1 /*
2 * HWA Host Controller Driver
3 * Wire Adapter Control/Data Streaming Iface (WUSB1.0[8])
4 *
5 * Copyright (C) 2005-2006 Intel Corporation
6 * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License version
10 * 2 as published by the Free Software Foundation.
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., 51 Franklin Street, Fifth Floor, Boston, MA
20 * 02110-1301, USA.
21 *
22 *
23 * This driver implements a USB Host Controller (struct usb_hcd) for a
24 * Wireless USB Host Controller based on the Wireless USB 1.0
25 * Host-Wire-Adapter specification (in layman terms, a USB-dongle that
26 * implements a Wireless USB host).
27 *
28 * Check out the Design-overview.txt file in the source documentation
29 * for other details on the implementation.
30 *
31 * Main blocks:
32 *
33 * driver glue with the driver API, workqueue daemon
34 *
35 * lc RC instance life cycle management (create, destroy...)
36 *
37 * hcd glue with the USB API Host Controller Interface API.
38 *
39 * nep Notification EndPoint management: collect notifications
40 * and queue them with the workqueue daemon.
41 *
42 * Handle notifications as coming from the NEP. Sends them
43 * off others to their respective modules (eg: connect,
44 * disconnect and reset go to devconnect).
45 *
46 * rpipe Remote Pipe management; rpipe is what we use to write
47 * to an endpoint on a WUSB device that is connected to a
48 * HWA RC.
49 *
50 * xfer Transfer management -- this is all the code that gets a
51 * buffer and pushes it to a device (or viceversa). *
52 *
53 * Some day a lot of this code will be shared between this driver and
54 * the drivers for DWA (xfer, rpipe).
55 *
56 * All starts at driver.c:hwahc_probe(), when one of this guys is
57 * connected. hwahc_disconnect() stops it.
58 *
59 * During operation, the main driver is devices connecting or
60 * disconnecting. They cause the HWA RC to send notifications into
61 * nep.c:hwahc_nep_cb() that will dispatch them to
62 * notif.c:wa_notif_dispatch(). From there they will fan to cause
63 * device connects, disconnects, etc.
64 *
65 * Note much of the activity is difficult to follow. For example a
66 * device connect goes to devconnect, which will cause the "fake" root
67 * hub port to show a connect and stop there. Then hub_wq will notice
68 * and call into the rh.c:hwahc_rc_port_reset() code to authenticate
69 * the device (and this might require user intervention) and enable
70 * the port.
71 *
72 * We also have a timer workqueue going from devconnect.c that
73 * schedules in hwahc_devconnect_create().
74 *
75 * The rest of the traffic is in the usual entry points of a USB HCD,
76 * which are hooked up in driver.c:hwahc_rc_driver, and defined in
77 * hcd.c.
78 */
79
80 #ifndef __HWAHC_INTERNAL_H__
81 #define __HWAHC_INTERNAL_H__
82
83 #include <linux/completion.h>
84 #include <linux/usb.h>
85 #include <linux/mutex.h>
86 #include <linux/spinlock.h>
87 #include <linux/uwb.h>
88 #include <linux/usb/wusb.h>
89 #include <linux/usb/wusb-wa.h>
90
91 struct wusbhc;
92 struct wahc;
93 extern void wa_urb_enqueue_run(struct work_struct *ws);
94 extern void wa_process_errored_transfers_run(struct work_struct *ws);
95
96 /**
97 * RPipe instance
98 *
99 * @descr's fields are kept in LE, as we need to send it back and
100 * forth.
101 *
102 * @wa is referenced when set
103 *
104 * @segs_available is the number of requests segments that still can
105 * be submitted to the controller without overloading
106 * it. It is initialized to descr->wRequests when
107 * aiming.
108 *
109 * A rpipe supports a max of descr->wRequests at the same time; before
110 * submitting seg_lock has to be taken. If segs_avail > 0, then we can
111 * submit; if not, we have to queue them.
112 */
113 struct wa_rpipe {
114 struct kref refcnt;
115 struct usb_rpipe_descriptor descr;
116 struct usb_host_endpoint *ep;
117 struct wahc *wa;
118 spinlock_t seg_lock;
119 struct list_head seg_list;
120 struct list_head list_node;
121 atomic_t segs_available;
122 u8 buffer[1]; /* For reads/writes on USB */
123 };
124
125
126 enum wa_dti_state {
127 WA_DTI_TRANSFER_RESULT_PENDING,
128 WA_DTI_ISOC_PACKET_STATUS_PENDING,
129 WA_DTI_BUF_IN_DATA_PENDING
130 };
131
132 enum wa_quirks {
133 /*
134 * The Alereon HWA expects the data frames in isochronous transfer
135 * requests to be concatenated and not sent as separate packets.
