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