projects / u-boot.git / blame
| Commit | Line | Data |
|---|---|---|
| 83d290c5 | 1 | // SPDX-License-Identifier: LGPL-2.1+ |
| 23cd1385 RB |
2 | /* |
| 3 | * Copyright (C) 2003 David Brownell | |
| 4 | * | |
| a187559e | 5 | * Ported to U-Boot by: Thomas Smits <[email protected]> and |
| 23cd1385 RB |
6 | * Remy Bohmer <[email protected]> |
| 7 | */ | |
| 8 | ||
| 9 | #include <common.h> | |
| 1221ce45 | 10 | #include <linux/errno.h> |
| 23cd1385 RB |
11 | #include <linux/usb/ch9.h> |
| 12 | #include <linux/usb/gadget.h> | |
| 6777483f | 13 | #include <linux/utf.h> |
| 23cd1385 RB |
14 | |
| 15 | /** | |
| 16 | * usb_gadget_get_string - fill out a string descriptor | |
| 17 | * @table: of c strings encoded using UTF-8 | |
| 18 | * @id: string id, from low byte of wValue in get string descriptor | |
| 19 | * @buf: at least 256 bytes | |
| 20 | * | |
| 21 | * Finds the UTF-8 string matching the ID, and converts it into a | |
| 22 | * string descriptor in utf16-le. | |
| 23 | * Returns length of descriptor (always even) or negative errno | |
| 24 | * | |
| 25 | * If your driver needs stings in multiple languages, you'll probably | |
| 26 | * "switch (wIndex) { ... }" in your ep0 string descriptor logic, | |
| 27 | * using this routine after choosing which set of UTF-8 strings to use. | |
| 28 | * Note that US-ASCII is a strict subset of UTF-8; any string bytes with | |
| 29 | * the eighth bit set will be multibyte UTF-8 characters, not ISO-8859/1 | |
| 30 | * characters (which are also widely used in C strings). | |
| 31 | */ | |
| 32 | int | |
| 6142e0ae | 33 | usb_gadget_get_string(struct usb_gadget_strings *table, int id, u8 *buf) |
| 23cd1385 RB |
34 | { |
| 35 | struct usb_string *s; | |
| 36 | int len; | |
| 37 | ||
| 52d45012 RH |
38 | if (!table) |
| 39 | return -EINVAL; | |
| 40 | ||
| 23cd1385 RB |
41 | /* descriptor 0 has the language id */ |
| 42 | if (id == 0) { | |
| 6142e0ae VK |
43 | buf[0] = 4; |
| 44 | buf[1] = USB_DT_STRING; | |
| 45 | buf[2] = (u8) table->language; | |
| 46 | buf[3] = (u8) (table->language >> 8); | |
| 23cd1385 RB |
47 | return 4; |
| 48 | } | |
| 49 | for (s = table->strings; s && s->s; s++) | |
| 50 | if (s->id == id) | |
| 51 | break; | |
| 52 | ||
| 53 | /* unrecognized: stall. */ | |
| 54 | if (!s || !s->s) | |
| 55 | return -EINVAL; | |
| 56 | ||
| 57 | /* string descriptors have length, tag, then UTF16-LE text */ | |
| 6142e0ae VK |
58 | len = min((size_t) 126, strlen(s->s)); |
| 59 | memset(buf + 2, 0, 2 * len); /* zero all the bytes */ | |
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60 | len = utf8_to_utf16le(s->s, (__le16 *)&buf[2], len); |
| 61 | if (len < 0) | |
| 62 | return -EINVAL; | |
| 6142e0ae VK |
63 | buf[0] = (len + 1) * 2; |
| 64 | buf[1] = USB_DT_STRING; | |
| 65 | return buf[0]; | |
| 23cd1385 | 66 | } |