1	// SPDX-License-Identifier: GPL-2.0-or-later
2	/* ZD1211 USB-WLAN driver for Linux
3	*
4	* Copyright (C) 2005-2007 Ulrich Kunitz <kune@deine-taler.de>
5	* Copyright (C) 2006-2007 Daniel Drake <dsd@gentoo.org>
6	* Copyright (C) 2006-2007 Michael Wu <flamingice@sourmilk.net>
7	*/
8
9	#include <linux/kernel.h>
10	#include <linux/init.h>
11	#include <linux/firmware.h>
12	#include <linux/device.h>
13	#include <linux/errno.h>
14	#include <linux/slab.h>
15	#include <linux/skbuff.h>
16	#include <linux/usb.h>
17	#include <linux/workqueue.h>
18	#include <linux/module.h>
19	#include <net/mac80211.h>
20	#include <asm/unaligned.h>
21
22	#include "zd_def.h"
23	#include "zd_mac.h"
24	#include "zd_usb.h"
25
26	static const struct usb_device_id usb_ids[] = {
27	/* ZD1211 */
28	{ USB_DEVICE(0x0105, 0x145f), .driver_info = DEVICE_ZD1211 },
29	{ USB_DEVICE(0x0586, 0x3401), .driver_info = DEVICE_ZD1211 },
30	{ USB_DEVICE(0x0586, 0x3402), .driver_info = DEVICE_ZD1211 },
31	{ USB_DEVICE(0x0586, 0x3407), .driver_info = DEVICE_ZD1211 },
32	{ USB_DEVICE(0x0586, 0x3409), .driver_info = DEVICE_ZD1211 },
33	{ USB_DEVICE(0x079b, 0x004a), .driver_info = DEVICE_ZD1211 },
34	{ USB_DEVICE(0x07b8, 0x6001), .driver_info = DEVICE_ZD1211 },
35	{ USB_DEVICE(0x0ace, 0x1211), .driver_info = DEVICE_ZD1211 },
36	{ USB_DEVICE(0x0ace, 0xa211), .driver_info = DEVICE_ZD1211 },
37	{ USB_DEVICE(0x0b05, 0x170c), .driver_info = DEVICE_ZD1211 },
38	{ USB_DEVICE(0x0b3b, 0x1630), .driver_info = DEVICE_ZD1211 },
39	{ USB_DEVICE(0x0b3b, 0x5630), .driver_info = DEVICE_ZD1211 },
40	{ USB_DEVICE(0x0df6, 0x9071), .driver_info = DEVICE_ZD1211 },
41	{ USB_DEVICE(0x0df6, 0x9075), .driver_info = DEVICE_ZD1211 },
42	{ USB_DEVICE(0x126f, 0xa006), .driver_info = DEVICE_ZD1211 },
43	{ USB_DEVICE(0x129b, 0x1666), .driver_info = DEVICE_ZD1211 },
44	{ USB_DEVICE(0x13b1, 0x001e), .driver_info = DEVICE_ZD1211 },
45	{ USB_DEVICE(0x1435, 0x0711), .driver_info = DEVICE_ZD1211 },
46	{ USB_DEVICE(0x14ea, 0xab10), .driver_info = DEVICE_ZD1211 },
47	{ USB_DEVICE(0x14ea, 0xab13), .driver_info = DEVICE_ZD1211 },
48	{ USB_DEVICE(0x157e, 0x300a), .driver_info = DEVICE_ZD1211 },
49	{ USB_DEVICE(0x157e, 0x300b), .driver_info = DEVICE_ZD1211 },
50	{ USB_DEVICE(0x157e, 0x3204), .driver_info = DEVICE_ZD1211 },
51	{ USB_DEVICE(0x157e, 0x3207), .driver_info = DEVICE_ZD1211 },
52	{ USB_DEVICE(0x1740, 0x2000), .driver_info = DEVICE_ZD1211 },
53	{ USB_DEVICE(0x6891, 0xa727), .driver_info = DEVICE_ZD1211 },
54	/* ZD1211B */
55	{ USB_DEVICE(0x0053, 0x5301), .driver_info = DEVICE_ZD1211B },
56	{ USB_DEVICE(0x0409, 0x0248), .driver_info = DEVICE_ZD1211B },
57	{ USB_DEVICE(0x0411, 0x00da), .driver_info = DEVICE_ZD1211B },
58	{ USB_DEVICE(0x0471, 0x1236), .driver_info = DEVICE_ZD1211B },
59	{ USB_DEVICE(0x0471, 0x1237), .driver_info = DEVICE_ZD1211B },
60	{ USB_DEVICE(0x050d, 0x705c), .driver_info = DEVICE_ZD1211B },
61	{ USB_DEVICE(0x054c, 0x0257), .driver_info = DEVICE_ZD1211B },
62	{ USB_DEVICE(0x0586, 0x340a), .driver_info = DEVICE_ZD1211B },
63	{ USB_DEVICE(0x0586, 0x340f), .driver_info = DEVICE_ZD1211B },
64	{ USB_DEVICE(0x0586, 0x3410), .driver_info = DEVICE_ZD1211B },
65	{ USB_DEVICE(0x0586, 0x3412), .driver_info = DEVICE_ZD1211B },
66	{ USB_DEVICE(0x0586, 0x3413), .driver_info = DEVICE_ZD1211B },
67	{ USB_DEVICE(0x079b, 0x0062), .driver_info = DEVICE_ZD1211B },
68	{ USB_DEVICE(0x07fa, 0x1196), .driver_info = DEVICE_ZD1211B },
69	{ USB_DEVICE(0x083a, 0x4505), .driver_info = DEVICE_ZD1211B },
70	{ USB_DEVICE(0x083a, 0xe501), .driver_info = DEVICE_ZD1211B },
71	{ USB_DEVICE(0x083a, 0xe503), .driver_info = DEVICE_ZD1211B },
72	{ USB_DEVICE(0x083a, 0xe506), .driver_info = DEVICE_ZD1211B },
73	{ USB_DEVICE(0x0ace, 0x1215), .driver_info = DEVICE_ZD1211B },
74	{ USB_DEVICE(0x0ace, 0xb215), .driver_info = DEVICE_ZD1211B },
75	{ USB_DEVICE(0x0b05, 0x171b), .driver_info = DEVICE_ZD1211B },
76	{ USB_DEVICE(0x0baf, 0x0121), .driver_info = DEVICE_ZD1211B },
77	{ USB_DEVICE(0x0cde, 0x001a), .driver_info = DEVICE_ZD1211B },
78	{ USB_DEVICE(0x0df6, 0x0036), .driver_info = DEVICE_ZD1211B },
79	{ USB_DEVICE(0x129b, 0x1667), .driver_info = DEVICE_ZD1211B },
80	{ USB_DEVICE(0x13b1, 0x0024), .driver_info = DEVICE_ZD1211B },
81	{ USB_DEVICE(0x157e, 0x300d), .driver_info = DEVICE_ZD1211B },
82	{ USB_DEVICE(0x1582, 0x6003), .driver_info = DEVICE_ZD1211B },
83	{ USB_DEVICE(0x2019, 0x5303), .driver_info = DEVICE_ZD1211B },
84	{ USB_DEVICE(0x2019, 0xed01), .driver_info = DEVICE_ZD1211B },
85	/* "Driverless" devices that need ejecting */
86	{ USB_DEVICE(0x0ace, 0x2011), .driver_info = DEVICE_INSTALLER },
87	{ USB_DEVICE(0x0ace, 0x20ff), .driver_info = DEVICE_INSTALLER },
88	{}
89	};
90
91	MODULE_LICENSE("GPL");
92	MODULE_DESCRIPTION("USB driver for devices with the ZD1211 chip.");
93	MODULE_AUTHOR("Ulrich Kunitz");
94	MODULE_AUTHOR("Daniel Drake");
95	MODULE_VERSION("1.0");
96	MODULE_DEVICE_TABLE(usb, usb_ids);
97
98	#define FW_ZD1211_PREFIX "zd1211/zd1211_"
99	#define FW_ZD1211B_PREFIX "zd1211/zd1211b_"
100
101	static bool check_read_regs(struct zd_usb *usb, struct usb_req_read_regs *req,
102	unsigned int count);
103
104	/* USB device initialization */
105	static void int_urb_complete(struct urb *urb);
106
107	static int request_fw_file(
108	const struct firmware **fw, const char *name, struct device *device)
109	{
110	int r;
111
112	dev_dbg_f(device, "fw name %s\n", name);
113
114	r = request_firmware(fw, name, device);
115	if (r)
116	dev_err(device,
117	"Could not load firmware file %s. Error number %d\n",
118	name, r);
119	return r;
120	}
121
122	static inline u16 get_bcdDevice(const struct usb_device *udev)
123	{
124	return le16_to_cpu(udev->descriptor.bcdDevice);
125	}
126
127	enum upload_code_flags {
128	REBOOT = 1,
129	};
130
131	/* Ensures that MAX_TRANSFER_SIZE is even. */
132	#define MAX_TRANSFER_SIZE (USB_MAX_TRANSFER_SIZE & ~1)
133
134	static int upload_code(struct usb_device *udev,
135	const u8 *data, size_t size, u16 code_offset, int flags)
136	{
137	u8 *p;
138	int r;
139
140	/* USB request blocks need "kmalloced" buffers.
141	*/
142	p = kmalloc(MAX_TRANSFER_SIZE, GFP_KERNEL);
143	if (!p) {
144	r = -ENOMEM;
145	goto error;
146	}
147
148	size &= ~1;
149	while (size > 0) {
150	size_t transfer_size = size <= MAX_TRANSFER_SIZE ?
