rt2x00: Put 802.11 data on 4 byte boundary
[sfrench/cifs-2.6.git] / drivers / net / wireless / rt2x00 / rt2x00usb.c
1 /*
2         Copyright (C) 2004 - 2007 rt2x00 SourceForge Project
3         <http://rt2x00.serialmonkey.com>
4
5         This program is free software; you can redistribute it and/or modify
6         it under the terms of the GNU General Public License as published by
7         the Free Software Foundation; either version 2 of the License, or
8         (at your option) any later version.
9
10         This program is distributed in the hope that it will be useful,
11         but WITHOUT ANY WARRANTY; without even the implied warranty of
12         MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13         GNU General Public License for more details.
14
15         You should have received a copy of the GNU General Public License
16         along with this program; if not, write to the
17         Free Software Foundation, Inc.,
18         59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
19  */
20
21 /*
22         Module: rt2x00usb
23         Abstract: rt2x00 generic usb device routines.
24  */
25
26 /*
27  * Set enviroment defines for rt2x00.h
28  */
29 #define DRV_NAME "rt2x00usb"
30
31 #include <linux/kernel.h>
32 #include <linux/module.h>
33 #include <linux/usb.h>
34
35 #include "rt2x00.h"
36 #include "rt2x00usb.h"
37
38 /*
39  * Interfacing with the HW.
40  */
41 int rt2x00usb_vendor_request(const struct rt2x00_dev *rt2x00dev,
42                              const u8 request, const u8 requesttype,
43                              const u16 offset, const u16 value,
44                              void *buffer, const u16 buffer_length,
45                              const int timeout)
46 {
47         struct usb_device *usb_dev =
48             interface_to_usbdev(rt2x00dev_usb(rt2x00dev));
49         int status;
50         unsigned int i;
51         unsigned int pipe =
52             (requesttype == USB_VENDOR_REQUEST_IN) ?
53             usb_rcvctrlpipe(usb_dev, 0) : usb_sndctrlpipe(usb_dev, 0);
54
55         for (i = 0; i < REGISTER_BUSY_COUNT; i++) {
56                 status = usb_control_msg(usb_dev, pipe, request, requesttype,
57                                          value, offset, buffer, buffer_length,
58                                          timeout);
59                 if (status >= 0)
60                         return 0;
61
62                 /*
63                  * Check for errors
64                  * -ENODEV: Device has disappeared, no point continuing.
65                  * All other errors: Try again.
66                  */
67                 else if (status == -ENODEV)
68                         break;
69         }
70
71         ERROR(rt2x00dev,
72               "Vendor Request 0x%02x failed for offset 0x%04x with error %d.\n",
73               request, offset, status);
74
75         return status;
76 }
77 EXPORT_SYMBOL_GPL(rt2x00usb_vendor_request);
78
79 int rt2x00usb_vendor_request_buff(const struct rt2x00_dev *rt2x00dev,
80                                   const u8 request, const u8 requesttype,
81                                   const u16 offset, void *buffer,
82                                   const u16 buffer_length, const int timeout)
83 {
84         int status;
85
86         /*
87          * Check for Cache availability.
88          */
89         if (unlikely(!rt2x00dev->csr_cache || buffer_length > CSR_CACHE_SIZE)) {
90                 ERROR(rt2x00dev, "CSR cache not available.\n");
91                 return -ENOMEM;
92         }
93
94         if (requesttype == USB_VENDOR_REQUEST_OUT)
95                 memcpy(rt2x00dev->csr_cache, buffer, buffer_length);
96
97         status = rt2x00usb_vendor_request(rt2x00dev, request, requesttype,
98                                           offset, 0, rt2x00dev->csr_cache,
99                                           buffer_length, timeout);
100
101         if (!status && requesttype == USB_VENDOR_REQUEST_IN)
102                 memcpy(buffer, rt2x00dev->csr_cache, buffer_length);
103
104         return status;
105 }
106 EXPORT_SYMBOL_GPL(rt2x00usb_vendor_request_buff);
107
108 /*
109  * TX data handlers.
110  */
111 static void rt2x00usb_interrupt_txdone(struct urb *urb)
112 {
113         struct data_entry *entry = (struct data_entry *)urb->context;
114         struct data_ring *ring = entry->ring;
115         struct rt2x00_dev *rt2x00dev = ring->rt2x00dev;
116         struct data_desc *txd = (struct data_desc *)entry->skb->data;
117         u32 word;
118         int tx_status;
119
120         if (!test_bit(DEVICE_ENABLED_RADIO, &rt2x00dev->flags) ||
121             !__test_and_clear_bit(ENTRY_OWNER_NIC, &entry->flags))
122                 return;
123
124         rt2x00_desc_read(txd, 0, &word);
125
126         /*
127          * Remove the descriptor data from the buffer.
