drivers/usb/misc/usbsevseg.c

   1 /*
   2  * USB 7 Segment Driver
   3  *
   4  * Copyright (C) 2008 Harrison Metzger <harrisonmetz@gmail.com>
   5  * Based on usbled.c by Greg Kroah-Hartman (greg@kroah.com)
   6  *
   7  *      This program is free software; you can redistribute it and/or
   8  *      modify it under the terms of the GNU General Public License as
   9  *      published by the Free Software Foundation, version 2.
  10  *
  11  */
  12
  13 #include <linux/kernel.h>
  14 #include <linux/errno.h>
  15 #include <linux/init.h>
  16 #include <linux/slab.h>
  17 #include <linux/module.h>
  18 #include <linux/string.h>
  19 #include <linux/usb.h>
  20
  21
  22 #define DRIVER_AUTHOR "Harrison Metzger <harrisonmetz@gmail.com>"
  23 #define DRIVER_DESC "USB 7 Segment Driver"
  24
  25 #define VENDOR_ID       0x0fc5
  26 #define PRODUCT_ID      0x1227
  27 #define MAXLEN          6
  28
  29 /* table of devices that work with this driver */
  30 static const struct usb_device_id id_table[] = {
  31         { USB_DEVICE(VENDOR_ID, PRODUCT_ID) },
  32         { },
  33 };
  34 MODULE_DEVICE_TABLE(usb, id_table);
  35
  36 /* the different text display modes the device is capable of */
  37 static char *display_textmodes[] = {"raw", "hex", "ascii", NULL};
  38
  39 struct usb_sevsegdev {
  40         struct usb_device *udev;
  41         struct usb_interface *intf;
  42
  43         u8 powered;
  44         u8 mode_msb;
  45         u8 mode_lsb;
  46         u8 decimals[MAXLEN];
  47         u8 textmode;
  48         u8 text[MAXLEN];
  49         u16 textlength;
  50
  51         u8 shadow_power; /* for PM */
  52         u8 has_interface_pm;
  53 };
  54
  55 /* sysfs_streq can't replace this completely
  56  * If the device was in hex mode, and the user wanted a 0,
  57  * if str commands are used, we would assume the end of string
  58  * so mem commands are used.
  59  */
  60 inline size_t my_memlen(const char *buf, size_t count)
  61 {
  62         if (count > 0 && buf[count-1] == '\n')
  63                 return count - 1;
  64         else
  65                 return count;
  66 }
  67
  68 static void update_display_powered(struct usb_sevsegdev *mydev)
  69 {
  70         int rc;
  71
  72         if (mydev->powered && !mydev->has_interface_pm) {
  73                 rc = usb_autopm_get_interface(mydev->intf);
  74                 if (rc < 0)
  75                         return;
  76                 mydev->has_interface_pm = 1;
  77         }
  78
  79         if (mydev->shadow_power != 1)
  80                 return;
  81
  82         rc = usb_control_msg(mydev->udev,
  83                         usb_sndctrlpipe(mydev->udev, 0),
  84                         0x12,
  85                         0x48,
  86                         (80 * 0x100) + 10, /*  (power mode) */
  87                         (0x00 * 0x100) + (mydev->powered ? 1 : 0),
  88                         NULL,
  89                         0,
  90                         2000);
  91         if (rc < 0)
  92                 dev_dbg(&mydev->udev->dev, "power retval = %d\n", rc);
  93
  94         if (!mydev->powered && mydev->has_interface_pm) {
  95                 usb_autopm_put_interface(mydev->intf);
  96                 mydev->has_interface_pm = 0;
  97         }
  98 }
  99
 100 static void update_display_mode(struct usb_sevsegdev *mydev)
 101 {
 102         int rc;
 103
 104         if(mydev->shadow_power != 1)
 105                 return;
 106
 107         rc = usb_control_msg(mydev->udev,
 108                         usb_sndctrlpipe(mydev->udev, 0),
 109                         0x12,
 110                         0x48,
 111                         (82 * 0x100) + 10, /* (set mode) */
 112                         (mydev->mode_msb * 0x100) + mydev->mode_lsb,
 113                         NULL,
 114                         0,
 115                         2000);
 116
 117         if (rc < 0)
 118                 dev_dbg(&mydev->udev->dev, "mode retval = %d\n", rc);
 119 }
 120
 121 static void update_display_visual(struct usb_sevsegdev *mydev, gfp_t mf)
 122 {
 123         int rc;
 124         int i;
