drivers/usb/misc/usblcd.c

   1 /*****************************************************************************
   2  *                          USBLCD Kernel Driver                             *
   3  *        See http://www.usblcd.de for Hardware and Documentation.           *
   4  *                            Version 1.03                                   *
   5  *             (C) 2002 Adams IT Services <info@usblcd.de>                   *
   6  *                                                                           *
   7  *     This file is licensed under the GPL. See COPYING in the package.      *
   8  * Based on rio500.c by Cesar Miquel (miquel@df.uba.ar) which is based on    *
   9  * hp_scanner.c by David E. Nelson (dnelson@jump.net)                        *
  10  *                                                                           *
  11  * 23.7.02 RA changed minor device number to the official assigned one       *
  12  *****************************************************************************/
  13 #include <linux/module.h>
  14 #include <linux/kernel.h>
  15 #include <linux/init.h>
  16 #include <linux/slab.h>
  17 #include <linux/errno.h>
  18 #include <asm/uaccess.h>
  19 #include <linux/usb.h>
  20
  21 #define DRIVER_VERSION "USBLCD Driver Version 1.04"
  22
  23 #define USBLCD_MINOR            144
  24
  25 #define IOCTL_GET_HARD_VERSION  1
  26 #define IOCTL_GET_DRV_VERSION   2
  27
  28 /* stall/wait timeout for USBLCD */
  29 #define NAK_TIMEOUT     (10*HZ)
  30
  31 #define IBUF_SIZE       0x1000
  32 #define OBUF_SIZE       0x10000
  33
  34 struct lcd_usb_data {
  35         struct usb_device *lcd_dev;     /* init: probe_lcd */
  36         unsigned int ifnum;             /* Interface number of the USB device */
  37         int isopen;                     /* nz if open */
  38         int present;                    /* Device is present on the bus */
  39         char *obuf, *ibuf;              /* transfer buffers */
  40         char bulk_in_ep, bulk_out_ep;   /* Endpoint assignments */
  41         wait_queue_head_t wait_q;       /* for timeouts */
  42 };
  43
  44 static struct lcd_usb_data lcd_instance;
  45
  46 static int open_lcd(struct inode *inode, struct file *file)
  47 {
  48         struct lcd_usb_data *lcd = &lcd_instance;
  49
  50         if (lcd->isopen || !lcd->present) {
  51                 return -EBUSY;
  52         }
  53         lcd->isopen = 1;
  54
  55         init_waitqueue_head(&lcd->wait_q);
  56
  57         info("USBLCD opened.");
  58
  59         return 0;
  60 }
  61
  62 static int close_lcd(struct inode *inode, struct file *file)
  63 {
  64         struct lcd_usb_data *lcd = &lcd_instance;
  65
  66         lcd->isopen = 0;
  67
  68         info("USBLCD closed.");
  69         return 0;
  70 }
  71
  72 static int
  73 ioctl_lcd(struct inode *inode, struct file *file, unsigned int cmd,
  74           unsigned long arg)
  75 {
  76         struct lcd_usb_data *lcd = &lcd_instance;
  77         u16 bcdDevice;
  78         char buf[30];
  79
  80         /* Sanity check to make sure lcd is connected, powered, etc */
  81         if (lcd == NULL ||
  82             lcd->present == 0 ||
  83             lcd->lcd_dev == NULL)
  84                 return -1;
  85
  86         switch (cmd) {
  87         case IOCTL_GET_HARD_VERSION:
  88                 bcdDevice = le16_to_cpu((lcd->lcd_dev)->descriptor.bcdDevice);
  89                 sprintf(buf,"%1d%1d.%1d%1d",
  90                         (bcdDevice & 0xF000)>>12,
  91                         (bcdDevice & 0xF00)>>8,
  92                         (bcdDevice & 0xF0)>>4,
  93                         (bcdDevice & 0xF));
  94                 if (copy_to_user((void __user *)arg,buf,strlen(buf))!=0)
  95                         return -EFAULT;
  96                 break;
  97         case IOCTL_GET_DRV_VERSION:
  98                 sprintf(buf,DRIVER_VERSION);
  99                 if (copy_to_user((void __user *)arg,buf,strlen(buf))!=0)
 100                         return -EFAULT;
 101                 break;
 102         default:
 103                 return -ENOTTY;
 104                 break;
 105         }
 106
 107         return 0;
 108 }
 109
 110 static ssize_t
 111 write_lcd(struct file *file, const char __user *buffer,
 112           size_t count, loff_t * ppos)
 113 {
 114         struct lcd_usb_data *lcd = &lcd_instance;
 115
 116         unsigned long copy_size;
 117         unsigned long bytes_written = 0;
 118         unsigned int partial;
 119
 120         int result = 0;
 121         int maxretry;
 122
 123         /* Sanity check to make sure lcd is connected, powered, etc */
 124         if (lcd == NULL ||