128          */
129         skb_pull(entry->skb, ring->desc_size);
130
131         /*
132          * Obtain the status about this packet.
133          */
134         tx_status = !urb->status ? TX_SUCCESS : TX_FAIL_RETRY;
135
136         rt2x00lib_txdone(entry, tx_status, 0);
137
138         /*
139          * Make this entry available for reuse.
140          */
141         entry->flags = 0;
142         rt2x00_ring_index_done_inc(entry->ring);
143
144         /*
145          * If the data ring was full before the txdone handler
146          * we must make sure the packet queue in the mac80211 stack
147          * is reenabled when the txdone handler has finished.
148          */
149         if (!rt2x00_ring_full(ring))
150                 ieee80211_wake_queue(rt2x00dev->hw,
151                                      entry->tx_status.control.queue);
152 }
153
154 int rt2x00usb_write_tx_data(struct rt2x00_dev *rt2x00dev,
155                             struct data_ring *ring, struct sk_buff *skb,
156                             struct ieee80211_tx_control *control)
157 {
158         struct usb_device *usb_dev =
159             interface_to_usbdev(rt2x00dev_usb(rt2x00dev));
160         struct data_entry *entry = rt2x00_get_data_entry(ring);
161         int pipe = usb_sndbulkpipe(usb_dev, 1);
162         u32 length;
163
164         if (rt2x00_ring_full(ring)) {
165                 ieee80211_stop_queue(rt2x00dev->hw, control->queue);
166                 return -EINVAL;
167         }
168
169         if (test_bit(ENTRY_OWNER_NIC, &entry->flags)) {
170                 ERROR(rt2x00dev,
171                       "Arrived at non-free entry in the non-full queue %d.\n"
172                       "Please file bug report to %s.\n",
173                       control->queue, DRV_PROJECT);
174                 ieee80211_stop_queue(rt2x00dev->hw, control->queue);
175                 return -EINVAL;
176         }
177
178         /*
179          * Add the descriptor in front of the skb.
180          */
181         skb_push(skb, ring->desc_size);
182         memset(skb->data, 0, ring->desc_size);
183
184         rt2x00lib_write_tx_desc(rt2x00dev, (struct data_desc *)skb->data,
185                                 (struct ieee80211_hdr *)(skb->data +
186                                                          ring->desc_size),
187                                 skb->len - ring->desc_size, control);
188         memcpy(&entry->tx_status.control, control, sizeof(*control));
189         entry->skb = skb;
190
191         /*
192          * USB devices cannot blindly pass the skb->len as the
193          * length of the data to usb_fill_bulk_urb. Pass the skb
194          * to the driver to determine what the length should be.
195          */
196         length = rt2x00dev->ops->lib->get_tx_data_len(rt2x00dev, skb);
197
198         /*
199          * Initialize URB and send the frame to the device.
200          */
201         __set_bit(ENTRY_OWNER_NIC, &entry->flags);
202         usb_fill_bulk_urb(entry->priv, usb_dev, pipe,
203                           skb->data, length, rt2x00usb_interrupt_txdone, entry);
204         usb_submit_urb(entry->priv, GFP_ATOMIC);
205
206         rt2x00_ring_index_inc(ring);
207
208         if (rt2x00_ring_full(ring))
209                 ieee80211_stop_queue(rt2x00dev->hw, control->queue);
210
211         return 0;
212 }
213 EXPORT_SYMBOL_GPL(rt2x00usb_write_tx_data);
214
215 /*
216  * RX data handlers.
217  */
218 static void rt2x00usb_interrupt_rxdone(struct urb *urb)
219 {
220         struct data_entry *entry = (struct data_entry *)urb->context;
221         struct data_ring *ring = entry->ring;
222         struct rt2x00_dev *rt2x00dev = ring->rt2x00dev;
223         struct sk_buff *skb;
224         struct ieee80211_hdr *hdr;
225         struct rxdata_entry_desc desc;
226         int header_size;
227         int frame_size;
228
229         if (!test_bit(DEVICE_ENABLED_RADIO, &rt2x00dev->flags) ||
230             !test_and_clear_bit(ENTRY_OWNER_NIC, &entry->flags))
231                 return;
232
233         /*
234          * Check if the received data is simply too small
235          * to be actually valid, or if the urb is signaling
236          * a problem.
