1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Driver for Meywa-Denki & KAYAC YUREX 4 * 5 * Copyright (C) 2010 Tomoki Sekiyama (tomoki.sekiyama@gmail.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/kref.h> 18 #include <linux/mutex.h> 19 #include <linux/uaccess.h> 20 #include <linux/usb.h> 21 #include <linux/hid.h> 22 23 #define DRIVER_AUTHOR "Tomoki Sekiyama" 24 #define DRIVER_DESC "Driver for Meywa-Denki & KAYAC YUREX" 25 26 #define YUREX_VENDOR_ID 0x0c45 27 #define YUREX_PRODUCT_ID 0x1010 28 29 #define CMD_ACK '!' 30 #define CMD_ANIMATE 'A' 31 #define CMD_COUNT 'C' 32 #define CMD_LED 'L' 33 #define CMD_READ 'R' 34 #define CMD_SET 'S' 35 #define CMD_VERSION 'V' 36 #define CMD_EOF 0x0d 37 #define CMD_PADDING 0xff 38 39 #define YUREX_BUF_SIZE 8 40 #define YUREX_WRITE_TIMEOUT (HZ*2) 41 42 /* table of devices that work with this driver */ 43 static struct usb_device_id yurex_table[] = { 44 { USB_DEVICE(YUREX_VENDOR_ID, YUREX_PRODUCT_ID) }, 45 { } /* Terminating entry */ 46 }; 47 MODULE_DEVICE_TABLE(usb, yurex_table); 48 49 #ifdef CONFIG_USB_DYNAMIC_MINORS 50 #define YUREX_MINOR_BASE 0 51 #else 52 #define YUREX_MINOR_BASE 192 53 #endif 54 55 /* Structure to hold all of our device specific stuff */ 56 struct usb_yurex { 57 struct usb_device *udev; 58 struct usb_interface *interface; 59 __u8 int_in_endpointAddr; 60 struct urb *urb; /* URB for interrupt in */ 61 unsigned char *int_buffer; /* buffer for intterupt in */ 62 struct urb *cntl_urb; /* URB for control msg */ 63 struct usb_ctrlrequest *cntl_req; /* req for control msg */ 64 unsigned char *cntl_buffer; /* buffer for control msg */ 65 66 struct kref kref; 67 struct mutex io_mutex; 68 struct fasync_struct *async_queue; 69 wait_queue_head_t waitq; 70 71 spinlock_t lock; 72 __s64 bbu; /* BBU from device */ 73 }; 74 #define to_yurex_dev(d) container_of(d, struct usb_yurex, kref) 75 76 static struct usb_driver yurex_driver; 77 static const struct file_operations yurex_fops; 78 79 80 static void yurex_control_callback(struct urb *urb) 81 { 82 struct usb_yurex *dev = urb->context; 83 int status = urb->status; 84 85 if (status) { 86 dev_err(&urb->dev->dev, "%s - control failed: %d\n", 87 __func__, status); 88 wake_up_interruptible(&dev->waitq); 89 return; 90 } 91 /* on success, sender woken up by CMD_ACK int in, or timeout */ 92 } 93 94 static void yurex_delete(struct kref *kref) 95 { 96 struct usb_yurex *dev = to_yurex_dev(kref); 97 98 dev_dbg(&dev->interface->dev, "%s\n", __func__); 99 100 usb_put_dev(dev->udev); 101 if (dev->cntl_urb) { 102 usb_kill_urb(dev->cntl_urb); 103 kfree(dev->cntl_req); 104 if (dev->cntl_buffer) 105 usb_free_coherent(dev->udev, YUREX_BUF_SIZE, 106 dev->cntl_buffer, dev->cntl_urb->transfer_dma); 107 usb_free_urb(dev->cntl_urb); 108 } 109 if (dev->urb) { 110 usb_kill_urb(dev->urb); 111 if (dev->int_buffer) 112 usb_free_coherent(dev->udev, YUREX_BUF_SIZE, 113 dev->int_buffer, dev->urb->transfer_dma); 114 usb_free_urb(dev->urb); 115 } 116 kfree(dev); 117 } 118 119 /* 120 * usb class driver info in order to get a minor number from the usb core, 121 * and to have the device registered with the driver core 122 */ 123 static struct usb_class_driver yurex_class = { 124 .name = "yurex%d", 125 .fops = &yurex_fops, 126 .minor_base = YUREX_MINOR_BASE, 127 }; 128 129 static void yurex_interrupt(struct urb *urb) 130 { 131 struct usb_yurex *dev = urb->context; 132 unsigned char *buf = dev->int_buffer; 133 int status = urb->status; 134 unsigned long flags; 135 int retval, i; 136 137 switch (status) { 138 