target/linux/generic-2.6/files-2.6.28/drivers/leds/ledtrig-morse.c

   1 /*
   2  *  LED Morse Trigger
   3  *
   4  *  Copyright (C) 2007 Gabor Juhos <juhosg at openwrt.org>
   5  *
   6  *  This file was based on: drivers/led/ledtrig-timer.c
   7  *      Copyright 2005-2006 Openedhand Ltd.
   8  *      Author: Richard Purdie <rpurdie@openedhand.com>
   9  *
  10  *  also based on the patch '[PATCH] 2.5.59 morse code panics' posted
  11  *  in the LKML by Tomas Szepe at Thu, 30 Jan 2003
  12  *      Copyright (C) 2002 Andrew Rodland <arodland@noln.com>
  13  *      Copyright (C) 2003 Tomas Szepe <szepe@pinerecords.com>
  14  *
  15  *  This program is free software; you can redistribute it and/or modify it
  16  *  under the terms of the GNU General Public License version 2 as published
  17  *  by the Free Software Foundation.
  18  *
  19  */
  20
  21 #include <linux/kernel.h>
  22 #include <linux/version.h>
  23 #include <linux/module.h>
  24 #include <linux/jiffies.h>
  25 #include <linux/init.h>
  26 #include <linux/list.h>
  27 #include <linux/spinlock.h>
  28 #include <linux/device.h>
  29 #include <linux/sysdev.h>
  30 #include <linux/timer.h>
  31 #include <linux/ctype.h>
  32 #include <linux/leds.h>
  33
  34 #include "leds.h"
  35
  36 #define MORSE_DELAY_BASE        (HZ/2)
  37
  38 #define MORSE_STATE_BLINK_START 0
  39 #define MORSE_STATE_BLINK_STOP  1
  40
  41 #define MORSE_DIT_LEN   1
  42 #define MORSE_DAH_LEN   3
  43 #define MORSE_SPACE_LEN 7
  44
  45 struct morse_trig_data {
  46         unsigned long delay;
  47         char *msg;
  48
  49         unsigned char morse;
  50         unsigned char state;
  51         char *msgpos;
  52         struct timer_list timer;
  53 };
  54
  55 const unsigned char morsetable[] = {
  56         0122, 0, 0310, 0, 0, 0163,                              /* "#$%&' */
  57         055, 0155, 0, 0, 0163, 0141, 0152, 0051,                /* ()*+,-./ */
  58         077, 076, 074, 070, 060, 040, 041, 043, 047, 057,       /* 0-9 */
  59         0107, 0125, 0, 0061, 0, 0114, 0,                        /* :;<=>?@ */
  60         006, 021, 025, 011, 002, 024, 013, 020, 004,            /* A-I */
  61         036, 015, 022, 007, 005, 017, 026, 033, 012,            /* J-R */
  62         010, 003, 014, 030, 016, 031, 035, 023,                 /* S-Z */
  63         0, 0, 0, 0, 0154                                        /* [\]^_ */
  64 };
  65
  66 static inline unsigned char tomorse(char c) {
  67         if (c >= 'a' && c <= 'z')
  68                 c = c - 'a' + 'A';
  69         if (c >= '"' && c <= '_') {
  70                 return morsetable[c - '"'];
  71         } else
  72                 return 0;
  73 }
  74
  75 static inline unsigned long dit_len(struct morse_trig_data *morse_data)
  76 {
  77         return MORSE_DIT_LEN*morse_data->delay;
  78 }
  79
  80 static inline unsigned long dah_len(struct morse_trig_data *morse_data)
  81 {
  82         return MORSE_DAH_LEN*morse_data->delay;
  83 }
  84
  85 static inline unsigned long space_len(struct morse_trig_data *morse_data)
  86 {
  87         return MORSE_SPACE_LEN*morse_data->delay;
  88 }
  89
  90 static void morse_timer_function(unsigned long data)
  91 {
  92         struct led_classdev *led_cdev = (struct led_classdev *)data;
  93         struct morse_trig_data *morse_data = led_cdev->trigger_data;
  94         unsigned long brightness = LED_OFF;
  95         unsigned long delay = 0;
  96
  97         if (!morse_data->msg)
  98                 goto set_led;
  99
 100         switch (morse_data->state) {
 101         case MORSE_STATE_BLINK_START:
 102                 /* Starting a new blink.  We have a valid code in morse. */
 103                 delay = (morse_data->morse & 001) ? dah_len(morse_data):
 104                         dit_len(morse_data);
 105                 brightness = LED_FULL;
 106                 morse_data->state = MORSE_STATE_BLINK_STOP;
 107                 morse_data->morse >>= 1;
 108                 break;
 109         case MORSE_STATE_BLINK_STOP:
 110                 /* Coming off of a blink. */
 111                 morse_data->state = MORSE_STATE_BLINK_START;
 112
 113                 if (morse_data->morse > 1) {
