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(0x07b8, 0x6001), .driver_info = DEVICE_ZD1211B },
69 	{ USB_DEVICE(0x07fa, 0x1196), .driver_info = DEVICE_ZD1211B },
70 	{ USB_DEVICE(0x083a, 0x4505), .driver_info = DEVICE_ZD1211B },
71 	{ USB_DEVICE(0x083a, 0xe501), .driver_info = DEVICE_ZD1211B },
72 	{ USB_DEVICE(0x083a, 0xe503), .driver_info = DEVICE_ZD1211B },
73 	{ USB_DEVICE(0x083a, 0xe506), .driver_info = DEVICE_ZD1211B },
74 	{ USB_DEVICE(0x0ace, 0x1215), .driver_info = DEVICE_ZD1211B },
75 	{ USB_DEVICE(0x0ace, 0xb215), .driver_info = DEVICE_ZD1211B },
76 	{ USB_DEVICE(0x0b05, 0x171b), .driver_info = DEVICE_ZD1211B },
77 	{ USB_DEVICE(0x0baf, 0x0121), .driver_info = DEVICE_ZD1211B },
78 	{ USB_DEVICE(0x0cde, 0x001a), .driver_info = DEVICE_ZD1211B },
79 	{ USB_DEVICE(0x0df6, 0x0036), .driver_info = DEVICE_ZD1211B },
80 	{ USB_DEVICE(0x129b, 0x1667), .driver_info = DEVICE_ZD1211B },
81 	{ USB_DEVICE(0x13b1, 0x0024), .driver_info = DEVICE_ZD1211B },
82 	{ USB_DEVICE(0x157e, 0x300d), .driver_info = DEVICE_ZD1211B },
83 	{ USB_DEVICE(0x1582, 0x6003), .driver_info = DEVICE_ZD1211B },
84 	{ USB_DEVICE(0x2019, 0x5303), .driver_info = DEVICE_ZD1211B },
85 	{ USB_DEVICE(0x2019, 0xed01), .driver_info = DEVICE_ZD1211B },
86 	/* "Driverless" devices that need ejecting */
87 	{ USB_DEVICE(0x0ace, 0x2011), .driver_info = DEVICE_INSTALLER },
88 	{ USB_DEVICE(0x0ace, 0x20ff), .driver_info = DEVICE_INSTALLER },
89 	{}
90 };
91 
92 MODULE_LICENSE("GPL");
93 MODULE_DESCRIPTION("USB driver for devices with the ZD1211 chip.");
94 MODULE_AUTHOR("Ulrich Kunitz");
95 MODULE_AUTHOR("Daniel Drake");
96 MODULE_VERSION("1.0");
97 MODULE_DEVICE_TABLE(usb, usb_ids);
98 
99 #define FW_ZD1211_PREFIX	"zd1211/zd1211_"
100 #define FW_ZD1211B_PREFIX	"zd1211/zd1211b_"
101 
102 static bool check_read_regs(struct zd_usb *usb, struct usb_req_read_regs *req,
103 			    unsigned int count);
104 
105 /* USB device initialization */
106 static void int_urb_complete(struct urb *urb);
107 
108 static int request_fw_file(
109 	const struct firmware **fw, const char *name, struct device *device)
110 {
111 	int r;
112 
113 	dev_dbg_f(device, "fw name %s\n", name);
114 
115 	r = request_firmware(fw, name, device);
116 	if (r)
117 		dev_err(device,
118 		       "Could not load firmware file %s. Error number %d\n",
119 		       name, r);
120 	return r;
121 }
122 
123 static inline u16 get_bcdDevice(const struct usb_device *udev)
124 {
125 	return le16_to_cpu(udev->descriptor.bcdDevice);
126 }
127 
128 enum upload_code_flags {
129 	REBOOT = 1,
130 };
131 
132 /* Ensures that MAX_TRANSFER_SIZE is even. */
133 #define MAX_TRANSFER_SIZE (USB_MAX_TRANSFER_SIZE & ~1)
134 
135 static int upload_code(struct usb_device *udev,
136 	const u8 *data, size_t size, u16 code_offset, int flags)
137 {
138 	u8 *p;
139 	int r;
140 
141 	/* USB request blocks need "kmalloced" buffers.
