ca54830dfdb59ef9a77ed4c16a1e8b059d0681a0
[pandora-kernel.git] / drivers / net / wireless / zd1211rw / zd_usb.c
1 /* zd_usb.c
2  *
3  * This program is free software; you can redistribute it and/or modify
4  * it under the terms of the GNU General Public License as published by
5  * the Free Software Foundation; either version 2 of the License, or
6  * (at your option) any later version.
7  *
8  * This program is distributed in the hope that it will be useful,
9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11  * GNU General Public License for more details.
12  *
13  * You should have received a copy of the GNU General Public License
14  * along with this program; if not, write to the Free Software
15  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
16  */
17
18 #include <asm/unaligned.h>
19 #include <linux/kernel.h>
20 #include <linux/init.h>
21 #include <linux/module.h>
22 #include <linux/firmware.h>
23 #include <linux/device.h>
24 #include <linux/errno.h>
25 #include <linux/skbuff.h>
26 #include <linux/usb.h>
27 #include <linux/workqueue.h>
28 #include <net/ieee80211.h>
29
30 #include "zd_def.h"
31 #include "zd_netdev.h"
32 #include "zd_mac.h"
33 #include "zd_usb.h"
34 #include "zd_util.h"
35
36 static struct usb_device_id usb_ids[] = {
37         /* ZD1211 */
38         { USB_DEVICE(0x0ace, 0x1211), .driver_info = DEVICE_ZD1211 },
39         { USB_DEVICE(0x07b8, 0x6001), .driver_info = DEVICE_ZD1211 },
40         { USB_DEVICE(0x126f, 0xa006), .driver_info = DEVICE_ZD1211 },
41         { USB_DEVICE(0x6891, 0xa727), .driver_info = DEVICE_ZD1211 },
42         { USB_DEVICE(0x0df6, 0x9071), .driver_info = DEVICE_ZD1211 },
43         { USB_DEVICE(0x157e, 0x300b), .driver_info = DEVICE_ZD1211 },
44         { USB_DEVICE(0x079b, 0x004a), .driver_info = DEVICE_ZD1211 },
45         { USB_DEVICE(0x1740, 0x2000), .driver_info = DEVICE_ZD1211 },
46         { USB_DEVICE(0x157e, 0x3204), .driver_info = DEVICE_ZD1211 },
47         { USB_DEVICE(0x0586, 0x3402), .driver_info = DEVICE_ZD1211 },
48         { USB_DEVICE(0x0b3b, 0x5630), .driver_info = DEVICE_ZD1211 },
49         { USB_DEVICE(0x0b05, 0x170c), .driver_info = DEVICE_ZD1211 },
50         { USB_DEVICE(0x1435, 0x0711), .driver_info = DEVICE_ZD1211 },
51         { USB_DEVICE(0x0586, 0x3409), .driver_info = DEVICE_ZD1211 },
52         { USB_DEVICE(0x0b3b, 0x1630), .driver_info = DEVICE_ZD1211 },
53         { USB_DEVICE(0x0586, 0x3401), .driver_info = DEVICE_ZD1211 },
54         { USB_DEVICE(0x14ea, 0xab13), .driver_info = DEVICE_ZD1211 },
55         /* ZD1211B */
56         { USB_DEVICE(0x0ace, 0x1215), .driver_info = DEVICE_ZD1211B },
57         { USB_DEVICE(0x157e, 0x300d), .driver_info = DEVICE_ZD1211B },
58         { USB_DEVICE(0x079b, 0x0062), .driver_info = DEVICE_ZD1211B },
59         { USB_DEVICE(0x1582, 0x6003), .driver_info = DEVICE_ZD1211B },
60         /* "Driverless" devices that need ejecting */
61         { USB_DEVICE(0x0ace, 0x2011), .driver_info = DEVICE_INSTALLER },
62         {}
63 };
64
65 MODULE_LICENSE("GPL");
66 MODULE_DESCRIPTION("USB driver for devices with the ZD1211 chip.");
67 MODULE_AUTHOR("Ulrich Kunitz");
68 MODULE_AUTHOR("Daniel Drake");
69 MODULE_VERSION("1.0");
70 MODULE_DEVICE_TABLE(usb, usb_ids);
71
72 #define FW_ZD1211_PREFIX        "zd1211/zd1211_"
73 #define FW_ZD1211B_PREFIX       "zd1211/zd1211b_"
74
75 /* register address handling */
76
77 #ifdef DEBUG
78 static int check_addr(struct zd_usb *usb, zd_addr_t addr)
79 {
80         u32 base = ZD_ADDR_BASE(addr);
81         u32 offset = ZD_OFFSET(addr);
82
83         if ((u32)addr & ADDR_ZERO_MASK)
84                 goto invalid_address;
85         switch (base) {
86         case USB_BASE:
87                 break;
88         case CR_BASE:
89                 if (offset > CR_MAX_OFFSET) {
90                         dev_dbg(zd_usb_dev(usb),
91                                 "CR offset %#010x larger than"
92                                 " CR_MAX_OFFSET %#10x\n",
93                                 offset, CR_MAX_OFFSET);
94                         goto invalid_address;
95                 }
96                 if (offset & 1) {
97                         dev_dbg(zd_usb_dev(usb),
98                                 "CR offset %#010x is not a multiple of 2\n",
99                                 offset);
100                         goto invalid_address;
101                 }
102                 break;
103         case E2P_BASE:
104                 if (offset > E2P_MAX_OFFSET) {
105                         dev_dbg(zd_usb_dev(usb),
106                                 "E2P offset %#010x larger than"
107                                 " E2P_MAX_OFFSET %#010x\n",
108                                 offset, E2P_MAX_OFFSET);
109                         goto invalid_address;
110                 }
111                 break;
112         case FW_BASE:
113                 if (!usb->fw_base_offset) {
114                         dev_dbg(zd_usb_dev(usb),
115                                "ERROR: fw base offset has not been set\n");
116                         return -EAGAIN;
117                 }
118                 if (offset > FW_MAX_OFFSET) {
119                         dev_dbg(zd_usb_dev(usb),
120                                 "FW offset %#10x is larger than"
121                                 " FW_MAX_OFFSET %#010x\n",
122                                 offset, FW_MAX_OFFSET);
123                         goto invalid_address;
124                 }
125                 break;
126         default:
127                 dev_dbg(zd_usb_dev(usb),
128                         "address has unsupported base %#010x\n", addr);
129                 goto invalid_address;
130         }
131
132         return 0;
133 invalid_address:
134         dev_dbg(zd_usb_dev(usb),
135                 "ERROR: invalid address: %#010x\n", addr);
136         return -EINVAL;
137 }
138 #endif /* DEBUG */
139
140 static u16 usb_addr(struct zd_usb *usb, zd_addr_t addr)
141 {
142         u32 base;
143         u16 offset;
144
145         base = ZD_ADDR_BASE(addr);
146         offset = ZD_OFFSET(addr);
147
148         ZD_ASSERT(check_addr(usb, addr) == 0);
149
150         switch (base) {
151         case CR_BASE:
152                 offset += CR_BASE_OFFSET;
153                 break;
154         case E2P_BASE:
155                 offset += E2P_BASE_OFFSET;
156                 break;
157         case FW_BASE:
158                 offset += usb->fw_base_offset;
159                 break;
160         }
161
162         return offset;
163 }
164
165 /* USB device initialization */
166
167 static int request_fw_file(
168         const struct firmware **fw, const char *name, struct device *device)
169 {
170         int r;
171
172         dev_dbg_f(device, "fw name %s\n", name);
173
174         r = request_firmware(fw, name, device);
175         if (r)
176                 dev_err(device,
177                        "Could not load firmware file %s. Error number %d\n",
178                        name, r);
179         return r;
180 }
181
182 static inline u16 get_bcdDevice(const struct usb_device *udev)
183 {
184         return le16_to_cpu(udev->descriptor.bcdDevice);
185 }
186
187 enum upload_code_flags {
188         REBOOT = 1,
189 };
190
191 /* Ensures that MAX_TRANSFER_SIZE is even. */
192 #define MAX_TRANSFER_SIZE (USB_MAX_TRANSFER_SIZE & ~1)
193
194 static int upload_code(struct usb_device *udev,
195         const u8 *data, size_t size, u16 code_offset, int flags)
196 {
197         u8 *p;
198         int r;
199
200         /* USB request blocks need "kmalloced" buffers.
