drm: bridge: analogix/dp: split exynos dp driver to bridge directory

Split the dp core driver from exynos directory to bridge directory,
and rename the core driver to analogix_dp_*, rename the platform
code to exynos_dp.

Beside the new analogix_dp driver would export six hooks.
"analogix_dp_bind()" and "analogix_dp_unbind()"
"analogix_dp_suspned()" and "analogix_dp_resume()"
"analogix_dp_detect()" and "analogix_dp_get_modes()"

The bind/unbind symbols is used for analogix platform driver to connect
with analogix_dp core driver. And the detect/get_modes is used for analogix
platform driver to init the connector.

They reason why connector need register in helper driver is rockchip drm
haven't implement the atomic API, but Exynos drm have implement it, so
there would need two different connector helper functions, that's why we
leave the connector register in helper driver.

Acked-by: Inki Dae <inki.dae@samsung.com>
Tested-by: Caesar Wang <wxt@rock-chips.com>
Tested-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Yakir Yang <ykk@rock-chips.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>

1 files changed, 1351 insertions, 0 deletions

diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
new file mode 100644
index 000000000000..392c29691d34
--- /dev/null
+++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
@@ -0,0 +1,1351 @@
+/*
+* Analogix DP (Display Port) core interface driver.
+*
+* Copyright (C) 2012 Samsung Electronics Co., Ltd.
+* Author: Jingoo Han <jg1.han@samsung.com>
+*
+* This program is free software; you can redistribute it and/or modify it
+* under the terms of the GNU General Public License as published by the
+* Free Software Foundation; either version 2 of the License, or (at your
+* option) any later version.
+*/
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/interrupt.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
+#include <linux/gpio.h>
+#include <linux/component.h>
+#include <linux/phy/phy.h>
+
+#include <drm/drmP.h>
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_crtc.h>
+#include <drm/drm_crtc_helper.h>
+#include <drm/drm_panel.h>
+
+#include <drm/bridge/analogix_dp.h>
+
+#include "analogix_dp_core.h"
+
+#define to_dp(nm)	container_of(nm, struct analogix_dp_device, nm)
+
+struct bridge_init {
+	struct i2c_client *client;
+	struct device_node *node;
+};
+
+static void analogix_dp_init_dp(struct analogix_dp_device *dp)
+{
+	analogix_dp_reset(dp);
+
+	analogix_dp_swreset(dp);
+
+	analogix_dp_init_analog_param(dp);
+	analogix_dp_init_interrupt(dp);
+
+	/* SW defined function Normal operation */
+	analogix_dp_enable_sw_function(dp);
+
+	analogix_dp_config_interrupt(dp);
+	analogix_dp_init_analog_func(dp);
+
+	analogix_dp_init_hpd(dp);
+	analogix_dp_init_aux(dp);
+}
+
+static int analogix_dp_detect_hpd(struct analogix_dp_device *dp)
+{
+	int timeout_loop = 0;
+
+	while (analogix_dp_get_plug_in_status(dp) != 0) {
+		timeout_loop++;
+		if (DP_TIMEOUT_LOOP_COUNT < timeout_loop) {
+			dev_err(dp->dev, "failed to get hpd plug status\n");
+			return -ETIMEDOUT;
+		}
+		usleep_range(10, 11);
+	}
+
+	return 0;
+}
+
+static unsigned char analogix_dp_calc_edid_check_sum(unsigned char *edid_data)
+{
+	int i;
+	unsigned char sum = 0;
+
+	for (i = 0; i < EDID_BLOCK_LENGTH; i++)
+		sum = sum + edid_data[i];
+
+	return sum;
+}
+
+static int analogix_dp_read_edid(struct analogix_dp_device *dp)
+{
+	unsigned char edid[EDID_BLOCK_LENGTH * 2];
+	unsigned int extend_block = 0;
+	unsigned char sum;
+	unsigned char test_vector;
+	int retval;
+
+	/*
+	 * EDID device address is 0x50.
+	 * However, if necessary, you must have set upper address
+	 * into E-EDID in I2C device, 0x30.
+	 */
+
+	/* Read Extension Flag, Number of 128-byte EDID extension blocks */
+	retval = analogix_dp_read_byte_from_i2c(dp, I2C_EDID_DEVICE_ADDR,
+				EDID_EXTENSION_FLAG,
+				&extend_block);
+	if (retval)
+		return retval;
+
+	if (extend_block > 0) {
+		dev_dbg(dp->dev, "EDID data includes a single extension!\n");
+
+		/* Read EDID data */
+		retval = analogix_dp_read_bytes_from_i2c(dp, I2C_EDID_DEVICE_ADDR,
+						EDID_HEADER_PATTERN,
+						EDID_BLOCK_LENGTH,
+						&edid[EDID_HEADER_PATTERN]);
+		if (retval != 0) {
+			dev_err(dp->dev, "EDID Read failed!\n");
+			return -EIO;
+		}
+		sum = analogix_dp_calc_edid_check_sum(edid);
+		if (sum != 0) {
+			dev_err(dp->dev, "EDID bad checksum!\n");
+			return -EIO;
+		}
+
+		/* Read additional EDID data */
+		retval = analogix_dp_read_bytes_from_i2c(dp,
+				I2C_EDID_DEVICE_ADDR,
+				EDID_BLOCK_LENGTH,
+				EDID_BLOCK_LENGTH,
