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1/*
2 * epautoconf.c -- endpoint autoconfiguration for usb gadget drivers
3 *
4 * Copyright (C) 2004 David Brownell
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 *
20 */
21
22#include <linux/kernel.h>
23#include <linux/init.h>
24#include <linux/types.h>
25#include <linux/device.h>
26
27#include <linux/ctype.h>
28#include <linux/string.h>
29
30#include <linux/usb/ch9.h>
31#include <linux/usb/gadget.h>
32
33#include "gadget_chips.h"
34
35
36/* we must assign addresses for configurable endpoints (like net2280) */
37static unsigned epnum;
38
39// #define MANY_ENDPOINTS
40#ifdef MANY_ENDPOINTS
41/* more than 15 configurable endpoints */
42static unsigned in_epnum;
43#endif
44
45
46/*
47 * This should work with endpoints from controller drivers sharing the
48 * same endpoint naming convention. By example:
49 *
50 * - ep1, ep2, ... address is fixed, not direction or type
51 * - ep1in, ep2out, ... address and direction are fixed, not type
52 * - ep1-bulk, ep2-bulk, ... address and type are fixed, not direction
53 * - ep1in-bulk, ep2out-iso, ... all three are fixed
54 * - ep-* ... no functionality restrictions
55 *
56 * Type suffixes are "-bulk", "-iso", or "-int". Numbers are decimal.
57 * Less common restrictions are implied by gadget_is_*().
58 *
59 * NOTE: each endpoint is unidirectional, as specified by its USB
60 * descriptor; and isn't specific to a configuration or altsetting.
61 */
62static int
63ep_matches (
64 struct usb_gadget *gadget,
65 struct usb_ep *ep,
66 struct usb_endpoint_descriptor *desc,
67 struct usb_ss_ep_comp_descriptor *ep_comp
68)
69{
70 u8 type;
71 const char *tmp;
72 u16 max;
73
74 int num_req_streams = 0;
75
76 /* endpoint already claimed? */
77 if (NULL != ep->driver_data)
78 return 0;
79
80 /* only support ep0 for portable CONTROL traffic */
81 type = desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK;
82 if (USB_ENDPOINT_XFER_CONTROL == type)
83 return 0;
84
85 /* some other naming convention */
86 if ('e' != ep->name[0])
87 return 0;
88
89 /* type-restriction: "-iso", "-bulk", or "-int".
90 * direction-restriction: "in", "out".
91 */
92 if ('-' != ep->name[2]) {
93 tmp = strrchr (ep->name, '-');
94 if (tmp) {
95 switch (type) {
96 case USB_ENDPOINT_XFER_INT:
97 /* bulk endpoints handle interrupt transfers,
98 * except the toggle-quirky iso-synch kind
99 */
100 if ('s' == tmp[2]) // == "-iso"
101 return 0;
102 /* for now, avoid PXA "interrupt-in";
103 * it's documented as never using DATA1.
104 */
105 if (gadget_is_pxa (gadget)
106 && 'i' == tmp [1])
107 return 0;
108 break;
109 case USB_ENDPOINT_XFER_BULK:
110 if ('b' != tmp[1]) // != "-bulk"
111 return 0;
112 break;
113 case USB_ENDPOINT_XFER_ISOC:
114 if ('s' != tmp[2]) // != "-iso"
115 return 0;
116 }
117 } else {
118 tmp = ep->name + strlen (ep->name);
119 }
120
121 /* direction-restriction: "..in-..", "out-.." */
122 tmp--;
123 if (!isdigit (*tmp)) {
124 if (desc->bEndpointAddress & USB_DIR_IN) {
125 if ('n' != *tmp)
126 return 0;
127 } else {
128 if ('t' != *tmp)
129 return 0;
130 }
131 }
132 }
133
134 /*
135 * Get the number of required streams from the EP companion
136 * descriptor and see if the EP matches it
137 */
138 if (usb_endpoint_xfer_bulk(desc)) {
139 if (ep_comp) {
140 num_req_streams = ep_comp->bmAttributes & 0x1f;
141 if (num_req_streams > ep->max_streams)
142 return 0;
143 /* Update the ep_comp descriptor if needed */
144 if (num_req_streams != ep->max_streams)
145 ep_comp->bmAttributes = ep->max_streams;
146 }
147
148 }
149
150 /*
151 * If the protocol driver hasn't yet decided on wMaxPacketSize
152 * and wants to know the maximum possible, provide the info.
153 */
154 if (desc->wMaxPacketSize == 0)
155 desc->wMaxPacketSize = cpu_to_le16(ep->maxpacket);
156
157 /* endpoint maxpacket size is an input parameter, except for bulk
158 * where it's an output parameter representing the full speed limit.
