[PATCH v6 2/4] Revert "drm/tegra: Move drm_dp_link helpers to Tegra DRM"

allen allen.chen at ite.com.tw
Mon Jan 20 02:44:32 UTC 2020


IT6505 driver ite-it6505.c file using drm_dp_link helpers, so revert.
This reverts commit 9a42c7c647a9ad0f7ebb147a52eda3dcb7c84292.

Signed-off-by: Allen Chen <allen.chen at ite.com.tw>
---
 drivers/gpu/drm/drm_dp_helper.c | 128 ++++++
 drivers/gpu/drm/tegra/Makefile  |   1 -
 drivers/gpu/drm/tegra/dp.c      | 876 ----------------------------------------
 drivers/gpu/drm/tegra/dp.h      | 177 --------
 drivers/gpu/drm/tegra/dpaux.c   |   1 -
 drivers/gpu/drm/tegra/sor.c     |   1 -
 include/drm/drm_dp_helper.h     |  16 +
 7 files changed, 144 insertions(+), 1056 deletions(-)
 delete mode 100644 drivers/gpu/drm/tegra/dp.c
 delete mode 100644 drivers/gpu/drm/tegra/dp.h

diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c
index 2c7870a..f567141 100644
--- a/drivers/gpu/drm/drm_dp_helper.c
+++ b/drivers/gpu/drm/drm_dp_helper.c
@@ -352,6 +352,134 @@ int drm_dp_dpcd_read_link_status(struct drm_dp_aux *aux,
 EXPORT_SYMBOL(drm_dp_dpcd_read_link_status);
 
 /**
+ * drm_dp_link_probe() - probe a DisplayPort link for capabilities
+ * @aux: DisplayPort AUX channel
+ * @link: pointer to structure in which to return link capabilities
+ *
+ * The structure filled in by this function can usually be passed directly
+ * into drm_dp_link_power_up() and drm_dp_link_configure() to power up and
+ * configure the link based on the link's capabilities.
+ *
+ * Returns 0 on success or a negative error code on failure.
+ */
+int drm_dp_link_probe(struct drm_dp_aux *aux, struct drm_dp_link *link)
+{
+	u8 values[3];
+	int err;
+
+	memset(link, 0, sizeof(*link));
+
+	err = drm_dp_dpcd_read(aux, DP_DPCD_REV, values, sizeof(values));
+	if (err < 0)
+		return err;
+
+	link->revision = values[0];
+	link->rate = drm_dp_bw_code_to_link_rate(values[1]);
+	link->num_lanes = values[2] & DP_MAX_LANE_COUNT_MASK;
+
+	if (values[2] & DP_ENHANCED_FRAME_CAP)
+		link->capabilities |= DP_LINK_CAP_ENHANCED_FRAMING;
+
+	return 0;
+}
+EXPORT_SYMBOL(drm_dp_link_probe);
+
+/**
+ * drm_dp_link_power_up() - power up a DisplayPort link
+ * @aux: DisplayPort AUX channel
+ * @link: pointer to a structure containing the link configuration
+ *
+ * Returns 0 on success or a negative error code on failure.
+ */
+int drm_dp_link_power_up(struct drm_dp_aux *aux, struct drm_dp_link *link)
+{
+	u8 value;
+	int err;
+
+	/* DP_SET_POWER register is only available on DPCD v1.1 and later */
+	if (link->revision < 0x11)
+		return 0;
+
+	err = drm_dp_dpcd_readb(aux, DP_SET_POWER, &value);
+	if (err < 0)
+		return err;
+
+	value &= ~DP_SET_POWER_MASK;
+	value |= DP_SET_POWER_D0;
+
+	err = drm_dp_dpcd_writeb(aux, DP_SET_POWER, value);
+	if (err < 0)
+		return err;
+
+	/*
+	 * According to the DP 1.1 specification, a "Sink Device must exit the
+	 * power saving state within 1 ms" (Section 2.5.3.1, Table 5-52, "Sink
+	 * Control Field" (register 0x600).
+	 */
+	usleep_range(1000, 2000);
+
+	return 0;
+}
+EXPORT_SYMBOL(drm_dp_link_power_up);
+
+/**
+ * drm_dp_link_power_down() - power down a DisplayPort link
+ * @aux: DisplayPort AUX channel
+ * @link: pointer to a structure containing the link configuration
+ *
+ * Returns 0 on success or a negative error code on failure.
+ */
+int drm_dp_link_power_down(struct drm_dp_aux *aux, struct drm_dp_link *link)
+{
+	u8 value;
+	int err;
+
+	/* DP_SET_POWER register is only available on DPCD v1.1 and later */
+	if (link->revision < 0x11)
+		return 0;
+
+	err = drm_dp_dpcd_readb(aux, DP_SET_POWER, &value);
+	if (err < 0)
+		return err;
+
+	value &= ~DP_SET_POWER_MASK;
+	value |= DP_SET_POWER_D3;
+
+	err = drm_dp_dpcd_writeb(aux, DP_SET_POWER, value);
+	if (err < 0)
+		return err;
+
+	return 0;
+}
+EXPORT_SYMBOL(drm_dp_link_power_down);
+
+/**
+ * drm_dp_link_configure() - configure a DisplayPort link
+ * @aux: DisplayPort AUX channel
+ * @link: pointer to a structure containing the link configuration
+ *
+ * Returns 0 on success or a negative error code on failure.