+				&edid[EDID_BLOCK_LENGTH]);
+		if (retval != 0) {
+			dev_err(dp->dev, "EDID Read failed!\n");
+			return -EIO;
+		}
+		sum = analogix_dp_calc_edid_check_sum(&edid[EDID_BLOCK_LENGTH]);
+		if (sum != 0) {
+			dev_err(dp->dev, "EDID bad checksum!\n");
+			return -EIO;
+		}
+
+		analogix_dp_read_byte_from_dpcd(dp, DP_TEST_REQUEST,
+					&test_vector);
+		if (test_vector & DP_TEST_LINK_EDID_READ) {
+			analogix_dp_write_byte_to_dpcd(dp,
+				DP_TEST_EDID_CHECKSUM,
+				edid[EDID_BLOCK_LENGTH + EDID_CHECKSUM]);
+			analogix_dp_write_byte_to_dpcd(dp,
+				DP_TEST_RESPONSE,
+				DP_TEST_EDID_CHECKSUM_WRITE);
+		}
+	} else {
+		dev_info(dp->dev, "EDID data does not include any extensions.\n");
+
+		/* Read EDID data */
+		retval = analogix_dp_read_bytes_from_i2c(dp,
+				I2C_EDID_DEVICE_ADDR,
+				EDID_HEADER_PATTERN,
+				EDID_BLOCK_LENGTH,
+				&edid[EDID_HEADER_PATTERN]);
+		if (retval != 0) {
+			dev_err(dp->dev, "EDID Read failed!\n");
+			return -EIO;
+		}
+		sum = analogix_dp_calc_edid_check_sum(edid);
+		if (sum != 0) {
+			dev_err(dp->dev, "EDID bad checksum!\n");
+			return -EIO;
+		}
+
+		analogix_dp_read_byte_from_dpcd(dp,
+			DP_TEST_REQUEST,
+			&test_vector);
+		if (test_vector & DP_TEST_LINK_EDID_READ) {
+			analogix_dp_write_byte_to_dpcd(dp,
+				DP_TEST_EDID_CHECKSUM,
+				edid[EDID_CHECKSUM]);
+			analogix_dp_write_byte_to_dpcd(dp,
+				DP_TEST_RESPONSE,
+				DP_TEST_EDID_CHECKSUM_WRITE);
+		}
+	}
+
+	dev_dbg(dp->dev, "EDID Read success!\n");
+	return 0;
+}
+
+static int analogix_dp_handle_edid(struct analogix_dp_device *dp)
+{
+	u8 buf[12];
+	int i;
+	int retval;
+
+	/* Read DPCD DP_DPCD_REV~RECEIVE_PORT1_CAP_1 */
+	retval = analogix_dp_read_bytes_from_dpcd(dp, DP_DPCD_REV,
+				12, buf);
+	if (retval)
+		return retval;
+
+	/* Read EDID */
+	for (i = 0; i < 3; i++) {
+		retval = analogix_dp_read_edid(dp);
+		if (!retval)
+			break;
+	}
+
+	return retval;
+}
+
+static void analogix_dp_enable_rx_to_enhanced_mode(struct analogix_dp_device *dp,
+						bool enable)
+{
+	u8 data;
+
+	analogix_dp_read_byte_from_dpcd(dp, DP_LANE_COUNT_SET, &data);
+
+	if (enable)
+		analogix_dp_write_byte_to_dpcd(dp, DP_LANE_COUNT_SET,
+			DP_LANE_COUNT_ENHANCED_FRAME_EN |
+			DPCD_LANE_COUNT_SET(data));
+	else
+		analogix_dp_write_byte_to_dpcd(dp, DP_LANE_COUNT_SET,
+			DPCD_LANE_COUNT_SET(data));
+}
+
+static int analogix_dp_is_enhanced_mode_available(struct analogix_dp_device *dp)
+{
+	u8 data;
+	int retval;
+
+	analogix_dp_read_byte_from_dpcd(dp, DP_MAX_LANE_COUNT, &data);
+	retval = DPCD_ENHANCED_FRAME_CAP(data);
+
+	return retval;
+}
+
+static void analogix_dp_set_enhanced_mode(struct analogix_dp_device *dp)
+{
+	u8 data;
+
+	data = analogix_dp_is_enhanced_mode_available(dp);
+	analogix_dp_enable_rx_to_enhanced_mode(dp, data);
+	analogix_dp_enable_enhanced_mode(dp, data);
+}
+
+static void analogix_dp_training_pattern_dis(struct analogix_dp_device *dp)
+{
+	analogix_dp_set_training_pattern(dp, DP_NONE);
+
+	analogix_dp_write_byte_to_dpcd(dp,
+		DP_TRAINING_PATTERN_SET,
+		DP_TRAINING_PATTERN_DISABLE);
+}
+
+static void analogix_dp_set_lane_lane_pre_emphasis(struct analogix_dp_device *dp,
+					int pre_emphasis, int lane)
+{
+	switch (lane) {
+	case 0:
+		analogix_dp_set_lane0_pre_emphasis(dp, pre_emphasis);
+		break;
+	case 1:
+		analogix_dp_set_lane1_pre_emphasis(dp, pre_emphasis);
+		break;
+
+	case 2:
+		analogix_dp_set_lane2_pre_emphasis(dp, pre_emphasis);
+		break;
+
+	case 3:
+		analogix_dp_set_lane3_pre_emphasis(dp, pre_emphasis);
+		break;
+	}
+}
+
+static int analogix_dp_link_start(struct analogix_dp_device *dp)
+{
+	u8 buf[4];
+	int lane, lane_count, pll_tries, retval;
+
+	lane_count = dp->link_train.lane_count;
+
+	dp->link_train.lt_state = CLOCK_RECOVERY;
+	dp->link_train.eq_loop = 0;
+
+	for (lane = 0; lane < lane_count; lane++)
+		dp->link_train.cr_loop[lane] = 0;
+
+	/* Set link rate and count as you want to establish*/
+	analogix_dp_set_link_bandwidth(dp, dp->link_train.link_rate);
+	analogix_dp_set_lane_count(dp, dp->link_train.lane_count);
+
+	/* Setup RX configuration */
+	buf[0] = dp->link_train.link_rate;
+	buf[1] = dp->link_train.lane_count;
+	retval = analogix_dp_write_bytes_to_dpcd(dp, DP_LINK_BW_SET,
+				2, buf);
+	if (retval)
+		return retval;
+
+	/* Set TX pre-emphasis to minimum */
+	for (lane = 0; lane < lane_count; lane++)
+		analogix_dp_set_lane_lane_pre_emphasis(dp,
+			PRE_EMPHASIS_LEVEL_0, lane);
+
+	/* Wait for PLL lock */
+	pll_tries = 0;
+	while (analogix_dp_get_pll_lock_status(dp) == PLL_UNLOCKED) {
+		if (pll_tries == DP_TIMEOUT_LOOP_COUNT) {
