/* Copyright (c) 2017, The Linux Foundation. All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 and
 * only version 2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */

#include <drm/drm_edid.h>

#include "sde_kms.h"
#include "sde_edid_parser.h"

#define DBC_START_OFFSET 4
#define EDID_DTD_LEN 18

enum data_block_types {
	RESERVED,
	AUDIO_DATA_BLOCK,
	VIDEO_DATA_BLOCK,
	VENDOR_SPECIFIC_DATA_BLOCK,
	SPEAKER_ALLOCATION_DATA_BLOCK,
	VESA_DTC_DATA_BLOCK,
	RESERVED2,
	USE_EXTENDED_TAG
};

static u8 *sde_find_edid_extension(struct edid *edid, int ext_id)
{
	u8 *edid_ext = NULL;
	int i;

	/* No EDID or EDID extensions */
	if (edid == NULL || edid->extensions == 0)
		return NULL;

	/* Find CEA extension */
	for (i = 0; i < edid->extensions; i++) {
		edid_ext = (u8 *)edid + EDID_LENGTH * (i + 1);
		if (edid_ext[0] == ext_id)
			break;
	}

	if (i == edid->extensions)
		return NULL;

	return edid_ext;
}

static u8 *sde_find_cea_extension(struct edid *edid)
{
	return sde_find_edid_extension(edid, SDE_CEA_EXT);
}

static int
sde_cea_db_payload_len(const u8 *db)
{
	return db[0] & 0x1f;
}

static int
sde_cea_db_tag(const u8 *db)
{
	return db[0] >> 5;
}

static int
sde_cea_revision(const u8 *cea)
{
	return cea[1];
}

static int
sde_cea_db_offsets(const u8 *cea, int *start, int *end)
{
	/* Data block offset in CEA extension block */
	*start = 4;
	*end = cea[2];
	if (*end == 0)
		*end = 127;
	if (*end < 4 || *end > 127)
		return -ERANGE;
	return 0;
}

#define sde_for_each_cea_db(cea, i, start, end) \
for ((i) = (start); \
(i) < (end) && (i) + sde_cea_db_payload_len(&(cea)[(i)]) < (end); \
(i) += sde_cea_db_payload_len(&(cea)[(i)]) + 1)

static bool sde_cea_db_is_hdmi_hf_vsdb(const u8 *db)
{
	int hdmi_id;

	if (sde_cea_db_tag(db) != VENDOR_SPECIFIC_DATA_BLOCK)
		return false;

	if (sde_cea_db_payload_len(db) < 7)
		return false;

	hdmi_id = db[1] | (db[2] << 8) | (db[3] << 16);

	return hdmi_id == HDMI_IEEE_OUI_HF;
}

static u8 *sde_edid_find_extended_tag_block(struct edid *edid, int blk_id)
{
	u8 *db = NULL;
	u8 *cea = NULL;

	if (!edid) {
		SDE_ERROR("%s: invalid input\n", __func__);
		return NULL;
	}

	cea = sde_find_cea_extension(edid);

	if (cea && sde_cea_revision(cea) >= 3) {
		int i, start, end;

		if (sde_cea_db_offsets(cea, &start, &end))
			return NULL;

		sde_for_each_cea_db(cea, i, start, end) {
			db = &cea[i];
			if ((sde_cea_db_tag(db) == SDE_EXTENDED_TAG) &&
				(db[1] == blk_id))
				return db;
		}
	}
	return NULL;
}

static u8 *
sde_edid_find_block(struct edid *edid, int blk_id)
{
	u8 *db = NULL;
	u8 *cea = NULL;

	if (!edid) {
		SDE_ERROR("%s: invalid input\n", __func__);
		return NULL;
	}

	cea = sde_find_cea_extension(edid);

	if (cea && sde_cea_revision(cea) >= 3) {
		int i, start, end;

		if (sde_cea_db_offsets(cea, &start, &end))
			return NULL;

		sde_for_each_cea_db(cea, i, start, end) {
			db = &cea[i];
			if (sde_cea_db_tag(db) == blk_id)
				return db;
		}
	}
	return NULL;
}


static const u8 *_sde_edid_find_block(const u8 *in_buf, u32 start_offset,
	u8 type, u8 *len)
{
	/* the start of data block collection, start of Video Data Block */
	u32 offset = start_offset;
	u32 dbc_offset = in_buf[2];

