xref: /openbmc/linux/drivers/usb/gadget/legacy/zero.c (revision ca55b2fe)
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 static const struct usb_descriptor_header *otg_desc[2];
125 
126 /* string IDs are assigned dynamically */
127 /* default serial number takes at least two packets */
128 static char serial[] = "0123456789.0123456789.0123456789";
129 
130 #define USB_GZERO_SS_DESC	(USB_GADGET_FIRST_AVAIL_IDX + 0)
131 #define USB_GZERO_LB_DESC	(USB_GADGET_FIRST_AVAIL_IDX + 1)
132 
133 static struct usb_string strings_dev[] = {
134 	[USB_GADGET_MANUFACTURER_IDX].s = "",
135 	[USB_GADGET_PRODUCT_IDX].s = longname,
136 	[USB_GADGET_SERIAL_IDX].s = serial,
137 	[USB_GZERO_SS_DESC].s	= "source and sink data",
138 	[USB_GZERO_LB_DESC].s	= "loop input to output",
139 	{  }			/* end of list */
140 };
141 
142 static struct usb_gadget_strings stringtab_dev = {
143 	.language	= 0x0409,	/* en-us */
144 	.strings	= strings_dev,
145 };
146 
147 static struct usb_gadget_strings *dev_strings[] = {
148 	&stringtab_dev,
149 	NULL,
150 };
151 
152 /*-------------------------------------------------------------------------*/
153 
154 static struct timer_list	autoresume_timer;
155 
156 static void zero_autoresume(unsigned long _c)
157 {
158 	struct usb_composite_dev	*cdev = (void *)_c;
159 	struct usb_gadget		*g = cdev->gadget;
160 
161 	/* unconfigured devices can't issue wakeups */
162 	if (!cdev->config)
163 		return;
164 
165 	/* Normally the host would be woken up for something
166 	 * more significant than just a timer firing; likely
167 	 * because of some direct user request.
168 	 */
169 	if (g->speed != USB_SPEED_UNKNOWN) {
170 		int status = usb_gadget_wakeup(g);
171 		INFO(cdev, "%s --> %d\n", __func__, status);
172 	}
173 }
174 
175 static void zero_suspend(struct usb_composite_dev *cdev)
176 {
177 	if (cdev->gadget->speed == USB_SPEED_UNKNOWN)
178 		return;
179 
180 	if (autoresume) {
181 		if (max_autoresume &&
182 			(autoresume_step_ms > max_autoresume * 1000))
183 				autoresume_step_ms = autoresume * 1000;
184 
185 		mod_timer(&autoresume_timer, jiffies +
186 			msecs_to_jiffies(autoresume_step_ms));
187 		DBG(cdev, "suspend, wakeup in %d milliseconds\n",
188 			autoresume_step_ms);
189 
190 		autoresume_step_ms += autoresume_interval_ms;
191 	} else
192 		DBG(cdev, "%s\n", __func__);
193 }
194 
195 static void zero_resume(struct usb_composite_dev *cdev)
196 {
197 	DBG(cdev, "%s\n", __func__);
198 	del_timer(&autoresume_timer);
199 }
200 
201 /*-------------------------------------------------------------------------*/
202 
203 static struct usb_configuration loopback_driver = {
204 	.label          = "loopback",
205 	.bConfigurationValue = 2,
206 	.bmAttributes   = USB_CONFIG_ATT_SELFPOWER,
207 	/* .iConfiguration = DYNAMIC */
208 };
209 
210 static struct usb_function *func_ss;
211 static struct usb_function_instance *func_inst_ss;
212 
213 static int ss_config_setup(struct usb_configuration *c,
214 		const struct usb_ctrlrequest *ctrl)
215 {
216 	switch (ctrl->bRequest) {
217 	case 0x5b:
218 	case 0x5c:
219 		return func_ss->setup(func_ss, ctrl);
220 	default:
221 		return -EOPNOTSUPP;
222 	}
223 }
224 
225 static struct usb_configuration sourcesink_driver = {
226 	.label                  = "source/sink",