136 */
137 WUSB_QUIRK_ALEREON_HWA_CONCAT_ISOC = 0x01,
138 /*
139 * The Alereon HWA can be instructed to not send transfer notifications
140 * as an optimization.
141 */
142 WUSB_QUIRK_ALEREON_HWA_DISABLE_XFER_NOTIFICATIONS = 0x02,
143 };
144
145 enum wa_vendor_specific_requests {
146 WA_REQ_ALEREON_DISABLE_XFER_NOTIFICATIONS = 0x4C,
147 WA_REQ_ALEREON_FEATURE_SET = 0x01,
148 WA_REQ_ALEREON_FEATURE_CLEAR = 0x00,
149 };
150
151 #define WA_MAX_BUF_IN_URBS 4
152 /**
153 * Instance of a HWA Host Controller
154 *
155 * Except where a more specific lock/mutex applies or atomic, all
156 * fields protected by @mutex.
157 *
158 * @wa_descr Can be accessed without locking because it is in
159 * the same area where the device descriptors were
160 * read, so it is guaranteed to exist unmodified while
161 * the device exists.
162 *
163 * Endianess has been converted to CPU's.
164 *
165 * @nep_* can be accessed without locking as its processing is
166 * serialized; we submit a NEP URB and it comes to
167 * hwahc_nep_cb(), which won't issue another URB until it is
168 * done processing it.
169 *
170 * @xfer_list:
171 *
172 * List of active transfers to verify existence from a xfer id
173 * gotten from the xfer result message. Can't use urb->list because
174 * it goes by endpoint, and we don't know the endpoint at the time
175 * when we get the xfer result message. We can't really rely on the
176 * pointer (will have to change for 64 bits) as the xfer id is 32 bits.
177 *
178 * @xfer_delayed_list: List of transfers that need to be started
179 * (with a workqueue, because they were
180 * submitted from an atomic context).
181 *
182 * FIXME: this needs to be layered up: a wusbhc layer (for sharing
183 * commonalities with WHCI), a wa layer (for sharing
184 * commonalities with DWA-RC).
185 */
186 struct wahc {
187 struct usb_device *usb_dev;
188 struct usb_interface *usb_iface;
189
190 /* HC to deliver notifications */
191 union {
192 struct wusbhc *wusb;
193 struct dwahc *dwa;
194 };
195
196 const struct usb_endpoint_descriptor *dto_epd, *dti_epd;
197 const struct usb_wa_descriptor *wa_descr;
198
199 struct urb *nep_urb; /* Notification EndPoint [lockless] */
200 struct edc nep_edc;
201 void *nep_buffer;
202 size_t nep_buffer_size;
203
204 atomic_t notifs_queued;
205
206 u16 rpipes;
207 unsigned long *rpipe_bm; /* rpipe usage bitmap */
208 struct list_head rpipe_delayed_list; /* delayed RPIPES. */
209 spinlock_t rpipe_lock; /* protect rpipe_bm and delayed list */
210 struct mutex rpipe_mutex; /* assigning resources to endpoints */
211
212 /*
213 * dti_state is used to track the state of the dti_urb. When dti_state
214 * is WA_DTI_ISOC_PACKET_STATUS_PENDING, dti_isoc_xfer_in_progress and
215 * dti_isoc_xfer_seg identify which xfer the incoming isoc packet
216 * status refers to.
217 */
218 enum wa_dti_state dti_state;
219 u32 dti_isoc_xfer_in_progress;
220 u8 dti_isoc_xfer_seg;
221 struct urb *dti_urb; /* URB for reading xfer results */
222 /* URBs for reading data in */
223 struct urb buf_in_urbs[WA_MAX_BUF_IN_URBS];
224 int active_buf_in_urbs; /* number of buf_in_urbs active. */
225 struct edc dti_edc; /* DTI error density counter */
226 void *dti_buf;
227 size_t dti_buf_size;
228
229 unsigned long dto_in_use; /* protect dto endoint serialization */
230
231 s32 status; /* For reading status */
232
233 struct list_head xfer_list;
234 struct list_head xfer_delayed_list;
235 struct list_head xfer_errored_list;
236 /*
237 * lock for the above xfer lists. Can be taken while a xfer->lock is
238 * held but not in the reverse order.