 114                         /* Not done yet, just a one-dit pause. */
 115                         delay = dit_len(morse_data);
 116                         break;
 117                 }
 118
 119                 /* Get a new char, figure out how much space. */
 120                 /* First time through */
 121                 if (!morse_data->msgpos)
 122                         morse_data->msgpos = (char *)morse_data->msg;
 123
 124                 if (!*morse_data->msgpos) {
 125                         /* Repeating */
 126                         morse_data->msgpos = (char *)morse_data->msg;
 127                         delay = space_len(morse_data);
 128                 } else {
 129                         /* Inter-letter space */
 130                         delay = dah_len(morse_data);
 131                 }
 132
 133                 if (!(morse_data->morse = tomorse(*morse_data->msgpos))) {
 134                         delay = space_len(morse_data);
 135                         /* And get us back here */
 136                         morse_data->state = MORSE_STATE_BLINK_STOP;
 137                 }
 138                 morse_data->msgpos++;
 139                 break;
 140         }
 141
 142         mod_timer(&morse_data->timer, jiffies + msecs_to_jiffies(delay));
 143
 144 set_led:
 145         led_set_brightness(led_cdev, brightness);
 146 }
 147
 148 static ssize_t _morse_delay_show(struct led_classdev *led_cdev, char *buf)
 149 {
 150         struct morse_trig_data *morse_data = led_cdev->trigger_data;
 151
 152         sprintf(buf, "%lu\n", morse_data->delay);
 153
 154         return strlen(buf) + 1;
 155 }
 156
 157 static ssize_t _morse_delay_store(struct led_classdev *led_cdev,
 158                 const char *buf, size_t size)
 159 {
 160         struct morse_trig_data *morse_data = led_cdev->trigger_data;
 161         char *after;
 162         unsigned long state = simple_strtoul(buf, &after, 10);
 163         size_t count = after - buf;
 164         int ret = -EINVAL;
 165
 166         if (*after && isspace(*after))
 167                 count++;
 168
 169         if (count == size) {
 170                 morse_data->delay = state;
 171                 mod_timer(&morse_data->timer, jiffies + 1);
 172                 ret = count;
 173         }
 174
 175         return ret;
 176 }
 177
 178 static ssize_t _morse_msg_show(struct led_classdev *led_cdev, char *buf)
 179 {
 180         struct morse_trig_data *morse_data = led_cdev->trigger_data;
 181
 182         if (!morse_data->msg)
 183                 sprintf(buf, "<none>\n");
 184         else
 185                 sprintf(buf, "%s\n", morse_data->msg);
 186
 187         return strlen(buf) + 1;
 188 }
 189
 190 static ssize_t _morse_msg_store(struct led_classdev *led_cdev,
 191                 const char *buf, size_t size)
 192 {
 193         struct morse_trig_data *morse_data = led_cdev->trigger_data;
 194         char *m;
 195
 196         m = kmalloc(size, GFP_KERNEL);
 197         if (!m)
 198                 return -ENOMEM;
 199
 200         memcpy(m,buf,size);
 201         m[size]='\0';
 202
 203         if (morse_data->msg)
 204                 kfree(morse_data->msg);
 205
 206         morse_data->msg = m;
 207         morse_data->msgpos = NULL;
 208         morse_data->state = MORSE_STATE_BLINK_STOP;
 209
 210         mod_timer(&morse_data->timer, jiffies + 1);
 211
 212         return size;
 213 }
 214
 215 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,23)
 216 static ssize_t morse_delay_show(struct device *dev,
 217                 struct device_attribute *attr, char *buf)
 218 {
 219         struct led_classdev *led_cdev = dev_get_drvdata(dev);
 220
 221         return _morse_delay_show(led_cdev, buf);
 222 }
 223
 224 static ssize_t morse_delay_store(struct device *dev,
 225                 struct device_attribute *attr, const char *buf, size_t size)
 226 {
 227         struct led_classdev *led_cdev = dev_get_drvdata(dev);
 228
 229         return _morse_delay_store(led_cdev, buf, size);
 230 }
 231
 232 static ssize_t morse_msg_show(struct device *dev,
 233                 struct device_attribute *attr, char *buf)
 234 {
 235         struct led_classdev *led_cdev = dev_get_drvdata(dev);
 236
 237         return _morse_msg_show(led_cdev, buf);