 125         unsigned char *buffer;
 126         u8 decimals = 0;
 127
 128         if(mydev->shadow_power != 1)
 129                 return;
 130
 131         buffer = kzalloc(MAXLEN, mf);
 132         if (!buffer) {
 133                 dev_err(&mydev->udev->dev, "out of memory\n");
 134                 return;
 135         }
 136
 137         /* The device is right to left, where as you write left to right */
 138         for (i = 0; i < mydev->textlength; i++)
 139                 buffer[i] = mydev->text[mydev->textlength-1-i];
 140
 141         rc = usb_control_msg(mydev->udev,
 142                         usb_sndctrlpipe(mydev->udev, 0),
 143                         0x12,
 144                         0x48,
 145                         (85 * 0x100) + 10, /* (write text) */
 146                         (0 * 0x100) + mydev->textmode, /* mode  */
 147                         buffer,
 148                         mydev->textlength,
 149                         2000);
 150
 151         if (rc < 0)
 152                 dev_dbg(&mydev->udev->dev, "write retval = %d\n", rc);
 153
 154         kfree(buffer);
 155
 156         /* The device is right to left, where as you write left to right */
 157         for (i = 0; i < sizeof(mydev->decimals); i++)
 158                 decimals |= mydev->decimals[i] << i;
 159
 160         rc = usb_control_msg(mydev->udev,
 161                         usb_sndctrlpipe(mydev->udev, 0),
 162                         0x12,
 163                         0x48,
 164                         (86 * 0x100) + 10, /* (set decimal) */
 165                         (0 * 0x100) + decimals, /* decimals */
 166                         NULL,
 167                         0,
 168                         2000);
 169
 170         if (rc < 0)
 171                 dev_dbg(&mydev->udev->dev, "decimal retval = %d\n", rc);
 172 }
 173
 174 #define MYDEV_ATTR_SIMPLE_UNSIGNED(name, update_fcn)            \
 175 static ssize_t show_attr_##name(struct device *dev,             \
 176         struct device_attribute *attr, char *buf)               \
 177 {                                                               \
 178         struct usb_interface *intf = to_usb_interface(dev);     \
 179         struct usb_sevsegdev *mydev = usb_get_intfdata(intf);   \
 180                                                                 \
 181         return sprintf(buf, "%u\n", mydev->name);               \
 182 }                                                               \
 183                                                                 \
 184 static ssize_t set_attr_##name(struct device *dev,              \
 185         struct device_attribute *attr, const char *buf, size_t count) \
 186 {                                                               \
 187         struct usb_interface *intf = to_usb_interface(dev);     \
 188         struct usb_sevsegdev *mydev = usb_get_intfdata(intf);   \
 189                                                                 \
 190         mydev->name = simple_strtoul(buf, NULL, 10);            \
 191         update_fcn(mydev);                                      \
 192                                                                 \
 193         return count;                                           \
 194 }                                                               \
 195 static DEVICE_ATTR(name, S_IWUGO | S_IRUGO, show_attr_##name, set_attr_##name);
 196
 197 static ssize_t show_attr_text(struct device *dev,
 198         struct device_attribute *attr, char *buf)
 199 {
 200         struct usb_interface *intf = to_usb_interface(dev);
 201         struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
 202
 203         return snprintf(buf, mydev->textlength, "%s\n", mydev->text);
 204 }
 205
 206 static ssize_t set_attr_text(struct device *dev,
 207         struct device_attribute *attr, const char *buf, size_t count)
 208 {
 209         struct usb_interface *intf = to_usb_interface(dev);
 210         struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
 211         size_t end = my_memlen(buf, count);
 212