201          */
202         p = kmalloc(MAX_TRANSFER_SIZE, GFP_KERNEL);
203         if (!p) {
204                 dev_err(&udev->dev, "out of memory\n");
205                 r = -ENOMEM;
206                 goto error;
207         }
208
209         size &= ~1;
210         while (size > 0) {
211                 size_t transfer_size = size <= MAX_TRANSFER_SIZE ?
212                         size : MAX_TRANSFER_SIZE;
213
214                 dev_dbg_f(&udev->dev, "transfer size %zu\n", transfer_size);
215
216                 memcpy(p, data, transfer_size);
217                 r = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
218                         USB_REQ_FIRMWARE_DOWNLOAD,
219                         USB_DIR_OUT | USB_TYPE_VENDOR,
220                         code_offset, 0, p, transfer_size, 1000 /* ms */);
221                 if (r < 0) {
222                         dev_err(&udev->dev,
223                                "USB control request for firmware upload"
224                                " failed. Error number %d\n", r);
225                         goto error;
226                 }
227                 transfer_size = r & ~1;
228
229                 size -= transfer_size;
230                 data += transfer_size;
231                 code_offset += transfer_size/sizeof(u16);
232         }
233
234         if (flags & REBOOT) {
235                 u8 ret;
236
237                 r = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
238                         USB_REQ_FIRMWARE_CONFIRM,
239                         USB_DIR_IN | USB_TYPE_VENDOR,
240                         0, 0, &ret, sizeof(ret), 5000 /* ms */);
241                 if (r != sizeof(ret)) {
242                         dev_err(&udev->dev,
243                                 "control request firmeware confirmation failed."
244                                 " Return value %d\n", r);
245                         if (r >= 0)
246                                 r = -ENODEV;
247                         goto error;
248                 }
249                 if (ret & 0x80) {
250                         dev_err(&udev->dev,
251                                 "Internal error while downloading."
252                                 " Firmware confirm return value %#04x\n",
253                                 (unsigned int)ret);
254                         r = -ENODEV;
255                         goto error;
256                 }
257                 dev_dbg_f(&udev->dev, "firmware confirm return value %#04x\n",
258                         (unsigned int)ret);
259         }
260
261         r = 0;
262 error:
263         kfree(p);
264         return r;
265 }
266
267 static u16 get_word(const void *data, u16 offset)
268 {
269         const __le16 *p = data;
270         return le16_to_cpu(p[offset]);
271 }
272
273 static char *get_fw_name(char *buffer, size_t size, u8 device_type,
274                        const char* postfix)
275 {
276         scnprintf(buffer, size, "%s%s",
277                 device_type == DEVICE_ZD1211B ?
278                         FW_ZD1211B_PREFIX : FW_ZD1211_PREFIX,
279                 postfix);
280         return buffer;
281 }
282
283 static int handle_version_mismatch(struct usb_device *udev, u8 device_type,
284         const struct firmware *ub_fw)
285 {
286         const struct firmware *ur_fw = NULL;
287         int offset;
288         int r = 0;
289         char fw_name[128];
290
291         r = request_fw_file(&ur_fw,
292                 get_fw_name(fw_name, sizeof(fw_name), device_type, "ur"),
293                 &udev->dev);
294         if (r)
295                 goto error;
296
297         r = upload_code(udev, ur_fw->data, ur_fw->size, FW_START_OFFSET,
298                 REBOOT);
299         if (r)
300                 goto error;
301
302         offset = ((EEPROM_REGS_OFFSET + EEPROM_REGS_SIZE) * sizeof(u16));
303         r = upload_code(udev, ub_fw->data + offset, ub_fw->size - offset,
304                 E2P_BASE_OFFSET + EEPROM_REGS_SIZE, REBOOT);
305
306         /* At this point, the vendor driver downloads the whole firmware
307          * image, hacks around with version IDs, and uploads it again,
308          * completely overwriting the boot code. We do not do this here as
309          * it is not required on any tested devices, and it is suspected to
310          * cause problems. */
311 error:
312         release_firmware(ur_fw);
313         return r;
314 }
315
316 static int upload_firmware(struct usb_device *udev, u8 device_type)
317 {
318         int r;
319         u16 fw_bcdDevice;
320         u16 bcdDevice;
321         const struct firmware *ub_fw = NULL;
322         const struct firmware *uph_fw = NULL;
323         char fw_name[128];
324
325         bcdDevice = get_bcdDevice(udev);
326
327         r = request_fw_file(&ub_fw,
328                 get_fw_name(fw_name, sizeof(fw_name), device_type,  "ub"),
329                 &udev->dev);
330         if (r)
331                 goto error;
332
333         fw_bcdDevice = get_word(ub_fw->data, EEPROM_REGS_OFFSET);
334
335         if (fw_bcdDevice != bcdDevice) {
336                 dev_info(&udev->dev,
337                         "firmware version %#06x and device bootcode version "
338                         "%#06x differ\n", fw_bcdDevice, bcdDevice);
339                 if (bcdDevice <= 0x4313)
340                         dev_warn(&udev->dev, "device has old bootcode, please "
341                                 "report success or failure\n");
342
343                 r = handle_version_mismatch(udev, device_type, ub_fw);
344                 if (r)
345                         goto error;
346         } else {
347                 dev_dbg_f(&udev->dev,
348                         "firmware device id %#06x is equal to the "
349                         "actual device id\n", fw_bcdDevice);
350         }
351
352
353         r = request_fw_file(&uph_fw,
354                 get_fw_name(fw_name, sizeof(fw_name), device_type, "uphr"),
355                 &udev->dev);
356         if (r)
357                 goto error;
358
359         r = upload_code(udev, uph_fw->data, uph_fw->size, FW_START_OFFSET,
360                         REBOOT);
361         if (r) {
362                 dev_err(&udev->dev,
363                         "Could not upload firmware code uph. Error number %d\n",
364                         r);
365         }
366
367         /* FALL-THROUGH */
368 error:
369         release_firmware(ub_fw);
370         release_firmware(uph_fw);
371         return r;
372 }
373
374 #define urb_dev(urb) (&(urb)->dev->dev)
375