159 * the usb spec fixes high speed bulk maxpacket at 512 bytes.
160 */
161 max = 0x7ff & le16_to_cpu(desc->wMaxPacketSize);
162 switch (type) {
163 case USB_ENDPOINT_XFER_INT:
164 /* INT: limit 64 bytes full speed, 1024 high/super speed */
165 if (!gadget->is_dualspeed && max > 64)
166 return 0;
167 /* FALLTHROUGH */
168
169 case USB_ENDPOINT_XFER_ISOC:
170 /* ISO: limit 1023 bytes full speed, 1024 high/super speed */
171 if (ep->maxpacket < max)
172 return 0;
173 if (!gadget->is_dualspeed && max > 1023)
174 return 0;
175
176 /* BOTH: "high bandwidth" works only at high speed */
177 if ((desc->wMaxPacketSize & cpu_to_le16(3<<11))) {
178 if (!gadget->is_dualspeed)
179 return 0;
180 /* configure your hardware with enough buffering!! */
181 }
182 break;
183 }
184
185 /* MATCH!! */
186
187 /* report address */
188 desc->bEndpointAddress &= USB_DIR_IN;
189 if (isdigit (ep->name [2])) {
190 u8 num = simple_strtoul (&ep->name [2], NULL, 10);
191 desc->bEndpointAddress |= num;
192#ifdef MANY_ENDPOINTS
193 } else if (desc->bEndpointAddress & USB_DIR_IN) {
194 if (++in_epnum > 15)
195 return 0;
196 desc->bEndpointAddress = USB_DIR_IN | in_epnum;
197#endif
198 } else {
199 if (++epnum > 15)
200 return 0;
201 desc->bEndpointAddress |= epnum;
202 }
203
204 /* report (variable) full speed bulk maxpacket */
205 if ((USB_ENDPOINT_XFER_BULK == type) && !ep_comp) {
206 int size = ep->maxpacket;
207
208 /* min() doesn't work on bitfields with gcc-3.5 */
209 if (size > 64)
210 size = 64;
211 desc->wMaxPacketSize = cpu_to_le16(size);
212 }
213 ep->address = desc->bEndpointAddress;
214 return 1;
215}
216
217static struct usb_ep *
218find_ep (struct usb_gadget *gadget, const char *name)
219{
220 struct usb_ep *ep;
221
222 list_for_each_entry (ep, &gadget->ep_list, ep_list) {
223 if (0 == strcmp (ep->name, name))
224 return ep;
225 }
226 return NULL;
227}
228
229/**
230 * usb_ep_autoconfig_ss() - choose an endpoint matching the ep
231 * descriptor and ep companion descriptor
232 * @gadget: The device to which the endpoint must belong.
233 * @desc: Endpoint descriptor, with endpoint direction and transfer mode
234 * initialized. For periodic transfers, the maximum packet
235 * size must also be initialized. This is modified on
236 * success.
237 * @ep_comp: Endpoint companion descriptor, with the required
238 * number of streams. Will be modified when the chosen EP
239 * supports a different number of streams.
240 *
241 * This routine replaces the usb_ep_autoconfig when needed
242 * superspeed enhancments. If such enhancemnets are required,
243 * the FD should call usb_ep_autoconfig_ss directly and provide
244 * the additional ep_comp parameter.
245 *
246 * By choosing an endpoint to use with the specified descriptor,
247 * this routine simplifies writing gadget drivers that work with
248 * multiple USB device controllers. The endpoint would be
249 * passed later to usb_ep_enable(), along with some descriptor.
250 *
251 * That second descriptor won't always be the same as the first one.
252 * For example, isochronous endpoints can be autoconfigured for high
253 * bandwidth, and then used in several lower bandwidth altsettings.
254 * Also, high and full speed descriptors will be different.
255 *
256 * Be sure to examine and test the results of autoconfiguration
257 * on your hardware. This code may not make the best choices
258 * about how to use the USB controller, and it can't know all
259 * the restrictions that may apply. Some combinations of driver
260 * and hardware won't be able to autoconfigure.
261 *
262 * On success, this returns an un-claimed usb_ep, and modifies the endpoint
263 * descriptor bEndpointAddress. For bulk endpoints, the wMaxPacket value
264 * is initialized as if the endpoint were used at full speed and
265 * the bmAttribute field in the ep companion descriptor is
266 * updated with the assigned number of streams if it is
267 * different from the original value. To prevent the endpoint
268 * from being returned by a later autoconfig call, claim it by
269 * assigning ep->driver_data to some non-null value.
