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