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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 | /* * 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/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_config(beeper->pwm, 0, 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)pdev->dev.platform_data; 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; } #ifdef CONFIG_PM_SLEEP static int 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 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); #define PWM_BEEPER_PM_OPS (&pwm_beeper_pm_ops) #else #define PWM_BEEPER_PM_OPS NULL #endif #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", .owner = THIS_MODULE, .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"); |