case 0: /*success*/ 139 break; 140 case -EOVERFLOW: 141 dev_err(&dev->interface->dev, 142 "%s - overflow with length %d, actual length is %d\n", 143 __func__, YUREX_BUF_SIZE, dev->urb->actual_length); 144 case -ECONNRESET: 145 case -ENOENT: 146 case -ESHUTDOWN: 147 case -EILSEQ: 148 /* The device is terminated, clean up */ 149 return; 150 default: 151 dev_err(&dev->interface->dev, 152 "%s - unknown status received: %d\n", __func__, status); 153 goto exit; 154 } 155 156 /* handle received message */ 157 switch (buf[0]) { 158 case CMD_COUNT: 159 case CMD_READ: 160 if (buf[6] == CMD_EOF) { 161 spin_lock_irqsave(&dev->lock, flags); 162 dev->bbu = 0; 163 for (i = 1; i < 6; i++) { 164 dev->bbu += buf[i]; 165 if (i != 5) 166 dev->bbu <<= 8; 167 } 168 dev_dbg(&dev->interface->dev, "%s count: %lld\n", 169 __func__, dev->bbu); 170 spin_unlock_irqrestore(&dev->lock, flags); 171 172 kill_fasync(&dev->async_queue, SIGIO, POLL_IN); 173 } 174 else 175 dev_dbg(&dev->interface->dev, 176 "data format error - no EOF\n"); 177 break; 178 case CMD_ACK: 179 dev_dbg(&dev->interface->dev, "%s ack: %c\n", 180 __func__, buf[1]); 181 wake_up_interruptible(&dev->waitq); 182 break; 183 } 184 185 exit: 186 retval = usb_submit_urb(dev->urb, GFP_ATOMIC); 187 if (retval) { 188 dev_err(&dev->interface->dev, "%s - usb_submit_urb failed: %d\n", 189 __func__, retval); 190 } 191 } 192 193 static int yurex_probe(struct usb_interface *interface, const struct usb_device_id *id) 194 { 195 struct usb_yurex *dev; 196 struct usb_host_interface *iface_desc; 197 struct usb_endpoint_descriptor *endpoint; 198 int retval = -ENOMEM; 199 DEFINE_WAIT(wait); 200 int res; 201 202 /* allocate memory for our device state and initialize it */ 203 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 204 if (!dev) 205 goto error; 206 kref_init(&dev->kref); 207 mutex_init(&dev->io_mutex); 208 spin_lock_init(&dev->lock); 209 init_waitqueue_head(&dev->waitq); 210 211 dev->udev = usb_get_dev(interface_to_usbdev(interface)); 212 dev->interface = interface; 213 214 /* set up the endpoint information */ 215 iface_desc = interface->cur_altsetting; 216 res = usb_find_int_in_endpoint(iface_desc, &endpoint); 217 if (res) { 218 dev_err(&interface->dev, "Could not find endpoints\n"); 219 retval = res; 220 goto error; 221 } 222 223 dev->int_in_endpointAddr = endpoint->bEndpointAddress; 224 225 /* allocate control URB */ 226 dev->cntl_urb = usb_alloc_urb(0, GFP_KERNEL); 227 if (!dev->cntl_urb) 228 goto error; 229 230 /* allocate buffer for control req */ 231 dev->cntl_req = kmalloc(YUREX_BUF_SIZE, GFP_KERNEL); 232 if (!dev->cntl_req) 233 goto error; 234 235 /* allocate buffer for control msg */ 236 dev->cntl_buffer = usb_alloc_coherent(dev->udev, YUREX_BUF_SIZE, 237 GFP_KERNEL, 238 &dev->cntl_urb->transfer_dma); 239 if (!dev->cntl_buffer) { 240 dev_err(&interface->dev, "Could not allocate cntl_buffer\n"); 241 goto error; 242 } 243 244 /* configure control URB */ 245 dev->cntl_req->bRequestType = USB_DIR_OUT | USB_TYPE_CLASS | 246 USB_RECIP_INTERFACE; 247 dev->cntl_req->bRequest = HID_REQ_SET_REPORT; 248 dev->cntl_req->wValue = cpu_to_le16((HID_OUTPUT_REPORT + 1) << 8); 249 dev->cntl_req->wIndex = cpu_to_le16(iface_desc->desc.bInterfaceNumber); 250 dev->cntl_req->wLength = cpu_to_le16(YUREX_BUF_SIZE); 251 252 usb_fill_control_urb(dev->cntl_urb, dev->udev, 253 usb_sndctrlpipe(dev->udev, 0), 254 (void *)dev->cntl_req, dev->cntl_buffer, 255 YUREX_BUF_SIZE, yurex_control_callback, dev); 256 dev->cntl_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; 