376 static inline void handle_regs_int(struct urb *urb)
377 {
378         struct zd_usb *usb = urb->context;
379         struct zd_usb_interrupt *intr = &usb->intr;
380         int len;
381
382         ZD_ASSERT(in_interrupt());
383         spin_lock(&intr->lock);
384
385         if (intr->read_regs_enabled) {
386                 intr->read_regs.length = len = urb->actual_length;
387
388                 if (len > sizeof(intr->read_regs.buffer))
389                         len = sizeof(intr->read_regs.buffer);
390                 memcpy(intr->read_regs.buffer, urb->transfer_buffer, len);
391                 intr->read_regs_enabled = 0;
392                 complete(&intr->read_regs.completion);
393                 goto out;
394         }
395
396         dev_dbg_f(urb_dev(urb), "regs interrupt ignored\n");
397 out:
398         spin_unlock(&intr->lock);
399 }
400
401 static inline void handle_retry_failed_int(struct urb *urb)
402 {
403         dev_dbg_f(urb_dev(urb), "retry failed interrupt\n");
404 }
405
406
407 static void int_urb_complete(struct urb *urb)
408 {
409         int r;
410         struct usb_int_header *hdr;
411
412         switch (urb->status) {
413         case 0:
414                 break;
415         case -ESHUTDOWN:
416         case -EINVAL:
417         case -ENODEV:
418         case -ENOENT:
419         case -ECONNRESET:
420         case -EPIPE:
421                 goto kfree;
422         default:
423                 goto resubmit;
424         }
425
426         if (urb->actual_length < sizeof(hdr)) {
427                 dev_dbg_f(urb_dev(urb), "error: urb %p to small\n", urb);
428                 goto resubmit;
429         }
430
431         hdr = urb->transfer_buffer;
432         if (hdr->type != USB_INT_TYPE) {
433                 dev_dbg_f(urb_dev(urb), "error: urb %p wrong type\n", urb);
434                 goto resubmit;
435         }
436
437         switch (hdr->id) {
438         case USB_INT_ID_REGS:
439                 handle_regs_int(urb);
440                 break;
441         case USB_INT_ID_RETRY_FAILED:
442                 handle_retry_failed_int(urb);
443                 break;
444         default:
445                 dev_dbg_f(urb_dev(urb), "error: urb %p unknown id %x\n", urb,
446                         (unsigned int)hdr->id);
447                 goto resubmit;
448         }
449
450 resubmit:
451         r = usb_submit_urb(urb, GFP_ATOMIC);
452         if (r) {
453                 dev_dbg_f(urb_dev(urb), "resubmit urb %p\n", urb);
454                 goto kfree;
455         }
456         return;
457 kfree:
458         kfree(urb->transfer_buffer);
459 }
460
461 static inline int int_urb_interval(struct usb_device *udev)
462 {
463         switch (udev->speed) {
464         case USB_SPEED_HIGH:
465                 return 4;
466         case USB_SPEED_LOW:
467                 return 10;
468         case USB_SPEED_FULL:
469         default:
470                 return 1;
471         }
472 }
473
474 static inline int usb_int_enabled(struct zd_usb *usb)
475 {
476         unsigned long flags;
477         struct zd_usb_interrupt *intr = &usb->intr;
478         struct urb *urb;
479
480         spin_lock_irqsave(&intr->lock, flags);
481         urb = intr->urb;
482         spin_unlock_irqrestore(&intr->lock, flags);
483         return urb != NULL;
484 }
485
486 int zd_usb_enable_int(struct zd_usb *usb)
487 {
488         int r;
489         struct usb_device *udev;
490         struct zd_usb_interrupt *intr = &usb->intr;
491         void *transfer_buffer = NULL;
492         struct urb *urb;
493
494         dev_dbg_f(zd_usb_dev(usb), "\n");
495
496         urb = usb_alloc_urb(0, GFP_NOFS);
497         if (!urb) {
498                 r = -ENOMEM;
499                 goto out;
500         }
501
502         ZD_ASSERT(!irqs_disabled());
503         spin_lock_irq(&intr->lock);
504         if (intr->urb) {
505                 spin_unlock_irq(&intr->lock);
506                 r = 0;
507                 goto error_free_urb;
508         }
509         intr->urb = urb;
510         spin_unlock_irq(&intr->lock);
511
512         /* TODO: make it a DMA buffer */
513         r = -ENOMEM;
514         transfer_buffer = kmalloc(USB_MAX_EP_INT_BUFFER, GFP_NOFS);
515         if (!transfer_buffer) {
516                 dev_dbg_f(zd_usb_dev(usb),
517                         "couldn't allocate transfer_buffer\n");
518                 goto error_set_urb_null;
519         }
520
521         udev = zd_usb_to_usbdev(usb);
522         usb_fill_int_urb(urb, udev, usb_rcvintpipe(udev, EP_INT_IN),
523                          transfer_buffer, USB_MAX_EP_INT_BUFFER,
524                          int_urb_complete, usb,
525                          intr->interval);
526
527         dev_dbg_f(zd_usb_dev(usb), "submit urb %p\n", intr->urb);
528         r = usb_submit_urb(urb, GFP_NOFS);
529         if (r) {
530                 dev_dbg_f(zd_usb_dev(usb),
531                          "Couldn't submit urb. Error number %d\n", r);
532                 goto error;
533         }
534
535         return 0;
536 error:
537         kfree(transfer_buffer);
538 error_set_urb_null:
539         spin_lock_irq(&intr->lock);
540         intr->urb = NULL;
541         spin_unlock_irq(&intr->lock);
542 error_free_urb:
543         usb_free_urb(urb);
544 out:
545         return r;
546 }
547
548 void zd_usb_disable_int(struct zd_usb *usb)
549 {
550         unsigned long flags;
551         struct zd_usb_interrupt *intr = &usb->intr;
552         struct urb *urb;
553
554         spin_lock_irqsave(&intr->lock, flags);
555         urb = intr->urb;
556         if (!urb) {
557                 spin_unlock_irqrestore(&intr->lock, flags);
558                 return;
559         }
560         intr->urb = NULL;
561         spin_unlock_irqrestore(&intr->lock, flags);
562
563         usb_kill_urb(urb);
564         dev_dbg_f(zd_usb_dev(usb), "urb %p killed\n", urb);
565         usb_free_urb(urb);
566 }
567
568 static void handle_rx_packet(struct zd_usb *usb, const u8 *buffer,
569                              unsigned int length)
570 {
571         int i;
572         struct zd_mac *mac = zd_usb_to_mac(usb);
573         const struct rx_length_info *length_info;
574
575         if (length < sizeof(struct rx_length_info)) {
576                 /* It's not a complete packet anyhow. */
577                 return;
578         }
579         length_info = (struct rx_length_info *)
580                 (buffer + length - sizeof(struct rx_length_info));
581
582         /* It might be that three frames are merged into a single URB
583          * transaction. We have to check for the length info tag.
