Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6
[linux-2.6.git] / drivers / net / wireless / zd1211rw / zd_usb.c
1 /* ZD1211 USB-WLAN driver for Linux
2  *
3  * Copyright (C) 2005-2007 Ulrich Kunitz <kune@deine-taler.de>
4  * Copyright (C) 2006-2007 Daniel Drake <dsd@gentoo.org>
5  * Copyright (C) 2006-2007 Michael Wu <flamingice@sourmilk.net>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20  */
21
22 #include <linux/kernel.h>
23 #include <linux/init.h>
24 #include <linux/firmware.h>
25 #include <linux/device.h>
26 #include <linux/errno.h>
27 #include <linux/slab.h>
28 #include <linux/skbuff.h>
29 #include <linux/usb.h>
30 #include <linux/workqueue.h>
31 #include <net/mac80211.h>
32 #include <asm/unaligned.h>
33
34 #include "zd_def.h"
35 #include "zd_mac.h"
36 #include "zd_usb.h"
37
38 static struct usb_device_id usb_ids[] = {
39         /* ZD1211 */
40         { USB_DEVICE(0x0105, 0x145f), .driver_info = DEVICE_ZD1211 },
41         { USB_DEVICE(0x0586, 0x3401), .driver_info = DEVICE_ZD1211 },
42         { USB_DEVICE(0x0586, 0x3402), .driver_info = DEVICE_ZD1211 },
43         { USB_DEVICE(0x0586, 0x3407), .driver_info = DEVICE_ZD1211 },
44         { USB_DEVICE(0x0586, 0x3409), .driver_info = DEVICE_ZD1211 },
45         { USB_DEVICE(0x079b, 0x004a), .driver_info = DEVICE_ZD1211 },
46         { USB_DEVICE(0x07b8, 0x6001), .driver_info = DEVICE_ZD1211 },
47         { USB_DEVICE(0x0ace, 0x1211), .driver_info = DEVICE_ZD1211 },
48         { USB_DEVICE(0x0ace, 0xa211), .driver_info = DEVICE_ZD1211 },
49         { USB_DEVICE(0x0b05, 0x170c), .driver_info = DEVICE_ZD1211 },
50         { USB_DEVICE(0x0b3b, 0x1630), .driver_info = DEVICE_ZD1211 },
51         { USB_DEVICE(0x0b3b, 0x5630), .driver_info = DEVICE_ZD1211 },
52         { USB_DEVICE(0x0df6, 0x9071), .driver_info = DEVICE_ZD1211 },
53         { USB_DEVICE(0x0df6, 0x9075), .driver_info = DEVICE_ZD1211 },
54         { USB_DEVICE(0x126f, 0xa006), .driver_info = DEVICE_ZD1211 },
55         { USB_DEVICE(0x129b, 0x1666), .driver_info = DEVICE_ZD1211 },
56         { USB_DEVICE(0x13b1, 0x001e), .driver_info = DEVICE_ZD1211 },
57         { USB_DEVICE(0x1435, 0x0711), .driver_info = DEVICE_ZD1211 },
58         { USB_DEVICE(0x14ea, 0xab10), .driver_info = DEVICE_ZD1211 },
59         { USB_DEVICE(0x14ea, 0xab13), .driver_info = DEVICE_ZD1211 },
60         { USB_DEVICE(0x157e, 0x300a), .driver_info = DEVICE_ZD1211 },
61         { USB_DEVICE(0x157e, 0x300b), .driver_info = DEVICE_ZD1211 },
62         { USB_DEVICE(0x157e, 0x3204), .driver_info = DEVICE_ZD1211 },
63         { USB_DEVICE(0x157e, 0x3207), .driver_info = DEVICE_ZD1211 },
64         { USB_DEVICE(0x1740, 0x2000), .driver_info = DEVICE_ZD1211 },
65         { USB_DEVICE(0x6891, 0xa727), .driver_info = DEVICE_ZD1211 },
66         /* ZD1211B */
67         { USB_DEVICE(0x0053, 0x5301), .driver_info = DEVICE_ZD1211B },
68         { USB_DEVICE(0x0409, 0x0248), .driver_info = DEVICE_ZD1211B },
69         { USB_DEVICE(0x0411, 0x00da), .driver_info = DEVICE_ZD1211B },
70         { USB_DEVICE(0x0471, 0x1236), .driver_info = DEVICE_ZD1211B },
71         { USB_DEVICE(0x0471, 0x1237), .driver_info = DEVICE_ZD1211B },
72         { USB_DEVICE(0x050d, 0x705c), .driver_info = DEVICE_ZD1211B },
73         { USB_DEVICE(0x054c, 0x0257), .driver_info = DEVICE_ZD1211B },
74         { USB_DEVICE(0x0586, 0x340a), .driver_info = DEVICE_ZD1211B },
75         { USB_DEVICE(0x0586, 0x340f), .driver_info = DEVICE_ZD1211B },
76         { USB_DEVICE(0x0586, 0x3410), .driver_info = DEVICE_ZD1211B },
77         { USB_DEVICE(0x0586, 0x3412), .driver_info = DEVICE_ZD1211B },
78         { USB_DEVICE(0x0586, 0x3413), .driver_info = DEVICE_ZD1211B },
79         { USB_DEVICE(0x079b, 0x0062), .driver_info = DEVICE_ZD1211B },
80         { USB_DEVICE(0x07b8, 0x6001), .driver_info = DEVICE_ZD1211B },
81         { USB_DEVICE(0x07fa, 0x1196), .driver_info = DEVICE_ZD1211B },
82         { USB_DEVICE(0x083a, 0x4505), .driver_info = DEVICE_ZD1211B },
83         { USB_DEVICE(0x083a, 0xe501), .driver_info = DEVICE_ZD1211B },
84         { USB_DEVICE(0x083a, 0xe503), .driver_info = DEVICE_ZD1211B },
85         { USB_DEVICE(0x083a, 0xe506), .driver_info = DEVICE_ZD1211B },
86         { USB_DEVICE(0x0ace, 0x1215), .driver_info = DEVICE_ZD1211B },
87         { USB_DEVICE(0x0ace, 0xb215), .driver_info = DEVICE_ZD1211B },
88         { USB_DEVICE(0x0b05, 0x171b), .driver_info = DEVICE_ZD1211B },
89         { USB_DEVICE(0x0baf, 0x0121), .driver_info = DEVICE_ZD1211B },
90         { USB_DEVICE(0x0cde, 0x001a), .driver_info = DEVICE_ZD1211B },
91         { USB_DEVICE(0x0df6, 0x0036), .driver_info = DEVICE_ZD1211B },
92         { USB_DEVICE(0x129b, 0x1667), .driver_info = DEVICE_ZD1211B },
93         { USB_DEVICE(0x13b1, 0x0024), .driver_info = DEVICE_ZD1211B },
94         { USB_DEVICE(0x157e, 0x300d), .driver_info = DEVICE_ZD1211B },
95         { USB_DEVICE(0x1582, 0x6003), .driver_info = DEVICE_ZD1211B },
96         { USB_DEVICE(0x2019, 0x5303), .driver_info = DEVICE_ZD1211B },
97         { USB_DEVICE(0x2019, 0xed01), .driver_info = DEVICE_ZD1211B },
98         /* "Driverless" devices that need ejecting */
99         { USB_DEVICE(0x0ace, 0x2011), .driver_info = DEVICE_INSTALLER },
100         { USB_DEVICE(0x0ace, 0x20ff), .driver_info = DEVICE_INSTALLER },
101         {}
102 };
103
104 MODULE_LICENSE("GPL");
105 MODULE_DESCRIPTION("USB driver for devices with the ZD1211 chip.");
106 MODULE_AUTHOR("Ulrich Kunitz");
107 MODULE_AUTHOR("Daniel Drake");
108 MODULE_VERSION("1.0");
109 MODULE_DEVICE_TABLE(usb, usb_ids);
110
111 #define FW_ZD1211_PREFIX        "zd1211/zd1211_"
112 #define FW_ZD1211B_PREFIX       "zd1211/zd1211b_"
113
114 /* USB device initialization */
115 static void int_urb_complete(struct urb *urb);
116
117 static int request_fw_file(
118         const struct firmware **fw, const char *name, struct device *device)
119 {
120         int r;
121
122         dev_dbg_f(device, "fw name %s\n", name);
123
124         r = request_firmware(fw, name, device);
125         if (r)
126                 dev_err(device,
127                        "Could not load firmware file %s. Error number %d\n",
128                        name, r);
129         return r;
130 }
131
132 static inline u16 get_bcdDevice(const struct usb_device *udev)
133 {
134         return le16_to_cpu(udev->descriptor.bcdDevice);
135 }
136
137 enum upload_code_flags {
138         REBOOT = 1,
139 };
140
141 /* Ensures that MAX_TRANSFER_SIZE is even. */
142 #define MAX_TRANSFER_SIZE (USB_MAX_TRANSFER_SIZE & ~1)
143
144 static int upload_code(struct usb_device *udev,
145         const u8 *data, size_t size, u16 code_offset, int flags)
146 {
147         u8 *p;
148         int r;
149
150         /* USB request blocks need "kmalloced" buffers.
151          */
152         p = kmalloc(MAX_TRANSFER_SIZE, GFP_KERNEL);
153         if (!p) {
154                 dev_err(&udev->dev, "out of memory\n");
155                 r = -ENOMEM;
156                 goto error;
157         }
158
159         size &= ~1;
160         while (size > 0) {
161                 size_t transfer_size = size <= MAX_TRANSFER_SIZE ?
