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v3.1
  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/platform_device.h>
 20#include <linux/pwm.h>
 21#include <linux/slab.h>
 22
 23struct pwm_beeper {
 24	struct input_dev *input;
 25	struct pwm_device *pwm;
 26	unsigned long period;
 27};
 28
 29#define HZ_TO_NANOSECONDS(x) (1000000000UL/(x))
 30
 31static int pwm_beeper_event(struct input_dev *input,
 32			    unsigned int type, unsigned int code, int value)
 33{
 34	int ret = 0;
 35	struct pwm_beeper *beeper = input_get_drvdata(input);
 36	unsigned long period;
 37
 38	if (type != EV_SND || value < 0)
 39		return -EINVAL;
 40
 41	switch (code) {
 42	case SND_BELL:
 43		value = value ? 1000 : 0;
 44		break;
 45	case SND_TONE:
 46		break;
 47	default:
 48		return -EINVAL;
 49	}
 50
 51	if (value == 0) {
 52		pwm_config(beeper->pwm, 0, 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 __devinit pwm_beeper_probe(struct platform_device *pdev)
 69{
 70	unsigned long pwm_id = (unsigned long)pdev->dev.platform_data;
 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_request(pwm_id, "pwm beeper");
 
 
 
 
 79
 80	if (IS_ERR(beeper->pwm)) {
 81		error = PTR_ERR(beeper->pwm);
 82		dev_err(&pdev->dev, "Failed to request pwm device: %d\n", error);
 83		goto err_free;
 84	}
 85
 86	beeper->input = input_allocate_device();
 87	if (!beeper->input) {
 88		dev_err(&pdev->dev, "Failed to allocate input device\n");
 89		error = -ENOMEM;
 90		goto err_pwm_free;
 91	}
 92	beeper->input->dev.parent = &pdev->dev;
 93
 94	beeper->input->name = "pwm-beeper";
 95	beeper->input->phys = "pwm/input0";
 96	beeper->input->id.bustype = BUS_HOST;
 97	beeper->input->id.vendor = 0x001f;
 98	beeper->input->id.product = 0x0001;
 99	beeper->input->id.version = 0x0100;
100
101	beeper->input->evbit[0] = BIT(EV_SND);
102	beeper->input->sndbit[0] = BIT(SND_TONE) | BIT(SND_BELL);
103
104	beeper->input->event = pwm_beeper_event;
105
106	input_set_drvdata(beeper->input, beeper);
107
108	error = input_register_device(beeper->input);
109	if (error) {
110		dev_err(&pdev->dev, "Failed to register input device: %d\n", error);
111		goto err_input_free;
112	}
113
114	platform_set_drvdata(pdev, beeper);
115
116	return 0;
117
118err_input_free:
119	input_free_device(beeper->input);
120err_pwm_free:
121	pwm_free(beeper->pwm);
122err_free:
123	kfree(beeper);
124
125	return error;
126}
127
128static int __devexit pwm_beeper_remove(struct platform_device *pdev)
129{
130	struct pwm_beeper *beeper = platform_get_drvdata(pdev);
131
132	platform_set_drvdata(pdev, NULL);
133	input_unregister_device(beeper->input);
134
135	pwm_disable(beeper->pwm);
136	pwm_free(beeper->pwm);
137
138	kfree(beeper);
139
140	return 0;
141}
142
143#ifdef CONFIG_PM
144static int pwm_beeper_suspend(struct device *dev)
145{
146	struct pwm_beeper *beeper = dev_get_drvdata(dev);
147
148	if (beeper->period)
149		pwm_disable(beeper->pwm);
150
151	return 0;
152}
153
154static int pwm_beeper_resume(struct device *dev)
155{
156	struct pwm_beeper *beeper = dev_get_drvdata(dev);
157
158	if (beeper->period) {
159		pwm_config(beeper->pwm, beeper->period / 2, beeper->period);
160		pwm_enable(beeper->pwm);
161	}
162
163	return 0;
164}
165
166static SIMPLE_DEV_PM_OPS(pwm_beeper_pm_ops,
167			 pwm_beeper_suspend, pwm_beeper_resume);
168
169#define PWM_BEEPER_PM_OPS (&pwm_beeper_pm_ops)
170#else
171#define PWM_BEEPER_PM_OPS NULL
 
 
 
172#endif
173
174static struct platform_driver pwm_beeper_driver = {
175	.probe	= pwm_beeper_probe,
176	.remove = __devexit_p(pwm_beeper_remove),
177	.driver = {
178		.name	= "pwm-beeper",
179		.owner	= THIS_MODULE,
180		.pm	= PWM_BEEPER_PM_OPS,
181	},
182};
183
184static int __init pwm_beeper_init(void)
185{
186	return platform_driver_register(&pwm_beeper_driver);
187}
188module_init(pwm_beeper_init);
189
190static void __exit pwm_beeper_exit(void)
191{
192	platform_driver_unregister(&pwm_beeper_driver);
193}
194module_exit(pwm_beeper_exit);
195
196MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
197MODULE_DESCRIPTION("PWM beeper driver");
198MODULE_LICENSE("GPL");
199MODULE_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");