ledtrig-oneshot.c 4.7 KB

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  1. // SPDX-License-Identifier: GPL-2.0-only
  2. /*
  3. * One-shot LED Trigger
  4. *
  5. * Copyright 2012, Fabio Baltieri <[email protected]>
  6. *
  7. * Based on ledtrig-timer.c by Richard Purdie <[email protected]>
  8. */
  9. #include <linux/module.h>
  10. #include <linux/kernel.h>
  11. #include <linux/init.h>
  12. #include <linux/device.h>
  13. #include <linux/ctype.h>
  14. #include <linux/slab.h>
  15. #include <linux/leds.h>
  16. #include "../leds.h"
  17. #define DEFAULT_DELAY 100
  18. struct oneshot_trig_data {
  19. unsigned int invert;
  20. };
  21. static ssize_t led_shot(struct device *dev,
  22. struct device_attribute *attr, const char *buf, size_t size)
  23. {
  24. struct led_classdev *led_cdev = led_trigger_get_led(dev);
  25. struct oneshot_trig_data *oneshot_data = led_trigger_get_drvdata(dev);
  26. led_blink_set_oneshot(led_cdev,
  27. &led_cdev->blink_delay_on, &led_cdev->blink_delay_off,
  28. oneshot_data->invert);
  29. /* content is ignored */
  30. return size;
  31. }
  32. static ssize_t led_invert_show(struct device *dev,
  33. struct device_attribute *attr, char *buf)
  34. {
  35. struct oneshot_trig_data *oneshot_data = led_trigger_get_drvdata(dev);
  36. return sprintf(buf, "%u\n", oneshot_data->invert);
  37. }
  38. static ssize_t led_invert_store(struct device *dev,
  39. struct device_attribute *attr, const char *buf, size_t size)
  40. {
  41. struct led_classdev *led_cdev = led_trigger_get_led(dev);
  42. struct oneshot_trig_data *oneshot_data = led_trigger_get_drvdata(dev);
  43. unsigned long state;
  44. int ret;
  45. ret = kstrtoul(buf, 0, &state);
  46. if (ret)
  47. return ret;
  48. oneshot_data->invert = !!state;
  49. if (oneshot_data->invert)
  50. led_set_brightness_nosleep(led_cdev, LED_FULL);
  51. else
  52. led_set_brightness_nosleep(led_cdev, LED_OFF);
  53. return size;
  54. }
  55. static ssize_t led_delay_on_show(struct device *dev,
  56. struct device_attribute *attr, char *buf)
  57. {
  58. struct led_classdev *led_cdev = led_trigger_get_led(dev);
  59. return sprintf(buf, "%lu\n", led_cdev->blink_delay_on);
  60. }
  61. static ssize_t led_delay_on_store(struct device *dev,
  62. struct device_attribute *attr, const char *buf, size_t size)
  63. {
  64. struct led_classdev *led_cdev = led_trigger_get_led(dev);
  65. unsigned long state;
  66. int ret;
  67. ret = kstrtoul(buf, 0, &state);
  68. if (ret)
  69. return ret;
  70. led_cdev->blink_delay_on = state;
  71. return size;
  72. }
  73. static ssize_t led_delay_off_show(struct device *dev,
  74. struct device_attribute *attr, char *buf)
  75. {
  76. struct led_classdev *led_cdev = led_trigger_get_led(dev);
  77. return sprintf(buf, "%lu\n", led_cdev->blink_delay_off);
  78. }
  79. static ssize_t led_delay_off_store(struct device *dev,
  80. struct device_attribute *attr, const char *buf, size_t size)
  81. {
  82. struct led_classdev *led_cdev = led_trigger_get_led(dev);
  83. unsigned long state;
  84. int ret;
  85. ret = kstrtoul(buf, 0, &state);
  86. if (ret)
  87. return ret;
  88. led_cdev->blink_delay_off = state;
  89. return size;
  90. }
  91. static DEVICE_ATTR(delay_on, 0644, led_delay_on_show, led_delay_on_store);
  92. static DEVICE_ATTR(delay_off, 0644, led_delay_off_show, led_delay_off_store);
  93. static DEVICE_ATTR(invert, 0644, led_invert_show, led_invert_store);
  94. static DEVICE_ATTR(shot, 0200, NULL, led_shot);
  95. static struct attribute *oneshot_trig_attrs[] = {
  96. &dev_attr_delay_on.attr,
  97. &dev_attr_delay_off.attr,
  98. &dev_attr_invert.attr,
  99. &dev_attr_shot.attr,
  100. NULL
  101. };
  102. ATTRIBUTE_GROUPS(oneshot_trig);
  103. static void pattern_init(struct led_classdev *led_cdev)
  104. {
  105. u32 *pattern;
  106. unsigned int size = 0;
  107. pattern = led_get_default_pattern(led_cdev, &size);
  108. if (!pattern)
  109. goto out_default;
  110. if (size != 2) {
  111. dev_warn(led_cdev->dev,
  112. "Expected 2 but got %u values for delays pattern\n",
  113. size);
  114. goto out_default;
  115. }
  116. led_cdev->blink_delay_on = pattern[0];
  117. led_cdev->blink_delay_off = pattern[1];
  118. kfree(pattern);
  119. return;
  120. out_default:
  121. kfree(pattern);
  122. led_cdev->blink_delay_on = DEFAULT_DELAY;
  123. led_cdev->blink_delay_off = DEFAULT_DELAY;
  124. }
  125. static int oneshot_trig_activate(struct led_classdev *led_cdev)
  126. {
  127. struct oneshot_trig_data *oneshot_data;
  128. oneshot_data = kzalloc(sizeof(*oneshot_data), GFP_KERNEL);
  129. if (!oneshot_data)
  130. return -ENOMEM;
  131. led_set_trigger_data(led_cdev, oneshot_data);
  132. if (led_cdev->flags & LED_INIT_DEFAULT_TRIGGER) {
  133. pattern_init(led_cdev);
  134. /*
  135. * Mark as initialized even on pattern_init() error because
  136. * any consecutive call to it would produce the same error.
  137. */
  138. led_cdev->flags &= ~LED_INIT_DEFAULT_TRIGGER;
  139. }
  140. return 0;
  141. }
  142. static void oneshot_trig_deactivate(struct led_classdev *led_cdev)
  143. {
  144. struct oneshot_trig_data *oneshot_data = led_get_trigger_data(led_cdev);
  145. kfree(oneshot_data);
  146. /* Stop blinking */
  147. led_set_brightness(led_cdev, LED_OFF);
  148. }
  149. static struct led_trigger oneshot_led_trigger = {
  150. .name = "oneshot",
  151. .activate = oneshot_trig_activate,
  152. .deactivate = oneshot_trig_deactivate,
  153. .groups = oneshot_trig_groups,
  154. };
  155. module_led_trigger(oneshot_led_trigger);
  156. MODULE_AUTHOR("Fabio Baltieri <[email protected]>");
  157. MODULE_DESCRIPTION("One-shot LED trigger");
  158. MODULE_LICENSE("GPL v2");