1 /*
2  * (C) Copyright 2015 Google, Inc
3  * Written by Simon Glass <sjg@chromium.org>
4  *
5  * SPDX-License-Identifier:	GPL-2.0+
6  */
7 
8 #include <common.h>
9 #include <dm.h>
10 #include <usb.h>
11 #include <dm/device-internal.h>
12 
13 DECLARE_GLOBAL_DATA_PTR;
14 
15 static int copy_to_unicode(char *buff, int length, const char *str)
16 {
17 	int ptr;
18 	int i;
19 
20 	if (length < 2)
21 		return 0;
22 	buff[1] = USB_DT_STRING;
23 	for (ptr = 2, i = 0; ptr + 1 < length && *str; i++, ptr += 2) {
24 		buff[ptr] = str[i];
25 		buff[ptr + 1] = 0;
26 	}
27 	buff[0] = ptr;
28 
29 	return ptr;
30 }
31 
32 static int usb_emul_get_string(struct usb_string *strings, int index,
33 			       char *buff, int length)
34 {
35 	if (index == 0) {
36 		char *desc = buff;
37 
38 		desc[0] = 4;
39 		desc[1] = USB_DT_STRING;
40 		desc[2] = 0x09;
41 		desc[3] = 0x14;
42 		return 4;
43 	} else if (strings) {
44 		struct usb_string *ptr;
45 
46 		for (ptr = strings; ptr->s; ptr++) {
47 			if (ptr->id == index)
48 				return copy_to_unicode(buff, length, ptr->s);
49 		}
50 	}
51 
52 	return -EINVAL;
53 }
54 
55 static struct usb_generic_descriptor **find_descriptor(
56 		struct usb_generic_descriptor **ptr, int type, int index)
57 {
58 	debug("%s: type=%x, index=%d\n", __func__, type, index);
59 	for (; *ptr; ptr++) {
60 		if ((*ptr)->bDescriptorType != type)
61 			continue;
62 		switch (type) {
63 		case USB_DT_CONFIG: {
64 			struct usb_config_descriptor *cdesc;
65 
66 			cdesc = (struct usb_config_descriptor *)*ptr;
67 			if (cdesc && cdesc->bConfigurationValue == index)
68 				return ptr;
69 			break;
70 		}
71 		default:
72 			return ptr;
73 		}
74 	}
75 	debug("%s: config ptr=%p\n", __func__, *ptr);
76 
77 	return ptr;
78 }
79 
80 static int usb_emul_get_descriptor(struct usb_dev_platdata *plat, int value,
81 				   void *buffer, int length)
82 {
83 	struct usb_generic_descriptor **ptr;
84 	int type = value >> 8;
85 	int index = value & 0xff;
86 	int upto, todo;
87 
88 	debug("%s: type=%d, index=%d, plat=%p\n", __func__, type, index, plat);
89 	if (type == USB_DT_STRING) {
90 		return usb_emul_get_string(plat->strings, index, buffer,
91 					   length);
92 	}
93 
94 	ptr = find_descriptor((struct usb_generic_descriptor **)plat->desc_list,
95 			      type, index);
96 	if (!ptr) {
97 		debug("%s: Could not find descriptor type %d, index %d\n",
98 		      __func__, type, index);
99 		return -ENOENT;
100 	}
101 	for (upto = 0; *ptr && upto < length; ptr++, upto += todo) {
102 		todo = min(length - upto, (int)(*ptr)->bLength);
103 
104 		memcpy(buffer + upto, *ptr, todo);
105 	}
106 
107 	return upto ? upto : length ? -EIO : 0;
108 }
109 
110 static int usb_emul_find_devnum(int devnum, struct udevice **emulp)
111 {
112 	struct udevice *dev;
113 	struct uclass *uc;
114 	int ret;
115 
116 	*emulp = NULL;
117 	ret = uclass_get(UCLASS_USB_EMUL, &uc);
118 	if (ret)
119 		return ret;
120 	uclass_foreach_dev(dev, uc) {
121 		struct usb_dev_platdata *udev = dev_get_parent_platdata(dev);
122 
123 		if (udev->devnum == devnum) {
124 			debug("%s: Found emulator '%s', addr %d\n", __func__,
125 			      dev->name, udev->devnum);
126 			*emulp = dev;
127 			return 0;
128 		}
129 	}
130 
131 	debug("%s: No emulator found, addr %d\n", __func__, devnum);
132 	return -ENOENT;
133 }
134 
135 int usb_emul_find(struct udevice *bus, ulong pipe, struct udevice **emulp)
136 {
137 	int devnum = usb_pipedevice(pipe);
138 
139 	return usb_emul_find_devnum(devnum, emulp);
140 }
141 
142 int usb_emul_find_for_dev(struct udevice *dev, struct udevice **emulp)
143 {
144 	struct usb_dev_platdata *udev = dev_get_parent_platdata(dev);
145 
146 	return usb_emul_find_devnum(udev->devnum, emulp);
147 }
148 
149 int usb_emul_control(struct udevice *emul, struct usb_device *udev,
150 		     unsigned long pipe, void *buffer, int length,
151 		     struct devrequest *setup)
152 {
153 	struct dm_usb_ops *ops = usb_get_emul_ops(emul);