237          */
238         if (urb->actual_length < entry->ring->desc_size || urb->status)
239                 goto skip_entry;
240
241         memset(&desc, 0x00, sizeof(desc));
242         rt2x00dev->ops->lib->fill_rxdone(entry, &desc);
243
244         /*
245          * Allocate a new sk buffer to replace the current one.
246          * If allocation fails, we should drop the current frame
247          * so we can recycle the existing sk buffer for the new frame.
248          */
249         frame_size = entry->ring->data_size + entry->ring->desc_size;
250         skb = dev_alloc_skb(frame_size + NET_IP_ALIGN);
251         if (!skb)
252                 goto skip_entry;
253
254         skb_reserve(skb, NET_IP_ALIGN);
255         skb_put(skb, frame_size);
256
257         /*
258          * The data behind the ieee80211 header must be
259          * aligned on a 4 byte boundary.
260          * After that trim the entire buffer down to only
261          * contain the valid frame data excluding the device
262          * descriptor.
263          */
264         hdr = (struct ieee80211_hdr *)entry->skb->data;
265         header_size =
266             ieee80211_get_hdrlen(le16_to_cpu(hdr->frame_control));
267
268         if (header_size % 4 == 0) {
269                 skb_push(entry->skb, 2);
270                 memmove(entry->skb->data, entry->skb->data + 2, skb->len - 2);
271         }
272         skb_trim(entry->skb, desc.size);
273
274         /*
275          * Send the frame to rt2x00lib for further processing.
276          */
277         rt2x00lib_rxdone(entry, entry->skb, &desc);
278
279         /*
280          * Replace current entry's skb with the newly allocated one,
281          * and reinitialize the urb.
282          */
283         entry->skb = skb;
284         urb->transfer_buffer = entry->skb->data;
285         urb->transfer_buffer_length = entry->skb->len;
286
287 skip_entry:
288         if (test_bit(DEVICE_ENABLED_RADIO, &ring->rt2x00dev->flags)) {
289                 __set_bit(ENTRY_OWNER_NIC, &entry->flags);
290                 usb_submit_urb(urb, GFP_ATOMIC);
291         }
292
293         rt2x00_ring_index_inc(ring);
294 }
295
296 /*
297  * Radio handlers
298  */
299 void rt2x00usb_enable_radio(struct rt2x00_dev *rt2x00dev)
300 {
301         struct usb_device *usb_dev =
302             interface_to_usbdev(rt2x00dev_usb(rt2x00dev));
303         struct data_ring *ring;
304         struct data_entry *entry;
305         unsigned int i;
306
307         /*
308          * Initialize the TX rings
309          */
310         txringall_for_each(rt2x00dev, ring) {
311                 for (i = 0; i < ring->stats.limit; i++)
312                         ring->entry[i].flags = 0;
313
314                 rt2x00_ring_index_clear(ring);
315         }
316
317         /*
318          * Initialize and start the RX ring.
319          */
320         rt2x00_ring_index_clear(rt2x00dev->rx);
321
322         for (i = 0; i < rt2x00dev->rx->stats.limit; i++) {
323                 entry = &rt2x00dev->rx->entry[i];
324
325                 usb_fill_bulk_urb(entry->priv, usb_dev,
326                                   usb_rcvbulkpipe(usb_dev, 1),
327                                   entry->skb->data, entry->skb->len,
328                                   rt2x00usb_interrupt_rxdone, entry);
329
330                 __set_bit(ENTRY_OWNER_NIC, &entry->flags);
331                 usb_submit_urb(entry->priv, GFP_ATOMIC);
332         }
333 }
334 EXPORT_SYMBOL_GPL(rt2x00usb_enable_radio);
335
336 void rt2x00usb_disable_radio(struct rt2x00_dev *rt2x00dev)
337 {
338         struct data_ring *ring;
339         unsigned int i;
340
341         rt2x00usb_vendor_request_sw(rt2x00dev, USB_RX_CONTROL, 0x0000, 0x0000,
342                                     REGISTER_TIMEOUT);
343
344         /*
345          * Cancel all rings.
