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(urb: dev->cntl_urb); |
98 | kfree(objp: dev->cntl_req); |
99 | usb_free_coherent(dev: dev->udev, YUREX_BUF_SIZE, |
100 | addr: dev->cntl_buffer, dma: dev->cntl_urb->transfer_dma); |
101 | usb_free_urb(urb: dev->cntl_urb); |
102 | } |
103 | if (dev->urb) { |
104 | usb_kill_urb(urb: dev->urb); |
105 | usb_free_coherent(dev: dev->udev, YUREX_BUF_SIZE, |
106 | addr: dev->int_buffer, dma: dev->urb->transfer_dma); |
107 | usb_free_urb(urb: dev->urb); |
108 | } |
109 | usb_put_intf(intf: dev->interface); |
110 | usb_put_dev(dev: dev->udev); |
111 | kfree(objp: 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 | /* The device is terminated or messed up, give up */ |
136 | case -EOVERFLOW: |
137 | dev_err(&dev->interface->dev, |
138 | "%s - overflow with length %d, actual length is %d\n" , |
139 | __func__, YUREX_BUF_SIZE, dev->urb->actual_length); |
140 | return; |
141 | case -ECONNRESET: |
142 | case -ENOENT: |
143 | case -ESHUTDOWN: |
144 | case -EILSEQ: |
145 | case -EPROTO: |
146 | case -ETIME: |
147 | return; |
148 | default: |
149 | dev_err(&dev->interface->dev, |
150 | "%s - unknown status received: %d\n" , __func__, status); |
151 | return; |
152 | } |
153 | |
154 | /* handle received message */ |
155 | switch (buf[0]) { |
156 | case CMD_COUNT: |
157 | case CMD_READ: |
158 | if (buf[6] == CMD_EOF) { |
159 | spin_lock_irqsave(&dev->lock, flags); |
160 | dev->bbu = 0; |
161 | for (i = 1; i < 6; i++) { |
162 | dev->bbu += buf[i]; |
163 | if (i != 5) |
164 | dev->bbu <<= 8; |
165 | } |
166 | dev_dbg(&dev->interface->dev, "%s count: %lld\n" , |
167 | __func__, dev->bbu); |
168 | spin_unlock_irqrestore(lock: &dev->lock, flags); |
169 | |
170 | kill_fasync(&dev->async_queue, SIGIO, POLL_IN); |
171 | } |
172 | else |
173 | dev_dbg(&dev->interface->dev, |
174 | "data format error - no EOF\n" ); |
175 | break; |
176 | case CMD_ACK: |
177 | dev_dbg(&dev->interface->dev, "%s ack: %c\n" , |
178 | __func__, buf[1]); |
179 | wake_up_interruptible(&dev->waitq); |
180 | break; |
181 | } |
182 | |
183 | retval = usb_submit_urb(urb: dev->urb, GFP_ATOMIC); |
184 | if (retval) { |
185 | dev_err(&dev->interface->dev, "%s - usb_submit_urb failed: %d\n" , |
186 | __func__, retval); |
187 | } |
188 | } |
189 | |
190 | static int yurex_probe(struct usb_interface *interface, const struct usb_device_id *id) |
191 | { |
192 | struct usb_yurex *dev; |
193 | struct usb_host_interface *iface_desc; |
194 | struct usb_endpoint_descriptor *endpoint; |
195 | int retval = -ENOMEM; |
196 | DEFINE_WAIT(wait); |
197 | int res; |
198 | |
199 | /* allocate memory for our device state and initialize it */ |
200 | dev = kzalloc(size: sizeof(*dev), GFP_KERNEL); |
201 | if (!dev) |
202 | goto error; |
203 | kref_init(kref: &dev->kref); |
204 | mutex_init(&dev->io_mutex); |
205 | spin_lock_init(&dev->lock); |
206 | init_waitqueue_head(&dev->waitq); |
207 | |
208 | dev->udev = usb_get_dev(interface_to_usbdev(interface)); |
209 | dev->interface = usb_get_intf(intf: interface); |
210 | |
211 | /* set up the endpoint information */ |
212 | iface_desc = interface->cur_altsetting; |
213 | res = usb_find_int_in_endpoint(alt: iface_desc, int_in: &endpoint); |
214 | if (res) { |
215 | dev_err(&interface->dev, "Could not find endpoints\n" ); |
216 | retval = res; |
217 | goto error; |
218 | } |
219 | |
