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/root.h>
12 #include <dm/device-internal.h>
13 
14 DECLARE_GLOBAL_DATA_PTR;
15 
16 static int copy_to_unicode(char *buff, int length, const char *str)
17 {
18 	int ptr;
19 	int i;
20 
21 	if (length < 2)
22 		return 0;
23 	buff[1] = USB_DT_STRING;
24 	for (ptr = 2, i = 0; ptr + 1 < length && *str; i++, ptr += 2) {
25 		buff[ptr] = str[i];
26 		buff[ptr + 1] = 0;
27 	}
28 	buff[0] = ptr;
29 
30 	return ptr;
31 }
32 
33 static int usb_emul_get_string(struct usb_string *strings, int index,
34 			       char *buff, int length)
35 {
36 	if (index == 0) {
37 		char *desc = buff;
38 
39 		desc[0] = 4;
40 		desc[1] = USB_DT_STRING;
41 		desc[2] = 0x09;
42 		desc[3] = 0x14;
43 		return 4;
44 	} else if (strings) {
45 		struct usb_string *ptr;
46 
47 		for (ptr = strings; ptr->s; ptr++) {
48 			if (ptr->id == index)
49 				return copy_to_unicode(buff, length, ptr->s);
50 		}
51 	}
52 
53 	return -EINVAL;
54 }
55 
56 static struct usb_generic_descriptor **find_descriptor(
57 		struct usb_generic_descriptor **ptr, int type, int index)
58 {
59 	debug("%s: type=%x, index=%d\n", __func__, type, index);
60 	for (; *ptr; ptr++) {
61 		if ((*ptr)->bDescriptorType != type)
62 			continue;
63 		switch (type) {
64 		case USB_DT_CONFIG: {
65 			struct usb_config_descriptor *cdesc;
66 
67 			cdesc = (struct usb_config_descriptor *)*ptr;
68 			if (cdesc && cdesc->bConfigurationValue == index)
69 				return ptr;
70 			break;
71 		}
72 		default:
73 			return ptr;
74 		}
75 	}
76 	debug("%s: config ptr=%p\n", __func__, *ptr);
77 
78 	return ptr;
79 }
80 
81 static int usb_emul_get_descriptor(struct usb_dev_platdata *plat, int value,
82 				   void *buffer, int length)
83 {
84 	struct usb_generic_descriptor **ptr;
85 	int type = value >> 8;
86 	int index = value & 0xff;
87 	int upto, todo;
88 
89 	debug("%s: type=%d, index=%d, plat=%p\n", __func__, type, index, plat);
90 	if (type == USB_DT_STRING) {
91 		return usb_emul_get_string(plat->strings, index, buffer,
92 					   length);
93 	}
94 
95 	ptr = find_descriptor((struct usb_generic_descriptor **)plat->desc_list,
96 			      type, index);
97 	if (!ptr) {
98 		debug("%s: Could not find descriptor type %d, index %d\n",
99 		      __func__, type, index);
100 		return -ENOENT;
101 	}
102 	for (upto = 0; *ptr && upto < length; ptr++, upto += todo) {
103 		todo = min(length - upto, (int)(*ptr)->bLength);
104 
105 		memcpy(buffer + upto, *ptr, todo);
106 	}
107 
108 	return upto ? upto : length ? -EIO : 0;
109 }
110 
111 static int usb_emul_find_devnum(int devnum, struct udevice **emulp)
112 {
113 	struct udevice *dev;
114 	struct uclass *uc;
115 	int ret;
116 
117 	*emulp = NULL;
118 	ret = uclass_get(UCLASS_USB_EMUL, &uc);
119 	if (ret)
120 		return ret;
121 	uclass_foreach_dev(dev, uc) {
122 		struct usb_dev_platdata *udev = dev_get_parent_platdata(dev);
123 
124 		if (udev->devnum == devnum) {
125 			debug("%s: Found emulator '%s', addr %d\n", __func__,
126 			      dev->name, udev->devnum);
127 			*emulp = dev;
128 			return 0;
129 		}
130 	}
131 
132 	debug("%s: No emulator found, addr %d\n", __func__, devnum);
133 	return -ENOENT;
134 }
135 
136 int usb_emul_find(struct udevice *bus, ulong pipe, struct udevice **emulp)
137 {
138 	int devnum = usb_pipedevice(pipe);
139 
140 	return usb_emul_find_devnum(devnum, emulp);
141 }
142 
143 int usb_emul_find_for_dev(struct udevice *dev, struct udevice **emulp)
144 {
145 	struct usb_dev_platdata *udev = dev_get_parent_platdata(dev);
146 
147 	return usb_emul_find_devnum(udev->devnum, emulp);
148 }
149 
150 int usb_emul_control(struct udevice *emul, struct usb_device *udev,
151 		     unsigned long pipe, void *buffer, int length,
152 		     struct devrequest *setup)
153 {
154 	struct dm_usb_ops *ops = usb_get_emul_ops(emul);
155 	struct usb_dev_platdata *plat;
156 	int ret;
157 
158 	/* We permit getting the descriptor before we are probed */