227 	.setup                  = ss_config_setup,
228 	.bConfigurationValue    = 3,
229 	.bmAttributes           = USB_CONFIG_ATT_SELFPOWER,
230 	/* .iConfiguration      = DYNAMIC */
231 };
232 
233 module_param_named(buflen, gzero_options.bulk_buflen, uint, 0);
234 module_param_named(pattern, gzero_options.pattern, uint, S_IRUGO|S_IWUSR);
235 MODULE_PARM_DESC(pattern, "0 = all zeroes, 1 = mod63, 2 = none");
236 
237 module_param_named(isoc_interval, gzero_options.isoc_interval, uint,
238 		S_IRUGO|S_IWUSR);
239 MODULE_PARM_DESC(isoc_interval, "1 - 16");
240 
241 module_param_named(isoc_maxpacket, gzero_options.isoc_maxpacket, uint,
242 		S_IRUGO|S_IWUSR);
243 MODULE_PARM_DESC(isoc_maxpacket, "0 - 1023 (fs), 0 - 1024 (hs/ss)");
244 
245 module_param_named(isoc_mult, gzero_options.isoc_mult, uint, S_IRUGO|S_IWUSR);
246 MODULE_PARM_DESC(isoc_mult, "0 - 2 (hs/ss only)");
247 
248 module_param_named(isoc_maxburst, gzero_options.isoc_maxburst, uint,
249 		S_IRUGO|S_IWUSR);
250 MODULE_PARM_DESC(isoc_maxburst, "0 - 15 (ss only)");
251 
252 static struct usb_function *func_lb;
253 static struct usb_function_instance *func_inst_lb;
254 
255 module_param_named(qlen, gzero_options.qlen, uint, S_IRUGO|S_IWUSR);
256 MODULE_PARM_DESC(qlen, "depth of loopback queue");
257 
258 static int zero_bind(struct usb_composite_dev *cdev)
259 {
260 	struct f_ss_opts	*ss_opts;
261 	struct f_lb_opts	*lb_opts;
262 	int			status;
263 
264 	/* Allocate string descriptor numbers ... note that string
265 	 * contents can be overridden by the composite_dev glue.
266 	 */
267 	status = usb_string_ids_tab(cdev, strings_dev);
268 	if (status < 0)
269 		return status;
270 
271 	device_desc.iManufacturer = strings_dev[USB_GADGET_MANUFACTURER_IDX].id;
272 	device_desc.iProduct = strings_dev[USB_GADGET_PRODUCT_IDX].id;
273 	device_desc.iSerialNumber = strings_dev[USB_GADGET_SERIAL_IDX].id;
274 
275 	setup_timer(&autoresume_timer, zero_autoresume, (unsigned long) cdev);
276 
277 	func_inst_ss = usb_get_function_instance("SourceSink");
278 	if (IS_ERR(func_inst_ss))
279 		return PTR_ERR(func_inst_ss);
280 
281 	ss_opts =  container_of(func_inst_ss, struct f_ss_opts, func_inst);
282 	ss_opts->pattern = gzero_options.pattern;
283 	ss_opts->isoc_interval = gzero_options.isoc_interval;
284 	ss_opts->isoc_maxpacket = gzero_options.isoc_maxpacket;
285 	ss_opts->isoc_mult = gzero_options.isoc_mult;
286 	ss_opts->isoc_maxburst = gzero_options.isoc_maxburst;
287 	ss_opts->bulk_buflen = gzero_options.bulk_buflen;
288 
289 	func_ss = usb_get_function(func_inst_ss);
290 	if (IS_ERR(func_ss)) {
291 		status = PTR_ERR(func_ss);
292 		goto err_put_func_inst_ss;
293 	}
294 
295 	func_inst_lb = usb_get_function_instance("Loopback");
296 	if (IS_ERR(func_inst_lb)) {
297 		status = PTR_ERR(func_inst_lb);
298 		goto err_put_func_ss;
299 	}
300 
301 	lb_opts = container_of(func_inst_lb, struct f_lb_opts, func_inst);
302 	lb_opts->bulk_buflen = gzero_options.bulk_buflen;
303 	lb_opts->qlen = gzero_options.qlen;
304 
305 	func_lb = usb_get_function(func_inst_lb);
306 	if (IS_ERR(func_lb)) {
307 		status = PTR_ERR(func_lb);
308 		goto err_put_func_inst_lb;
309 	}
310 
311 	sourcesink_driver.iConfiguration = strings_dev[USB_GZERO_SS_DESC].id;
