Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
drm/eld: add helpers to modify the SADs of an ELD
Occasionally it's necessary for drivers to modify the SADs of an ELD,
but it's not so cool to have drivers poke at the ELD buffer directly.
Using the helpers to translate between 3-byte SAD and struct cea_sad,
add ELD helpers to get/set the SADs from/to an ELD.
v2: s/i/sad_index/ (Mitul)
Cc: Mitul Golani <mitulkumar.ajitkumar.golani@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Mitul Golani <mitulkumar.ajitkumar.golani@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/8e9a05f2b1e0dd184132d636e1e778e8917ec25d.1698747331.git.jani.nikula@intel.com
+64
+3
Documentation/gpu/drm-kms-helpers.rst
+3
Documentation/gpu/drm-kms-helpers.rst
+1
drivers/gpu/drm/Makefile
+1
drivers/gpu/drm/Makefile
+55
drivers/gpu/drm/drm_eld.c
+55
drivers/gpu/drm/drm_eld.c
···
1
+
// SPDX-License-Identifier: MIT
2
+
/*
3
+
* Copyright © 2023 Intel Corporation
4
+
*/
5
+
6
+
#include <drm/drm_edid.h>
7
+
#include <drm/drm_eld.h>
8
+
9
+
#include "drm_internal.h"
10
+
11
+
/**
12
+
* drm_eld_sad_get - get SAD from ELD to struct cea_sad
13
+
* @eld: ELD buffer
14
+
* @sad_index: SAD index
15
+
* @cta_sad: destination struct cea_sad
16
+
*
17
+
* @return: 0 on success, or negative on errors
18
+
*/
19
+
int drm_eld_sad_get(const u8 *eld, int sad_index, struct cea_sad *cta_sad)
20
+
{
21
+
const u8 *sad;
22
+
23
+
if (sad_index >= drm_eld_sad_count(eld))
24
+
return -EINVAL;
25
+
26
+
sad = eld + DRM_ELD_CEA_SAD(drm_eld_mnl(eld), sad_index);
27
+
28
+
drm_edid_cta_sad_set(cta_sad, sad);
29
+
30
+
return 0;
31
+
}
32
+
EXPORT_SYMBOL(drm_eld_sad_get);
33
+
34
+
/**
35
+
* drm_eld_sad_set - set SAD to ELD from struct cea_sad
36
+
* @eld: ELD buffer
37
+
* @sad_index: SAD index
38
+
* @cta_sad: source struct cea_sad
39
+
*
40
+
* @return: 0 on success, or negative on errors
41
+
*/
42
+
int drm_eld_sad_set(u8 *eld, int sad_index, const struct cea_sad *cta_sad)
43
+
{
44
+
u8 *sad;
45
+
46
+
if (sad_index >= drm_eld_sad_count(eld))
47
+
return -EINVAL;
48
+
49
+
sad = eld + DRM_ELD_CEA_SAD(drm_eld_mnl(eld), sad_index);
50
+
51
+
drm_edid_cta_sad_get(cta_sad, sad);
52
+
53
+
return 0;
54
+
}
55
+
EXPORT_SYMBOL(drm_eld_sad_set);
+5
include/drm/drm_eld.h
+5
include/drm/drm_eld.h
···
8
8
9
9
#include <linux/types.h>
10
10
11
+
struct cea_sad;
12
+
11
13
/* ELD Header Block */
12
14
#define DRM_ELD_HEADER_BLOCK_SIZE 4
13
15
···
76
74
{
77
75
return (eld[DRM_ELD_CEA_EDID_VER_MNL] & DRM_ELD_MNL_MASK) >> DRM_ELD_MNL_SHIFT;
78
76
}
77
+
78
+
int drm_eld_sad_get(const u8 *eld, int sad_index, struct cea_sad *cta_sad);
79
+
int drm_eld_sad_set(u8 *eld, int sad_index, const struct cea_sad *cta_sad);
79
80
80
81
/**
81
82
* drm_eld_sad - Get ELD SAD structures.