+			dev_err(dp->dev, "Wait for PLL lock timed out\n");
+			return -ETIMEDOUT;
+		}
+
+		pll_tries++;
+		usleep_range(90, 120);
+	}
+
+	/* Set training pattern 1 */
+	analogix_dp_set_training_pattern(dp, TRAINING_PTN1);
+
+	/* Set RX training pattern */
+	retval = analogix_dp_write_byte_to_dpcd(dp,
+			DP_TRAINING_PATTERN_SET,
+			DP_LINK_SCRAMBLING_DISABLE | DP_TRAINING_PATTERN_1);
+	if (retval)
+		return retval;
+
+	for (lane = 0; lane < lane_count; lane++)
+		buf[lane] = DP_TRAIN_PRE_EMPH_LEVEL_0 |
+			    DP_TRAIN_VOLTAGE_SWING_LEVEL_0;
+
+	retval = analogix_dp_write_bytes_to_dpcd(dp, DP_TRAINING_LANE0_SET,
+			lane_count, buf);
+
+	return retval;
+}
+
+static unsigned char analogix_dp_get_lane_status(u8 link_status[2], int lane)
+{
+	int shift = (lane & 1) * 4;
+	u8 link_value = link_status[lane>>1];
+
+	return (link_value >> shift) & 0xf;
+}
+
+static int analogix_dp_clock_recovery_ok(u8 link_status[2], int lane_count)
+{
+	int lane;
+	u8 lane_status;
+
+	for (lane = 0; lane < lane_count; lane++) {
+		lane_status = analogix_dp_get_lane_status(link_status, lane);
+		if ((lane_status & DP_LANE_CR_DONE) == 0)
+			return -EINVAL;
+	}
+	return 0;
+}
+
+static int analogix_dp_channel_eq_ok(u8 link_status[2], u8 link_align,
+				int lane_count)
+{
+	int lane;
+	u8 lane_status;
+
+	if ((link_align & DP_INTERLANE_ALIGN_DONE) == 0)
+		return -EINVAL;
+
+	for (lane = 0; lane < lane_count; lane++) {
+		lane_status = analogix_dp_get_lane_status(link_status, lane);
+		lane_status &= DP_CHANNEL_EQ_BITS;
+		if (lane_status != DP_CHANNEL_EQ_BITS)
+			return -EINVAL;
+	}
+
+	return 0;
+}
+
+static unsigned char analogix_dp_get_adjust_request_voltage(u8 adjust_request[2],
+							int lane)
+{
+	int shift = (lane & 1) * 4;
+	u8 link_value = adjust_request[lane>>1];
+
+	return (link_value >> shift) & 0x3;
+}
+
+static unsigned char analogix_dp_get_adjust_request_pre_emphasis(
+					u8 adjust_request[2],
+					int lane)
+{
+	int shift = (lane & 1) * 4;
+	u8 link_value = adjust_request[lane>>1];
+
+	return ((link_value >> shift) & 0xc) >> 2;
+}
+
+static void analogix_dp_set_lane_link_training(struct analogix_dp_device *dp,
+					u8 training_lane_set, int lane)
+{
+	switch (lane) {
+	case 0:
+		analogix_dp_set_lane0_link_training(dp, training_lane_set);
+		break;
+	case 1:
+		analogix_dp_set_lane1_link_training(dp, training_lane_set);
+		break;
+
+	case 2:
+		analogix_dp_set_lane2_link_training(dp, training_lane_set);
+		break;
+
+	case 3:
+		analogix_dp_set_lane3_link_training(dp, training_lane_set);
+		break;
+	}
+}
+
+static unsigned int analogix_dp_get_lane_link_training(
+				struct analogix_dp_device *dp,
+				int lane)
+{
+	u32 reg;
+
+	switch (lane) {
+	case 0:
+		reg = analogix_dp_get_lane0_link_training(dp);
+		break;
+	case 1:
+		reg = analogix_dp_get_lane1_link_training(dp);
+		break;
+	case 2:
+		reg = analogix_dp_get_lane2_link_training(dp);
+		break;
+	case 3:
+		reg = analogix_dp_get_lane3_link_training(dp);
+		break;
+	default:
+		WARN_ON(1);
+		return 0;
+	}
+
+	return reg;
+}
+
+static void analogix_dp_reduce_link_rate(struct analogix_dp_device *dp)
+{
+	analogix_dp_training_pattern_dis(dp);
+	analogix_dp_set_enhanced_mode(dp);
+
+	dp->link_train.lt_state = FAILED;
+}
+
+static void analogix_dp_get_adjust_training_lane(struct analogix_dp_device *dp,
+					u8 adjust_request[2])
+{
+	int lane, lane_count;
+	u8 voltage_swing, pre_emphasis, training_lane;
+
+	lane_count = dp->link_train.lane_count;
+	for (lane = 0; lane < lane_count; lane++) {
+		voltage_swing = analogix_dp_get_adjust_request_voltage(
+						adjust_request, lane);
+		pre_emphasis = analogix_dp_get_adjust_request_pre_emphasis(
+						adjust_request, lane);
+		training_lane = DPCD_VOLTAGE_SWING_SET(voltage_swing) |
+				DPCD_PRE_EMPHASIS_SET(pre_emphasis);
+
+		if (voltage_swing == VOLTAGE_LEVEL_3)
+			training_lane |= DP_TRAIN_MAX_SWING_REACHED;
+		if (pre_emphasis == PRE_EMPHASIS_LEVEL_3)
+			training_lane |= DP_TRAIN_MAX_PRE_EMPHASIS_REACHED;
+
+		dp->link_train.training_lane[lane] = training_lane;
+	}
+}
+
+static int analogix_dp_process_clock_recovery(struct analogix_dp_device *dp)
+{
+	int lane, lane_count, retval;
+	u8 voltage_swing, pre_emphasis, training_lane;
+	u8 link_status[2], adjust_request[2];
+
+	usleep_range(100, 101);
+
+	lane_count = dp->link_train.lane_count;
+
+	retval =  analogix_dp_read_bytes_from_dpcd(dp,
+			DP_LANE0_1_STATUS, 2, link_status);
+	if (retval)
+		return retval;
+
+	retval =  analogix_dp_read_bytes_from_dpcd(dp,
+			DP_ADJUST_REQUEST_LANE0_1, 2, adjust_request);
+	if (retval)
+		return retval;
+
