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 int usb_emul_find(struct udevice *bus, ulong pipe, struct udevice **emulp)
112 {
113 	int devnum = usb_pipedevice(pipe);
114 	struct udevice *dev;
115 	struct uclass *uc;
116 	int ret;
117 
118 	*emulp = NULL;
119 	ret = uclass_get(UCLASS_USB_EMUL, &uc);
120 	if (ret)
121 		return ret;
122 	uclass_foreach_dev(dev, uc) {
123 		struct usb_dev_platdata *udev = dev_get_parent_platdata(dev);
124 
125 		if (udev->devnum == devnum) {
126 			debug("%s: Found emulator '%s', addr %d\n", __func__,
127 			      dev->name, udev->devnum);
128 			*emulp = dev;
129 			return 0;
130 		}
131 	}
132 
133 	debug("%s: No emulator found, addr %d\n", __func__, devnum);
134 	return -ENOENT;
135 }
136 
137 int usb_emul_control(struct udevice *emul, struct usb_device *udev,
138 		     unsigned long pipe, void *buffer, int length,
139 		     struct devrequest *setup)
140 {
141 	struct dm_usb_ops *ops = usb_get_emul_ops(emul);
142 	struct usb_dev_platdata *plat;
143 	int ret;
144 
145 	/* We permit getting the descriptor before we are probed */
146 	plat = dev_get_parent_platdata(emul);
147 	if (!ops->control)
148 		return -ENOSYS;
149 	debug("%s: dev=%s\n", __func__, emul->name);
150 	if (pipe == usb_rcvctrlpipe(udev, 0)) {
151 		switch (setup->request) {
152 		case USB_REQ_GET_DESCRIPTOR: {
153 			return usb_emul_get_descriptor(plat, setup->value,
154 						       buffer, length);
155 		}
156 		default:
157 			ret = device_probe(emul);
158 			if (ret)
159 				return ret;
160 			return ops->control(emul, udev, pipe, buffer, length,
161 					    setup);
162 		}
163 	} else if (pipe == usb_snddefctrl(udev)) {
164 		switch (setup->request) {
165 		case USB_REQ_SET_ADDRESS:
166 			debug("   ** set address %s %d\n", emul->name,
167 			      setup->value);
168 			plat->devnum = setup->value;
169 			return 0;
170 		default:
171 			debug("requestsend =%x\n", setup->request);
172 			break;
173 		}
174 	} else if (pipe == usb_sndctrlpipe(udev, 0)) {
175 		switch (setup->request) {
176 		case USB_REQ_SET_CONFIGURATION:
177 			plat->configno = setup->value;
178 			return 0;
179 		default:
180 			ret = device_probe(emul);
181 			if (ret)
182 				return ret;
183 			return ops->control(emul, udev, pipe, buffer, length,
184 					    setup);
185 		}
186 	}
187 	debug("pipe=%lx\n", pipe);
188 
189 	return -EIO;
190 }
191 
192 int usb_emul_bulk(struct udevice *emul, struct usb_device *udev,
193 		  unsigned long pipe, void *buffer, int length)
194 {
195 	struct dm_usb_ops *ops = usb_get_emul_ops(emul);
196 	int ret;
197 
198 	/* We permit getting the descriptor before we are probed */
199 	if (!ops->bulk)
200 		return -ENOSYS;
201 	debug("%s: dev=%s\n", __func__, emul->name);
202 	ret = device_probe(emul);
203 	if (ret)
204 		return ret;
205 	return ops->bulk(emul, udev, pipe, buffer, length);
206 }
207 
208 int usb_emul_setup_device(struct udevice *dev, int maxpacketsize,
209 			  struct usb_string *strings, void **desc_list)
210 {
211 	struct usb_dev_platdata *plat = dev_get_parent_platdata(dev);
212 	struct usb_generic_descriptor **ptr;
213 	struct usb_config_descriptor *cdesc;
214 	int upto;
215 
216 	plat->strings = strings;
217 	plat->desc_list = (struct usb_generic_descriptor **)desc_list;
218 
219 	/* Fill in wTotalLength for each configuration descriptor */
220 	ptr = plat->desc_list;
221 	for (cdesc = NULL, upto = 0; *ptr; upto += (*ptr)->bLength, ptr++) {
222 		debug("   - upto=%d, type=%d\n", upto, (*ptr)->bDescriptorType);
223 		if ((*ptr)->bDescriptorType == USB_DT_CONFIG) {
224 			if (cdesc) {
225 				cdesc->wTotalLength = upto;
226 				debug("%s: config %d length %d\n", __func__,
227 				      cdesc->bConfigurationValue,
228 				      cdesc->bLength);
229 			}
230 			cdesc = (struct usb_config_descriptor *)*ptr;
231 			upto = 0;
232 		}
233 	}
234 	if (cdesc) {
235 		cdesc->wTotalLength = upto;
236 		debug("%s: config %d length %d\n", __func__,
237 		      cdesc->bConfigurationValue, cdesc->wTotalLength);
238 	}
239 
240 	return 0;
241 }
242 
243 int usb_emul_post_bind(struct udevice *dev)
244 {
245 	/* Scan the bus for devices */
246 	return dm_scan_fdt_node(dev, gd->fdt_blob, dev->of_offset, false);
247 }
248 
249 void usb_emul_reset(struct udevice *dev)
250 {
251 	struct usb_dev_platdata *plat = dev_get_parent_platdata(dev);
252 
253 	plat->devnum = 0;
254 	plat->configno = 0;
255 }
256 
257 UCLASS_DRIVER(usb_emul) = {
258 	.id		= UCLASS_USB_EMUL,
259 	.name		= "usb_emul",
260 	.post_bind	= usb_emul_post_bind,
261 	.per_child_auto_alloc_size = sizeof(struct usb_device),
262 	.per_child_platdata_auto_alloc_size = sizeof(struct usb_dev_platdata),
263 };
264