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authorDavid Brownell <dbrownell@users.sourceforge.net>2008-06-19 20:55:35 -0400
committerGreg Kroah-Hartman <gregkh@suse.de>2008-07-21 18:16:03 -0400
commite5760fdac8c8aeca060d1afc8a233ea3d7a46720 (patch)
tree2845c06bf7415f12cc52aff3ffe41dd28b22a7ec /drivers/usb/gadget/f_loopback.c
parenta400cadc0774c31f67c419a835d80ba611128c2a (diff)
usb gadget zero: split out loopback config
This splits the gadget zero "loopback" configuration into a standalone "configuration driver", building on the composite gadget framework code. It doesn't yet pull the original code out of gadget zero or update how that driver is built. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/usb/gadget/f_loopback.c')
-rw-r--r--drivers/usb/gadget/f_loopback.c381
1 files changed, 381 insertions, 0 deletions
diff --git a/drivers/usb/gadget/f_loopback.c b/drivers/usb/gadget/f_loopback.c
new file mode 100644
index 000000000000..eda4cde72c82
--- /dev/null
+++ b/drivers/usb/gadget/f_loopback.c
@@ -0,0 +1,381 @@
1/*
2 * f_loopback.c - USB peripheral loopback configuration driver
3 *
4 * Copyright (C) 2003-2008 David Brownell
5 * Copyright (C) 2008 by Nokia Corporation
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 */
21
22/* #define VERBOSE_DEBUG */
23
24#include <linux/kernel.h>
25#include <linux/utsname.h>
26#include <linux/device.h>
27
28#include "g_zero.h"
29#include "gadget_chips.h"
30
31
32/*
33 * LOOPBACK FUNCTION ... a testing vehicle for USB peripherals,
34 *
35 * This takes messages of various sizes written OUT to a device, and loops
36 * them back so they can be read IN from it. It has been used by certain
37 * test applications. It supports limited testing of data queueing logic.
38 *
39 *
40 * This is currently packaged as a configuration driver, which can't be
41 * combined with other functions to make composite devices. However, it
42 * can be combined with other independent configurations.
43 */
44struct f_loopback {
45 struct usb_function function;
46
47 struct usb_ep *in_ep;
48 struct usb_ep *out_ep;
49};
50
51static inline struct f_loopback *func_to_loop(struct usb_function *f)
52{
53 return container_of(f, struct f_loopback, function);
54}
55
56static unsigned qlen = 32;
57module_param(qlen, uint, 0);
58MODULE_PARM_DESC(qlenn, "depth of loopback queue");
59
60/*-------------------------------------------------------------------------*/
61
62static struct usb_interface_descriptor loopback_intf = {
63 .bLength = sizeof loopback_intf,
64 .bDescriptorType = USB_DT_INTERFACE,
65
66 .bNumEndpoints = 2,
67 .bInterfaceClass = USB_CLASS_VENDOR_SPEC,
68 /* .iInterface = DYNAMIC */
69};
70
71/* full speed support: */
72
73static struct usb_endpoint_descriptor fs_source_desc = {
74 .bLength = USB_DT_ENDPOINT_SIZE,
75 .bDescriptorType = USB_DT_ENDPOINT,
76
77 .bEndpointAddress = USB_DIR_IN,
78 .bmAttributes = USB_ENDPOINT_XFER_BULK,
79};
80
81static struct usb_endpoint_descriptor fs_sink_desc = {
82 .bLength = USB_DT_ENDPOINT_SIZE,
83 .bDescriptorType = USB_DT_ENDPOINT,
84
85 .bEndpointAddress = USB_DIR_OUT,
86 .bmAttributes = USB_ENDPOINT_XFER_BULK,
87};
88
89static struct usb_descriptor_header *fs_loopback_descs[] = {
90 (struct usb_descriptor_header *) &loopback_intf,
91 (struct usb_descriptor_header *) &fs_sink_desc,
92 (struct usb_descriptor_header *) &fs_source_desc,
93 NULL,
94};
95
96/* high speed support: */
97
98static struct usb_endpoint_descriptor hs_source_desc = {
99 .bLength = USB_DT_ENDPOINT_SIZE,
100 .bDescriptorType = USB_DT_ENDPOINT,
101
102 .bmAttributes = USB_ENDPOINT_XFER_BULK,
103 .wMaxPacketSize = __constant_cpu_to_le16(512),
104};
105