 238 }
 239
 240 static ssize_t morse_msg_store(struct device *dev,
 241                 struct device_attribute *attr, const char *buf, size_t size)
 242 {
 243         struct led_classdev *led_cdev = dev_get_drvdata(dev);
 244
 245         return _morse_msg_store(led_cdev, buf, size);
 246 }
 247
 248 static DEVICE_ATTR(delay, 0644, morse_delay_show, morse_delay_store);
 249 static DEVICE_ATTR(message, 0644, morse_msg_show, morse_msg_store);
 250
 251 #define led_device_create_file(leddev, attr) \
 252         device_create_file(leddev->dev, &dev_attr_ ## attr)
 253 #define led_device_remove_file(leddev, attr) \
 254         device_remove_file(leddev->dev, &dev_attr_ ## attr)
 255
 256 #else
 257 static ssize_t morse_delay_show(struct class_device *dev, char *buf)
 258 {
 259         struct led_classdev *led_cdev = class_get_devdata(dev);
 260
 261         return _morse_delay_show(led_cdev, buf);
 262 }
 263
 264 static ssize_t morse_delay_store(struct class_device *dev, const char *buf,
 265                 size_t size)
 266 {
 267         struct led_classdev *led_cdev = class_get_devdata(dev);
 268
 269         return _morse_delay_store(led_cdev, buf, size);
 270 }
 271
 272 static ssize_t morse_msg_show(struct class_device *dev, char *buf)
 273 {
 274         struct led_classdev *led_cdev = class_get_devdata(dev);
 275
 276         return _morse_msg_show(led_cdev, buf);
 277 }
 278
 279 static ssize_t morse_msg_store(struct class_device *dev, const char *buf,
 280                                 size_t size)
 281 {
 282         struct led_classdev *led_cdev = class_get_devdata(dev);
 283
 284         return _morse_msg_store(led_cdev, buf, size);
 285 }
 286
 287 static CLASS_DEVICE_ATTR(delay, 0644, morse_delay_show, morse_delay_store);
 288 static CLASS_DEVICE_ATTR(message, 0644, morse_msg_show, morse_msg_store);
 289
 290 #define led_device_create_file(leddev, attr) \
 291         class_device_create_file(leddev->class_dev, &class_device_attr_ ## attr)
 292 #define led_device_remove_file(leddev, attr) \
 293         class_device_remove_file(leddev->class_dev, &class_device_attr_ ## attr)
 294
 295 #endif
 296
 297 static void morse_trig_activate(struct led_classdev *led_cdev)
 298 {
 299         struct morse_trig_data *morse_data;
 300         int rc;
 301
 302         morse_data = kzalloc(sizeof(*morse_data), GFP_KERNEL);
 303         if (!morse_data)
 304                 return;
 305
 306         morse_data->delay = MORSE_DELAY_BASE;
 307         init_timer(&morse_data->timer);
 308         morse_data->timer.function = morse_timer_function;
 309         morse_data->timer.data = (unsigned long)led_cdev;
 310
 311         rc = led_device_create_file(led_cdev, delay);
 312         if (rc) goto err;
 313
 314         rc = led_device_create_file(led_cdev, message);
 315         if (rc) goto err_delay;
 316
 317         led_cdev->trigger_data = morse_data;
 318
 319         return;
 320
 321 err_delay:
 322         led_device_remove_file(led_cdev, delay);
 323 err:
 324         kfree(morse_data);
 325 }
 326
 327 static void morse_trig_deactivate(struct led_classdev *led_cdev)
 328 {
 329         struct morse_trig_data *morse_data = led_cdev->trigger_data;
 330
 331         if (!morse_data)
 332                 return;
 333
 334         led_device_remove_file(led_cdev, message);
 335         led_device_remove_file(led_cdev, delay);
 336
 337         del_timer_sync(&morse_data->timer);
 338         if (morse_data->msg)
 339                 kfree(morse_data->msg);
 340
 341         kfree(morse_data);
 342 }
 343
 344 static struct led_trigger morse_led_trigger = {
 345         .name           = "morse",
 346         .activate       = morse_trig_activate,
 347         .deactivate     = morse_trig_deactivate,
 348 };
 349
 350 static int __init morse_trig_init(void)
 351 {
 352         return led_trigger_register(&morse_led_trigger);
 353 }
 354
 355 static void __exit morse_trig_exit(void)
 356 {
 357         led_trigger_unregister(&morse_led_trigger);
 358 }
 359
 360 module_init(morse_trig_init);
 361 module_exit(morse_trig_exit);
 362
 363 MODULE_AUTHOR("Gabor Juhos <juhosg at openwrt.org>");
 364 MODULE_DESCRIPTION("Morse LED trigger");
 365 MODULE_LICENSE("GPL");