257 258 259 /* allocate interrupt URB */ 260 dev->urb = usb_alloc_urb(0, GFP_KERNEL); 261 if (!dev->urb) 262 goto error; 263 264 /* allocate buffer for interrupt in */ 265 dev->int_buffer = usb_alloc_coherent(dev->udev, YUREX_BUF_SIZE, 266 GFP_KERNEL, &dev->urb->transfer_dma); 267 if (!dev->int_buffer) { 268 dev_err(&interface->dev, "Could not allocate int_buffer\n"); 269 goto error; 270 } 271 272 /* configure interrupt URB */ 273 usb_fill_int_urb(dev->urb, dev->udev, 274 usb_rcvintpipe(dev->udev, dev->int_in_endpointAddr), 275 dev->int_buffer, YUREX_BUF_SIZE, yurex_interrupt, 276 dev, 1); 277 dev->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; 278 if (usb_submit_urb(dev->urb, GFP_KERNEL)) { 279 retval = -EIO; 280 dev_err(&interface->dev, "Could not submitting URB\n"); 281 goto error; 282 } 283 284 /* save our data pointer in this interface device */ 285 usb_set_intfdata(interface, dev); 286 dev->bbu = -1; 287 288 /* we can register the device now, as it is ready */ 289 retval = usb_register_dev(interface, &yurex_class); 290 if (retval) { 291 dev_err(&interface->dev, 292 "Not able to get a minor for this device.\n"); 293 usb_set_intfdata(interface, NULL); 294 goto error; 295 } 296 297 dev_info(&interface->dev, 298 "USB YUREX device now attached to Yurex #%d\n", 299 interface->minor); 300 301 return 0; 302 303 error: 304 if (dev) 305 /* this frees allocated memory */ 306 kref_put(&dev->kref, yurex_delete); 307 return retval; 308 } 309 310 static void yurex_disconnect(struct usb_interface *interface) 311 { 312 struct usb_yurex *dev; 313 int minor = interface->minor; 314 315 dev = usb_get_intfdata(interface); 316 usb_set_intfdata(interface, NULL); 317 318 /* give back our minor */ 319 usb_deregister_dev(interface, &yurex_class); 320 321 /* prevent more I/O from starting */ 322 mutex_lock(&dev->io_mutex); 323 dev->interface = NULL; 324 mutex_unlock(&dev->io_mutex); 325 326 /* wakeup waiters */ 327 kill_fasync(&dev->async_queue, SIGIO, POLL_IN); 328 wake_up_interruptible(&dev->waitq); 329 330 /* decrement our usage count */ 331 kref_put(&dev->kref, yurex_delete); 332 333 dev_info(&interface->dev, "USB YUREX #%d now disconnected\n", minor); 334 } 335 336 static struct usb_driver yurex_driver = { 337 .name = "yurex", 338 .probe = yurex_probe, 339 .disconnect = yurex_disconnect, 340 .id_table = yurex_table, 341 }; 342 343 344 static int yurex_fasync(int fd, struct file *file, int on) 345 { 346 struct usb_yurex *dev; 347 348 dev = file->private_data; 349 return fasync_helper(fd, file, on, &dev->async_queue); 350 } 351 352 static int yurex_open(struct inode *inode, struct file *file) 353 { 354 struct usb_yurex *dev; 355 struct usb_interface *interface; 356 int subminor; 357 int retval = 0; 358 359 subminor = iminor(inode); 360 361 interface = usb_find_interface(&yurex_driver, subminor); 362 if (!interface) { 363 printk(KERN_ERR "%s - error, can't find device for minor %d", 364 __func__, subminor); 365 retval = -ENODEV; 366 goto exit; 367 } 368 369 dev = usb_get_intfdata(interface); 370 if (!dev) { 371 retval = -ENODEV; 372 goto exit; 373 } 374 375 /* increment our usage count for the device */ 376 kref_get(&dev->kref); 377 378 /* save our object in the file's private structure */ 379 mutex_lock(&dev->io_mutex); 380 file->private_data = dev; 381 mutex_unlock(&dev->io_mutex); 382 383 exit: 384 return retval; 385 } 386 387 static int yurex_release(struct inode *inode, struct file *file) 388 { 389 struct usb_yurex *dev; 390 391 dev = file->private_data; 392 if (dev == NULL) 393 return -ENODEV; 394 395 /* decrement the count on our device */ 396 kref_put(&dev->kref, yurex_delete); 397 return 0; 398 } 399 400 static ssize_t yurex_read(struct file *file, char __user *buffer, size_t count, 401 loff_t *ppos) 402 { 403 struct usb_yurex *dev; 404 int retval = 0; 405 int bytes_read = 0; 406 char in_buffer[20]; 407 unsigned long flags; 408 409 dev = file->private_data; 410 411 mutex_lock(&dev->io_mutex); 412 if (!dev->interface) { /* already disconnected */ 413 retval = -ENODEV; 414 goto exit; 415 } 416 417 spin_lock_irqsave(&dev->lock, flags); 418 bytes_read = snprintf(in_buffer, 20, "%lld\n", dev->bbu); 419 spin_unlock_irqrestore(&dev->lock, flags); 420 421 if (*ppos < bytes_read) { 422 if (copy_to_user(buffer, in_buffer + *ppos, bytes_read - *ppos)) 423 retval = -EFAULT; 424 else { 425 retval = bytes_read - *ppos; 426 *ppos += bytes_read; 427 } 428 } 429 430 exit: 431 mutex_unlock(&dev->io_mutex); 432 return retval; 433 } 434 435 static ssize_t yurex_write(struct file *file, const char __user *user_buffer, 436 size_t count, loff_t *ppos) 437 { 438 struct usb_yurex *dev; 439 int i, set = 0, retval = 0; 440 char buffer[16]; 441 char *data = buffer; 442 unsigned long long c, c2 = 0; 443 signed long timeout = 0; 444 DEFINE_WAIT(wait); 445 446 count = min(sizeof(buffer), count); 447 dev = file->private_data; 448 449 /* verify that we actually have some data to write */ 450 if (count == 0) 451 goto error; 452 453 mutex_lock(&dev->io_mutex); 454 if (!dev->interface) { /* already disconnected */ 455 mutex_unlock(&dev->io_mutex); 456 retval = -ENODEV; 457 goto error; 458 } 459 460 if (copy_from_user(buffer, user_buffer, count)) { 461 mutex_unlock(&dev->io_mutex); 462 retval = -EFAULT; 463 goto error; 464 } 465 memset(dev->cntl_buffer, CMD_PADDING, YUREX_BUF_SIZE); 466 467 switch (buffer[0]) { 468 case CMD_ANIMATE: 469 case CMD_LED: 470 dev->cntl_buffer[0] = buffer[0]; 471 dev->cntl_buffer[1] = buffer[1]; 472 dev->cntl_buffer[2] = CMD_EOF; 473 break; 474 case CMD_READ: 475 case CMD_VERSION: 476 dev->cntl_buffer[0] = buffer[0]; 477 dev->cntl_buffer[1] = 0x00; 478 dev->cntl_buffer[2] = CMD_EOF; 479 break; 480 case CMD_SET: 481 data++; 482 /* FALL THROUGH */ 483 case '0' ... '9': 484 set = 1; 485 c = c2 = simple_strtoull(data, NULL, 0); 486 dev->cntl_buffer[0] = CMD_SET; 487 for (i = 1; i < 6; i++) { 488 dev->cntl_buffer[i] = (c>>32) & 0xff; 489 c <<= 8; 490 } 491 buffer[6] = CMD_EOF; 492 break; 493 default: 494 mutex_unlock(&dev->io_mutex); 495 return -EINVAL; 496 } 497 498 /* send the data as the control msg */ 499 prepare_to_wait(&dev->waitq, &wait, TASK_INTERRUPTIBLE); 500 dev_dbg(&dev->interface->dev, "%s - submit %c\n", __func__, 501 dev->cntl_buffer[0]); 502 retval = usb_submit_urb(dev->cntl_urb, GFP_KERNEL); 503 if (retval >= 0) 504 timeout = schedule_timeout(YUREX_WRITE_TIMEOUT); 505 finish_wait(&dev->waitq, &wait); 506 507 mutex_unlock(&dev->io_mutex); 508 509 if (retval < 0) { 510 dev_err(&dev->interface->dev, 511 "%s - failed to send bulk msg, error %d\n", 512 __func__, retval); 513 goto error; 514 } 515 if (set && timeout) 516 dev->bbu = c2; 517 return timeout ? count : -EIO; 518 519 error: 520 return retval; 521 } 522 523 static const struct file_operations yurex_fops = { 524 .owner = THIS_MODULE, 525 .read = yurex_read, 526 .write = yurex_write, 527 .open = yurex_open, 528 .release = yurex_release, 529 .fasync = yurex_fasync, 530 .llseek = default_llseek, 531 }; 532 533 module_usb_driver(yurex_driver); 534 535 MODULE_LICENSE("GPL"); 536