106static struct usb_endpoint_descriptor hs_sink_desc = {
107 .bLength = USB_DT_ENDPOINT_SIZE,
108 .bDescriptorType = USB_DT_ENDPOINT,
109
110 .bmAttributes = USB_ENDPOINT_XFER_BULK,
111 .wMaxPacketSize = __constant_cpu_to_le16(512),
112};
113
114static struct usb_descriptor_header *hs_loopback_descs[] = {
115 (struct usb_descriptor_header *) &loopback_intf,
116 (struct usb_descriptor_header *) &hs_source_desc,
117 (struct usb_descriptor_header *) &hs_sink_desc,
118 NULL,
119};
120
121/* function-specific strings: */
122
123static struct usb_string strings_loopback[] = {
124 [0].s = "loop input to output",
125 { } /* end of list */
126};
127
128static struct usb_gadget_strings stringtab_loop = {
129 .language = 0x0409, /* en-us */
130 .strings = strings_loopback,
131};
132
133static struct usb_gadget_strings *loopback_strings[] = {
134 &stringtab_loop,
135 NULL,
136};
137
138/*-------------------------------------------------------------------------*/
139
140static int __init
141loopback_bind(struct usb_configuration *c, struct usb_function *f)
142{
143 struct usb_composite_dev *cdev = c->cdev;
144 struct f_loopback *loop = func_to_loop(f);
145 int id;
146
147 /* allocate interface ID(s) */
148 id = usb_interface_id(c, f);
149 if (id < 0)
150 return id;
151 loopback_intf.bInterfaceNumber = id;
152
153 /* allocate endpoints */
154
155 loop->in_ep = usb_ep_autoconfig(cdev->gadget, &fs_source_desc);
156 if (!loop->in_ep) {
157autoconf_fail:
158 ERROR(cdev, "%s: can't autoconfigure on %s\n",
159 f->name, cdev->gadget->name);
160 return -ENODEV;
161 }
162 loop->in_ep->driver_data = cdev; /* claim */
163
164 loop->out_ep = usb_ep_autoconfig(cdev->gadget, &fs_sink_desc);
165 if (!loop->out_ep)
166 goto autoconf_fail;
167 loop->out_ep->driver_data = cdev; /* claim */
168
169 /* support high speed hardware */
170 if (gadget_is_dualspeed(c->cdev->gadget)) {
171 hs_source_desc.bEndpointAddress =
172 fs_source_desc.bEndpointAddress;
173 hs_sink_desc.bEndpointAddress =
174 fs_sink_desc.bEndpointAddress;
175 f->hs_descriptors = hs_loopback_descs;
176 }
177
178 DBG(cdev, "%s speed %s: IN/%s, OUT/%s\n",
179 gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full",
180 f->name, loop->in_ep->name, loop->out_ep->name);
181 return 0;
182}
183
184static void
185loopback_unbind(struct usb_configuration *c, struct usb_function *f)
186{
187 kfree(func_to_loop(f));
188}
189
190static void loopback_complete(struct usb_ep *ep, struct usb_request *req)
191{
192 struct f_loopback *loop = ep->driver_data;
193 struct usb_composite_dev *cdev = loop->function.config->cdev;
194 int status = req->status;
195
196 switch (status) {
197
198 case 0: /* normal completion? */
199 if (ep == loop->out_ep) {
200 /* loop this OUT packet back IN to the host */
201 req->zero = (req->actual < req->length);
202 req->length = req->actual;
203 status = usb_ep_queue(loop->in_ep, req, GFP_ATOMIC);
204 if (status == 0)
205 return;
206
207 /* "should never get here" */
208 ERROR(cdev, "can't loop %s to %s: %d\n",
209 ep->name, loop->in_ep->name,
210 status);
211 }
212
213 /* queue the buffer for some later OUT packet */
214 req->length = buflen;
215 status = usb_ep_queue(loop->out_ep, req, GFP_ATOMIC);
216 if (status == 0)
217 return;
218
219 /* "should never get here" */
220 /* FALLTHROUGH */
221
222 default:
223 ERROR(cdev, "%s loop complete --> %d, %d/%d\n", ep->name,
224 status, req->actual, req->length);
225 /* FALLTHROUGH */
226
227 /* NOTE: since this driver doesn't maintain an explicit record
228 * of requests it submitted (just maintains qlen count), we
229 * rely on the hardware driver to clean up on disconnect or
230 * endpoint disable.