+ */
+int drm_dp_link_configure(struct drm_dp_aux *aux, struct drm_dp_link *link)
+{
+	u8 values[2];
+	int err;
+
+	values[0] = drm_dp_link_rate_to_bw_code(link->rate);
+	values[1] = link->num_lanes;
+
+	if (link->capabilities & DP_LINK_CAP_ENHANCED_FRAMING)
+		values[1] |= DP_LANE_COUNT_ENHANCED_FRAME_EN;
+
+	err = drm_dp_dpcd_write(aux, DP_LINK_BW_SET, values, sizeof(values));
+	if (err < 0)
+		return err;
+
+	return 0;
+}
+EXPORT_SYMBOL(drm_dp_link_configure);
+
+/**
  * drm_dp_downstream_max_clock() - extract branch device max
  *                                 pixel rate for legacy VGA
  *                                 converter or max TMDS clock
diff --git a/drivers/gpu/drm/tegra/Makefile b/drivers/gpu/drm/tegra/Makefile
index d6cf202..33c463e 100644
--- a/drivers/gpu/drm/tegra/Makefile
+++ b/drivers/gpu/drm/tegra/Makefile
@@ -5,7 +5,6 @@ tegra-drm-y := \
 	drm.o \
 	gem.o \
 	fb.o \
-	dp.o \
 	hub.o \
 	plane.o \
 	dc.o \
diff --git a/drivers/gpu/drm/tegra/dp.c b/drivers/gpu/drm/tegra/dp.c
deleted file mode 100644
index 70dfb7d..00000000
--- a/drivers/gpu/drm/tegra/dp.c
+++ /dev/null
@@ -1,876 +0,0 @@
-// SPDX-License-Identifier: MIT
-/*
- * Copyright (C) 2013-2019 NVIDIA Corporation
- * Copyright (C) 2015 Rob Clark
- */
-
-#include <drm/drm_crtc.h>
-#include <drm/drm_dp_helper.h>
-#include <drm/drm_print.h>
-
-#include "dp.h"
-
-static const u8 drm_dp_edp_revisions[] = { 0x11, 0x12, 0x13, 0x14 };
-
-static void drm_dp_link_caps_reset(struct drm_dp_link_caps *caps)
-{
-	caps->enhanced_framing = false;
-	caps->tps3_supported = false;
-	caps->fast_training = false;
-	caps->channel_coding = false;
-	caps->alternate_scrambler_reset = false;
-}
-
-void drm_dp_link_caps_copy(struct drm_dp_link_caps *dest,
-			   const struct drm_dp_link_caps *src)
-{
-	dest->enhanced_framing = src->enhanced_framing;
-	dest->tps3_supported = src->tps3_supported;
-	dest->fast_training = src->fast_training;
-	dest->channel_coding = src->channel_coding;
-	dest->alternate_scrambler_reset = src->alternate_scrambler_reset;
-}
-
-static void drm_dp_link_reset(struct drm_dp_link *link)
-{
-	unsigned int i;
-
-	if (!link)
-		return;
-
-	link->revision = 0;
-	link->max_rate = 0;
-	link->max_lanes = 0;
-
-	drm_dp_link_caps_reset(&link->caps);
-	link->aux_rd_interval.cr = 0;
-	link->aux_rd_interval.ce = 0;
-	link->edp = 0;
-
-	link->rate = 0;
-	link->lanes = 0;
-
-	for (i = 0; i < DP_MAX_SUPPORTED_RATES; i++)
-		link->rates[i] = 0;
-
-	link->num_rates = 0;
-}
-
-/**
- * drm_dp_link_add_rate() - add a rate to the list of supported rates
- * @link: the link to add the rate to
- * @rate: the rate to add
- *
- * Add a link rate to the list of supported link rates.
- *
- * Returns:
- * 0 on success or one of the following negative error codes on failure:
- * - ENOSPC if the maximum number of supported rates has been reached
- * - EEXISTS if the link already supports this rate
- *
- * See also:
- * drm_dp_link_remove_rate()
- */
-int drm_dp_link_add_rate(struct drm_dp_link *link, unsigned long rate)
-{
-	unsigned int i, pivot;
-
-	if (link->num_rates == DP_MAX_SUPPORTED_RATES)
-		return -ENOSPC;
-
-	for (pivot = 0; pivot < link->num_rates; pivot++)
-		if (rate <= link->rates[pivot])
-			break;
-
-	if (pivot != link->num_rates && rate == link->rates[pivot])
-		return -EEXIST;
-
-	for (i = link->num_rates; i > pivot; i--)
-		link->rates[i] = link->rates[i - 1];
-
-	link->rates[pivot] = rate;
-	link->num_rates++;
-
-	return 0;
-}
-
-/**
- * drm_dp_link_remove_rate() - remove a rate from the list of supported rates
- * @link: the link from which to remove the rate
- * @rate: the rate to remove
- *
- * Removes a link rate from the list of supported link rates.
