2 * epautoconf.c -- endpoint autoconfiguration for usb gadget drivers
4 * Copyright (C) 2004 David Brownell
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.
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.
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
22 #include <linux/kernel.h>
23 #include <linux/init.h>
24 #include <linux/types.h>
25 #include <linux/device.h>
27 #include <linux/ctype.h>
28 #include <linux/string.h>
30 #include <linux/usb/ch9.h>
31 #include <linux/usb/gadget.h>
33 #include "gadget_chips.h"
36 /* we must assign addresses for configurable endpoints (like net2280) */
37 static unsigned epnum;
39 // #define MANY_ENDPOINTS
41 /* more than 15 configurable endpoints */
42 static unsigned in_epnum;
47 * This should work with endpoints from controller drivers sharing the
48 * same endpoint naming convention. By example:
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
56 * Type suffixes are "-bulk", "-iso", or "-int". Numbers are decimal.
57 * Less common restrictions are implied by gadget_is_*().
59 * NOTE: each endpoint is unidirectional, as specified by its USB
60 * descriptor; and isn't specific to a configuration or altsetting.
64 struct usb_gadget *gadget,
66 struct usb_endpoint_descriptor *desc
73 /* endpoint already claimed? */
74 if (NULL != ep->driver_data)
77 /* only support ep0 for portable CONTROL traffic */
78 type = desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK;
79 if (USB_ENDPOINT_XFER_CONTROL == type)
82 /* some other naming convention */
83 if ('e' != ep->name[0])
86 /* type-restriction: "-iso", "-bulk", or "-int".
87 * direction-restriction: "in", "out".
89 if ('-' != ep->name[2]) {
90 tmp = strrchr (ep->name, '-');
93 case USB_ENDPOINT_XFER_INT:
94 /* bulk endpoints handle interrupt transfers,
95 * except the toggle-quirky iso-synch kind
97 if ('s' == tmp[2]) // == "-iso"
99 /* for now, avoid PXA "interrupt-in";
100 * it's documented as never using DATA1.
102 if (gadget_is_pxa (gadget)
106 case USB_ENDPOINT_XFER_BULK:
107 if ('b' != tmp[1]) // != "-bulk"
110 case USB_ENDPOINT_XFER_ISOC:
111 if ('s' != tmp[2]) // != "-iso"
115 tmp = ep->name + strlen (ep->name);
118 /* direction-restriction: "..in-..", "out-.." */
120 if (!isdigit (*tmp)) {
121 if (desc->bEndpointAddress & USB_DIR_IN) {
132 * If the protocol driver hasn't yet decided on wMaxPacketSize
133 * and wants to know the maximum possible, provide the info.
135 if (desc->wMaxPacketSize == 0)
136 desc->wMaxPacketSize = cpu_to_le16(ep->maxpacket);
138 /* endpoint maxpacket size is an input parameter, except for bulk
139 * where it's an output parameter representing the full speed limit.
140 * the usb spec fixes high speed bulk maxpacket at 512 bytes.
142 max = 0x7ff & le16_to_cpu(desc->wMaxPacketSize);
144 case USB_ENDPOINT_XFER_INT:
145 /* INT: limit 64 bytes full speed, 1024 high speed */
146 if (!gadget->is_dualspeed && max > 64)
150 case USB_ENDPOINT_XFER_ISOC:
151 /* ISO: limit 1023 bytes full speed, 1024 high speed */
152 if (ep->maxpacket < max)
154 if (!gadget->is_dualspeed && max > 1023)
157 /* BOTH: "high bandwidth" works only at high speed */
158 if ((desc->wMaxPacketSize & cpu_to_le16(3<<11))) {
159 if (!gadget->is_dualspeed)
161 /* configure your hardware with enough buffering!! */
169 desc->bEndpointAddress &= USB_DIR_IN;
170 if (isdigit (ep->name [2])) {
171 u8 num = simple_strtoul (&ep->name [2], NULL, 10);
172 desc->bEndpointAddress |= num;
173 #ifdef MANY_ENDPOINTS
174 } else if (desc->bEndpointAddress & USB_DIR_IN) {
177 desc->bEndpointAddress = USB_DIR_IN | in_epnum;
182 desc->bEndpointAddress |= epnum;
185 /* report (variable) full speed bulk maxpacket */
186 if (USB_ENDPOINT_XFER_BULK == type) {
187 int size = ep->maxpacket;
189 /* min() doesn't work on bitfields with gcc-3.5 */
192 desc->wMaxPacketSize = cpu_to_le16(size);
197 static struct usb_ep *
198 find_ep (struct usb_gadget *gadget, const char *name)
202 list_for_each_entry (ep, &gadget->ep_list, ep_list) {
203 if (0 == strcmp (ep->name, name))
210 * usb_ep_autoconfig - choose an endpoint matching the descriptor
211 * @gadget: The device to which the endpoint must belong.