 213         if (end > sizeof(mydev->text))
 214                 return -EINVAL;
 215
 216         memset(mydev->text, 0, sizeof(mydev->text));
 217         mydev->textlength = end;
 218
 219         if (end > 0)
 220                 memcpy(mydev->text, buf, end);
 221
 222         update_display_visual(mydev, GFP_KERNEL);
 223         return count;
 224 }
 225
 226 static DEVICE_ATTR(text, S_IWUGO | S_IRUGO, show_attr_text, set_attr_text);
 227
 228 static ssize_t show_attr_decimals(struct device *dev,
 229         struct device_attribute *attr, char *buf)
 230 {
 231         struct usb_interface *intf = to_usb_interface(dev);
 232         struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
 233         int i;
 234         int pos;
 235
 236         for (i = 0; i < sizeof(mydev->decimals); i++) {
 237                 pos = sizeof(mydev->decimals) - 1 - i;
 238                 if (mydev->decimals[i] == 0)
 239                         buf[pos] = '0';
 240                 else if (mydev->decimals[i] == 1)
 241                         buf[pos] = '1';
 242                 else
 243                         buf[pos] = 'x';
 244         }
 245
 246         buf[sizeof(mydev->decimals)] = '\n';
 247         return sizeof(mydev->decimals) + 1;
 248 }
 249
 250 static ssize_t set_attr_decimals(struct device *dev,
 251         struct device_attribute *attr, const char *buf, size_t count)
 252 {
 253         struct usb_interface *intf = to_usb_interface(dev);
 254         struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
 255         size_t end = my_memlen(buf, count);
 256         int i;
 257
 258         if (end > sizeof(mydev->decimals))
 259                 return -EINVAL;
 260
 261         for (i = 0; i < end; i++)
 262                 if (buf[i] != '0' && buf[i] != '1')
 263                         return -EINVAL;
 264
 265         memset(mydev->decimals, 0, sizeof(mydev->decimals));
 266         for (i = 0; i < end; i++)
 267                 if (buf[i] == '1')
 268                         mydev->decimals[end-1-i] = 1;
 269
 270         update_display_visual(mydev, GFP_KERNEL);
 271
 272         return count;
 273 }
 274
 275 static DEVICE_ATTR(decimals, S_IWUGO | S_IRUGO,
 276         show_attr_decimals, set_attr_decimals);
 277
 278 static ssize_t show_attr_textmode(struct device *dev,
 279         struct device_attribute *attr, char *buf)
 280 {
 281         struct usb_interface *intf = to_usb_interface(dev);
 282         struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
 283         int i;
 284
 285         buf[0] = 0;
 286
 287         for (i = 0; display_textmodes[i]; i++) {
 288                 if (mydev->textmode == i) {
 289                         strcat(buf, " [");
 290                         strcat(buf, display_textmodes[i]);
 291                         strcat(buf, "] ");
 292                 } else {
 293                         strcat(buf, " ");
 294                         strcat(buf, display_textmodes[i]);
 295                         strcat(buf, " ");
 296                 }
 297         }
 298         strcat(buf, "\n");
 299
 300
 301         return strlen(buf);
 302 }
 303
 304 static ssize_t set_attr_textmode(struct device *dev,
 305         struct device_attribute *attr, const char *buf, size_t count)
 306 {
 307         struct usb_interface *intf = to_usb_interface(dev);
 308         struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
 309         int i;
 310
 311         for (i = 0; display_textmodes[i]; i++) {
 312                 if (sysfs_streq(display_textmodes[i], buf)) {
 313                         mydev->textmode = i;
 314                         update_display_visual(mydev, GFP_KERNEL);
 315                         return count;
 316                 }
 317         }
 318
 319         return -EINVAL;
 320 }
 321
 322 static DEVICE_ATTR(textmode, S_IWUGO | S_IRUGO,
 323         show_attr_textmode, set_attr_textmode);
 324
 325
 326 MYDEV_ATTR_SIMPLE_UNSIGNED(powered, update_display_powered);
 327 MYDEV_ATTR_SIMPLE_UNSIGNED(mode_msb, update_display_mode);
 328 MYDEV_ATTR_SIMPLE_UNSIGNED(mode_lsb, update_display_mode);
 329