162                         size : MAX_TRANSFER_SIZE;
163
164                 dev_dbg_f(&udev->dev, "transfer size %zu\n", transfer_size);
165
166                 memcpy(p, data, transfer_size);
167                 r = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
168                         USB_REQ_FIRMWARE_DOWNLOAD,
169                         USB_DIR_OUT | USB_TYPE_VENDOR,
170                         code_offset, 0, p, transfer_size, 1000 /* ms */);
171                 if (r < 0) {
172                         dev_err(&udev->dev,
173                                "USB control request for firmware upload"
174                                " failed. Error number %d\n", r);
175                         goto error;
176                 }
177                 transfer_size = r & ~1;
178
179                 size -= transfer_size;
180                 data += transfer_size;
181                 code_offset += transfer_size/sizeof(u16);
182         }
183
184         if (flags & REBOOT) {
185                 u8 ret;
186
187                 /* Use "DMA-aware" buffer. */
188                 r = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
189                         USB_REQ_FIRMWARE_CONFIRM,
190                         USB_DIR_IN | USB_TYPE_VENDOR,
191                         0, 0, p, sizeof(ret), 5000 /* ms */);
192                 if (r != sizeof(ret)) {
193                         dev_err(&udev->dev,
194                                 "control request firmeware confirmation failed."
195                                 " Return value %d\n", r);
196                         if (r >= 0)
197                                 r = -ENODEV;
198                         goto error;
199                 }
200                 ret = p[0];
201                 if (ret & 0x80) {
202                         dev_err(&udev->dev,
203                                 "Internal error while downloading."
204                                 " Firmware confirm return value %#04x\n",
205                                 (unsigned int)ret);
206                         r = -ENODEV;
207                         goto error;
208                 }
209                 dev_dbg_f(&udev->dev, "firmware confirm return value %#04x\n",
210                         (unsigned int)ret);
211         }
212
213         r = 0;
214 error:
215         kfree(p);
216         return r;
217 }
218
219 static u16 get_word(const void *data, u16 offset)
220 {
221         const __le16 *p = data;
222         return le16_to_cpu(p[offset]);
223 }
224
225 static char *get_fw_name(struct zd_usb *usb, char *buffer, size_t size,
226                        const char* postfix)
227 {
228         scnprintf(buffer, size, "%s%s",
229                 usb->is_zd1211b ?
230                         FW_ZD1211B_PREFIX : FW_ZD1211_PREFIX,
231                 postfix);
232         return buffer;
233 }
234
235 static int handle_version_mismatch(struct zd_usb *usb,
236         const struct firmware *ub_fw)
237 {
238         struct usb_device *udev = zd_usb_to_usbdev(usb);
239         const struct firmware *ur_fw = NULL;
240         int offset;
241         int r = 0;
242         char fw_name[128];
243
244         r = request_fw_file(&ur_fw,
245                 get_fw_name(usb, fw_name, sizeof(fw_name), "ur"),
246                 &udev->dev);
247         if (r)
248                 goto error;
249
250         r = upload_code(udev, ur_fw->data, ur_fw->size, FW_START, REBOOT);
251         if (r)
252                 goto error;
253
254         offset = (E2P_BOOT_CODE_OFFSET * sizeof(u16));
255         r = upload_code(udev, ub_fw->data + offset, ub_fw->size - offset,
256                 E2P_START + E2P_BOOT_CODE_OFFSET, REBOOT);
257
258         /* At this point, the vendor driver downloads the whole firmware
259          * image, hacks around with version IDs, and uploads it again,
260          * completely overwriting the boot code. We do not do this here as
261          * it is not required on any tested devices, and it is suspected to
262          * cause problems. */
263 error:
264         release_firmware(ur_fw);
265         return r;
266 }
267
268 static int upload_firmware(struct zd_usb *usb)
269 {
270         int r;
271         u16 fw_bcdDevice;
272         u16 bcdDevice;
273         struct usb_device *udev = zd_usb_to_usbdev(usb);
274         const struct firmware *ub_fw = NULL;
275         const struct firmware *uph_fw = NULL;
276         char fw_name[128];
277
278         bcdDevice = get_bcdDevice(udev);
279
280         r = request_fw_file(&ub_fw,
281                 get_fw_name(usb, fw_name, sizeof(fw_name), "ub"),
282                 &udev->dev);
283         if (r)
284                 goto error;
285
286         fw_bcdDevice = get_word(ub_fw->data, E2P_DATA_OFFSET);
287
288         if (fw_bcdDevice != bcdDevice) {
289                 dev_info(&udev->dev,
290                         "firmware version %#06x and device bootcode version "
291                         "%#06x differ\n", fw_bcdDevice, bcdDevice);
292                 if (bcdDevice <= 0x4313)
293                         dev_warn(&udev->dev, "device has old bootcode, please "
294                                 "report success or failure\n");
295
296                 r = handle_version_mismatch(usb, ub_fw);
297                 if (r)
298                         goto error;
299         } else {
300                 dev_dbg_f(&udev->dev,
301                         "firmware device id %#06x is equal to the "
302                         "actual device id\n", fw_bcdDevice);
303         }
304
305
306         r = request_fw_file(&uph_fw,
307                 get_fw_name(usb, fw_name, sizeof(fw_name), "uphr"),
308                 &udev->dev);
309         if (r)
310                 goto error;
311
312         r = upload_code(udev, uph_fw->data, uph_fw->size, FW_START, REBOOT);
313         if (r) {
314                 dev_err(&udev->dev,
315                         "Could not upload firmware code uph. Error number %d\n",
316                         r);
317         }
318
319         /* FALL-THROUGH */
320 error:
321         release_firmware(ub_fw);
322         release_firmware(uph_fw);
323         return r;
324 }
325
326 MODULE_FIRMWARE(FW_ZD1211B_PREFIX "ur");
327 MODULE_FIRMWARE(FW_ZD1211_PREFIX "ur");
328 MODULE_FIRMWARE(FW_ZD1211B_PREFIX "ub");
329 MODULE_FIRMWARE(FW_ZD1211_PREFIX "ub");
330 MODULE_FIRMWARE(FW_ZD1211B_PREFIX "uphr");
331 MODULE_FIRMWARE(FW_ZD1211_PREFIX "uphr");
332
333 /* Read data from device address space using "firmware interface" which does
334  * not require firmware to be loaded. */
335 int zd_usb_read_fw(struct zd_usb *usb, zd_addr_t addr, u8 *data, u16 len)
336 {
337         int r;
338         struct usb_device *udev = zd_usb_to_usbdev(usb);
339         u8 *buf;
340
341         /* Use "DMA-aware" buffer. */
342         buf = kmalloc(len, GFP_KERNEL);
343         if (!buf)
344                 return -ENOMEM;
345         r = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
346                 USB_REQ_FIRMWARE_READ_DATA, USB_DIR_IN | 0x40, addr, 0,
347                 buf, len, 5000);
348         if (r < 0) {
349                 dev_err(&udev->dev,
350                         "read over firmware interface failed: %d\n", r);
351                 goto exit;
352         } else if (r != len) {
353                 dev_err(&udev->dev,
354                         "incomplete read over firmware interface: %d/%d\n",
355                         r, len);
356                 r = -EIO;
357                 goto exit;
358         }
359         r = 0;
360         memcpy(data, buf, len);
361 exit:
362         kfree(buf);
363         return r;
364 }
365
366 #define urb_dev(urb) (&(urb)->dev->dev)
367
368 static inline void handle_regs_int(struct urb *urb)
369 {
370         struct zd_usb *usb = urb->context;
371         struct zd_usb_interrupt *intr = &usb->intr;
372         int len;
373         u16 int_num;
374
375         ZD_ASSERT(in_interrupt());
376         spin_lock(&intr->lock);
377
378         int_num = le16_to_cpu(*(__le16 *)(urb->transfer_buffer+2));
379         if (int_num == CR_INTERRUPT) {
380                 struct zd_mac *mac = zd_hw_mac(zd_usb_to_hw(urb->context));
381                 spin_lock(&mac->lock);
382                 memcpy(&mac->intr_buffer, urb->transfer_buffer,
383                                 USB_MAX_EP_INT_BUFFER);
384                 spin_unlock(&mac->lock);
385                 schedule_work(&mac->process_intr);
386         } else if (intr->read_regs_enabled) {
387                 intr->read_regs.length = len = urb->actual_length;
388
389                 if (len > sizeof(intr->read_regs.buffer))
390                         len = sizeof(intr->read_regs.buffer);
391                 memcpy(intr->read_regs.buffer, urb->transfer_buffer, len);
392                 intr->read_regs_enabled = 0;
393                 complete(&intr->read_regs.completion);
394                 goto out;
395         }
396
397 out:
398         spin_unlock(&intr->lock);
399 }
400
401 static void int_urb_complete(struct urb *urb)
402 {
403         int r;
404         struct usb_int_header *hdr;
405
406         switch (urb->status) {
407         case 0:
408                 break;
409         case -ESHUTDOWN:
410         case -EINVAL:
411         case -ENODEV:
412         case -ENOENT:
413         case -ECONNRESET:
414         case -EPIPE:
415                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