+	if (analogix_dp_clock_recovery_ok(link_status, lane_count) == 0) {
+		/* set training pattern 2 for EQ */
+		analogix_dp_set_training_pattern(dp, TRAINING_PTN2);
+
+		retval = analogix_dp_write_byte_to_dpcd(dp,
+				DP_TRAINING_PATTERN_SET,
+				DP_LINK_SCRAMBLING_DISABLE |
+				DP_TRAINING_PATTERN_2);
+		if (retval)
+			return retval;
+
+		dev_info(dp->dev, "Link Training Clock Recovery success\n");
+		dp->link_train.lt_state = EQUALIZER_TRAINING;
+	} else {
+		for (lane = 0; lane < lane_count; lane++) {
+			training_lane = analogix_dp_get_lane_link_training(
+							dp, lane);
+			voltage_swing = analogix_dp_get_adjust_request_voltage(
+							adjust_request, lane);
+			pre_emphasis = analogix_dp_get_adjust_request_pre_emphasis(
+							adjust_request, lane);
+
+			if (DPCD_VOLTAGE_SWING_GET(training_lane) ==
+					voltage_swing &&
+			    DPCD_PRE_EMPHASIS_GET(training_lane) ==
+					pre_emphasis)
+				dp->link_train.cr_loop[lane]++;
+
+			if (dp->link_train.cr_loop[lane] == MAX_CR_LOOP ||
+			    voltage_swing == VOLTAGE_LEVEL_3 ||
+			    pre_emphasis == PRE_EMPHASIS_LEVEL_3) {
+				dev_err(dp->dev, "CR Max reached (%d,%d,%d)\n",
+					dp->link_train.cr_loop[lane],
+					voltage_swing, pre_emphasis);
+				analogix_dp_reduce_link_rate(dp);
+				return -EIO;
+			}
+		}
+	}
+
+	analogix_dp_get_adjust_training_lane(dp, adjust_request);
+
+	for (lane = 0; lane < lane_count; lane++)
+		analogix_dp_set_lane_link_training(dp,
+			dp->link_train.training_lane[lane], lane);
+
+	retval = analogix_dp_write_bytes_to_dpcd(dp,
+			DP_TRAINING_LANE0_SET, lane_count,
+			dp->link_train.training_lane);
+	if (retval)
+		return retval;
+
+	return retval;
+}
+
+static int analogix_dp_process_equalizer_training(struct analogix_dp_device *dp)
+{
+	int lane, lane_count, retval;
+	u32 reg;
+	u8 link_align, link_status[2], adjust_request[2];
+
+	usleep_range(400, 401);
+
+	lane_count = dp->link_train.lane_count;
+
+	retval = analogix_dp_read_bytes_from_dpcd(dp,
+			DP_LANE0_1_STATUS, 2, link_status);
+	if (retval)
+		return retval;
+
+	if (analogix_dp_clock_recovery_ok(link_status, lane_count)) {
+		analogix_dp_reduce_link_rate(dp);
+		return -EIO;
+	}
+
+	retval = analogix_dp_read_bytes_from_dpcd(dp,
+			DP_ADJUST_REQUEST_LANE0_1, 2, adjust_request);
+	if (retval)
+		return retval;
+
+	retval = analogix_dp_read_byte_from_dpcd(dp,
+			DP_LANE_ALIGN_STATUS_UPDATED, &link_align);
+	if (retval)
+		return retval;
+
+	analogix_dp_get_adjust_training_lane(dp, adjust_request);
+
+	if (!analogix_dp_channel_eq_ok(link_status, link_align, lane_count)) {
+		/* traing pattern Set to Normal */
+		analogix_dp_training_pattern_dis(dp);
+
+		dev_info(dp->dev, "Link Training success!\n");
+
+		analogix_dp_get_link_bandwidth(dp, &reg);
+		dp->link_train.link_rate = reg;
+		dev_dbg(dp->dev, "final bandwidth = %.2x\n",
+			dp->link_train.link_rate);
+
+		analogix_dp_get_lane_count(dp, &reg);
+		dp->link_train.lane_count = reg;
+		dev_dbg(dp->dev, "final lane count = %.2x\n",
+			dp->link_train.lane_count);
+
+		/* set enhanced mode if available */
+		analogix_dp_set_enhanced_mode(dp);
+		dp->link_train.lt_state = FINISHED;
+
+		return 0;
+	}
+
+	/* not all locked */
+	dp->link_train.eq_loop++;
+
+	if (dp->link_train.eq_loop > MAX_EQ_LOOP) {
+		dev_err(dp->dev, "EQ Max loop\n");
+		analogix_dp_reduce_link_rate(dp);
+		return -EIO;
+	}
+
+	for (lane = 0; lane < lane_count; lane++)
+		analogix_dp_set_lane_link_training(dp,
+			dp->link_train.training_lane[lane], lane);
+
+	retval = analogix_dp_write_bytes_to_dpcd(dp, DP_TRAINING_LANE0_SET,
+			lane_count, dp->link_train.training_lane);
+
+	return retval;
+}
+
+static void analogix_dp_get_max_rx_bandwidth(struct analogix_dp_device *dp,
+					u8 *bandwidth)
+{
+	u8 data;
+
+	/*
+	 * For DP rev.1.1, Maximum link rate of Main Link lanes
+	 * 0x06 = 1.62 Gbps, 0x0a = 2.7 Gbps
+	 */
+	analogix_dp_read_byte_from_dpcd(dp, DP_MAX_LINK_RATE, &data);
+	*bandwidth = data;
+}
+
+static void analogix_dp_get_max_rx_lane_count(struct analogix_dp_device *dp,
+					u8 *lane_count)
+{
+	u8 data;
+
+	/*
+	 * For DP rev.1.1, Maximum number of Main Link lanes
+	 * 0x01 = 1 lane, 0x02 = 2 lanes, 0x04 = 4 lanes
+	 */
+	analogix_dp_read_byte_from_dpcd(dp, DP_MAX_LANE_COUNT, &data);
+	*lane_count = DPCD_MAX_LANE_COUNT(data);
+}
+
+static void analogix_dp_init_training(struct analogix_dp_device *dp,
+			enum link_lane_count_type max_lane,
+			enum link_rate_type max_rate)
+{
+	/*
+	 * MACRO_RST must be applied after the PLL_LOCK to avoid
+	 * the DP inter pair skew issue for at least 10 us
+	 */
+	analogix_dp_reset_macro(dp);