142 	 */
143 	p = kmalloc(MAX_TRANSFER_SIZE, GFP_KERNEL);
144 	if (!p) {
145 		r = -ENOMEM;
146 		goto error;
147 	}
148 
149 	size &= ~1;
150 	while (size > 0) {
151 		size_t transfer_size = size <= MAX_TRANSFER_SIZE ?
152 			size : MAX_TRANSFER_SIZE;
153 
154 		dev_dbg_f(&udev->dev, "transfer size %zu\n", transfer_size);
155 
156 		memcpy(p, data, transfer_size);
157 		r = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
158 			USB_REQ_FIRMWARE_DOWNLOAD,
159 			USB_DIR_OUT | USB_TYPE_VENDOR,
160 			code_offset, 0, p, transfer_size, 1000 /* ms */);
161 		if (r < 0) {
162 			dev_err(&udev->dev,
163 			       "USB control request for firmware upload"
164 			       " failed. Error number %d\n", r);
165 			goto error;
166 		}
167 		transfer_size = r & ~1;
168 
169 		size -= transfer_size;
170 		data += transfer_size;
171 		code_offset += transfer_size/sizeof(u16);
172 	}
173 
174 	if (flags & REBOOT) {
175 		u8 ret;
176 
177 		/* Use "DMA-aware" buffer. */
178 		r = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
179 			USB_REQ_FIRMWARE_CONFIRM,
180 			USB_DIR_IN | USB_TYPE_VENDOR,
181 			0, 0, p, sizeof(ret), 5000 /* ms */);
182 		if (r != sizeof(ret)) {
183 			dev_err(&udev->dev,
184 				"control request firmware confirmation failed."
185 				" Return value %d\n", r);
186 			if (r >= 0)
187 				r = -ENODEV;
188 			goto error;
189 		}
190 		ret = p[0];
191 		if (ret & 0x80) {
192 			dev_err(&udev->dev,
193 				"Internal error while downloading."
194 				" Firmware confirm return value %#04x\n",
195 				(unsigned int)ret);
196 			r = -ENODEV;
197 			goto error;
198 		}
199 		dev_dbg_f(&udev->dev, "firmware confirm return value %#04x\n",
200 			(unsigned int)ret);
201 	}
202 
203 	r = 0;
204 error:
205 	kfree(p);
206 	return r;
207 }
208 
209 static u16 get_word(const void *data, u16 offset)
210 {
211 	const __le16 *p = data;
212 	return le16_to_cpu(p[offset]);
213 }
214 
215 static char *get_fw_name(struct zd_usb *usb, char *buffer, size_t size,
216 	               const char* postfix)
217 {
218 	scnprintf(buffer, size, "%s%s",
219 		usb->is_zd1211b ?