584          *
585          * While testing we discovered that length_info might be unaligned,
586          * because if USB transactions are merged, the last packet will not
587          * be padded. Unaligned access might also happen if the length_info
588          * structure is not present.
589          */
590         if (get_unaligned(&length_info->tag) == cpu_to_le16(RX_LENGTH_INFO_TAG))
591         {
592                 unsigned int l, k, n;
593                 for (i = 0, l = 0;; i++) {
594                         k = le16_to_cpu(get_unaligned(&length_info->length[i]));
595                         n = l+k;
596                         if (n > length)
597                                 return;
598                         zd_mac_rx(mac, buffer+l, k);
599                         if (i >= 2)
600                                 return;
601                         l = (n+3) & ~3;
602                 }
603         } else {
604                 zd_mac_rx(mac, buffer, length);
605         }
606 }
607
608 static void rx_urb_complete(struct urb *urb)
609 {
610         struct zd_usb *usb;
611         struct zd_usb_rx *rx;
612         const u8 *buffer;
613         unsigned int length;
614
615         switch (urb->status) {
616         case 0:
617                 break;
618         case -ESHUTDOWN:
619         case -EINVAL:
620         case -ENODEV:
621         case -ENOENT:
622         case -ECONNRESET:
623         case -EPIPE:
624                 return;
625         default:
626                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
627                 goto resubmit;
628         }
629
630         buffer = urb->transfer_buffer;
631         length = urb->actual_length;
632         usb = urb->context;
633         rx = &usb->rx;
634
635         if (length%rx->usb_packet_size > rx->usb_packet_size-4) {
636                 /* If there is an old first fragment, we don't care. */
637                 dev_dbg_f(urb_dev(urb), "*** first fragment ***\n");
638                 ZD_ASSERT(length <= ARRAY_SIZE(rx->fragment));
639                 spin_lock(&rx->lock);
640                 memcpy(rx->fragment, buffer, length);
641                 rx->fragment_length = length;
642                 spin_unlock(&rx->lock);
643                 goto resubmit;
644         }
645
646         spin_lock(&rx->lock);
647         if (rx->fragment_length > 0) {
648                 /* We are on a second fragment, we believe */
649                 ZD_ASSERT(length + rx->fragment_length <=
650                           ARRAY_SIZE(rx->fragment));
651                 dev_dbg_f(urb_dev(urb), "*** second fragment ***\n");
652                 memcpy(rx->fragment+rx->fragment_length, buffer, length);
653                 handle_rx_packet(usb, rx->fragment,
654                                  rx->fragment_length + length);
655                 rx->fragment_length = 0;
656                 spin_unlock(&rx->lock);
657         } else {
658                 spin_unlock(&rx->lock);
659                 handle_rx_packet(usb, buffer, length);
660         }
661
662 resubmit:
663         usb_submit_urb(urb, GFP_ATOMIC);
664 }
665
666 static struct urb *alloc_urb(struct zd_usb *usb)
667 {
668         struct usb_device *udev = zd_usb_to_usbdev(usb);
669         struct urb *urb;
670         void *buffer;
671
672         urb = usb_alloc_urb(0, GFP_NOFS);
673         if (!urb)
674                 return NULL;
675         buffer = usb_buffer_alloc(udev, USB_MAX_RX_SIZE, GFP_NOFS,
676                                   &urb->transfer_dma);
677         if (!buffer) {
678                 usb_free_urb(urb);
679                 return NULL;
680         }
681
682         usb_fill_bulk_urb(urb, udev, usb_rcvbulkpipe(udev, EP_DATA_IN),
683                           buffer, USB_MAX_RX_SIZE,
684                           rx_urb_complete, usb);
685         urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
686
687         return urb;
688 }
689
690 static void free_urb(struct urb *urb)
691 {
692         if (!urb)
693                 return;
694         usb_buffer_free(urb->dev, urb->transfer_buffer_length,
695                         urb->transfer_buffer, urb->transfer_dma);
696         usb_free_urb(urb);
697 }
698
699 int zd_usb_enable_rx(struct zd_usb *usb)
700 {
701         int i, r;
702         struct zd_usb_rx *rx = &usb->rx;
703         struct urb **urbs;
704
705         dev_dbg_f(zd_usb_dev(usb), "\n");
706
707         r = -ENOMEM;
708         urbs = kcalloc(URBS_COUNT, sizeof(struct urb *), GFP_NOFS);
709         if (!urbs)
710                 goto error;
711         for (i = 0; i < URBS_COUNT; i++) {
712                 urbs[i] = alloc_urb(usb);
713                 if (!urbs[i])
714                         goto error;
715         }
716
717         ZD_ASSERT(!irqs_disabled());
718         spin_lock_irq(&rx->lock);
719         if (rx->urbs) {
720                 spin_unlock_irq(&rx->lock);
721                 r = 0;
722                 goto error;
723         }
724         rx->urbs = urbs;
725         rx->urbs_count = URBS_COUNT;
726         spin_unlock_irq(&rx->lock);
727
728         for (i = 0; i < URBS_COUNT; i++) {
729                 r = usb_submit_urb(urbs[i], GFP_NOFS);
730                 if (r)
731                         goto error_submit;
732         }
733
734         return 0;
735 error_submit:
736         for (i = 0; i < URBS_COUNT; i++) {
737                 usb_kill_urb(urbs[i]);
738         }
739         spin_lock_irq(&rx->lock);
740         rx->urbs = NULL;
741         rx->urbs_count = 0;
742         spin_unlock_irq(&rx->lock);
743 error:
744         if (urbs) {
745                 for (i = 0; i < URBS_COUNT; i++)
746                         free_urb(urbs[i]);
747         }
748         return r;
749 }
750
751 void zd_usb_disable_rx(struct zd_usb *usb)
752 {
753         int i;
754         unsigned long flags;
