/* SPDX-License-Identifier: MIT */
/*
* Copyright © 2023 Intel Corporation
*/
#ifndef __DRM_ELD_H__
#define __DRM_ELD_H__
#include <linux/types.h>
struct cea_sad;
/* ELD Header Block */
#define DRM_ELD_HEADER_BLOCK_SIZE 4
#define DRM_ELD_VER 0
# define DRM_ELD_VER_SHIFT 3
# define DRM_ELD_VER_MASK (0x1f << 3)
# define DRM_ELD_VER_CEA861D (2 << 3) /* supports 861D or below */
# define DRM_ELD_VER_CANNED (0x1f << 3)
#define DRM_ELD_BASELINE_ELD_LEN 2 /* in dwords! */
/* ELD Baseline Block for ELD_Ver == 2 */
#define DRM_ELD_CEA_EDID_VER_MNL 4
# define DRM_ELD_CEA_EDID_VER_SHIFT 5
# define DRM_ELD_CEA_EDID_VER_MASK (7 << 5)
# define DRM_ELD_CEA_EDID_VER_NONE (0 << 5)
# define DRM_ELD_CEA_EDID_VER_CEA861 (1 << 5)
# define DRM_ELD_CEA_EDID_VER_CEA861A (2 << 5)
# define DRM_ELD_CEA_EDID_VER_CEA861BCD (3 << 5)
# define DRM_ELD_MNL_SHIFT 0
# define DRM_ELD_MNL_MASK (0x1f << 0)
#define DRM_ELD_SAD_COUNT_CONN_TYPE 5
# define DRM_ELD_SAD_COUNT_SHIFT 4
# define DRM_ELD_SAD_COUNT_MASK (0xf << 4)
# define DRM_ELD_CONN_TYPE_SHIFT 2
# define DRM_ELD_CONN_TYPE_MASK (3 << 2)
# define DRM_ELD_CONN_TYPE_HDMI (0 << 2)
# define DRM_ELD_CONN_TYPE_DP (1 << 2)
# define DRM_ELD_SUPPORTS_AI (1 << 1)
# define DRM_ELD_SUPPORTS_HDCP (1 << 0)
#define DRM_ELD_AUD_SYNCH_DELAY 6 /* in units of 2 ms */
# define DRM_ELD_AUD_SYNCH_DELAY_MAX 0xfa /* 500 ms */
#define DRM_ELD_SPEAKER 7
# define DRM_ELD_SPEAKER_MASK 0x7f
# define DRM_ELD_SPEAKER_RLRC (1 << 6)
# define DRM_ELD_SPEAKER_FLRC (1 << 5)
# define DRM_ELD_SPEAKER_RC (1 << 4)
# define DRM_ELD_SPEAKER_RLR (1 << 3)
# define DRM_ELD_SPEAKER_FC (1 << 2)
# define DRM_ELD_SPEAKER_LFE (1 << 1)
# define DRM_ELD_SPEAKER_FLR (1 << 0)
#define DRM_ELD_PORT_ID 8 /* offsets 8..15 inclusive */
# define DRM_ELD_PORT_ID_LEN 8
#define DRM_ELD_MANUFACTURER_NAME0 16
#define DRM_ELD_MANUFACTURER_NAME1 17
#define DRM_ELD_PRODUCT_CODE0 18
#define DRM_ELD_PRODUCT_CODE1 19
#define DRM_ELD_MONITOR_NAME_STRING 20 /* offsets 20..(20+mnl-1) inclusive */
#define DRM_ELD_CEA_SAD(mnl, sad) (20 + (mnl) + 3 * (sad))
/**
* drm_eld_mnl - Get ELD monitor name length in bytes.
* @eld: pointer to an eld memory structure with mnl set
*/
static inline int drm_eld_mnl(const u8 *eld)
{
return (eld[DRM_ELD_CEA_EDID_VER_MNL] & DRM_ELD_MNL_MASK) >> DRM_ELD_MNL_SHIFT;
}
int drm_eld_sad_get(const u8 *eld, int sad_index, struct cea_sad *cta_sad);
int drm_eld_sad_set(u8 *eld, int sad_index, const struct cea_sad *cta_sad);
/**
* drm_eld_sad - Get ELD SAD structures.
* @eld: pointer to an eld memory structure with sad_count set
*/
static inline const u8 *drm_eld_sad(const u8 *eld)
{
unsigned int ver, mnl;
ver = (eld[DRM_ELD_VER] & DRM_ELD_VER_MASK) >> DRM_ELD_VER_SHIFT;
if (ver != 2 && ver != 31)
return NULL;
mnl = drm_eld_mnl(eld);
if (mnl > 16)
return NULL;
return eld + DRM_ELD_CEA_SAD(mnl, 0);
}
/**
* drm_eld_sad_count - Get ELD SAD count.
* @eld: pointer to an eld memory structure with sad_count set
*/
static inline int drm_eld_sad_count(const u8 *eld)
{
return (eld[DRM_ELD_SAD_COUNT_CONN_TYPE] & DRM_ELD_SAD_COUNT_MASK) >>
DRM_ELD_SAD_COUNT_SHIFT;
}
/**
* drm_eld_calc_baseline_block_size - Calculate baseline block size in bytes
* @eld: pointer to an eld memory structure with mnl and sad_count set
*
* This is a helper for determining the payload size of the baseline block, in
* bytes, for e.g. setting the Baseline_ELD_Len field in the ELD header block.
*/
static inline int drm_eld_calc_baseline_block_size(const u8 *eld)
{
return DRM_ELD_MONITOR_NAME_STRING - DRM_ELD_HEADER_BLOCK_SIZE +
drm_eld_mnl(eld) + drm_eld_sad_count(eld) * 3;
}
/**
* drm_eld_size - Get ELD size in bytes
* @eld: pointer to a complete eld memory structure
*
* The returned value does not include the vendor block. It's vendor specific,
* and comprises of the remaining bytes in the ELD memory buffer after
* drm_eld_size() bytes of header and baseline block.
*
* The returned value is guaranteed to be a multiple of 4.
*/
static inline int drm_eld_size(const u8 *eld)
{
return DRM_ELD_HEADER_BLOCK_SIZE + eld[DRM_ELD_BASELINE_ELD_LEN] * 4;
}
/**
* drm_eld_get_spk_alloc - Get speaker allocation
* @eld: pointer to an ELD memory structure
*
* The returned value is the speakers mask. User has to use %DRM_ELD_SPEAKER
* field definitions to identify speakers.
*/
static inline u8 drm_eld_get_spk_alloc(const u8 *eld)
{
return eld[DRM_ELD_SPEAKER] & DRM_ELD_SPEAKER_MASK;
}
/**
* drm_eld_get_conn_type - Get device type hdmi/dp connected
* @eld: pointer to an ELD memory structure
*
* The caller need to use %DRM_ELD_CONN_TYPE_HDMI or %DRM_ELD_CONN_TYPE_DP to
* identify the display type connected.
*/
static inline u8 drm_eld_get_conn_type(const u8 *eld)
{
return eld[DRM_ELD_SAD_COUNT_CONN_TYPE] & DRM_ELD_CONN_TYPE_MASK;
}
#endif /* __DRM_ELD_H__ */