416                 return;
417         default:
418                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
419                 goto resubmit;
420         }
421
422         if (urb->actual_length < sizeof(hdr)) {
423                 dev_dbg_f(urb_dev(urb), "error: urb %p to small\n", urb);
424                 goto resubmit;
425         }
426
427         hdr = urb->transfer_buffer;
428         if (hdr->type != USB_INT_TYPE) {
429                 dev_dbg_f(urb_dev(urb), "error: urb %p wrong type\n", urb);
430                 goto resubmit;
431         }
432
433         switch (hdr->id) {
434         case USB_INT_ID_REGS:
435                 handle_regs_int(urb);
436                 break;
437         case USB_INT_ID_RETRY_FAILED:
438                 zd_mac_tx_failed(urb);
439                 break;
440         default:
441                 dev_dbg_f(urb_dev(urb), "error: urb %p unknown id %x\n", urb,
442                         (unsigned int)hdr->id);
443                 goto resubmit;
444         }
445
446 resubmit:
447         r = usb_submit_urb(urb, GFP_ATOMIC);
448         if (r) {
449                 dev_dbg_f(urb_dev(urb), "error: resubmit urb %p err code %d\n",
450                           urb, r);
451                 /* TODO: add worker to reset intr->urb */
452         }
453         return;
454 }
455
456 static inline int int_urb_interval(struct usb_device *udev)
457 {
458         switch (udev->speed) {
459         case USB_SPEED_HIGH:
460                 return 4;
461         case USB_SPEED_LOW:
462                 return 10;
463         case USB_SPEED_FULL:
464         default:
465                 return 1;
466         }
467 }
468
469 static inline int usb_int_enabled(struct zd_usb *usb)
470 {
471         unsigned long flags;
472         struct zd_usb_interrupt *intr = &usb->intr;
473         struct urb *urb;
474
475         spin_lock_irqsave(&intr->lock, flags);
476         urb = intr->urb;
477         spin_unlock_irqrestore(&intr->lock, flags);
478         return urb != NULL;
479 }
480
481 int zd_usb_enable_int(struct zd_usb *usb)
482 {
483         int r;
484         struct usb_device *udev = zd_usb_to_usbdev(usb);
485         struct zd_usb_interrupt *intr = &usb->intr;
486         struct urb *urb;
487
488         dev_dbg_f(zd_usb_dev(usb), "\n");
489
490         urb = usb_alloc_urb(0, GFP_KERNEL);
491         if (!urb) {
492                 r = -ENOMEM;
493                 goto out;
494         }
495
496         ZD_ASSERT(!irqs_disabled());
497         spin_lock_irq(&intr->lock);
498         if (intr->urb) {
499                 spin_unlock_irq(&intr->lock);
500                 r = 0;
501                 goto error_free_urb;
502         }
503         intr->urb = urb;
504         spin_unlock_irq(&intr->lock);
505
506         r = -ENOMEM;
507         intr->buffer = usb_alloc_coherent(udev, USB_MAX_EP_INT_BUFFER,
508                                           GFP_KERNEL, &intr->buffer_dma);
509         if (!intr->buffer) {
510                 dev_dbg_f(zd_usb_dev(usb),
511                         "couldn't allocate transfer_buffer\n");
512                 goto error_set_urb_null;
513         }
514
515         usb_fill_int_urb(urb, udev, usb_rcvintpipe(udev, EP_INT_IN),
516                          intr->buffer, USB_MAX_EP_INT_BUFFER,
517                          int_urb_complete, usb,
518                          intr->interval);
519         urb->transfer_dma = intr->buffer_dma;
520         urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
521
522         dev_dbg_f(zd_usb_dev(usb), "submit urb %p\n", intr->urb);
523         r = usb_submit_urb(urb, GFP_KERNEL);
524         if (r) {
525                 dev_dbg_f(zd_usb_dev(usb),
526                          "Couldn't submit urb. Error number %d\n", r);
527                 goto error;
528         }
529
530         return 0;
531 error:
532         usb_free_coherent(udev, USB_MAX_EP_INT_BUFFER,
533                           intr->buffer, intr->buffer_dma);
534 error_set_urb_null:
535         spin_lock_irq(&intr->lock);
536         intr->urb = NULL;
537         spin_unlock_irq(&intr->lock);
538 error_free_urb:
539         usb_free_urb(urb);
540 out:
541         return r;
542 }
543
544 void zd_usb_disable_int(struct zd_usb *usb)
545 {
546         unsigned long flags;
547         struct usb_device *udev = zd_usb_to_usbdev(usb);
548         struct zd_usb_interrupt *intr = &usb->intr;
549         struct urb *urb;
550         void *buffer;
551         dma_addr_t buffer_dma;
552
553         spin_lock_irqsave(&intr->lock, flags);
554         urb = intr->urb;
555         if (!urb) {
556                 spin_unlock_irqrestore(&intr->lock, flags);
557                 return;
558         }
559         intr->urb = NULL;
560         buffer = intr->buffer;
561         buffer_dma = intr->buffer_dma;
562         intr->buffer = NULL;
563         spin_unlock_irqrestore(&intr->lock, flags);
564
565         usb_kill_urb(urb);
566         dev_dbg_f(zd_usb_dev(usb), "urb %p killed\n", urb);
567         usb_free_urb(urb);
568
569         if (buffer)
570                 usb_free_coherent(udev, USB_MAX_EP_INT_BUFFER,
571                                   buffer, buffer_dma);
572 }
573
574 static void handle_rx_packet(struct zd_usb *usb, const u8 *buffer,
575                              unsigned int length)
576 {
577         int i;
578         const struct rx_length_info *length_info;
579
580         if (length < sizeof(struct rx_length_info)) {
581                 /* It's not a complete packet anyhow. */
582                 printk("%s: invalid, small RX packet : %d\n",
583                        __func__, length);
584                 return;
585         }
586         length_info = (struct rx_length_info *)
587                 (buffer + length - sizeof(struct rx_length_info));
588
589         /* It might be that three frames are merged into a single URB
590          * transaction. We have to check for the length info tag.
591          *
592          * While testing we discovered that length_info might be unaligned,
593          * because if USB transactions are merged, the last packet will not
594          * be padded. Unaligned access might also happen if the length_info
595          * structure is not present.
596          */
597         if (get_unaligned_le16(&length_info->tag) == RX_LENGTH_INFO_TAG)
598         {
599                 unsigned int l, k, n;
600                 for (i = 0, l = 0;; i++) {
601                         k = get_unaligned_le16(&length_info->length[i]);
602                         if (k == 0)
603                                 return;
604                         n = l+k;
605                         if (n > length)
606                                 return;
607                         zd_mac_rx(zd_usb_to_hw(usb), buffer+l, k);
608                         if (i >= 2)
609                                 return;
610                         l = (n+3) & ~3;
611                 }
612         } else {
613                 zd_mac_rx(zd_usb_to_hw(usb), buffer, length);
614         }
615 }
616
617 static void rx_urb_complete(struct urb *urb)
618 {
619         int r;
620         struct zd_usb *usb;
621         struct zd_usb_rx *rx;
622         const u8 *buffer;
623         unsigned int length;
624
625         switch (urb->status) {
626         case 0:
627                 break;
628         case -ESHUTDOWN:
629         case -EINVAL:
630         case -ENODEV:
631         case -ENOENT:
632         case -ECONNRESET:
633         case -EPIPE:
634                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
635                 return;
636         default:
637                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
638                 goto resubmit;
639         }
640
641         buffer = urb->transfer_buffer;
642         length = urb->actual_length;
643         usb = urb->context;
644         rx = &usb->rx;
645
646         tasklet_schedule(&rx->reset_timer_tasklet);
647
648         if (length%rx->usb_packet_size > rx->usb_packet_size-4) {
649                 /* If there is an old first fragment, we don't care. */
650                 dev_dbg_f(urb_dev(urb), "*** first fragment ***\n");
651                 ZD_ASSERT(length <= ARRAY_SIZE(rx->fragment));
652                 spin_lock(&rx->lock);
653                 memcpy(rx->fragment, buffer, length);
654                 rx->fragment_length = length;
655                 spin_unlock(&rx->lock);
656                 goto resubmit;
657         }
658
659         spin_lock(&rx->lock);
660         if (rx->fragment_length > 0) {
661                 /* We are on a second fragment, we believe */
662                 ZD_ASSERT(length + rx->fragment_length <=
663                           ARRAY_SIZE(rx->fragment));
664                 dev_dbg_f(urb_dev(urb), "*** second fragment ***\n");
665                 memcpy(rx->fragment+rx->fragment_length, buffer, length);
666                 handle_rx_packet(usb, rx->fragment,
667                                  rx->fragment_length + length);
668                 rx->fragment_length = 0;
669                 spin_unlock(&rx->lock);
670         } else {
671                 spin_unlock(&rx->lock);
672                 handle_rx_packet(usb, buffer, length);
673         }
674
675 resubmit:
676         r = usb_submit_urb(urb, GFP_ATOMIC);
677         if (r)
678                 dev_dbg_f(urb_dev(urb), "urb %p resubmit error %d\n", urb, r);
679 }
680