- *
- * Returns:
- * 0 on success or one of the following negative error codes on failure:
- * - EINVAL if the specified rate is not among the supported rates
- *
- * See also:
- * drm_dp_link_add_rate()
- */
-int drm_dp_link_remove_rate(struct drm_dp_link *link, unsigned long rate)
-{
-	unsigned int i;
-
-	for (i = 0; i < link->num_rates; i++)
-		if (rate == link->rates[i])
-			break;
-
-	if (i == link->num_rates)
-		return -EINVAL;
-
-	link->num_rates--;
-
-	while (i < link->num_rates) {
-		link->rates[i] = link->rates[i + 1];
-		i++;
-	}
-
-	return 0;
-}
-
-/**
- * drm_dp_link_update_rates() - normalize the supported link rates array
- * @link: the link for which to normalize the supported link rates
- *
- * Users should call this function after they've manually modified the array
- * of supported link rates. This function removes any stale entries, compacts
- * the array and updates the supported link rate count. Note that calling the
- * drm_dp_link_remove_rate() function already does this janitorial work.
- *
- * See also:
- * drm_dp_link_add_rate(), drm_dp_link_remove_rate()
- */
-void drm_dp_link_update_rates(struct drm_dp_link *link)
-{
-	unsigned int i, count = 0;
-
-	for (i = 0; i < link->num_rates; i++) {
-		if (link->rates[i] != 0)
-			link->rates[count++] = link->rates[i];
-	}
-
-	for (i = count; i < link->num_rates; i++)
-		link->rates[i] = 0;
-
-	link->num_rates = count;
-}
-
-/**
- * drm_dp_link_probe() - probe a DisplayPort link for capabilities
- * @aux: DisplayPort AUX channel
- * @link: pointer to structure in which to return link capabilities
- *
- * The structure filled in by this function can usually be passed directly
- * into drm_dp_link_power_up() and drm_dp_link_configure() to power up and
- * configure the link based on the link's capabilities.
- *
- * Returns 0 on success or a negative error code on failure.
- */
-int drm_dp_link_probe(struct drm_dp_aux *aux, struct drm_dp_link *link)
-{
-	u8 dpcd[DP_RECEIVER_CAP_SIZE], value;
-	unsigned int rd_interval;
-	int err;
-
-	drm_dp_link_reset(link);
-
-	err = drm_dp_dpcd_read(aux, DP_DPCD_REV, dpcd, sizeof(dpcd));
-	if (err < 0)
-		return err;
-
-	link->revision = dpcd[DP_DPCD_REV];
-	link->max_rate = drm_dp_max_link_rate(dpcd);
-	link->max_lanes = drm_dp_max_lane_count(dpcd);
-
-	link->caps.enhanced_framing = drm_dp_enhanced_frame_cap(dpcd);
-	link->caps.tps3_supported = drm_dp_tps3_supported(dpcd);
-	link->caps.fast_training = drm_dp_fast_training_cap(dpcd);
-	link->caps.channel_coding = drm_dp_channel_coding_supported(dpcd);
-
-	if (drm_dp_alternate_scrambler_reset_cap(dpcd)) {
-		link->caps.alternate_scrambler_reset = true;
-
-		err = drm_dp_dpcd_readb(aux, DP_EDP_DPCD_REV, &value);
-		if (err < 0)
-			return err;
-
-		if (value >= ARRAY_SIZE(drm_dp_edp_revisions))
-			DRM_ERROR("unsupported eDP version: %02x\n", value);
-		else
-			link->edp = drm_dp_edp_revisions[value];
-	}
-
-	/*
-	 * The DPCD stores the AUX read interval in units of 4 ms. There are
-	 * two special cases:
-	 *
-	 *   1) if the TRAINING_AUX_RD_INTERVAL field is 0, the clock recovery
-	 *      and channel equalization should use 100 us or 400 us AUX read
-	 *      intervals, respectively
-	 *
-	 *   2) for DP v1.4 and above, clock recovery should always use 100 us
-	 *      AUX read intervals
-	 */
-	rd_interval = dpcd[DP_TRAINING_AUX_RD_INTERVAL] &
-			   DP_TRAINING_AUX_RD_MASK;
-
-	if (rd_interval > 4) {
-		DRM_DEBUG_KMS("AUX interval %u out of range (max. 4)\n",
-			      rd_interval);
-		rd_interval = 4;
-	}
-
-	rd_interval *= 4 * USEC_PER_MSEC;
-
-	if (rd_interval == 0 || link->revision >= DP_DPCD_REV_14)
-		link->aux_rd_interval.cr = 100;
-
-	if (rd_interval == 0)
-		link->aux_rd_interval.ce = 400;
-
-	link->rate = link->max_rate;
-	link->lanes = link->max_lanes;
-
-	/* Parse SUPPORTED_LINK_RATES from eDP 1.4 */
-	if (link->edp >= 0x14) {
-		u8 supported_rates[DP_MAX_SUPPORTED_RATES * 2];
-		unsigned int i;
-		u16 rate;
-
-		err = drm_dp_dpcd_read(aux, DP_SUPPORTED_LINK_RATES,
-				       supported_rates,
-				       sizeof(supported_rates));
-		if (err < 0)
-			return err;
-
-		for (i = 0; i < DP_MAX_SUPPORTED_RATES; i++) {
-			rate = supported_rates[i * 2 + 1] << 8 |
-			       supported_rates[i * 2 + 0];
-
-			drm_dp_link_add_rate(link, rate * 200);
-		}
-	}
-
-	return 0;
-}
-
-/**
- * drm_dp_link_power_up() - power up a DisplayPort link
- * @aux: DisplayPort AUX channel
- * @link: pointer to a structure containing the link configuration
- *
- * Returns 0 on success or a negative error code on failure.
