xref: /linux/drivers/usb/gadget/legacy/zero.c (revision 93df8a1ed6231727c5db94a80b1a6bd5ee67cec3)
1 /*
2  * zero.c -- Gadget Zero, for USB development
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 
13 /*
14  * Gadget Zero only needs two bulk endpoints, and is an example of how you
15  * can write a hardware-agnostic gadget driver running inside a USB device.
16  * Some hardware details are visible, but don't affect most of the driver.
17  *
18  * Use it with the Linux host/master side "usbtest" driver to get a basic
19  * functional test of your device-side usb stack, or with "usb-skeleton".
20  *
21  * It supports two similar configurations.  One sinks whatever the usb host
22  * writes, and in return sources zeroes.  The other loops whatever the host
23  * writes back, so the host can read it.
24  *
25  * Many drivers will only have one configuration, letting them be much
26  * simpler if they also don't support high speed operation (like this
27  * driver does).
28  *
29  * Why is *this* driver using two configurations, rather than setting up
30  * two interfaces with different functions?  To help verify that multiple
31  * configuration infrastructure is working correctly; also, so that it can
32  * work with low capability USB controllers without four bulk endpoints.
33  */
34 
35 /*
36  * driver assumes self-powered hardware, and
37  * has no way for users to trigger remote wakeup.
38  */
39 
40 /* #define VERBOSE_DEBUG */
41 
42 #include <linux/kernel.h>
43 #include <linux/slab.h>
44 #include <linux/device.h>
45 #include <linux/module.h>
46 #include <linux/err.h>
47 #include <linux/usb/composite.h>
48 
49 #include "g_zero.h"
50 /*-------------------------------------------------------------------------*/
51 USB_GADGET_COMPOSITE_OPTIONS();
52 
53 #define DRIVER_VERSION		"Cinco de Mayo 2008"
54 
55 static const char longname[] = "Gadget Zero";
56 
57 /*
58  * Normally the "loopback" configuration is second (index 1) so
59  * it's not the default.  Here's where to change that order, to
60  * work better with hosts where config changes are problematic or
61  * controllers (like original superh) that only support one config.
62  */
63 static bool loopdefault = 0;
64 module_param(loopdefault, bool, S_IRUGO|S_IWUSR);
65 
66 static struct usb_zero_options gzero_options = {
67 	.isoc_interval = GZERO_ISOC_INTERVAL,
68 	.isoc_maxpacket = GZERO_ISOC_MAXPACKET,
69 	.bulk_buflen = GZERO_BULK_BUFLEN,
70 	.qlen = GZERO_QLEN,
71 };
72 
73 /*-------------------------------------------------------------------------*/
74 
75 /* Thanks to NetChip Technologies for donating this product ID.
76  *
77  * DO NOT REUSE THESE IDs with a protocol-incompatible driver!!  Ever!!
78  * Instead:  allocate your own, using normal USB-IF procedures.
79  */
80 #ifndef	CONFIG_USB_ZERO_HNPTEST
81 #define DRIVER_VENDOR_NUM	0x0525		/* NetChip */
82 #define DRIVER_PRODUCT_NUM	0xa4a0		/* Linux-USB "Gadget Zero" */
83 #define DEFAULT_AUTORESUME	0
84 #else
85 #define DRIVER_VENDOR_NUM	0x1a0a		/* OTG test device IDs */
86 #define DRIVER_PRODUCT_NUM	0xbadd
87 #define DEFAULT_AUTORESUME	5
88 #endif
89 
90 /* If the optional "autoresume" mode is enabled, it provides good
91  * functional coverage for the "USBCV" test harness from USB-IF.
92  * It's always set if OTG mode is enabled.
