Version:  2.0.40 2.2.26 2.4.37 3.5 3.6 3.7 3.8 3.9 3.10 3.11 3.12 3.13 3.14 3.15 3.16 3.17 3.18 3.19 4.0 4.1

Linux/drivers/input/misc/pwm-beeper.c

  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 
 24 struct 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 
 32 static 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 
 68 static 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 
122 err_input_free:
123         input_free_device(beeper->input);
124 err_pwm_free:
125         pwm_free(beeper->pwm);
126 err_free:
127         kfree(beeper);
128 
129         return error;
130 }
131 
132 static 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 
146 static 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 
156 static 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 
168 static SIMPLE_DEV_PM_OPS(pwm_beeper_pm_ops,
169                          pwm_beeper_suspend, pwm_beeper_resume);
170 
171 #ifdef CONFIG_OF
172 static const struct of_device_id pwm_beeper_match[] = {
173         { .compatible = "pwm-beeper", },
174         { },
175 };
176 #endif
177 
178 static struct platform_driver pwm_beeper_driver = {
179         .probe  = pwm_beeper_probe,
180         .remove = pwm_beeper_remove,
181         .driver = {
182                 .name   = "pwm-beeper",
183                 .pm     = &pwm_beeper_pm_ops,
184                 .of_match_table = of_match_ptr(pwm_beeper_match),
185         },
186 };
187 module_platform_driver(pwm_beeper_driver);
188 
189 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
190 MODULE_DESCRIPTION("PWM beeper driver");
191 MODULE_LICENSE("GPL");
192 MODULE_ALIAS("platform:pwm-beeper");
193 

This page was automatically generated by LXR 0.3.1 (source).  •  Linux is a registered trademark of Linus Torvalds  •  Contact us