231 */
232 case -ECONNABORTED: /* hardware forced ep reset */
233 case -ECONNRESET: /* request dequeued */
234 case -ESHUTDOWN: /* disconnect from host */
235 free_ep_req(ep, req);
236 return;
237 }
238}
239
240static void disable_loopback(struct f_loopback *loop)
241{
242 struct usb_composite_dev *cdev;
243
244 cdev = loop->function.config->cdev;
245 disable_endpoints(cdev, loop->in_ep, loop->out_ep);
246 VDBG(cdev, "%s disabled\n", loop->function.name);
247}
248
249static int
250enable_loopback(struct usb_composite_dev *cdev, struct f_loopback *loop)
251{
252 int result = 0;
253 const struct usb_endpoint_descriptor *src, *sink;
254 struct usb_ep *ep;
255 struct usb_request *req;
256 unsigned i;
257
258 src = ep_choose(cdev->gadget, &hs_source_desc, &fs_source_desc);
259 sink = ep_choose(cdev->gadget, &hs_sink_desc, &fs_sink_desc);
260
261 /* one endpoint writes data back IN to the host */
262 ep = loop->in_ep;
263 result = usb_ep_enable(ep, src);
264 if (result < 0)
265 return result;
266 ep->driver_data = loop;
267
268 /* one endpoint just reads OUT packets */
269 ep = loop->out_ep;
270 result = usb_ep_enable(ep, sink);
271 if (result < 0) {
272fail0:
273 ep = loop->in_ep;
274 usb_ep_disable(ep);
275 ep->driver_data = NULL;
276 return result;
277 }
278 ep->driver_data = loop;
279
280 /* allocate a bunch of read buffers and queue them all at once.
281 * we buffer at most 'qlen' transfers; fewer if any need more
282 * than 'buflen' bytes each.
283 */
284 for (i = 0; i < qlen && result == 0; i++) {
285 req = alloc_ep_req(ep);
286 if (req) {
287 req->complete = loopback_complete;
288 result = usb_ep_queue(ep, req, GFP_ATOMIC);
289 if (result)
290 ERROR(cdev, "%s queue req --> %d\n",
291 ep->name, result);
292 } else {
293 usb_ep_disable(ep);
294 ep->driver_data = NULL;
295 result = -ENOMEM;
296 goto fail0;
297 }
298 }
299
300 DBG(cdev, "%s enabled\n", loop->function.name);
301 return result;
302}
303
304static int loopback_set_alt(struct usb_function *f,
305 unsigned intf, unsigned alt)
306{
307 struct f_loopback *loop = func_to_loop(f);
308 struct usb_composite_dev *cdev = f->config->cdev;
309
310 /* we know alt is zero */
311 if (loop->in_ep->driver_data)
312 disable_loopback(loop);
313 return enable_loopback(cdev, loop);
314}
315
316static void loopback_disable(struct usb_function *f)
317{
318 struct f_loopback *loop = func_to_loop(f);
319
320 disable_loopback(loop);
321}
322
323/*-------------------------------------------------------------------------*/
324
325static int __init loopback_bind_config(struct usb_configuration *c)
326{
327 struct f_loopback *loop;
328 int status;
329
330 loop = kzalloc(sizeof *loop, GFP_KERNEL);
331 if (!loop)
332 return -ENOMEM;
333
334 loop->function.name = "loopback";
335 loop->function.descriptors = fs_loopback_descs;
336 loop->function.bind = loopback_bind;
337 loop->function.unbind = loopback_unbind;
338 loop->function.set_alt = loopback_set_alt;
339 loop->function.disable = loopback_disable;
340
341 status = usb_add_function(c, &loop->function);
342 if (status)
343 kfree(loop);
344 return status;
345}
346
347static struct usb_configuration loopback_driver = {
348 .label = "loopback",
349 .strings = loopback_strings,
350 .bind = loopback_bind_config,
351 .bConfigurationValue = 2,
352 .bmAttributes = USB_CONFIG_ATT_SELFPOWER,
353 .bMaxPower = 1, /* 2 mA, minimal */
354 /* .iConfiguration = DYNAMIC */
355};
356
357/**
358 * loopback_add - add a loopback testing configuration to a device
359 * @cdev: the device to support the loopback configuration
360 */
361int __init loopback_add(struct usb_composite_dev *cdev)
362{
363 int id;
364
365 /* allocate string ID(s) */
366 id = usb_string_id(cdev);
367 if (id < 0)
368 return id;
369 strings_loopback[0].id = id;
370
371 loopback_intf.iInterface = id;
372 loopback_driver.iConfiguration = id;
373
374 /* support OTG systems */
375 if (gadget_is_otg(cdev->gadget)) {
376 loopback_driver.descriptors = otg_desc;
377 loopback_driver.bmAttributes |= USB_CONFIG_ATT_WAKEUP;
378 }
379
380 return usb_add_config(cdev, &loopback_driver);
381}