	SDE_EDID_DEBUG("%s +", __func__);
	/*
	 * * edid buffer 1, byte 2 being 4 means no non-DTD/Data block
	 *   collection present.
	 * * edid buffer 1, byte 2 being 0 means no non-DTD/DATA block
	 *   collection present and no DTD data present.
	 */
	if ((dbc_offset == 0) || (dbc_offset == 4)) {
		SDE_ERROR("EDID: no DTD or non-DTD data present\n");
		return NULL;
	}

	while (offset < dbc_offset) {
		u8 block_len = in_buf[offset] & 0x1F;

		if ((offset + block_len <= dbc_offset) &&
		    (in_buf[offset] >> 5) == type) {
			*len = block_len;
			SDE_EDID_DEBUG("block=%d found @ 0x%x w/ len=%d\n",
				type, offset, block_len);

			return in_buf + offset;
		}
		offset += 1 + block_len;
	}

	return NULL;
}

static void sde_edid_extract_vendor_id(struct sde_edid_ctrl *edid_ctrl)
{
	char *vendor_id;
	u32 id_codes;

	SDE_EDID_DEBUG("%s +", __func__);
	if (!edid_ctrl) {
		SDE_ERROR("%s: invalid input\n", __func__);
		return;
	}

	vendor_id = edid_ctrl->vendor_id;
	id_codes = ((u32)edid_ctrl->edid->mfg_id[0] << 8) +
		edid_ctrl->edid->mfg_id[1];

	vendor_id[0] = 'A' - 1 + ((id_codes >> 10) & 0x1F);
	vendor_id[1] = 'A' - 1 + ((id_codes >> 5) & 0x1F);
	vendor_id[2] = 'A' - 1 + (id_codes & 0x1F);
	vendor_id[3] = 0;
	SDE_EDID_DEBUG("vendor id is %s ", vendor_id);
	SDE_EDID_DEBUG("%s -", __func__);
}

static void sde_edid_set_y420_support(struct drm_connector *connector,
u32 video_format)
{
	u8 cea_mode = 0;
	struct drm_display_mode *mode;
	u32 mode_fmt_flags = 0;

	/* Need to add Y420 support flag to the modes */
	list_for_each_entry(mode, &connector->probed_modes, head) {
		/* Cache the format flags before clearing */
		mode_fmt_flags = mode->flags;
		/* Clear the RGB/YUV format flags before calling upstream API */
		mode->flags &= ~SDE_DRM_MODE_FLAG_FMT_MASK;
		cea_mode = drm_match_cea_mode(mode);
		/* Restore the format flags */
		mode->flags = mode_fmt_flags;
		if ((cea_mode != 0) && (cea_mode == video_format)) {
			SDE_EDID_DEBUG("%s found match for %d ", __func__,
			video_format);
			mode->flags |= DRM_MODE_FLAG_SUPPORTS_YUV;
		}
	}
}

static void sde_edid_parse_Y420CMDB(
struct drm_connector *connector, struct sde_edid_ctrl *edid_ctrl,
const u8 *db)
{
	u32 offset = 0;
	u8 cmdb_len = 0;
	u8 svd_len = 0;
	const u8 *svd = NULL;
	u32 i = 0, j = 0;
	u32 video_format = 0;

	if (!edid_ctrl) {
		SDE_ERROR("%s: edid_ctrl is NULL\n", __func__);
		return;
	}

	if (!db) {
		SDE_ERROR("%s: invalid input\n", __func__);
		return;
	}
	SDE_EDID_DEBUG("%s +\n", __func__);
	cmdb_len = db[0] & 0x1f;

	/* Byte 3 to L+1 contain SVDs */
	offset += 2;

	svd = sde_edid_find_block(edid_ctrl->edid, VIDEO_DATA_BLOCK);

	if (svd) {
		/*moving to the next byte as vic info begins there*/
		svd_len = svd[0] & 0x1f;
		++svd;
	}

	for (i = 0; i < svd_len; i++, j++) {
		video_format = *(svd + i) & 0x7F;
		if (cmdb_len == 1) {
			/* If cmdb_len is 1, it means all SVDs support YUV */
			sde_edid_set_y420_support(connector, video_format);
		} else if (db[offset] & (1 << j)) {
			sde_edid_set_y420_support(connector, video_format);

			if (j & 0x80) {
				j = j/8;
				offset++;
				if (offset >= cmdb_len)
					break;
			}
		}
	}

