15fd54aceSGreg Kroah-Hartman // SPDX-License-Identifier: GPL-2.0+
21da177e4SLinus Torvalds /*
31da177e4SLinus Torvalds * usb/gadget/config.c -- simplify building config descriptors
41da177e4SLinus Torvalds *
51da177e4SLinus Torvalds * Copyright (C) 2003 David Brownell
61da177e4SLinus Torvalds */
71da177e4SLinus Torvalds
81da177e4SLinus Torvalds #include <linux/errno.h>
95a0e3ad6STejun Heo #include <linux/slab.h>
101da177e4SLinus Torvalds #include <linux/kernel.h>
110ba16deaSSebastian Andrzej Siewior #include <linux/module.h>
121da177e4SLinus Torvalds #include <linux/list.h>
131da177e4SLinus Torvalds #include <linux/string.h>
141da177e4SLinus Torvalds #include <linux/device.h>
151da177e4SLinus Torvalds
165f848137SDavid Brownell #include <linux/usb/ch9.h>
179454a57aSDavid Brownell #include <linux/usb/gadget.h>
1810287baeSSebastian Andrzej Siewior #include <linux/usb/composite.h>
19d1606dfbSLi Jun #include <linux/usb/otg.h>
201da177e4SLinus Torvalds
211da177e4SLinus Torvalds /**
221da177e4SLinus Torvalds * usb_descriptor_fillbuf - fill buffer with descriptors
231da177e4SLinus Torvalds * @buf: Buffer to be filled
241da177e4SLinus Torvalds * @buflen: Size of buf
251da177e4SLinus Torvalds * @src: Array of descriptor pointers, terminated by null pointer.
261da177e4SLinus Torvalds *
271da177e4SLinus Torvalds * Copies descriptors into the buffer, returning the length or a
281da177e4SLinus Torvalds * negative error code if they can't all be copied. Useful when
291da177e4SLinus Torvalds * assembling descriptors for an associated set of interfaces used
301da177e4SLinus Torvalds * as part of configuring a composite device; or in other cases where
311da177e4SLinus Torvalds * sets of descriptors need to be marshaled.
321da177e4SLinus Torvalds */
331da177e4SLinus Torvalds int
usb_descriptor_fillbuf(void * buf,unsigned buflen,const struct usb_descriptor_header ** src)341da177e4SLinus Torvalds usb_descriptor_fillbuf(void *buf, unsigned buflen,
351da177e4SLinus Torvalds const struct usb_descriptor_header **src)
361da177e4SLinus Torvalds {
371da177e4SLinus Torvalds u8 *dest = buf;
381da177e4SLinus Torvalds
391da177e4SLinus Torvalds if (!src)
401da177e4SLinus Torvalds return -EINVAL;
411da177e4SLinus Torvalds
421da177e4SLinus Torvalds /* fill buffer from src[] until null descriptor ptr */
43a9475226SDavid Brownell for (; NULL != *src; src++) {
441da177e4SLinus Torvalds unsigned len = (*src)->bLength;
451da177e4SLinus Torvalds
461da177e4SLinus Torvalds if (len > buflen)
471da177e4SLinus Torvalds return -EINVAL;
481da177e4SLinus Torvalds memcpy(dest, *src, len);
491da177e4SLinus Torvalds buflen -= len;
501da177e4SLinus Torvalds dest += len;
511da177e4SLinus Torvalds }
521da177e4SLinus Torvalds return dest - (u8 *)buf;
531da177e4SLinus Torvalds }
540ba16deaSSebastian Andrzej Siewior EXPORT_SYMBOL_GPL(usb_descriptor_fillbuf);
551da177e4SLinus Torvalds
561da177e4SLinus Torvalds /**
571da177e4SLinus Torvalds * usb_gadget_config_buf - builts a complete configuration descriptor
581da177e4SLinus Torvalds * @config: Header for the descriptor, including characteristics such
591da177e4SLinus Torvalds * as power requirements and number of interfaces.