 125             lcd->present == 0 ||
 126             lcd->lcd_dev == NULL)
 127                 return -1;
 128
 129         do {
 130                 unsigned long thistime;
 131                 char *obuf = lcd->obuf;
 132
 133                 thistime = copy_size =
 134                     (count >= OBUF_SIZE) ? OBUF_SIZE : count;
 135                 if (copy_from_user(lcd->obuf, buffer, copy_size))
 136                         return -EFAULT;
 137                 maxretry = 5;
 138                 while (thistime) {
 139                         if (!lcd->lcd_dev)
 140                                 return -ENODEV;
 141                         if (signal_pending(current)) {
 142                                 return bytes_written ? bytes_written : -EINTR;
 143                         }
 144
 145                         result = usb_bulk_msg(lcd->lcd_dev,
 146                                          usb_sndbulkpipe(lcd->lcd_dev, 1),
 147                                          obuf, thistime, &partial, 10 * HZ);
 148
 149                         dbg("write stats: result:%d thistime:%lu partial:%u",
 150                              result, thistime, partial);
 151
 152                         if (result == -ETIMEDOUT) {     /* NAK - so hold for a while */
 153                                 if (!maxretry--) {
 154                                         return -ETIME;
 155                                 }
 156                                 interruptible_sleep_on_timeout(&lcd-> wait_q, NAK_TIMEOUT);
 157                                 continue;
 158                         } else if (!result && partial) {
 159                                 obuf += partial;
 160                                 thistime -= partial;
 161                         } else
 162                                 break;
 163                 };
 164                 if (result) {
 165                         err("Write Whoops - %x", result);
 166                         return -EIO;
 167                 }
 168                 bytes_written += copy_size;
 169                 count -= copy_size;
 170                 buffer += copy_size;
 171         } while (count > 0);
 172
 173         return bytes_written ? bytes_written : -EIO;
 174 }
 175
 176 static ssize_t
 177 read_lcd(struct file *file, char __user *buffer, size_t count, loff_t * ppos)
 178 {
 179         struct lcd_usb_data *lcd = &lcd_instance;
 180         ssize_t read_count;
 181         unsigned int partial;
 182         int this_read;
 183         int result;
 184         int maxretry = 10;
 185         char *ibuf = lcd->ibuf;
 186
 187         /* Sanity check to make sure lcd is connected, powered, etc */
 188         if (lcd == NULL ||
 189             lcd->present == 0 ||
 190             lcd->lcd_dev == NULL)
 191                 return -1;
 192
 193         read_count = 0;
 194
 195         while (count > 0) {
 196                 if (signal_pending(current)) {
 197                         return read_count ? read_count : -EINTR;
 198                 }
 199                 if (!lcd->lcd_dev)
 200                         return -ENODEV;
 201                 this_read = (count >= IBUF_SIZE) ? IBUF_SIZE : count;
 202
 203                 result = usb_bulk_msg(lcd->lcd_dev,
 204                                       usb_rcvbulkpipe(lcd->lcd_dev, 0),
 205                                       ibuf, this_read, &partial,
 206                                       (int) (HZ * 8));
 207
 208                 dbg(KERN_DEBUG "read stats: result:%d this_read:%u partial:%u",
 209                        result, this_read, partial);
 210
 211                 if (partial) {
 212                         count = this_read = partial;
 213                 } else if (result == -ETIMEDOUT || result == 15) {      /* FIXME: 15 ??? */
 214                         if (!maxretry--) {
 215                                 err("read_lcd: maxretry timeout");
 216                                 return -ETIME;
 217                         }
 218                         interruptible_sleep_on_timeout(&lcd->wait_q,
 219                                                        NAK_TIMEOUT);
 220                         continue;
 221                 } else if (result != -EREMOTEIO) {
 222                         err("Read Whoops - result:%u partial:%u this_read:%u",
 223                              result, partial, this_read);
 224                         return -EIO;
 225                 } else {
 226                         return (0);
 227                 }
 228
 229                 if (this_read) {
 230                         if (copy_to_user(buffer, ibuf, this_read))
 231                                 return -EFAULT;