220 | dev->int_in_endpointAddr = endpoint->bEndpointAddress; |
221 | |
222 | /* allocate control URB */ |
223 | dev->cntl_urb = usb_alloc_urb(iso_packets: 0, GFP_KERNEL); |
224 | if (!dev->cntl_urb) |
225 | goto error; |
226 | |
227 | /* allocate buffer for control req */ |
228 | dev->cntl_req = kmalloc(YUREX_BUF_SIZE, GFP_KERNEL); |
229 | if (!dev->cntl_req) |
230 | goto error; |
231 | |
232 | /* allocate buffer for control msg */ |
233 | dev->cntl_buffer = usb_alloc_coherent(dev: dev->udev, YUREX_BUF_SIZE, |
234 | GFP_KERNEL, |
235 | dma: &dev->cntl_urb->transfer_dma); |
236 | if (!dev->cntl_buffer) { |
237 | dev_err(&interface->dev, "Could not allocate cntl_buffer\n" ); |
238 | goto error; |
239 | } |
240 | |
241 | /* configure control URB */ |
242 | dev->cntl_req->bRequestType = USB_DIR_OUT | USB_TYPE_CLASS | |
243 | USB_RECIP_INTERFACE; |
244 | dev->cntl_req->bRequest = HID_REQ_SET_REPORT; |
245 | dev->cntl_req->wValue = cpu_to_le16((HID_OUTPUT_REPORT + 1) << 8); |
246 | dev->cntl_req->wIndex = cpu_to_le16(iface_desc->desc.bInterfaceNumber); |
247 | dev->cntl_req->wLength = cpu_to_le16(YUREX_BUF_SIZE); |
248 | |
249 | usb_fill_control_urb(urb: dev->cntl_urb, dev: dev->udev, |
250 | usb_sndctrlpipe(dev->udev, 0), |
251 | setup_packet: (void *)dev->cntl_req, transfer_buffer: dev->cntl_buffer, |
252 | YUREX_BUF_SIZE, complete_fn: yurex_control_callback, context: dev); |
253 | dev->cntl_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; |
254 | |
255 | |
256 | /* allocate interrupt URB */ |
257 | dev->urb = usb_alloc_urb(iso_packets: 0, GFP_KERNEL); |
258 | if (!dev->urb) |
259 | goto error; |
260 | |
261 | /* allocate buffer for interrupt in */ |
262 | dev->int_buffer = usb_alloc_coherent(dev: dev->udev, YUREX_BUF_SIZE, |
263 | GFP_KERNEL, dma: &dev->urb->transfer_dma); |
264 | if (!dev->int_buffer) { |
265 | dev_err(&interface->dev, "Could not allocate int_buffer\n" ); |
266 | goto error; |
267 | } |
268 | |
269 | /* configure interrupt URB */ |
270 | usb_fill_int_urb(urb: dev->urb, dev: dev->udev, |
271 | usb_rcvintpipe(dev->udev, dev->int_in_endpointAddr), |
272 | transfer_buffer: dev->int_buffer, YUREX_BUF_SIZE, complete_fn: yurex_interrupt, |
273 | context: dev, interval: 1); |
274 | dev->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; |
275 | if (usb_submit_urb(urb: dev->urb, GFP_KERNEL)) { |
276 | retval = -EIO; |
277 | dev_err(&interface->dev, "Could not submitting URB\n" ); |
278 | goto error; |
279 | } |
280 | |
281 | /* save our data pointer in this interface device */ |
282 | usb_set_intfdata(intf: interface, data: dev); |
283 | dev->bbu = -1; |
284 | |
285 | /* we can register the device now, as it is ready */ |
286 | retval = usb_register_dev(intf: interface, class_driver: &yurex_class); |
287 | if (retval) { |
288 | dev_err(&interface->dev, |
289 | "Not able to get a minor for this device.\n" ); |
290 | usb_set_intfdata(intf: interface, NULL); |
291 | goto error; |
292 | } |
293 | |
294 | dev_info(&interface->dev, |
295 | "USB YUREX device now attached to Yurex #%d\n" , |
296 | interface->minor); |
297 | |
298 | return 0; |
299 | |
300 | error: |
301 | if (dev) |
302 | /* this frees allocated memory */ |
303 | kref_put(kref: &dev->kref, release: yurex_delete); |
304 | return retval; |
305 | } |
306 | |
307 | static void yurex_disconnect(struct usb_interface *interface) |
308 | { |
