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 8 #include <linux/kernel.h> 9 #include <linux/errno.h> 10 #include <linux/slab.h> 11 #include <linux/module.h> 12 #include <linux/kref.h> 13 #include <linux/mutex.h> 14 #include <linux/uaccess.h> 15 #include <linux/usb.h> 16 #include <linux/hid.h> 17 18 #define DRIVER_AUTHOR "Tomoki Sekiyama" 19 #define DRIVER_DESC "Driver for Meywa-Denki & KAYAC YUREX" 20 21 #define YUREX_VENDOR_ID 0x0c45 22 #define YUREX_PRODUCT_ID 0x1010 23 24 #define CMD_ACK '!' 25 #define CMD_ANIMATE 'A' 26 #define CMD_COUNT 'C' 27 #define CMD_LED 'L' 28 #define CMD_READ 'R' 29 #define CMD_SET 'S' 30 #define CMD_VERSION 'V' 31 #define CMD_EOF 0x0d 32 #define CMD_PADDING 0xff 33 34 #define YUREX_BUF_SIZE 8 35 #define YUREX_WRITE_TIMEOUT (HZ*2) 36 37 /* table of devices that work with this driver */ 38 static struct usb_device_id yurex_table[] = { 39 { USB_DEVICE(YUREX_VENDOR_ID, YUREX_PRODUCT_ID) }, 40 { } /* Terminating entry */ 41 }; 42 MODULE_DEVICE_TABLE(usb, yurex_table); 43 44 #ifdef CONFIG_USB_DYNAMIC_MINORS 45 #define YUREX_MINOR_BASE 0 46 #else 47 #define YUREX_MINOR_BASE 192 48 #endif 49 50 /* Structure to hold all of our device specific stuff */ 51 struct usb_yurex { 52 struct usb_device *udev; 53 struct usb_interface *interface; 54 __u8 int_in_endpointAddr; 55 struct urb *urb; /* URB for interrupt in */ 56 unsigned char *int_buffer; /* buffer for intterupt in */ 57 struct urb *cntl_urb; /* URB for control msg */ 58 struct usb_ctrlrequest *cntl_req; /* req for control msg */ 59 unsigned char *cntl_buffer; /* buffer for control msg */ 60 61 struct kref kref; 62 struct mutex io_mutex; 63 struct fasync_struct *async_queue; 64 wait_queue_head_t waitq; 65 66 spinlock_t lock; 67 __s64 bbu; /* BBU from device */ 68 }; 69 #define to_yurex_dev(d) container_of(d, struct usb_yurex, kref) 70 71 static struct usb_driver yurex_driver; 72 static const struct file_operations yurex_fops; 73 74 75 static void yurex_control_callback(struct urb *urb) 76 { 77 struct usb_yurex *dev = urb->context; 78 int status = urb->status; 79 80 if (status) { 81 dev_err(&urb->dev->dev, "%s - control failed: %d\n", 82 __func__, status); 83 wake_up_interruptible(&dev->waitq); 84 return; 85 } 86 /* on success, sender woken up by CMD_ACK int in, or timeout */ 87 } 88 89 static void yurex_delete(struct kref *kref) 90 { 91 struct usb_yurex *dev = to_yurex_dev(kref); 92 93 dev_dbg(&dev->interface->dev, "%s\n", __func__); 94 95 if (dev->cntl_urb) { 96 usb_kill_urb(dev->cntl_urb); 97 kfree(dev->cntl_req); 98 if (dev->cntl_buffer) 99 usb_free_coherent(dev->udev, YUREX_BUF_SIZE, 100 dev->cntl_buffer, dev->cntl_urb->transfer_dma); 101 usb_free_urb(dev->cntl_urb); 102 } 103 if (dev->urb) { 104 usb_kill_urb(dev->urb); 105 if (dev->int_buffer) 106 usb_free_coherent(dev->udev, YUREX_BUF_SIZE, 107 dev->int_buffer, dev->urb->transfer_dma); 108 usb_free_urb(dev->urb); 109 } 110 usb_put_dev(dev->udev); 111 kfree(dev); 112 } 113 114 /* 115 * usb class driver info in order to get a minor number from the usb core, 116 * and to have the device registered with the driver core 117 */ 118 static struct usb_class_driver yurex_class = { 119 .name = "yurex%d", 120 .fops = &yurex_fops, 121 .minor_base = YUREX_MINOR_BASE, 122 }; 123 124 static void yurex_interrupt(struct urb *urb) 125 { 126 struct usb_yurex *dev = urb->context; 127 unsigned char *buf = dev->int_buffer; 128 int status = urb->status; 129 unsigned long flags; 130 int retval, i; 131 132 switch (status) { 133 case 0: /*success*/ 134 break; 135 case -EOVERFLOW: 136 dev_err(&dev->interface->dev, 137 "%s - overflow with length %d, actual length is %d\n", 138 __func__, YUREX_BUF_SIZE, dev->urb->actual_length); 139 case -ECONNRESET: 140 case -ENOENT: 141 case -ESHUTDOWN: 142 case -EILSEQ: 143 /* The device is terminated, clean up */ 144 return; 145 default: 146 dev_err(&dev->interface->dev, 147 "%s - unknown status received: %d\n", __func__, status); 148 goto exit; 149 } 150 151 /* handle received message */ 152 switch (buf[0]) { 153 case CMD_COUNT: 154 case CMD_READ: 155 if (buf[6] == CMD_EOF) { 156 spin_lock_irqsave(&dev->lock, flags); 157 dev->bbu = 0; 158 for (i = 1; i < 6; i++) { 159 dev->bbu += buf[i]; 160 if (i != 5) 161 dev->bbu <<= 8; 162 } 163 dev_dbg(&dev->interface->dev, "%s count: %lld\n", 164 __func__, dev->bbu); 165 spin_unlock_irqrestore(&dev->lock, flags); 166 167 kill_fasync(&dev->async_queue, SIGIO, POLL_IN); 168 } 169 else 170 dev_dbg(&dev->interface->dev, 171 "data format error - no EOF\n"); 172 break; 173 case CMD_ACK: 174 dev_dbg(&dev->interface->dev, "%s ack: %c\n", 175 __func__, buf[1]); 176 wake_up_interruptible(&dev->waitq); 177 break; 178 } 179 180 exit: 181 retval = usb_submit_urb(dev->urb, GFP_ATOMIC); 182 if (retval) { 183 dev_err(&dev->interface->dev, "%s - usb_submit_urb failed: %d\n", 184 __func__, retval); 185 } 186 } 187 188 static int yurex_probe(struct usb_interface *interface, const struct usb_device_id *id) 189 { 190 struct usb_yurex *dev; 191 struct usb_host_interface *iface_desc; 192 struct usb_endpoint_descriptor *endpoint; 193 int retval = -ENOMEM; 194 DEFINE_WAIT(wait); 195 int res; 196 197 /* allocate memory for our device state and initialize it */ 198 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 199 if (!dev) 200 goto error; 201 kref_init(&dev->kref); 202 mutex_init(&dev->io_mutex); 203 spin_lock_init(&dev->lock); 204 init_waitqueue_head(&dev->waitq); 205 206 dev->udev = usb_get_dev(interface_to_usbdev(interface)); 207 dev->interface = interface; 208 209 /* set up the endpoint information */ 210 iface_desc = interface->cur_altsetting; 211 res = usb_find_int_in_endpoint(iface_desc, &endpoint); 212 if (res) { 213 dev_err(&interface->dev, "Could not find endpoints\n"); 214 retval = res; 215 goto error; 216 } 217 218 dev->int_in_endpointAddr = endpoint->bEndpointAddress; 219 220 /* allocate control URB */ 221 dev->cntl_urb = usb_alloc_urb(0, GFP_KERNEL); 222 if (!dev->cntl_urb) 223 goto error; 224 225 /* allocate buffer for control req */ 226 dev->cntl_req = kmalloc(YUREX_BUF_SIZE, GFP_KERNEL); 227 if (!dev->cntl_req) 228 goto error; 229 230 /* allocate buffer for control msg */ 231 dev->cntl_buffer = usb_alloc_coherent(dev->udev, YUREX_BUF_SIZE, 232 GFP_KERNEL, 233 &dev->cntl_urb->transfer_dma); 234 if (!dev->cntl_buffer) { 235 dev_err(&interface->dev, "Could not allocate cntl_buffer\n"); 236 goto error; 237 } 238 239 /* configure control URB */ 240 dev->cntl_req->bRequestType = USB_DIR_OUT | USB_TYPE_CLASS | 241 USB_RECIP_INTERFACE; 242 dev->cntl_req->bRequest = HID_REQ_SET_REPORT; 243 dev->cntl_req->wValue = cpu_to_le16((HID_OUTPUT_REPORT + 1) << 8); 244 dev->cntl_req->wIndex = cpu_to_le16(iface_desc->desc.bInterfaceNumber); 245 dev->cntl_req->wLength = cpu_to_le16(YUREX_BUF_SIZE); 246 247 usb_fill_control_urb(dev->cntl_urb, dev->udev, 248 usb_sndctrlpipe(dev->udev, 0), 249 (void *)dev->cntl_req, dev->cntl_buffer, 250 YUREX_BUF_SIZE, yurex_control_callback, dev); 251 dev->cntl_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; 