- */
-int drm_dp_link_power_up(struct drm_dp_aux *aux, struct drm_dp_link *link)
-{
-	u8 value;
-	int err;
-
-	/* DP_SET_POWER register is only available on DPCD v1.1 and later */
-	if (link->revision < 0x11)
-		return 0;
-
-	err = drm_dp_dpcd_readb(aux, DP_SET_POWER, &value);
-	if (err < 0)
-		return err;
-
-	value &= ~DP_SET_POWER_MASK;
-	value |= DP_SET_POWER_D0;
-
-	err = drm_dp_dpcd_writeb(aux, DP_SET_POWER, value);
-	if (err < 0)
-		return err;
-
-	/*
-	 * According to the DP 1.1 specification, a "Sink Device must exit the
-	 * power saving state within 1 ms" (Section 2.5.3.1, Table 5-52, "Sink
-	 * Control Field" (register 0x600).
-	 */
-	usleep_range(1000, 2000);
-
-	return 0;
-}
-
-/**
- * drm_dp_link_power_down() - power down a DisplayPort link
- * @aux: DisplayPort AUX channel
- * @link: pointer to a structure containing the link configuration
- *
- * Returns 0 on success or a negative error code on failure.
- */
-int drm_dp_link_power_down(struct drm_dp_aux *aux, struct drm_dp_link *link)
-{
-	u8 value;
-	int err;
-
-	/* DP_SET_POWER register is only available on DPCD v1.1 and later */
-	if (link->revision < 0x11)
-		return 0;
-
-	err = drm_dp_dpcd_readb(aux, DP_SET_POWER, &value);
-	if (err < 0)
-		return err;
-
-	value &= ~DP_SET_POWER_MASK;
-	value |= DP_SET_POWER_D3;
-
-	err = drm_dp_dpcd_writeb(aux, DP_SET_POWER, value);
-	if (err < 0)
-		return err;
-
-	return 0;
-}
-
-/**
- * drm_dp_link_configure() - configure a DisplayPort link
- * @aux: DisplayPort AUX channel
- * @link: pointer to a structure containing the link configuration
- *
- * Returns 0 on success or a negative error code on failure.
- */
-int drm_dp_link_configure(struct drm_dp_aux *aux, struct drm_dp_link *link)
-{
-	u8 values[2], value;
-	int err;
-
-	if (link->ops && link->ops->configure) {
-		err = link->ops->configure(link);
-		if (err < 0) {
-			DRM_ERROR("failed to configure DP link: %d\n", err);
-			return err;
-		}
-	}
-
-	values[0] = drm_dp_link_rate_to_bw_code(link->rate);
-	values[1] = link->lanes;
-
-	if (link->caps.enhanced_framing)
-		values[1] |= DP_LANE_COUNT_ENHANCED_FRAME_EN;
-
-	err = drm_dp_dpcd_write(aux, DP_LINK_BW_SET, values, sizeof(values));
-	if (err < 0)
-		return err;
-
-	if (link->caps.channel_coding)
-		value = DP_SET_ANSI_8B10B;
-	else
-		value = 0;
-
-	err = drm_dp_dpcd_writeb(aux, DP_MAIN_LINK_CHANNEL_CODING_SET, value);
-	if (err < 0)
-		return err;
-
-	if (link->caps.alternate_scrambler_reset) {
-		err = drm_dp_dpcd_writeb(aux, DP_EDP_CONFIGURATION_SET,
-					 DP_ALTERNATE_SCRAMBLER_RESET_ENABLE);
-		if (err < 0)
-			return err;
-	}
-
-	return 0;
-}
-
-/**
- * drm_dp_link_choose() - choose the lowest possible configuration for a mode
- * @link: DRM DP link object
- * @mode: DRM display mode
- * @info: DRM display information
- *
- * According to the eDP specification, a source should select a configuration
- * with the lowest number of lanes and the lowest possible link rate that can
- * match the bitrate requirements of a video mode. However it must ensure not
- * to exceed the capabilities of the sink.
- *
- * Returns: 0 on success or a negative error code on failure.
- */
-int drm_dp_link_choose(struct drm_dp_link *link,
-		       const struct drm_display_mode *mode,
-		       const struct drm_display_info *info)
-{
-	/* available link symbol clock rates */
-	static const unsigned int rates[3] = { 162000, 270000, 540000 };
-	/* available number of lanes */
-	static const unsigned int lanes[3] = { 1, 2, 4 };
-	unsigned long requirement, capacity;
-	unsigned int rate = link->max_rate;
-	unsigned int i, j;
-
-	/* bandwidth requirement */
-	requirement = mode->clock * info->bpc * 3;
-
-	for (i = 0; i < ARRAY_SIZE(lanes) && lanes[i] <= link->max_lanes; i++) {
-		for (j = 0; j < ARRAY_SIZE(rates) && rates[j] <= rate; j++) {
-			/*
-			 * Capacity for this combination of lanes and rate,
-			 * factoring in the ANSI 8B/10B encoding.
-			 *
-			 * Link rates in the DRM DP helpers are really link
-			 * symbol frequencies, so a tenth of the actual rate
-			 * of the link.
-			 */
-			capacity = lanes[i] * (rates[j] * 10) * 8 / 10;
-
-			if (capacity >= requirement) {
-				DRM_DEBUG_KMS("using %u lanes at %u kHz (%lu/%lu kbps)\n",
-					      lanes[i], rates[j], requirement,
-					      capacity);
-				link->lanes = lanes[i];
-				link->rate = rates[j];
-				return 0;
-			}
-		}
-	}
-
-	return -ERANGE;
-}
-
-/**
- * DOC: Link training
- *
- * These functions contain common logic and helpers to implement DisplayPort
- * link training.
