yurex.c revision 65db43054065790a75291b0834657445fea2cf56 
1/*
2 * Driver for Meywa-Denki & KAYAC YUREX
3 *
4 * Copyright (C) 2010 Tomoki Sekiyama (tomoki.sekiyama@gmail.com)
5 *
6 *	This program is free software; you can redistribute it and/or
7 *	modify it under the terms of the GNU General Public License as
8 *	published by the Free Software Foundation, version 2.
9 *
10 */
11
12#include <linux/kernel.h>
13#include <linux/errno.h>
14#include <linux/init.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 */
43static struct usb_device_id yurex_table[] = {
44	{ USB_DEVICE(YUREX_VENDOR_ID, YUREX_PRODUCT_ID) },
45	{ }					/* Terminating entry */
46};
47MODULE_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 */
56struct 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
76static struct usb_driver yurex_driver;
77static const struct file_operations yurex_fops;
78
79
80static 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		err("%s - control failed: %d\n", __func__, status);
87		wake_up_interruptible(&dev->waitq);
88		return;
89	}
90	/* on success, sender woken up by CMD_ACK int in, or timeout */
91}
92
93static void yurex_delete(struct kref *kref)
94{
95	struct usb_yurex *dev = to_yurex_dev(kref);
96
97	dbg("yurex_delete");
98
99	usb_put_dev(dev->udev);
100	if (dev->cntl_urb) {
101		usb_kill_urb(dev->cntl_urb);
102		if (dev->cntl_req)
103			usb_free_coherent(dev->udev, YUREX_BUF_SIZE,
104				dev->cntl_req, dev->cntl_urb->setup_dma);
105		if (dev->cntl_buffer)
106			usb_free_coherent(dev->udev, YUREX_BUF_SIZE,
107				dev->cntl_buffer, dev->cntl_urb->transfer_dma);
108		usb_free_urb(dev->cntl_urb);
109	}
110	if (dev->urb) {
111		usb_kill_urb(dev->urb);
112		if (dev->int_buffer)
113			usb_free_coherent(dev->udev, YUREX_BUF_SIZE,
114				dev->int_buffer, dev->urb->transfer_dma);
115		usb_free_urb(dev->urb);
116	}
117	kfree(dev);
118}
119
120/*
121 * usb class driver info in order to get a minor number from the usb core,
122 * and to have the device registered with the driver core
123 */
124static struct usb_class_driver yurex_class = {
125	.name =		"yurex%d",
126	.fops =		&yurex_fops,
127	.minor_base =	YUREX_MINOR_BASE,
128};
129
130static void yurex_interrupt(struct urb *urb)
131{
132	struct usb_yurex *dev = urb->context;
133	unsigned char *buf = dev->int_buffer;
134	int status = urb->status;
135	unsigned long flags;
136	int retval, i;
137
138	switch (status) {
139	case 0: /*success*/
140		break;
141	case -EOVERFLOW:
142		err("%s - overflow with length %d, actual length is %d",
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		err("%s - unknown status received: %d", __func__, status);
152		goto exit;
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			dbg("%s count: %lld", __func__, dev->bbu);
168			spin_unlock_irqrestore(&dev->lock, flags);
169
170			kill_fasync(&dev->async_queue, SIGIO, POLL_IN);
171		}
172		else
173			dbg("data format error - no EOF");
174		break;
175	case CMD_ACK:
176		dbg("%s ack: %c", __func__, buf[1]);
177		wake_up_interruptible(&dev->waitq);
178		break;
179	}
180
181exit:
182	retval = usb_submit_urb(dev->urb, GFP_ATOMIC);
183	if (retval) {
184		err("%s - usb_submit_urb failed: %d",