252 253 254 /* allocate interrupt URB */ 255 dev->urb = usb_alloc_urb(0, GFP_KERNEL); 256 if (!dev->urb) 257 goto error; 258 259 /* allocate buffer for interrupt in */ 260 dev->int_buffer = usb_alloc_coherent(dev->udev, YUREX_BUF_SIZE, 261 GFP_KERNEL, &dev->urb->transfer_dma); 262 if (!dev->int_buffer) { 263 dev_err(&interface->dev, "Could not allocate int_buffer\n"); 264 goto error; 265 } 266 267 /* configure interrupt URB */ 268 usb_fill_int_urb(dev->urb, dev->udev, 269 usb_rcvintpipe(dev->udev, dev->int_in_endpointAddr), 270 dev->int_buffer, YUREX_BUF_SIZE, yurex_interrupt, 271 dev, 1); 272 dev->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; 273 if (usb_submit_urb(dev->urb, GFP_KERNEL)) { 274 retval = -EIO; 275 dev_err(&interface->dev, "Could not submitting URB\n"); 276 goto error; 277 } 278 279 /* save our data pointer in this interface device */ 280 usb_set_intfdata(interface, dev); 281 dev->bbu = -1; 282 283 /* we can register the device now, as it is ready */ 284 retval = usb_register_dev(interface, &yurex_class); 285 if (retval) { 286 dev_err(&interface->dev, 287 "Not able to get a minor for this device.\n"); 288 usb_set_intfdata(interface, NULL); 289 goto error; 290 } 291 292 dev_info(&interface->dev, 293 "USB YUREX device now attached to Yurex #%d\n", 294 interface->minor); 295 296 return 0; 297 298 error: 299 if (dev) 300 /* this frees allocated memory */ 301 kref_put(&dev->kref, yurex_delete); 302 return retval; 303 } 304 305 static void yurex_disconnect(struct usb_interface *interface) 306 { 307 struct usb_yurex *dev; 308 int minor = interface->minor; 309 310 dev = usb_get_intfdata(interface); 311 usb_set_intfdata(interface, NULL); 312 313 /* give back our minor */ 314 usb_deregister_dev(interface, &yurex_class); 315 316 /* prevent more I/O from starting */ 317 usb_poison_urb(dev->urb); 318 mutex_lock(&dev->io_mutex); 319 dev->interface = NULL; 320 mutex_unlock(&dev->io_mutex); 321 322 /* wakeup waiters */ 323 kill_fasync(&dev->async_queue, SIGIO, POLL_IN); 324 wake_up_interruptible(&dev->waitq); 325 326 /* decrement our usage count */ 327 kref_put(&dev->kref, yurex_delete); 328 329 dev_info(&interface->dev, "USB YUREX #%d now disconnected\n", minor); 330 } 331 332 static struct usb_driver yurex_driver = { 333 .name = "yurex", 334 .probe = yurex_probe, 335 .disconnect = yurex_disconnect, 336 .id_table = yurex_table, 337 }; 338 339 340 static int yurex_fasync(int fd, struct file *file, int on) 341 { 342 struct usb_yurex *dev; 343 344 dev = file->private_data; 345 return fasync_helper(fd, file, on, &dev->async_queue); 346 } 347 348 static int yurex_open(struct inode *inode, struct file *file) 349 { 350 struct usb_yurex *dev; 351 struct usb_interface *interface; 352 int subminor; 353 int retval = 0; 354 355 subminor = iminor(inode); 356 357 interface = usb_find_interface(&yurex_driver, subminor); 358 if (!interface) { 359 printk(KERN_ERR "%s - error, can't find device for minor %d", 360 __func__, subminor); 361 retval = -ENODEV; 362 goto exit; 363 } 364 365 dev = usb_get_intfdata(interface); 366 if (!dev) { 367 retval = -ENODEV; 368 goto exit; 369 } 370 371 /* increment our usage count for the device */ 372 kref_get(&dev->kref); 373 374 /* save our object in the file's private structure */ 375 mutex_lock(&dev->io_mutex); 376 file->private_data = dev; 377 mutex_unlock(&dev->io_mutex); 378 379 exit: 380 return retval; 381 } 382 383 static int yurex_release(struct inode *inode, struct file *file) 384 { 385 struct usb_yurex *dev; 386 387 dev = file->private_data; 388 if (dev == NULL) 389 return -ENODEV; 390 391 /* decrement the count on our device */ 392 kref_put(&dev->kref, yurex_delete); 393 return 0; 394 } 395 396 static ssize_t yurex_read(struct file *file, char __user *buffer, size_t count, 397 loff_t *ppos) 398 { 399 struct usb_yurex *dev; 400 int len = 0; 401 char in_buffer[20]; 402 unsigned long flags; 403 404 dev = file->private_data; 405 406 mutex_lock(&dev->io_mutex); 407 if (!dev->interface) { /* already disconnected */ 408 mutex_unlock(&dev->io_mutex); 409 return -ENODEV; 410 } 411 412 spin_lock_irqsave(&dev->lock, flags); 413 len = snprintf(in_buffer, 20, "%lld\n", dev->bbu); 414 spin_unlock_irqrestore(&dev->lock, flags); 415 mutex_unlock(&dev->io_mutex); 416 417 if (WARN_ON_ONCE(len >= sizeof(in_buffer))) 418 return -EIO; 419 420 return simple_read_from_buffer(buffer, count, ppos, in_buffer, len); 421 } 422 423 static ssize_t yurex_write(struct file *file, const char __user *user_buffer, 424 size_t count, loff_t *ppos) 425 { 426 struct usb_yurex *dev; 427 int i, set = 0, retval = 0; 428 char buffer[16 + 1]; 429 char *data = buffer; 430 unsigned long long c, c2 = 0; 431 signed long timeout = 0; 432 DEFINE_WAIT(wait); 433 434 count = min(sizeof(buffer) - 1, count); 435 dev = file->private_data; 436 437 /* verify that we actually have some data to write */ 438 if (count == 0) 439 goto error; 440 441 mutex_lock(&dev->io_mutex); 442 if (!dev->interface) { /* already disconnected */ 443 mutex_unlock(&dev->io_mutex); 444 retval = -ENODEV; 445 goto error; 446 } 447 448 if (copy_from_user(buffer, user_buffer, count)) { 449 mutex_unlock(&dev->io_mutex); 450 retval = -EFAULT; 451 goto error; 452 } 453 buffer[count] = 0; 454 memset(dev->cntl_buffer, CMD_PADDING, YUREX_BUF_SIZE); 455 456 switch (buffer[0]) { 457 case CMD_ANIMATE: 458 case CMD_LED: 459 dev->cntl_buffer[0] = buffer[0]; 460 dev->cntl_buffer[1] = buffer[1]; 461 dev->cntl_buffer[2] = CMD_EOF; 462 break; 463 case CMD_READ: 464 case CMD_VERSION: 465 dev->cntl_buffer[0] = buffer[0]; 466 dev->cntl_buffer[1] = 0x00; 467 dev->cntl_buffer[2] = CMD_EOF; 468 break; 469 case CMD_SET: 470 data++; 471 /* FALL THROUGH */ 472 case '0' ... '9': 473 set = 1; 474 c = c2 = simple_strtoull(data, NULL, 0); 475 dev->cntl_buffer[0] = CMD_SET; 476 for (i = 1; i < 6; i++) { 477 dev->cntl_buffer[i] = (c>>32) & 0xff; 478 c <<= 8; 479 } 480 buffer[6] = CMD_EOF; 481 break; 482 default: 483 mutex_unlock(&dev->io_mutex); 484 return -EINVAL; 485 } 486 487 /* send the data as the control msg */ 488 prepare_to_wait(&dev->waitq, &wait, TASK_INTERRUPTIBLE); 489 dev_dbg(&dev->interface->dev, "%s - submit %c\n", __func__, 490 dev->cntl_buffer[0]); 491 retval = usb_submit_urb(dev->cntl_urb, GFP_KERNEL); 492 if (retval >= 0) 493 timeout = schedule_timeout(YUREX_WRITE_TIMEOUT); 494 finish_wait(&dev->waitq, &wait); 495 496 mutex_unlock(&dev->io_mutex); 497 498 if (retval < 0) { 499 dev_err(&dev->interface->dev, 500 "%s - failed to send bulk msg, error %d\n", 501 __func__, retval); 502 goto error; 503 } 504 if (set && timeout) 505 dev->bbu = c2; 506 return timeout ? count : -EIO; 507 508 error: 509 return retval; 510 } 511 512 static const struct file_operations yurex_fops = { 513 .owner = THIS_MODULE, 514 .read = yurex_read, 515 .write = yurex_write, 516 .open = yurex_open, 517 .release = yurex_release, 518 .fasync = yurex_fasync, 519 .llseek = default_llseek, 520 }; 521 522 module_usb_driver(yurex_driver); 523 524 MODULE_LICENSE("GPL"); 525