+
+	/* Initialize by reading RX's DPCD */
+	analogix_dp_get_max_rx_bandwidth(dp, &dp->link_train.link_rate);
+	analogix_dp_get_max_rx_lane_count(dp, &dp->link_train.lane_count);
+
+	if ((dp->link_train.link_rate != LINK_RATE_1_62GBPS) &&
+	   (dp->link_train.link_rate != LINK_RATE_2_70GBPS)) {
+		dev_err(dp->dev, "Rx Max Link Rate is abnormal :%x !\n",
+			dp->link_train.link_rate);
+		dp->link_train.link_rate = LINK_RATE_1_62GBPS;
+	}
+
+	if (dp->link_train.lane_count == 0) {
+		dev_err(dp->dev, "Rx Max Lane count is abnormal :%x !\n",
+			dp->link_train.lane_count);
+		dp->link_train.lane_count = (u8)LANE_COUNT1;
+	}
+
+	/* Setup TX lane count & rate */
+	if (dp->link_train.lane_count > max_lane)
+		dp->link_train.lane_count = max_lane;
+	if (dp->link_train.link_rate > max_rate)
+		dp->link_train.link_rate = max_rate;
+
+	/* All DP analog module power up */
+	analogix_dp_set_analog_power_down(dp, POWER_ALL, 0);
+}
+
+static int analogix_dp_sw_link_training(struct analogix_dp_device *dp)
+{
+	int retval = 0, training_finished = 0;
+
+	dp->link_train.lt_state = START;
+
+	/* Process here */
+	while (!retval && !training_finished) {
+		switch (dp->link_train.lt_state) {
+		case START:
+			retval = analogix_dp_link_start(dp);
+			if (retval)
+				dev_err(dp->dev, "LT link start failed!\n");
+			break;
+		case CLOCK_RECOVERY:
+			retval = analogix_dp_process_clock_recovery(dp);
+			if (retval)
+				dev_err(dp->dev, "LT CR failed!\n");
+			break;
+		case EQUALIZER_TRAINING:
+			retval = analogix_dp_process_equalizer_training(dp);
+			if (retval)
+				dev_err(dp->dev, "LT EQ failed!\n");
+			break;
+		case FINISHED:
+			training_finished = 1;
+			break;
+		case FAILED:
+			return -EREMOTEIO;
+		}
+	}
+	if (retval)
+		dev_err(dp->dev, "eDP link training failed (%d)\n", retval);
+
+	return retval;
+}
+
+static int analogix_dp_set_link_train(struct analogix_dp_device *dp,
+				u32 count,
+				u32 bwtype)
+{
+	int i;
+	int retval;
+
+	for (i = 0; i < DP_TIMEOUT_LOOP_COUNT; i++) {
+		analogix_dp_init_training(dp, count, bwtype);
+		retval = analogix_dp_sw_link_training(dp);
+		if (retval == 0)
+			break;
+
+		usleep_range(100, 110);
+	}
+
+	return retval;
+}
+
+static int analogix_dp_config_video(struct analogix_dp_device *dp)
+{
+	int retval = 0;
+	int timeout_loop = 0;
+	int done_count = 0;
+
+	analogix_dp_config_video_slave_mode(dp);
+
+	analogix_dp_set_video_color_format(dp);
+
+	if (analogix_dp_get_pll_lock_status(dp) == PLL_UNLOCKED) {
+		dev_err(dp->dev, "PLL is not locked yet.\n");
+		return -EINVAL;
+	}
+
+	for (;;) {
+		timeout_loop++;
+		if (analogix_dp_is_slave_video_stream_clock_on(dp) == 0)
+			break;
+		if (DP_TIMEOUT_LOOP_COUNT < timeout_loop) {
+			dev_err(dp->dev, "Timeout of video streamclk ok\n");
+			return -ETIMEDOUT;
+		}
+
+		usleep_range(1, 2);
+	}
+
+	/* Set to use the register calculated M/N video */
+	analogix_dp_set_video_cr_mn(dp, CALCULATED_M, 0, 0);
+
+	/* For video bist, Video timing must be generated by register */
+	analogix_dp_set_video_timing_mode(dp, VIDEO_TIMING_FROM_CAPTURE);
+
+	/* Disable video mute */
+	analogix_dp_enable_video_mute(dp, 0);
+
+	/* Configure video slave mode */
+	analogix_dp_enable_video_master(dp, 0);
+
+	timeout_loop = 0;
+
+	for (;;) {
+		timeout_loop++;
+		if (analogix_dp_is_video_stream_on(dp) == 0) {
+			done_count++;
+			if (done_count > 10)
+				break;
+		} else if (done_count) {
+			done_count = 0;
+		}
+		if (DP_TIMEOUT_LOOP_COUNT < timeout_loop) {
+			dev_err(dp->dev, "Timeout of video streamclk ok\n");
+			return -ETIMEDOUT;
+		}
+
+		usleep_range(1000, 1001);
+	}
+
+	if (retval != 0)
+		dev_err(dp->dev, "Video stream is not detected!\n");
+
+	return retval;
+}
+
+static void analogix_dp_enable_scramble(struct analogix_dp_device *dp, bool enable)
+{
+	u8 data;
+
+	if (enable) {
+		analogix_dp_enable_scrambling(dp);
+
+		analogix_dp_read_byte_from_dpcd(dp,
+			DP_TRAINING_PATTERN_SET,
+			&data);
+		analogix_dp_write_byte_to_dpcd(dp,
+			DP_TRAINING_PATTERN_SET,
+			(u8)(data & ~DP_LINK_SCRAMBLING_DISABLE));
+	} else {
+		analogix_dp_disable_scrambling(dp);
+
+		analogix_dp_read_byte_from_dpcd(dp,
+			DP_TRAINING_PATTERN_SET,
+			&data);
+		analogix_dp_write_byte_to_dpcd(dp,
+			DP_TRAINING_PATTERN_SET,
+			(u8)(data | DP_LINK_SCRAMBLING_DISABLE));
+	}
+}
+
+static irqreturn_t analogix_dp_irq_handler(int irq, void *arg)
+{
+	struct analogix_dp_device *dp = arg;
+
+	enum dp_irq_type irq_type;
+
+	irq_type = analogix_dp_get_irq_type(dp);
+	switch (irq_type) {
+	case DP_IRQ_TYPE_HP_CABLE_IN:
+		dev_dbg(dp->dev, "Received irq - cable in\n");
