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