	SDE_EDID_DEBUG("%s -\n", __func__);

}

static void sde_edid_parse_Y420VDB(
struct drm_connector *connector, struct sde_edid_ctrl *edid_ctrl,
const u8 *db)
{
	u8 len = db[0] & 0x1f;
	u32 i = 0;
	u32 video_format = 0;

	if (!edid_ctrl) {
		SDE_ERROR("%s: invalid input\n", __func__);
		return;
	}

	SDE_EDID_DEBUG("%s +\n", __func__);

	/* Offset to byte 3 */
	db += 2;
	for (i = 0; i < len - 1; i++) {
		video_format = *(db + i) & 0x7F;
		/*
		 * mode was already added in get_modes()
		 * only need to set the Y420 support flag
		 */
		sde_edid_set_y420_support(connector, video_format);
	}
	SDE_EDID_DEBUG("%s -", __func__);
}

static void sde_edid_set_mode_format(
struct drm_connector *connector, struct sde_edid_ctrl *edid_ctrl)
{
	const u8 *db = NULL;
	struct drm_display_mode *mode;

	SDE_EDID_DEBUG("%s +\n", __func__);
	/* Set YUV mode support flags for YCbcr420VDB */
	db = sde_edid_find_extended_tag_block(edid_ctrl->edid,
			Y420_VIDEO_DATA_BLOCK);
	if (db)
		sde_edid_parse_Y420VDB(connector, edid_ctrl, db);
	else
		SDE_EDID_DEBUG("YCbCr420 VDB is not present\n");

	/* Set RGB supported on all modes where YUV is not set */
	list_for_each_entry(mode, &connector->probed_modes, head) {
		if (!(mode->flags & DRM_MODE_FLAG_SUPPORTS_YUV))
			mode->flags |= DRM_MODE_FLAG_SUPPORTS_RGB;
	}


	db = sde_edid_find_extended_tag_block(edid_ctrl->edid,
			Y420_CAPABILITY_MAP_DATA_BLOCK);
	if (db)
		sde_edid_parse_Y420CMDB(connector, edid_ctrl, db);
	else
		SDE_EDID_DEBUG("YCbCr420 CMDB is not present\n");

	SDE_EDID_DEBUG("%s -\n", __func__);
}

static void _sde_edid_update_dc_modes(
struct drm_connector *connector, struct sde_edid_ctrl *edid_ctrl)
{
	int i, start, end;
	u8 *edid_ext, *hdmi;
	struct drm_display_info *disp_info;
	u32 hdmi_dc_yuv_modes = 0;

	SDE_EDID_DEBUG("%s +\n", __func__);

	if (!connector || !edid_ctrl) {
		SDE_ERROR("invalid input\n");
		return;
	}

	disp_info = &connector->display_info;

	edid_ext = sde_find_cea_extension(edid_ctrl->edid);

	if (!edid_ext) {
		SDE_ERROR("no cea extension\n");
		return;
	}

	if (sde_cea_db_offsets(edid_ext, &start, &end))
		return;

	sde_for_each_cea_db(edid_ext, i, start, end) {
		if (sde_cea_db_is_hdmi_hf_vsdb(&edid_ext[i])) {

			hdmi = &edid_ext[i];

			if (sde_cea_db_payload_len(hdmi) < 7)
				continue;

			if (hdmi[7] & DRM_EDID_YCBCR420_DC_30) {
				hdmi_dc_yuv_modes |= DRM_EDID_YCBCR420_DC_30;
				SDE_EDID_DEBUG("Y420 30-bit supported\n");
			}

			if (hdmi[7] & DRM_EDID_YCBCR420_DC_36) {
				hdmi_dc_yuv_modes |= DRM_EDID_YCBCR420_DC_36;
				SDE_EDID_DEBUG("Y420 36-bit supported\n");
			}

			if (hdmi[7] & DRM_EDID_YCBCR420_DC_48) {
				hdmi_dc_yuv_modes |= DRM_EDID_YCBCR420_DC_36;
				SDE_EDID_DEBUG("Y420 48-bit supported\n");
			}
		}
	}

	disp_info->edid_hdmi_dc_modes |= hdmi_dc_yuv_modes;