220 			FW_ZD1211B_PREFIX : FW_ZD1211_PREFIX,
221 		postfix);
222 	return buffer;
223 }
224 
225 static int handle_version_mismatch(struct zd_usb *usb,
226 	const struct firmware *ub_fw)
227 {
228 	struct usb_device *udev = zd_usb_to_usbdev(usb);
229 	const struct firmware *ur_fw = NULL;
230 	int offset;
231 	int r = 0;
232 	char fw_name[128];
233 
234 	r = request_fw_file(&ur_fw,
235 		get_fw_name(usb, fw_name, sizeof(fw_name), "ur"),
236 		&udev->dev);
237 	if (r)
238 		goto error;
239 
240 	r = upload_code(udev, ur_fw->data, ur_fw->size, FW_START, REBOOT);
241 	if (r)
242 		goto error;
243 
244 	offset = (E2P_BOOT_CODE_OFFSET * sizeof(u16));
245 	r = upload_code(udev, ub_fw->data + offset, ub_fw->size - offset,
246 		E2P_START + E2P_BOOT_CODE_OFFSET, REBOOT);
247 
248 	/* At this point, the vendor driver downloads the whole firmware
249 	 * image, hacks around with version IDs, and uploads it again,
250 	 * completely overwriting the boot code. We do not do this here as
251 	 * it is not required on any tested devices, and it is suspected to
252 	 * cause problems. */
253 error:
254 	release_firmware(ur_fw);
255 	return r;
256 }
257 
258 static int upload_firmware(struct zd_usb *usb)
259 {
260 	int r;
261 	u16 fw_bcdDevice;
262 	u16 bcdDevice;
263 	struct usb_device *udev = zd_usb_to_usbdev(usb);
264 	const struct firmware *ub_fw = NULL;
265 	const struct firmware *uph_fw = NULL;
266 	char fw_name[128];
267 
268 	bcdDevice = get_bcdDevice(udev);
269 
270 	r = request_fw_file(&ub_fw,
271 		get_fw_name(usb, fw_name, sizeof(fw_name), "ub"),
272 		&udev->dev);
273 	if (r)
274 		goto error;
275 
276 	fw_bcdDevice = get_word(ub_fw->data, E2P_DATA_OFFSET);
277 
278 	if (fw_bcdDevice != bcdDevice) {
279 		dev_info(&udev->dev,
280 			"firmware version %#06x and device bootcode version "
281 			"%#06x differ\n", fw_bcdDevice, bcdDevice);
282 		if (bcdDevice <= 0x4313)
283 			dev_warn(&udev->dev, "device has old bootcode, please "
284 				"report success or failure\n");
285 
286 		r = handle_version_mismatch(usb, ub_fw);
287 		if (r)
288 			goto error;
289 	} else {
290 		dev_dbg_f(&udev->dev,
291 			"firmware device id %#06x is equal to the "
292 			"actual device id\n", fw_bcdDevice);
293 	}
294 
295 
296 	r = request_fw_file(&uph_fw,
297 		get_fw_name(usb, fw_name, sizeof(fw_name), "uphr"),
298 		&udev->dev);
299 	if (r)
300 		goto error;
301 
302 	r = upload_code(udev, uph_fw->data, uph_fw->size, FW_START, REBOOT);
303 	if (r) {
304 		dev_err(&udev->dev,
305 			"Could not upload firmware code uph. Error number %d\n",
306 			r);
307 	}
308 
309 	/* FALL-THROUGH */
310 error:
311 	release_firmware(ub_fw);
312 	release_firmware(uph_fw);
313 	return r;
314 }
315 
316 MODULE_FIRMWARE(FW_ZD1211B_PREFIX "ur");
317 MODULE_FIRMWARE(FW_ZD1211_PREFIX "ur");
318 MODULE_FIRMWARE(FW_ZD1211B_PREFIX "ub");
319 MODULE_FIRMWARE(FW_ZD1211_PREFIX "ub");
320 MODULE_FIRMWARE(FW_ZD1211B_PREFIX "uphr");
321 MODULE_FIRMWARE(FW_ZD1211_PREFIX "uphr");
322 
323 /* Read data from device address space using "firmware interface" which does
324  * not require firmware to be loaded. */
325 int zd_usb_read_fw(struct zd_usb *usb, zd_addr_t addr, u8 *data, u16 len)
326 {
327 	int r;
328 	struct usb_device *udev = zd_usb_to_usbdev(usb);
329 	u8 *buf;
330 
331 	/* Use "DMA-aware" buffer. */
332 	buf = kmalloc(len, GFP_KERNEL);
333 	if (!buf)
334 		return -ENOMEM;
335 	r = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
336 		USB_REQ_FIRMWARE_READ_DATA, USB_DIR_IN | 0x40, addr, 0,
337 		buf, len, 5000);
338 	if (r < 0) {
339 		dev_err(&udev->dev,
340 			"read over firmware interface failed: %d\n", r);
341 		goto exit;
342 	} else if (r != len) {
343 		dev_err(&udev->dev,
344 			"incomplete read over firmware interface: %d/%d\n",
345 			r, len);
346 		r = -EIO;
347 		goto exit;
348 	}
349 	r = 0;
350 	memcpy(data, buf, len);
351 exit:
352 	kfree(buf);
353 	return r;
354 }
355 
356 #define urb_dev(urb) (&(urb)->dev->dev)
357 
358 static inline void handle_regs_int_override(struct urb *urb)
359 {
