[PATCH v1 2/2] wmi: use generic UUID library

From: Andy Shevchenko
Date: Thu Apr 07 2016 - 13:01:10 EST


Instead of opencoding let's use generic UUID library functions here.

Cc: Darren Hart <dvhart@xxxxxxxxxxxxxxx>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
---
drivers/platform/x86/wmi.c | 104 ++++++---------------------------------------
1 file changed, 13 insertions(+), 91 deletions(-)

diff --git a/drivers/platform/x86/wmi.c b/drivers/platform/x86/wmi.c
index eb391a2..ceeb8c1 100644
--- a/drivers/platform/x86/wmi.c
+++ b/drivers/platform/x86/wmi.c
@@ -37,6 +37,7 @@
#include <linux/acpi.h>
#include <linux/slab.h>
#include <linux/module.h>
+#include <linux/uuid.h>

ACPI_MODULE_NAME("wmi");
MODULE_AUTHOR("Carlos Corbacho");
@@ -115,100 +116,21 @@ static struct acpi_driver acpi_wmi_driver = {
* GUID parsing functions
*/

-/**
- * wmi_parse_hexbyte - Convert a ASCII hex number to a byte
- * @src: Pointer to at least 2 characters to convert.
- *
- * Convert a two character ASCII hex string to a number.
- *
- * Return: 0-255 Success, the byte was parsed correctly
- * -1 Error, an invalid character was supplied
- */
-static int wmi_parse_hexbyte(const u8 *src)
-{
- int h;
- int value;
-
- /* high part */
- h = value = hex_to_bin(src[0]);
- if (value < 0)
- return -1;
-
- /* low part */
- value = hex_to_bin(src[1]);
- if (value >= 0)
- return (h << 4) | value;
- return -1;
-}
-
-/**
- * wmi_swap_bytes - Rearrange GUID bytes to match GUID binary
- * @src: Memory block holding binary GUID (16 bytes)
- * @dest: Memory block to hold byte swapped binary GUID (16 bytes)
- *
- * Byte swap a binary GUID to match it's real GUID value
- */
-static void wmi_swap_bytes(u8 *src, u8 *dest)
-{
- int i;
-
- for (i = 0; i <= 3; i++)
- memcpy(dest + i, src + (3 - i), 1);
-
- for (i = 0; i <= 1; i++)
- memcpy(dest + 4 + i, src + (5 - i), 1);
-
- for (i = 0; i <= 1; i++)
- memcpy(dest + 6 + i, src + (7 - i), 1);
-
- memcpy(dest + 8, src + 8, 8);
-}
-
-/**
- * wmi_parse_guid - Convert GUID from ASCII to binary
- * @src: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
- * @dest: Memory block to hold binary GUID (16 bytes)
- *
- * N.B. The GUID need not be NULL terminated.
- *
- * Return: 'true' @dest contains binary GUID
- * 'false' @dest contents are undefined
- */
-static bool wmi_parse_guid(const u8 *src, u8 *dest)
-{
- static const int size[] = { 4, 2, 2, 2, 6 };
- int i, j, v;
-
- if (src[8] != '-' || src[13] != '-' ||
- src[18] != '-' || src[23] != '-')
- return false;
-
- for (j = 0; j < 5; j++, src++) {
- for (i = 0; i < size[j]; i++, src += 2, *dest++ = v) {
- v = wmi_parse_hexbyte(src);
- if (v < 0)
- return false;
- }
- }
-
- return true;
-}
-
static bool find_guid(const char *guid_string, struct wmi_block **out)
{
- char tmp[16], guid_input[16];
+ uuid_le guid_input;
struct wmi_block *wblock;
struct guid_block *block;
struct list_head *p;

- wmi_parse_guid(guid_string, tmp);
- wmi_swap_bytes(tmp, guid_input);
+ if (uuid_le_to_bin(guid_string, &guid_input))
+ return false;

list_for_each(p, &wmi_block_list) {
wblock = list_entry(p, struct wmi_block, list);
block = &wblock->gblock;

- if (memcmp(block->guid, guid_input, 16) == 0) {
+ if (memcmp(block->guid, &guid_input, 16) == 0) {
if (out)
*out = wblock;
return true;
@@ -498,20 +420,20 @@ wmi_notify_handler handler, void *data)
{
struct wmi_block *block;
acpi_status status = AE_NOT_EXIST;
- char tmp[16], guid_input[16];
+ uuid_le guid_input;
struct list_head *p;

if (!guid || !handler)
return AE_BAD_PARAMETER;

- wmi_parse_guid(guid, tmp);
- wmi_swap_bytes(tmp, guid_input);
+ if (uuid_le_to_bin(guid, &guid_input))
+ return AE_BAD_PARAMETER;

list_for_each(p, &wmi_block_list) {
acpi_status wmi_status;
block = list_entry(p, struct wmi_block, list);

- if (memcmp(block->gblock.guid, guid_input, 16) == 0) {
+ if (memcmp(block->gblock.guid, &guid_input, 16) == 0) {
if (block->handler &&
block->handler != wmi_notify_debug)
return AE_ALREADY_ACQUIRED;
@@ -539,20 +461,20 @@ acpi_status wmi_remove_notify_handler(const char *guid)
{
struct wmi_block *block;
acpi_status status = AE_NOT_EXIST;
- char tmp[16], guid_input[16];
+ uuid_le guid_input;
struct list_head *p;

if (!guid)
return AE_BAD_PARAMETER;

- wmi_parse_guid(guid, tmp);
- wmi_swap_bytes(tmp, guid_input);
+ if (uuid_le_to_bin(guid, &guid_input))
+ return AE_BAD_PARAMETER;

list_for_each(p, &wmi_block_list) {
acpi_status wmi_status;
block = list_entry(p, struct wmi_block, list);

- if (memcmp(block->gblock.guid, guid_input, 16) == 0) {
+ if (memcmp(block->gblock.guid, &guid_input, 16) == 0) {
if (!block->handler ||
block->handler == wmi_notify_debug)
return AE_NULL_ENTRY;
--
2.8.0.rc3