154 	struct usb_dev_platdata *plat;
155 	int ret;
156 
157 	/* We permit getting the descriptor before we are probed */
158 	plat = dev_get_parent_platdata(emul);
159 	if (!ops->control)
160 		return -ENOSYS;
161 	debug("%s: dev=%s\n", __func__, emul->name);
162 	if (pipe == usb_rcvctrlpipe(udev, 0)) {
163 		switch (setup->request) {
164 		case USB_REQ_GET_DESCRIPTOR: {
165 			return usb_emul_get_descriptor(plat, setup->value,
166 						       buffer, length);
167 		}
168 		default:
169 			ret = device_probe(emul);
170 			if (ret)
171 				return ret;
172 			return ops->control(emul, udev, pipe, buffer, length,
173 					    setup);
174 		}
175 	} else if (pipe == usb_snddefctrl(udev)) {
176 		switch (setup->request) {
177 		case USB_REQ_SET_ADDRESS:
178 			debug("   ** set address %s %d\n", emul->name,
179 			      setup->value);
180 			plat->devnum = setup->value;
181 			return 0;
182 		default:
183 			debug("requestsend =%x\n", setup->request);
184 			break;
185 		}
186 	} else if (pipe == usb_sndctrlpipe(udev, 0)) {
187 		switch (setup->request) {
188 		case USB_REQ_SET_CONFIGURATION:
189 			plat->configno = setup->value;
190 			return 0;
191 		default:
192 			ret = device_probe(emul);
193 			if (ret)
194 				return ret;
195 			return ops->control(emul, udev, pipe, buffer, length,
196 					    setup);
197 		}
198 	}
199 	debug("pipe=%lx\n", pipe);
200 
201 	return -EIO;
202 }
203 
204 int usb_emul_bulk(struct udevice *emul, struct usb_device *udev,
205 		  unsigned long pipe, void *buffer, int length)
206 {
207 	struct dm_usb_ops *ops = usb_get_emul_ops(emul);
208 	int ret;
209 
210 	/* We permit getting the descriptor before we are probed */
211 	if (!ops->bulk)
212 		return -ENOSYS;
213 	debug("%s: dev=%s\n", __func__, emul->name);
214 	ret = device_probe(emul);
215 	if (ret)
216 		return ret;
217 	return ops->bulk(emul, udev, pipe, buffer, length);
218 }
219 
220 int usb_emul_int(struct udevice *emul, struct usb_device *udev,
221 		  unsigned long pipe, void *buffer, int length, int interval)
222 {
223 	struct dm_usb_ops *ops = usb_get_emul_ops(emul);
224 
225 	if (!ops->interrupt)
226 		return -ENOSYS;
227 	debug("%s: dev=%s\n", __func__, emul->name);
228 
229 	return ops->interrupt(emul, udev, pipe, buffer, length, interval);
230 }
231 
232 int usb_emul_setup_device(struct udevice *dev, int maxpacketsize,
233 			  struct usb_string *strings, void **desc_list)
234 {
235 	struct usb_dev_platdata *plat = dev_get_parent_platdata(dev);
236 	struct usb_generic_descriptor **ptr;
237 	struct usb_config_descriptor *cdesc;
238 	int upto;
239 
240 	plat->strings = strings;
241 	plat->desc_list = (struct usb_generic_descriptor **)desc_list;
242 
243 	/* Fill in wTotalLength for each configuration descriptor */
244 	ptr = plat->desc_list;
245 	for (cdesc = NULL, upto = 0; *ptr; upto += (*ptr)->bLength, ptr++) {
246 		debug("   - upto=%d, type=%d\n", upto, (*ptr)->bDescriptorType);
247 		if ((*ptr)->bDescriptorType == USB_DT_CONFIG) {
248 			if (cdesc) {
249 				cdesc->wTotalLength = upto;
250 				debug("%s: config %d length %d\n", __func__,
251 				      cdesc->bConfigurationValue,
252 				      cdesc->bLength);
253 			}
254 			cdesc = (struct usb_config_descriptor *)*ptr;
255 			upto = 0;
256 		}
257 	}
258 	if (cdesc) {
259 		cdesc->wTotalLength = upto;
260 		debug("%s: config %d length %d\n", __func__,
261 		      cdesc->bConfigurationValue, cdesc->wTotalLength);
262 	}
263 
264 	return 0;
265 }
266 
267 void usb_emul_reset(struct udevice *dev)
268 {
269 	struct usb_dev_platdata *plat = dev_get_parent_platdata(dev);
270 
271 	plat->devnum = 0;
272 	plat->configno = 0;
273 }
274 
275 UCLASS_DRIVER(usb_emul) = {
276 	.id		= UCLASS_USB_EMUL,
277 	.name		= "usb_emul",
278 	.post_bind	= dm_scan_fdt_dev,
279 	.per_child_auto_alloc_size = sizeof(struct usb_device),
280 	.per_child_platdata_auto_alloc_size = sizeof(struct usb_dev_platdata),
281 };
282