93  */
94 static unsigned autoresume = DEFAULT_AUTORESUME;
95 module_param(autoresume, uint, S_IRUGO);
96 MODULE_PARM_DESC(autoresume, "zero, or seconds before remote wakeup");
97 
98 /* Maximum Autoresume time */
99 static unsigned max_autoresume;
100 module_param(max_autoresume, uint, S_IRUGO);
101 MODULE_PARM_DESC(max_autoresume, "maximum seconds before remote wakeup");
102 
103 /* Interval between two remote wakeups */
104 static unsigned autoresume_interval_ms;
105 module_param(autoresume_interval_ms, uint, S_IRUGO);
106 MODULE_PARM_DESC(autoresume_interval_ms,
107 		"milliseconds to increase successive wakeup delays");
108 
109 static unsigned autoresume_step_ms;
110 /*-------------------------------------------------------------------------*/
111 
112 static struct usb_device_descriptor device_desc = {
113 	.bLength =		sizeof device_desc,
114 	.bDescriptorType =	USB_DT_DEVICE,
115 
116 	.bcdUSB =		cpu_to_le16(0x0200),
117 	.bDeviceClass =		USB_CLASS_VENDOR_SPEC,
118 
119 	.idVendor =		cpu_to_le16(DRIVER_VENDOR_NUM),
120 	.idProduct =		cpu_to_le16(DRIVER_PRODUCT_NUM),
121 	.bNumConfigurations =	2,
122 };
123 
124 #ifdef CONFIG_USB_OTG
125 static struct usb_otg_descriptor otg_descriptor = {
126 	.bLength =		sizeof otg_descriptor,
127 	.bDescriptorType =	USB_DT_OTG,
128 
129 	/* REVISIT SRP-only hardware is possible, although
130 	 * it would not be called "OTG" ...
131 	 */
132 	.bmAttributes =		USB_OTG_SRP | USB_OTG_HNP,
133 };
134 
135 static const struct usb_descriptor_header *otg_desc[] = {
136 	(struct usb_descriptor_header *) &otg_descriptor,
137 	NULL,
138 };
139 #else
140 #define otg_desc	NULL
141 #endif
142 
143 /* string IDs are assigned dynamically */
144 /* default serial number takes at least two packets */
145 static char serial[] = "0123456789.0123456789.0123456789";
146 
147 #define USB_GZERO_SS_DESC	(USB_GADGET_FIRST_AVAIL_IDX + 0)
148 #define USB_GZERO_LB_DESC	(USB_GADGET_FIRST_AVAIL_IDX + 1)
149 
150 static struct usb_string strings_dev[] = {
151 	[USB_GADGET_MANUFACTURER_IDX].s = "",
152 	[USB_GADGET_PRODUCT_IDX].s = longname,
153 	[USB_GADGET_SERIAL_IDX].s = serial,
154 	[USB_GZERO_SS_DESC].s	= "source and sink data",
155 	[USB_GZERO_LB_DESC].s	= "loop input to output",
156 	{  }			/* end of list */
157 };
158 
159 static struct usb_gadget_strings stringtab_dev = {
160 	.language	= 0x0409,	/* en-us */
161 	.strings	= strings_dev,
162 };
163 
164 static struct usb_gadget_strings *dev_strings[] = {
165 	&stringtab_dev,
166 	NULL,
167 };
168 
169 /*-------------------------------------------------------------------------*/
170 
171 static struct timer_list	autoresume_timer;
172 
173 static void zero_autoresume(unsigned long _c)
174 {
175 	struct usb_composite_dev	*cdev = (void *)_c;
176 	struct usb_gadget		*g = cdev->gadget;
177 
178 	/* unconfigured devices can't issue wakeups */
179 	if (!cdev->config)
180 		return;
181 
182 	/* Normally the host would be woken up for something
183 	 * more significant than just a timer firing; likely
184 	 * because of some direct user request.
185 	 */
186 	if (g->speed != USB_SPEED_UNKNOWN) {
187 		int status = usb_gadget_wakeup(g);
188 		INFO(cdev, "%s --> %d\n", __func__, status);
189 	}
190 }
191 
192 static void zero_suspend(struct usb_composite_dev *cdev)
193 {
194 	if (cdev->gadget->speed == USB_SPEED_UNKNOWN)
195 		return;
196 
197 	if (autoresume) {
198 		if (max_autoresume &&
199 			(autoresume_step_ms > max_autoresume * 1000))
200 				autoresume_step_ms = autoresume * 1000;
201 
202 		mod_timer(&autoresume_timer, jiffies +
203 			msecs_to_jiffies(autoresume_step_ms));