151	size : MAX_TRANSFER_SIZE;
152
153	dev_dbg_f(&udev->dev, "transfer size %zu\n", transfer_size);
154
155	memcpy(p, data, transfer_size);
156	r = usb_control_msg(dev: udev, usb_sndctrlpipe(udev, 0),
157	request: USB_REQ_FIRMWARE_DOWNLOAD,
158	USB_DIR_OUT | USB_TYPE_VENDOR,
159	value: code_offset, index: 0, data: p, size: transfer_size, timeout: 1000 /* ms */);
160	if (r < 0) {
161	dev_err(&udev->dev,
162	"USB control request for firmware upload"
163	" failed. Error number %d\n", r);
164	goto error;
165	}
166	transfer_size = r & ~1;
167
168	size -= transfer_size;
169	data += transfer_size;
170	code_offset += transfer_size/sizeof(u16);
171	}
172
173	if (flags & REBOOT) {
174	u8 ret;
175
176	/* Use "DMA-aware" buffer. */
177	r = usb_control_msg(dev: udev, usb_rcvctrlpipe(udev, 0),
178	request: USB_REQ_FIRMWARE_CONFIRM,
179	USB_DIR_IN | USB_TYPE_VENDOR,
180	value: 0, index: 0, data: p, size: sizeof(ret), timeout: 5000 /* ms */);
181	if (r != sizeof(ret)) {
182	dev_err(&udev->dev,
183	"control request firmware confirmation failed."
184	" Return value %d\n", r);
185	if (r >= 0)
186	r = -ENODEV;
187	goto error;
188	}
189	ret = p[0];
190	if (ret & 0x80) {
191	dev_err(&udev->dev,
192	"Internal error while downloading."
193	" Firmware confirm return value %#04x\n",
194	(unsigned int)ret);
195	r = -ENODEV;
196	goto error;
197	}
198	dev_dbg_f(&udev->dev, "firmware confirm return value %#04x\n",
199	(unsigned int)ret);
200	}
201
202	r = 0;
203	error:
204	kfree(objp: p);
205	return r;
206	}
207
208	static u16 get_word(const void *data, u16 offset)
209	{
210	const __le16 *p = data;
211	return le16_to_cpu(p[offset]);
212	}
213
214	static char *get_fw_name(struct zd_usb *usb, char *buffer, size_t size,
215	const char* postfix)
216	{
217	scnprintf(buf: buffer, size, fmt: "%s%s",
218	usb->is_zd1211b ?
219	FW_ZD1211B_PREFIX : FW_ZD1211_PREFIX,
220	postfix);
221	return buffer;
222	}
223
224	static int handle_version_mismatch(struct zd_usb *usb,
225	const struct firmware *ub_fw)
226	{
227	struct usb_device *udev = zd_usb_to_usbdev(usb);
228	const struct firmware *ur_fw = NULL;
229	int offset;
230	int r = 0;
231	char fw_name[128];
232
233	r = request_fw_file(fw: &ur_fw,
234	name: get_fw_name(usb, buffer: fw_name, size: sizeof(fw_name), postfix: "ur"),
235	device: &udev->dev);
236	if (r)
237	goto error;
238
239	r = upload_code(udev, data: ur_fw->data, size: ur_fw->size, code_offset: FW_START, flags: REBOOT);
240	if (r)
241	goto error;
242
243	offset = (E2P_BOOT_CODE_OFFSET * sizeof(u16));
244	r = upload_code(udev, data: ub_fw->data + offset, size: ub_fw->size - offset,
245	code_offset: E2P_START + E2P_BOOT_CODE_OFFSET, flags: REBOOT);
246
247	/* At this point, the vendor driver downloads the whole firmware
248	* image, hacks around with version IDs, and uploads it again,
249	* completely overwriting the boot code. We do not do this here as
250	* it is not required on any tested devices, and it is suspected to
251	* cause problems. */
252	error:
253	release_firmware(fw: ur_fw);
254	return r;
255	}
256
257	static int upload_firmware(struct zd_usb *usb)
258	{
259	int r;
260	u16 fw_bcdDevice;
261	u16 bcdDevice;
262	struct usb_device *udev = zd_usb_to_usbdev(usb);
263	const struct firmware *ub_fw = NULL;
264	const struct firmware *uph_fw = NULL;
265	char fw_name[128];
266
267	bcdDevice = get_bcdDevice(udev);
268
269	r = request_fw_file(fw: &ub_fw,
270	name: get_fw_name(usb, buffer: fw_name, size: sizeof(fw_name), postfix: "ub"),
271	device: &udev->dev);
272	if (r)
273	goto error;
274
275	fw_bcdDevice = get_word(data: ub_fw->data, offset: E2P_DATA_OFFSET);
276
277	if (fw_bcdDevice != bcdDevice) {
278	dev_info(&udev->dev,
279	"firmware version %#06x and device bootcode version "
280	"%#06x differ\n", fw_bcdDevice, bcdDevice);
281	if (bcdDevice <= 0x4313)
282	dev_warn(&udev->dev, "device has old bootcode, please "
283	"report success or failure\n");
284
285	r = handle_version_mismatch(usb, ub_fw);
286	if (r)
287	goto error;
288	} else {
289	dev_dbg_f(&udev->dev,
290	"firmware device id %#06x is equal to the "
291	"actual device id\n", fw_bcdDevice);
292	}
293
294
295	r = request_fw_file(fw: &uph_fw,
296	name: get_fw_name(usb, buffer: fw_name, size: sizeof(fw_name), postfix: "uphr"),
297	device: &udev->dev);
298	if (r)
299	goto error;
300
301	r = upload_code(udev, data: uph_fw->data, size: uph_fw->size, code_offset: FW_START, flags: REBOOT);
302	if (r) {
303	dev_err(&udev->dev,
304	"Could not upload firmware code uph. Error number %d\n",
305	r);
306	}
307
308	/* FALL-THROUGH */
309	error:
310	release_firmware(fw: ub_fw);
311	release_firmware(fw: uph_fw);
312	return r;
313	}
314
315	MODULE_FIRMWARE(FW_ZD1211B_PREFIX "ur");
316	MODULE_FIRMWARE(FW_ZD1211_PREFIX "ur");
317	MODULE_FIRMWARE(FW_ZD1211B_PREFIX "ub");
318	MODULE_FIRMWARE(FW_ZD1211_PREFIX "ub");
319	MODULE_FIRMWARE(FW_ZD1211B_PREFIX "uphr");
320	MODULE_FIRMWARE(FW_ZD1211_PREFIX "uphr");
321
322	/* Read data from device address space using "firmware interface" which does
323	* not require firmware to be loaded. */
324	int zd_usb_read_fw(struct zd_usb *usb, zd_addr_t addr, u8 *data, u16 len)
325	{
326	int r;
327	struct usb_device *udev = zd_usb_to_usbdev(usb);
328	u8 *buf;
329
330	/* Use "DMA-aware" buffer. */
331	buf = kmalloc(size: len, GFP_KERNEL);
332	if (!buf)
333	return -ENOMEM;
334	r = usb_control_msg(dev: udev, usb_rcvctrlpipe(udev, 0),
335	request: USB_REQ_FIRMWARE_READ_DATA, USB_DIR_IN | 0x40, value: addr, index: 0,
336	data: buf, size: len, timeout: 5000);
337	if (r < 0) {
338	dev_err(&udev->dev,
339	"read over firmware interface failed: %d\n", r);
340	goto exit;
341	} else if (r != len) {
342	dev_err(&udev->dev,
343	"incomplete read over firmware interface: %d/%d\n",
344	r, len);
345	r = -EIO;
346	goto exit;
347	}
348	r = 0;
349	memcpy(data, buf, len);
350	exit:
351	kfree(objp: buf);
352	return r;
353	}
354
355	#define urb_dev(urb) (&(urb)->dev->dev)
356
357	static inline void handle_regs_int_override(struct urb *urb)
358	{
359	struct zd_usb *usb = urb->context;
360	struct zd_usb_interrupt *intr = &usb->intr;
361	unsigned long flags;
362
363	spin_lock_irqsave(&intr->lock, flags);
364	if (atomic_read(v: &intr->read_regs_enabled)) {
365	atomic_set(v: &intr->read_regs_enabled, i: 0);
366	intr->read_regs_int_overridden = 1;
367	complete(&intr->read_regs.completion);
368	}
369	spin_unlock_irqrestore(lock: &intr->lock, flags);
370	}
371
372	static inline void handle_regs_int(struct urb *urb)
373	{
374	struct zd_usb *usb = urb->context;
375	struct zd_usb_interrupt *intr = &usb->intr;
376	unsigned long flags;
377	int len;
378	u16 int_num;
379
380	spin_lock_irqsave(&intr->lock, flags);
381
382	int_num = le16_to_cpu(*(__le16 *)(urb->transfer_buffer+2));
383	if (int_num == (u16)CR_INTERRUPT) {
384	struct zd_mac *mac = zd_hw_mac(hw: zd_usb_to_hw(usb: urb->context));
385	spin_lock(lock: &mac->lock);
386	memcpy(&mac->intr_buffer, urb->transfer_buffer,
387	USB_MAX_EP_INT_BUFFER);
388	spin_unlock(lock: &mac->lock);
389	schedule_work(work: &mac->process_intr);
390	} else if (atomic_read(v: &intr->read_regs_enabled)) {
391	len = urb->actual_length;
392	intr->read_regs.length = urb->actual_length;
393	if (len > sizeof(intr->read_regs.buffer))
394	len = sizeof(intr->read_regs.buffer);
395
396	memcpy(intr->read_regs.buffer, urb->transfer_buffer, len);
397
398	/* Sometimes USB_INT_ID_REGS is not overridden, but comes after
399	* USB_INT_ID_RETRY_FAILED. Read-reg retry then gets this
400	* delayed USB_INT_ID_REGS, but leaves USB_INT_ID_REGS of
401	* retry unhandled. Next read-reg command then might catch
402	* this wrong USB_INT_ID_REGS. Fix by ignoring wrong reads.