212 * @desc: Endpoint descriptor, with endpoint direction and transfer mode
213 * initialized. For periodic transfers, the maximum packet
214 * size must also be initialized. This is modified on success.
216 * By choosing an endpoint to use with the specified descriptor, this
217 * routine simplifies writing gadget drivers that work with multiple
218 * USB device controllers. The endpoint would be passed later to
219 * usb_ep_enable(), along with some descriptor.
221 * That second descriptor won't always be the same as the first one.
222 * For example, isochronous endpoints can be autoconfigured for high
223 * bandwidth, and then used in several lower bandwidth altsettings.
224 * Also, high and full speed descriptors will be different.
226 * Be sure to examine and test the results of autoconfiguration on your
227 * hardware. This code may not make the best choices about how to use the
228 * USB controller, and it can't know all the restrictions that may apply.
229 * Some combinations of driver and hardware won't be able to autoconfigure.
231 * On success, this returns an un-claimed usb_ep, and modifies the endpoint
232 * descriptor bEndpointAddress. For bulk endpoints, the wMaxPacket value
233 * is initialized as if the endpoint were used at full speed. To prevent
234 * the endpoint from being returned by a later autoconfig call, claim it
235 * by assigning ep->driver_data to some non-null value.
237 * On failure, this returns a null endpoint descriptor.
239 struct usb_ep *usb_ep_autoconfig (
240 struct usb_gadget *gadget,
241 struct usb_endpoint_descriptor *desc
247 type = desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK;
249 /* First, apply chip-specific "best usage" knowledge.
250 * This might make a good usb_gadget_ops hook ...
252 if (gadget_is_net2280 (gadget) && type == USB_ENDPOINT_XFER_INT) {
253 /* ep-e, ep-f are PIO with only 64 byte fifos */
254 ep = find_ep (gadget, "ep-e");
255 if (ep && ep_matches (gadget, ep, desc))
257 ep = find_ep (gadget, "ep-f");
258 if (ep && ep_matches (gadget, ep, desc))
261 } else if (gadget_is_goku (gadget)) {
262 if (USB_ENDPOINT_XFER_INT == type) {
263 /* single buffering is enough */
264 ep = find_ep (gadget, "ep3-bulk");
265 if (ep && ep_matches (gadget, ep, desc))
267 } else if (USB_ENDPOINT_XFER_BULK == type
268 && (USB_DIR_IN & desc->bEndpointAddress)) {
269 /* DMA may be available */
270 ep = find_ep (gadget, "ep2-bulk");
271 if (ep && ep_matches (gadget, ep, desc))
275 #ifdef CONFIG_BLACKFIN
276 } else if (gadget_is_musbhdrc(gadget)) {
277 if ((USB_ENDPOINT_XFER_BULK == type) ||
278 (USB_ENDPOINT_XFER_ISOC == type)) {
279 if (USB_DIR_IN & desc->bEndpointAddress)
280 ep = find_ep (gadget, "ep5in");
282 ep = find_ep (gadget, "ep6out");
283 } else if (USB_ENDPOINT_XFER_INT == type) {
284 if (USB_DIR_IN & desc->bEndpointAddress)
285 ep = find_ep(gadget, "ep1in");
287 ep = find_ep(gadget, "ep2out");
290 if (ep && ep_matches (gadget, ep, desc))
295 /* Second, look at endpoints until an unclaimed one looks usable */
296 list_for_each_entry (ep, &gadget->ep_list, ep_list) {
297 if (ep_matches (gadget, ep, desc))
306 * usb_ep_autoconfig_reset - reset endpoint autoconfig state
307 * @gadget: device for which autoconfig state will be reset
309 * Use this for devices where one configuration may need to assign
310 * endpoint resources very differently from the next one. It clears
311 * state such as ep->driver_data and the record of assigned endpoints
312 * used by usb_ep_autoconfig().
314 void usb_ep_autoconfig_reset (struct usb_gadget *gadget)
318 list_for_each_entry (ep, &gadget->ep_list, ep_list) {
319 ep->driver_data = NULL;
321 #ifdef MANY_ENDPOINTS