601da177e4SLinus Torvalds * @desc: Null-terminated vector of pointers to the descriptors (interface,
611da177e4SLinus Torvalds * endpoint, etc) defining all functions in this device configuration.
621da177e4SLinus Torvalds * @buf: Buffer for the resulting configuration descriptor.
631da177e4SLinus Torvalds * @length: Length of buffer. If this is not big enough to hold the
641da177e4SLinus Torvalds * entire configuration descriptor, an error code will be returned.
651da177e4SLinus Torvalds *
661da177e4SLinus Torvalds * This copies descriptors into the response buffer, building a descriptor
671da177e4SLinus Torvalds * for that configuration. It returns the buffer length or a negative
681da177e4SLinus Torvalds * status code. The config.wTotalLength field is set to match the length
691da177e4SLinus Torvalds * of the result, but other descriptor fields (including power usage and
701da177e4SLinus Torvalds * interface count) must be set by the caller.
711da177e4SLinus Torvalds *
721da177e4SLinus Torvalds * Gadget drivers could use this when constructing a config descriptor
731da177e4SLinus Torvalds * in response to USB_REQ_GET_DESCRIPTOR. They will need to patch the
741da177e4SLinus Torvalds * resulting bDescriptorType value if USB_DT_OTHER_SPEED_CONFIG is needed.
751da177e4SLinus Torvalds */
usb_gadget_config_buf(const struct usb_config_descriptor * config,void * buf,unsigned length,const struct usb_descriptor_header ** desc)761da177e4SLinus Torvalds int usb_gadget_config_buf(
771da177e4SLinus Torvalds const struct usb_config_descriptor *config,
781da177e4SLinus Torvalds void *buf,
791da177e4SLinus Torvalds unsigned length,
801da177e4SLinus Torvalds const struct usb_descriptor_header **desc
811da177e4SLinus Torvalds )
821da177e4SLinus Torvalds {
831da177e4SLinus Torvalds struct usb_config_descriptor *cp = buf;
841da177e4SLinus Torvalds int len;
851da177e4SLinus Torvalds
861da177e4SLinus Torvalds /* config descriptor first */
871da177e4SLinus Torvalds if (length < USB_DT_CONFIG_SIZE || !desc)
881da177e4SLinus Torvalds return -EINVAL;
891da177e4SLinus Torvalds *cp = *config;
901da177e4SLinus Torvalds
911da177e4SLinus Torvalds /* then interface/endpoint/class/vendor/... */
921da177e4SLinus Torvalds len = usb_descriptor_fillbuf(USB_DT_CONFIG_SIZE + (u8 *)buf,
931da177e4SLinus Torvalds length - USB_DT_CONFIG_SIZE, desc);
941da177e4SLinus Torvalds if (len < 0)
951da177e4SLinus Torvalds return len;
961da177e4SLinus Torvalds len += USB_DT_CONFIG_SIZE;
971da177e4SLinus Torvalds if (len > 0xffff)
981da177e4SLinus Torvalds return -EINVAL;
991da177e4SLinus Torvalds
1001da177e4SLinus Torvalds /* patch up the config descriptor */
1011da177e4SLinus Torvalds cp->bLength = USB_DT_CONFIG_SIZE;
1021da177e4SLinus Torvalds cp->bDescriptorType = USB_DT_CONFIG;
1031da177e4SLinus Torvalds cp->wTotalLength = cpu_to_le16(len);
1041da177e4SLinus Torvalds cp->bmAttributes |= USB_CONFIG_ATT_ONE;
1051da177e4SLinus Torvalds return len;
1061da177e4SLinus Torvalds }
1070ba16deaSSebastian Andrzej Siewior EXPORT_SYMBOL_GPL(usb_gadget_config_buf);
1081da177e4SLinus Torvalds
109a4c39c41SDavid Brownell /**
110a4c39c41SDavid Brownell * usb_copy_descriptors - copy a vector of USB descriptors
111a4c39c41SDavid Brownell * @src: null-terminated vector to copy
112a4c39c41SDavid Brownell * Context: initialization code, which may sleep
113a4c39c41SDavid Brownell *
114a4c39c41SDavid Brownell * This makes a copy of a vector of USB descriptors. Its primary use
115a4c39c41SDavid Brownell * is to support usb_function objects which can have multiple copies,
116a4c39c41SDavid Brownell * each needing different descriptors. Functions may have static
117a4c39c41SDavid Brownell * tables of descriptors, which are used as templates and customized
118a4c39c41SDavid Brownell * with identifiers (for interfaces, strings, endpoints, and more)
119a4c39c41SDavid Brownell * as needed by a given function instance.