403	*/
404	if (!check_read_regs(usb, req: intr->read_regs.req,
405	count: intr->read_regs.req_count))
406	goto out;
407
408	atomic_set(v: &intr->read_regs_enabled, i: 0);
409	intr->read_regs_int_overridden = 0;
410	complete(&intr->read_regs.completion);
411
412	goto out;
413	}
414
415	out:
416	spin_unlock_irqrestore(lock: &intr->lock, flags);
417
418	/* CR_INTERRUPT might override read_reg too. */
419	if (int_num == (u16)CR_INTERRUPT &&
420	atomic_read(v: &intr->read_regs_enabled))
421	handle_regs_int_override(urb);
422	}
423
424	static void int_urb_complete(struct urb *urb)
425	{
426	int r;
427	struct usb_int_header *hdr;
428	struct zd_usb *usb;
429	struct zd_usb_interrupt *intr;
430
431	switch (urb->status) {
432	case 0:
433	break;
434	case -ESHUTDOWN:
435	case -EINVAL:
436	case -ENODEV:
437	case -ENOENT:
438	case -ECONNRESET:
439	case -EPIPE:
440	dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
441	return;
442	default:
443	dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
444	goto resubmit;
445	}
446
447	if (urb->actual_length < sizeof(hdr)) {
448	dev_dbg_f(urb_dev(urb), "error: urb %p to small\n", urb);
449	goto resubmit;
450	}
451
452	hdr = urb->transfer_buffer;
453	if (hdr->type != USB_INT_TYPE) {
454	dev_dbg_f(urb_dev(urb), "error: urb %p wrong type\n", urb);
455	goto resubmit;
456	}
457
458	/* USB_INT_ID_RETRY_FAILED triggered by tx-urb submit can override
459	* pending USB_INT_ID_REGS causing read command timeout.
460	*/
461	usb = urb->context;
462	intr = &usb->intr;
463	if (hdr->id != USB_INT_ID_REGS && atomic_read(v: &intr->read_regs_enabled))
464	handle_regs_int_override(urb);
465
466	switch (hdr->id) {
467	case USB_INT_ID_REGS:
468	handle_regs_int(urb);
469	break;
470	case USB_INT_ID_RETRY_FAILED:
471	zd_mac_tx_failed(urb);
472	break;
473	default:
474	dev_dbg_f(urb_dev(urb), "error: urb %p unknown id %x\n", urb,
475	(unsigned int)hdr->id);
476	goto resubmit;
477	}
478
479	resubmit:
480	r = usb_submit_urb(urb, GFP_ATOMIC);
481	if (r) {
482	dev_dbg_f(urb_dev(urb), "error: resubmit urb %p err code %d\n",
483	urb, r);
484	/* TODO: add worker to reset intr->urb */
485	}
486	return;
487	}
488
489	static inline int int_urb_interval(struct usb_device *udev)
490	{
491	switch (udev->speed) {
492	case USB_SPEED_HIGH:
493	return 4;
494	case USB_SPEED_LOW:
495	return 10;
496	case USB_SPEED_FULL:
497	default:
498	return 1;
499	}
500	}
501
502	static inline int usb_int_enabled(struct zd_usb *usb)
503	{
504	unsigned long flags;
505	struct zd_usb_interrupt *intr = &usb->intr;
506	struct urb *urb;
507
508	spin_lock_irqsave(&intr->lock, flags);
509	urb = intr->urb;
510	spin_unlock_irqrestore(lock: &intr->lock, flags);
511	return urb != NULL;
512	}
513
514	int zd_usb_enable_int(struct zd_usb *usb)
515	{
516	int r;
517	struct usb_device *udev = zd_usb_to_usbdev(usb);
518	struct zd_usb_interrupt *intr = &usb->intr;
519	struct urb *urb;
520
521	dev_dbg_f(zd_usb_dev(usb), "\n");
522
523	urb = usb_alloc_urb(iso_packets: 0, GFP_KERNEL);
524	if (!urb) {
525	r = -ENOMEM;
526	goto out;
527	}
528
529	ZD_ASSERT(!irqs_disabled());
530	spin_lock_irq(lock: &intr->lock);
531	if (intr->urb) {
532	spin_unlock_irq(lock: &intr->lock);
533	r = 0;
534	goto error_free_urb;
535	}
536	intr->urb = urb;
537	spin_unlock_irq(lock: &intr->lock);
538
539	r = -ENOMEM;
540	intr->buffer = usb_alloc_coherent(dev: udev, size: USB_MAX_EP_INT_BUFFER,
541	GFP_KERNEL, dma: &intr->buffer_dma);
542	if (!intr->buffer) {
543	dev_dbg_f(zd_usb_dev(usb),
544	"couldn't allocate transfer_buffer\n");
545	goto error_set_urb_null;
546	}
547
548	usb_fill_int_urb(urb, dev: udev, usb_rcvintpipe(udev, EP_INT_IN),
549	transfer_buffer: intr->buffer, buffer_length: USB_MAX_EP_INT_BUFFER,
550	complete_fn: int_urb_complete, context: usb,
551	interval: intr->interval);
552	urb->transfer_dma = intr->buffer_dma;
553	urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
554
555	dev_dbg_f(zd_usb_dev(usb), "submit urb %p\n", intr->urb);
556	r = usb_submit_urb(urb, GFP_KERNEL);
557	if (r) {
558	dev_dbg_f(zd_usb_dev(usb),
559	"Couldn't submit urb. Error number %d\n", r);
560	goto error;
561	}
562
563	return 0;
564	error:
565	usb_free_coherent(dev: udev, size: USB_MAX_EP_INT_BUFFER,
566	addr: intr->buffer, dma: intr->buffer_dma);
567	error_set_urb_null:
568	spin_lock_irq(lock: &intr->lock);
569	intr->urb = NULL;
570	spin_unlock_irq(lock: &intr->lock);
571	error_free_urb:
572	usb_free_urb(urb);
573	out:
574	return r;
575	}
576
577	void zd_usb_disable_int(struct zd_usb *usb)
578	{
579	unsigned long flags;
580	struct usb_device *udev = zd_usb_to_usbdev(usb);
581	struct zd_usb_interrupt *intr = &usb->intr;
582	struct urb *urb;
583	void *buffer;
584	dma_addr_t buffer_dma;
585
586	spin_lock_irqsave(&intr->lock, flags);
587	urb = intr->urb;
588	if (!urb) {
589	spin_unlock_irqrestore(lock: &intr->lock, flags);
590	return;
591	}
592	intr->urb = NULL;
593	buffer = intr->buffer;
594	buffer_dma = intr->buffer_dma;
595	intr->buffer = NULL;
596	spin_unlock_irqrestore(lock: &intr->lock, flags);
597
598	usb_kill_urb(urb);
599	dev_dbg_f(zd_usb_dev(usb), "urb %p killed\n", urb);
600	usb_free_urb(urb);
601
602	usb_free_coherent(dev: udev, size: USB_MAX_EP_INT_BUFFER, addr: buffer, dma: buffer_dma);
603	}
604
605	static void handle_rx_packet(struct zd_usb *usb, const u8 *buffer,
606	unsigned int length)
607	{
608	int i;
609	const struct rx_length_info *length_info;
610
611	if (length < sizeof(struct rx_length_info)) {
612	/* It's not a complete packet anyhow. */
613	dev_dbg_f(zd_usb_dev(usb), "invalid, small RX packet : %d\n",
614	length);
615	return;
616	}
617	length_info = (struct rx_length_info *)
618	(buffer + length - sizeof(struct rx_length_info));
619
620	/* It might be that three frames are merged into a single URB
621	* transaction. We have to check for the length info tag.
622	*
623	* While testing we discovered that length_info might be unaligned,
624	* because if USB transactions are merged, the last packet will not
625	* be padded. Unaligned access might also happen if the length_info
626	* structure is not present.
