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