270 *
271 * On failure, this returns a null endpoint descriptor.
272 */
273struct usb_ep *usb_ep_autoconfig_ss(
274 struct usb_gadget *gadget,
275 struct usb_endpoint_descriptor *desc,
276 struct usb_ss_ep_comp_descriptor *ep_comp
277)
278{
279 struct usb_ep *ep;
280 u8 type;
281
282 type = desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK;
283
284 /* First, apply chip-specific "best usage" knowledge.
285 * This might make a good usb_gadget_ops hook ...
286 */
287 if (gadget_is_net2280 (gadget) && type == USB_ENDPOINT_XFER_INT) {
288 /* ep-e, ep-f are PIO with only 64 byte fifos */
289 ep = find_ep (gadget, "ep-e");
290 if (ep && ep_matches(gadget, ep, desc, ep_comp))
291 return ep;
292 ep = find_ep (gadget, "ep-f");
293 if (ep && ep_matches(gadget, ep, desc, ep_comp))
294 return ep;
295
296 } else if (gadget_is_goku (gadget)) {
297 if (USB_ENDPOINT_XFER_INT == type) {
298 /* single buffering is enough */
299 ep = find_ep(gadget, "ep3-bulk");
300 if (ep && ep_matches(gadget, ep, desc, ep_comp))
301 return ep;
302 } else if (USB_ENDPOINT_XFER_BULK == type
303 && (USB_DIR_IN & desc->bEndpointAddress)) {
304 /* DMA may be available */
305 ep = find_ep(gadget, "ep2-bulk");
306 if (ep && ep_matches(gadget, ep, desc,
307 ep_comp))
308 return ep;
309 }
310
311#ifdef CONFIG_BLACKFIN
312 } else if (gadget_is_musbhdrc(gadget)) {
313 if ((USB_ENDPOINT_XFER_BULK == type) ||
314 (USB_ENDPOINT_XFER_ISOC == type)) {
315 if (USB_DIR_IN & desc->bEndpointAddress)
316 ep = find_ep (gadget, "ep5in");
317 else
318 ep = find_ep (gadget, "ep6out");
319 } else if (USB_ENDPOINT_XFER_INT == type) {
320 if (USB_DIR_IN & desc->bEndpointAddress)
321 ep = find_ep(gadget, "ep1in");
322 else
323 ep = find_ep(gadget, "ep2out");
324 } else
325 ep = NULL;
326 if (ep && ep_matches(gadget, ep, desc, ep_comp))
327 return ep;
328#endif
329 }
330
331 /* Second, look at endpoints until an unclaimed one looks usable */
332 list_for_each_entry (ep, &gadget->ep_list, ep_list) {
333 if (ep_matches(gadget, ep, desc, ep_comp))
334 return ep;
335 }
336
337 /* Fail */
338 return NULL;
339}
340
341/**
342 * usb_ep_autoconfig() - choose an endpoint matching the
343 * descriptor
344 * @gadget: The device to which the endpoint must belong.
345 * @desc: Endpoint descriptor, with endpoint direction and transfer mode
346 * initialized. For periodic transfers, the maximum packet
347 * size must also be initialized. This is modified on success.
348 *
349 * By choosing an endpoint to use with the specified descriptor, this
350 * routine simplifies writing gadget drivers that work with multiple
351 * USB device controllers. The endpoint would be passed later to
352 * usb_ep_enable(), along with some descriptor.
353 *
354 * That second descriptor won't always be the same as the first one.
355 * For example, isochronous endpoints can be autoconfigured for high
356 * bandwidth, and then used in several lower bandwidth altsettings.
357 * Also, high and full speed descriptors will be different.
358 *
359 * Be sure to examine and test the results of autoconfiguration on your
360 * hardware. This code may not make the best choices about how to use the
361 * USB controller, and it can't know all the restrictions that may apply.
362 * Some combinations of driver and hardware won't be able to autoconfigure.
363 *
364 * On success, this returns an un-claimed usb_ep, and modifies the endpoint
365 * descriptor bEndpointAddress. For bulk endpoints, the wMaxPacket value
366 * is initialized as if the endpoint were used at full speed. To prevent
367 * the endpoint from being returned by a later autoconfig call, claim it
368 * by assigning ep->driver_data to some non-null value.
369 *
370 * On failure, this returns a null endpoint descriptor.