627	*/
628	if (get_unaligned_le16(p: &length_info->tag) == RX_LENGTH_INFO_TAG)
629	{
630	unsigned int l, k, n;
631	for (i = 0, l = 0;; i++) {
632	k = get_unaligned_le16(p: &length_info->length[i]);
633	if (k == 0)
634	return;
635	n = l+k;
636	if (n > length)
637	return;
638	zd_mac_rx(hw: zd_usb_to_hw(usb), buffer: buffer+l, length: k);
639	if (i >= 2)
640	return;
641	l = (n+3) & ~3;
642	}
643	} else {
644	zd_mac_rx(hw: zd_usb_to_hw(usb), buffer, length);
645	}
646	}
647
648	static void rx_urb_complete(struct urb *urb)
649	{
650	int r;
651	struct zd_usb *usb;
652	struct zd_usb_rx *rx;
653	const u8 *buffer;
654	unsigned int length;
655	unsigned long flags;
656
657	switch (urb->status) {
658	case 0:
659	break;
660	case -ESHUTDOWN:
661	case -EINVAL:
662	case -ENODEV:
663	case -ENOENT:
664	case -ECONNRESET:
665	case -EPIPE:
666	dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
667	return;
668	default:
669	dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
670	goto resubmit;
671	}
672
673	buffer = urb->transfer_buffer;
674	length = urb->actual_length;
675	usb = urb->context;
676	rx = &usb->rx;
677
678	tasklet_schedule(t: &rx->reset_timer_tasklet);
679
680	if (length%rx->usb_packet_size > rx->usb_packet_size-4) {
681	/* If there is an old first fragment, we don't care. */
682	dev_dbg_f(urb_dev(urb), "*** first fragment ***\n");
683	ZD_ASSERT(length <= ARRAY_SIZE(rx->fragment));
684	spin_lock_irqsave(&rx->lock, flags);
685	memcpy(rx->fragment, buffer, length);
686	rx->fragment_length = length;
687	spin_unlock_irqrestore(lock: &rx->lock, flags);
688	goto resubmit;
689	}
690
691	spin_lock_irqsave(&rx->lock, flags);
692	if (rx->fragment_length > 0) {
693	/* We are on a second fragment, we believe */
694	ZD_ASSERT(length + rx->fragment_length <=
695	ARRAY_SIZE(rx->fragment));
696	dev_dbg_f(urb_dev(urb), "*** second fragment ***\n");
697	memcpy(rx->fragment+rx->fragment_length, buffer, length);
698	handle_rx_packet(usb, buffer: rx->fragment,
699	length: rx->fragment_length + length);
700	rx->fragment_length = 0;
701	spin_unlock_irqrestore(lock: &rx->lock, flags);
702	} else {
703	spin_unlock_irqrestore(lock: &rx->lock, flags);
704	handle_rx_packet(usb, buffer, length);
705	}
706
707	resubmit:
708	r = usb_submit_urb(urb, GFP_ATOMIC);
709	if (r)
710	dev_dbg_f(urb_dev(urb), "urb %p resubmit error %d\n", urb, r);
711	}
712
713	static struct urb *alloc_rx_urb(struct zd_usb *usb)
714	{
715	struct usb_device *udev = zd_usb_to_usbdev(usb);
716	struct urb *urb;
717	void *buffer;
718
719	urb = usb_alloc_urb(iso_packets: 0, GFP_KERNEL);
720	if (!urb)
721	return NULL;
722	buffer = usb_alloc_coherent(dev: udev, size: USB_MAX_RX_SIZE, GFP_KERNEL,
723	dma: &urb->transfer_dma);
724	if (!buffer) {
725	usb_free_urb(urb);
726	return NULL;
727	}
728
729	usb_fill_bulk_urb(urb, dev: udev, usb_rcvbulkpipe(udev, EP_DATA_IN),
730	transfer_buffer: buffer, buffer_length: USB_MAX_RX_SIZE,
731	complete_fn: rx_urb_complete, context: usb);
732	urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
733
734	return urb;
735	}
736
737	static void free_rx_urb(struct urb *urb)
738	{
739	if (!urb)
740	return;
741	usb_free_coherent(dev: urb->dev, size: urb->transfer_buffer_length,
742	addr: urb->transfer_buffer, dma: urb->transfer_dma);
743	usb_free_urb(urb);
744	}
745
746	static int __zd_usb_enable_rx(struct zd_usb *usb)
747	{
748	int i, r;
749	struct zd_usb_rx *rx = &usb->rx;
750	struct urb **urbs;
751
752	dev_dbg_f(zd_usb_dev(usb), "\n");
753
754	r = -ENOMEM;
755	urbs = kcalloc(RX_URBS_COUNT, size: sizeof(struct urb *), GFP_KERNEL);
756	if (!urbs)
757	goto error;
758	for (i = 0; i < RX_URBS_COUNT; i++) {
759	urbs[i] = alloc_rx_urb(usb);
760	if (!urbs[i])
761	goto error;
762	}
763
764	ZD_ASSERT(!irqs_disabled());
765	spin_lock_irq(lock: &rx->lock);
766	if (rx->urbs) {
767	spin_unlock_irq(lock: &rx->lock);
768	r = 0;
769	goto error;
770	}
771	rx->urbs = urbs;
772	rx->urbs_count = RX_URBS_COUNT;
773	spin_unlock_irq(lock: &rx->lock);
774
775	for (i = 0; i < RX_URBS_COUNT; i++) {
776	r = usb_submit_urb(urb: urbs[i], GFP_KERNEL);
777	if (r)
778	goto error_submit;
779	}
780
781	return 0;
782	error_submit:
783	for (i = 0; i < RX_URBS_COUNT; i++) {
784	usb_kill_urb(urb: urbs[i]);
785	}
786	spin_lock_irq(lock: &rx->lock);
787	rx->urbs = NULL;
788	rx->urbs_count = 0;
789	spin_unlock_irq(lock: &rx->lock);
790	error:
791	if (urbs) {
792	for (i = 0; i < RX_URBS_COUNT; i++)
793	free_rx_urb(urb: urbs[i]);
794	}
795	return r;
796	}
797
798	int zd_usb_enable_rx(struct zd_usb *usb)
799	{
800	int r;
801	struct zd_usb_rx *rx = &usb->rx;
802
803	mutex_lock(&rx->setup_mutex);
804	r = __zd_usb_enable_rx(usb);
805	mutex_unlock(lock: &rx->setup_mutex);
806
807	zd_usb_reset_rx_idle_timer(usb);
808
809	return r;
810	}
811
812	static void __zd_usb_disable_rx(struct zd_usb *usb)
813	{
814	int i;
815	unsigned long flags;
816	struct urb **urbs;
817	unsigned int count;
818	struct zd_usb_rx *rx = &usb->rx;
819
820	spin_lock_irqsave(&rx->lock, flags);
821	urbs = rx->urbs;
822	count = rx->urbs_count;
823	spin_unlock_irqrestore(lock: &rx->lock, flags);
824	if (!urbs)
825	return;
826
827	for (i = 0; i < count; i++) {
828	usb_kill_urb(urb: urbs[i]);
829	free_rx_urb(urb: urbs[i]);
830	}
831	kfree(objp: urbs);
832
833	spin_lock_irqsave(&rx->lock, flags);
834	rx->urbs = NULL;
835	rx->urbs_count = 0;
836	spin_unlock_irqrestore(lock: &rx->lock, flags);
837	}
838
839	void zd_usb_disable_rx(struct zd_usb *usb)
840	{
841	struct zd_usb_rx *rx = &usb->rx;
842
843	mutex_lock(&rx->setup_mutex);
844	__zd_usb_disable_rx(usb);
845	mutex_unlock(lock: &rx->setup_mutex);
846
847	tasklet_kill(t: &rx->reset_timer_tasklet);
848	cancel_delayed_work_sync(dwork: &rx->idle_work);
849	}
850
851	static void zd_usb_reset_rx(struct zd_usb *usb)
852	{
853	bool do_reset;
854	struct zd_usb_rx *rx = &usb->rx;
855	unsigned long flags;
856
857	mutex_lock(&rx->setup_mutex);
858
859	spin_lock_irqsave(&rx->lock, flags);
860	do_reset = rx->urbs != NULL;
861	spin_unlock_irqrestore(lock: &rx->lock, flags);
862
863	if (do_reset) {
864	__zd_usb_disable_rx(usb);
865	__zd_usb_enable_rx(usb);
866	}
867
868	mutex_unlock(lock: &rx->setup_mutex);
869
870	if (do_reset)
871	zd_usb_reset_rx_idle_timer(usb);
872	}
873
874	/**
875	* zd_usb_disable_tx - disable transmission
876	* @usb: the zd1211rw-private USB structure
877	*
878	* Frees all URBs in the free list and marks the transmission as disabled.
879	*/
880	void zd_usb_disable_tx(struct zd_usb *usb)
881	{
882	struct zd_usb_tx *tx = &usb->tx;
883	unsigned long flags;
884
885	atomic_set(v: &tx->enabled, i: 0);
886
887	/* kill all submitted tx-urbs */
888	usb_kill_anchored_urbs(anchor: &tx->submitted);
889
890	spin_lock_irqsave(&tx->lock, flags);
891	WARN_ON(!skb_queue_empty(&tx->submitted_skbs));
892	WARN_ON(tx->submitted_urbs != 0);
893	tx->submitted_urbs = 0;
894	spin_unlock_irqrestore(lock: &tx->lock, flags);
895
896	/* The stopped state is ignored, relying on ieee80211_wake_queues()
897	* in a potentionally following zd_usb_enable_tx().
898	*/
899	}
900
901	/**
902	* zd_usb_enable_tx - enables transmission
903	* @usb: a &struct zd_usb pointer
904	*
905	* This function enables transmission and prepares the &zd_usb_tx data
906	* structure.
907	*/
908	void zd_usb_enable_tx(struct zd_usb *usb)
909	{
910	unsigned long flags;
911	struct zd_usb_tx *tx = &usb->tx;
912
913	spin_lock_irqsave(&tx->lock, flags);
914	atomic_set(v: &tx->enabled, i: 1);
915	tx->submitted_urbs = 0;
916	ieee80211_wake_queues(hw: zd_usb_to_hw(usb));
917	tx->stopped = 0;
918	spin_unlock_irqrestore(lock: &tx->lock, flags);
919	}
920
921	static void tx_dec_submitted_urbs(struct zd_usb *usb)
922	{
923	struct zd_usb_tx *tx = &usb->tx;
924	unsigned long flags;
925
926	spin_lock_irqsave(&tx->lock, flags);
927	--tx->submitted_urbs;
928	if (tx->stopped && tx->submitted_urbs <= ZD_USB_TX_LOW) {
929	ieee80211_wake_queues(hw: zd_usb_to_hw(usb));
930	tx->stopped = 0;
931	}
932	spin_unlock_irqrestore(lock: &tx->lock, flags);
933	}
934
935	static void tx_inc_submitted_urbs(struct zd_usb *usb)
936	{
937	struct zd_usb_tx *tx = &usb->tx;
938	unsigned long flags;
939
940	spin_lock_irqsave(&tx->lock, flags);
941	++tx->submitted_urbs;
942	if (!tx->stopped && tx->submitted_urbs > ZD_USB_TX_HIGH) {
943	ieee80211_stop_queues(hw: zd_usb_to_hw(usb));
944	tx->stopped = 1;
945	}
946	spin_unlock_irqrestore(lock: &tx->lock, flags);
947	}
948
949	/**
950	* tx_urb_complete - completes the execution of an URB
951	* @urb: a URB
952	*
953	* This function is called if the URB has been transferred to a device or an
954	* error has happened.
955	*/
956	static void tx_urb_complete(struct urb *urb)
957	{
958	int r;
959	struct sk_buff *skb;
960	struct ieee80211_tx_info *info;
961	struct zd_usb *usb;
962	struct zd_usb_tx *tx;
963
964	skb = (struct sk_buff *)urb->context;
965	info = IEEE80211_SKB_CB(skb);
966	/*
967	* grab 'usb' pointer before handing off the skb (since
968	* it might be freed by zd_mac_tx_to_dev or mac80211)
969	*/
970	usb = &zd_hw_mac(hw: info->rate_driver_data[0])->chip.usb;
971	tx = &usb->tx;
972
973	switch (urb->status) {
974	case 0:
975	break;
976	case -ESHUTDOWN:
977	case -EINVAL:
978	case -ENODEV:
979	case -ENOENT:
980	case -ECONNRESET:
981	case -EPIPE:
982	dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
983	break;
984	default:
985	dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
986	goto resubmit;
987	}
988	free_urb:
989	skb_unlink(skb, list: &usb->tx.submitted_skbs);
990	zd_mac_tx_to_dev(skb, error: urb->status);
991	usb_free_urb(urb);
992	tx_dec_submitted_urbs(usb);
993	return;
994	resubmit:
995	usb_anchor_urb(urb, anchor: &tx->submitted);
996	r = usb_submit_urb(urb, GFP_ATOMIC);
997	if (r) {
998	usb_unanchor_urb(urb);
999	dev_dbg_f(urb_dev(urb), "error resubmit urb %p %d\n", urb, r);
1000	goto free_urb;
1001	}
1002	}
1003
1004	/**
1005	* zd_usb_tx: initiates transfer of a frame of the device
1006	*
1007	* @usb: the zd1211rw-private USB structure
1008	* @skb: a &struct sk_buff pointer
1009	*
1010	* This function transmits a frame to the device. It doesn't wait for
1011	* completion. The frame must contain the control set and have all the
1012	* control set information available.