239 */
240 spinlock_t xfer_list_lock;
241 struct work_struct xfer_enqueue_work;
242 struct work_struct xfer_error_work;
243 atomic_t xfer_id_count;
244
245 kernel_ulong_t quirks;
246 };
247
248
249 extern int wa_create(struct wahc *wa, struct usb_interface *iface,
250 kernel_ulong_t);
251 extern void __wa_destroy(struct wahc *wa);
252 extern int wa_dti_start(struct wahc *wa);
253 void wa_reset_all(struct wahc *wa);
254
255
256 /* Miscellaneous constants */
257 enum {
258 /** Max number of EPROTO errors we tolerate on the NEP in a
259 * period of time */
260 HWAHC_EPROTO_MAX = 16,
261 /** Period of time for EPROTO errors (in jiffies) */
262 HWAHC_EPROTO_PERIOD = 4 * HZ,
263 };
264
265
266 /* Notification endpoint handling */
267 extern int wa_nep_create(struct wahc *, struct usb_interface *);
268 extern void wa_nep_destroy(struct wahc *);
269
wa_nep_arm(struct wahc * wa,gfp_t gfp_mask)270 static inline int wa_nep_arm(struct wahc *wa, gfp_t gfp_mask)
271 {
272 struct urb *urb = wa->nep_urb;
273 urb->transfer_buffer = wa->nep_buffer;
274 urb->transfer_buffer_length = wa->nep_buffer_size;
275 return usb_submit_urb(urb, gfp_mask);
276 }
277
wa_nep_disarm(struct wahc * wa)278 static inline void wa_nep_disarm(struct wahc *wa)
279 {
280 usb_kill_urb(wa->nep_urb);
281 }
282
283
284 /* RPipes */
wa_rpipe_init(struct wahc * wa)285 static inline void wa_rpipe_init(struct wahc *wa)
286 {
287 INIT_LIST_HEAD(&wa->rpipe_delayed_list);
288 spin_lock_init(&wa->rpipe_lock);
289 mutex_init(&wa->rpipe_mutex);
290 }
291
wa_init(struct wahc * wa)292 static inline void wa_init(struct wahc *wa)
293 {
294 int index;
295
296 edc_init(&wa->nep_edc);
297 atomic_set(&wa->notifs_queued, 0);
298 wa->dti_state = WA_DTI_TRANSFER_RESULT_PENDING;
299 wa_rpipe_init(wa);
300 edc_init(&wa->dti_edc);
301 INIT_LIST_HEAD(&wa->xfer_list);
302 INIT_LIST_HEAD(&wa->xfer_delayed_list);
303 INIT_LIST_HEAD(&wa->xfer_errored_list);
304 spin_lock_init(&wa->xfer_list_lock);
305 INIT_WORK(&wa->xfer_enqueue_work, wa_urb_enqueue_run);
306 INIT_WORK(&wa->xfer_error_work, wa_process_errored_transfers_run);
307 wa->dto_in_use = 0;
308 atomic_set(&wa->xfer_id_count, 1);
309 /* init the buf in URBs */
310 for (index = 0; index < WA_MAX_BUF_IN_URBS; ++index)
311 usb_init_urb(&(wa->buf_in_urbs[index]));
312 wa->active_buf_in_urbs = 0;
313 }
314
315 /**
316 * Destroy a pipe (when refcount drops to zero)
317 *
318 * Assumes it has been moved to the "QUIESCING" state.
319 */
320 struct wa_xfer;
321 extern void rpipe_destroy(struct kref *_rpipe);
322 static inline
__rpipe_get(struct wa_rpipe * rpipe)323 void __rpipe_get(struct wa_rpipe *rpipe)
324 {
325 kref_get(&rpipe->refcnt);
326 }
327 extern int rpipe_get_by_ep(struct wahc *, struct usb_host_endpoint *,
328 struct urb *, gfp_t);
rpipe_put(struct wa_rpipe * rpipe)329 static inline void rpipe_put(struct wa_rpipe *rpipe)
330 {
331 kref_put(&rpipe->refcnt, rpipe_destroy);
332
333 }
334 extern void rpipe_ep_disable(struct wahc *, struct usb_host_endpoint *);
335 extern void rpipe_clear_feature_stalled(struct wahc *,
336 struct usb_host_endpoint *);
337 extern int wa_rpipes_create(struct wahc *);
338 extern void wa_rpipes_destroy(struct wahc *);
rpipe_avail_dec(struct wa_rpipe * rpipe)339 static inline void rpipe_avail_dec(struct wa_rpipe *rpipe)
340 {
341 atomic_dec(&rpipe->segs_available);
342 }
343
344 /**
345 * Returns true if the rpipe is ready to submit more segments.