371 */
372struct usb_ep *usb_ep_autoconfig(
373 struct usb_gadget *gadget,
374 struct usb_endpoint_descriptor *desc
375)
376{
377 return usb_ep_autoconfig_ss(gadget, desc, NULL);
378}
379
380
381/**
382 * usb_ep_autoconfig_reset - reset endpoint autoconfig state
383 * @gadget: device for which autoconfig state will be reset
384 *
385 * Use this for devices where one configuration may need to assign
386 * endpoint resources very differently from the next one. It clears
387 * state such as ep->driver_data and the record of assigned endpoints
388 * used by usb_ep_autoconfig().
389 */
390void usb_ep_autoconfig_reset (struct usb_gadget *gadget)
391{
392 struct usb_ep *ep;
393
394 list_for_each_entry (ep, &gadget->ep_list, ep_list) {
395 ep->driver_data = NULL;
396 }
397#ifdef MANY_ENDPOINTS
398 in_epnum = 0;
399#endif
400 epnum = 0;
401}
402
1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * epautoconf.c -- endpoint autoconfiguration for usb gadget drivers
4 *
5 * Copyright (C) 2004 David Brownell
6 */
7
8#include <linux/kernel.h>
9#include <linux/module.h>
10#include <linux/types.h>
11#include <linux/device.h>
12
13#include <linux/ctype.h>
14#include <linux/string.h>
15
16#include <linux/usb/ch9.h>
17#include <linux/usb/gadget.h>
18
19/**
20 * usb_ep_autoconfig_ss() - choose an endpoint matching the ep
21 * descriptor and ep companion descriptor
22 * @gadget: The device to which the endpoint must belong.
23 * @desc: Endpoint descriptor, with endpoint direction and transfer mode
24 * initialized. For periodic transfers, the maximum packet
25 * size must also be initialized. This is modified on
26 * success.
27 * @ep_comp: Endpoint companion descriptor, with the required
28 * number of streams. Will be modified when the chosen EP
29 * supports a different number of streams.
30 *
31 * This routine replaces the usb_ep_autoconfig when needed
32 * superspeed enhancments. If such enhancemnets are required,
33 * the FD should call usb_ep_autoconfig_ss directly and provide
34 * the additional ep_comp parameter.
35 *
36 * By choosing an endpoint to use with the specified descriptor,
37 * this routine simplifies writing gadget drivers that work with
38 * multiple USB device controllers. The endpoint would be
39 * passed later to usb_ep_enable(), along with some descriptor.
40 *
41 * That second descriptor won't always be the same as the first one.
42 * For example, isochronous endpoints can be autoconfigured for high
43 * bandwidth, and then used in several lower bandwidth altsettings.
44 * Also, high and full speed descriptors will be different.
45 *
46 * Be sure to examine and test the results of autoconfiguration
47 * on your hardware. This code may not make the best choices
48 * about how to use the USB controller, and it can't know all
49 * the restrictions that may apply. Some combinations of driver
50 * and hardware won't be able to autoconfigure.
51 *
52 * On success, this returns an claimed usb_ep, and modifies the endpoint
53 * descriptor bEndpointAddress. For bulk endpoints, the wMaxPacket value
54 * is initialized as if the endpoint were used at full speed and
55 * the bmAttribute field in the ep companion descriptor is
56 * updated with the assigned number of streams if it is
57 * different from the original value. To prevent the endpoint
58 * from being returned by a later autoconfig call, claims it by
59 * assigning ep->claimed to true.
60 *
61 * On failure, this returns a null endpoint descriptor.
62 */
63struct usb_ep *usb_ep_autoconfig_ss(
64 struct usb_gadget *gadget,
65 struct usb_endpoint_descriptor *desc,
66 struct usb_ss_ep_comp_descriptor *ep_comp
67)
68{
69 struct usb_ep *ep;
70
71 if (gadget->ops->match_ep) {
72 ep = gadget->ops->match_ep(gadget, desc, ep_comp);
73 if (ep)
74 goto found_ep;
75 }
76
77 /* Second, look at endpoints until an unclaimed one looks usable */
78 list_for_each_entry (ep, &gadget->ep_list, ep_list) {
79 if (usb_gadget_ep_match_desc(gadget, ep, desc, ep_comp))
80 goto found_ep;
81 }
82
83 /* Fail */
84 return NULL;
85found_ep:
86
87 /*
88 * If the protocol driver hasn't yet decided on wMaxPacketSize
89 * and wants to know the maximum possible, provide the info.