1013	*
1014	* The function returns 0 if the transfer has been successfully initiated.
1015	*/
1016	int zd_usb_tx(struct zd_usb *usb, struct sk_buff *skb)
1017	{
1018	int r;
1019	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1020	struct usb_device *udev = zd_usb_to_usbdev(usb);
1021	struct urb *urb;
1022	struct zd_usb_tx *tx = &usb->tx;
1023
1024	if (!atomic_read(v: &tx->enabled)) {
1025	r = -ENOENT;
1026	goto out;
1027	}
1028
1029	urb = usb_alloc_urb(iso_packets: 0, GFP_ATOMIC);
1030	if (!urb) {
1031	r = -ENOMEM;
1032	goto out;
1033	}
1034
1035	usb_fill_bulk_urb(urb, dev: udev, usb_sndbulkpipe(udev, EP_DATA_OUT),
1036	transfer_buffer: skb->data, buffer_length: skb->len, complete_fn: tx_urb_complete, context: skb);
1037
1038	info->rate_driver_data[1] = (void *)jiffies;
1039	skb_queue_tail(list: &tx->submitted_skbs, newsk: skb);
1040	usb_anchor_urb(urb, anchor: &tx->submitted);
1041
1042	r = usb_submit_urb(urb, GFP_ATOMIC);
1043	if (r) {
1044	dev_dbg_f(zd_usb_dev(usb), "error submit urb %p %d\n", urb, r);
1045	usb_unanchor_urb(urb);
1046	skb_unlink(skb, list: &tx->submitted_skbs);
1047	goto error;
1048	}
1049	tx_inc_submitted_urbs(usb);
1050	return 0;
1051	error:
1052	usb_free_urb(urb);
1053	out:
1054	return r;
1055	}
1056
1057	static bool zd_tx_timeout(struct zd_usb *usb)
1058	{
1059	struct zd_usb_tx *tx = &usb->tx;
1060	struct sk_buff_head *q = &tx->submitted_skbs;
1061	struct sk_buff *skb, *skbnext;
1062	struct ieee80211_tx_info *info;
1063	unsigned long flags, trans_start;
1064	bool have_timedout = false;
1065
1066	spin_lock_irqsave(&q->lock, flags);
1067	skb_queue_walk_safe(q, skb, skbnext) {
1068	info = IEEE80211_SKB_CB(skb);
1069	trans_start = (unsigned long)info->rate_driver_data[1];
1070
1071	if (time_is_before_jiffies(trans_start + ZD_TX_TIMEOUT)) {
1072	have_timedout = true;
1073	break;
1074	}
1075	}
1076	spin_unlock_irqrestore(lock: &q->lock, flags);
1077
1078	return have_timedout;
1079	}
1080
1081	static void zd_tx_watchdog_handler(struct work_struct *work)
1082	{
1083	struct zd_usb *usb =
1084	container_of(work, struct zd_usb, tx.watchdog_work.work);
1085	struct zd_usb_tx *tx = &usb->tx;
1086
1087	if (!atomic_read(v: &tx->enabled) || !tx->watchdog_enabled)
1088	goto out;
1089	if (!zd_tx_timeout(usb))
1090	goto out;
1091
1092	/* TX halted, try reset */
1093	dev_warn(zd_usb_dev(usb), "TX-stall detected, resetting device...");
1094
1095	usb_queue_reset_device(dev: usb->intf);
1096
1097	/* reset will stop this worker, don't rearm */
1098	return;
1099	out:
1100	queue_delayed_work(wq: zd_workqueue, dwork: &tx->watchdog_work,
1101	ZD_TX_WATCHDOG_INTERVAL);
1102	}
1103
1104	void zd_tx_watchdog_enable(struct zd_usb *usb)
1105	{
1106	struct zd_usb_tx *tx = &usb->tx;
1107
1108	if (!tx->watchdog_enabled) {
1109	dev_dbg_f(zd_usb_dev(usb), "\n");
1110	queue_delayed_work(wq: zd_workqueue, dwork: &tx->watchdog_work,
1111	ZD_TX_WATCHDOG_INTERVAL);
1112	tx->watchdog_enabled = 1;
1113	}
1114	}
1115
1116	void zd_tx_watchdog_disable(struct zd_usb *usb)
1117	{
1118	struct zd_usb_tx *tx = &usb->tx;
1119
1120	if (tx->watchdog_enabled) {
1121	dev_dbg_f(zd_usb_dev(usb), "\n");
1122	tx->watchdog_enabled = 0;
1123	cancel_delayed_work_sync(dwork: &tx->watchdog_work);
1124	}
1125	}
1126
1127	static void zd_rx_idle_timer_handler(struct work_struct *work)
1128	{
1129	struct zd_usb *usb =
1130	container_of(work, struct zd_usb, rx.idle_work.work);
1131	struct zd_mac *mac = zd_usb_to_mac(usb);
1132
1133	if (!test_bit(ZD_DEVICE_RUNNING, &mac->flags))
1134	return;
1135
1136	dev_dbg_f(zd_usb_dev(usb), "\n");
1137
1138	/* 30 seconds since last rx, reset rx */
1139	zd_usb_reset_rx(usb);
1140	}
1141
1142	static void zd_usb_reset_rx_idle_timer_tasklet(struct tasklet_struct *t)
1143	{
1144	struct zd_usb *usb = from_tasklet(usb, t, rx.reset_timer_tasklet);
1145
1146	zd_usb_reset_rx_idle_timer(usb);
1147	}
1148
1149	void zd_usb_reset_rx_idle_timer(struct zd_usb *usb)
1150	{
1151	struct zd_usb_rx *rx = &usb->rx;
1152
1153	mod_delayed_work(wq: zd_workqueue, dwork: &rx->idle_work, ZD_RX_IDLE_INTERVAL);
1154	}
1155
1156	static inline void init_usb_interrupt(struct zd_usb *usb)
1157	{
1158	struct zd_usb_interrupt *intr = &usb->intr;
1159
1160	spin_lock_init(&intr->lock);
1161	intr->interval = int_urb_interval(udev: zd_usb_to_usbdev(usb));
1162	init_completion(x: &intr->read_regs.completion);
1163	atomic_set(v: &intr->read_regs_enabled, i: 0);
1164	intr->read_regs.cr_int_addr = cpu_to_le16((u16)CR_INTERRUPT);
1165	}
1166
1167	static inline void init_usb_rx(struct zd_usb *usb)
1168	{
1169	struct zd_usb_rx *rx = &usb->rx;
1170
1171	spin_lock_init(&rx->lock);
1172	mutex_init(&rx->setup_mutex);
1173	if (interface_to_usbdev(usb->intf)->speed == USB_SPEED_HIGH) {
1174	rx->usb_packet_size = 512;
1175	} else {
1176	rx->usb_packet_size = 64;
1177	}
1178	ZD_ASSERT(rx->fragment_length == 0);
1179	INIT_DELAYED_WORK(&rx->idle_work, zd_rx_idle_timer_handler);
1180	rx->reset_timer_tasklet.func = (void (*))
1181	zd_usb_reset_rx_idle_timer_tasklet;
1182	rx->reset_timer_tasklet.data = (unsigned long)&rx->reset_timer_tasklet;
1183	}
1184
1185	static inline void init_usb_tx(struct zd_usb *usb)
1186	{
1187	struct zd_usb_tx *tx = &usb->tx;
1188
1189	spin_lock_init(&tx->lock);
1190	atomic_set(v: &tx->enabled, i: 0);
1191	tx->stopped = 0;
1192	skb_queue_head_init(list: &tx->submitted_skbs);
1193	init_usb_anchor(anchor: &tx->submitted);
1194	tx->submitted_urbs = 0;
1195	tx->watchdog_enabled = 0;
1196	INIT_DELAYED_WORK(&tx->watchdog_work, zd_tx_watchdog_handler);
1197	}
1198
1199	void zd_usb_init(struct zd_usb *usb, struct ieee80211_hw *hw,
1200	struct usb_interface *intf)
1201	{
1202	memset(usb, 0, sizeof(*usb));
1203	usb->intf = usb_get_intf(intf);
1204	usb_set_intfdata(intf: usb->intf, data: hw);
1205	init_usb_anchor(anchor: &usb->submitted_cmds);
1206	init_usb_interrupt(usb);
1207	init_usb_tx(usb);
1208	init_usb_rx(usb);
1209	}
1210
1211	void zd_usb_clear(struct zd_usb *usb)
1212	{
1213	usb_set_intfdata(intf: usb->intf, NULL);
1214	usb_put_intf(intf: usb->intf);
1215	ZD_MEMCLEAR(usb, sizeof(*usb));
1216	/* FIXME: usb_interrupt, usb_tx, usb_rx? */
1217	}
1218
1219	static const char *speed(enum usb_device_speed speed)
1220	{
1221	switch (speed) {
1222	case USB_SPEED_LOW:
1223	return "low";
1224	case USB_SPEED_FULL:
1225	return "full";
1226	case USB_SPEED_HIGH:
1227	return "high";
1228	default:
1229	return "unknown speed";
1230	}
1231	}
1232
1233	static int scnprint_id(struct usb_device *udev, char *buffer, size_t size)
1234	{
1235	return scnprintf(buf: buffer, size, fmt: "%04hx:%04hx v%04hx %s",
1236	le16_to_cpu(udev->descriptor.idVendor),
1237	le16_to_cpu(udev->descriptor.idProduct),
1238	get_bcdDevice(udev),
1239	speed(speed: udev->speed));
1240	}
1241
1242	int zd_usb_scnprint_id(struct zd_usb *usb, char *buffer, size_t size)
1243	{
1244	struct usb_device *udev = interface_to_usbdev(usb->intf);
1245	return scnprint_id(udev, buffer, size);
1246	}
1247
1248	#ifdef DEBUG
1249	static void print_id(struct usb_device *udev)
1250	{
1251	char buffer[40];
1252
1253	scnprint_id(udev, buffer, size: sizeof(buffer));
1254	buffer[sizeof(buffer)-1] = 0;
1255	dev_dbg_f(&udev->dev, "%s\n", buffer);
1256	}
1257	#else
1258	#define print_id(udev) do { } while (0)
1259	#endif
1260
1261	static int eject_installer(struct usb_interface *intf)
1262	{
1263	struct usb_device *udev = interface_to_usbdev(intf);
1264	struct usb_host_interface *iface_desc = intf->cur_altsetting;
1265	struct usb_endpoint_descriptor *endpoint;
1266	unsigned char *cmd;
1267	u8 bulk_out_ep;
1268	int r;
1269
1270	if (iface_desc->desc.bNumEndpoints < 2)
1271	return -ENODEV;
1272
1273	/* Find bulk out endpoint */
1274	for (r = 1; r >= 0; r--) {
1275	endpoint = &iface_desc->endpoint[r].desc;
1276	if (usb_endpoint_dir_out(epd: endpoint) &&
