drivers/usb/misc/usbsevseg.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * USB 7 Segment Driver
   4  *
   5  * Copyright (C) 2008 Harrison Metzger <harrisonmetz@gmail.com>
   6  * Based on usbled.c by Greg Kroah-Hartman (greg@kroah.com)
   7  */
   8
   9 #include <linux/kernel.h>
  10 #include <linux/errno.h>
  11 #include <linux/slab.h>
  12 #include <linux/module.h>
  13 #include <linux/string.h>
  14 #include <linux/usb.h>
  15
  16
  17 #define DRIVER_AUTHOR "Harrison Metzger <harrisonmetz@gmail.com>"
  18 #define DRIVER_DESC "USB 7 Segment Driver"
  19
  20 #define VENDOR_ID       0x0fc5
  21 #define PRODUCT_ID      0x1227
  22 #define MAXLEN          8
  23
  24 /* table of devices that work with this driver */
  25 static const struct usb_device_id id_table[] = {
  26         { USB_DEVICE(VENDOR_ID, PRODUCT_ID) },
  27         { },
  28 };
  29 MODULE_DEVICE_TABLE(usb, id_table);
  30
  31 /* the different text display modes the device is capable of */
  32 static const char *display_textmodes[] = {"raw", "hex", "ascii"};
  33
  34 struct usb_sevsegdev {
  35         struct usb_device *udev;
  36         struct usb_interface *intf;
  37
  38         u8 powered;
  39         u8 mode_msb;
  40         u8 mode_lsb;
  41         u8 decimals[MAXLEN];
  42         u8 textmode;
  43         u8 text[MAXLEN];
  44         u16 textlength;
  45
  46         u8 shadow_power; /* for PM */
  47         u8 has_interface_pm;
  48 };
  49
  50 /* sysfs_streq can't replace this completely
  51  * If the device was in hex mode, and the user wanted a 0,
  52  * if str commands are used, we would assume the end of string
  53  * so mem commands are used.
  54  */
  55 static inline size_t my_memlen(const char *buf, size_t count)
  56 {
  57         if (count > 0 && buf[count-1] == '\n')
  58                 return count - 1;
  59         else
  60                 return count;
  61 }
  62
  63 static void update_display_powered(struct usb_sevsegdev *mydev)
  64 {
  65         int rc;
  66
  67         if (mydev->powered && !mydev->has_interface_pm) {
  68                 rc = usb_autopm_get_interface(mydev->intf);
  69                 if (rc < 0)
  70                         return;
  71                 mydev->has_interface_pm = 1;
  72         }
  73
  74         if (mydev->shadow_power != 1)
  75                 return;
  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->powered && mydev->has_interface_pm) {
  90                 usb_autopm_put_interface(mydev->intf);
  91                 mydev->has_interface_pm = 0;
  92         }
  93 }
  94
  95 static void update_display_mode(struct usb_sevsegdev *mydev)
  96 {
  97         int rc;
  98
  99         if(mydev->shadow_power != 1)
 100                 return;
 101
 102         rc = usb_control_msg(mydev->udev,
 103                         usb_sndctrlpipe(mydev->udev, 0),
 104                         0x12,
 105                         0x48,
 106                         (82 * 0x100) + 10, /* (set mode) */
 107                         (mydev->mode_msb * 0x100) + mydev->mode_lsb,
 108                         NULL,
 109                         0,
 110                         2000);
 111
 112         if (rc < 0)
 113                 dev_dbg(&mydev->udev->dev, "mode retval = %d\n", rc);
 114 }
 115
 116 static void update_display_visual(struct usb_sevsegdev *mydev, gfp_t mf)
 117 {
 118         int rc;
 119         int i;
 120         unsigned char *buffer;
 121         u8 decimals = 0;
 122
 123         if(mydev->shadow_power != 1)
 124                 return;
 125
 126         buffer = kzalloc(MAXLEN, mf);
 127         if (!buffer)
 128                 return;
 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 name##_show(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 name##_store(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_RW(name);
 189
 190 static ssize_t text_show(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 text_store(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_RW(text);
 220
 221 static ssize_t decimals_show(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 decimals_store(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_RW(decimals);
 269
 270 static ssize_t textmode_show(struct device *dev,
 271         struct device_attribute *attr, char *buf)
 272 {
 273         struct usb_interface *intf = to_usb_interface(dev);
 274         struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
 275         int i;
 276
 277         buf[0] = 0;
 278
 279         for (i = 0; i < ARRAY_SIZE(display_textmodes); i++) {
 280                 if (mydev->textmode == i) {
 281                         strcat(buf, " [");
 282                         strcat(buf, display_textmodes[i]);
 283                         strcat(buf, "] ");