- */
-
-/**
- * drm_dp_link_train_init() - initialize DisplayPort link training state
- * @train: DisplayPort link training state
- */
-void drm_dp_link_train_init(struct drm_dp_link_train *train)
-{
-	struct drm_dp_link_train_set *request = &train->request;
-	struct drm_dp_link_train_set *adjust = &train->adjust;
-	unsigned int i;
-
-	for (i = 0; i < 4; i++) {
-		request->voltage_swing[i] = 0;
-		adjust->voltage_swing[i] = 0;
-
-		request->pre_emphasis[i] = 0;
-		adjust->pre_emphasis[i] = 0;
-
-		request->post_cursor[i] = 0;
-		adjust->post_cursor[i] = 0;
-	}
-
-	train->pattern = DP_TRAINING_PATTERN_DISABLE;
-	train->clock_recovered = false;
-	train->channel_equalized = false;
-}
-
-static bool drm_dp_link_train_valid(const struct drm_dp_link_train *train)
-{
-	return train->clock_recovered && train->channel_equalized;
-}
-
-static int drm_dp_link_apply_training(struct drm_dp_link *link)
-{
-	struct drm_dp_link_train_set *request = &link->train.request;
-	unsigned int lanes = link->lanes, *vs, *pe, *pc, i;
-	struct drm_dp_aux *aux = link->aux;
-	u8 values[4], pattern = 0;
-	int err;
-
-	err = link->ops->apply_training(link);
-	if (err < 0) {
-		DRM_ERROR("failed to apply link training: %d\n", err);
-		return err;
-	}
-
-	vs = request->voltage_swing;
-	pe = request->pre_emphasis;
-	pc = request->post_cursor;
-
-	/* write currently selected voltage-swing and pre-emphasis levels */
-	for (i = 0; i < lanes; i++)
-		values[i] = DP_TRAIN_VOLTAGE_SWING_LEVEL(vs[i]) |
-			    DP_TRAIN_PRE_EMPHASIS_LEVEL(pe[i]);
-
-	err = drm_dp_dpcd_write(aux, DP_TRAINING_LANE0_SET, values, lanes);
-	if (err < 0) {
-		DRM_ERROR("failed to set training parameters: %d\n", err);
-		return err;
-	}
-
-	/* write currently selected post-cursor level (if supported) */
-	if (link->revision >= 0x12 && link->rate == 540000) {
-		values[0] = values[1] = 0;
-
-		for (i = 0; i < lanes; i++)
-			values[i / 2] |= DP_LANE_POST_CURSOR(i, pc[i]);
-
-		err = drm_dp_dpcd_write(aux, DP_TRAINING_LANE0_1_SET2, values,
-					DIV_ROUND_UP(lanes, 2));
-		if (err < 0) {
-			DRM_ERROR("failed to set post-cursor: %d\n", err);
-			return err;
-		}
-	}
-
-	/* write link pattern */
-	if (link->train.pattern != DP_TRAINING_PATTERN_DISABLE)
-		pattern |= DP_LINK_SCRAMBLING_DISABLE;
-
-	pattern |= link->train.pattern;
-
-	err = drm_dp_dpcd_writeb(aux, DP_TRAINING_PATTERN_SET, pattern);
-	if (err < 0) {
-		DRM_ERROR("failed to set training pattern: %d\n", err);
-		return err;
-	}
-
-	return 0;
-}
-
-static void drm_dp_link_train_wait(struct drm_dp_link *link)
-{
-	unsigned long min = 0;
-
-	switch (link->train.pattern) {
-	case DP_TRAINING_PATTERN_1:
-		min = link->aux_rd_interval.cr;
-		break;
-
-	case DP_TRAINING_PATTERN_2:
-	case DP_TRAINING_PATTERN_3:
-		min = link->aux_rd_interval.ce;
-		break;
-
-	default:
-		break;
-	}
-
-	if (min > 0)
-		usleep_range(min, 2 * min);
-}
-
-static void drm_dp_link_get_adjustments(struct drm_dp_link *link,
-					u8 status[DP_LINK_STATUS_SIZE])
-{
-	struct drm_dp_link_train_set *adjust = &link->train.adjust;
-	unsigned int i;
-
-	for (i = 0; i < link->lanes; i++) {
-		adjust->voltage_swing[i] =
-			drm_dp_get_adjust_request_voltage(status, i) >>
-				DP_TRAIN_VOLTAGE_SWING_SHIFT;
-
-		adjust->pre_emphasis[i] =
-			drm_dp_get_adjust_request_pre_emphasis(status, i) >>
-				DP_TRAIN_PRE_EMPHASIS_SHIFT;
-
-		adjust->post_cursor[i] =
-			drm_dp_get_adjust_request_post_cursor(status, i);
-	}
-}
-
-static void drm_dp_link_train_adjust(struct drm_dp_link_train *train)
-{
-	struct drm_dp_link_train_set *request = &train->request;
-	struct drm_dp_link_train_set *adjust = &train->adjust;
-	unsigned int i;
-
-	for (i = 0; i < 4; i++)
