1 /* 2 * LED Class Core 3 * 4 * Copyright 2005-2006 Openedhand Ltd. 5 * 6 * Author: 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/kernel.h> 15 #include <linux/list.h> 16 #include <linux/module.h> 17 #include <linux/rwsem.h> 18 #include <linux/leds.h> 19 #include "leds.h" 20 21 DECLARE_RWSEM(leds_list_lock); 22 EXPORT_SYMBOL_GPL(leds_list_lock); 23 24 LIST_HEAD(leds_list); 25 EXPORT_SYMBOL_GPL(leds_list); 26 27 static void led_set_software_blink(struct led_classdev *led_cdev, 28 unsigned long delay_on, 29 unsigned long delay_off) 30 { 31 int current_brightness; 32 33 current_brightness = led_get_brightness(led_cdev); 34 if (current_brightness) 35 led_cdev->blink_brightness = current_brightness; 36 if (!led_cdev->blink_brightness) 37 led_cdev->blink_brightness = led_cdev->max_brightness; 38 39 led_cdev->blink_delay_on = delay_on; 40 led_cdev->blink_delay_off = delay_off; 41 42 /* never on - don't blink */ 43 if (!delay_on) 44 return; 45 46 /* never off - just set to brightness */ 47 if (!delay_off) { 48 __led_set_brightness(led_cdev, led_cdev->blink_brightness); 49 return; 50 } 51 52 mod_timer(&led_cdev->blink_timer, jiffies + 1); 53 } 54 55 56 static void led_blink_setup(struct led_classdev *led_cdev, 57 unsigned long *delay_on, 58 unsigned long *delay_off) 59 { 60 if (!(led_cdev->flags & LED_BLINK_ONESHOT) && 61 led_cdev->blink_set && 62 !led_cdev->blink_set(led_cdev, delay_on, delay_off)) 63 return; 64 65 /* blink with 1 Hz as default if nothing specified */ 66 if (!*delay_on && !*delay_off) 67 *delay_on = *delay_off = 500; 68 69 led_set_software_blink(led_cdev, *delay_on, *delay_off); 70 } 71 72 void led_blink_set(struct led_classdev *led_cdev, 73 unsigned long *delay_on, 74 unsigned long *delay_off) 75 { 76 del_timer_sync(&led_cdev->blink_timer); 77 78 led_cdev->flags &= ~LED_BLINK_ONESHOT; 79 led_cdev->flags &= ~LED_BLINK_ONESHOT_STOP; 80 81 led_blink_setup(led_cdev, delay_on, delay_off); 82 } 83 EXPORT_SYMBOL(led_blink_set); 84 85 void led_blink_set_oneshot(struct led_classdev *led_cdev, 86 unsigned long *delay_on, 87 unsigned long *delay_off, 88 int invert) 89 { 90 if ((led_cdev->flags & LED_BLINK_ONESHOT) && 91 timer_pending(&led_cdev->blink_timer)) 92 return; 93 94 led_cdev->flags |= LED_BLINK_ONESHOT; 95 led_cdev->flags &= ~LED_BLINK_ONESHOT_STOP; 96 97 if (invert) 98 led_cdev->flags |= LED_BLINK_INVERT; 99 else 100 led_cdev->flags &= ~LED_BLINK_INVERT; 101 102 led_blink_setup(led_cdev, delay_on, delay_off); 103 } 104 EXPORT_SYMBOL(led_blink_set_oneshot); 105 106 void led_set_brightness(struct led_classdev *led_cdev, 107 enum led_brightness brightness) 108 { 109 /* stop and clear soft-blink timer */ 110 del_timer_sync(&led_cdev->blink_timer); 111 led_cdev->blink_delay_on = 0; 112 led_cdev->blink_delay_off = 0; 113 114 __led_set_brightness(led_cdev, brightness); 115 } 116 EXPORT_SYMBOL(led_set_brightness); 117