120a4c39c41SDavid Brownell */
12128824b18SMichal Nazarewicz struct usb_descriptor_header **
usb_copy_descriptors(struct usb_descriptor_header ** src)122a4c39c41SDavid Brownell usb_copy_descriptors(struct usb_descriptor_header **src)
123a4c39c41SDavid Brownell {
124a4c39c41SDavid Brownell struct usb_descriptor_header **tmp;
125a4c39c41SDavid Brownell unsigned bytes;
126a4c39c41SDavid Brownell unsigned n_desc;
127a4c39c41SDavid Brownell void *mem;
128a4c39c41SDavid Brownell struct usb_descriptor_header **ret;
129a4c39c41SDavid Brownell
130a4c39c41SDavid Brownell /* count descriptors and their sizes; then add vector size */
131a4c39c41SDavid Brownell for (bytes = 0, n_desc = 0, tmp = src; *tmp; tmp++, n_desc++)
132a4c39c41SDavid Brownell bytes += (*tmp)->bLength;
133a4c39c41SDavid Brownell bytes += (n_desc + 1) * sizeof(*tmp);
134a4c39c41SDavid Brownell
135a4c39c41SDavid Brownell mem = kmalloc(bytes, GFP_KERNEL);
136a4c39c41SDavid Brownell if (!mem)
137a4c39c41SDavid Brownell return NULL;
138a4c39c41SDavid Brownell
139a4c39c41SDavid Brownell /* fill in pointers starting at "tmp",
140a4c39c41SDavid Brownell * to descriptors copied starting at "mem";
141a4c39c41SDavid Brownell * and return "ret"
142a4c39c41SDavid Brownell */
143a4c39c41SDavid Brownell tmp = mem;
144a4c39c41SDavid Brownell ret = mem;
145a4c39c41SDavid Brownell mem += (n_desc + 1) * sizeof(*tmp);
146a4c39c41SDavid Brownell while (*src) {
147a4c39c41SDavid Brownell memcpy(mem, *src, (*src)->bLength);
148a4c39c41SDavid Brownell *tmp = mem;
149a4c39c41SDavid Brownell tmp++;
150a4c39c41SDavid Brownell mem += (*src)->bLength;
151a4c39c41SDavid Brownell src++;
152a4c39c41SDavid Brownell }
153a4c39c41SDavid Brownell *tmp = NULL;
154a4c39c41SDavid Brownell
155a4c39c41SDavid Brownell return ret;
156a4c39c41SDavid Brownell }
1570ba16deaSSebastian Andrzej Siewior EXPORT_SYMBOL_GPL(usb_copy_descriptors);
15810287baeSSebastian Andrzej Siewior
usb_assign_descriptors(struct usb_function * f,struct usb_descriptor_header ** fs,struct usb_descriptor_header ** hs,struct usb_descriptor_header ** ss,struct usb_descriptor_header ** ssp)15910287baeSSebastian Andrzej Siewior int usb_assign_descriptors(struct usb_function *f,
16010287baeSSebastian Andrzej Siewior struct usb_descriptor_header **fs,
16110287baeSSebastian Andrzej Siewior struct usb_descriptor_header **hs,
162eaef50c7SJohn Youn struct usb_descriptor_header **ss,
163eaef50c7SJohn Youn struct usb_descriptor_header **ssp)
16410287baeSSebastian Andrzej Siewior {
165032e2880SMaciej Żenczykowski /* super-speed-plus descriptor falls back to super-speed one,
166032e2880SMaciej Żenczykowski * if such a descriptor was provided, thus avoiding a NULL