-		if (request->voltage_swing[i] != adjust->voltage_swing[i])
-			request->voltage_swing[i] = adjust->voltage_swing[i];
-
-	for (i = 0; i < 4; i++)
-		if (request->pre_emphasis[i] != adjust->pre_emphasis[i])
-			request->pre_emphasis[i] = adjust->pre_emphasis[i];
-
-	for (i = 0; i < 4; i++)
-		if (request->post_cursor[i] != adjust->post_cursor[i])
-			request->post_cursor[i] = adjust->post_cursor[i];
-}
-
-static int drm_dp_link_recover_clock(struct drm_dp_link *link)
-{
-	u8 status[DP_LINK_STATUS_SIZE];
-	int err;
-
-	err = drm_dp_link_apply_training(link);
-	if (err < 0)
-		return err;
-
-	drm_dp_link_train_wait(link);
-
-	err = drm_dp_dpcd_read_link_status(link->aux, status);
-	if (err < 0) {
-		DRM_ERROR("failed to read link status: %d\n", err);
-		return err;
-	}
-
-	if (!drm_dp_clock_recovery_ok(status, link->lanes))
-		drm_dp_link_get_adjustments(link, status);
-	else
-		link->train.clock_recovered = true;
-
-	return 0;
-}
-
-static int drm_dp_link_clock_recovery(struct drm_dp_link *link)
-{
-	unsigned int repeat;
-	int err;
-
-	/* start clock recovery using training pattern 1 */
-	link->train.pattern = DP_TRAINING_PATTERN_1;
-
-	for (repeat = 1; repeat < 5; repeat++) {
-		err = drm_dp_link_recover_clock(link);
-		if (err < 0) {
-			DRM_ERROR("failed to recover clock: %d\n", err);
-			return err;
-		}
-
-		if (link->train.clock_recovered)
-			break;
-
-		drm_dp_link_train_adjust(&link->train);
-	}
-
-	return 0;
-}
-
-static int drm_dp_link_equalize_channel(struct drm_dp_link *link)
-{
-	struct drm_dp_aux *aux = link->aux;
-	u8 status[DP_LINK_STATUS_SIZE];
-	int err;
-
-	err = drm_dp_link_apply_training(link);
-	if (err < 0)
-		return err;
-
-	drm_dp_link_train_wait(link);
-
-	err = drm_dp_dpcd_read_link_status(aux, status);
-	if (err < 0) {
-		DRM_ERROR("failed to read link status: %d\n", err);
-		return err;
-	}
-
-	if (!drm_dp_clock_recovery_ok(status, link->lanes)) {
-		DRM_ERROR("clock recovery lost while equalizing channel\n");
-		link->train.clock_recovered = false;
-		return 0;
-	}
-
-	if (!drm_dp_channel_eq_ok(status, link->lanes))
-		drm_dp_link_get_adjustments(link, status);
-	else
-		link->train.channel_equalized = true;
-
-	return 0;
-}
-
-static int drm_dp_link_channel_equalization(struct drm_dp_link *link)
-{
-	unsigned int repeat;
-	int err;
-
-	/* start channel equalization using pattern 2 or 3 */
-	if (link->caps.tps3_supported)
-		link->train.pattern = DP_TRAINING_PATTERN_3;
-	else
-		link->train.pattern = DP_TRAINING_PATTERN_2;
-
-	for (repeat = 1; repeat < 5; repeat++) {
-		err = drm_dp_link_equalize_channel(link);
-		if (err < 0) {
-			DRM_ERROR("failed to equalize channel: %d\n", err);
-			return err;
-		}
-
-		if (link->train.channel_equalized)
-			break;
-
-		drm_dp_link_train_adjust(&link->train);
-	}
-
-	return 0;
-}
-
-static int drm_dp_link_downgrade(struct drm_dp_link *link)
-{
-	switch (link->rate) {
-	case 162000:
-		return -EINVAL;
-
-	case 270000:
-		link->rate = 162000;
-		break;
-
-	case 540000:
-		link->rate = 270000;
-		return 0;
-	}
-
-	return 0;
-}
-
-static void drm_dp_link_train_disable(struct drm_dp_link *link)
-{
-	int err;
-
-	link->train.pattern = DP_TRAINING_PATTERN_DISABLE;
-
-	err = drm_dp_link_apply_training(link);
-	if (err < 0)
-		DRM_ERROR("failed to disable link training: %d\n", err);
-}
-
-static int drm_dp_link_train_full(struct drm_dp_link *link)
-{
-	int err;
-
-retry:
-	DRM_DEBUG_KMS("full-training link: %u lane%s at %u MHz\n",
-		      link->lanes, (link->lanes > 1) ? "s" : "",
-		      link->rate / 100);
-
-	err = drm_dp_link_configure(link->aux, link);
-	if (err < 0) {
-		DRM_ERROR("failed to configure DP link: %d\n", err);
