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media: cec: make cec_get_edid_spa_location() an inline function

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[ Upstream commit b915bf575d ]

This function is needed by both V4L2 and CEC, so move this to
cec.h as a static inline since there are no obvious shared
modules between the two subsystems.

This patch, together with the following ones, fixes a
dependency bug: if CEC_CORE is disabled, then building adv7604
(and other HDMI receivers) will fail because an essential
function is now stubbed out.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Cc: <stable@vger.kernel.org>      # for v4.17 and up
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
This commit is contained in:
Hans Verkuil 2018-09-13 03:25:59 -04:00 committed by Greg Kroah-Hartman
parent 363b93186f
commit c93155fed0
2 changed files with 70 additions and 60 deletions
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60
drivers/media/cec/cec-edid.c
View File

@ -22,66 +22,6 @@
#include <linux/types.h>
#include <media/cec.h>
/*
* This EDID is expected to be a CEA-861 compliant, which means that there are
* at least two blocks and one or more of the extensions blocks are CEA-861
* blocks.
*
* The returned location is guaranteed to be < size - 1.
*/
static unsigned int cec_get_edid_spa_location(const u8 *edid, unsigned int size)
{
unsigned int blocks = size / 128;
unsigned int block;
u8 d;
/* Sanity check: at least 2 blocks and a multiple of the block size */
if (blocks < 2 || size % 128)
return 0;
/*
* If there are fewer extension blocks than the size, then update
* 'blocks'. It is allowed to have more extension blocks than the size,
* since some hardware can only read e.g. 256 bytes of the EDID, even
* though more blocks are present. The first CEA-861 extension block
* should normally be in block 1 anyway.
*/
if (edid[0x7e] + 1 < blocks)
blocks = edid[0x7e] + 1;
for (block = 1; block < blocks; block++) {
unsigned int offset = block * 128;
/* Skip any non-CEA-861 extension blocks */
if (edid[offset] != 0x02 || edid[offset + 1] != 0x03)
continue;
/* search Vendor Specific Data Block (tag 3) */
d = edid[offset + 2] & 0x7f;
/* Check if there are Data Blocks */
if (d <= 4)
continue;
if (d > 4) {
unsigned int i = offset + 4;
unsigned int end = offset + d;
/* Note: 'end' is always < 'size' */
do {
u8 tag = edid[i] >> 5;
u8 len = edid[i] & 0x1f;
if (tag == 3 && len >= 5 && i + len <= end &&
edid[i + 1] == 0x03 &&
edid[i + 2] == 0x0c &&
edid[i + 3] == 0x00)
return i + 4;
i += len + 1;
} while (i < end);
}
}
return 0;
}
u16 cec_get_edid_phys_addr(const u8 *edid, unsigned int size,
unsigned int *offset)
{

70
include/media/cec.h
View File

@ -435,4 +435,74 @@ static inline void cec_phys_addr_invalidate(struct cec_adapter *adap)
cec_s_phys_addr(adap, CEC_PHYS_ADDR_INVALID, false);
}
/**
* cec_get_edid_spa_location() - find location of the Source Physical Address
*
* @edid: the EDID
* @size: the size of the EDID
*
* This EDID is expected to be a CEA-861 compliant, which means that there are
* at least two blocks and one or more of the extensions blocks are CEA-861
* blocks.
*
* The returned location is guaranteed to be <= size-2.
*
* This is an inline function since it is used by both CEC and V4L2.
* Ideally this would go in a module shared by both, but it is overkill to do
* that for just a single function.
*/
static inline unsigned int cec_get_edid_spa_location(const u8 *edid,
unsigned int size)
{
unsigned int blocks = size / 128;
unsigned int block;
u8 d;
/* Sanity check: at least 2 blocks and a multiple of the block size */
if (blocks < 2 || size % 128)
return 0;
/*
* If there are fewer extension blocks than the size, then update
* 'blocks'. It is allowed to have more extension blocks than the size,
* since some hardware can only read e.g. 256 bytes of the EDID, even
* though more blocks are present. The first CEA-861 extension block
* should normally be in block 1 anyway.
*/
if (edid[0x7e] + 1 < blocks)
blocks = edid[0x7e] + 1;
for (block = 1; block < blocks; block++) {
unsigned int offset = block * 128;
/* Skip any non-CEA-861 extension blocks */
if (edid[offset] != 0x02 || edid[offset + 1] != 0x03)
continue;
/* search Vendor Specific Data Block (tag 3) */
d = edid[offset + 2] & 0x7f;
/* Check if there are Data Blocks */
if (d <= 4)
continue;
if (d > 4) {
unsigned int i = offset + 4;
unsigned int end = offset + d;
/* Note: 'end' is always < 'size' */
do {
u8 tag = edid[i] >> 5;
u8 len = edid[i] & 0x1f;
if (tag == 3 && len >= 5 && i + len <= end &&
edid[i + 1] == 0x03 &&
edid[i + 2] == 0x0c &&
edid[i + 3] == 0x00)
return i + 4;
i += len + 1;
} while (i < end);
}
}
return 0;
}
#endif /* _MEDIA_CEC_H */