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 unsigned long disconnected:1; 64 struct fasync_struct *async_queue; 65 wait_queue_head_t waitq; 66 67 spinlock_t lock; 68 __s64 bbu; /* BBU from device */ 69 }; 70 #define to_yurex_dev(d) container_of(d, struct usb_yurex, kref) 71 72 static struct usb_driver yurex_driver; 73 static const struct file_operations yurex_fops; 74 75 76 static void yurex_control_callback(struct urb *urb) 77 { 78 struct usb_yurex *dev = urb->context; 79 int status = urb->status; 80 81 if (status) { 82 dev_err(&urb->dev->dev, "%s - control failed: %d\n", 83 __func__, status); 84 wake_up_interruptible(&dev->waitq); 85 return; 86 } 87 /* on success, sender woken up by CMD_ACK int in, or timeout */ 88 } 89 90 static void yurex_delete(struct kref *kref) 91 { 92 struct usb_yurex *dev = to_yurex_dev(kref); 93 94 dev_dbg(&dev->interface->dev, "%s\n", __func__); 95 96 if (dev->cntl_urb) { 97 usb_kill_urb(dev->cntl_urb); 98 kfree(dev->cntl_req); 99 if (dev->cntl_buffer) 100 usb_free_coherent(dev->udev, YUREX_BUF_SIZE, 101 dev->cntl_buffer, dev->cntl_urb->transfer_dma); 102 usb_free_urb(dev->cntl_urb); 103 } 104 if (dev->urb) { 105 usb_kill_urb(dev->urb); 106 if (dev->int_buffer) 107 usb_free_coherent(dev->udev, YUREX_BUF_SIZE, 108 dev->int_buffer, dev->urb->transfer_dma); 109 usb_free_urb(dev->urb); 110 } 111 usb_put_intf(dev->interface); 112 usb_put_dev(dev->udev); 113 kfree(dev); 114 } 115 116 /* 117 * usb class driver info in order to get a minor number from the usb core, 118 * and to have the device registered with the driver core 119 */ 120 static struct usb_class_driver yurex_class = { 121 .name = "yurex%d", 122 .fops = &yurex_fops, 123 .minor_base = YUREX_MINOR_BASE, 124 }; 125 126 static void yurex_interrupt(struct urb *urb) 127 { 128 struct usb_yurex *dev = urb->context; 129 unsigned char *buf = dev->int_buffer; 130 int status = urb->status; 131 unsigned long flags; 132 int retval, i; 133 134 switch (status) { 135 case 0: /*success*/ 136 break; 137 /* The device is terminated or messed up, give up */ 138 case -EOVERFLOW: 139 dev_err(&dev->interface->dev, 140 "%s - overflow with length %d, actual length is %d\n", 141 __func__, YUREX_BUF_SIZE, dev->urb->actual_length); 142 case -ECONNRESET: 143 case -ENOENT: 144 case -ESHUTDOWN: 145 case -EILSEQ: 146 case -EPROTO: 147 case -ETIME: 148 return; 149 default: 150 dev_err(&dev->interface->dev, 151 "%s - unknown status received: %d\n", __func__, status); 152 return; 153 } 154 155 /* handle received message */ 156 switch (buf[0]) { 157 case CMD_COUNT: 158 case CMD_READ: 159 if (buf[6] == CMD_EOF) { 160 spin_lock_irqsave(&dev->lock, flags); 161 dev->bbu = 0; 162 for (i = 1; i < 6; i++) { 163 dev->bbu += buf[i]; 164 if (i != 5) 165 dev->bbu <<= 8; 166 } 167 dev_dbg(&dev->interface->dev, "%s count: %lld\n", 168 __func__, dev->bbu); 169 spin_unlock_irqrestore(&dev->lock, flags); 170 171 kill_fasync(&dev->async_queue, SIGIO, POLL_IN); 172 } 173 else 174 dev_dbg(&dev->interface->dev, 175 "data format error - no EOF\n"); 176 break; 177 case CMD_ACK: 178 dev_dbg(&dev->interface->dev, "%s ack: %c\n", 179 __func__, buf[1]); 180 wake_up_interruptible(&dev->waitq); 181 break; 182 } 183 184 retval = usb_submit_urb(dev->urb, GFP_ATOMIC); 185 if (retval) { 186 dev_err(&dev->interface->dev, "%s - usb_submit_urb failed: %d\n", 187 __func__, retval); 188 } 189 } 190 191 static int yurex_probe(struct usb_interface *interface, const struct usb_device_id *id) 192 { 193 struct usb_yurex *dev; 194 struct usb_host_interface *iface_desc; 195 struct usb_endpoint_descriptor *endpoint; 196 int retval = -ENOMEM; 197 DEFINE_WAIT(wait); 198 int res; 199 200 /* allocate memory for our device state and initialize it */ 201 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 202 if (!dev) 203 goto error; 204 kref_init(&dev->kref); 205 mutex_init(&dev->io_mutex); 206 spin_lock_init(&dev->lock); 207 init_waitqueue_head(&dev->waitq); 208 209 dev->udev = usb_get_dev(interface_to_usbdev(interface)); 210 dev->interface = usb_get_intf(interface); 211 212 /* set up the endpoint information */ 213 iface_desc = interface->cur_altsetting; 214 res = usb_find_int_in_endpoint(iface_desc, &endpoint); 215 if (res) { 216 dev_err(&interface->dev, "Could not find endpoints\n"); 217 retval = res; 218 goto error; 219 } 220 221 dev->int_in_endpointAddr = endpoint->bEndpointAddress; 222 223 /* allocate control URB */ 224 dev->cntl_urb = usb_alloc_urb(0, GFP_KERNEL); 225 if (!dev->cntl_urb) 226 goto error; 227 228 /* allocate buffer for control req */ 229 dev->cntl_req = kmalloc(YUREX_BUF_SIZE, GFP_KERNEL); 230 if (!dev->cntl_req) 231 goto error; 232 233 /* allocate buffer for control msg */ 234 dev->cntl_buffer = usb_alloc_coherent(dev->udev, YUREX_BUF_SIZE, 235 GFP_KERNEL, 236 &dev->cntl_urb->transfer_dma); 237 if (!dev->cntl_buffer) { 238 dev_err(&interface->dev, "Could not allocate cntl_buffer\n"); 239 goto error; 240 } 241 242 /* configure control URB */ 243 dev->cntl_req->bRequestType = USB_DIR_OUT | USB_TYPE_CLASS | 244 USB_RECIP_INTERFACE; 245 dev->cntl_req->bRequest = HID_REQ_SET_REPORT; 246 dev->cntl_req->wValue = cpu_to_le16((HID_OUTPUT_REPORT + 1) << 8); 247 dev->cntl_req->wIndex = cpu_to_le16(iface_desc->desc.bInterfaceNumber); 248 dev->cntl_req->wLength = cpu_to_le16(YUREX_BUF_SIZE); 249 250 usb_fill_control_urb(dev->cntl_urb, dev->udev, 251 usb_sndctrlpipe(dev->udev, 0), 252 (void *)dev->cntl_req, dev->cntl_buffer, 253 YUREX_BUF_SIZE, yurex_control_callback, dev); 254 dev->cntl_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; 255 256 257 /* allocate interrupt URB */ 258 dev->urb = usb_alloc_urb(0, GFP_KERNEL); 259 if (!dev->urb) 260 goto error; 261 262 /* allocate buffer for interrupt in */ 263 dev->int_buffer = usb_alloc_coherent(dev->udev, YUREX_BUF_SIZE, 264 GFP_KERNEL, &dev->urb->transfer_dma); 265 if (!dev->int_buffer) { 266 dev_err(&interface->dev, "Could not allocate int_buffer\n"); 267 goto error; 268 } 269 270 /* configure interrupt URB */ 271 usb_fill_int_urb(dev->urb, dev->udev, 272 usb_rcvintpipe(dev->udev, dev->int_in_endpointAddr), 273 dev->int_buffer, YUREX_BUF_SIZE, yurex_interrupt, 274 dev, 1); 275 dev->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; 276 if (usb_submit_urb(dev->urb, GFP_KERNEL)) { 277 retval = -EIO; 278 dev_err(&interface->dev, "Could not submitting URB\n"); 279 goto error; 280 } 281 282 /* save our data pointer in this interface device */ 283 usb_set_intfdata(interface, dev); 284 dev->bbu = -1; 285 286 /* we can register the device now, as it is ready */ 287 retval = usb_register_dev(interface, &yurex_class); 288 if (retval) { 289 dev_err(&interface->dev, 290 "Not able to get a minor for this device.