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authorNiklas Cassel <cassel@kernel.org>2026-09-16 15:00:32 +0200
committerNiklas Cassel <cassel@kernel.org>2026-09-16 16:18:00 +0200
commit8d836581f9b1f57ceaa2b47654754ef1260b410b (patch)
tree1dbd4d0dfb99c2e238356cbe947e5b0be3e3a571 /drivers/usb/gadget/usbstring.c
downloadlinux-stable-8d836581f9b1f57ceaa2b47654754ef1260b410b.tar.gz
linux-stable-8d836581f9b1f57ceaa2b47654754ef1260b410b.zip
ata: libata-scsi: fix ata_dsm_trim_pages() kernel-docgrafted
make htmldocs fails with: Documentation/driver-api/libata:604: ./drivers/ata/libata-scsi.c:2301: ERROR: Unexpected indentation. [docutils] The Return: section of ata_dsm_trim_pages() ends its first sentence with a colon and continues with an indented bullet list. reStructuredText requires a blank line before an indented block, so docutils chokes on the list. Simply adding the missing blank line does not work either: Return: is a kernel-doc "special section", which is terminated by the first blank line, so the bullet list would end up in the Description section, detached from the sentence introducing it. Spell the two bounds out as prose instead, so that the Return: section stays self-contained. Documentation-only change. Fixes: e64e6b5dc867 ("ata: libata-scsi: scale DSM TRIM payload by MAX PAGES PER DSM COMMAND") Reported-by: Thomas Huth <thuth@redhat.com> Closes: https://lore.kernel.org/linux-ide/b0a0b8e8-cc4f-4c7b-8bc5-fee0712d405a@redhat.com/ Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Thomas Huth <thuth@redhat.com> Link: https://lore.kernel.org/r/20260916130031.29990-2-cassel@kernel.org Signed-off-by: Niklas Cassel <cassel@kernel.org>
Diffstat (limited to 'drivers/usb/gadget/usbstring.c')
-rw-r--r--drivers/usb/gadget/usbstring.c91
1 files changed, 91 insertions, 0 deletions
diff --git a/drivers/usb/gadget/usbstring.c b/drivers/usb/gadget/usbstring.c
new file mode 100644
index 000000000..37a2f1b61
--- /dev/null
+++ b/drivers/usb/gadget/usbstring.c
@@ -0,0 +1,91 @@
+// SPDX-License-Identifier: LGPL-2.1+
+/*
+ * Copyright (C) 2003 David Brownell
+ */
+
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/list.h>
+#include <linux/string.h>
+#include <linux/device.h>
+#include <linux/nls.h>
+
+#include <linux/usb/ch9.h>
+#include <linux/usb/gadget.h>
+
+
+/**
+ * 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, must be 16-bit aligned
+ *
+ * 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 (const struct usb_gadget_strings *table, int id, u8 *buf)
+{
+ struct usb_string *s;
+ int len;
+
+ /* 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_t(size_t, USB_MAX_STRING_LEN, strlen(s->s));
+ len = utf8s_to_utf16s(s->s, len, UTF16_LITTLE_ENDIAN,
+ (wchar_t *) &buf[2], USB_MAX_STRING_LEN);
+ if (len < 0)
+ return -EINVAL;
+ buf [0] = (len + 1) * 2;
+ buf [1] = USB_DT_STRING;
+ return buf [0];
+}
+EXPORT_SYMBOL_GPL(usb_gadget_get_string);
+
+/**
+ * usb_validate_langid - validate usb language identifiers
+ * @langid: usb language identifier
+ *
+ * Returns true for valid language identifier, otherwise false.
+ */
+bool usb_validate_langid(u16 langid)
+{
+ u16 primary_lang = langid & 0x3ff; /* bit [9:0] */
+ u16 sub_lang = langid >> 10; /* bit [15:10] */
+
+ switch (primary_lang) {
+ case 0:
+ case 0x62 ... 0xfe:
+ case 0x100 ... 0x3ff:
+ return false;
+ }
+ if (!sub_lang)
+ return false;
+
+ return true;
+}
+EXPORT_SYMBOL_GPL(usb_validate_langid);