1 // SPDX-License-Identifier: GPL-2.0+
3  * usb/gadget/config.c -- simplify building config descriptors
16 #include <linux/usb/ch9.h>
17 #include <linux/usb/gadget.h>
18 #include <linux/usb/composite.h>
19 #include <linux/usb/otg.h>
22  * usb_descriptor_fillbuf - fill buffer with descriptors
28  * negative error code if they can't all be copied.  Useful when
39 	if (!src)  in usb_descriptor_fillbuf()
40 		return -EINVAL;  in usb_descriptor_fillbuf()
44 		unsigned		len = (*src)->bLength;  in usb_descriptor_fillbuf()
46 		if (len > buflen)  in usb_descriptor_fillbuf()
47 			return -EINVAL;  in usb_descriptor_fillbuf()
49 		buflen -= len;  in usb_descriptor_fillbuf()
52 	return dest - (u8 *)buf;  in usb_descriptor_fillbuf()
57  * usb_gadget_config_buf - builts a complete configuration descriptor
60  * @desc: Null-terminated vector of pointers to the descriptors (interface,
63  * @length: Length of buffer.  If this is not big enough to hold the
74  * resulting bDescriptorType value if USB_DT_OTHER_SPEED_CONFIG is needed.
87 	if (length < USB_DT_CONFIG_SIZE || !desc)  in usb_gadget_config_buf()
88 		return -EINVAL;  in usb_gadget_config_buf()
93 			length - USB_DT_CONFIG_SIZE, desc);  in usb_gadget_config_buf()
94 	if (len < 0)  in usb_gadget_config_buf()
97 	if (len > 0xffff)  in usb_gadget_config_buf()
98 		return -EINVAL;  in usb_gadget_config_buf()
101 	cp->bLength = USB_DT_CONFIG_SIZE;  in usb_gadget_config_buf()
102 	cp->bDescriptorType = USB_DT_CONFIG;  in usb_gadget_config_buf()
103 	cp->wTotalLength = cpu_to_le16(len);  in usb_gadget_config_buf()
104 	cp->bmAttributes |= USB_CONFIG_ATT_ONE;  in usb_gadget_config_buf()
110  * usb_copy_descriptors - copy a vector of USB descriptors
111  * @src: null-terminated vector to copy
114  * This makes a copy of a vector of USB descriptors.  Its primary use
132 		bytes += (*tmp)->bLength;  in usb_copy_descriptors()
136 	if (!mem)  in usb_copy_descriptors()
147 		memcpy(mem, *src, (*src)->bLength);  in usb_copy_descriptors()
150 		mem += (*src)->bLength;  in usb_copy_descriptors()
161 		struct usb_descriptor_header **hs,  in usb_assign_descriptors()  argument
165 	struct usb_gadget *g = f->config->cdev->gadget;  in usb_assign_descriptors()
167 	/* super-speed-plus descriptor falls back to super-speed one,  in usb_assign_descriptors()
168 	 * if such a descriptor was provided, thus avoiding a NULL  in usb_assign_descriptors()
169 	 * pointer dereference if a 5gbps capable gadget is used with  in usb_assign_descriptors()
172 	if (!ssp)  in usb_assign_descriptors()
175 	if (fs) {  in usb_assign_descriptors()
176 		f->fs_descriptors = usb_copy_descriptors(fs);  in usb_assign_descriptors()
177 		if (!f->fs_descriptors)  in usb_assign_descriptors()
180 	if (hs && gadget_is_dualspeed(g)) {  in usb_assign_descriptors()
181 		f->hs_descriptors = usb_copy_descriptors(hs);  in usb_assign_descriptors()
182 		if (!f->hs_descriptors)  in usb_assign_descriptors()
185 	if (ss && gadget_is_superspeed(g)) {  in usb_assign_descriptors()
186 		f->ss_descriptors = usb_copy_descriptors(ss);  in usb_assign_descriptors()
187 		if (!f->ss_descriptors)  in usb_assign_descriptors()
190 	if (ssp && gadget_is_superspeed_plus(g)) {  in usb_assign_descriptors()
191 		f->ssp_descriptors = usb_copy_descriptors(ssp);  in usb_assign_descriptors()
192 		if (!f->ssp_descriptors)  in usb_assign_descriptors()
198 	return -ENOMEM;  in usb_assign_descriptors()
204 	usb_free_descriptors(f->fs_descriptors);  in usb_free_all_descriptors()
205 	f->fs_descriptors = NULL;  in usb_free_all_descriptors()
206 	usb_free_descriptors(f->hs_descriptors);  in usb_free_all_descriptors()
207 	f->hs_descriptors = NULL;  in usb_free_all_descriptors()
208 	usb_free_descriptors(f->ss_descriptors);  in usb_free_all_descriptors()
209 	f->ss_descriptors = NULL;  in usb_free_all_descriptors()
210 	usb_free_descriptors(f->ssp_descriptors);  in usb_free_all_descriptors()
211 	f->ssp_descriptors = NULL;  in usb_free_all_descriptors()
221 	if (gadget->otg_caps && (gadget->otg_caps->otg_rev >= 0x0200))  in usb_otg_descriptor_alloc()
236 	struct usb_otg_caps *otg_caps = gadget->otg_caps;  in usb_otg_descriptor_init()
239 	if (!otg_desc)  in usb_otg_descriptor_init()
240 		return -EINVAL;  in usb_otg_descriptor_init()
242 	if (otg_caps && otg_caps->otg_rev) {  in usb_otg_descriptor_init()
243 		if (otg_caps->hnp_support)  in usb_otg_descriptor_init()
245 		if (otg_caps->srp_support)  in usb_otg_descriptor_init()
247 		if (otg_caps->adp_support && (otg_caps->otg_rev >= 0x0200))  in usb_otg_descriptor_init()
253 	if (otg_caps && (otg_caps->otg_rev >= 0x0200)) {  in usb_otg_descriptor_init()
255 		otg20_desc->bLength = sizeof(struct usb_otg20_descriptor);  in usb_otg_descriptor_init()
256 		otg20_desc->bDescriptorType = USB_DT_OTG;  in usb_otg_descriptor_init()
257 		otg20_desc->bmAttributes = otg_attributes;  in usb_otg_descriptor_init()
258 		otg20_desc->bcdOTG = cpu_to_le16(otg_caps->otg_rev);  in usb_otg_descriptor_init()
261 		otg1x_desc->bLength = sizeof(struct usb_otg_descriptor);  in usb_otg_descriptor_init()
262 		otg1x_desc->bDescriptorType = USB_DT_OTG;  in usb_otg_descriptor_init()
263 		otg1x_desc->bmAttributes = otg_attributes;  in usb_otg_descriptor_init()