309 | struct usb_yurex *dev; |
310 | int minor = interface->minor; |
311 | |
312 | dev = usb_get_intfdata(intf: interface); |
313 | usb_set_intfdata(intf: interface, NULL); |
314 | |
315 | /* give back our minor */ |
316 | usb_deregister_dev(intf: interface, class_driver: &yurex_class); |
317 | |
318 | /* prevent more I/O from starting */ |
319 | usb_poison_urb(urb: dev->urb); |
320 | usb_poison_urb(urb: dev->cntl_urb); |
321 | mutex_lock(&dev->io_mutex); |
322 | dev->disconnected = 1; |
323 | mutex_unlock(lock: &dev->io_mutex); |
324 | |
325 | /* wakeup waiters */ |
326 | kill_fasync(&dev->async_queue, SIGIO, POLL_IN); |
327 | wake_up_interruptible(&dev->waitq); |
328 | |
329 | /* decrement our usage count */ |
330 | kref_put(kref: &dev->kref, release: yurex_delete); |
331 | |
332 | dev_info(&interface->dev, "USB YUREX #%d now disconnected\n" , minor); |
333 | } |
334 | |
335 | static struct usb_driver yurex_driver = { |
336 | .name = "yurex" , |
337 | .probe = yurex_probe, |
338 | .disconnect = yurex_disconnect, |
339 | .id_table = yurex_table, |
340 | }; |
341 | |
342 | |
343 | static int yurex_fasync(int fd, struct file *file, int on) |
344 | { |
345 | struct usb_yurex *dev; |
346 | |
347 | dev = file->private_data; |
348 | return fasync_helper(fd, file, on, &dev->async_queue); |
349 | } |
350 | |
351 | static int yurex_open(struct inode *inode, struct file *file) |
352 | { |
353 | struct usb_yurex *dev; |
354 | struct usb_interface *interface; |
355 | int subminor; |
356 | int retval = 0; |
357 | |
358 | subminor = iminor(inode); |
359 | |
360 | interface = usb_find_interface(drv: &yurex_driver, minor: subminor); |
361 | if (!interface) { |
362 | printk(KERN_ERR "%s - error, can't find device for minor %d" , |
363 | __func__, subminor); |
364 | retval = -ENODEV; |
365 | goto exit; |
366 | } |
367 | |
368 | dev = usb_get_intfdata(intf: interface); |
369 | if (!dev) { |
370 | retval = -ENODEV; |
371 | goto exit; |
372 | } |
373 | |
374 | /* increment our usage count for the device */ |
375 | kref_get(kref: &dev->kref); |
376 | |
377 | /* save our object in the file's private structure */ |
378 | mutex_lock(&dev->io_mutex); |
379 | file->private_data = dev; |
380 | mutex_unlock(lock: &dev->io_mutex); |
381 | |
382 | exit: |
383 | return retval; |
384 | } |
385 | |
386 | static int yurex_release(struct inode *inode, struct file *file) |
387 | { |
388 | struct usb_yurex *dev; |
389 | |
390 | dev = file->private_data; |
391 | if (dev == NULL) |
392 | return -ENODEV; |
393 | |
394 | /* decrement the count on our device */ |
395 | kref_put(kref: &dev->kref, release: yurex_delete); |
396 | return 0; |
397 | } |
398 | |
399 | static ssize_t yurex_read(struct file *file, char __user *buffer, size_t count, |
400 | loff_t *ppos) |
401 | { |
402 | struct usb_yurex *dev; |
403 | int len = 0; |
404 | char in_buffer[20]; |
405 | unsigned long flags; |
406 | |
407 | dev = file->private_data; |
408 | |
409 | mutex_lock(&dev->io_mutex); |
410 | if (dev->disconnected) { /* already disconnected */ |
411 | mutex_unlock(lock: &dev->io_mutex); |
412 | return -ENODEV; |
413 | } |
414 | |
415 | spin_lock_irqsave(&dev->lock, flags); |
416 | len = snprintf(buf: in_buffer, size: 20, fmt: "%lld\n" , dev->bbu); |
417 | spin_unlock_irqrestore(lock: &dev->lock, flags); |
418 | mutex_unlock(lock: &dev->io_mutex); |
419 | |
420 | if (WARN_ON_ONCE(len >= sizeof(in_buffer))) |