755         struct urb **urbs;
756         unsigned int count;
757         struct zd_usb_rx *rx = &usb->rx;
758
759         spin_lock_irqsave(&rx->lock, flags);
760         urbs = rx->urbs;
761         count = rx->urbs_count;
762         spin_unlock_irqrestore(&rx->lock, flags);
763         if (!urbs)
764                 return;
765
766         for (i = 0; i < count; i++) {
767                 usb_kill_urb(urbs[i]);
768                 free_urb(urbs[i]);
769         }
770         kfree(urbs);
771
772         spin_lock_irqsave(&rx->lock, flags);
773         rx->urbs = NULL;
774         rx->urbs_count = 0;
775         spin_unlock_irqrestore(&rx->lock, flags);
776 }
777
778 static void tx_urb_complete(struct urb *urb)
779 {
780         int r;
781
782         switch (urb->status) {
783         case 0:
784                 break;
785         case -ESHUTDOWN:
786         case -EINVAL:
787         case -ENODEV:
788         case -ENOENT:
789         case -ECONNRESET:
790         case -EPIPE:
791                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
792                 break;
793         default:
794                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
795                 goto resubmit;
796         }
797 free_urb:
798         usb_buffer_free(urb->dev, urb->transfer_buffer_length,
799                         urb->transfer_buffer, urb->transfer_dma);
800         usb_free_urb(urb);
801         return;
802 resubmit:
803         r = usb_submit_urb(urb, GFP_ATOMIC);
804         if (r) {
805                 dev_dbg_f(urb_dev(urb), "error resubmit urb %p %d\n", urb, r);
806                 goto free_urb;
807         }
808 }
809
810 /* Puts the frame on the USB endpoint. It doesn't wait for
811  * completion. The frame must contain the control set.
812  */
813 int zd_usb_tx(struct zd_usb *usb, const u8 *frame, unsigned int length)
814 {
815         int r;
816         struct usb_device *udev = zd_usb_to_usbdev(usb);
817         struct urb *urb;
818         void *buffer;
819
820         urb = usb_alloc_urb(0, GFP_ATOMIC);
821         if (!urb) {
822                 r = -ENOMEM;
823                 goto out;
824         }
825
826         buffer = usb_buffer_alloc(zd_usb_to_usbdev(usb), length, GFP_ATOMIC,
827                                   &urb->transfer_dma);
828         if (!buffer) {
829                 r = -ENOMEM;
830                 goto error_free_urb;
831         }
832         memcpy(buffer, frame, length);
833
834         usb_fill_bulk_urb(urb, udev, usb_sndbulkpipe(udev, EP_DATA_OUT),
835                           buffer, length, tx_urb_complete, NULL);
836         urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
837
838         r = usb_submit_urb(urb, GFP_ATOMIC);
839         if (r)
840                 goto error;
841         return 0;
842 error:
843         usb_buffer_free(zd_usb_to_usbdev(usb), length, buffer,
844                         urb->transfer_dma);
845 error_free_urb:
846         usb_free_urb(urb);
847 out:
848         return r;
849 }
850
851 static inline void init_usb_interrupt(struct zd_usb *usb)
852 {
853         struct zd_usb_interrupt *intr = &usb->intr;
854
855         spin_lock_init(&intr->lock);
856         intr->interval = int_urb_interval(zd_usb_to_usbdev(usb));
857         init_completion(&intr->read_regs.completion);
858         intr->read_regs.cr_int_addr = cpu_to_le16(usb_addr(usb, CR_INTERRUPT));
859 }
860
861 static inline void init_usb_rx(struct zd_usb *usb)
862 {
863         struct zd_usb_rx *rx = &usb->rx;
864         spin_lock_init(&rx->lock);
865         if (interface_to_usbdev(usb->intf)->speed == USB_SPEED_HIGH) {
866                 rx->usb_packet_size = 512;
867         } else {
868                 rx->usb_packet_size = 64;
869         }
870         ZD_ASSERT(rx->fragment_length == 0);
871 }
872
873 static inline void init_usb_tx(struct zd_usb *usb)
874 {
875         /* FIXME: at this point we will allocate a fixed number of urb's for
876          * use in a cyclic scheme */
877 }
878
879 void zd_usb_init(struct zd_usb *usb, struct net_device *netdev,
880                  struct usb_interface *intf)
881 {
882         memset(usb, 0, sizeof(*usb));
883         usb->intf = usb_get_intf(intf);
884         usb_set_intfdata(usb->intf, netdev);
885         init_usb_interrupt(usb);
886         init_usb_tx(usb);
887         init_usb_rx(usb);
888 }
889
890 int zd_usb_init_hw(struct zd_usb *usb)
891 {
892         int r;
893         struct zd_chip *chip = zd_usb_to_chip(usb);
894
895         ZD_ASSERT(mutex_is_locked(&chip->mutex));
896         r = zd_ioread16_locked(chip, &usb->fw_base_offset,
897                         USB_REG((u16)FW_BASE_ADDR_OFFSET));
898         if (r)
899                 return r;
900         dev_dbg_f(zd_usb_dev(usb), "fw_base_offset: %#06hx\n",
901                  usb->fw_base_offset);
902
903         return 0;
904 }
905
906 void zd_usb_clear(struct zd_usb *usb)
907 {
908         usb_set_intfdata(usb->intf, NULL);
909         usb_put_intf(usb->intf);
910         ZD_MEMCLEAR(usb, sizeof(*usb));
911         /* FIXME: usb_interrupt, usb_tx, usb_rx? */
912 }
913
914 static const char *speed(enum usb_device_speed speed)
915 {
916         switch (speed) {
917         case USB_SPEED_LOW:
918                 return "low";
919         case USB_SPEED_FULL:
920                 return "full";
921         case USB_SPEED_HIGH:
922                 return "high";
923         default:
924                 return "unknown speed";
925         }
926 }
927
928 static int scnprint_id(struct usb_device *udev, char *buffer, size_t size)
929 {
930         return scnprintf(buffer, size, "%04hx:%04hx v%04hx %s",
931                 le16_to_cpu(udev->descriptor.idVendor),
932                 le16_to_cpu(udev->descriptor.idProduct),
933                 get_bcdDevice(udev),
934                 speed(udev->speed));
935 }
936
