_match);
177#endif
178
179static struct platform_driver pwm_beeper_driver = {
180	.probe	= pwm_beeper_probe,
181	.remove = pwm_beeper_remove,
182	.driver = {
183		.name	= "pwm-beeper",
184		.pm	= &pwm_beeper_pm_ops,
 
185		.of_match_table = of_match_ptr(pwm_beeper_match),
186	},
187};
188module_platform_driver(pwm_beeper_driver);
189
190MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
191MODULE_DESCRIPTION("PWM beeper driver");
192MODULE_LICENSE("GPL");
193MODULE_ALIAS("platform:pwm-beeper");