681 static struct urb *alloc_rx_urb(struct zd_usb *usb)
682 {
683         struct usb_device *udev = zd_usb_to_usbdev(usb);
684         struct urb *urb;
685         void *buffer;
686
687         urb = usb_alloc_urb(0, GFP_KERNEL);
688         if (!urb)
689                 return NULL;
690         buffer = usb_alloc_coherent(udev, USB_MAX_RX_SIZE, GFP_KERNEL,
691                                     &urb->transfer_dma);
692         if (!buffer) {
693                 usb_free_urb(urb);
694                 return NULL;
695         }
696
697         usb_fill_bulk_urb(urb, udev, usb_rcvbulkpipe(udev, EP_DATA_IN),
698                           buffer, USB_MAX_RX_SIZE,
699                           rx_urb_complete, usb);
700         urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
701
702         return urb;
703 }
704
705 static void free_rx_urb(struct urb *urb)
706 {
707         if (!urb)
708                 return;
709         usb_free_coherent(urb->dev, urb->transfer_buffer_length,
710                           urb->transfer_buffer, urb->transfer_dma);
711         usb_free_urb(urb);
712 }
713
714 static int __zd_usb_enable_rx(struct zd_usb *usb)
715 {
716         int i, r;
717         struct zd_usb_rx *rx = &usb->rx;
718         struct urb **urbs;
719
720         dev_dbg_f(zd_usb_dev(usb), "\n");
721
722         r = -ENOMEM;
723         urbs = kcalloc(RX_URBS_COUNT, sizeof(struct urb *), GFP_KERNEL);
724         if (!urbs)
725                 goto error;
726         for (i = 0; i < RX_URBS_COUNT; i++) {
727                 urbs[i] = alloc_rx_urb(usb);
728                 if (!urbs[i])
729                         goto error;
730         }
731
732         ZD_ASSERT(!irqs_disabled());
733         spin_lock_irq(&rx->lock);
734         if (rx->urbs) {
735                 spin_unlock_irq(&rx->lock);
736                 r = 0;
737                 goto error;
738         }
739         rx->urbs = urbs;
740         rx->urbs_count = RX_URBS_COUNT;
741         spin_unlock_irq(&rx->lock);
742
743         for (i = 0; i < RX_URBS_COUNT; i++) {
744                 r = usb_submit_urb(urbs[i], GFP_KERNEL);
745                 if (r)
746                         goto error_submit;
747         }
748
749         return 0;
750 error_submit:
751         for (i = 0; i < RX_URBS_COUNT; i++) {
752                 usb_kill_urb(urbs[i]);
753         }
754         spin_lock_irq(&rx->lock);
755         rx->urbs = NULL;
756         rx->urbs_count = 0;
757         spin_unlock_irq(&rx->lock);
758 error:
759         if (urbs) {
760                 for (i = 0; i < RX_URBS_COUNT; i++)
761                         free_rx_urb(urbs[i]);
762         }
763         return r;
764 }
765
766 int zd_usb_enable_rx(struct zd_usb *usb)
767 {
768         int r;
769         struct zd_usb_rx *rx = &usb->rx;
770
771         mutex_lock(&rx->setup_mutex);
772         r = __zd_usb_enable_rx(usb);
773         mutex_unlock(&rx->setup_mutex);
774
775         zd_usb_reset_rx_idle_timer(usb);
776
777         return r;
778 }
779
780 static void __zd_usb_disable_rx(struct zd_usb *usb)
781 {
782         int i;
783         unsigned long flags;
784         struct urb **urbs;
785         unsigned int count;
786         struct zd_usb_rx *rx = &usb->rx;
787
788         spin_lock_irqsave(&rx->lock, flags);
789         urbs = rx->urbs;
790         count = rx->urbs_count;
791         spin_unlock_irqrestore(&rx->lock, flags);
792         if (!urbs)
793                 return;
794
795         for (i = 0; i < count; i++) {
796                 usb_kill_urb(urbs[i]);
797                 free_rx_urb(urbs[i]);
798         }
799         kfree(urbs);
800
801         spin_lock_irqsave(&rx->lock, flags);
802         rx->urbs = NULL;
803         rx->urbs_count = 0;
804         spin_unlock_irqrestore(&rx->lock, flags);
805 }
806
807 void zd_usb_disable_rx(struct zd_usb *usb)
808 {
809         struct zd_usb_rx *rx = &usb->rx;
810
811         mutex_lock(&rx->setup_mutex);
812         __zd_usb_disable_rx(usb);
813         mutex_unlock(&rx->setup_mutex);
814
815         tasklet_kill(&rx->reset_timer_tasklet);
816         cancel_delayed_work_sync(&rx->idle_work);
817 }
818
819 static void zd_usb_reset_rx(struct zd_usb *usb)
820 {
821         bool do_reset;
822         struct zd_usb_rx *rx = &usb->rx;
823         unsigned long flags;
824
825         mutex_lock(&rx->setup_mutex);
826
827         spin_lock_irqsave(&rx->lock, flags);
828         do_reset = rx->urbs != NULL;
829         spin_unlock_irqrestore(&rx->lock, flags);
830
831         if (do_reset) {
832                 __zd_usb_disable_rx(usb);
833                 __zd_usb_enable_rx(usb);
834         }
835
836         mutex_unlock(&rx->setup_mutex);
837
838         if (do_reset)
839                 zd_usb_reset_rx_idle_timer(usb);
840 }
841
842 /**
843  * zd_usb_disable_tx - disable transmission
844  * @usb: the zd1211rw-private USB structure
845  *
846  * Frees all URBs in the free list and marks the transmission as disabled.
847  */
848 void zd_usb_disable_tx(struct zd_usb *usb)
849 {
850         struct zd_usb_tx *tx = &usb->tx;
851         unsigned long flags;
852
853         atomic_set(&tx->enabled, 0);
854
855         /* kill all submitted tx-urbs */
856         usb_kill_anchored_urbs(&tx->submitted);
857
858         spin_lock_irqsave(&tx->lock, flags);
859         WARN_ON(!skb_queue_empty(&tx->submitted_skbs));
860         WARN_ON(tx->submitted_urbs != 0);
861         tx->submitted_urbs = 0;
862         spin_unlock_irqrestore(&tx->lock, flags);
863
864         /* The stopped state is ignored, relying on ieee80211_wake_queues()
865          * in a potentionally following zd_usb_enable_tx().
866          */
867 }
868
869 /**
870  * zd_usb_enable_tx - enables transmission
871  * @usb: a &struct zd_usb pointer
872  *
873  * This function enables transmission and prepares the &zd_usb_tx data
874  * structure.
875  */
876 void zd_usb_enable_tx(struct zd_usb *usb)
877 {
878         unsigned long flags;
879         struct zd_usb_tx *tx = &usb->tx;
880
881         spin_lock_irqsave(&tx->lock, flags);
882         atomic_set(&tx->enabled, 1);
883         tx->submitted_urbs = 0;
884         ieee80211_wake_queues(zd_usb_to_hw(usb));
885         tx->stopped = 0;
886         spin_unlock_irqrestore(&tx->lock, flags);
887 }
888
889 static void tx_dec_submitted_urbs(struct zd_usb *usb)
890 {
891         struct zd_usb_tx *tx = &usb->tx;
892         unsigned long flags;
893
894         spin_lock_irqsave(&tx->lock, flags);
895         --tx->submitted_urbs;
896         if (tx->stopped && tx->submitted_urbs <= ZD_USB_TX_LOW) {
897                 ieee80211_wake_queues(zd_usb_to_hw(usb));
898                 tx->stopped = 0;
899         }
900         spin_unlock_irqrestore(&tx->lock, flags);
901 }
902
903 static void tx_inc_submitted_urbs(struct zd_usb *usb)
904 {
905         struct zd_usb_tx *tx = &usb->tx;
906         unsigned long flags;
907
908         spin_lock_irqsave(&tx->lock, flags);
909         ++tx->submitted_urbs;
910         if (!tx->stopped && tx->submitted_urbs > ZD_USB_TX_HIGH) {
911                 ieee80211_stop_queues(zd_usb_to_hw(usb));
912                 tx->stopped = 1;
913         }
914         spin_unlock_irqrestore(&tx->lock, flags);
915 }
916
917 /**
918  * tx_urb_complete - completes the execution of an URB
919  * @urb: a URB
920  *
921  * This function is called if the URB has been transferred to a device or an
922  * error has happened.
923  */
924 static void tx_urb_complete(struct urb *urb)
925 {
926         int r;
927         struct sk_buff *skb;
928         struct ieee80211_tx_info *info;
929         struct zd_usb *usb;
930         struct zd_usb_tx *tx;
931
932         skb = (struct sk_buff *)urb->context;
933         info = IEEE80211_SKB_CB(skb);
934         /*
935          * grab 'usb' pointer before handing off the skb (since
936          * it might be freed by zd_mac_tx_to_dev or mac80211)
937          */
938         usb = &zd_hw_mac(info->rate_driver_data[0])->chip.usb;
939         tx = &usb->tx;
940
941         switch (urb->status) {
942         case 0:
943                 break;
944         case -ESHUTDOWN:
945         case -EINVAL:
946         case -ENODEV:
947         case -ENOENT:
948         case -ECONNRESET:
949         case -EPIPE:
950                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
951                 break;
952         default:
953                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
954                 goto resubmit;
955         }
956 free_urb:
957         skb_unlink(skb, &usb->tx.submitted_skbs);
958         zd_mac_tx_to_dev(skb, urb->status);
959         usb_free_urb(urb);
960         tx_dec_submitted_urbs(usb);
961         return;
962 resubmit:
963         usb_anchor_urb(urb, &tx->submitted);
964         r = usb_submit_urb(urb, GFP_ATOMIC);
965         if (r) {
966                 usb_unanchor_urb(urb);
967                 dev_dbg_f(urb_dev(urb), "error resubmit urb %p %d\n", urb, r);
968                 goto free_urb;
969         }
970 }
971
972 /**
973  * zd_usb_tx: initiates transfer of a frame of the device
974  *
975  * @usb: the zd1211rw-private USB structure
976  * @skb: a &struct sk_buff pointer
977  *
978  * This function tranmits a frame to the device. It doesn't wait for
979  * completion. The frame must contain the control set and have all the
980  * control set information available.
981  *
982  * The function returns 0 if the transfer has been successfully initiated.