204 		DBG(cdev, "suspend, wakeup in %d milliseconds\n",
205 			autoresume_step_ms);
206 
207 		autoresume_step_ms += autoresume_interval_ms;
208 	} else
209 		DBG(cdev, "%s\n", __func__);
210 }
211 
212 static void zero_resume(struct usb_composite_dev *cdev)
213 {
214 	DBG(cdev, "%s\n", __func__);
215 	del_timer(&autoresume_timer);
216 }
217 
218 /*-------------------------------------------------------------------------*/
219 
220 static struct usb_configuration loopback_driver = {
221 	.label          = "loopback",
222 	.bConfigurationValue = 2,
223 	.bmAttributes   = USB_CONFIG_ATT_SELFPOWER,
224 	/* .iConfiguration = DYNAMIC */
225 };
226 
227 static struct usb_function *func_ss;
228 static struct usb_function_instance *func_inst_ss;
229 
230 static int ss_config_setup(struct usb_configuration *c,
231 		const struct usb_ctrlrequest *ctrl)
232 {
233 	switch (ctrl->bRequest) {
234 	case 0x5b:
235 	case 0x5c:
236 		return func_ss->setup(func_ss, ctrl);
237 	default:
238 		return -EOPNOTSUPP;
239 	}
240 }
241 
242 static struct usb_configuration sourcesink_driver = {
243 	.label                  = "source/sink",
244 	.setup                  = ss_config_setup,
245 	.bConfigurationValue    = 3,
246 	.bmAttributes           = USB_CONFIG_ATT_SELFPOWER,
247 	/* .iConfiguration      = DYNAMIC */
248 };
249 
250 module_param_named(buflen, gzero_options.bulk_buflen, uint, 0);
251 module_param_named(pattern, gzero_options.pattern, uint, S_IRUGO|S_IWUSR);
252 MODULE_PARM_DESC(pattern, "0 = all zeroes, 1 = mod63, 2 = none");
253 
254 module_param_named(isoc_interval, gzero_options.isoc_interval, uint,
255 		S_IRUGO|S_IWUSR);
256 MODULE_PARM_DESC(isoc_interval, "1 - 16");
257 
258 module_param_named(isoc_maxpacket, gzero_options.isoc_maxpacket, uint,
259 		S_IRUGO|S_IWUSR);
260 MODULE_PARM_DESC(isoc_maxpacket, "0 - 1023 (fs), 0 - 1024 (hs/ss)");
261 
262 module_param_named(isoc_mult, gzero_options.isoc_mult, uint, S_IRUGO|S_IWUSR);
263 MODULE_PARM_DESC(isoc_mult, "0 - 2 (hs/ss only)");
264 
265 module_param_named(isoc_maxburst, gzero_options.isoc_maxburst, uint,
266 		S_IRUGO|S_IWUSR);
267 MODULE_PARM_DESC(isoc_maxburst, "0 - 15 (ss only)");
268 
269 static struct usb_function *func_lb;
270 static struct usb_function_instance *func_inst_lb;
271 
272 module_param_named(qlen, gzero_options.qlen, uint, S_IRUGO|S_IWUSR);
273 MODULE_PARM_DESC(qlen, "depth of loopback queue");
274 
275 static int zero_bind(struct usb_composite_dev *cdev)
276 {
277 	struct f_ss_opts	*ss_opts;
278 	struct f_lb_opts	*lb_opts;
279 	int			status;
280 
281 	/* Allocate string descriptor numbers ... note that string
282 	 * contents can be overridden by the composite_dev glue.
283 	 */
284 	status = usb_string_ids_tab(cdev, strings_dev);
285 	if (status < 0)
286 		return status;
287 
288 	device_desc.iManufacturer = strings_dev[USB_GADGET_MANUFACTURER_IDX].id;
289 	device_desc.iProduct = strings_dev[USB_GADGET_PRODUCT_IDX].id;
290 	device_desc.iSerialNumber = strings_dev[USB_GADGET_SERIAL_IDX].id;
291 
292 	setup_timer(&autoresume_timer, zero_autoresume, (unsigned long) cdev);
293 
294 	func_inst_ss = usb_get_function_instance("SourceSink");
295 	if (IS_ERR(func_inst_ss))
296 		return PTR_ERR(func_inst_ss);
297 
298 	ss_opts =  container_of(func_inst_ss, struct f_ss_opts, func_inst);
299 	ss_opts->pattern = gzero_options.pattern;
300 	ss_opts->isoc_interval = gzero_options.isoc_interval;
301 	ss_opts->isoc_maxpacket = gzero_options.isoc_maxpacket;
302 	ss_opts->isoc_mult = gzero_options.isoc_mult;
303 	ss_opts->isoc_maxburst = gzero_options.isoc_maxburst;