1277	usb_endpoint_xfer_bulk(epd: endpoint)) {
1278	bulk_out_ep = endpoint->bEndpointAddress;
1279	break;
1280	}
1281	}
1282	if (r == -1) {
1283	dev_err(&udev->dev,
1284	"zd1211rw: Could not find bulk out endpoint\n");
1285	return -ENODEV;
1286	}
1287
1288	cmd = kzalloc(size: 31, GFP_KERNEL);
1289	if (cmd == NULL)
1290	return -ENODEV;
1291
1292	/* USB bulk command block */
1293	cmd[0] = 0x55; /* bulk command signature */
1294	cmd[1] = 0x53; /* bulk command signature */
1295	cmd[2] = 0x42; /* bulk command signature */
1296	cmd[3] = 0x43; /* bulk command signature */
1297	cmd[14] = 6; /* command length */
1298
1299	cmd[15] = 0x1b; /* SCSI command: START STOP UNIT */
1300	cmd[19] = 0x2; /* eject disc */
1301
1302	dev_info(&udev->dev, "Ejecting virtual installer media...\n");
1303	r = usb_bulk_msg(usb_dev: udev, usb_sndbulkpipe(udev, bulk_out_ep),
1304	data: cmd, len: 31, NULL, timeout: 2000);
1305	kfree(objp: cmd);
1306	if (r)
1307	return r;
1308
1309	/* At this point, the device disconnects and reconnects with the real
1310	* ID numbers. */
1311
1312	usb_set_intfdata(intf, NULL);
1313	return 0;
1314	}
1315
1316	int zd_usb_init_hw(struct zd_usb *usb)
1317	{
1318	int r;
1319	struct zd_mac *mac = zd_usb_to_mac(usb);
1320
1321	dev_dbg_f(zd_usb_dev(usb), "\n");
1322
1323	r = upload_firmware(usb);
1324	if (r) {
1325	dev_err(zd_usb_dev(usb),
1326	"couldn't load firmware. Error number %d\n", r);
1327	return r;
1328	}
1329
1330	r = usb_reset_configuration(dev: zd_usb_to_usbdev(usb));
1331	if (r) {
1332	dev_dbg_f(zd_usb_dev(usb),
1333	"couldn't reset configuration. Error number %d\n", r);
1334	return r;
1335	}
1336
1337	r = zd_mac_init_hw(hw: mac->hw);
1338	if (r) {
1339	dev_dbg_f(zd_usb_dev(usb),
1340	"couldn't initialize mac. Error number %d\n", r);
1341	return r;
1342	}
1343
1344	usb->initialized = 1;
1345	return 0;
1346	}
1347
1348	static int probe(struct usb_interface *intf, const struct usb_device_id *id)
1349	{
1350	int r;
1351	struct usb_device *udev = interface_to_usbdev(intf);
1352	struct zd_usb *usb;
1353	struct ieee80211_hw *hw = NULL;
1354
1355	print_id(udev);
1356
1357	if (id->driver_info & DEVICE_INSTALLER)
1358	return eject_installer(intf);
1359
1360	switch (udev->speed) {
1361	case USB_SPEED_LOW:
1362	case USB_SPEED_FULL:
1363	case USB_SPEED_HIGH:
1364	break;
1365	default:
1366	dev_dbg_f(&intf->dev, "Unknown USB speed\n");
1367	r = -ENODEV;
1368	goto error;
1369	}
1370
1371	r = usb_reset_device(dev: udev);
1372	if (r) {
1373	dev_err(&intf->dev,
1374	"couldn't reset usb device. Error number %d\n", r);
1375	goto error;
1376	}
1377
1378	hw = zd_mac_alloc_hw(intf);
1379	if (hw == NULL) {
1380	r = -ENOMEM;
1381	goto error;
1382	}
1383
1384	usb = &zd_hw_mac(hw)->chip.usb;
1385	usb->is_zd1211b = (id->driver_info == DEVICE_ZD1211B) != 0;
1386
1387	r = zd_mac_preinit_hw(hw);
1388	if (r) {
1389	dev_dbg_f(&intf->dev,
1390	"couldn't initialize mac. Error number %d\n", r);
1391	goto error;
1392	}
1393
1394	r = ieee80211_register_hw(hw);
1395	if (r) {
1396	dev_dbg_f(&intf->dev,
1397	"couldn't register device. Error number %d\n", r);
1398	goto error;
1399	}
1400
1401	dev_dbg_f(&intf->dev, "successful\n");
1402	dev_info(&intf->dev, "%s\n", wiphy_name(hw->wiphy));
1403	return 0;
1404	error:
1405	usb_reset_device(interface_to_usbdev(intf));
1406	if (hw) {
1407	zd_mac_clear(mac: zd_hw_mac(hw));
1408	ieee80211_free_hw(hw);
1409	}
1410	return r;
1411	}
1412
1413	static void disconnect(struct usb_interface *intf)
1414	{
1415	struct ieee80211_hw *hw = zd_intf_to_hw(intf);
1416	struct zd_mac *mac;
1417	struct zd_usb *usb;
1418
1419	/* Either something really bad happened, or we're just dealing with
1420	* a DEVICE_INSTALLER. */
1421	if (hw == NULL)
1422	return;
1423
1424	mac = zd_hw_mac(hw);
1425	usb = &mac->chip.usb;
1426
1427	dev_dbg_f(zd_usb_dev(usb), "\n");
1428
1429	ieee80211_unregister_hw(hw);
1430
1431	/* Just in case something has gone wrong! */
1432	zd_usb_disable_tx(usb);
1433	zd_usb_disable_rx(usb);
1434	zd_usb_disable_int(usb);
1435
1436	/* If the disconnect has been caused by a removal of the
1437	* driver module, the reset allows reloading of the driver. If the
1438	* reset will not be executed here, the upload of the firmware in the
1439	* probe function caused by the reloading of the driver will fail.
1440	*/
1441	usb_reset_device(interface_to_usbdev(intf));
1442
1443	zd_mac_clear(mac);
1444	ieee80211_free_hw(hw);
1445	dev_dbg(&intf->dev, "disconnected\n");
1446	}
1447
1448	static void zd_usb_resume(struct zd_usb *usb)
1449	{
1450	struct zd_mac *mac = zd_usb_to_mac(usb);
1451	int r;
1452
1453	dev_dbg_f(zd_usb_dev(usb), "\n");
1454
1455	r = zd_op_start(hw: zd_usb_to_hw(usb));
1456	if (r < 0) {
1457	dev_warn(zd_usb_dev(usb), "Device resume failed "
1458	"with error code %d. Retrying...\n", r);
1459	if (usb->was_running)
1460	set_bit(nr: ZD_DEVICE_RUNNING, addr: &mac->flags);
1461	usb_queue_reset_device(dev: usb->intf);
1462	return;
1463	}
1464
1465	if (mac->type != NL80211_IFTYPE_UNSPECIFIED) {
1466	r = zd_restore_settings(mac);
1467	if (r < 0) {
1468	dev_dbg(zd_usb_dev(usb),
1469	"failed to restore settings, %d\n", r);
1470	return;
1471	}
1472	}
1473	}
1474
1475	static void zd_usb_stop(struct zd_usb *usb)
1476	{
1477	dev_dbg_f(zd_usb_dev(usb), "\n");
1478
1479	zd_op_stop(hw: zd_usb_to_hw(usb));
1480
1481	zd_usb_disable_tx(usb);
1482	zd_usb_disable_rx(usb);
1483	zd_usb_disable_int(usb);
1484
1485	usb->initialized = 0;
1486	}
1487
1488	static int pre_reset(struct usb_interface *intf)
1489	{
1490	struct ieee80211_hw *hw = usb_get_intfdata(intf);
1491	struct zd_mac *mac;
1492	struct zd_usb *usb;
1493
1494	if (!hw || intf->condition != USB_INTERFACE_BOUND)
1495	return 0;
1496
1497	mac = zd_hw_mac(hw);
1498	usb = &mac->chip.usb;
1499
1500	usb->was_running = test_bit(ZD_DEVICE_RUNNING, &mac->flags);
1501
1502	zd_usb_stop(usb);
1503
1504	mutex_lock(&mac->chip.mutex);
1505	return 0;
1506	}
1507
1508	static int post_reset(struct usb_interface *intf)
1509	{
1510	struct ieee80211_hw *hw = usb_get_intfdata(intf);
1511	struct zd_mac *mac;
1512	struct zd_usb *usb;
1513
1514	if (!hw || intf->condition != USB_INTERFACE_BOUND)
1515	return 0;
1516
1517	mac = zd_hw_mac(hw);
1518	usb = &mac->chip.usb;
1519
1520	mutex_unlock(lock: &mac->chip.mutex);
1521
1522	if (usb->was_running)
1523	zd_usb_resume(usb);
1524	return 0;
1525	}
1526
1527	static struct usb_driver driver = {
1528	.name = KBUILD_MODNAME,
1529	.id_table = usb_ids,
1530	.probe = probe,
1531	.disconnect = disconnect,
1532	.pre_reset = pre_reset,
1533	.post_reset = post_reset,
1534	.disable_hub_initiated_lpm = 1,
1535	};
1536
1537	struct workqueue_struct *zd_workqueue;
1538
1539	static int __init usb_init(void)
1540	{
1541	int r;
1542
1543	pr_debug("%s usb_init()\n", driver.name);
1544
1545	zd_workqueue = create_singlethread_workqueue(driver.name);
1546	if (zd_workqueue == NULL) {
1547	pr_err("%s couldn't create workqueue\n", driver.name);
1548	return -ENOMEM;
1549	}
1550
1551	r = usb_register(&driver);
1552	if (r) {
1553	destroy_workqueue(wq: zd_workqueue);
1554	pr_err("%s usb_register() failed. Error number %d\n",
1555	driver.name, r);
1556	return r;
1557	}
1558
1559	pr_debug("%s initialized\n", driver.name);
1560	return 0;
1561	}
1562
1563	static void __exit usb_exit(void)
1564	{
1565	pr_debug("%s usb_exit()\n", driver.name);
1566	usb_deregister(&driver);
1567	destroy_workqueue(wq: zd_workqueue);
1568	}
1569
1570	module_init(usb_init);
1571	module_exit(usb_exit);
1572
1573	static int zd_ep_regs_out_msg(struct usb_device *udev, void *data, int len,
1574	int *actual_length, int timeout)
1575	{
1576	/* In USB 2.0 mode EP_REGS_OUT endpoint is interrupt type. However in
1577	* USB 1.1 mode endpoint is bulk. Select correct type URB by endpoint
1578	* descriptor.