360 	struct zd_usb *usb = urb->context;
361 	struct zd_usb_interrupt *intr = &usb->intr;
362 	unsigned long flags;
363 
364 	spin_lock_irqsave(&intr->lock, flags);
365 	if (atomic_read(&intr->read_regs_enabled)) {
366 		atomic_set(&intr->read_regs_enabled, 0);
367 		intr->read_regs_int_overridden = 1;
368 		complete(&intr->read_regs.completion);
369 	}
370 	spin_unlock_irqrestore(&intr->lock, flags);
371 }
372 
373 static inline void handle_regs_int(struct urb *urb)
374 {
375 	struct zd_usb *usb = urb->context;
376 	struct zd_usb_interrupt *intr = &usb->intr;
377 	unsigned long flags;
378 	int len;
379 	u16 int_num;
380 
381 	spin_lock_irqsave(&intr->lock, flags);
382 
383 	int_num = le16_to_cpu(*(__le16 *)(urb->transfer_buffer+2));
384 	if (int_num == CR_INTERRUPT) {
385 		struct zd_mac *mac = zd_hw_mac(zd_usb_to_hw(urb->context));
386 		spin_lock(&mac->lock);
387 		memcpy(&mac->intr_buffer, urb->transfer_buffer,
388 				USB_MAX_EP_INT_BUFFER);
389 		spin_unlock(&mac->lock);
390 		schedule_work(&mac->process_intr);
391 	} else if (atomic_read(&intr->read_regs_enabled)) {
392 		len = urb->actual_length;
393 		intr->read_regs.length = urb->actual_length;
394 		if (len > sizeof(intr->read_regs.buffer))
395 			len = sizeof(intr->read_regs.buffer);
396 
397 		memcpy(intr->read_regs.buffer, urb->transfer_buffer, len);
398 
399 		/* Sometimes USB_INT_ID_REGS is not overridden, but comes after
400 		 * USB_INT_ID_RETRY_FAILED. Read-reg retry then gets this
401 		 * delayed USB_INT_ID_REGS, but leaves USB_INT_ID_REGS of
402 		 * retry unhandled. Next read-reg command then might catch
403 		 * this wrong USB_INT_ID_REGS. Fix by ignoring wrong reads.
404 		 */
405 		if (!check_read_regs(usb, intr->read_regs.req,
406 						intr->read_regs.req_count))
407 			goto out;
408 
409 		atomic_set(&intr->read_regs_enabled, 0);
410 		intr->read_regs_int_overridden = 0;
411 		complete(&intr->read_regs.completion);
412 
413 		goto out;
414 	}
415 
416 out:
417 	spin_unlock_irqrestore(&intr->lock, flags);
418 
419 	/* CR_INTERRUPT might override read_reg too. */
420 	if (int_num == CR_INTERRUPT && atomic_read(&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(&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(&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(0, GFP_KERNEL);
524 	if (!urb) {
525 		r = -ENOMEM;
526 		goto out;
527 	}
528 
529 	ZD_ASSERT(!irqs_disabled());
530 	spin_lock_irq(&intr->lock);
531 	if (intr->urb) {
532 		spin_unlock_irq(&intr->lock);
533 		r = 0;
534 		goto error_free_urb;
535 	}
536 	intr->urb = urb;
537 	spin_unlock_irq(&intr->lock);
538 
539 	r = -ENOMEM;
540 	intr->buffer = usb_alloc_coherent(udev, USB_MAX_EP_INT_BUFFER,
541 					  GFP_KERNEL, &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, udev, usb_rcvintpipe(udev, EP_INT_IN),
549 			 intr->buffer, USB_MAX_EP_INT_BUFFER,
550 			 int_urb_complete, usb,
551 			 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(udev, USB_MAX_EP_INT_BUFFER,
566 			  intr->buffer, intr->buffer_dma);
567 error_set_urb_null:
568 	spin_lock_irq(&intr->lock);
569 	intr->urb = NULL;
570 	spin_unlock_irq(&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(&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(&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(udev, USB_MAX_EP_INT_BUFFER, buffer, 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(&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(&length_info->length[i]);
633 			if (k == 0)
634 				return;
635 			n = l+k;
636 			if (n > length)
637 				return;
638 			zd_mac_rx(zd_usb_to_hw(usb), buffer+l, k);
639 			if (i >= 2)
640 				return;
641 			l = (n+3) & ~3;
642 		}
643 	} else {
644 		zd_mac_rx(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(&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(&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, rx->fragment,
699 			         rx->fragment_length + length);
700 		rx->fragment_length = 0;
701 		spin_unlock_irqrestore(&rx->lock, flags);
702 	} else {