185			__func__, retval);
186	}
187}
188
189static int yurex_probe(struct usb_interface *interface, const struct usb_device_id *id)
190{
191	struct usb_yurex *dev;
192	struct usb_host_interface *iface_desc;
193	struct usb_endpoint_descriptor *endpoint;
194	int retval = -ENOMEM;
195	int i;
196	DEFINE_WAIT(wait);
197
198	/* allocate memory for our device state and initialize it */
199	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
200	if (!dev) {
201		err("Out of memory");
202		goto error;
203	}
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 = interface;
211
212	/* set up the endpoint information */
213	iface_desc = interface->cur_altsetting;
214	for (i = 0; i < iface_desc->desc.bNumEndpoints; i++) {
215		endpoint = &iface_desc->endpoint[i].desc;
216
217		if (usb_endpoint_is_int_in(endpoint)) {
218			dev->int_in_endpointAddr = endpoint->bEndpointAddress;
219			break;
220		}
221	}
222	if (!dev->int_in_endpointAddr) {
223		retval = -ENODEV;
224		err("Could not find endpoints");
225		goto error;
226	}
227
228
229	/* allocate control URB */
230	dev->cntl_urb = usb_alloc_urb(0, GFP_KERNEL);
231	if (!dev->cntl_urb) {
232		err("Could not allocate control URB");
233		goto error;
234	}
235
236	/* allocate buffer for control req */
237	dev->cntl_req = usb_alloc_coherent(dev->udev, YUREX_BUF_SIZE,
238					   GFP_KERNEL,
239					   &dev->cntl_urb->setup_dma);
240	if (!dev->cntl_req) {
241		err("Could not allocate cntl_req");
242		goto error;
243	}
244
245	/* allocate buffer for control msg */
246	dev->cntl_buffer = usb_alloc_coherent(dev->udev, YUREX_BUF_SIZE,
247					      GFP_KERNEL,
248					      &dev->cntl_urb->transfer_dma);
249	if (!dev->cntl_buffer) {
250		err("Could not allocate cntl_buffer");
251		goto error;
252	}
253
254	/* configure control URB */
255	dev->cntl_req->bRequestType = USB_DIR_OUT | USB_TYPE_CLASS |
256				      USB_RECIP_INTERFACE;
257	dev->cntl_req->bRequest	= HID_REQ_SET_REPORT;
258	dev->cntl_req->wValue	= cpu_to_le16((HID_OUTPUT_REPORT + 1) << 8);
259	dev->cntl_req->wIndex	= cpu_to_le16(iface_desc->desc.bInterfaceNumber);
260	dev->cntl_req->wLength	= cpu_to_le16(YUREX_BUF_SIZE);
261
262	usb_fill_control_urb(dev->cntl_urb, dev->udev,
263			     usb_sndctrlpipe(dev->udev, 0),
264			     (void *)dev->cntl_req, dev->cntl_buffer,
265			     YUREX_BUF_SIZE, yurex_control_callback, dev);
266	dev->cntl_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
267
268
269	/* allocate interrupt URB */
270	dev->urb = usb_alloc_urb(0, GFP_KERNEL);
271	if (!dev->urb) {
272		err("Could not allocate URB");
273		goto error;
274	}
275
276	/* allocate buffer for interrupt in */
277	dev->int_buffer = usb_alloc_coherent(dev->udev, YUREX_BUF_SIZE,
278					GFP_KERNEL, &dev->urb->transfer_dma);
279	if (!dev->int_buffer) {
280		err("Could not allocate int_buffer");
281		goto error;
282	}
283
284	/* configure interrupt URB */
285	usb_fill_int_urb(dev->urb, dev->udev,
286			 usb_rcvintpipe(dev->udev, dev->int_in_endpointAddr),
287			 dev->int_buffer, YUREX_BUF_SIZE, yurex_interrupt,
288			 dev, 1);
289	dev->cntl_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
290	if (usb_submit_urb(dev->urb, GFP_KERNEL)) {