346          */
347         ring_for_each(rt2x00dev, ring) {
348                 for (i = 0; i < ring->stats.limit; i++)
349                         usb_kill_urb(ring->entry[i].priv);
350         }
351 }
352 EXPORT_SYMBOL_GPL(rt2x00usb_disable_radio);
353
354 /*
355  * Device initialization handlers.
356  */
357 static int rt2x00usb_alloc_urb(struct rt2x00_dev *rt2x00dev,
358                                struct data_ring *ring)
359 {
360         unsigned int i;
361
362         /*
363          * Allocate the URB's
364          */
365         for (i = 0; i < ring->stats.limit; i++) {
366                 ring->entry[i].priv = usb_alloc_urb(0, GFP_KERNEL);
367                 if (!ring->entry[i].priv)
368                         return -ENOMEM;
369         }
370
371         return 0;
372 }
373
374 static void rt2x00usb_free_urb(struct rt2x00_dev *rt2x00dev,
375                                struct data_ring *ring)
376 {
377         unsigned int i;
378
379         if (!ring->entry)
380                 return;
381
382         for (i = 0; i < ring->stats.limit; i++) {
383                 usb_kill_urb(ring->entry[i].priv);
384                 usb_free_urb(ring->entry[i].priv);
385                 if (ring->entry[i].skb)
386                         kfree_skb(ring->entry[i].skb);
387         }
388 }
389
390 int rt2x00usb_initialize(struct rt2x00_dev *rt2x00dev)
391 {
392         struct data_ring *ring;
393         struct sk_buff *skb;
394         unsigned int entry_size;
395         unsigned int i;
396         int status;
397
398         /*
399          * Allocate DMA
400          */
401         ring_for_each(rt2x00dev, ring) {
402                 status = rt2x00usb_alloc_urb(rt2x00dev, ring);
403                 if (status)
404                         goto exit;
405         }
406
407         /*
408          * For the RX ring, skb's should be allocated.
409          */
410         entry_size = rt2x00dev->rx->data_size + rt2x00dev->rx->desc_size;
411         for (i = 0; i < rt2x00dev->rx->stats.limit; i++) {
412                 skb = dev_alloc_skb(NET_IP_ALIGN + entry_size);
413                 if (!skb)
414                         goto exit;
415
416                 skb_reserve(skb, NET_IP_ALIGN);
417                 skb_put(skb, entry_size);
418
419                 rt2x00dev->rx->entry[i].skb = skb;
420         }
421
422         return 0;
423
424 exit:
425         rt2x00usb_uninitialize(rt2x00dev);
426
427         return status;
428 }
429 EXPORT_SYMBOL_GPL(rt2x00usb_initialize);
430
431 void rt2x00usb_uninitialize(struct rt2x00_dev *rt2x00dev)
432 {
433         struct data_ring *ring;
434
435         ring_for_each(rt2x00dev, ring)
436                 rt2x00usb_free_urb(rt2x00dev, ring);
437 }
438 EXPORT_SYMBOL_GPL(rt2x00usb_uninitialize);
439
440 /*
441  * USB driver handlers.
442  */
443 static void rt2x00usb_free_reg(struct rt2x00_dev *rt2x00dev)
444 {
445         kfree(rt2x00dev->rf);
446         rt2x00dev->rf = NULL;
447
448         kfree(rt2x00dev->eeprom);
449         rt2x00dev->eeprom = NULL;
450
451         kfree(rt2x00dev->csr_cache);
452         rt2x00dev->csr_cache = NULL;
453 }
454
455 static int rt2x00usb_alloc_reg(struct rt2x00_dev *rt2x00dev)
456 {
457         rt2x00dev->csr_cache = kzalloc(CSR_CACHE_SIZE, GFP_KERNEL);
458         if (!rt2x00dev->csr_cache)
459                 goto exit;
460
461         rt2x00dev->eeprom = kzalloc(rt2x00dev->ops->eeprom_size, GFP_KERNEL);
462         if (!rt2x00dev->eeprom)
463                 goto exit;
464
465         rt2x00dev->rf = kzalloc(rt2x00dev->ops->rf_size, GFP_KERNEL);
466         if (!rt2x00dev->rf)
467                 goto exit;
468
469         return 0;
470
471 exit:
472         ERROR_PROBE("Failed to allocate registers.\n");
473
474         rt2x00usb_free_reg(rt2x00dev);
475
476         return -ENOMEM;