312 	loopback_driver.iConfiguration = strings_dev[USB_GZERO_LB_DESC].id;
313 
314 	/* support autoresume for remote wakeup testing */
315 	sourcesink_driver.bmAttributes &= ~USB_CONFIG_ATT_WAKEUP;
316 	loopback_driver.bmAttributes &= ~USB_CONFIG_ATT_WAKEUP;
317 	sourcesink_driver.descriptors = NULL;
318 	loopback_driver.descriptors = NULL;
319 	if (autoresume) {
320 		sourcesink_driver.bmAttributes |= USB_CONFIG_ATT_WAKEUP;
321 		loopback_driver.bmAttributes |= USB_CONFIG_ATT_WAKEUP;
322 		autoresume_step_ms = autoresume * 1000;
323 	}
324 
325 	/* support OTG systems */
326 	if (gadget_is_otg(cdev->gadget)) {
327 		if (!otg_desc[0]) {
328 			struct usb_descriptor_header *usb_desc;
329 
330 			usb_desc = usb_otg_descriptor_alloc(cdev->gadget);
331 			if (!usb_desc) {
332 				status = -ENOMEM;
333 				goto err_conf_flb;
334 			}
335 			usb_otg_descriptor_init(cdev->gadget, usb_desc);
336 			otg_desc[0] = usb_desc;
337 			otg_desc[1] = NULL;
338 		}
339 		sourcesink_driver.descriptors = otg_desc;
340 		sourcesink_driver.bmAttributes |= USB_CONFIG_ATT_WAKEUP;
341 		loopback_driver.descriptors = otg_desc;
342 		loopback_driver.bmAttributes |= USB_CONFIG_ATT_WAKEUP;
343 	}
344 
345 	/* Register primary, then secondary configuration.  Note that
346 	 * SH3 only allows one config...
347 	 */
348 	if (loopdefault) {
349 		usb_add_config_only(cdev, &loopback_driver);
350 		usb_add_config_only(cdev, &sourcesink_driver);
351 	} else {
352 		usb_add_config_only(cdev, &sourcesink_driver);
353 		usb_add_config_only(cdev, &loopback_driver);
354 	}
355 	status = usb_add_function(&sourcesink_driver, func_ss);
356 	if (status)
357 		goto err_free_otg_desc;
358 
359 	usb_ep_autoconfig_reset(cdev->gadget);
360 	status = usb_add_function(&loopback_driver, func_lb);
361 	if (status)
362 		goto err_free_otg_desc;
363 
364 	usb_ep_autoconfig_reset(cdev->gadget);
365 	usb_composite_overwrite_options(cdev, &coverwrite);
366 
367 	INFO(cdev, "%s, version: " DRIVER_VERSION "\n", longname);
368 
369 	return 0;
370 
371 err_free_otg_desc:
372 	kfree(otg_desc[0]);
373 	otg_desc[0] = NULL;
374 err_conf_flb:
375 	usb_put_function(func_lb);
376 	func_lb = NULL;
377 err_put_func_inst_lb:
378 	usb_put_function_instance(func_inst_lb);
379 	func_inst_lb = NULL;
380 err_put_func_ss:
381 	usb_put_function(func_ss);
382 	func_ss = NULL;
383 err_put_func_inst_ss:
384 	usb_put_function_instance(func_inst_ss);
385 	func_inst_ss = NULL;
386 	return status;
387 }
388 
389 static int zero_unbind(struct usb_composite_dev *cdev)
390 {
391 	del_timer_sync(&autoresume_timer);
392 	if (!IS_ERR_OR_NULL(func_ss))
393 		usb_put_function(func_ss);
394 	usb_put_function_instance(func_inst_ss);
395 	if (!IS_ERR_OR_NULL(func_lb))
396 		usb_put_function(func_lb);
397 	usb_put_function_instance(func_inst_lb);
398 	kfree(otg_desc[0]);
399 	otg_desc[0] = NULL;
400 
401 	return 0;
402 }
403 
404 static struct usb_composite_driver zero_driver = {
405 	.name		= "zero",
406 	.dev		= &device_desc,
407 	.strings	= dev_strings,
408 	.max_speed	= USB_SPEED_SUPER,
409 	.bind		= zero_bind,
410 	.unbind		= zero_unbind,
411 	.suspend	= zero_suspend,
412 	.resume		= zero_resume,
413 };
414 
415 module_usb_composite_driver(zero_driver);
416 
417 MODULE_AUTHOR("David Brownell");
418 MODULE_LICENSE("GPL");
419