-		return err;
-	}
-
-	err = drm_dp_link_clock_recovery(link);
-	if (err < 0) {
-		DRM_ERROR("clock recovery failed: %d\n", err);
-		goto out;
-	}
-
-	if (!link->train.clock_recovered) {
-		DRM_ERROR("clock recovery failed, downgrading link\n");
-
-		err = drm_dp_link_downgrade(link);
-		if (err < 0)
-			goto out;
-
-		goto retry;
-	}
-
-	DRM_DEBUG_KMS("clock recovery succeeded\n");
-
-	err = drm_dp_link_channel_equalization(link);
-	if (err < 0) {
-		DRM_ERROR("channel equalization failed: %d\n", err);
-		goto out;
-	}
-
-	if (!link->train.channel_equalized) {
-		DRM_ERROR("channel equalization failed, downgrading link\n");
-
-		err = drm_dp_link_downgrade(link);
-		if (err < 0)
-			goto out;
-
-		goto retry;
-	}
-
-	DRM_DEBUG_KMS("channel equalization succeeded\n");
-
-out:
-	drm_dp_link_train_disable(link);
-	return err;
-}
-
-static int drm_dp_link_train_fast(struct drm_dp_link *link)
-{
-	u8 status[DP_LINK_STATUS_SIZE];
-	int err;
-
-	DRM_DEBUG_KMS("fast-training link: %u lane%s at %u MHz\n",
-		      link->lanes, (link->lanes > 1) ? "s" : "",
-		      link->rate / 100);
-
-	err = drm_dp_link_configure(link->aux, link);
-	if (err < 0) {
-		DRM_ERROR("failed to configure DP link: %d\n", err);
-		return err;
-	}
-
-	/* transmit training pattern 1 for 500 microseconds */
-	link->train.pattern = DP_TRAINING_PATTERN_1;
-
-	err = drm_dp_link_apply_training(link);
-	if (err < 0)
-		goto out;
-
-	usleep_range(500, 1000);
-
-	/* transmit training pattern 2 or 3 for 500 microseconds */
-	if (link->caps.tps3_supported)
-		link->train.pattern = DP_TRAINING_PATTERN_3;
-	else
-		link->train.pattern = DP_TRAINING_PATTERN_2;
-
-	err = drm_dp_link_apply_training(link);
-	if (err < 0)
-		goto out;
-
-	usleep_range(500, 1000);
-
-	err = drm_dp_dpcd_read_link_status(link->aux, status);
-	if (err < 0) {
-		DRM_ERROR("failed to read link status: %d\n", err);
-		goto out;
-	}
-
-	if (!drm_dp_clock_recovery_ok(status, link->lanes)) {
-		DRM_ERROR("clock recovery failed\n");
-		err = -EIO;
-	}
-
-	if (!drm_dp_channel_eq_ok(status, link->lanes)) {
-		DRM_ERROR("channel equalization failed\n");
-		err = -EIO;
-	}
-
-out:
-	drm_dp_link_train_disable(link);
-	return err;
-}
-
-/**
- * drm_dp_link_train() - perform DisplayPort link training
- * @link: a DP link object
- *
- * Uses the context stored in the DP link object to perform link training. It
- * is expected that drivers will call drm_dp_link_probe() to obtain the link
- * capabilities before performing link training.
- *
- * If the sink supports fast link training (no AUX CH handshake) and valid
- * training settings are available, this function will try to perform fast
- * link training and fall back to full link training on failure.
- *
- * Returns: 0 on success or a negative error code on failure.
- */
-int drm_dp_link_train(struct drm_dp_link *link)
-{
-	int err;
-
-	drm_dp_link_train_init(&link->train);
-
-	if (link->caps.fast_training) {
-		if (drm_dp_link_train_valid(&link->train)) {
-			err = drm_dp_link_train_fast(link);
-			if (err < 0)
-				DRM_ERROR("fast link training failed: %d\n",
-					  err);
-			else
-				return 0;
-		} else {
-			DRM_DEBUG_KMS("training parameters not available\n");
-		}
-	} else {
-		DRM_DEBUG_KMS("fast link training not supported\n");
-	}
-
-	err = drm_dp_link_train_full(link);
-	if (err < 0)
-		DRM_ERROR("full link training failed: %d\n", err);
-
-	return err;
-}
diff --git a/drivers/gpu/drm/tegra/dp.h b/drivers/gpu/drm/tegra/dp.h
deleted file mode 100644
index cb12ed0..00000000
--- a/drivers/gpu/drm/tegra/dp.h
+++ /dev/null
@@ -1,177 +0,0 @@
-/* SPDX-License-Identifier: MIT */
-/*
- * Copyright (C) 2013-2019 NVIDIA Corporation.