477 }
478
479 int rt2x00usb_probe(struct usb_interface *usb_intf,
480                     const struct usb_device_id *id)
481 {
482         struct usb_device *usb_dev = interface_to_usbdev(usb_intf);
483         struct rt2x00_ops *ops = (struct rt2x00_ops *)id->driver_info;
484         struct ieee80211_hw *hw;
485         struct rt2x00_dev *rt2x00dev;
486         int retval;
487
488         usb_dev = usb_get_dev(usb_dev);
489
490         hw = ieee80211_alloc_hw(sizeof(struct rt2x00_dev), ops->hw);
491         if (!hw) {
492                 ERROR_PROBE("Failed to allocate hardware.\n");
493                 retval = -ENOMEM;
494                 goto exit_put_device;
495         }
496
497         usb_set_intfdata(usb_intf, hw);
498
499         rt2x00dev = hw->priv;
500         rt2x00dev->dev = usb_intf;
501         rt2x00dev->ops = ops;
502         rt2x00dev->hw = hw;
503
504         rt2x00dev->usb_maxpacket =
505             usb_maxpacket(usb_dev, usb_sndbulkpipe(usb_dev, 1), 1);
506         if (!rt2x00dev->usb_maxpacket)
507                 rt2x00dev->usb_maxpacket = 1;
508
509         retval = rt2x00usb_alloc_reg(rt2x00dev);
510         if (retval)
511                 goto exit_free_device;
512
513         retval = rt2x00lib_probe_dev(rt2x00dev);
514         if (retval)
515                 goto exit_free_reg;
516
517         return 0;
518
519 exit_free_reg:
520         rt2x00usb_free_reg(rt2x00dev);
521
522 exit_free_device:
523         ieee80211_free_hw(hw);
524
525 exit_put_device:
526         usb_put_dev(usb_dev);
527
528         usb_set_intfdata(usb_intf, NULL);
529
530         return retval;
531 }
532 EXPORT_SYMBOL_GPL(rt2x00usb_probe);
533
534 void rt2x00usb_disconnect(struct usb_interface *usb_intf)
535 {
536         struct ieee80211_hw *hw = usb_get_intfdata(usb_intf);
537         struct rt2x00_dev *rt2x00dev = hw->priv;
538
539         /*
540          * Free all allocated data.
541          */
542         rt2x00lib_remove_dev(rt2x00dev);
543         rt2x00usb_free_reg(rt2x00dev);
544         ieee80211_free_hw(hw);
545
546         /*
547          * Free the USB device data.
548          */
549         usb_set_intfdata(usb_intf, NULL);
550         usb_put_dev(interface_to_usbdev(usb_intf));
551 }
552 EXPORT_SYMBOL_GPL(rt2x00usb_disconnect);
553
554 #ifdef CONFIG_PM
555 int rt2x00usb_suspend(struct usb_interface *usb_intf, pm_message_t state)
556 {
557         struct ieee80211_hw *hw = usb_get_intfdata(usb_intf);
558         struct rt2x00_dev *rt2x00dev = hw->priv;
559         int retval;
560
561         retval = rt2x00lib_suspend(rt2x00dev, state);
562         if (retval)
563                 return retval;
564
565         rt2x00usb_free_reg(rt2x00dev);
566
567         /*
568          * Decrease usbdev refcount.
569          */
570         usb_put_dev(interface_to_usbdev(usb_intf));
571
572         return 0;
573 }
574 EXPORT_SYMBOL_GPL(rt2x00usb_suspend);
575
576 int rt2x00usb_resume(struct usb_interface *usb_intf)
577 {
578         struct ieee80211_hw *hw = usb_get_intfdata(usb_intf);
579         struct rt2x00_dev *rt2x00dev = hw->priv;
580         int retval;
581
582         usb_get_dev(interface_to_usbdev(usb_intf));
583
584         retval = rt2x00usb_alloc_reg(rt2x00dev);
585         if (retval)
586                 return retval;
587
588         retval = rt2x00lib_resume(rt2x00dev);
589         if (retval)
590                 goto exit_free_reg;
591
592         return 0;
593
594 exit_free_reg:
595         rt2x00usb_free_reg(rt2x00dev);
596
597         return retval;
598 }
599 EXPORT_SYMBOL_GPL(rt2x00usb_resume);
600 #endif /* CONFIG_PM */
601
602 /*
603  * rt2x00pci module information.
604  */
605 MODULE_AUTHOR(DRV_PROJECT);
606 MODULE_VERSION(DRV_VERSION);
607 MODULE_DESCRIPTION("rt2x00 library");
608 MODULE_LICENSE("GPL");