+		schedule_work(&dp->hotplug_work);
+		analogix_dp_clear_hotplug_interrupts(dp);
+		break;
+	case DP_IRQ_TYPE_HP_CABLE_OUT:
+		dev_dbg(dp->dev, "Received irq - cable out\n");
+		analogix_dp_clear_hotplug_interrupts(dp);
+		break;
+	case DP_IRQ_TYPE_HP_CHANGE:
+		/*
+		 * We get these change notifications once in a while, but there
+		 * is nothing we can do with them. Just ignore it for now and
+		 * only handle cable changes.
+		 */
+		dev_dbg(dp->dev, "Received irq - hotplug change; ignoring.\n");
+		analogix_dp_clear_hotplug_interrupts(dp);
+		break;
+	default:
+		dev_err(dp->dev, "Received irq - unknown type!\n");
+		break;
+	}
+	return IRQ_HANDLED;
+}
+
+static void analogix_dp_hotplug(struct work_struct *work)
+{
+	struct analogix_dp_device *dp;
+
+	dp = container_of(work, struct analogix_dp_device, hotplug_work);
+
+	if (dp->drm_dev)
+		drm_helper_hpd_irq_event(dp->drm_dev);
+}
+
+static void analogix_dp_commit(struct analogix_dp_device *dp)
+{
+	int ret;
+
+	/* Keep the panel disabled while we configure video */
+	if (dp->plat_data->panel) {
+		if (drm_panel_disable(dp->plat_data->panel))
+			DRM_ERROR("failed to disable the panel\n");
+	}
+
+	ret = analogix_dp_detect_hpd(dp);
+	if (ret) {
+		/* Cable has been disconnected, we're done */
+		return;
+	}
+
+	ret = analogix_dp_handle_edid(dp);
+	if (ret) {
+		dev_err(dp->dev, "unable to handle edid\n");
+		return;
+	}
+
+	ret = analogix_dp_set_link_train(dp, dp->video_info->lane_count,
+					dp->video_info->link_rate);
+	if (ret) {
+		dev_err(dp->dev, "unable to do link train\n");
+		return;
+	}
+
+	analogix_dp_enable_scramble(dp, 1);
+	analogix_dp_enable_rx_to_enhanced_mode(dp, 1);
+	analogix_dp_enable_enhanced_mode(dp, 1);
+
+	analogix_dp_set_lane_count(dp, dp->video_info->lane_count);
+	analogix_dp_set_link_bandwidth(dp, dp->video_info->link_rate);
+
+	analogix_dp_init_video(dp);
+	ret = analogix_dp_config_video(dp);
+	if (ret)
+		dev_err(dp->dev, "unable to config video\n");
+
+	/* Safe to enable the panel now */
+	if (dp->plat_data->panel) {
+		if (drm_panel_enable(dp->plat_data->panel))
+			DRM_ERROR("failed to enable the panel\n");
+	}
+
+	/* Enable video */
+	analogix_dp_start_video(dp);
+}
+
+int analogix_dp_get_modes(struct drm_connector *connector)
+{
+	struct analogix_dp_device *dp = to_dp(connector);
+	int num_modes = 0;
+
+	if (dp->plat_data->panel)
+		num_modes += drm_panel_get_modes(dp->plat_data->panel);
+
+	if (dp->plat_data->get_modes)
+		num_modes += dp->plat_data->get_modes(dp->plat_data);
+
+	return num_modes;
+}
+
+static struct drm_encoder *
+analogix_dp_best_encoder(struct drm_connector *connector)
+{
+	struct analogix_dp_device *dp = to_dp(connector);
+
+	return dp->encoder;
+}
+
+static const struct drm_connector_helper_funcs analogix_dp_connector_helper_funcs = {
+	.get_modes = analogix_dp_get_modes,
+	.best_encoder = analogix_dp_best_encoder,
+};
+
+enum drm_connector_status
+analogix_dp_detect(struct drm_connector *connector, bool force)
+{
+	return connector_status_connected;
+}
+
+static void analogix_dp_connector_destroy(struct drm_connector *connector)
+{
+	drm_connector_unregister(connector);
+	drm_connector_cleanup(connector);
+}
+
+static const struct drm_connector_funcs analogix_dp_connector_funcs = {
+	.dpms = drm_atomic_helper_connector_dpms,
+	.fill_modes = drm_helper_probe_single_connector_modes,
+	.detect = analogix_dp_detect,
+	.destroy = analogix_dp_connector_destroy,
+	.reset = drm_atomic_helper_connector_reset,
+	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
+	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
+};
+
+static int analogix_dp_bridge_attach(struct drm_bridge *bridge)
+{
+	struct analogix_dp_device *dp = bridge->driver_private;
+	struct drm_encoder *encoder = dp->encoder;
+	struct drm_connector *connector = &dp->connector;
+	int ret;
+
+	if (!bridge->encoder) {
+		DRM_ERROR("Parent encoder object not found");
+		return -ENODEV;
+	}
+
+	connector->polled = DRM_CONNECTOR_POLL_HPD;
+
+	ret = drm_connector_init(dp->drm_dev, connector,
+				 &analogix_dp_connector_funcs,
+				 DRM_MODE_CONNECTOR_eDP);
+	if (ret) {
+		DRM_ERROR("Failed to initialize connector with drm\n");
+		return ret;
+	}
+
+	drm_connector_helper_add(connector,
+				 &analogix_dp_connector_helper_funcs);
+	drm_mode_connector_attach_encoder(connector, encoder);
+
+	/*
+	 * NOTE: the connector registration is implemented in analogix
+	 * platform driver, that to say connector would be exist after
+	 * plat_data->attch return, that's why we record the connector
+	 * point after plat attached.