 330 static struct attribute *dev_attrs[] = {
 331         &dev_attr_powered.attr,
 332         &dev_attr_text.attr,
 333         &dev_attr_textmode.attr,
 334         &dev_attr_decimals.attr,
 335         &dev_attr_mode_msb.attr,
 336         &dev_attr_mode_lsb.attr,
 337         NULL
 338 };
 339
 340 static struct attribute_group dev_attr_grp = {
 341         .attrs = dev_attrs,
 342 };
 343
 344 static int sevseg_probe(struct usb_interface *interface,
 345         const struct usb_device_id *id)
 346 {
 347         struct usb_device *udev = interface_to_usbdev(interface);
 348         struct usb_sevsegdev *mydev = NULL;
 349         int rc = -ENOMEM;
 350
 351         mydev = kzalloc(sizeof(struct usb_sevsegdev), GFP_KERNEL);
 352         if (mydev == NULL) {
 353                 dev_err(&interface->dev, "Out of memory\n");
 354                 goto error_mem;
 355         }
 356
 357         mydev->udev = usb_get_dev(udev);
 358         mydev->intf = interface;
 359         usb_set_intfdata(interface, mydev);
 360
 361         /* PM */
 362         mydev->shadow_power = 1; /* currently active */
 363         mydev->has_interface_pm = 0; /* have not issued autopm_get */
 364
 365         /*set defaults */
 366         mydev->textmode = 0x02; /* ascii mode */
 367         mydev->mode_msb = 0x06; /* 6 characters */
 368         mydev->mode_lsb = 0x3f; /* scanmode for 6 chars */
 369
 370         rc = sysfs_create_group(&interface->dev.kobj, &dev_attr_grp);
 371         if (rc)
 372                 goto error;
 373
 374         dev_info(&interface->dev, "USB 7 Segment device now attached\n");
 375         return 0;
 376
 377 error:
 378         usb_set_intfdata(interface, NULL);
 379         usb_put_dev(mydev->udev);
 380         kfree(mydev);
 381 error_mem:
 382         return rc;
 383 }
 384
 385 static void sevseg_disconnect(struct usb_interface *interface)
 386 {
 387         struct usb_sevsegdev *mydev;
 388
 389         mydev = usb_get_intfdata(interface);
 390         sysfs_remove_group(&interface->dev.kobj, &dev_attr_grp);
 391         usb_set_intfdata(interface, NULL);
 392         usb_put_dev(mydev->udev);
 393         kfree(mydev);
 394         dev_info(&interface->dev, "USB 7 Segment now disconnected\n");
 395 }
 396
 397 static int sevseg_suspend(struct usb_interface *intf, pm_message_t message)
 398 {
 399         struct usb_sevsegdev *mydev;
 400
 401         mydev = usb_get_intfdata(intf);
 402         mydev->shadow_power = 0;
 403
 404         return 0;
 405 }
 406
 407 static int sevseg_resume(struct usb_interface *intf)
 408 {
 409         struct usb_sevsegdev *mydev;
 410
 411         mydev = usb_get_intfdata(intf);
 412         mydev->shadow_power = 1;
 413         update_display_mode(mydev);
 414         update_display_visual(mydev, GFP_NOIO);
 415
 416         return 0;
 417 }
 418
 419 static int sevseg_reset_resume(struct usb_interface *intf)
 420 {
 421         struct usb_sevsegdev *mydev;
 422
 423         mydev = usb_get_intfdata(intf);
 424         mydev->shadow_power = 1;
 425         update_display_mode(mydev);
 426         update_display_visual(mydev, GFP_NOIO);
 427
 428         return 0;
 429 }
 430
 431 static struct usb_driver sevseg_driver = {
 432         .name =         "usbsevseg",
 433         .probe =        sevseg_probe,
 434         .disconnect =   sevseg_disconnect,
 435         .suspend =      sevseg_suspend,
 436         .resume =       sevseg_resume,
 437         .reset_resume = sevseg_reset_resume,
 438         .id_table =     id_table,
 439         .supports_autosuspend = 1,
 440 };
 441
 442 static int __init usb_sevseg_init(void)
 443 {
 444         int rc = 0;
 445
 446         rc = usb_register(&sevseg_driver);
 447         if (rc)
 448                 err("usb_register failed. Error number %d", rc);
 449         return rc;
 450 }
 451
 452 static void __exit usb_sevseg_exit(void)
 453 {
 454         usb_deregister(&sevseg_driver);
 455 }
 456
 457 module_init(usb_sevseg_init);
 458 module_exit(usb_sevseg_exit);
 459
 460 MODULE_AUTHOR(DRIVER_AUTHOR);
 461 MODULE_DESCRIPTION(DRIVER_DESC);
 462 MODULE_LICENSE("GPL");