167032e2880SMaciej Żenczykowski * pointer dereference if a 5gbps capable gadget is used with
168032e2880SMaciej Żenczykowski * a 10gbps capable config (device port + cable + host port)
169032e2880SMaciej Żenczykowski */
170032e2880SMaciej Żenczykowski if (!ssp)
171032e2880SMaciej Żenczykowski ssp = ss;
172032e2880SMaciej Żenczykowski
17310287baeSSebastian Andrzej Siewior if (fs) {
17410287baeSSebastian Andrzej Siewior f->fs_descriptors = usb_copy_descriptors(fs);
17510287baeSSebastian Andrzej Siewior if (!f->fs_descriptors)
17610287baeSSebastian Andrzej Siewior goto err;
17710287baeSSebastian Andrzej Siewior }
178*4dfdd90bSLinyu Yuan if (hs) {
17910287baeSSebastian Andrzej Siewior f->hs_descriptors = usb_copy_descriptors(hs);
18010287baeSSebastian Andrzej Siewior if (!f->hs_descriptors)
18110287baeSSebastian Andrzej Siewior goto err;
18210287baeSSebastian Andrzej Siewior }
183*4dfdd90bSLinyu Yuan if (ss) {
18410287baeSSebastian Andrzej Siewior f->ss_descriptors = usb_copy_descriptors(ss);
18510287baeSSebastian Andrzej Siewior if (!f->ss_descriptors)
18610287baeSSebastian Andrzej Siewior goto err;
18710287baeSSebastian Andrzej Siewior }
188*4dfdd90bSLinyu Yuan if (ssp) {
189f5c61225SJohn Youn f->ssp_descriptors = usb_copy_descriptors(ssp);
190f5c61225SJohn Youn if (!f->ssp_descriptors)
191f5c61225SJohn Youn goto err;
192f5c61225SJohn Youn }
19310287baeSSebastian Andrzej Siewior return 0;
19410287baeSSebastian Andrzej Siewior err:
19510287baeSSebastian Andrzej Siewior usb_free_all_descriptors(f);
19610287baeSSebastian Andrzej Siewior return -ENOMEM;
19710287baeSSebastian Andrzej Siewior }
19810287baeSSebastian Andrzej Siewior EXPORT_SYMBOL_GPL(usb_assign_descriptors);
19910287baeSSebastian Andrzej Siewior
usb_free_all_descriptors(struct usb_function * f)20010287baeSSebastian Andrzej Siewior void usb_free_all_descriptors(struct usb_function *f)
20110287baeSSebastian Andrzej Siewior {
20210287baeSSebastian Andrzej Siewior usb_free_descriptors(f->fs_descriptors);
20343c4cab0SHemant Kumar f->fs_descriptors = NULL;
20410287baeSSebastian Andrzej Siewior usb_free_descriptors(f->hs_descriptors);
20543c4cab0SHemant Kumar f->hs_descriptors = NULL;
20610287baeSSebastian Andrzej Siewior usb_free_descriptors(f->ss_descriptors);
20743c4cab0SHemant Kumar f->ss_descriptors = NULL;
208f5c61225SJohn Youn usb_free_descriptors(f->ssp_descriptors);
20943c4cab0SHemant Kumar f->ssp_descriptors = NULL;
21010287baeSSebastian Andrzej Siewior }
21110287baeSSebastian Andrzej Siewior EXPORT_SYMBOL_GPL(usb_free_all_descriptors);
212d1606dfbSLi Jun
usb_otg_descriptor_alloc(struct usb_gadget * gadget)213d1606dfbSLi Jun struct usb_descriptor_header *usb_otg_descriptor_alloc(