937 int zd_usb_scnprint_id(struct zd_usb *usb, char *buffer, size_t size)
938 {
939         struct usb_device *udev = interface_to_usbdev(usb->intf);
940         return scnprint_id(udev, buffer, size);
941 }
942
943 #ifdef DEBUG
944 static void print_id(struct usb_device *udev)
945 {
946         char buffer[40];
947
948         scnprint_id(udev, buffer, sizeof(buffer));
949         buffer[sizeof(buffer)-1] = 0;
950         dev_dbg_f(&udev->dev, "%s\n", buffer);
951 }
952 #else
953 #define print_id(udev) do { } while (0)
954 #endif
955
956 static int eject_installer(struct usb_interface *intf)
957 {
958         struct usb_device *udev = interface_to_usbdev(intf);
959         struct usb_host_interface *iface_desc = &intf->altsetting[0];
960         struct usb_endpoint_descriptor *endpoint;
961         unsigned char *cmd;
962         u8 bulk_out_ep;
963         int r;
964
965         /* Find bulk out endpoint */
966         endpoint = &iface_desc->endpoint[1].desc;
967         if ((endpoint->bEndpointAddress & USB_TYPE_MASK) == USB_DIR_OUT &&
968             (endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) ==
969             USB_ENDPOINT_XFER_BULK) {
970                 bulk_out_ep = endpoint->bEndpointAddress;
971         } else {
972                 dev_err(&udev->dev,
973                         "zd1211rw: Could not find bulk out endpoint\n");
974                 return -ENODEV;
975         }
976
977         cmd = kzalloc(31, GFP_KERNEL);
978         if (cmd == NULL)
979                 return -ENODEV;
980
981         /* USB bulk command block */
982         cmd[0] = 0x55;  /* bulk command signature */
983         cmd[1] = 0x53;  /* bulk command signature */
984         cmd[2] = 0x42;  /* bulk command signature */
985         cmd[3] = 0x43;  /* bulk command signature */
986         cmd[14] = 6;    /* command length */
987
988         cmd[15] = 0x1b; /* SCSI command: START STOP UNIT */
989         cmd[19] = 0x2;  /* eject disc */
990
991         dev_info(&udev->dev, "Ejecting virtual installer media...\n");
992         r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, bulk_out_ep),
993                 cmd, 31, NULL, 2000);
994         kfree(cmd);
995         if (r)
996                 return r;
997
998         /* At this point, the device disconnects and reconnects with the real
999          * ID numbers. */
1000
1001         usb_set_intfdata(intf, NULL);
1002         return 0;
1003 }
1004
1005 static int probe(struct usb_interface *intf, const struct usb_device_id *id)
1006 {
1007         int r;
1008         struct usb_device *udev = interface_to_usbdev(intf);
1009         struct net_device *netdev = NULL;
1010
1011         print_id(udev);
1012
1013         if (id->driver_info & DEVICE_INSTALLER)
1014                 return eject_installer(intf);
1015
1016         switch (udev->speed) {
1017         case USB_SPEED_LOW:
1018         case USB_SPEED_FULL:
1019         case USB_SPEED_HIGH:
1020                 break;
1021         default:
1022                 dev_dbg_f(&intf->dev, "Unknown USB speed\n");
1023                 r = -ENODEV;
1024                 goto error;
1025         }
1026
1027         netdev = zd_netdev_alloc(intf);
1028         if (netdev == NULL) {
1029                 r = -ENOMEM;
1030                 goto error;
1031         }
1032
1033         r = upload_firmware(udev, id->driver_info);
1034         if (r) {
1035                 dev_err(&intf->dev,
1036                        "couldn't load firmware. Error number %d\n", r);
1037                 goto error;
1038         }
1039
1040         r = usb_reset_configuration(udev);
1041         if (r) {
1042                 dev_dbg_f(&intf->dev,
1043                         "couldn't reset configuration. Error number %d\n", r);
1044                 goto error;
1045         }
1046
1047         /* At this point the interrupt endpoint is not generally enabled. We
1048          * save the USB bandwidth until the network device is opened. But
1049          * notify that the initialization of the MAC will require the
1050          * interrupts to be temporary enabled.
1051          */
1052         r = zd_mac_init_hw(zd_netdev_mac(netdev), id->driver_info);
1053         if (r) {
1054                 dev_dbg_f(&intf->dev,
1055                          "couldn't initialize mac. Error number %d\n", r);
1056                 goto error;
1057         }
1058
1059         r = register_netdev(netdev);
1060         if (r) {
1061                 dev_dbg_f(&intf->dev,
1062                          "couldn't register netdev. Error number %d\n", r);
1063                 goto error;
1064         }
1065
1066         dev_dbg_f(&intf->dev, "successful\n");
1067         dev_info(&intf->dev,"%s\n", netdev->name);
1068         return 0;
1069 error:
1070         usb_reset_device(interface_to_usbdev(intf));
1071         zd_netdev_free(netdev);
1072         return r;
1073 }
1074
1075 static void disconnect(struct usb_interface *intf)
1076 {
1077         struct net_device *netdev = zd_intf_to_netdev(intf);
1078         struct zd_mac *mac = zd_netdev_mac(netdev);
1079         struct zd_usb *usb = &mac->chip.usb;
1080
1081         /* Either something really bad happened, or we're just dealing with
1082          * a DEVICE_INSTALLER. */
1083         if (netdev == NULL)
1084                 return;
1085
1086         dev_dbg_f(zd_usb_dev(usb), "\n");
1087
1088         zd_netdev_disconnect(netdev);
1089
1090         /* Just in case something has gone wrong! */
1091         zd_usb_disable_rx(usb);
1092         zd_usb_disable_int(usb);
1093
1094         /* If the disconnect has been caused by a removal of the
1095          * driver module, the reset allows reloading of the driver. If the
1096          * reset will not be executed here, the upload of the firmware in the
1097          * probe function caused by the reloading of the driver will fail.