983  */
984 int zd_usb_tx(struct zd_usb *usb, struct sk_buff *skb)
985 {
986         int r;
987         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
988         struct usb_device *udev = zd_usb_to_usbdev(usb);
989         struct urb *urb;
990         struct zd_usb_tx *tx = &usb->tx;
991
992         if (!atomic_read(&tx->enabled)) {
993                 r = -ENOENT;
994                 goto out;
995         }
996
997         urb = usb_alloc_urb(0, GFP_ATOMIC);
998         if (!urb) {
999                 r = -ENOMEM;
1000                 goto out;
1001         }
1002
1003         usb_fill_bulk_urb(urb, udev, usb_sndbulkpipe(udev, EP_DATA_OUT),
1004                           skb->data, skb->len, tx_urb_complete, skb);
1005
1006         info->rate_driver_data[1] = (void *)jiffies;
1007         skb_queue_tail(&tx->submitted_skbs, skb);
1008         usb_anchor_urb(urb, &tx->submitted);
1009
1010         r = usb_submit_urb(urb, GFP_ATOMIC);
1011         if (r) {
1012                 dev_dbg_f(zd_usb_dev(usb), "error submit urb %p %d\n", urb, r);
1013                 usb_unanchor_urb(urb);
1014                 skb_unlink(skb, &tx->submitted_skbs);
1015                 goto error;
1016         }
1017         tx_inc_submitted_urbs(usb);
1018         return 0;
1019 error:
1020         usb_free_urb(urb);
1021 out:
1022         return r;
1023 }
1024
1025 static bool zd_tx_timeout(struct zd_usb *usb)
1026 {
1027         struct zd_usb_tx *tx = &usb->tx;
1028         struct sk_buff_head *q = &tx->submitted_skbs;
1029         struct sk_buff *skb, *skbnext;
1030         struct ieee80211_tx_info *info;
1031         unsigned long flags, trans_start;
1032         bool have_timedout = false;
1033
1034         spin_lock_irqsave(&q->lock, flags);
1035         skb_queue_walk_safe(q, skb, skbnext) {
1036                 info = IEEE80211_SKB_CB(skb);
1037                 trans_start = (unsigned long)info->rate_driver_data[1];
1038
1039                 if (time_is_before_jiffies(trans_start + ZD_TX_TIMEOUT)) {
1040                         have_timedout = true;
1041                         break;
1042                 }
1043         }
1044         spin_unlock_irqrestore(&q->lock, flags);
1045
1046         return have_timedout;
1047 }
1048
1049 static void zd_tx_watchdog_handler(struct work_struct *work)
1050 {
1051         struct zd_usb *usb =
1052                 container_of(work, struct zd_usb, tx.watchdog_work.work);
1053         struct zd_usb_tx *tx = &usb->tx;
1054
1055         if (!atomic_read(&tx->enabled) || !tx->watchdog_enabled)
1056                 goto out;
1057         if (!zd_tx_timeout(usb))
1058                 goto out;
1059
1060         /* TX halted, try reset */
1061         dev_warn(zd_usb_dev(usb), "TX-stall detected, reseting device...");
1062
1063         usb_queue_reset_device(usb->intf);
1064
1065         /* reset will stop this worker, don't rearm */
1066         return;
1067 out:
1068         queue_delayed_work(zd_workqueue, &tx->watchdog_work,
1069                            ZD_TX_WATCHDOG_INTERVAL);
1070 }
1071
1072 void zd_tx_watchdog_enable(struct zd_usb *usb)
1073 {
1074         struct zd_usb_tx *tx = &usb->tx;
1075
1076         if (!tx->watchdog_enabled) {
1077                 dev_dbg_f(zd_usb_dev(usb), "\n");
1078                 queue_delayed_work(zd_workqueue, &tx->watchdog_work,
1079                                    ZD_TX_WATCHDOG_INTERVAL);
1080                 tx->watchdog_enabled = 1;
1081         }
1082 }
1083
1084 void zd_tx_watchdog_disable(struct zd_usb *usb)
1085 {
1086         struct zd_usb_tx *tx = &usb->tx;
1087
1088         if (tx->watchdog_enabled) {
1089                 dev_dbg_f(zd_usb_dev(usb), "\n");
1090                 tx->watchdog_enabled = 0;
1091                 cancel_delayed_work_sync(&tx->watchdog_work);
1092         }
1093 }
1094
1095 static void zd_rx_idle_timer_handler(struct work_struct *work)
1096 {
1097         struct zd_usb *usb =
1098                 container_of(work, struct zd_usb, rx.idle_work.work);
1099         struct zd_mac *mac = zd_usb_to_mac(usb);
1100
1101         if (!test_bit(ZD_DEVICE_RUNNING, &mac->flags))
1102                 return;
1103
1104         dev_dbg_f(zd_usb_dev(usb), "\n");
1105
1106         /* 30 seconds since last rx, reset rx */
1107         zd_usb_reset_rx(usb);
1108 }
1109
1110 static void zd_usb_reset_rx_idle_timer_tasklet(unsigned long param)
1111 {
1112         struct zd_usb *usb = (struct zd_usb *)param;
1113
1114         zd_usb_reset_rx_idle_timer(usb);
1115 }
1116
1117 void zd_usb_reset_rx_idle_timer(struct zd_usb *usb)
1118 {
1119         struct zd_usb_rx *rx = &usb->rx;
1120
1121         cancel_delayed_work(&rx->idle_work);
1122         queue_delayed_work(zd_workqueue, &rx->idle_work, ZD_RX_IDLE_INTERVAL);
1123 }
1124
1125 static inline void init_usb_interrupt(struct zd_usb *usb)
1126 {
1127         struct zd_usb_interrupt *intr = &usb->intr;
1128
1129         spin_lock_init(&intr->lock);
1130         intr->interval = int_urb_interval(zd_usb_to_usbdev(usb));
1131         init_completion(&intr->read_regs.completion);
1132         intr->read_regs.cr_int_addr = cpu_to_le16((u16)CR_INTERRUPT);
1133 }
1134
1135 static inline void init_usb_rx(struct zd_usb *usb)
1136 {
1137         struct zd_usb_rx *rx = &usb->rx;
1138
1139         spin_lock_init(&rx->lock);
1140         mutex_init(&rx->setup_mutex);
1141         if (interface_to_usbdev(usb->intf)->speed == USB_SPEED_HIGH) {
1142                 rx->usb_packet_size = 512;
1143         } else {
1144                 rx->usb_packet_size = 64;
1145         }
1146         ZD_ASSERT(rx->fragment_length == 0);
1147         INIT_DELAYED_WORK(&rx->idle_work, zd_rx_idle_timer_handler);
1148         rx->reset_timer_tasklet.func = zd_usb_reset_rx_idle_timer_tasklet;
1149         rx->reset_timer_tasklet.data = (unsigned long)usb;
1150 }
1151
1152 static inline void init_usb_tx(struct zd_usb *usb)
1153 {
1154         struct zd_usb_tx *tx = &usb->tx;
1155
1156         spin_lock_init(&tx->lock);
1157         atomic_set(&tx->enabled, 0);
1158         tx->stopped = 0;
1159         skb_queue_head_init(&tx->submitted_skbs);
1160         init_usb_anchor(&tx->submitted);
1161         tx->submitted_urbs = 0;
1162         tx->watchdog_enabled = 0;
1163         INIT_DELAYED_WORK(&tx->watchdog_work, zd_tx_watchdog_handler);
1164 }
1165
1166 void zd_usb_init(struct zd_usb *usb, struct ieee80211_hw *hw,
1167                  struct usb_interface *intf)
1168 {
1169         memset(usb, 0, sizeof(*usb));
1170         usb->intf = usb_get_intf(intf);
1171         usb_set_intfdata(usb->intf, hw);
1172         init_usb_anchor(&usb->submitted_cmds);
1173         init_usb_interrupt(usb);
1174         init_usb_tx(usb);
1175         init_usb_rx(usb);
1176 }
1177
1178 void zd_usb_clear(struct zd_usb *usb)
1179 {
1180         usb_set_intfdata(usb->intf, NULL);
1181         usb_put_intf(usb->intf);
1182         ZD_MEMCLEAR(usb, sizeof(*usb));
1183         /* FIXME: usb_interrupt, usb_tx, usb_rx? */
1184 }
1185
1186 static const char *speed(enum usb_device_speed speed)
1187 {
1188         switch (speed) {
1189         case USB_SPEED_LOW:
1190                 return "low";
1191         case USB_SPEED_FULL:
1192                 return "full";
1193         case USB_SPEED_HIGH:
1194                 return "high";
1195         default:
1196                 return "unknown speed";
1197         }
1198 }
1199
1200 static int scnprint_id(struct usb_device *udev, char *buffer, size_t size)
1201 {
1202         return scnprintf(buffer, size, "%04hx:%04hx v%04hx %s",
1203                 le16_to_cpu(udev->descriptor.idVendor),
1204                 le16_to_cpu(udev->descriptor.idProduct),
1205                 get_bcdDevice(udev),
1206                 speed(udev->speed));
1207 }
1208
1209 int zd_usb_scnprint_id(struct zd_usb *usb, char *buffer, size_t size)
1210 {
1211         struct usb_device *udev = interface_to_usbdev(usb->intf);
1212         return scnprint_id(udev, buffer, size);
1213 }
1214
1215 #ifdef DEBUG
1216 static void print_id(struct usb_device *udev)
1217 {
1218         char buffer[40];
1219
1220         scnprint_id(udev, buffer, sizeof(buffer));
1221         buffer[sizeof(buffer)-1] = 0;
1222         dev_dbg_f(&udev->dev, "%s\n", buffer);
1223 }
1224 #else
1225 #define print_id(udev) do { } while (0)
1226 #endif
1227
1228 static int eject_installer(struct usb_interface *intf)
1229 {
1230         struct usb_device *udev = interface_to_usbdev(intf);
1231         struct usb_host_interface *iface_desc = &intf->altsetting[0];
1232         struct usb_endpoint_descriptor *endpoint;
1233         unsigned char *cmd;
1234         u8 bulk_out_ep;
1235         int r;
1236
1237         /* Find bulk out endpoint */
1238         for (r = 1; r >= 0; r--) {
1239                 endpoint = &iface_desc->endpoint[r].desc;
1240                 if (usb_endpoint_dir_out(endpoint) &&
1241                     usb_endpoint_xfer_bulk(endpoint)) {
1242                         bulk_out_ep = endpoint->bEndpointAddress;
1243                         break;
1244                 }
1245         }
1246         if (r == -1) {
1247                 dev_err(&udev->dev,
1248                         "zd1211rw: Could not find bulk out endpoint\n");
1249                 return -ENODEV;
1250         }
1251
1252         cmd = kzalloc(31, GFP_KERNEL);
1253         if (cmd == NULL)
1254                 return -ENODEV;
