1 /* 2 * One-shot LED Trigger 3 * 4 * Copyright 2012, Fabio Baltieri <fabio.baltieri@gmail.com> 5 * 6 * Based on ledtrig-timer.c by Richard Purdie <rpurdie@openedhand.com> 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License version 2 as 10 * published by the Free Software Foundation. 11 * 12 */ 13 14 #include <linux/module.h> 15 #include <linux/kernel.h> 16 #include <linux/init.h> 17 #include <linux/device.h> 18 #include <linux/ctype.h> 19 #include <linux/slab.h> 20 #include <linux/leds.h> 21 #include "../leds.h" 22 23 #define DEFAULT_DELAY 100 24 25 struct oneshot_trig_data { 26 unsigned int invert; 27 }; 28 29 static ssize_t led_shot(struct device *dev, 30 struct device_attribute *attr, const char *buf, size_t size) 31 { 32 struct led_classdev *led_cdev = dev_get_drvdata(dev); 33 struct oneshot_trig_data *oneshot_data = led_cdev->trigger_data; 34 35 led_blink_set_oneshot(led_cdev, 36 &led_cdev->blink_delay_on, &led_cdev->blink_delay_off, 37 oneshot_data->invert); 38 39 /* content is ignored */ 40 return size; 41 } 42 static ssize_t led_invert_show(struct device *dev, 43 struct device_attribute *attr, char *buf) 44 { 45 struct led_classdev *led_cdev = dev_get_drvdata(dev); 46 struct oneshot_trig_data *oneshot_data = led_cdev->trigger_data; 47 48 return sprintf(buf, "%u\n", oneshot_data->invert); 49 } 50 51 static ssize_t led_invert_store(struct device *dev, 52 struct device_attribute *attr, const char *buf, size_t size) 53 { 54 struct led_classdev *led_cdev = dev_get_drvdata(dev); 55 struct oneshot_trig_data *oneshot_data = led_cdev->trigger_data; 56 unsigned long state; 57 int ret; 58 59 ret = kstrtoul(buf, 0, &state); 60 if (ret) 61 return ret; 62 63 oneshot_data->invert = !!state; 64 65 if (oneshot_data->invert) 66 __led_set_brightness(led_cdev, LED_FULL); 67 else 68 __led_set_brightness(led_cdev, LED_OFF); 69 70 return size; 71 } 72 73 static ssize_t led_delay_on_show(struct device *dev, 74 struct device_attribute *attr, char *buf) 75 { 76 struct led_classdev *led_cdev = dev_get_drvdata(dev); 77 78 return sprintf(buf, "%lu\n", led_cdev->blink_delay_on); 79 } 80 81 static ssize_t led_delay_on_store(struct device *dev, 82 struct device_attribute *attr, const char *buf, size_t size) 83 { 84 struct led_classdev *led_cdev = dev_get_drvdata(dev); 85 unsigned long state; 86 int ret; 87 88 ret = kstrtoul(buf, 0, &state); 89 if (ret) 90 return ret; 91 92 led_cdev->blink_delay_on = state; 93 94 return size; 95 } 96 static ssize_t led_delay_off_show(struct device *dev, 97 struct device_attribute *attr, char *buf) 98 { 99 struct led_classdev *led_cdev = dev_get_drvdata(dev); 100 101 return sprintf(buf, "%lu\n", led_cdev->blink_delay_off); 102 } 103 104 static ssize_t led_delay_off_store(struct device *dev, 105 struct device_attribute *attr, const char *buf, size_t size) 106 { 107 struct led_classdev *led_cdev = dev_get_drvdata(dev); 108 unsigned long state; 109 int ret; 110 111 ret = kstrtoul(buf, 0, &state); 112 if (ret) 113 return ret; 114 115 led_cdev->blink_delay_off = state; 116 117 return size; 118 } 119 120 static DEVICE_ATTR(delay_on, 0644, led_delay_on_show, led_delay_on_store); 121 static DEVICE_ATTR(delay_off, 0644, led_delay_off_show, led_delay_off_store); 122 static DEVICE_ATTR(invert, 0644, led_invert_show, led_invert_store); 123 static DEVICE_ATTR(shot, 0200, NULL, led_shot); 124 125 static void oneshot_trig_activate(struct led_classdev *led_cdev) 126 { 127 struct oneshot_trig_data *oneshot_data; 128 int rc; 129 130 oneshot_data = kzalloc(sizeof(*oneshot_data), GFP_KERNEL); 131 if (!oneshot_data) 132 return; 133 134 led_cdev->trigger_data = oneshot_data; 135 136 rc = device_create_file(led_cdev->dev, &dev_attr_delay_on); 137 if (rc) 138 goto err_out_trig_data; 139 rc = device_create_file(led_cdev->dev, &dev_attr_delay_off); 140 if (rc) 141 goto err_out_delayon; 142 rc = device_create_file(led_cdev->dev, &dev_attr_invert); 143 if (rc) 144 goto err_out_delayoff; 145 rc = device_create_file(led_cdev->dev, &dev_attr_shot); 146 if (rc) 147 goto err_out_invert; 148 149 led_cdev->blink_delay_on = DEFAULT_DELAY; 150 led_cdev->blink_delay_off = DEFAULT_DELAY; 151 152 led_cdev->activated = true; 153 154 return; 155 156 err_out_invert: 157 device_remove_file(led_cdev->dev, &dev_attr_invert); 158 err_out_delayoff: 159 device_remove_file(led_cdev->dev, &dev_attr_delay_off); 160 err_out_delayon: 161 device_remove_file(led_cdev->dev, &dev_attr_delay_on); 162 err_out_trig_data: 163 kfree(led_cdev->trigger_data); 164 } 165 166 static void oneshot_trig_deactivate(struct led_classdev *led_cdev) 167 { 168 struct oneshot_trig_data *oneshot_data = led_cdev->trigger_data; 169 170 if (led_cdev->activated) { 171 device_remove_file(led_cdev->dev, &dev_attr_delay_on); 172 device_remove_file(led_cdev->dev, &dev_attr_delay_off); 173 device_remove_file(led_cdev->dev, &dev_attr_invert); 174 device_remove_file(led_cdev->dev, &dev_attr_shot); 175 kfree(oneshot_data); 176 led_cdev->activated = false; 177 } 178 179 /* Stop blinking */ 180 led_set_brightness(led_cdev, LED_OFF); 181 } 182 183 static struct led_trigger oneshot_led_trigger = { 184 .name = "oneshot", 185 .activate = oneshot_trig_activate, 186 .deactivate = oneshot_trig_deactivate, 187 }; 188 189 static int __init oneshot_trig_init(void) 190 { 191 return led_trigger_register(&oneshot_led_trigger); 192 } 193 194 static void __exit oneshot_trig_exit(void) 195 { 196 led_trigger_unregister(&oneshot_led_trigger); 197 } 198 199 module_init(oneshot_trig_init); 200 module_exit(oneshot_trig_exit); 201 202 MODULE_AUTHOR("Fabio Baltieri <fabio.baltieri@gmail.com>"); 203 MODULE_DESCRIPTION("One-shot LED trigger"); 204 MODULE_LICENSE("GPL"); 205