703 		spin_unlock_irqrestore(&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(0, GFP_KERNEL);
720 	if (!urb)
721 		return NULL;
722 	buffer = usb_alloc_coherent(udev, USB_MAX_RX_SIZE, GFP_KERNEL,
723 				    &urb->transfer_dma);
724 	if (!buffer) {
725 		usb_free_urb(urb);
726 		return NULL;
727 	}
728 
729 	usb_fill_bulk_urb(urb, udev, usb_rcvbulkpipe(udev, EP_DATA_IN),
730 			  buffer, USB_MAX_RX_SIZE,
731 			  rx_urb_complete, 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(urb->dev, urb->transfer_buffer_length,
742 			  urb->transfer_buffer, 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, 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(&rx->lock);
766 	if (rx->urbs) {
767 		spin_unlock_irq(&rx->lock);
768 		r = 0;
769 		goto error;
770 	}
771 	rx->urbs = urbs;
772 	rx->urbs_count = RX_URBS_COUNT;
773 	spin_unlock_irq(&rx->lock);
774 
775 	for (i = 0; i < RX_URBS_COUNT; i++) {
776 		r = usb_submit_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(urbs[i]);
785 	}
786 	spin_lock_irq(&rx->lock);
787 	rx->urbs = NULL;
788 	rx->urbs_count = 0;
789 	spin_unlock_irq(&rx->lock);
790 error:
791 	if (urbs) {
792 		for (i = 0; i < RX_URBS_COUNT; i++)
793 			free_rx_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(&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(&rx->lock, flags);
824 	if (!urbs)
825 		return;
826 
827 	for (i = 0; i < count; i++) {
828 		usb_kill_urb(urbs[i]);
829 		free_rx_urb(urbs[i]);
830 	}
831 	kfree(urbs);
832 
833 	spin_lock_irqsave(&rx->lock, flags);
834 	rx->urbs = NULL;
835 	rx->urbs_count = 0;
836 	spin_unlock_irqrestore(&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(&rx->setup_mutex);
846 
847 	tasklet_kill(&rx->reset_timer_tasklet);
848 	cancel_delayed_work_sync(&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(&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(&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(&tx->enabled, 0);
886 
887 	/* kill all submitted tx-urbs */
888 	usb_kill_anchored_urbs(&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(&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(&tx->enabled, 1);
915 	tx->submitted_urbs = 0;
916 	ieee80211_wake_queues(zd_usb_to_hw(usb));
917 	tx->stopped = 0;
918 	spin_unlock_irqrestore(&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(zd_usb_to_hw(usb));
930 		tx->stopped = 0;
931 	}
932 	spin_unlock_irqrestore(&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(zd_usb_to_hw(usb));
944 		tx->stopped = 1;
945 	}
946 	spin_unlock_irqrestore(&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(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, &usb->tx.submitted_skbs);
990 	zd_mac_tx_to_dev(skb, urb->status);
991 	usb_free_urb(urb);
992 	tx_dec_submitted_urbs(usb);
993 	return;
994 resubmit:
995 	usb_anchor_urb(urb, &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 tranmits 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(&tx->enabled)) {
1025 		r = -ENOENT;
1026 		goto out;
1027 	}
1028 
1029 	urb = usb_alloc_urb(0, GFP_ATOMIC);
1030 	if (!urb) {
1031 		r = -ENOMEM;
1032 		goto out;
1033 	}
1034 
1035 	usb_fill_bulk_urb(urb, udev, usb_sndbulkpipe(udev, EP_DATA_OUT),
1036 		          skb->data, skb->len, tx_urb_complete, skb);
1037 
1038 	info->rate_driver_data[1] = (void *)jiffies;
1039 	skb_queue_tail(&tx->submitted_skbs, skb);
1040 	usb_anchor_urb(urb, &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, &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(&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(&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(usb->intf);
1096 
1097 	/* reset will stop this worker, don't rearm */
1098 	return;
1099 out:
1100 	queue_delayed_work(zd_workqueue, &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(zd_workqueue, &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(&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(zd_workqueue, &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(zd_usb_to_usbdev(usb));
1162 	init_completion(&intr->read_regs.completion);