 284                 } else {
 285                         strcat(buf, " ");
 286                         strcat(buf, display_textmodes[i]);
 287                         strcat(buf, " ");
 288                 }
 289         }
 290         strcat(buf, "\n");
 291
 292
 293         return strlen(buf);
 294 }
 295
 296 static ssize_t textmode_store(struct device *dev,
 297         struct device_attribute *attr, const char *buf, size_t count)
 298 {
 299         struct usb_interface *intf = to_usb_interface(dev);
 300         struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
 301         int i;
 302
 303         i = sysfs_match_string(display_textmodes, buf);
 304         if (i < 0)
 305                 return i;
 306
 307         mydev->textmode = i;
 308         update_display_visual(mydev, GFP_KERNEL);
 309         return count;
 310 }
 311
 312 static DEVICE_ATTR_RW(textmode);
 313
 314
 315 MYDEV_ATTR_SIMPLE_UNSIGNED(powered, update_display_powered);
 316 MYDEV_ATTR_SIMPLE_UNSIGNED(mode_msb, update_display_mode);
 317 MYDEV_ATTR_SIMPLE_UNSIGNED(mode_lsb, update_display_mode);
 318
 319 static struct attribute *dev_attrs[] = {
 320         &dev_attr_powered.attr,
 321         &dev_attr_text.attr,
 322         &dev_attr_textmode.attr,
 323         &dev_attr_decimals.attr,
 324         &dev_attr_mode_msb.attr,
 325         &dev_attr_mode_lsb.attr,
 326         NULL
 327 };
 328
 329 static const struct attribute_group dev_attr_grp = {
 330         .attrs = dev_attrs,
 331 };
 332
 333 static int sevseg_probe(struct usb_interface *interface,
 334         const struct usb_device_id *id)
 335 {
 336         struct usb_device *udev = interface_to_usbdev(interface);
 337         struct usb_sevsegdev *mydev = NULL;
 338         int rc = -ENOMEM;
 339
 340         mydev = kzalloc(sizeof(struct usb_sevsegdev), GFP_KERNEL);
 341         if (!mydev)
 342                 goto error_mem;
 343
 344         mydev->udev = usb_get_dev(udev);
 345         mydev->intf = interface;
 346         usb_set_intfdata(interface, mydev);
 347
 348         /* PM */
 349         mydev->shadow_power = 1; /* currently active */
 350         mydev->has_interface_pm = 0; /* have not issued autopm_get */
 351
 352         /*set defaults */
 353         mydev->textmode = 0x02; /* ascii mode */
 354         mydev->mode_msb = 0x06; /* 6 characters */
 355         mydev->mode_lsb = 0x3f; /* scanmode for 6 chars */
 356
 357         rc = sysfs_create_group(&interface->dev.kobj, &dev_attr_grp);
 358         if (rc)
 359                 goto error;
 360
 361         dev_info(&interface->dev, "USB 7 Segment device now attached\n");
 362         return 0;
 363
 364 error:
 365         usb_set_intfdata(interface, NULL);
 366         usb_put_dev(mydev->udev);
 367         kfree(mydev);
 368 error_mem:
 369         return rc;
 370 }
 371
 372 static void sevseg_disconnect(struct usb_interface *interface)
 373 {
 374         struct usb_sevsegdev *mydev;
 375
 376         mydev = usb_get_intfdata(interface);
 377         sysfs_remove_group(&interface->dev.kobj, &dev_attr_grp);
 378         usb_set_intfdata(interface, NULL);
 379         usb_put_dev(mydev->udev);
 380         kfree(mydev);
 381         dev_info(&interface->dev, "USB 7 Segment now disconnected\n");
 382 }
 383
 384 static int sevseg_suspend(struct usb_interface *intf, pm_message_t message)
 385 {
 386         struct usb_sevsegdev *mydev;
 387
 388         mydev = usb_get_intfdata(intf);
 389         mydev->shadow_power = 0;
 390
 391         return 0;
 392 }
 393
 394 static int sevseg_resume(struct usb_interface *intf)
 395 {
 396         struct usb_sevsegdev *mydev;
 397
 398         mydev = usb_get_intfdata(intf);
 399         mydev->shadow_power = 1;
 400         update_display_mode(mydev);
 401         update_display_visual(mydev, GFP_NOIO);
 402
 403         return 0;
 404 }
 405
 406 static int sevseg_reset_resume(struct usb_interface *intf)
 407 {
 408         struct usb_sevsegdev *mydev;
 409
 410         mydev = usb_get_intfdata(intf);
 411         mydev->shadow_power = 1;
 412         update_display_mode(mydev);
 413         update_display_visual(mydev, GFP_NOIO);
 414
 415         return 0;
 416 }
 417
 418 static struct usb_driver sevseg_driver = {
 419         .name =         "usbsevseg",
 420         .probe =        sevseg_probe,
 421         .disconnect =   sevseg_disconnect,
 422         .suspend =      sevseg_suspend,
 423         .resume =       sevseg_resume,
 424         .reset_resume = sevseg_reset_resume,
 425         .id_table =     id_table,
 426         .supports_autosuspend = 1,
 427 };
 428
 429 module_usb_driver(sevseg_driver);
 430
 431 MODULE_AUTHOR(DRIVER_AUTHOR);
 432 MODULE_DESCRIPTION(DRIVER_DESC);
 433 MODULE_LICENSE("GPL");