90 */
91 if (desc->wMaxPacketSize == 0)
92 desc->wMaxPacketSize = cpu_to_le16(ep->maxpacket_limit);
93
94 /* report address */
95 desc->bEndpointAddress &= USB_DIR_IN;
96 if (isdigit(ep->name[2])) {
97 u8 num = simple_strtoul(&ep->name[2], NULL, 10);
98 desc->bEndpointAddress |= num;
99 } else if (desc->bEndpointAddress & USB_DIR_IN) {
100 if (++gadget->in_epnum > 15)
101 return NULL;
102 desc->bEndpointAddress = USB_DIR_IN | gadget->in_epnum;
103 } else {
104 if (++gadget->out_epnum > 15)
105 return NULL;
106 desc->bEndpointAddress |= gadget->out_epnum;
107 }
108
109 ep->address = desc->bEndpointAddress;
110 ep->desc = NULL;
111 ep->comp_desc = NULL;
112 ep->claimed = true;
113 return ep;
114}
115EXPORT_SYMBOL_GPL(usb_ep_autoconfig_ss);
116
117/**
118 * usb_ep_autoconfig() - choose an endpoint matching the
119 * descriptor
120 * @gadget: The device to which the endpoint must belong.
121 * @desc: Endpoint descriptor, with endpoint direction and transfer mode
122 * initialized. For periodic transfers, the maximum packet
123 * size must also be initialized. This is modified on success.
124 *
125 * By choosing an endpoint to use with the specified descriptor, this
126 * routine simplifies writing gadget drivers that work with multiple
127 * USB device controllers. The endpoint would be passed later to
128 * usb_ep_enable(), along with some descriptor.
129 *
130 * That second descriptor won't always be the same as the first one.
131 * For example, isochronous endpoints can be autoconfigured for high
132 * bandwidth, and then used in several lower bandwidth altsettings.
133 * Also, high and full speed descriptors will be different.
134 *
135 * Be sure to examine and test the results of autoconfiguration on your
136 * hardware. This code may not make the best choices about how to use the
137 * USB controller, and it can't know all the restrictions that may apply.
138 * Some combinations of driver and hardware won't be able to autoconfigure.
139 *
140 * On success, this returns an claimed usb_ep, and modifies the endpoint
141 * descriptor bEndpointAddress. For bulk endpoints, the wMaxPacket value
142 * is initialized as if the endpoint were used at full speed. Because of
143 * that the users must consider adjusting the autoconfigured descriptor.
144 * To prevent the endpoint from being returned by a later autoconfig call,
145 * claims it by assigning ep->claimed to true.
146 *
147 * On failure, this returns a null endpoint descriptor.
148 */
149struct usb_ep *usb_ep_autoconfig(
150 struct usb_gadget *gadget,
151 struct usb_endpoint_descriptor *desc
152)
153{
154 struct usb_ep *ep;
155 u8 type;
156
157 ep = usb_ep_autoconfig_ss(gadget, desc, NULL);
158 if (!ep)
159 return NULL;
160
161 type = desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK;
162
163 /* report (variable) full speed bulk maxpacket */
164 if (type == USB_ENDPOINT_XFER_BULK) {
165 int size = ep->maxpacket_limit;
166
167 /* min() doesn't work on bitfields with gcc-3.5 */
168 if (size > 64)
169 size = 64;
170 desc->wMaxPacketSize = cpu_to_le16(size);
171 }
172
173 return ep;
174}
175EXPORT_SYMBOL_GPL(usb_ep_autoconfig);
176
177/**
178 * usb_ep_autoconfig_release - releases endpoint and set it to initial state
179 * @ep: endpoint which should be released
180 *
181 * This function can be used during function bind for endpoints obtained
182 * from usb_ep_autoconfig(). It unclaims endpoint claimed by
183 * usb_ep_autoconfig() to make it available for other functions. Endpoint
184 * which was released is no longer valid and shouldn't be used in
185 * context of function which released it.
186 */
187void usb_ep_autoconfig_release(struct usb_ep *ep)
188{
189 ep->claimed = false;
190 ep->driver_data = NULL;
191}
192EXPORT_SYMBOL_GPL(usb_ep_autoconfig_release);
193
194/**
195 * usb_ep_autoconfig_reset - reset endpoint autoconfig state
196 * @gadget: device for which autoconfig state will be reset
197 *
198 * Use this for devices where one configuration may need to assign
199 * endpoint resources very differently from the next one. It clears
200 * state such as ep->claimed and the record of assigned endpoints
201 * used by usb_ep_autoconfig().
202 */
203void usb_ep_autoconfig_reset (struct usb_gadget *gadget)
204{
205 struct usb_ep *ep;
206
207 list_for_each_entry (ep, &gadget->ep_list, ep_list) {
208 ep->claimed = false;
209 ep->driver_data = NULL;
210 }
211 gadget->in_epnum = 0;
212 gadget->out_epnum = 0;
213}
214EXPORT_SYMBOL_GPL(usb_ep_autoconfig_reset);