214d1606dfbSLi Jun struct usb_gadget *gadget)
215d1606dfbSLi Jun {
216d1606dfbSLi Jun struct usb_descriptor_header *otg_desc;
217d1606dfbSLi Jun unsigned length = 0;
218d1606dfbSLi Jun
219d1606dfbSLi Jun if (gadget->otg_caps && (gadget->otg_caps->otg_rev >= 0x0200))
220d1606dfbSLi Jun length = sizeof(struct usb_otg20_descriptor);
221d1606dfbSLi Jun else
222d1606dfbSLi Jun length = sizeof(struct usb_otg_descriptor);
223d1606dfbSLi Jun
224d1606dfbSLi Jun otg_desc = kzalloc(length, GFP_KERNEL);
225d1606dfbSLi Jun return otg_desc;
226d1606dfbSLi Jun }
227d1606dfbSLi Jun EXPORT_SYMBOL_GPL(usb_otg_descriptor_alloc);
228d1606dfbSLi Jun
usb_otg_descriptor_init(struct usb_gadget * gadget,struct usb_descriptor_header * otg_desc)229d1606dfbSLi Jun int usb_otg_descriptor_init(struct usb_gadget *gadget,
230d1606dfbSLi Jun struct usb_descriptor_header *otg_desc)
231d1606dfbSLi Jun {
232d1606dfbSLi Jun struct usb_otg_descriptor *otg1x_desc;
233d1606dfbSLi Jun struct usb_otg20_descriptor *otg20_desc;
234d1606dfbSLi Jun struct usb_otg_caps *otg_caps = gadget->otg_caps;
235d1606dfbSLi Jun u8 otg_attributes = 0;
236d1606dfbSLi Jun
237d1606dfbSLi Jun if (!otg_desc)
238d1606dfbSLi Jun return -EINVAL;
239d1606dfbSLi Jun
240d1606dfbSLi Jun if (otg_caps && otg_caps->otg_rev) {
241d1606dfbSLi Jun if (otg_caps->hnp_support)
242d1606dfbSLi Jun otg_attributes |= USB_OTG_HNP;
243d1606dfbSLi Jun if (otg_caps->srp_support)
244d1606dfbSLi Jun otg_attributes |= USB_OTG_SRP;
245d1606dfbSLi Jun if (otg_caps->adp_support && (otg_caps->otg_rev >= 0x0200))
246d1606dfbSLi Jun otg_attributes |= USB_OTG_ADP;
247d1606dfbSLi Jun } else {
248d1606dfbSLi Jun otg_attributes = USB_OTG_SRP | USB_OTG_HNP;
249d1606dfbSLi Jun }
250d1606dfbSLi Jun
251d1606dfbSLi Jun if (otg_caps && (otg_caps->otg_rev >= 0x0200)) {
252d1606dfbSLi Jun otg20_desc = (struct usb_otg20_descriptor *)otg_desc;
253d1606dfbSLi Jun otg20_desc->bLength = sizeof(struct usb_otg20_descriptor);
254d1606dfbSLi Jun otg20_desc->bDescriptorType = USB_DT_OTG;
255d1606dfbSLi Jun otg20_desc->bmAttributes = otg_attributes;
256d1606dfbSLi Jun otg20_desc->bcdOTG = cpu_to_le16(otg_caps->otg_rev);
257d1606dfbSLi Jun } else {
258d1606dfbSLi Jun otg1x_desc = (struct usb_otg_descriptor *)otg_desc;
259d1606dfbSLi Jun otg1x_desc->bLength = sizeof(struct usb_otg_descriptor);
260d1606dfbSLi Jun otg1x_desc->bDescriptorType = USB_DT_OTG;
261d1606dfbSLi Jun otg1x_desc->bmAttributes = otg_attributes;
262d1606dfbSLi Jun }
263d1606dfbSLi Jun
264d1606dfbSLi Jun return 0;
265d1606dfbSLi Jun }
266d1606dfbSLi Jun EXPORT_SYMBOL_GPL(usb_otg_descriptor_init);
267