\n"); 291 usb_set_intfdata(interface, NULL); 292 goto error; 293 } 294 295 dev_info(&interface->dev, 296 "USB YUREX device now attached to Yurex #%d\n", 297 interface->minor); 298 299 return 0; 300 301 error: 302 if (dev) 303 /* this frees allocated memory */ 304 kref_put(&dev->kref, yurex_delete); 305 return retval; 306 } 307 308 static void yurex_disconnect(struct usb_interface *interface) 309 { 310 struct usb_yurex *dev; 311 int minor = interface->minor; 312 313 dev = usb_get_intfdata(interface); 314 usb_set_intfdata(interface, NULL); 315 316 /* give back our minor */ 317 usb_deregister_dev(interface, &yurex_class); 318 319 /* prevent more I/O from starting */ 320 usb_poison_urb(dev->urb); 321 usb_poison_urb(dev->cntl_urb); 322 mutex_lock(&dev->io_mutex); 323 dev->disconnected = 1; 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 len = 0; 405 char in_buffer[20]; 406 unsigned long flags; 407 408 dev = file->private_data; 409 410 mutex_lock(&dev->io_mutex); 411 if (dev->disconnected) { /* already disconnected */ 412 mutex_unlock(&dev->io_mutex); 413 return -ENODEV; 414 } 415 416 spin_lock_irqsave(&dev->lock, flags); 417 len = snprintf(in_buffer, 20, "%lld\n", dev->bbu); 418 spin_unlock_irqrestore(&dev->lock, flags); 419 mutex_unlock(&dev->io_mutex); 420 421 if (WARN_ON_ONCE(len >= sizeof(in_buffer))) 422 return -EIO; 423 424 return simple_read_from_buffer(buffer, count, ppos, in_buffer, len); 425 } 426 427 static ssize_t yurex_write(struct file *file, const char __user *user_buffer, 428 size_t count, loff_t *ppos) 429 { 430 struct usb_yurex *dev; 431 int i, set = 0, retval = 0; 432 char buffer[16 + 1]; 433 char *data = buffer; 434 unsigned long long c, c2 = 0; 435 signed long timeout = 0; 436 DEFINE_WAIT(wait); 437 438 count = min(sizeof(buffer) - 1, count); 439 dev = file->private_data; 440 441 /* verify that we actually have some data to write */ 442 if (count == 0) 443 goto error; 444 445 mutex_lock(&dev->io_mutex); 446 if (dev->disconnected) { /* already disconnected */ 447 mutex_unlock(&dev->io_mutex); 448 retval = -ENODEV; 449 goto error; 450 } 451 452 if (copy_from_user(buffer, user_buffer, count)) { 453 mutex_unlock(&dev->io_mutex); 454 retval = -EFAULT; 455 goto error; 456 } 457 buffer[count] = 0; 458 memset(dev->cntl_buffer, CMD_PADDING, YUREX_BUF_SIZE); 459 460 switch (buffer[0]) { 461 case CMD_ANIMATE: 462 case CMD_LED: 463 dev->cntl_buffer[0] = buffer[0]; 464 dev->cntl_buffer[1] = buffer[1]; 465 dev->cntl_buffer[2] = CMD_EOF; 466 break; 467 case CMD_READ: 468 case CMD_VERSION: 469 dev->cntl_buffer[0] = buffer[0]; 470 dev->cntl_buffer[1] = 0x00; 471 dev->cntl_buffer[2] = CMD_EOF; 472 break; 473 case CMD_SET: 474 data++; 475 fallthrough; 476 case '0' ... '9': 477 set = 1; 478 c = c2 = simple_strtoull(data, NULL, 0); 479 dev->cntl_buffer[0] = CMD_SET; 480 for (i = 1; i < 6; i++) { 481 dev->cntl_buffer[i] = (c>>32) & 0xff; 482 c <<= 8; 483 } 484 buffer[6] = CMD_EOF; 485 break; 486 default: 487 mutex_unlock(&dev->io_mutex); 488 return -EINVAL; 489 } 490 491 /* send the data as the control msg */ 492 prepare_to_wait(&dev->waitq, &wait, TASK_INTERRUPTIBLE); 493 dev_dbg(&dev->interface->dev, "%s - submit %c\n", __func__, 494 dev->cntl_buffer[0]); 495 retval = usb_submit_urb(dev->cntl_urb, GFP_KERNEL); 496 if (retval >= 0) 497 timeout = schedule_timeout(YUREX_WRITE_TIMEOUT); 498 finish_wait(&dev->waitq, &wait); 499 500 mutex_unlock(&dev->io_mutex); 501 502 if (retval < 0) { 503 dev_err(&dev->interface->dev, 504 "%s - failed to send bulk msg, error %d\n", 505 __func__, retval); 506 goto error; 507 } 508 if (set && timeout) 509 dev->bbu = c2; 510 return timeout ? count : -EIO; 511 512 error: 513 return retval; 514 } 515 516 static const struct file_operations yurex_fops = { 517 .owner = THIS_MODULE, 518 .read = yurex_read, 519 .write = yurex_write, 520 .open = yurex_open, 521 .release = yurex_release, 522 .fasync = yurex_fasync, 523 .llseek = default_llseek, 524 }; 525 526 module_usb_driver(yurex_driver); 527 528 MODULE_LICENSE("GPL"); 529