1255
1256         /* USB bulk command block */
1257         cmd[0] = 0x55;  /* bulk command signature */
1258         cmd[1] = 0x53;  /* bulk command signature */
1259         cmd[2] = 0x42;  /* bulk command signature */
1260         cmd[3] = 0x43;  /* bulk command signature */
1261         cmd[14] = 6;    /* command length */
1262
1263         cmd[15] = 0x1b; /* SCSI command: START STOP UNIT */
1264         cmd[19] = 0x2;  /* eject disc */
1265
1266         dev_info(&udev->dev, "Ejecting virtual installer media...\n");
1267         r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, bulk_out_ep),
1268                 cmd, 31, NULL, 2000);
1269         kfree(cmd);
1270         if (r)
1271                 return r;
1272
1273         /* At this point, the device disconnects and reconnects with the real
1274          * ID numbers. */
1275
1276         usb_set_intfdata(intf, NULL);
1277         return 0;
1278 }
1279
1280 int zd_usb_init_hw(struct zd_usb *usb)
1281 {
1282         int r;
1283         struct zd_mac *mac = zd_usb_to_mac(usb);
1284
1285         dev_dbg_f(zd_usb_dev(usb), "\n");
1286
1287         r = upload_firmware(usb);
1288         if (r) {
1289                 dev_err(zd_usb_dev(usb),
1290                        "couldn't load firmware. Error number %d\n", r);
1291                 return r;
1292         }
1293
1294         r = usb_reset_configuration(zd_usb_to_usbdev(usb));
1295         if (r) {
1296                 dev_dbg_f(zd_usb_dev(usb),
1297                         "couldn't reset configuration. Error number %d\n", r);
1298                 return r;
1299         }
1300
1301         r = zd_mac_init_hw(mac->hw);
1302         if (r) {
1303                 dev_dbg_f(zd_usb_dev(usb),
1304                          "couldn't initialize mac. Error number %d\n", r);
1305                 return r;
1306         }
1307
1308         usb->initialized = 1;
1309         return 0;
1310 }
1311
1312 static int probe(struct usb_interface *intf, const struct usb_device_id *id)
1313 {
1314         int r;
1315         struct usb_device *udev = interface_to_usbdev(intf);
1316         struct zd_usb *usb;
1317         struct ieee80211_hw *hw = NULL;
1318
1319         print_id(udev);
1320
1321         if (id->driver_info & DEVICE_INSTALLER)
1322                 return eject_installer(intf);
1323
1324         switch (udev->speed) {
1325         case USB_SPEED_LOW:
1326         case USB_SPEED_FULL:
1327         case USB_SPEED_HIGH:
1328                 break;
1329         default:
1330                 dev_dbg_f(&intf->dev, "Unknown USB speed\n");
1331                 r = -ENODEV;
1332                 goto error;
1333         }
1334
1335         r = usb_reset_device(udev);
1336         if (r) {
1337                 dev_err(&intf->dev,
1338                         "couldn't reset usb device. Error number %d\n", r);
1339                 goto error;
1340         }
1341
1342         hw = zd_mac_alloc_hw(intf);
1343         if (hw == NULL) {
1344                 r = -ENOMEM;
1345                 goto error;
1346         }
1347
1348         usb = &zd_hw_mac(hw)->chip.usb;
1349         usb->is_zd1211b = (id->driver_info == DEVICE_ZD1211B) != 0;
1350
1351         r = zd_mac_preinit_hw(hw);
1352         if (r) {
1353                 dev_dbg_f(&intf->dev,
1354                          "couldn't initialize mac. Error number %d\n", r);
1355                 goto error;
1356         }
1357
1358         r = ieee80211_register_hw(hw);
1359         if (r) {
1360                 dev_dbg_f(&intf->dev,
1361                          "couldn't register device. Error number %d\n", r);
1362                 goto error;
1363         }
1364
1365         dev_dbg_f(&intf->dev, "successful\n");
1366         dev_info(&intf->dev, "%s\n", wiphy_name(hw->wiphy));
1367         return 0;
1368 error:
1369         usb_reset_device(interface_to_usbdev(intf));
1370         if (hw) {
1371                 zd_mac_clear(zd_hw_mac(hw));
1372                 ieee80211_free_hw(hw);
1373         }
1374         return r;
1375 }
1376
1377 static void disconnect(struct usb_interface *intf)
1378 {
1379         struct ieee80211_hw *hw = zd_intf_to_hw(intf);
1380         struct zd_mac *mac;
1381         struct zd_usb *usb;
1382
1383         /* Either something really bad happened, or we're just dealing with
1384          * a DEVICE_INSTALLER. */
1385         if (hw == NULL)
1386                 return;
1387
1388         mac = zd_hw_mac(hw);
1389         usb = &mac->chip.usb;
1390
1391         dev_dbg_f(zd_usb_dev(usb), "\n");
1392
1393         ieee80211_unregister_hw(hw);
1394
1395         /* Just in case something has gone wrong! */
1396         zd_usb_disable_tx(usb);
1397         zd_usb_disable_rx(usb);
1398         zd_usb_disable_int(usb);
1399
1400         /* If the disconnect has been caused by a removal of the
1401          * driver module, the reset allows reloading of the driver. If the
1402          * reset will not be executed here, the upload of the firmware in the
1403          * probe function caused by the reloading of the driver will fail.
1404          */
1405         usb_reset_device(interface_to_usbdev(intf));
1406
1407         zd_mac_clear(mac);
1408         ieee80211_free_hw(hw);
1409         dev_dbg(&intf->dev, "disconnected\n");
1410 }
1411
1412 static void zd_usb_resume(struct zd_usb *usb)
1413 {
1414         struct zd_mac *mac = zd_usb_to_mac(usb);
1415         int r;
1416
1417         dev_dbg_f(zd_usb_dev(usb), "\n");
1418
1419         r = zd_op_start(zd_usb_to_hw(usb));
1420         if (r < 0) {
1421                 dev_warn(zd_usb_dev(usb), "Device resume failed "
1422                          "with error code %d. Retrying...\n", r);
1423                 if (usb->was_running)
1424                         set_bit(ZD_DEVICE_RUNNING, &mac->flags);
1425                 usb_queue_reset_device(usb->intf);
1426                 return;
1427         }
1428
1429         if (mac->type != NL80211_IFTYPE_UNSPECIFIED) {
1430                 r = zd_restore_settings(mac);
1431                 if (r < 0) {
1432                         dev_dbg(zd_usb_dev(usb),
1433                                 "failed to restore settings, %d\n", r);
1434                         return;
1435                 }
1436         }
1437 }
1438
1439 static void zd_usb_stop(struct zd_usb *usb)
1440 {
1441         dev_dbg_f(zd_usb_dev(usb), "\n");
1442
1443         zd_op_stop(zd_usb_to_hw(usb));
1444
1445         zd_usb_disable_tx(usb);
1446         zd_usb_disable_rx(usb);
1447         zd_usb_disable_int(usb);
1448
1449         usb->initialized = 0;
1450 }
1451
1452 static int pre_reset(struct usb_interface *intf)
1453 {
1454         struct ieee80211_hw *hw = usb_get_intfdata(intf);
1455         struct zd_mac *mac;
1456         struct zd_usb *usb;
1457
1458         if (!hw || intf->condition != USB_INTERFACE_BOUND)
1459                 return 0;
1460
1461         mac = zd_hw_mac(hw);
1462         usb = &mac->chip.usb;
1463
1464         usb->was_running = test_bit(ZD_DEVICE_RUNNING, &mac->flags);
1465
1466         zd_usb_stop(usb);
1467
1468         mutex_lock(&mac->chip.mutex);
1469         return 0;
1470 }
1471
1472 static int post_reset(struct usb_interface *intf)
1473 {
1474         struct ieee80211_hw *hw = usb_get_intfdata(intf);
1475         struct zd_mac *mac;
1476         struct zd_usb *usb;
1477
1478         if (!hw || intf->condition != USB_INTERFACE_BOUND)
1479                 return 0;
1480
1481         mac = zd_hw_mac(hw);
1482         usb = &mac->chip.usb;
1483
1484         mutex_unlock(&mac->chip.mutex);
1485
1486         if (usb->was_running)
1487                 zd_usb_resume(usb);
1488         return 0;
1489 }
1490
1491 static struct usb_driver driver = {
1492         .name           = KBUILD_MODNAME,
1493         .id_table       = usb_ids,
1494         .probe          = probe,
1495         .disconnect     = disconnect,
1496         .pre_reset      = pre_reset,
1497         .post_reset     = post_reset,
1498 };
1499
1500 struct workqueue_struct *zd_workqueue;
1501
1502 static int __init usb_init(void)
1503 {
1504         int r;
1505
1506         pr_debug("%s usb_init()\n", driver.name);
1507
1508         zd_workqueue = create_singlethread_workqueue(driver.name);
1509         if (zd_workqueue == NULL) {
1510                 printk(KERN_ERR "%s couldn't create workqueue\n", driver.name);
1511                 return -ENOMEM;
1512         }
1513
1514         r = usb_register(&driver);
1515         if (r) {
1516                 destroy_workqueue(zd_workqueue);
1517                 printk(KERN_ERR "%s usb_register() failed. Error number %d\n",
1518                        driver.name, r);
1519                 return r;
1520         }
1521
1522         pr_debug("%s initialized\n", driver.name);
1523         return 0;
1524 }
1525
1526 static void __exit usb_exit(void)
1527 {
1528         pr_debug("%s usb_exit()\n", driver.name);
1529         usb_deregister(&driver);
1530         destroy_workqueue(zd_workqueue);
1531 }
1532
1533 module_init(usb_init);
1534 module_exit(usb_exit);
1535
1536 static int zd_ep_regs_out_msg(struct usb_device *udev, void *data, int len,
1537                               int *actual_length, int timeout)
1538 {
1539         /* In USB 2.0 mode EP_REGS_OUT endpoint is interrupt type. However in
1540          * USB 1.1 mode endpoint is bulk. Select correct type URB by endpoint
1541          * descriptor.