1098          */
1099         usb_reset_device(interface_to_usbdev(intf));
1100
1101         zd_netdev_free(netdev);
1102         dev_dbg(&intf->dev, "disconnected\n");
1103 }
1104
1105 static struct usb_driver driver = {
1106         .name           = "zd1211rw",
1107         .id_table       = usb_ids,
1108         .probe          = probe,
1109         .disconnect     = disconnect,
1110 };
1111
1112 struct workqueue_struct *zd_workqueue;
1113
1114 static int __init usb_init(void)
1115 {
1116         int r;
1117
1118         pr_debug("usb_init()\n");
1119
1120         zd_workqueue = create_singlethread_workqueue(driver.name);
1121         if (zd_workqueue == NULL) {
1122                 printk(KERN_ERR "%s: couldn't create workqueue\n", driver.name);
1123                 return -ENOMEM;
1124         }
1125
1126         r = usb_register(&driver);
1127         if (r) {
1128                 printk(KERN_ERR "usb_register() failed. Error number %d\n", r);
1129                 return r;
1130         }
1131
1132         pr_debug("zd1211rw initialized\n");
1133         return 0;
1134 }
1135
1136 static void __exit usb_exit(void)
1137 {
1138         pr_debug("usb_exit()\n");
1139         usb_deregister(&driver);
1140         destroy_workqueue(zd_workqueue);
1141 }
1142
1143 module_init(usb_init);
1144 module_exit(usb_exit);
1145
1146 static int usb_int_regs_length(unsigned int count)
1147 {
1148         return sizeof(struct usb_int_regs) + count * sizeof(struct reg_data);
1149 }
1150
1151 static void prepare_read_regs_int(struct zd_usb *usb)
1152 {
1153         struct zd_usb_interrupt *intr = &usb->intr;
1154
1155         spin_lock_irq(&intr->lock);
1156         intr->read_regs_enabled = 1;
1157         INIT_COMPLETION(intr->read_regs.completion);
1158         spin_unlock_irq(&intr->lock);
1159 }
1160
1161 static void disable_read_regs_int(struct zd_usb *usb)
1162 {
1163         struct zd_usb_interrupt *intr = &usb->intr;
1164
1165         spin_lock_irq(&intr->lock);
1166         intr->read_regs_enabled = 0;
1167         spin_unlock_irq(&intr->lock);
1168 }
1169
1170 static int get_results(struct zd_usb *usb, u16 *values,
1171                        struct usb_req_read_regs *req, unsigned int count)
1172 {
1173         int r;
1174         int i;
1175         struct zd_usb_interrupt *intr = &usb->intr;
1176         struct read_regs_int *rr = &intr->read_regs;
1177         struct usb_int_regs *regs = (struct usb_int_regs *)rr->buffer;
1178
1179         spin_lock_irq(&intr->lock);
1180
1181         r = -EIO;
1182         /* The created block size seems to be larger than expected.
1183          * However results appear to be correct.
1184          */
1185         if (rr->length < usb_int_regs_length(count)) {
1186                 dev_dbg_f(zd_usb_dev(usb),
1187                          "error: actual length %d less than expected %d\n",
1188                          rr->length, usb_int_regs_length(count));
1189                 goto error_unlock;
1190         }
1191         if (rr->length > sizeof(rr->buffer)) {
1192                 dev_dbg_f(zd_usb_dev(usb),
1193                          "error: actual length %d exceeds buffer size %zu\n",
1194                          rr->length, sizeof(rr->buffer));
1195                 goto error_unlock;
1196         }
1197
1198         for (i = 0; i < count; i++) {
1199                 struct reg_data *rd = &regs->regs[i];
1200                 if (rd->addr != req->addr[i]) {
1201                         dev_dbg_f(zd_usb_dev(usb),
1202                                  "rd[%d] addr %#06hx expected %#06hx\n", i,
1203                                  le16_to_cpu(rd->addr),
1204                                  le16_to_cpu(req->addr[i]));
1205                         goto error_unlock;
1206                 }
1207                 values[i] = le16_to_cpu(rd->value);
1208         }
1209
1210         r = 0;
1211 error_unlock:
1212         spin_unlock_irq(&intr->lock);
1213         return r;
1214 }
1215
1216 int zd_usb_ioread16v(struct zd_usb *usb, u16 *values,
1217                      const zd_addr_t *addresses, unsigned int count)
1218 {
1219         int r;
1220         int i, req_len, actual_req_len;
1221         struct usb_device *udev;
1222         struct usb_req_read_regs *req = NULL;
1223         unsigned long timeout;
1224
1225         if (count < 1) {
1226                 dev_dbg_f(zd_usb_dev(usb), "error: count is zero\n");
1227                 return -EINVAL;
1228         }
1229         if (count > USB_MAX_IOREAD16_COUNT) {
1230                 dev_dbg_f(zd_usb_dev(usb),
1231                          "error: count %u exceeds possible max %u\n",
1232                          count, USB_MAX_IOREAD16_COUNT);
1233                 return -EINVAL;
1234         }
1235         if (in_atomic()) {
1236                 dev_dbg_f(zd_usb_dev(usb),
1237                          "error: io in atomic context not supported\n");
1238                 return -EWOULDBLOCK;
1239         }
1240         if (!usb_int_enabled(usb)) {
1241                  dev_dbg_f(zd_usb_dev(usb),
1242                           "error: usb interrupt not enabled\n");
1243                 return -EWOULDBLOCK;
1244         }
1245
1246         req_len = sizeof(struct usb_req_read_regs) + count * sizeof(__le16);
1247         req = kmalloc(req_len, GFP_NOFS);
1248         if (!req)
1249                 return -ENOMEM;
1250         req->id = cpu_to_le16(USB_REQ_READ_REGS);
1251         for (i = 0; i < count; i++)
1252                 req->addr[i] = cpu_to_le16(usb_addr(usb, addresses[i]));
1253
1254         udev = zd_usb_to_usbdev(usb);
1255         prepare_read_regs_int(usb);
1256         r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, EP_REGS_OUT),
1257                          req, req_len, &actual_req_len, 1000 /* ms */);
1258         if (r) {
1259                 dev_dbg_f(zd_usb_dev(usb),
1260                         "error in usb_bulk_msg(). Error number %d\n", r);
1261                 goto error;
1262         }
1263         if (req_len != actual_req_len) {
1264                 dev_dbg_f(zd_usb_dev(usb), "error in usb_bulk_msg()\n"
1265                         " req_len %d != actual_req_len %d\n",
1266                         req_len, actual_req_len);