304 	ss_opts->bulk_buflen = gzero_options.bulk_buflen;
305 
306 	func_ss = usb_get_function(func_inst_ss);
307 	if (IS_ERR(func_ss)) {
308 		status = PTR_ERR(func_ss);
309 		goto err_put_func_inst_ss;
310 	}
311 
312 	func_inst_lb = usb_get_function_instance("Loopback");
313 	if (IS_ERR(func_inst_lb)) {
314 		status = PTR_ERR(func_inst_lb);
315 		goto err_put_func_ss;
316 	}
317 
318 	lb_opts = container_of(func_inst_lb, struct f_lb_opts, func_inst);
319 	lb_opts->bulk_buflen = gzero_options.bulk_buflen;
320 	lb_opts->qlen = gzero_options.qlen;
321 
322 	func_lb = usb_get_function(func_inst_lb);
323 	if (IS_ERR(func_lb)) {
324 		status = PTR_ERR(func_lb);
325 		goto err_put_func_inst_lb;
326 	}
327 
328 	sourcesink_driver.iConfiguration = strings_dev[USB_GZERO_SS_DESC].id;
329 	loopback_driver.iConfiguration = strings_dev[USB_GZERO_LB_DESC].id;
330 
331 	/* support autoresume for remote wakeup testing */
332 	sourcesink_driver.bmAttributes &= ~USB_CONFIG_ATT_WAKEUP;
333 	loopback_driver.bmAttributes &= ~USB_CONFIG_ATT_WAKEUP;
334 	sourcesink_driver.descriptors = NULL;
335 	loopback_driver.descriptors = NULL;
336 	if (autoresume) {
337 		sourcesink_driver.bmAttributes |= USB_CONFIG_ATT_WAKEUP;
338 		loopback_driver.bmAttributes |= USB_CONFIG_ATT_WAKEUP;
339 		autoresume_step_ms = autoresume * 1000;
340 	}
341 
342 	/* support OTG systems */
343 	if (gadget_is_otg(cdev->gadget)) {
344 		sourcesink_driver.descriptors = otg_desc;
345 		sourcesink_driver.bmAttributes |= USB_CONFIG_ATT_WAKEUP;
346 		loopback_driver.descriptors = otg_desc;
347 		loopback_driver.bmAttributes |= USB_CONFIG_ATT_WAKEUP;
348 	}
349 
350 	/* Register primary, then secondary configuration.  Note that
351 	 * SH3 only allows one config...
352 	 */
353 	if (loopdefault) {
354 		usb_add_config_only(cdev, &loopback_driver);
355 		usb_add_config_only(cdev, &sourcesink_driver);
356 	} else {
357 		usb_add_config_only(cdev, &sourcesink_driver);
358 		usb_add_config_only(cdev, &loopback_driver);
359 	}
360 	status = usb_add_function(&sourcesink_driver, func_ss);
361 	if (status)
362 		goto err_conf_flb;
363 
364 	usb_ep_autoconfig_reset(cdev->gadget);
365 	status = usb_add_function(&loopback_driver, func_lb);
366 	if (status)
367 		goto err_conf_flb;
368 
369 	usb_ep_autoconfig_reset(cdev->gadget);
370 	usb_composite_overwrite_options(cdev, &coverwrite);
371 
372 	INFO(cdev, "%s, version: " DRIVER_VERSION "\n", longname);
373 
374 	return 0;
375 
376 err_conf_flb:
377 	usb_put_function(func_lb);
378 	func_lb = NULL;
379 err_put_func_inst_lb:
380 	usb_put_function_instance(func_inst_lb);
381 	func_inst_lb = NULL;
382 err_put_func_ss:
383 	usb_put_function(func_ss);
384 	func_ss = NULL;
385 err_put_func_inst_ss:
386 	usb_put_function_instance(func_inst_ss);
387 	func_inst_ss = NULL;
388 	return status;
389 }
390 
391 static int zero_unbind(struct usb_composite_dev *cdev)
392 {
393 	del_timer_sync(&autoresume_timer);
394 	if (!IS_ERR_OR_NULL(func_ss))
395 		usb_put_function(func_ss);
396 	usb_put_function_instance(func_inst_ss);
397 	if (!IS_ERR_OR_NULL(func_lb))
398 		usb_put_function(func_lb);
399 	usb_put_function_instance(func_inst_lb);
400 	return 0;
401 }
402 
403 static struct usb_composite_driver zero_driver = {
404 	.name		= "zero",
405 	.dev		= &device_desc,
406 	.strings	= dev_strings,
407 	.max_speed	= USB_SPEED_SUPER,
408 	.bind		= zero_bind,
409 	.unbind		= zero_unbind,
410 	.suspend	= zero_suspend,
411 	.resume		= zero_resume,
412 };
413 
414 module_usb_composite_driver(zero_driver);
415 
416 MODULE_AUTHOR("David Brownell");
417 MODULE_LICENSE("GPL");
418