1542          */
1543         struct usb_host_endpoint *ep;
1544         unsigned int pipe;
1545
1546         pipe = usb_sndintpipe(udev, EP_REGS_OUT);
1547         ep = usb_pipe_endpoint(udev, pipe);
1548         if (!ep)
1549                 return -EINVAL;
1550
1551         if (usb_endpoint_xfer_int(&ep->desc)) {
1552                 return usb_interrupt_msg(udev, pipe, data, len,
1553                                          actual_length, timeout);
1554         } else {
1555                 pipe = usb_sndbulkpipe(udev, EP_REGS_OUT);
1556                 return usb_bulk_msg(udev, pipe, data, len, actual_length,
1557                                     timeout);
1558         }
1559 }
1560
1561 static int usb_int_regs_length(unsigned int count)
1562 {
1563         return sizeof(struct usb_int_regs) + count * sizeof(struct reg_data);
1564 }
1565
1566 static void prepare_read_regs_int(struct zd_usb *usb)
1567 {
1568         struct zd_usb_interrupt *intr = &usb->intr;
1569
1570         spin_lock_irq(&intr->lock);
1571         intr->read_regs_enabled = 1;
1572         INIT_COMPLETION(intr->read_regs.completion);
1573         spin_unlock_irq(&intr->lock);
1574 }
1575
1576 static void disable_read_regs_int(struct zd_usb *usb)
1577 {
1578         struct zd_usb_interrupt *intr = &usb->intr;
1579
1580         spin_lock_irq(&intr->lock);
1581         intr->read_regs_enabled = 0;
1582         spin_unlock_irq(&intr->lock);
1583 }
1584
1585 static int get_results(struct zd_usb *usb, u16 *values,
1586                        struct usb_req_read_regs *req, unsigned int count)
1587 {
1588         int r;
1589         int i;
1590         struct zd_usb_interrupt *intr = &usb->intr;
1591         struct read_regs_int *rr = &intr->read_regs;
1592         struct usb_int_regs *regs = (struct usb_int_regs *)rr->buffer;
1593
1594         spin_lock_irq(&intr->lock);
1595
1596         r = -EIO;
1597         /* The created block size seems to be larger than expected.
1598          * However results appear to be correct.
1599          */
1600         if (rr->length < usb_int_regs_length(count)) {
1601                 dev_dbg_f(zd_usb_dev(usb),
1602                          "error: actual length %d less than expected %d\n",
1603                          rr->length, usb_int_regs_length(count));
1604                 goto error_unlock;
1605         }
1606         if (rr->length > sizeof(rr->buffer)) {
1607                 dev_dbg_f(zd_usb_dev(usb),
1608                          "error: actual length %d exceeds buffer size %zu\n",
1609                          rr->length, sizeof(rr->buffer));
1610                 goto error_unlock;
1611         }
1612
1613         for (i = 0; i < count; i++) {
1614                 struct reg_data *rd = &regs->regs[i];
1615                 if (rd->addr != req->addr[i]) {
1616                         dev_dbg_f(zd_usb_dev(usb),
1617                                  "rd[%d] addr %#06hx expected %#06hx\n", i,
1618                                  le16_to_cpu(rd->addr),
1619                                  le16_to_cpu(req->addr[i]));
1620                         goto error_unlock;
1621                 }
1622                 values[i] = le16_to_cpu(rd->value);
1623         }
1624
1625         r = 0;
1626 error_unlock:
1627         spin_unlock_irq(&intr->lock);
1628         return r;
1629 }
1630
1631 int zd_usb_ioread16v(struct zd_usb *usb, u16 *values,
1632                      const zd_addr_t *addresses, unsigned int count)
1633 {
1634         int r;
1635         int i, req_len, actual_req_len;
1636         struct usb_device *udev;
1637         struct usb_req_read_regs *req = NULL;
1638         unsigned long timeout;
1639
1640         if (count < 1) {
1641                 dev_dbg_f(zd_usb_dev(usb), "error: count is zero\n");
1642                 return -EINVAL;
1643         }
1644         if (count > USB_MAX_IOREAD16_COUNT) {
1645                 dev_dbg_f(zd_usb_dev(usb),
1646                          "error: count %u exceeds possible max %u\n",
1647                          count, USB_MAX_IOREAD16_COUNT);
1648                 return -EINVAL;
1649         }
1650         if (in_atomic()) {
1651                 dev_dbg_f(zd_usb_dev(usb),
1652                          "error: io in atomic context not supported\n");
1653                 return -EWOULDBLOCK;
1654         }
1655         if (!usb_int_enabled(usb)) {
1656                 dev_dbg_f(zd_usb_dev(usb),
1657                           "error: usb interrupt not enabled\n");
1658                 return -EWOULDBLOCK;
1659         }
1660
1661         ZD_ASSERT(mutex_is_locked(&zd_usb_to_chip(usb)->mutex));
1662         BUILD_BUG_ON(sizeof(struct usb_req_read_regs) + USB_MAX_IOREAD16_COUNT *
1663                      sizeof(__le16) > sizeof(usb->req_buf));
1664         BUG_ON(sizeof(struct usb_req_read_regs) + count * sizeof(__le16) >
1665                sizeof(usb->req_buf));
1666
1667         req_len = sizeof(struct usb_req_read_regs) + count * sizeof(__le16);
1668         req = (void *)usb->req_buf;
1669
1670         req->id = cpu_to_le16(USB_REQ_READ_REGS);
1671         for (i = 0; i < count; i++)
1672                 req->addr[i] = cpu_to_le16((u16)addresses[i]);
1673
1674         udev = zd_usb_to_usbdev(usb);
1675         prepare_read_regs_int(usb);
1676         r = zd_ep_regs_out_msg(udev, req, req_len, &actual_req_len, 50 /*ms*/);
1677         if (r) {
1678                 dev_dbg_f(zd_usb_dev(usb),
1679                         "error in zd_ep_regs_out_msg(). Error number %d\n", r);
1680                 goto error;
1681         }
1682         if (req_len != actual_req_len) {
1683                 dev_dbg_f(zd_usb_dev(usb), "error in zd_ep_regs_out_msg()\n"
1684                         " req_len %d != actual_req_len %d\n",
1685                         req_len, actual_req_len);
1686                 r = -EIO;
1687                 goto error;
1688         }
1689
1690         timeout = wait_for_completion_timeout(&usb->intr.read_regs.completion,
1691                                               msecs_to_jiffies(50));
1692         if (!timeout) {
1693                 disable_read_regs_int(usb);
1694                 dev_dbg_f(zd_usb_dev(usb), "read timed out\n");
1695                 r = -ETIMEDOUT;
1696                 goto error;
1697         }
1698
1699         r = get_results(usb, values, req, count);
1700 error:
1701         return r;
1702 }
1703
1704 static void iowrite16v_urb_complete(struct urb *urb)
1705 {
1706         struct zd_usb *usb = urb->context;
1707
1708         if (urb->status && !usb->cmd_error)
1709                 usb->cmd_error = urb->status;
1710
1711         if (!usb->cmd_error &&
1712                         urb->actual_length != urb->transfer_buffer_length)
1713                 usb->cmd_error = -EIO;
1714 }
1715
1716 static int zd_submit_waiting_urb(struct zd_usb *usb, bool last)
1717 {
1718         int r = 0;
1719         struct urb *urb = usb->urb_async_waiting;
1720
1721         if (!urb)
1722                 return 0;
1723
1724         usb->urb_async_waiting = NULL;
1725
1726         if (!last)
1727                 urb->transfer_flags |= URB_NO_INTERRUPT;
1728
1729         usb_anchor_urb(urb, &usb->submitted_cmds);
1730         r = usb_submit_urb(urb, GFP_KERNEL);
1731         if (r) {
1732                 usb_unanchor_urb(urb);
1733                 dev_dbg_f(zd_usb_dev(usb),
1734                         "error in usb_submit_urb(). Error number %d\n", r);
1735                 goto error;
1736         }
1737
1738         /* fall-through with r == 0 */
1739 error:
1740         usb_free_urb(urb);
1741         return r;
1742 }
1743
1744 void zd_usb_iowrite16v_async_start(struct zd_usb *usb)
1745 {
1746         ZD_ASSERT(usb_anchor_empty(&usb->submitted_cmds));
1747         ZD_ASSERT(usb->urb_async_waiting == NULL);
1748         ZD_ASSERT(!usb->in_async);
1749
1750         ZD_ASSERT(mutex_is_locked(&zd_usb_to_chip(usb)->mutex));
1751
1752         usb->in_async = 1;
1753         usb->cmd_error = 0;
1754         usb->urb_async_waiting = NULL;
1755 }
1756
1757 int zd_usb_iowrite16v_async_end(struct zd_usb *usb, unsigned int timeout)
1758 {
1759         int r;
1760
1761         ZD_ASSERT(mutex_is_locked(&zd_usb_to_chip(usb)->mutex));
1762         ZD_ASSERT(usb->in_async);
1763
1764         /* Submit last iowrite16v URB */
