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