	SDE_EDID_DEBUG("%s -\n", __func__);
}

static void _sde_edid_extract_audio_data_blocks(
	struct sde_edid_ctrl *edid_ctrl)
{
	u8 len = 0;
	u8 adb_max = 0;
	const u8 *adb = NULL;
	u32 offset = DBC_START_OFFSET;
	u8 *cea = NULL;

	if (!edid_ctrl) {
		SDE_ERROR("invalid edid_ctrl\n");
		return;
	}
	SDE_EDID_DEBUG("%s +", __func__);
	cea = sde_find_cea_extension(edid_ctrl->edid);
	if (!cea) {
		SDE_DEBUG("CEA extension not found\n");
		return;
	}

	edid_ctrl->adb_size = 0;

	memset(edid_ctrl->audio_data_block, 0,
		sizeof(edid_ctrl->audio_data_block));

	do {
		len = 0;
		adb = _sde_edid_find_block(cea, offset, AUDIO_DATA_BLOCK,
			&len);

		if ((adb == NULL) || (len > MAX_AUDIO_DATA_BLOCK_SIZE ||
			adb_max >= MAX_NUMBER_ADB)) {
			if (!edid_ctrl->adb_size) {
				SDE_DEBUG("No/Invalid Audio Data Block\n");
				return;
			}

			continue;
		}

		memcpy(edid_ctrl->audio_data_block + edid_ctrl->adb_size,
			adb + 1, len);
		offset = (adb - cea) + 1 + len;

		edid_ctrl->adb_size += len;
		adb_max++;
	} while (adb);
	SDE_EDID_DEBUG("%s -", __func__);
}

static void _sde_edid_extract_speaker_allocation_data(
	struct sde_edid_ctrl *edid_ctrl)
{
	u8 len;
	const u8 *sadb = NULL;
	u8 *cea = NULL;

	if (!edid_ctrl) {
		SDE_ERROR("invalid edid_ctrl\n");
		return;
	}
	SDE_EDID_DEBUG("%s +", __func__);
	cea = sde_find_cea_extension(edid_ctrl->edid);
	if (!cea) {
		SDE_DEBUG("CEA extension not found\n");
		return;
	}

	sadb = _sde_edid_find_block(cea, DBC_START_OFFSET,
		SPEAKER_ALLOCATION_DATA_BLOCK, &len);
	if ((sadb == NULL) || (len != MAX_SPKR_ALLOC_DATA_BLOCK_SIZE)) {
		SDE_DEBUG("No/Invalid Speaker Allocation Data Block\n");
		return;
	}

	memcpy(edid_ctrl->spkr_alloc_data_block, sadb + 1, len);
	edid_ctrl->sadb_size = len;

	SDE_EDID_DEBUG("speaker alloc data SP byte = %08x %s%s%s%s%s%s%s\n",
		sadb[1],
		(sadb[1] & BIT(0)) ? "FL/FR," : "",
		(sadb[1] & BIT(1)) ? "LFE," : "",
		(sadb[1] & BIT(2)) ? "FC," : "",
		(sadb[1] & BIT(3)) ? "RL/RR," : "",
		(sadb[1] & BIT(4)) ? "RC," : "",
		(sadb[1] & BIT(5)) ? "FLC/FRC," : "",
		(sadb[1] & BIT(6)) ? "RLC/RRC," : "");
	SDE_EDID_DEBUG("%s -", __func__);
}

struct sde_edid_ctrl *sde_edid_init(void)
{
	struct sde_edid_ctrl *edid_ctrl = NULL;

	SDE_EDID_DEBUG("%s +\n", __func__);
	edid_ctrl = kzalloc(sizeof(*edid_ctrl), GFP_KERNEL);
	if (!edid_ctrl) {
		SDE_ERROR("edid_ctrl alloc failed\n");
		return NULL;
	}
	memset((edid_ctrl), 0, sizeof(*edid_ctrl));
	SDE_EDID_DEBUG("%s -\n", __func__);
	return edid_ctrl;
}

void sde_free_edid(void **input)
{
	struct sde_edid_ctrl *edid_ctrl = (struct sde_edid_ctrl *)(*input);