 232                         count -= this_read;
 233                         read_count += this_read;
 234                         buffer += this_read;
 235                 }
 236         }
 237         return read_count;
 238 }
 239
 240 static struct
 241 file_operations usb_lcd_fops = {
 242         .owner =        THIS_MODULE,
 243         .read =         read_lcd,
 244         .write =        write_lcd,
 245         .ioctl =        ioctl_lcd,
 246         .open =         open_lcd,
 247         .release =      close_lcd,
 248 };
 249
 250 static struct usb_class_driver usb_lcd_class = {
 251         .name =         "usb/lcd%d",
 252         .fops =         &usb_lcd_fops,
 253         .mode =         S_IFCHR | S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP,
 254         .minor_base =   USBLCD_MINOR,
 255 };
 256
 257 static int probe_lcd(struct usb_interface *intf, const struct usb_device_id *id)
 258 {
 259         struct usb_device *dev = interface_to_usbdev(intf);
 260         struct lcd_usb_data *lcd = &lcd_instance;
 261         int i;
 262         int retval;
 263
 264         if (le16_to_cpu(dev->descriptor.idProduct) != 0x0001) {
 265                 warn(KERN_INFO "USBLCD model not supported.");
 266                 return -ENODEV;
 267         }
 268
 269         if (lcd->present == 1) {
 270                 warn(KERN_INFO "Multiple USBLCDs are not supported!");
 271                 return -ENODEV;
 272         }
 273
 274         i = le16_to_cpu(dev->descriptor.bcdDevice);
 275
 276         info("USBLCD Version %1d%1d.%1d%1d found at address %d",
 277                 (i & 0xF000)>>12,(i & 0xF00)>>8,(i & 0xF0)>>4,(i & 0xF),
 278                 dev->devnum);
 279
 280
 281
 282         lcd->present = 1;
 283         lcd->lcd_dev = dev;
 284
 285         if (!(lcd->obuf = (char *) kmalloc(OBUF_SIZE, GFP_KERNEL))) {
 286                 err("probe_lcd: Not enough memory for the output buffer");
 287                 return -ENOMEM;
 288         }
 289         dbg("probe_lcd: obuf address:%p", lcd->obuf);
 290
 291         if (!(lcd->ibuf = (char *) kmalloc(IBUF_SIZE, GFP_KERNEL))) {
 292                 err("probe_lcd: Not enough memory for the input buffer");
 293                 kfree(lcd->obuf);
 294                 return -ENOMEM;
 295         }
 296         dbg("probe_lcd: ibuf address:%p", lcd->ibuf);
 297
 298         retval = usb_register_dev(intf, &usb_lcd_class);
 299         if (retval) {
 300                 err("Not able to get a minor for this device.");
 301                 kfree(lcd->obuf);
 302                 kfree(lcd->ibuf);
 303                 return -ENOMEM;
 304         }
 305
 306         usb_set_intfdata (intf, lcd);
 307         return 0;
 308 }
 309
 310 static void disconnect_lcd(struct usb_interface *intf)
 311 {
 312         struct lcd_usb_data *lcd = usb_get_intfdata (intf);
 313
 314         usb_set_intfdata (intf, NULL);
 315         if (lcd) {
 316                 usb_deregister_dev(intf, &usb_lcd_class);
 317
 318                 if (lcd->isopen) {
 319                         lcd->isopen = 0;
 320                         /* better let it finish - the release will do whats needed */
 321                         lcd->lcd_dev = NULL;
 322                         return;
 323                 }
 324                 kfree(lcd->ibuf);
 325                 kfree(lcd->obuf);
 326
 327                 info("USBLCD disconnected.");
 328
 329                 lcd->present = 0;
 330         }
 331 }
 332
 333 static struct usb_device_id id_table [] = {
 334         { .idVendor = 0x10D2, .match_flags = USB_DEVICE_ID_MATCH_VENDOR, },
 335         {},
 336 };
 337
 338 MODULE_DEVICE_TABLE (usb, id_table);
 339
 340 static struct usb_driver lcd_driver = {
 341         .owner =        THIS_MODULE,
 342         .name =         "usblcd",
 343         .probe =        (void *)probe_lcd,
 344         .disconnect =   disconnect_lcd,
 345         .id_table =     id_table,
 346 };
 347
 348 static int __init usb_lcd_init(void)
 349 {
 350         int retval;
 351         retval = usb_register(&lcd_driver);
 352         if (retval)
 353                 goto out;
 354
 355         info("%s (C) Adams IT Services http://www.usblcd.de", DRIVER_VERSION);
 356         info("USBLCD support registered.");
 357 out:
 358         return retval;
 359 }
 360
 361
 362 static void __exit usb_lcd_cleanup(void)
 363 {
 364         struct lcd_usb_data *lcd = &lcd_instance;
 365
 366         lcd->present = 0;
 367         usb_deregister(&lcd_driver);
 368 }
 369
 370 module_init(usb_lcd_init);
 371 module_exit(usb_lcd_cleanup);
 372
 373 MODULE_AUTHOR("Adams IT Services <info@usblcd.de>");
 374 MODULE_DESCRIPTION(DRIVER_VERSION);
 375 MODULE_LICENSE("GPL");