1579	*/
1580	struct usb_host_endpoint *ep;
1581	unsigned int pipe;
1582
1583	pipe = usb_sndintpipe(udev, EP_REGS_OUT);
1584	ep = usb_pipe_endpoint(dev: udev, pipe);
1585	if (!ep)
1586	return -EINVAL;
1587
1588	if (usb_endpoint_xfer_int(epd: &ep->desc)) {
1589	return usb_interrupt_msg(usb_dev: udev, pipe, data, len,
1590	actual_length, timeout);
1591	} else {
1592	pipe = usb_sndbulkpipe(udev, EP_REGS_OUT);
1593	return usb_bulk_msg(usb_dev: udev, pipe, data, len, actual_length,
1594	timeout);
1595	}
1596	}
1597
1598	static void prepare_read_regs_int(struct zd_usb *usb,
1599	struct usb_req_read_regs *req,
1600	unsigned int count)
1601	{
1602	struct zd_usb_interrupt *intr = &usb->intr;
1603
1604	spin_lock_irq(lock: &intr->lock);
1605	atomic_set(v: &intr->read_regs_enabled, i: 1);
1606	intr->read_regs.req = req;
1607	intr->read_regs.req_count = count;
1608	reinit_completion(x: &intr->read_regs.completion);
1609	spin_unlock_irq(lock: &intr->lock);
1610	}
1611
1612	static void disable_read_regs_int(struct zd_usb *usb)
1613	{
1614	struct zd_usb_interrupt *intr = &usb->intr;
1615
1616	spin_lock_irq(lock: &intr->lock);
1617	atomic_set(v: &intr->read_regs_enabled, i: 0);
1618	spin_unlock_irq(lock: &intr->lock);
1619	}
1620
1621	static bool check_read_regs(struct zd_usb *usb, struct usb_req_read_regs *req,
1622	unsigned int count)
1623	{
1624	int i;
1625	struct zd_usb_interrupt *intr = &usb->intr;
1626	struct read_regs_int *rr = &intr->read_regs;
1627	struct usb_int_regs *regs = (struct usb_int_regs *)rr->buffer;
1628
1629	/* The created block size seems to be larger than expected.
1630	* However results appear to be correct.
1631	*/
1632	if (rr->length < struct_size(regs, regs, count)) {
1633	dev_dbg_f(zd_usb_dev(usb),
1634	"error: actual length %d less than expected %zu\n",
1635	rr->length, struct_size(regs, regs, count));
1636	return false;
1637	}
1638
1639	if (rr->length > sizeof(rr->buffer)) {
1640	dev_dbg_f(zd_usb_dev(usb),
1641	"error: actual length %d exceeds buffer size %zu\n",
1642	rr->length, sizeof(rr->buffer));
1643	return false;
1644	}
1645
1646	for (i = 0; i < count; i++) {
1647	struct reg_data *rd = &regs->regs[i];
1648	if (rd->addr != req->addr[i]) {
1649	dev_dbg_f(zd_usb_dev(usb),
1650	"rd[%d] addr %#06hx expected %#06hx\n", i,
1651	le16_to_cpu(rd->addr),
1652	le16_to_cpu(req->addr[i]));
1653	return false;
1654	}
1655	}
1656
1657	return true;
1658	}
1659
1660	static int get_results(struct zd_usb *usb, u16 *values,
1661	struct usb_req_read_regs *req, unsigned int count,
1662	bool *retry)
1663	{
1664	int r;
1665	int i;
1666	struct zd_usb_interrupt *intr = &usb->intr;
1667	struct read_regs_int *rr = &intr->read_regs;
1668	struct usb_int_regs *regs = (struct usb_int_regs *)rr->buffer;
1669
1670	spin_lock_irq(lock: &intr->lock);
1671
1672	r = -EIO;
1673
1674	/* Read failed because firmware bug? */
1675	*retry = !!intr->read_regs_int_overridden;
1676	if (*retry)
1677	goto error_unlock;
1678
1679	if (!check_read_regs(usb, req, count)) {
1680	dev_dbg_f(zd_usb_dev(usb), "error: invalid read regs\n");
1681	goto error_unlock;
1682	}
1683
1684	for (i = 0; i < count; i++) {
1685	struct reg_data *rd = &regs->regs[i];
1686	values[i] = le16_to_cpu(rd->value);
1687	}
1688
1689	r = 0;
1690	error_unlock:
1691	spin_unlock_irq(lock: &intr->lock);
1692	return r;
1693	}
1694
1695	int zd_usb_ioread16v(struct zd_usb *usb, u16 *values,
1696	const zd_addr_t *addresses, unsigned int count)
1697	{
1698	int r, i, req_len, actual_req_len, try_count = 0;
1699	struct usb_device *udev;
1700	struct usb_req_read_regs *req = NULL;
1701	unsigned long timeout;
1702	bool retry = false;
1703
1704	if (count < 1) {
1705	dev_dbg_f(zd_usb_dev(usb), "error: count is zero\n");
1706	return -EINVAL;
1707	}
1708	if (count > USB_MAX_IOREAD16_COUNT) {
1709	dev_dbg_f(zd_usb_dev(usb),
1710	"error: count %u exceeds possible max %u\n",
1711	count, USB_MAX_IOREAD16_COUNT);
1712	return -EINVAL;
1713	}
1714	if (!usb_int_enabled(usb)) {
1715	dev_dbg_f(zd_usb_dev(usb),
1716	"error: usb interrupt not enabled\n");
1717	return -EWOULDBLOCK;
1718	}
1719
1720	ZD_ASSERT(mutex_is_locked(&zd_usb_to_chip(usb)->mutex));
1721	BUILD_BUG_ON(sizeof(struct usb_req_read_regs) + USB_MAX_IOREAD16_COUNT *
1722	sizeof(__le16) > sizeof(usb->req_buf));
1723	BUG_ON(sizeof(struct usb_req_read_regs) + count * sizeof(__le16) >
1724	sizeof(usb->req_buf));
1725
1726	req_len = sizeof(struct usb_req_read_regs) + count * sizeof(__le16);
1727	req = (void *)usb->req_buf;
1728
1729	req->id = cpu_to_le16(USB_REQ_READ_REGS);
1730	for (i = 0; i < count; i++)
1731	req->addr[i] = cpu_to_le16((u16)addresses[i]);
1732
1733	retry_read:
1734	try_count++;
1735	udev = zd_usb_to_usbdev(usb);
1736	prepare_read_regs_int(usb, req, count);
1737	r = zd_ep_regs_out_msg(udev, data: req, len: req_len, actual_length: &actual_req_len, timeout: 50 /*ms*/);
1738	if (r) {
1739	dev_dbg_f(zd_usb_dev(usb),
1740	"error in zd_ep_regs_out_msg(). Error number %d\n", r);
1741	goto error;
1742	}
1743	if (req_len != actual_req_len) {
1744	dev_dbg_f(zd_usb_dev(usb), "error in zd_ep_regs_out_msg()\n"
1745	" req_len %d != actual_req_len %d\n",
1746	req_len, actual_req_len);
1747	r = -EIO;
1748	goto error;
1749	}
1750
1751	timeout = wait_for_completion_timeout(x: &usb->intr.read_regs.completion,
1752	timeout: msecs_to_jiffies(m: 50));
1753	if (!timeout) {
1754	disable_read_regs_int(usb);
1755	dev_dbg_f(zd_usb_dev(usb), "read timed out\n");
1756	r = -ETIMEDOUT;
1757	goto error;
1758	}
1759
1760	r = get_results(usb, values, req, count, retry: &retry);
1761	if (retry && try_count < 20) {
1762	dev_dbg_f(zd_usb_dev(usb), "read retry, tries so far: %d\n",
1763	try_count);
1764	goto retry_read;
1765	}
1766	error:
1767	return r;
1768	}
1769
1770	static void iowrite16v_urb_complete(struct urb *urb)
1771	{
1772	struct zd_usb *usb = urb->context;
1773
1774	if (urb->status && !usb->cmd_error)
1775	usb->cmd_error = urb->status;
1776
1777	if (!usb->cmd_error &&
1778	urb->actual_length != urb->transfer_buffer_length)
1779	usb->cmd_error = -EIO;
1780	}
1781
1782	static int zd_submit_waiting_urb(struct zd_usb *usb, bool last)
1783	{
1784	int r = 0;
1785	struct urb *urb = usb->urb_async_waiting;
1786
1787	if (!urb)
1788	return 0;
1789
1790	usb->urb_async_waiting = NULL;
1791
1792	if (!last)
1793	urb->transfer_flags |= URB_NO_INTERRUPT;
1794
1795	usb_anchor_urb(urb, anchor: &usb->submitted_cmds);
1796	r = usb_submit_urb(urb, GFP_KERNEL);
1797	if (r) {
1798	usb_unanchor_urb(urb);
1799	dev_dbg_f(zd_usb_dev(usb),
1800	"error in usb_submit_urb(). Error number %d\n", r);
1801	goto error;
1802	}
1803
1804	/* fall-through with r == 0 */
1805	error:
1806	usb_free_urb(urb);
1807	return r;
1808	}
1809
1810	void zd_usb_iowrite16v_async_start(struct zd_usb *usb)
1811	{
1812	ZD_ASSERT(usb_anchor_empty(&usb->submitted_cmds));
1813	ZD_ASSERT(usb->urb_async_waiting == NULL);
1814	ZD_ASSERT(!usb->in_async);
1815
1816	ZD_ASSERT(mutex_is_locked(&zd_usb_to_chip(usb)->mutex));
1817
1818	usb->in_async = 1;
1819	usb->cmd_error = 0;
1820	usb->urb_async_waiting = NULL;
1821	}
1822
1823	int zd_usb_iowrite16v_async_end(struct zd_usb *usb, unsigned int timeout)
1824	{
1825	int r;
1826
1827	ZD_ASSERT(mutex_is_locked(&zd_usb_to_chip(usb)->mutex));
1828	ZD_ASSERT(usb->in_async);
1829
1830	/* Submit last iowrite16v URB */
1831	r = zd_submit_waiting_urb(usb, last: true);
1832	if (r) {
1833	dev_dbg_f(zd_usb_dev(usb),
1834	"error in zd_submit_waiting_usb(). "
1835	"Error number %d\n", r);
1836
1837	usb_kill_anchored_urbs(anchor: &usb->submitted_cmds);
1838	goto error;
1839	}
1840
1841	if (timeout)
1842	timeout = usb_wait_anchor_empty_timeout(anchor: &usb->submitted_cmds,
1843	timeout);
1844	if (!timeout) {
1845	usb_kill_anchored_urbs(anchor: &usb->submitted_cmds);
1846	if (usb->cmd_error == -ENOENT) {
1847	dev_dbg_f(zd_usb_dev(usb), "timed out");
1848	r = -ETIMEDOUT;
1849	goto error;
1850	}
1851	}
1852
1853	r = usb->cmd_error;
1854	error:
1855	usb->in_async = 0;
1856	return r;
1857	}
1858
1859	int zd_usb_iowrite16v_async(struct zd_usb *usb, const struct zd_ioreq16 *ioreqs,
1860	unsigned int count)
1861	{
1862	int r;
1863	struct usb_device *udev;
1864	struct usb_req_write_regs *req = NULL;
1865	int i, req_len;
1866	struct urb *urb;
1867	struct usb_host_endpoint *ep;
1868
1869	ZD_ASSERT(mutex_is_locked(&zd_usb_to_chip(usb)->mutex));
1870	ZD_ASSERT(usb->in_async);
1871
1872	if (count == 0)
1873	return 0;
1874	if (count > USB_MAX_IOWRITE16_COUNT) {
1875	dev_dbg_f(zd_usb_dev(usb),
1876	"error: count %u exceeds possible max %u\n",
1877	count, USB_MAX_IOWRITE16_COUNT);
1878	return -EINVAL;
1879	}
1880
1881	udev = zd_usb_to_usbdev(usb);
1882
1883	ep = usb_pipe_endpoint(dev: udev, usb_sndintpipe(udev, EP_REGS_OUT));
1884	if (!ep)
1885	return -ENOENT;
1886
1887	urb = usb_alloc_urb(iso_packets: 0, GFP_KERNEL);
1888	if (!urb)
1889	return -ENOMEM;
1890
1891	req_len = struct_size(req, reg_writes, count);
1892	req = kmalloc(size: req_len, GFP_KERNEL);
1893	if (!req) {
1894	r = -ENOMEM;
1895	goto error;
1896	}
1897
1898	req->id = cpu_to_le16(USB_REQ_WRITE_REGS);
1899	for (i = 0; i < count; i++) {
1900	struct reg_data *rw = &req->reg_writes[i];
1901	rw->addr = cpu_to_le16((u16)ioreqs[i].addr);
1902	rw->value = cpu_to_le16(ioreqs[i].value);
1903	}
1904
1905	/* In USB 2.0 mode endpoint is interrupt type. However in USB 1.1 mode
1906	* endpoint is bulk. Select correct type URB by endpoint descriptor.
1907	*/
1908	if (usb_endpoint_xfer_int(epd: &ep->desc))
1909	usb_fill_int_urb(urb, dev: udev, usb_sndintpipe(udev, EP_REGS_OUT),
1910	transfer_buffer: req, buffer_length: req_len, complete_fn: iowrite16v_urb_complete, context: usb,
1911	interval: ep->desc.bInterval);
1912	else
1913	usb_fill_bulk_urb(urb, dev: udev, usb_sndbulkpipe(udev, EP_REGS_OUT),
1914	transfer_buffer: req, buffer_length: req_len, complete_fn: iowrite16v_urb_complete, context: usb);
1915
1916	urb->transfer_flags |= URB_FREE_BUFFER;
1917
1918	/* Submit previous URB */
1919	r = zd_submit_waiting_urb(usb, last: false);
1920	if (r) {
1921	dev_dbg_f(zd_usb_dev(usb),
1922	"error in zd_submit_waiting_usb(). "
1923	"Error number %d\n", r);
1924	goto error;
1925	}
1926
1927	/* Delay submit so that URB_NO_INTERRUPT flag can be set for all URBs
1928	* of currect batch except for very last.
1929	*/
1930	usb->urb_async_waiting = urb;
1931	return 0;
1932	error:
1933	usb_free_urb(urb);
1934	return r;
1935	}
1936
1937	int zd_usb_iowrite16v(struct zd_usb *usb, const struct zd_ioreq16 *ioreqs,
1938	unsigned int count)
1939	{
1940	int r;
1941
1942	zd_usb_iowrite16v_async_start(usb);
1943	r = zd_usb_iowrite16v_async(usb, ioreqs, count);
1944	if (r) {
1945	zd_usb_iowrite16v_async_end(usb, timeout: 0);
1946	return r;
1947	}
1948	return zd_usb_iowrite16v_async_end(usb, timeout: 50 /* ms */);
1949	}
1950
1951	int zd_usb_rfwrite(struct zd_usb *usb, u32 value, u8 bits)
1952	{
1953	int r;
1954	struct usb_device *udev;
1955	struct usb_req_rfwrite *req = NULL;
1956	int i, req_len, actual_req_len;
1957	u16 bit_value_template;
1958
1959	if (bits < USB_MIN_RFWRITE_BIT_COUNT) {
1960	dev_dbg_f(zd_usb_dev(usb),
1961	"error: bits %d are smaller than"
1962	" USB_MIN_RFWRITE_BIT_COUNT %d\n",
1963	bits, USB_MIN_RFWRITE_BIT_COUNT);
1964	return -EINVAL;
1965	}
1966	if (bits > USB_MAX_RFWRITE_BIT_COUNT) {
1967	dev_dbg_f(zd_usb_dev(usb),
1968	"error: bits %d exceed USB_MAX_RFWRITE_BIT_COUNT %d\n",
1969	bits, USB_MAX_RFWRITE_BIT_COUNT);
1970	return -EINVAL;
1971	}
1972	#ifdef DEBUG
1973	if (value & (~0UL << bits)) {
1974	dev_dbg_f(zd_usb_dev(usb),
1975	"error: value %#09x has bits >= %d set\n",
1976	value, bits);
1977	return -EINVAL;
1978	}
1979	#endif /* DEBUG */
1980
1981	dev_dbg_f(zd_usb_dev(usb), "value %#09x bits %d\n", value, bits);
1982
1983	r = zd_usb_ioread16(usb, value: &bit_value_template, ZD_CR203);
1984	if (r) {
1985	dev_dbg_f(zd_usb_dev(usb),
1986	"error %d: Couldn't read ZD_CR203\n", r);
1987	return r;
1988	}
1989	bit_value_template &= ~(RF_IF_LE|RF_CLK|RF_DATA);
1990
1991	ZD_ASSERT(mutex_is_locked(&zd_usb_to_chip(usb)->mutex));
1992	BUILD_BUG_ON(sizeof(struct usb_req_rfwrite) +
1993	USB_MAX_RFWRITE_BIT_COUNT * sizeof(__le16) >
1994	sizeof(usb->req_buf));
1995	BUG_ON(sizeof(struct usb_req_rfwrite) + bits * sizeof(__le16) >
1996	sizeof(usb->req_buf));
1997
1998	req_len = sizeof(struct usb_req_rfwrite) + bits * sizeof(__le16);
1999	req = (void *)usb->req_buf;
2000
2001	req->id = cpu_to_le16(USB_REQ_WRITE_RF);
2002	/* 1: 3683a, but not used in ZYDAS driver */
2003	req->value = cpu_to_le16(2);
2004	req->bits = cpu_to_le16(bits);
2005
2006	for (i = 0; i < bits; i++) {
2007	u16 bv = bit_value_template;
2008	if (value & (1 << (bits-1-i)))
2009	bv |= RF_DATA;
2010	req->bit_values[i] = cpu_to_le16(bv);
2011	}
2012
2013	udev = zd_usb_to_usbdev(usb);
2014	r = zd_ep_regs_out_msg(udev, data: req, len: req_len, actual_length: &actual_req_len, timeout: 50 /*ms*/);
2015	if (r) {
2016	dev_dbg_f(zd_usb_dev(usb),
2017	"error in zd_ep_regs_out_msg(). Error number %d\n", r);
2018	goto out;
2019	}
2020	if (req_len != actual_req_len) {
2021	dev_dbg_f(zd_usb_dev(usb), "error in zd_ep_regs_out_msg()"
2022	" req_len %d != actual_req_len %d\n",
2023	req_len, actual_req_len);
2024	r = -EIO;
2025	goto out;
2026	}
2027
2028	/* FALL-THROUGH with r == 0 */
2029	out:
2030	return r;
2031	}
2032