1 #include <linux/kernel.h> 2 #include <linux/module.h> 3 #include <linux/init.h> 4 #include <linux/proc_fs.h> 5 #include <linux/seq_file.h> 6 #include <linux/slab.h> 7 #include <linux/string.h> 8 #include <linux/jiffies.h> 9 #include <linux/timer.h> 10 #include <linux/uaccess.h> 11 12 #include <asm/auxio.h> 13 14 #define LED_MAX_LENGTH 8 /* maximum chars written to proc file */ 15 16 static inline void led_toggle(void) 17 { 18 unsigned char val = get_auxio(); 19 unsigned char on, off; 20 21 if (val & AUXIO_LED) { 22 on = 0; 23 off = AUXIO_LED; 24 } else { 25 on = AUXIO_LED; 26 off = 0; 27 } 28 29 set_auxio(on, off); 30 } 31 32 static struct timer_list led_blink_timer; 33 34 static void led_blink(unsigned long timeout) 35 { 36 led_toggle(); 37 38 /* reschedule */ 39 if (!timeout) { /* blink according to load */ 40 led_blink_timer.expires = jiffies + 41 ((1 + (avenrun[0] >> FSHIFT)) * HZ); 42 led_blink_timer.data = 0; 43 } else { /* blink at user specified interval */ 44 led_blink_timer.expires = jiffies + (timeout * HZ); 45 led_blink_timer.data = timeout; 46 } 47 add_timer(&led_blink_timer); 48 } 49 50 static int led_proc_show(struct seq_file *m, void *v) 51 { 52 if (get_auxio() & AUXIO_LED) 53 seq_puts(m, "on\n"); 54 else 55 seq_puts(m, "off\n"); 56 return 0; 57 } 58 59 static int led_proc_open(struct inode *inode, struct file *file) 60 { 61 return single_open(file, led_proc_show, NULL); 62 } 63 64 static ssize_t led_proc_write(struct file *file, const char __user *buffer, 65 size_t count, loff_t *ppos) 66 { 67 char *buf = NULL; 68 69 if (count > LED_MAX_LENGTH) 70 count = LED_MAX_LENGTH; 71 72 buf = kmalloc(sizeof(char) * (count + 1), GFP_KERNEL); 73 if (!buf) 74 return -ENOMEM; 75 76 if (copy_from_user(buf, buffer, count)) { 77 kfree(buf); 78 return -EFAULT; 79 } 80 81 buf[count] = '\0'; 82 83 /* work around \n when echo'ing into proc */ 84 if (buf[count - 1] == '\n') 85 buf[count - 1] = '\0'; 86 87 /* before we change anything we want to stop any running timers, 88 * otherwise calls such as on will have no persistent effect 89 */ 90 del_timer_sync(&led_blink_timer); 91 92 if (!strcmp(buf, "on")) { 93 auxio_set_led(AUXIO_LED_ON); 94 } else if (!strcmp(buf, "toggle")) { 95 led_toggle(); 96 } else if ((*buf > '0') && (*buf <= '9')) { 97 led_blink(simple_strtoul(buf, NULL, 10)); 98 } else if (!strcmp(buf, "load")) { 99 led_blink(0); 100 } else { 101 auxio_set_led(AUXIO_LED_OFF); 102 } 103 104 kfree(buf); 105 106 return count; 107 } 108 109 static const struct file_operations led_proc_fops = { 110 .owner = THIS_MODULE, 111 .open = led_proc_open, 112 .read = seq_read, 113 .llseek = seq_lseek, 114 .release = single_release, 115 .write = led_proc_write, 116 }; 117 118 static struct proc_dir_entry *led; 119 120 #define LED_VERSION "0.1" 121 122 static int __init led_init(void) 123 { 124 init_timer(&led_blink_timer); 125 led_blink_timer.function = led_blink; 126 127 led = proc_create("led", 0, NULL, &led_proc_fops); 128 if (!led) 129 return -ENOMEM; 130 131 printk(KERN_INFO 132 "led: version %s, Lars Kotthoff <metalhead@metalhead.ws>\n", 133 LED_VERSION); 134 135 return 0; 136 } 137 138 static void __exit led_exit(void) 139 { 140 remove_proc_entry("led", NULL); 141 del_timer_sync(&led_blink_timer); 142 } 143 144 module_init(led_init); 145 module_exit(led_exit); 146 147 MODULE_AUTHOR("Lars Kotthoff <metalhead@metalhead.ws>"); 148 MODULE_DESCRIPTION("Provides control of the front LED on SPARC systems."); 149 MODULE_LICENSE("GPL"); 150 MODULE_VERSION(LED_VERSION); 151