159 	plat = dev_get_parent_platdata(emul);
160 	if (!ops->control)
161 		return -ENOSYS;
162 	debug("%s: dev=%s\n", __func__, emul->name);
163 	if (pipe == usb_rcvctrlpipe(udev, 0)) {
164 		switch (setup->request) {
165 		case USB_REQ_GET_DESCRIPTOR: {
166 			return usb_emul_get_descriptor(plat, setup->value,
167 						       buffer, length);
168 		}
169 		default:
170 			ret = device_probe(emul);
171 			if (ret)
172 				return ret;
173 			return ops->control(emul, udev, pipe, buffer, length,
174 					    setup);
175 		}
176 	} else if (pipe == usb_snddefctrl(udev)) {
177 		switch (setup->request) {
178 		case USB_REQ_SET_ADDRESS:
179 			debug("   ** set address %s %d\n", emul->name,
180 			      setup->value);
181 			plat->devnum = setup->value;
182 			return 0;
183 		default:
184 			debug("requestsend =%x\n", setup->request);
185 			break;
186 		}
187 	} else if (pipe == usb_sndctrlpipe(udev, 0)) {
188 		switch (setup->request) {
189 		case USB_REQ_SET_CONFIGURATION:
190 			plat->configno = setup->value;
191 			return 0;
192 		default:
193 			ret = device_probe(emul);
194 			if (ret)
195 				return ret;
196 			return ops->control(emul, udev, pipe, buffer, length,
197 					    setup);
198 		}
199 	}
200 	debug("pipe=%lx\n", pipe);
201 
202 	return -EIO;
203 }
204 
205 int usb_emul_bulk(struct udevice *emul, struct usb_device *udev,
206 		  unsigned long pipe, void *buffer, int length)
207 {
208 	struct dm_usb_ops *ops = usb_get_emul_ops(emul);
209 	int ret;
210 
211 	/* We permit getting the descriptor before we are probed */
212 	if (!ops->bulk)
213 		return -ENOSYS;
214 	debug("%s: dev=%s\n", __func__, emul->name);
215 	ret = device_probe(emul);
216 	if (ret)
217 		return ret;
218 	return ops->bulk(emul, udev, pipe, buffer, length);
219 }
220 
221 int usb_emul_int(struct udevice *emul, struct usb_device *udev,
222 		  unsigned long pipe, void *buffer, int length, int interval)
223 {
224 	struct dm_usb_ops *ops = usb_get_emul_ops(emul);
225 
226 	if (!ops->interrupt)
227 		return -ENOSYS;
228 	debug("%s: dev=%s\n", __func__, emul->name);
229 
230 	return ops->interrupt(emul, udev, pipe, buffer, length, interval);
231 }
232 
233 int usb_emul_setup_device(struct udevice *dev, int maxpacketsize,
234 			  struct usb_string *strings, void **desc_list)
235 {
236 	struct usb_dev_platdata *plat = dev_get_parent_platdata(dev);
237 	struct usb_generic_descriptor **ptr;
238 	struct usb_config_descriptor *cdesc;
239 	int upto;
240 
241 	plat->strings = strings;
242 	plat->desc_list = (struct usb_generic_descriptor **)desc_list;
243 
244 	/* Fill in wTotalLength for each configuration descriptor */
245 	ptr = plat->desc_list;
246 	for (cdesc = NULL, upto = 0; *ptr; upto += (*ptr)->bLength, ptr++) {
247 		debug("   - upto=%d, type=%d\n", upto, (*ptr)->bDescriptorType);
248 		if ((*ptr)->bDescriptorType == USB_DT_CONFIG) {
249 			if (cdesc) {
250 				cdesc->wTotalLength = upto;
251 				debug("%s: config %d length %d\n", __func__,
252 				      cdesc->bConfigurationValue,
253 				      cdesc->bLength);
254 			}
255 			cdesc = (struct usb_config_descriptor *)*ptr;
256 			upto = 0;
257 		}
258 	}
259 	if (cdesc) {
260 		cdesc->wTotalLength = upto;
261 		debug("%s: config %d length %d\n", __func__,
262 		      cdesc->bConfigurationValue, cdesc->wTotalLength);
263 	}
264 
265 	return 0;
266 }
267 
268 int usb_emul_post_bind(struct udevice *dev)
269 {
270 	/* Scan the bus for devices */
271 	return dm_scan_fdt_node(dev, gd->fdt_blob, dev->of_offset, false);
272 }
273 
274 void usb_emul_reset(struct udevice *dev)
275 {
276 	struct usb_dev_platdata *plat = dev_get_parent_platdata(dev);
277 
278 	plat->devnum = 0;
279 	plat->configno = 0;
280 }
281 
282 UCLASS_DRIVER(usb_emul) = {
283 	.id		= UCLASS_USB_EMUL,
284 	.name		= "usb_emul",
285 	.post_bind	= usb_emul_post_bind,
286 	.per_child_auto_alloc_size = sizeof(struct usb_device),
287 	.per_child_platdata_auto_alloc_size = sizeof(struct usb_dev_platdata),
288 };
289