u-boot-brain/drivers/usb/gadget/usbstring.c
Tom Rini 83d290c56f SPDX: Convert all of our single license tags to Linux Kernel style
When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from.  So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry.  Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.

In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.

This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents.  There's also a few places where I found we did not have a tag
and have introduced one.

Signed-off-by: Tom Rini <trini@konsulko.com>
2018-05-07 09:34:12 -04:00

139 lines
3.3 KiB
C

// SPDX-License-Identifier: LGPL-2.1+
/*
* Copyright (C) 2003 David Brownell
*
* Ported to U-Boot by: Thomas Smits <ts.smits@gmail.com> and
* Remy Bohmer <linux@bohmer.net>
*/
#include <common.h>
#include <linux/errno.h>
#include <linux/usb/ch9.h>
#include <linux/usb/gadget.h>
#include <asm/unaligned.h>
static int utf8_to_utf16le(const char *s, __le16 *cp, unsigned len)
{
int count = 0;
u8 c;
u16 uchar;
/*
* this insists on correct encodings, though not minimal ones.
* BUT it currently rejects legit 4-byte UTF-8 code points,
* which need surrogate pairs. (Unicode 3.1 can use them.)
*/
while (len != 0 && (c = (u8) *s++) != 0) {
if ((c & 0x80)) {
/*
* 2-byte sequence:
* 00000yyyyyxxxxxx = 110yyyyy 10xxxxxx
*/
if ((c & 0xe0) == 0xc0) {
uchar = (c & 0x1f) << 6;
c = (u8) *s++;
if ((c & 0xc0) != 0x80)
goto fail;
c &= 0x3f;
uchar |= c;
/*
* 3-byte sequence (most CJKV characters):
* zzzzyyyyyyxxxxxx = 1110zzzz 10yyyyyy 10xxxxxx
*/
} else if ((c & 0xf0) == 0xe0) {
uchar = (c & 0x0f) << 12;
c = (u8) *s++;
if ((c & 0xc0) != 0x80)
goto fail;
c &= 0x3f;
uchar |= c << 6;
c = (u8) *s++;
if ((c & 0xc0) != 0x80)
goto fail;
c &= 0x3f;
uchar |= c;
/* no bogus surrogates */
if (0xd800 <= uchar && uchar <= 0xdfff)
goto fail;
/*
* 4-byte sequence (surrogate pairs, currently rare):
* 11101110wwwwzzzzyy + 110111yyyyxxxxxx
* = 11110uuu 10uuzzzz 10yyyyyy 10xxxxxx
* (uuuuu = wwww + 1)
* FIXME accept the surrogate code points (only)
*/
} else
goto fail;
} else
uchar = c;
put_unaligned_le16(uchar, cp++);
count++;
len--;
}
return count;
fail:
return -1;
}
/**
* usb_gadget_get_string - fill out a string descriptor
* @table: of c strings encoded using UTF-8
* @id: string id, from low byte of wValue in get string descriptor
* @buf: at least 256 bytes
*
* Finds the UTF-8 string matching the ID, and converts it into a
* string descriptor in utf16-le.
* Returns length of descriptor (always even) or negative errno
*
* If your driver needs stings in multiple languages, you'll probably
* "switch (wIndex) { ... }" in your ep0 string descriptor logic,
* using this routine after choosing which set of UTF-8 strings to use.
* Note that US-ASCII is a strict subset of UTF-8; any string bytes with
* the eighth bit set will be multibyte UTF-8 characters, not ISO-8859/1
* characters (which are also widely used in C strings).
*/
int
usb_gadget_get_string(struct usb_gadget_strings *table, int id, u8 *buf)
{
struct usb_string *s;
int len;
if (!table)
return -EINVAL;
/* descriptor 0 has the language id */
if (id == 0) {
buf[0] = 4;
buf[1] = USB_DT_STRING;
buf[2] = (u8) table->language;
buf[3] = (u8) (table->language >> 8);
return 4;
}
for (s = table->strings; s && s->s; s++)
if (s->id == id)
break;
/* unrecognized: stall. */
if (!s || !s->s)
return -EINVAL;
/* string descriptors have length, tag, then UTF16-LE text */
len = min((size_t) 126, strlen(s->s));
memset(buf + 2, 0, 2 * len); /* zero all the bytes */
len = utf8_to_utf16le(s->s, (__le16 *)&buf[2], len);
if (len < 0)
return -EINVAL;
buf[0] = (len + 1) * 2;
buf[1] = USB_DT_STRING;
return buf[0];
}