1267                 r = -EIO;
1268                 goto error;
1269         }
1270
1271         timeout = wait_for_completion_timeout(&usb->intr.read_regs.completion,
1272                                               msecs_to_jiffies(1000));
1273         if (!timeout) {
1274                 disable_read_regs_int(usb);
1275                 dev_dbg_f(zd_usb_dev(usb), "read timed out\n");
1276                 r = -ETIMEDOUT;
1277                 goto error;
1278         }
1279
1280         r = get_results(usb, values, req, count);
1281 error:
1282         kfree(req);
1283         return r;
1284 }
1285
1286 int zd_usb_iowrite16v(struct zd_usb *usb, const struct zd_ioreq16 *ioreqs,
1287                       unsigned int count)
1288 {
1289         int r;
1290         struct usb_device *udev;
1291         struct usb_req_write_regs *req = NULL;
1292         int i, req_len, actual_req_len;
1293
1294         if (count == 0)
1295                 return 0;
1296         if (count > USB_MAX_IOWRITE16_COUNT) {
1297                 dev_dbg_f(zd_usb_dev(usb),
1298                         "error: count %u exceeds possible max %u\n",
1299                         count, USB_MAX_IOWRITE16_COUNT);
1300                 return -EINVAL;
1301         }
1302         if (in_atomic()) {
1303                 dev_dbg_f(zd_usb_dev(usb),
1304                         "error: io in atomic context not supported\n");
1305                 return -EWOULDBLOCK;
1306         }
1307
1308         req_len = sizeof(struct usb_req_write_regs) +
1309                   count * sizeof(struct reg_data);
1310         req = kmalloc(req_len, GFP_NOFS);
1311         if (!req)
1312                 return -ENOMEM;
1313
1314         req->id = cpu_to_le16(USB_REQ_WRITE_REGS);
1315         for (i = 0; i < count; i++) {
1316                 struct reg_data *rw  = &req->reg_writes[i];
1317                 rw->addr = cpu_to_le16(usb_addr(usb, ioreqs[i].addr));
1318                 rw->value = cpu_to_le16(ioreqs[i].value);
1319         }
1320
1321         udev = zd_usb_to_usbdev(usb);
1322         r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, EP_REGS_OUT),
1323                          req, req_len, &actual_req_len, 1000 /* ms */);
1324         if (r) {
1325                 dev_dbg_f(zd_usb_dev(usb),
1326                         "error in usb_bulk_msg(). Error number %d\n", r);
1327                 goto error;
1328         }
1329         if (req_len != actual_req_len) {
1330                 dev_dbg_f(zd_usb_dev(usb),
1331                         "error in usb_bulk_msg()"
1332                         " req_len %d != actual_req_len %d\n",
1333                         req_len, actual_req_len);
1334                 r = -EIO;
1335                 goto error;
1336         }
1337
1338         /* FALL-THROUGH with r == 0 */
1339 error:
1340         kfree(req);
1341         return r;
1342 }
1343
1344 int zd_usb_rfwrite(struct zd_usb *usb, u32 value, u8 bits)
1345 {
1346         int r;
1347         struct usb_device *udev;
1348         struct usb_req_rfwrite *req = NULL;
1349         int i, req_len, actual_req_len;
1350         u16 bit_value_template;
1351
1352         if (in_atomic()) {
1353                 dev_dbg_f(zd_usb_dev(usb),
1354                         "error: io in atomic context not supported\n");
1355                 return -EWOULDBLOCK;
1356         }
1357         if (bits < USB_MIN_RFWRITE_BIT_COUNT) {
1358                 dev_dbg_f(zd_usb_dev(usb),
1359                         "error: bits %d are smaller than"
1360                         " USB_MIN_RFWRITE_BIT_COUNT %d\n",
1361                         bits, USB_MIN_RFWRITE_BIT_COUNT);
1362                 return -EINVAL;
1363         }
1364         if (bits > USB_MAX_RFWRITE_BIT_COUNT) {
1365                 dev_dbg_f(zd_usb_dev(usb),
1366                         "error: bits %d exceed USB_MAX_RFWRITE_BIT_COUNT %d\n",
1367                         bits, USB_MAX_RFWRITE_BIT_COUNT);
1368                 return -EINVAL;
1369         }
1370 #ifdef DEBUG
1371         if (value & (~0UL << bits)) {
1372                 dev_dbg_f(zd_usb_dev(usb),
1373                         "error: value %#09x has bits >= %d set\n",
1374                         value, bits);
1375                 return -EINVAL;
1376         }
1377 #endif /* DEBUG */
1378
1379         dev_dbg_f(zd_usb_dev(usb), "value %#09x bits %d\n", value, bits);
1380
1381         r = zd_usb_ioread16(usb, &bit_value_template, CR203);
1382         if (r) {
1383                 dev_dbg_f(zd_usb_dev(usb),
1384                         "error %d: Couldn't read CR203\n", r);
1385                 goto out;
1386         }
1387         bit_value_template &= ~(RF_IF_LE|RF_CLK|RF_DATA);
1388
1389         req_len = sizeof(struct usb_req_rfwrite) + bits * sizeof(__le16);
1390         req = kmalloc(req_len, GFP_NOFS);
1391         if (!req)
1392                 return -ENOMEM;
1393
1394         req->id = cpu_to_le16(USB_REQ_WRITE_RF);
1395         /* 1: 3683a, but not used in ZYDAS driver */
1396         req->value = cpu_to_le16(2);
1397         req->bits = cpu_to_le16(bits);
1398
1399         for (i = 0; i < bits; i++) {
1400                 u16 bv = bit_value_template;
1401                 if (value & (1 << (bits-1-i)))
1402                         bv |= RF_DATA;
1403                 req->bit_values[i] = cpu_to_le16(bv);
1404         }
1405
1406         udev = zd_usb_to_usbdev(usb);
1407         r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, EP_REGS_OUT),
1408                          req, req_len, &actual_req_len, 1000 /* ms */);
1409         if (r) {
1410                 dev_dbg_f(zd_usb_dev(usb),
1411                         "error in usb_bulk_msg(). Error number %d\n", r);
1412                 goto out;
1413         }
1414         if (req_len != actual_req_len) {
1415                 dev_dbg_f(zd_usb_dev(usb), "error in usb_bulk_msg()"
1416                         " req_len %d != actual_req_len %d\n",
1417                         req_len, actual_req_len);
1418                 r = -EIO;
1419                 goto out;
1420         }
1421
1422         /* FALL-THROUGH with r == 0 */
1423 out:
1424         kfree(req);
1425         return r;
1426 }