1765         r = zd_submit_waiting_urb(usb, true);
1766         if (r) {
1767                 dev_dbg_f(zd_usb_dev(usb),
1768                         "error in zd_submit_waiting_usb(). "
1769                         "Error number %d\n", r);
1770
1771                 usb_kill_anchored_urbs(&usb->submitted_cmds);
1772                 goto error;
1773         }
1774
1775         if (timeout)
1776                 timeout = usb_wait_anchor_empty_timeout(&usb->submitted_cmds,
1777                                                         timeout);
1778         if (!timeout) {
1779                 usb_kill_anchored_urbs(&usb->submitted_cmds);
1780                 if (usb->cmd_error == -ENOENT) {
1781                         dev_dbg_f(zd_usb_dev(usb), "timed out");
1782                         r = -ETIMEDOUT;
1783                         goto error;
1784                 }
1785         }
1786
1787         r = usb->cmd_error;
1788 error:
1789         usb->in_async = 0;
1790         return r;
1791 }
1792
1793 int zd_usb_iowrite16v_async(struct zd_usb *usb, const struct zd_ioreq16 *ioreqs,
1794                             unsigned int count)
1795 {
1796         int r;
1797         struct usb_device *udev;
1798         struct usb_req_write_regs *req = NULL;
1799         int i, req_len;
1800         struct urb *urb;
1801         struct usb_host_endpoint *ep;
1802
1803         ZD_ASSERT(mutex_is_locked(&zd_usb_to_chip(usb)->mutex));
1804         ZD_ASSERT(usb->in_async);
1805
1806         if (count == 0)
1807                 return 0;
1808         if (count > USB_MAX_IOWRITE16_COUNT) {
1809                 dev_dbg_f(zd_usb_dev(usb),
1810                         "error: count %u exceeds possible max %u\n",
1811                         count, USB_MAX_IOWRITE16_COUNT);
1812                 return -EINVAL;
1813         }
1814         if (in_atomic()) {
1815                 dev_dbg_f(zd_usb_dev(usb),
1816                         "error: io in atomic context not supported\n");
1817                 return -EWOULDBLOCK;
1818         }
1819
1820         udev = zd_usb_to_usbdev(usb);
1821
1822         ep = usb_pipe_endpoint(udev, usb_sndintpipe(udev, EP_REGS_OUT));
1823         if (!ep)
1824                 return -ENOENT;
1825
1826         urb = usb_alloc_urb(0, GFP_KERNEL);
1827         if (!urb)
1828                 return -ENOMEM;
1829
1830         req_len = sizeof(struct usb_req_write_regs) +
1831                   count * sizeof(struct reg_data);
1832         req = kmalloc(req_len, GFP_KERNEL);
1833         if (!req) {
1834                 r = -ENOMEM;
1835                 goto error;
1836         }
1837
1838         req->id = cpu_to_le16(USB_REQ_WRITE_REGS);
1839         for (i = 0; i < count; i++) {
1840                 struct reg_data *rw  = &req->reg_writes[i];
1841                 rw->addr = cpu_to_le16((u16)ioreqs[i].addr);
1842                 rw->value = cpu_to_le16(ioreqs[i].value);
1843         }
1844
1845         /* In USB 2.0 mode endpoint is interrupt type. However in USB 1.1 mode
1846          * endpoint is bulk. Select correct type URB by endpoint descriptor.
1847          */
1848         if (usb_endpoint_xfer_int(&ep->desc))
1849                 usb_fill_int_urb(urb, udev, usb_sndintpipe(udev, EP_REGS_OUT),
1850                                  req, req_len, iowrite16v_urb_complete, usb,
1851                                  ep->desc.bInterval);
1852         else
1853                 usb_fill_bulk_urb(urb, udev, usb_sndbulkpipe(udev, EP_REGS_OUT),
1854                                   req, req_len, iowrite16v_urb_complete, usb);
1855
1856         urb->transfer_flags |= URB_FREE_BUFFER;
1857
1858         /* Submit previous URB */
1859         r = zd_submit_waiting_urb(usb, false);
1860         if (r) {
1861                 dev_dbg_f(zd_usb_dev(usb),
1862                         "error in zd_submit_waiting_usb(). "
1863                         "Error number %d\n", r);
1864                 goto error;
1865         }
1866
1867         /* Delay submit so that URB_NO_INTERRUPT flag can be set for all URBs
1868          * of currect batch except for very last.
1869          */
1870         usb->urb_async_waiting = urb;
1871         return 0;
1872 error:
1873         usb_free_urb(urb);
1874         return r;
1875 }
1876
1877 int zd_usb_iowrite16v(struct zd_usb *usb, const struct zd_ioreq16 *ioreqs,
1878                         unsigned int count)
1879 {
1880         int r;
1881
1882         zd_usb_iowrite16v_async_start(usb);
1883         r = zd_usb_iowrite16v_async(usb, ioreqs, count);
1884         if (r) {
1885                 zd_usb_iowrite16v_async_end(usb, 0);
1886                 return r;
1887         }
1888         return zd_usb_iowrite16v_async_end(usb, 50 /* ms */);
1889 }
1890
1891 int zd_usb_rfwrite(struct zd_usb *usb, u32 value, u8 bits)
1892 {
1893         int r;
1894         struct usb_device *udev;
1895         struct usb_req_rfwrite *req = NULL;
1896         int i, req_len, actual_req_len;
1897         u16 bit_value_template;
1898
1899         if (in_atomic()) {
1900                 dev_dbg_f(zd_usb_dev(usb),
1901                         "error: io in atomic context not supported\n");
1902                 return -EWOULDBLOCK;
1903         }
1904         if (bits < USB_MIN_RFWRITE_BIT_COUNT) {
1905                 dev_dbg_f(zd_usb_dev(usb),
1906                         "error: bits %d are smaller than"
1907                         " USB_MIN_RFWRITE_BIT_COUNT %d\n",
1908                         bits, USB_MIN_RFWRITE_BIT_COUNT);
1909                 return -EINVAL;
1910         }
1911         if (bits > USB_MAX_RFWRITE_BIT_COUNT) {
1912                 dev_dbg_f(zd_usb_dev(usb),
1913                         "error: bits %d exceed USB_MAX_RFWRITE_BIT_COUNT %d\n",
1914                         bits, USB_MAX_RFWRITE_BIT_COUNT);
1915                 return -EINVAL;
1916         }
1917 #ifdef DEBUG
1918         if (value & (~0UL << bits)) {
1919                 dev_dbg_f(zd_usb_dev(usb),
1920                         "error: value %#09x has bits >= %d set\n",
1921                         value, bits);
1922                 return -EINVAL;
1923         }
1924 #endif /* DEBUG */
1925
1926         dev_dbg_f(zd_usb_dev(usb), "value %#09x bits %d\n", value, bits);
1927
1928         r = zd_usb_ioread16(usb, &bit_value_template, ZD_CR203);
1929         if (r) {
1930                 dev_dbg_f(zd_usb_dev(usb),
1931                         "error %d: Couldn't read ZD_CR203\n", r);
1932                 return r;
1933         }
1934         bit_value_template &= ~(RF_IF_LE|RF_CLK|RF_DATA);
1935
1936         ZD_ASSERT(mutex_is_locked(&zd_usb_to_chip(usb)->mutex));
1937         BUILD_BUG_ON(sizeof(struct usb_req_rfwrite) +
1938                      USB_MAX_RFWRITE_BIT_COUNT * sizeof(__le16) >
1939                      sizeof(usb->req_buf));
1940         BUG_ON(sizeof(struct usb_req_rfwrite) + bits * sizeof(__le16) >
1941                sizeof(usb->req_buf));
1942
1943         req_len = sizeof(struct usb_req_rfwrite) + bits * sizeof(__le16);
1944         req = (void *)usb->req_buf;
1945
1946         req->id = cpu_to_le16(USB_REQ_WRITE_RF);
1947         /* 1: 3683a, but not used in ZYDAS driver */
1948         req->value = cpu_to_le16(2);
1949         req->bits = cpu_to_le16(bits);
1950
1951         for (i = 0; i < bits; i++) {
1952                 u16 bv = bit_value_template;
1953                 if (value & (1 << (bits-1-i)))
1954                         bv |= RF_DATA;
1955                 req->bit_values[i] = cpu_to_le16(bv);
1956         }
1957
1958         udev = zd_usb_to_usbdev(usb);
1959         r = zd_ep_regs_out_msg(udev, req, req_len, &actual_req_len, 50 /*ms*/);
1960         if (r) {
1961                 dev_dbg_f(zd_usb_dev(usb),
1962                         "error in zd_ep_regs_out_msg(). Error number %d\n", r);
1963                 goto out;
1964         }
1965         if (req_len != actual_req_len) {
1966                 dev_dbg_f(zd_usb_dev(usb), "error in zd_ep_regs_out_msg()"
1967                         " req_len %d != actual_req_len %d\n",
1968                         req_len, actual_req_len);
1969                 r = -EIO;
1970                 goto out;
1971         }
1972
1973         /* FALL-THROUGH with r == 0 */
1974 out:
1975         return r;
1976 }