1 #include <linux/kernel.h> 2 #include <linux/module.h> 3 #include <linux/init.h> 4 #include <linux/proc_fs.h> 5 #include <linux/string.h> 6 #include <linux/jiffies.h> 7 #include <linux/timer.h> 8 #include <linux/uaccess.h> 9 10 #include <asm/auxio.h> 11 12 #define LED_MAX_LENGTH 8 /* maximum chars written to proc file */ 13 14 static inline void led_toggle(void) 15 { 16 unsigned char val = get_auxio(); 17 unsigned char on, off; 18 19 if (val & AUXIO_LED) { 20 on = 0; 21 off = AUXIO_LED; 22 } else { 23 on = AUXIO_LED; 24 off = 0; 25 } 26 27 set_auxio(on, off); 28 } 29 30 static struct timer_list led_blink_timer; 31 32 static void led_blink(unsigned long timeout) 33 { 34 led_toggle(); 35 36 /* reschedule */ 37 if (!timeout) { /* blink according to load */ 38 led_blink_timer.expires = jiffies + 39 ((1 + (avenrun[0] >> FSHIFT)) * HZ); 40 led_blink_timer.data = 0; 41 } else { /* blink at user specified interval */ 42 led_blink_timer.expires = jiffies + (timeout * HZ); 43 led_blink_timer.data = timeout; 44 } 45 add_timer(&led_blink_timer); 46 } 47 48 static int led_read_proc(char *buf, char **start, off_t offset, int count, 49 int *eof, void *data) 50 { 51 int len = 0; 52 53 if (get_auxio() & AUXIO_LED) 54 len = sprintf(buf, "on\n"); 55 else 56 len = sprintf(buf, "off\n"); 57 58 return len; 59 } 60 61 static int led_write_proc(struct file *file, const char __user *buffer, 62 unsigned long count, void *data) 63 { 64 char *buf = NULL; 65 66 if (count > LED_MAX_LENGTH) 67 count = LED_MAX_LENGTH; 68 69 buf = kmalloc(sizeof(char) * (count + 1), GFP_KERNEL); 70 if (!buf) 71 return -ENOMEM; 72 73 if (copy_from_user(buf, buffer, count)) { 74 kfree(buf); 75 return -EFAULT; 76 } 77 78 buf[count] = '\0'; 79 80 /* work around \n when echo'ing into proc */ 81 if (buf[count - 1] == '\n') 82 buf[count - 1] = '\0'; 83 84 /* before we change anything we want to stop any running timers, 85 * otherwise calls such as on will have no persistent effect 86 */ 87 del_timer_sync(&led_blink_timer); 88 89 if (!strcmp(buf, "on")) { 90 auxio_set_led(AUXIO_LED_ON); 91 } else if (!strcmp(buf, "toggle")) { 92 led_toggle(); 93 } else if ((*buf > '0') && (*buf <= '9')) { 94 led_blink(simple_strtoul(buf, NULL, 10)); 95 } else if (!strcmp(buf, "load")) { 96 led_blink(0); 97 } else { 98 auxio_set_led(AUXIO_LED_OFF); 99 } 100 101 kfree(buf); 102 103 return count; 104 } 105 106 static struct proc_dir_entry *led; 107 108 #define LED_VERSION "0.1" 109 110 static int __init led_init(void) 111 { 112 init_timer(&led_blink_timer); 113 led_blink_timer.function = led_blink; 114 115 led = create_proc_entry("led", 0, NULL); 116 if (!led) 117 return -ENOMEM; 118 119 led->read_proc = led_read_proc; /* reader function */ 120 led->write_proc = led_write_proc; /* writer function */ 121 led->owner = THIS_MODULE; 122 123 printk(KERN_INFO 124 "led: version %s, Lars Kotthoff <metalhead@metalhead.ws>\n", 125 LED_VERSION); 126 127 return 0; 128 } 129 130 static void __exit led_exit(void) 131 { 132 remove_proc_entry("led", NULL); 133 del_timer_sync(&led_blink_timer); 134 } 135 136 module_init(led_init); 137 module_exit(led_exit); 138 139 MODULE_AUTHOR("Lars Kotthoff <metalhead@metalhead.ws>"); 140 MODULE_DESCRIPTION("Provides control of the front LED on SPARC systems."); 141 MODULE_LICENSE("GPL"); 142 MODULE_VERSION(LED_VERSION); 143