291		retval = -EIO;
292		err("Could not submitting URB");
293		goto error;
294	}
295
296	/* save our data pointer in this interface device */
297	usb_set_intfdata(interface, dev);
298
299	/* we can register the device now, as it is ready */
300	retval = usb_register_dev(interface, &yurex_class);
301	if (retval) {
302		err("Not able to get a minor for this device.");
303		usb_set_intfdata(interface, NULL);
304		goto error;
305	}
306
307	dev->bbu = -1;
308
309	dev_info(&interface->dev,
310		 "USB YUREX device now attached to Yurex #%d\n",
311		 interface->minor);
312
313	return 0;
314
315error:
316	if (dev)
317		/* this frees allocated memory */
318		kref_put(&dev->kref, yurex_delete);
319	return retval;
320}
321
322static void yurex_disconnect(struct usb_interface *interface)
323{
324	struct usb_yurex *dev;
325	int minor = interface->minor;
326
327	dev = usb_get_intfdata(interface);
328	usb_set_intfdata(interface, NULL);
329
330	/* give back our minor */
331	usb_deregister_dev(interface, &yurex_class);
332
333	/* prevent more I/O from starting */
334	mutex_lock(&dev->io_mutex);
335	dev->interface = NULL;
336	mutex_unlock(&dev->io_mutex);
337
338	/* wakeup waiters */
339	kill_fasync(&dev->async_queue, SIGIO, POLL_IN);
340	wake_up_interruptible(&dev->waitq);
341
342	/* decrement our usage count */
343	kref_put(&dev->kref, yurex_delete);
344
345	dev_info(&interface->dev, "USB YUREX #%d now disconnected\n", minor);
346}
347
348static struct usb_driver yurex_driver = {
349	.name =		"yurex",
350	.probe =	yurex_probe,
351	.disconnect =	yurex_disconnect,
352	.id_table =	yurex_table,
353};
354
355
356static int yurex_fasync(int fd, struct file *file, int on)
357{
358	struct usb_yurex *dev;
359
360	dev = (struct usb_yurex *)file->private_data;
361	return fasync_helper(fd, file, on, &dev->async_queue);
362}
363
364static int yurex_open(struct inode *inode, struct file *file)
365{
366	struct usb_yurex *dev;
367	struct usb_interface *interface;
368	int subminor;
369	int retval = 0;
370
371	subminor = iminor(inode);
372
373	interface = usb_find_interface(&yurex_driver, subminor);
374	if (!interface) {
375		err("%s - error, can't find device for minor %d",
376		    __func__, subminor);
377		retval = -ENODEV;
378		goto exit;
379	}
380
381	dev = usb_get_intfdata(interface);
382	if (!dev) {
383		retval = -ENODEV;
384		goto exit;
385	}
386
387	/* increment our usage count for the device */
388	kref_get(&dev->kref);
389
390	/* save our object in the file's private structure */
391	mutex_lock(&dev->io_mutex);
392	file->private_data = dev;
393	mutex_unlock(&dev->io_mutex);
394
395exit:
396	return retval;
397}
398
399static int yurex_release(struct inode *inode, struct file *file)
400{
401	struct usb_yurex *dev;
402
403	dev = (struct usb_yurex *)file->private_data;
404	if (dev == NULL)
405		return -ENODEV;
406
407	yurex_fasync(-1, file, 0);
408
409	/* decrement the count on our device */
410	kref_put(&dev->kref, yurex_delete);
411	return 0;
412}
413
414static ssize_t yurex_read(struct file *file, char *buffer, size_t count, loff_t *ppos)
415{
416	struct usb_yurex *dev;
417	int retval = 0;
418	int bytes_read = 0;
419	char in_buffer[20];
420	unsigned long flags;