	SDE_EDID_DEBUG("%s +", __func__);
	kfree(edid_ctrl->edid);
	edid_ctrl->edid = NULL;
}

void sde_edid_deinit(void **input)
{
	struct sde_edid_ctrl *edid_ctrl = (struct sde_edid_ctrl *)(*input);

	SDE_EDID_DEBUG("%s +", __func__);
	sde_free_edid((void *)&edid_ctrl);
	kfree(edid_ctrl);
	SDE_EDID_DEBUG("%s -", __func__);
}

int _sde_edid_update_modes(struct drm_connector *connector,
	void *input)
{
	int rc = 0;
	struct sde_edid_ctrl *edid_ctrl = (struct sde_edid_ctrl *)(input);

	SDE_EDID_DEBUG("%s +", __func__);
	if (edid_ctrl->edid) {
		drm_mode_connector_update_edid_property(connector,
			edid_ctrl->edid);

		rc = drm_add_edid_modes(connector, edid_ctrl->edid);
		sde_edid_set_mode_format(connector, edid_ctrl);
		_sde_edid_update_dc_modes(connector, edid_ctrl);
		SDE_EDID_DEBUG("%s -", __func__);
		return rc;
	}

	drm_mode_connector_update_edid_property(connector, NULL);
	SDE_EDID_DEBUG("%s null edid -", __func__);
	return rc;
}

u32 sde_get_sink_bpc(void *input)
{
	struct sde_edid_ctrl *edid_ctrl = (struct sde_edid_ctrl *)(input);
	struct edid *edid = edid_ctrl->edid;

	if (!edid) {
		SDE_ERROR("invalid edid input\n");
		return 0;
	}

	if ((edid->revision < 3) || !(edid->input & DRM_EDID_INPUT_DIGITAL))
		return 0;

	if (edid->revision < 4) {
		if (edid->input & DRM_EDID_DIGITAL_TYPE_DVI)
			return 8;
		else
			return 0;
	}

	switch (edid->input & DRM_EDID_DIGITAL_DEPTH_MASK) {
	case DRM_EDID_DIGITAL_DEPTH_6:
		return 6;
	case DRM_EDID_DIGITAL_DEPTH_8:
		return 8;
	case DRM_EDID_DIGITAL_DEPTH_10:
		return 10;
	case DRM_EDID_DIGITAL_DEPTH_12:
		return 12;
	case DRM_EDID_DIGITAL_DEPTH_14:
		return 14;
	case DRM_EDID_DIGITAL_DEPTH_16:
		return 16;
	case DRM_EDID_DIGITAL_DEPTH_UNDEF:
	default:
		return 0;
	}
}

u8 sde_get_edid_checksum(void *input)
{
	struct sde_edid_ctrl *edid_ctrl = (struct sde_edid_ctrl *)(input);
	struct edid *edid = NULL, *last_block = NULL;
	u8 *raw_edid = NULL;

	if (!edid_ctrl || !edid_ctrl->edid) {
		SDE_ERROR("invalid edid input\n");
		return 0;
	}

	edid = edid_ctrl->edid;

	raw_edid = (u8 *)edid;
	raw_edid += (edid->extensions * EDID_LENGTH);
	last_block = (struct edid *)raw_edid;

	if (last_block)
		return last_block->checksum;

	SDE_ERROR("Invalid block, no checksum\n");
	return 0;
}

bool sde_detect_hdmi_monitor(void *input)
{
	struct sde_edid_ctrl *edid_ctrl = (struct sde_edid_ctrl *)(input);

	return drm_detect_hdmi_monitor(edid_ctrl->edid);
}

void sde_get_edid(struct drm_connector *connector,
				  struct i2c_adapter *adapter, void **input)
{
	struct sde_edid_ctrl *edid_ctrl = (struct sde_edid_ctrl *)(*input);

	edid_ctrl->edid = drm_get_edid(connector, adapter);
	SDE_EDID_DEBUG("%s +\n", __func__);

	if (!edid_ctrl->edid)
		SDE_ERROR("EDID read failed\n");

	if (edid_ctrl->edid) {
		sde_edid_extract_vendor_id(edid_ctrl);
		_sde_edid_extract_audio_data_blocks(edid_ctrl);
		_sde_edid_extract_speaker_allocation_data(edid_ctrl);
	}
	SDE_EDID_DEBUG("%s -\n", __func__);
};