421 | return -EIO; |
422 | |
423 | return simple_read_from_buffer(to: buffer, count, ppos, from: in_buffer, available: len); |
424 | } |
425 | |
426 | static ssize_t yurex_write(struct file *file, const char __user *user_buffer, |
427 | size_t count, loff_t *ppos) |
428 | { |
429 | struct usb_yurex *dev; |
430 | int i, set = 0, retval = 0; |
431 | char buffer[16 + 1]; |
432 | char *data = buffer; |
433 | unsigned long long c, c2 = 0; |
434 | signed long timeout = 0; |
435 | DEFINE_WAIT(wait); |
436 | |
437 | count = min(sizeof(buffer) - 1, count); |
438 | dev = file->private_data; |
439 | |
440 | /* verify that we actually have some data to write */ |
441 | if (count == 0) |
442 | goto error; |
443 | |
444 | mutex_lock(&dev->io_mutex); |
445 | if (dev->disconnected) { /* already disconnected */ |
446 | mutex_unlock(lock: &dev->io_mutex); |
447 | retval = -ENODEV; |
448 | goto error; |
449 | } |
450 | |
451 | if (copy_from_user(to: buffer, from: user_buffer, n: count)) { |
452 | mutex_unlock(lock: &dev->io_mutex); |
453 | retval = -EFAULT; |
454 | goto error; |
455 | } |
456 | buffer[count] = 0; |
457 | memset(dev->cntl_buffer, CMD_PADDING, YUREX_BUF_SIZE); |
458 | |
459 | switch (buffer[0]) { |
460 | case CMD_ANIMATE: |
461 | case CMD_LED: |
462 | dev->cntl_buffer[0] = buffer[0]; |
463 | dev->cntl_buffer[1] = buffer[1]; |
464 | dev->cntl_buffer[2] = CMD_EOF; |
465 | break; |
466 | case CMD_READ: |
467 | case CMD_VERSION: |
468 | dev->cntl_buffer[0] = buffer[0]; |
469 | dev->cntl_buffer[1] = 0x00; |
470 | dev->cntl_buffer[2] = CMD_EOF; |
471 | break; |
472 | case CMD_SET: |
473 | data++; |
474 | fallthrough; |
475 | case '0' ... '9': |
476 | set = 1; |
477 | c = c2 = simple_strtoull(data, NULL, 0); |
478 | dev->cntl_buffer[0] = CMD_SET; |
479 | for (i = 1; i < 6; i++) { |
480 | dev->cntl_buffer[i] = (c>>32) & 0xff; |
481 | c <<= 8; |
482 | } |
483 | buffer[6] = CMD_EOF; |
484 | break; |
485 | default: |
486 | mutex_unlock(lock: &dev->io_mutex); |
487 | return -EINVAL; |
488 | } |
489 | |
490 | /* send the data as the control msg */ |
491 | prepare_to_wait(wq_head: &dev->waitq, wq_entry: &wait, TASK_INTERRUPTIBLE); |
492 | dev_dbg(&dev->interface->dev, "%s - submit %c\n" , __func__, |
493 | dev->cntl_buffer[0]); |
494 | retval = usb_submit_urb(urb: dev->cntl_urb, GFP_ATOMIC); |
495 | if (retval >= 0) |
496 | timeout = schedule_timeout(YUREX_WRITE_TIMEOUT); |
497 | finish_wait(wq_head: &dev->waitq, wq_entry: &wait); |
498 | |
499 | /* make sure URB is idle after timeout or (spurious) CMD_ACK */ |
500 | usb_kill_urb(urb: dev->cntl_urb); |
501 | |
502 | mutex_unlock(lock: &dev->io_mutex); |
503 | |
504 | if (retval < 0) { |
505 | dev_err(&dev->interface->dev, |
506 | "%s - failed to send bulk msg, error %d\n" , |
507 | __func__, retval); |
508 | goto error; |
509 | } |
510 | if (set && timeout) |
511 | dev->bbu = c2; |
512 | return timeout ? count : -EIO; |
513 | |
514 | error: |
515 | return retval; |
516 | } |
517 | |
518 | static const struct file_operations yurex_fops = { |
519 | .owner = THIS_MODULE, |
520 | .read = yurex_read, |
521 | .write = yurex_write, |
522 | .open = yurex_open, |
523 | .release = yurex_release, |
524 | .fasync = yurex_fasync, |
525 | .llseek = default_llseek, |
526 | }; |
527 | |
528 | module_usb_driver(yurex_driver); |
529 | |
530 | MODULE_LICENSE("GPL" ); |
531 | |