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 const char *display_textmodes[] = {"raw", "hex", "ascii"};
  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                 return;
 133
 134         /* The device is right to left, where as you write left to right */
 135         for (i = 0; i < mydev->textlength; i++)
 136                 buffer[i] = mydev->text[mydev->textlength-1-i];
 137
 138         rc = usb_control_msg(mydev->udev,
 139                         usb_sndctrlpipe(mydev->udev, 0),
 140                         0x12,
 141                         0x48,
 142                         (85 * 0x100) + 10, /* (write text) */
 143                         (0 * 0x100) + mydev->textmode, /* mode  */
 144                         buffer,
 145                         mydev->textlength,
 146                         2000);
 147
 148         if (rc < 0)
 149                 dev_dbg(&mydev->udev->dev, "write retval = %d\n", rc);
 150
 151         kfree(buffer);
 152
 153         /* The device is right to left, where as you write left to right */
 154         for (i = 0; i < sizeof(mydev->decimals); i++)
 155                 decimals |= mydev->decimals[i] << i;
 156
 157         rc = usb_control_msg(mydev->udev,
 158                         usb_sndctrlpipe(mydev->udev, 0),
 159                         0x12,
 160                         0x48,
 161                         (86 * 0x100) + 10, /* (set decimal) */
 162                         (0 * 0x100) + decimals, /* decimals */
 163                         NULL,
 164                         0,
 165                         2000);
 166
 167         if (rc < 0)
 168                 dev_dbg(&mydev->udev->dev, "decimal retval = %d\n", rc);
 169 }
 170
 171 #define MYDEV_ATTR_SIMPLE_UNSIGNED(name, update_fcn)            \
 172 static ssize_t show_attr_##name(struct device *dev,             \
 173         struct device_attribute *attr, char *buf)               \
 174 {                                                               \
 175         struct usb_interface *intf = to_usb_interface(dev);     \
 176         struct usb_sevsegdev *mydev = usb_get_intfdata(intf);   \
 177                                                                 \
 178         return sprintf(buf, "%u\n", mydev->name);               \
 179 }                                                               \
 180                                                                 \
 181 static ssize_t set_attr_##name(struct device *dev,              \
 182         struct device_attribute *attr, const char *buf, size_t count) \
 183 {                                                               \
 184         struct usb_interface *intf = to_usb_interface(dev);     \
 185         struct usb_sevsegdev *mydev = usb_get_intfdata(intf);   \
 186                                                                 \
 187         mydev->name = simple_strtoul(buf, NULL, 10);            \
 188         update_fcn(mydev);                                      \
 189                                                                 \
 190         return count;                                           \
 191 }                                                               \
 192 static DEVICE_ATTR(name, S_IRUGO | S_IWUSR, show_attr_##name, set_attr_##name);
 193
 194 static ssize_t show_attr_text(struct device *dev,
 195         struct device_attribute *attr, char *buf)
 196 {
 197         struct usb_interface *intf = to_usb_interface(dev);
 198         struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
 199
 200         return snprintf(buf, mydev->textlength, "%s\n", mydev->text);
 201 }
 202
 203 static ssize_t set_attr_text(struct device *dev,
 204         struct device_attribute *attr, const char *buf, size_t count)
 205 {
 206         struct usb_interface *intf = to_usb_interface(dev);
 207         struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
 208         size_t end = my_memlen(buf, count);
 209
 210         if (end > sizeof(mydev->text))
 211                 return -EINVAL;
 212
 213         memset(mydev->text, 0, sizeof(mydev->text));
 214         mydev->textlength = end;
 215
 216         if (end > 0)
 217                 memcpy(mydev->text, buf, end);
 218
 219         update_display_visual(mydev, GFP_KERNEL);
 220         return count;
 221 }
 222
 223 static DEVICE_ATTR(text, S_IRUGO | S_IWUSR, show_attr_text, set_attr_text);
 224
 225 static ssize_t show_attr_decimals(struct device *dev,
 226         struct device_attribute *attr, char *buf)
 227 {
 228         struct usb_interface *intf = to_usb_interface(dev);
 229         struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
 230         int i;
 231         int pos;
 232
 233         for (i = 0; i < sizeof(mydev->decimals); i++) {
 234                 pos = sizeof(mydev->decimals) - 1 - i;
 235                 if (mydev->decimals[i] == 0)
 236                         buf[pos] = '0';
 237                 else if (mydev->decimals[i] == 1)
 238                         buf[pos] = '1';
 239                 else
 240                         buf[pos] = 'x';
 241         }
 242
 243         buf[sizeof(mydev->decimals)] = '\n';
 244         return sizeof(mydev->decimals) + 1;
 245 }
 246
 247 static ssize_t set_attr_decimals(struct device *dev,