346 */
rpipe_avail_inc(struct wa_rpipe * rpipe)347 static inline int rpipe_avail_inc(struct wa_rpipe *rpipe)
348 {
349 return atomic_inc_return(&rpipe->segs_available) > 0
350 && !list_empty(&rpipe->seg_list);
351 }
352
353
354 /* Transferring data */
355 extern int wa_urb_enqueue(struct wahc *, struct usb_host_endpoint *,
356 struct urb *, gfp_t);
357 extern int wa_urb_dequeue(struct wahc *, struct urb *, int);
358 extern void wa_handle_notif_xfer(struct wahc *, struct wa_notif_hdr *);
359
360
361 /* Misc
362 *
363 * FIXME: Refcounting for the actual @hwahc object is not correct; I
364 * mean, this should be refcounting on the HCD underneath, but
365 * it is not. In any case, the semantics for HCD refcounting
366 * are *weird*...on refcount reaching zero it just frees
367 * it...no RC specific function is called...unless I miss
368 * something.
369 *
370 * FIXME: has to go away in favour of a 'struct' hcd based solution
371 */
wa_get(struct wahc * wa)372 static inline struct wahc *wa_get(struct wahc *wa)
373 {
374 usb_get_intf(wa->usb_iface);
375 return wa;
376 }
377
wa_put(struct wahc * wa)378 static inline void wa_put(struct wahc *wa)
379 {
380 usb_put_intf(wa->usb_iface);
381 }
382
383
__wa_feature(struct wahc * wa,unsigned op,u16 feature)384 static inline int __wa_feature(struct wahc *wa, unsigned op, u16 feature)
385 {
386 return usb_control_msg(wa->usb_dev, usb_sndctrlpipe(wa->usb_dev, 0),
387 op ? USB_REQ_SET_FEATURE : USB_REQ_CLEAR_FEATURE,
388 USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
389 feature,
390 wa->usb_iface->cur_altsetting->desc.bInterfaceNumber,
391 NULL, 0, USB_CTRL_SET_TIMEOUT);
392 }
393
394
__wa_set_feature(struct wahc * wa,u16 feature)395 static inline int __wa_set_feature(struct wahc *wa, u16 feature)
396 {
397 return __wa_feature(wa, 1, feature);
398 }
399
400
__wa_clear_feature(struct wahc * wa,u16 feature)401 static inline int __wa_clear_feature(struct wahc *wa, u16 feature)
402 {
403 return __wa_feature(wa, 0, feature);
404 }
405
406
407 /**
408 * Return the status of a Wire Adapter
409 *
410 * @wa: Wire Adapter instance
411 * @returns < 0 errno code on error, or status bitmap as described
412 * in WUSB1.0[8.3.1.6].
413 *
414 * NOTE: need malloc, some arches don't take USB from the stack
415 */
416 static inline
__wa_get_status(struct wahc * wa)417 s32 __wa_get_status(struct wahc *wa)
418 {
419 s32 result;
420 result = usb_control_msg(
421 wa->usb_dev, usb_rcvctrlpipe(wa->usb_dev, 0),
422 USB_REQ_GET_STATUS,
423 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
424 0, wa->usb_iface->cur_altsetting->desc.bInterfaceNumber,
425 &wa->status, sizeof(wa->status), USB_CTRL_GET_TIMEOUT);
426 if (result >= 0)
427 result = wa->status;
428 return result;
429 }
430
431
432 /**
433 * Waits until the Wire Adapter's status matches @mask/@value
434 *
435 * @wa: Wire Adapter instance.
436 * @returns < 0 errno code on error, otherwise status.
437 *
438 * Loop until the WAs status matches the mask and value (status & mask
439 * == value). Timeout if it doesn't happen.
440 *
441 * FIXME: is there an official specification on how long status
442 * changes can take?
443 */
__wa_wait_status(struct wahc * wa,u32 mask,u32 value)444 static inline s32 __wa_wait_status(struct wahc *wa, u32 mask, u32 value)
445 {
446 s32 result;
447 unsigned loops = 10;
448 do {
449 msleep(50);
450 result = __wa_get_status(wa);
451 if ((result & mask) == value)
452 break;
453 if (loops-- == 0) {
454 result = -ETIMEDOUT;
455 break;
456 }
457 } while (result >= 0);
458 return result;
459 }
460
461
462 /** Command @hwahc to stop, @returns 0 if ok, < 0 errno code on error */
__wa_stop(struct wahc * wa)463 static inline int __wa_stop(struct wahc *wa)
464 {
465 int result;
466 struct device *dev = &wa->usb_iface->dev;
467
468 result = __wa_clear_feature(wa, WA_ENABLE);
469 if (result < 0 && result != -ENODEV) {
470 dev_err(dev, "error commanding HC to stop: %d\n", result);
471 goto out;
472 }
473 result = __wa_wait_status(wa, WA_ENABLE, 0);
474 if (result < 0 && result != -ENODEV)
475 dev_err(dev, "error waiting for HC to stop: %d\n", result);
476 out:
477 return 0;
478 }
479
480
481 #endif /* #ifndef __HWAHC_INTERNAL_H__ */
482