+	 */
+	 if (dp->plat_data->attach) {
+		 ret = dp->plat_data->attach(dp->plat_data, bridge, connector);
+		 if (ret) {
+			 DRM_ERROR("Failed at platform attch func\n");
+			 return ret;
+		 }
+	}
+
+	if (dp->plat_data->panel) {
+		ret = drm_panel_attach(dp->plat_data->panel, &dp->connector);
+		if (ret) {
+			DRM_ERROR("Failed to attach panel\n");
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+static void analogix_dp_bridge_enable(struct drm_bridge *bridge)
+{
+	struct analogix_dp_device *dp = bridge->driver_private;
+
+	if (dp->dpms_mode == DRM_MODE_DPMS_ON)
+		return;
+
+	pm_runtime_get_sync(dp->dev);
+
+	if (dp->plat_data->panel) {
+		if (drm_panel_prepare(dp->plat_data->panel)) {
+			DRM_ERROR("failed to setup the panel\n");
+			return;
+		}
+	}
+
+	if (dp->plat_data->power_on)
+		dp->plat_data->power_on(dp->plat_data);
+
+	phy_power_on(dp->phy);
+	analogix_dp_init_dp(dp);
+	enable_irq(dp->irq);
+	analogix_dp_commit(dp);
+
+	dp->dpms_mode = DRM_MODE_DPMS_ON;
+}
+
+static void analogix_dp_bridge_disable(struct drm_bridge *bridge)
+{
+	struct analogix_dp_device *dp = bridge->driver_private;
+
+	if (dp->dpms_mode != DRM_MODE_DPMS_ON)
+		return;
+
+	if (dp->plat_data->panel) {
+		if (drm_panel_disable(dp->plat_data->panel)) {
+			DRM_ERROR("failed to disable the panel\n");
+			return;
+		}
+	}
+
+	disable_irq(dp->irq);
+	flush_work(&dp->hotplug_work);
+	phy_power_off(dp->phy);
+
+	if (dp->plat_data->power_off)
+		dp->plat_data->power_off(dp->plat_data);
+
+	if (dp->plat_data->panel) {
+		if (drm_panel_unprepare(dp->plat_data->panel))
+			DRM_ERROR("failed to turnoff the panel\n");
+	}
+
+	pm_runtime_put_sync(dp->dev);
+
+	dp->dpms_mode = DRM_MODE_DPMS_OFF;
+}
+
+static void analogix_dp_bridge_nop(struct drm_bridge *bridge)
+{
+	/* do nothing */
+}
+
+static const struct drm_bridge_funcs analogix_dp_bridge_funcs = {
+	.enable = analogix_dp_bridge_enable,
+	.disable = analogix_dp_bridge_disable,
+	.pre_enable = analogix_dp_bridge_nop,
+	.post_disable = analogix_dp_bridge_nop,
+	.attach = analogix_dp_bridge_attach,
+};
+
+static int analogix_dp_create_bridge(struct drm_device *drm_dev,
+				     struct analogix_dp_device *dp)
+{
+	struct drm_bridge *bridge;
+	int ret;
+
+	bridge = devm_kzalloc(drm_dev->dev, sizeof(*bridge), GFP_KERNEL);
+	if (!bridge) {
+		DRM_ERROR("failed to allocate for drm bridge\n");
+		return -ENOMEM;
+	}
+
+	dp->bridge = bridge;
+
+	dp->encoder->bridge = bridge;
+	bridge->driver_private = dp;
+	bridge->encoder = dp->encoder;
+	bridge->funcs = &analogix_dp_bridge_funcs;
+
+	ret = drm_bridge_attach(drm_dev, bridge);
+	if (ret) {
+		DRM_ERROR("failed to attach drm bridge\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static struct video_info *analogix_dp_dt_parse_pdata(struct device *dev)
+{
+	struct device_node *dp_node = dev->of_node;
+	struct video_info *dp_video_config;
+
+	dp_video_config = devm_kzalloc(dev,
+				sizeof(*dp_video_config), GFP_KERNEL);
+	if (!dp_video_config)
+		return ERR_PTR(-ENOMEM);
+
+	dp_video_config->h_sync_polarity =
+		of_property_read_bool(dp_node, "hsync-active-high");
+
+	dp_video_config->v_sync_polarity =
+		of_property_read_bool(dp_node, "vsync-active-high");
+
+	dp_video_config->interlaced =
+		of_property_read_bool(dp_node, "interlaced");
+
+	if (of_property_read_u32(dp_node, "samsung,color-space",
+				&dp_video_config->color_space)) {
+		dev_err(dev, "failed to get color-space\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	if (of_property_read_u32(dp_node, "samsung,dynamic-range",
+				&dp_video_config->dynamic_range)) {
+		dev_err(dev, "failed to get dynamic-range\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	if (of_property_read_u32(dp_node, "samsung,ycbcr-coeff",
+				&dp_video_config->ycbcr_coeff)) {
+		dev_err(dev, "failed to get ycbcr-coeff\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	if (of_property_read_u32(dp_node, "samsung,color-depth",
+				&dp_video_config->color_depth)) {
+		dev_err(dev, "failed to get color-depth\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	if (of_property_read_u32(dp_node, "samsung,link-rate",
+				&dp_video_config->link_rate)) {
+		dev_err(dev, "failed to get link-rate\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	if (of_property_read_u32(dp_node, "samsung,lane-count",
+				&dp_video_config->lane_count)) {
+		dev_err(dev, "failed to get lane-count\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	return dp_video_config;
+}
+
+int analogix_dp_bind(struct device *dev, struct drm_device *drm_dev,
+		     struct analogix_dp_plat_data *plat_data)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct analogix_dp_device *dp;
+	struct resource *res;
+	unsigned int irq_flags;
+	int ret;
+
+	if (!plat_data) {
+		dev_err(dev, "Invalided input plat_data\n");
+		return -EINVAL;
+	}
+
+	dp = devm_kzalloc(dev, sizeof(struct analogix_dp_device), GFP_KERNEL);
+	if (!dp)
+		return -ENOMEM;
+
+	dev_set_drvdata(dev, dp);
+
+	dp->dev = &pdev->dev;
+	dp->dpms_mode = DRM_MODE_DPMS_OFF;
+
+	/*
+	 * platform dp driver need containor_of the plat_data to get
+	 * the driver private data, so we need to store the point of
+	 * plat_data, not the context of plat_data.