1163 	atomic_set(&intr->read_regs_enabled, 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(&tx->enabled, 0);
1191 	tx->stopped = 0;
1192 	skb_queue_head_init(&tx->submitted_skbs);
1193 	init_usb_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(usb->intf, hw);
1205 	init_usb_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(usb->intf, NULL);
1214 	usb_put_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(buffer, size, "%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(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, 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(endpoint) &&
1277 		    usb_endpoint_xfer_bulk(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(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(udev, usb_sndbulkpipe(udev, bulk_out_ep),
1304 		cmd, 31, NULL, 2000);
1305 	kfree(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(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(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(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(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(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(ZD_DEVICE_RUNNING, &mac->flags);
1461 		usb_queue_reset_device(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(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(&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(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(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(udev, pipe);
1585 	if (!ep)
1586 		return -EINVAL;
1587 
1588 	if (usb_endpoint_xfer_int(&ep->desc)) {
1589 		return usb_interrupt_msg(udev, pipe, data, len,
1590 					 actual_length, timeout);
1591 	} else {
1592 		pipe = usb_sndbulkpipe(udev, EP_REGS_OUT);
1593 		return usb_bulk_msg(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(&intr->lock);
1605 	atomic_set(&intr->read_regs_enabled, 1);
1606 	intr->read_regs.req = req;
1607 	intr->read_regs.req_count = count;
1608 	reinit_completion(&intr->read_regs.completion);
1609 	spin_unlock_irq(&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(&intr->lock);
1617 	atomic_set(&intr->read_regs_enabled, 0);
1618 	spin_unlock_irq(&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(&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(&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, req, req_len, &actual_req_len, 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(&usb->intr.read_regs.completion,
1752 					      msecs_to_jiffies(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);
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, &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, 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(&usb->submitted_cmds);
1838 		goto error;
1839 	}
1840 
1841 	if (timeout)
1842 		timeout = usb_wait_anchor_empty_timeout(&usb->submitted_cmds,
1843 							timeout);
1844 	if (!timeout) {
1845 		usb_kill_anchored_urbs(&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(udev, usb_sndintpipe(udev, EP_REGS_OUT));
1884 	if (!ep)
1885 		return -ENOENT;
1886 
1887 	urb = usb_alloc_urb(0, GFP_KERNEL);
1888 	if (!urb)
1889 		return -ENOMEM;
1890 
1891 	req_len = struct_size(req, reg_writes, count);
1892 	req = kmalloc(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(&ep->desc))
1909 		usb_fill_int_urb(urb, udev, usb_sndintpipe(udev, EP_REGS_OUT),
1910 				 req, req_len, iowrite16v_urb_complete, usb,
1911 				 ep->desc.bInterval);
1912 	else
1913 		usb_fill_bulk_urb(urb, udev, usb_sndbulkpipe(udev, EP_REGS_OUT),
1914 				  req, req_len, iowrite16v_urb_complete, usb);
1915 
1916 	urb->transfer_flags |= URB_FREE_BUFFER;
1917 
1918 	/* Submit previous URB */
1919 	r = zd_submit_waiting_urb(usb, 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, 0);
1946 		return r;
1947 	}
1948 	return zd_usb_iowrite16v_async_end(usb, 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, &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, req, req_len, &actual_req_len, 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