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