 248         struct device_attribute *attr, const char *buf, size_t count)
 249 {
 250         struct usb_interface *intf = to_usb_interface(dev);
 251         struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
 252         size_t end = my_memlen(buf, count);
 253         int i;
 254
 255         if (end > sizeof(mydev->decimals))
 256                 return -EINVAL;
 257
 258         for (i = 0; i < end; i++)
 259                 if (buf[i] != '0' && buf[i] != '1')
 260                         return -EINVAL;
 261
 262         memset(mydev->decimals, 0, sizeof(mydev->decimals));
 263         for (i = 0; i < end; i++)
 264                 if (buf[i] == '1')
 265                         mydev->decimals[end-1-i] = 1;
 266
 267         update_display_visual(mydev, GFP_KERNEL);
 268
 269         return count;
 270 }
 271
 272 static DEVICE_ATTR(decimals, S_IRUGO | S_IWUSR, show_attr_decimals, set_attr_decimals);
 273
 274 static ssize_t show_attr_textmode(struct device *dev,
 275         struct device_attribute *attr, char *buf)
 276 {
 277         struct usb_interface *intf = to_usb_interface(dev);
 278         struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
 279         int i;
 280
 281         buf[0] = 0;
 282
 283         for (i = 0; i < ARRAY_SIZE(display_textmodes); i++) {
 284                 if (mydev->textmode == i) {
 285                         strcat(buf, " [");
 286                         strcat(buf, display_textmodes[i]);
 287                         strcat(buf, "] ");
 288                 } else {
 289                         strcat(buf, " ");
 290                         strcat(buf, display_textmodes[i]);
 291                         strcat(buf, " ");
 292                 }
 293         }
 294         strcat(buf, "\n");
 295
 296
 297         return strlen(buf);
 298 }
 299
 300 static ssize_t set_attr_textmode(struct device *dev,
 301         struct device_attribute *attr, const char *buf, size_t count)
 302 {
 303         struct usb_interface *intf = to_usb_interface(dev);
 304         struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
 305         int i;
 306
 307         i = sysfs_match_string(display_textmodes, buf);
 308         if (i < 0)
 309                 return i;
 310
 311         mydev->textmode = i;
 312         update_display_visual(mydev, GFP_KERNEL);
 313         return count;
 314 }
 315
 316 static DEVICE_ATTR(textmode, S_IRUGO | S_IWUSR, 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)
 346                 goto error_mem;
 347
 348         mydev->udev = usb_get_dev(udev);
 349         mydev->intf = interface;
 350         usb_set_intfdata(interface, mydev);
 351
 352         /* PM */
 353         mydev->shadow_power = 1; /* currently active */
 354         mydev->has_interface_pm = 0; /* have not issued autopm_get */
 355
 356         /*set defaults */
 357         mydev->textmode = 0x02; /* ascii mode */
 358         mydev->mode_msb = 0x06; /* 6 characters */
 359         mydev->mode_lsb = 0x3f; /* scanmode for 6 chars */
 360
 361         rc = sysfs_create_group(&interface->dev.kobj, &dev_attr_grp);
 362         if (rc)
 363                 goto error;
 364
 365         dev_info(&interface->dev, "USB 7 Segment device now attached\n");
 366         return 0;
 367
 368 error:
 369         usb_set_intfdata(interface, NULL);
 370         usb_put_dev(mydev->udev);
 371         kfree(mydev);
 372 error_mem:
 373         return rc;
 374 }
 375
 376 static void sevseg_disconnect(struct usb_interface *interface)
 377 {
 378         struct usb_sevsegdev *mydev;
 379
 380         mydev = usb_get_intfdata(interface);
 381         sysfs_remove_group(&interface->dev.kobj, &dev_attr_grp);
 382         usb_set_intfdata(interface, NULL);
 383         usb_put_dev(mydev->udev);
 384         kfree(mydev);
 385         dev_info(&interface->dev, "USB 7 Segment now disconnected\n");
 386 }
 387
 388 static int sevseg_suspend(struct usb_interface *intf, pm_message_t message)
 389 {
 390         struct usb_sevsegdev *mydev;
 391
 392         mydev = usb_get_intfdata(intf);
 393         mydev->shadow_power = 0;
 394
 395         return 0;
 396 }
 397
 398 static int sevseg_resume(struct usb_interface *intf)
 399 {
 400         struct usb_sevsegdev *mydev;
 401
 402         mydev = usb_get_intfdata(intf);
 403         mydev->shadow_power = 1;
 404         update_display_mode(mydev);
 405         update_display_visual(mydev, GFP_NOIO);
 406
 407         return 0;
 408 }
 409
 410 static int sevseg_reset_resume(struct usb_interface *intf)
 411 {
 412         struct usb_sevsegdev *mydev;
 413
 414         mydev = usb_get_intfdata(intf);
 415         mydev->shadow_power = 1;
 416         update_display_mode(mydev);
 417         update_display_visual(mydev, GFP_NOIO);
 418
 419         return 0;
 420 }
 421
 422 static struct usb_driver sevseg_driver = {
 423         .name =         "usbsevseg",
 424         .probe =        sevseg_probe,
 425         .disconnect =   sevseg_disconnect,
 426         .suspend =      sevseg_suspend,
 427         .resume =       sevseg_resume,
 428         .reset_resume = sevseg_reset_resume,
 429         .id_table =     id_table,
 430         .supports_autosuspend = 1,
 431 };
 432
 433 module_usb_driver(sevseg_driver);
 434
 435 MODULE_AUTHOR(DRIVER_AUTHOR);
 436 MODULE_DESCRIPTION(DRIVER_DESC);
 437 MODULE_LICENSE("GPL");