+	 */
+	dp->plat_data = plat_data;
+
+	dp->video_info = analogix_dp_dt_parse_pdata(&pdev->dev);
+	if (IS_ERR(dp->video_info))
+		return PTR_ERR(dp->video_info);
+
+	dp->phy = devm_phy_get(dp->dev, "dp");
+	if (IS_ERR(dp->phy)) {
+		dev_err(dp->dev, "no DP phy configured\n");
+		ret = PTR_ERR(dp->phy);
+		if (ret) {
+			/*
+			 * phy itself is not enabled, so we can move forward
+			 * assigning NULL to phy pointer.
+			 */
+			if (ret == -ENOSYS || ret == -ENODEV)
+				dp->phy = NULL;
+			else
+				return ret;
+		}
+	}
+
+	dp->clock = devm_clk_get(&pdev->dev, "dp");
+	if (IS_ERR(dp->clock)) {
+		dev_err(&pdev->dev, "failed to get clock\n");
+		return PTR_ERR(dp->clock);
+	}
+
+	clk_prepare_enable(dp->clock);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+
+	dp->reg_base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(dp->reg_base))
+		return PTR_ERR(dp->reg_base);
+
+	dp->hpd_gpio = of_get_named_gpio(dev->of_node, "hpd-gpios", 0);
+	if (!gpio_is_valid(dp->hpd_gpio))
+		dp->hpd_gpio = of_get_named_gpio(dev->of_node,
+						 "samsung,hpd-gpio", 0);
+
+	if (gpio_is_valid(dp->hpd_gpio)) {
+		/*
+		 * Set up the hotplug GPIO from the device tree as an interrupt.
+		 * Simply specifying a different interrupt in the device tree
+		 * doesn't work since we handle hotplug rather differently when
+		 * using a GPIO.  We also need the actual GPIO specifier so
+		 * that we can get the current state of the GPIO.
+		 */
+		ret = devm_gpio_request_one(&pdev->dev, dp->hpd_gpio, GPIOF_IN,
+					    "hpd_gpio");
+		if (ret) {
+			dev_err(&pdev->dev, "failed to get hpd gpio\n");
+			return ret;
+		}
+		dp->irq = gpio_to_irq(dp->hpd_gpio);
+		irq_flags = IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING;
+	} else {
+		dp->hpd_gpio = -ENODEV;
+		dp->irq = platform_get_irq(pdev, 0);
+		irq_flags = 0;
+	}
+
+	if (dp->irq == -ENXIO) {
+		dev_err(&pdev->dev, "failed to get irq\n");
+		return -ENODEV;
+	}
+
+	INIT_WORK(&dp->hotplug_work, analogix_dp_hotplug);
+
+	pm_runtime_enable(dev);
+
+	ret = devm_request_irq(&pdev->dev, dp->irq, analogix_dp_irq_handler,
+			irq_flags, "analogix-dp", dp);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to request irq\n");
+		goto err_disable_pm_runtime;
+	}
+	disable_irq(dp->irq);
+
+	dp->drm_dev = drm_dev;
+	dp->encoder = dp->plat_data->encoder;
+
+	ret = analogix_dp_create_bridge(drm_dev, dp);
+	if (ret) {
+		DRM_ERROR("failed to create bridge (%d)\n", ret);
+		drm_encoder_cleanup(dp->encoder);
+		goto err_disable_pm_runtime;
+	}
+
+	return 0;
+
+err_disable_pm_runtime:
+	pm_runtime_disable(dev);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(analogix_dp_bind);
+
+void analogix_dp_unbind(struct device *dev, struct device *master,
+			void *data)
+{
+	struct analogix_dp_device *dp = dev_get_drvdata(dev);
+
+	analogix_dp_bridge_disable(dp->bridge);
+	pm_runtime_disable(dev);
+}
+EXPORT_SYMBOL_GPL(analogix_dp_unbind);
+
+#ifdef CONFIG_PM
+int analogix_dp_suspend(struct device *dev)
+{
+	struct analogix_dp_device *dp = dev_get_drvdata(dev);
+
+	clk_disable_unprepare(dp->clock);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(analogix_dp_suspend);
+
+int analogix_dp_resume(struct device *dev)
+{
+	struct analogix_dp_device *dp = dev_get_drvdata(dev);
+	int ret;
+
+	ret = clk_prepare_enable(dp->clock);
+	if (ret < 0) {
+		DRM_ERROR("Failed to prepare_enable the clock clk [%d]\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(analogix_dp_resume);
+#endif
+
+MODULE_AUTHOR("Jingoo Han <jg1.han@samsung.com>");
+MODULE_DESCRIPTION("Analogix DP Core Driver");
+MODULE_LICENSE("GPL v2");