Commit b915bf57 authored by Hans Verkuil's avatar Hans Verkuil Committed by Mauro Carvalho Chehab
Browse files

media: cec: make cec_get_edid_spa_location() an inline function 



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: default avatarHans Verkuil <hans.verkuil@cisco.com>
Cc: <stable@vger.kernel.org>      # for v4.17 and up
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab+samsung@kernel.org>
parent 985cdcb0

drivers/media/cec/cec-edid.c

+0 −60
Original line number Diff line number Diff line
@@ -10,66 +10,6 @@ 
#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)

{

include/media/cec.h

+70 −0
Original line number Diff line number Diff line
@@ -461,4 +461,74 @@ 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 */

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