421
422	dev = (struct usb_yurex *)file->private_data;
423
424	mutex_lock(&dev->io_mutex);
425	if (!dev->interface) {		/* already disconnected */
426		retval = -ENODEV;
427		goto exit;
428	}
429
430	spin_lock_irqsave(&dev->lock, flags);
431	bytes_read = snprintf(in_buffer, 20, "%lld\n", dev->bbu);
432	spin_unlock_irqrestore(&dev->lock, flags);
433
434	if (*ppos < bytes_read) {
435		if (copy_to_user(buffer, in_buffer + *ppos, bytes_read - *ppos))
436			retval = -EFAULT;
437		else {
438			retval = bytes_read - *ppos;
439			*ppos += bytes_read;
440		}
441	}
442
443exit:
444	mutex_unlock(&dev->io_mutex);
445	return retval;
446}
447
448static ssize_t yurex_write(struct file *file, const char *user_buffer, size_t count, loff_t *ppos)
449{
450	struct usb_yurex *dev;
451	int i, set = 0, retval = 0;
452	char buffer[16];
453	char *data = buffer;
454	unsigned long long c, c2 = 0;
455	signed long timeout = 0;
456	DEFINE_WAIT(wait);
457
458	count = min(sizeof(buffer), count);
459	dev = (struct usb_yurex *)file->private_data;
460
461	/* verify that we actually have some data to write */
462	if (count == 0)
463		goto error;
464
465	mutex_lock(&dev->io_mutex);
466	if (!dev->interface) {		/* alreaday disconnected */
467		mutex_unlock(&dev->io_mutex);
468		retval = -ENODEV;
469		goto error;
470	}
471
472	if (copy_from_user(buffer, user_buffer, count)) {
473		mutex_unlock(&dev->io_mutex);
474		retval = -EFAULT;
475		goto error;
476	}
477	memset(dev->cntl_buffer, CMD_PADDING, YUREX_BUF_SIZE);
478
479	switch (buffer[0]) {
480	case CMD_ANIMATE:
481	case CMD_LED:
482		dev->cntl_buffer[0] = buffer[0];
483		dev->cntl_buffer[1] = buffer[1];
484		dev->cntl_buffer[2] = CMD_EOF;
485		break;
486	case CMD_READ:
487	case CMD_VERSION:
488		dev->cntl_buffer[0] = buffer[0];
489		dev->cntl_buffer[1] = 0x00;
490		dev->cntl_buffer[2] = CMD_EOF;
491		break;
492	case CMD_SET:
493		data++;
494		/* FALL THROUGH */
495	case '0' ... '9':
496		set = 1;
497		c = c2 = simple_strtoull(data, NULL, 0);
498		dev->cntl_buffer[0] = CMD_SET;
499		for (i = 1; i < 6; i++) {
500			dev->cntl_buffer[i] = (c>>32) & 0xff;
501			c <<= 8;
502		}
503		buffer[6] = CMD_EOF;
504		break;
505	default:
506		mutex_unlock(&dev->io_mutex);
507		return -EINVAL;
508	}
509
510	/* send the data as the control msg */
511	prepare_to_wait(&dev->waitq, &wait, TASK_INTERRUPTIBLE);
512	dbg("%s - submit %c", __func__, dev->cntl_buffer[0]);
513	retval = usb_submit_urb(dev->cntl_urb, GFP_KERNEL);
514	if (retval >= 0)
515		timeout = schedule_timeout(YUREX_WRITE_TIMEOUT);
516	finish_wait(&dev->waitq, &wait);
517
518	mutex_unlock(&dev->io_mutex);
519
520	if (retval < 0) {
521		err("%s - failed to send bulk msg, error %d", __func__, retval);
522		goto error;
523	}
524	if (set && timeout)
525		dev->bbu = c2;
526	return timeout ? count : -EIO;
527
528error:
529	return retval;
530}
531
532static const struct file_operations yurex_fops = {
533	.owner =	THIS_MODULE,
534	.read =		yurex_read,
535	.write =	yurex_write,
536	.open =		yurex_open,
537	.release =	yurex_release,
538	.fasync	=	yurex_fasync,
539	.llseek =	default_llseek,
540};
541
542module_usb_driver(yurex_driver);
543
544MODULE_LICENSE("GPL");
545