- * Copyright (C) 2015 Rob Clark
- */
-
-#ifndef DRM_TEGRA_DP_H
-#define DRM_TEGRA_DP_H 1
-
-#include <linux/types.h>
-
-struct drm_display_info;
-struct drm_display_mode;
-struct drm_dp_aux;
-struct drm_dp_link;
-
-/**
- * struct drm_dp_link_caps - DP link capabilities
- */
-struct drm_dp_link_caps {
-	/**
-	 * @enhanced_framing:
-	 *
-	 * enhanced framing capability (mandatory as of DP 1.2)
-	 */
-	bool enhanced_framing;
-
-	/**
-	 * tps3_supported:
-	 *
-	 * training pattern sequence 3 supported for equalization
-	 */
-	bool tps3_supported;
-
-	/**
-	 * @fast_training:
-	 *
-	 * AUX CH handshake not required for link training
-	 */
-	bool fast_training;
-
-	/**
-	 * @channel_coding:
-	 *
-	 * ANSI 8B/10B channel coding capability
-	 */
-	bool channel_coding;
-
-	/**
-	 * @alternate_scrambler_reset:
-	 *
-	 * eDP alternate scrambler reset capability
-	 */
-	bool alternate_scrambler_reset;
-};
-
-void drm_dp_link_caps_copy(struct drm_dp_link_caps *dest,
-			   const struct drm_dp_link_caps *src);
-
-/**
- * struct drm_dp_link_ops - DP link operations
- */
-struct drm_dp_link_ops {
-	/**
-	 * @apply_training:
-	 */
-	int (*apply_training)(struct drm_dp_link *link);
-
-	/**
-	 * @configure:
-	 */
-	int (*configure)(struct drm_dp_link *link);
-};
-
-#define DP_TRAIN_VOLTAGE_SWING_LEVEL(x) ((x) << 0)
-#define DP_TRAIN_PRE_EMPHASIS_LEVEL(x) ((x) << 3)
-#define DP_LANE_POST_CURSOR(i, x) (((x) & 0x3) << (((i) & 1) << 2))
-
-/**
- * struct drm_dp_link_train_set - link training settings
- * @voltage_swing: per-lane voltage swing
- * @pre_emphasis: per-lane pre-emphasis
- * @post_cursor: per-lane post-cursor
- */
-struct drm_dp_link_train_set {
-	unsigned int voltage_swing[4];
-	unsigned int pre_emphasis[4];
-	unsigned int post_cursor[4];
-};
-
-/**
- * struct drm_dp_link_train - link training state information
- * @request: currently requested settings
- * @adjust: adjustments requested by sink
- * @pattern: currently requested training pattern
- * @clock_recovered: flag to track if clock recovery has completed
- * @channel_equalized: flag to track if channel equalization has completed
- */
-struct drm_dp_link_train {
-	struct drm_dp_link_train_set request;
-	struct drm_dp_link_train_set adjust;
-
-	unsigned int pattern;
-
-	bool clock_recovered;
-	bool channel_equalized;
-};
-
-/**
- * struct drm_dp_link - DP link capabilities and configuration
- * @revision: DP specification revision supported on the link
- * @max_rate: maximum clock rate supported on the link
- * @max_lanes: maximum number of lanes supported on the link
- * @caps: capabilities supported on the link (see &drm_dp_link_caps)
- * @aux_rd_interval: AUX read interval to use for training (in microseconds)
- * @edp: eDP revision (0x11: eDP 1.1, 0x12: eDP 1.2, ...)
- * @rate: currently configured link rate
- * @lanes: currently configured number of lanes
- * @rates: additional supported link rates in kHz (eDP 1.4)
- * @num_rates: number of additional supported link rates (eDP 1.4)
- */
-struct drm_dp_link {
-	unsigned char revision;
-	unsigned int max_rate;
-	unsigned int max_lanes;
-
-	struct drm_dp_link_caps caps;
-
-	/**
-	 * @cr: clock recovery read interval
-	 * @ce: channel equalization read interval
-	 */
-	struct {
-		unsigned int cr;
-		unsigned int ce;
-	} aux_rd_interval;
-
-	unsigned char edp;
-
-	unsigned int rate;
-	unsigned int lanes;
-
-	unsigned long rates[DP_MAX_SUPPORTED_RATES];
-	unsigned int num_rates;
-
-	/**
-	 * @ops: DP link operations
-	 */
-	const struct drm_dp_link_ops *ops;
-
-	/**
-	 * @aux: DP AUX channel
-	 */
-	struct drm_dp_aux *aux;
-
-	/**
-	 * @train: DP link training state
-	 */
-	struct drm_dp_link_train train;
-};
-
-int drm_dp_link_add_rate(struct drm_dp_link *link, unsigned long rate);
-int drm_dp_link_remove_rate(struct drm_dp_link *link, unsigned long rate);
-void drm_dp_link_update_rates(struct drm_dp_link *link);
-
-int drm_dp_link_probe(struct drm_dp_aux *aux, struct drm_dp_link *link);
-int drm_dp_link_power_up(struct drm_dp_aux *aux, struct drm_dp_link *link);
-int drm_dp_link_power_down(struct drm_dp_aux *aux, struct drm_dp_link *link);
-int drm_dp_link_configure(struct drm_dp_aux *aux, struct drm_dp_link *link);
-int drm_dp_link_choose(struct drm_dp_link *link,
-		       const struct drm_display_mode *mode,
-		       const struct drm_display_info *info);
-
-void drm_dp_link_train_init(struct drm_dp_link_train *train);
-int drm_dp_link_train(struct drm_dp_link *link);
-
-#endif
diff --git a/drivers/gpu/drm/tegra/dpaux.c b/drivers/gpu/drm/tegra/dpaux.c
index 622cdf1..066177a 100644
--- a/drivers/gpu/drm/tegra/dpaux.c
+++ b/drivers/gpu/drm/tegra/dpaux.c
@@ -23,7 +23,6 @@
 #include <drm/drm_dp_helper.h>
 #include <drm/drm_panel.h>
 
-#include "dp.h"
 #include "dpaux.h"
 #include "drm.h"
 #include "trace.h"
diff --git a/drivers/gpu/drm/tegra/sor.c b/drivers/gpu/drm/tegra/sor.c
index 615cb31..29c3ae8 100644
--- a/drivers/gpu/drm/tegra/sor.c
+++ b/drivers/gpu/drm/tegra/sor.c
@@ -25,7 +25,6 @@
 #include <drm/drm_scdc_helper.h>
 
 #include "dc.h"
-#include "dp.h"
 #include "drm.h"
 #include "hda.h"
 #include "sor.h"
diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h
index 51ecb51..04f6c0b 100644
--- a/include/drm/drm_dp_helper.h
+++ b/include/drm/drm_dp_helper.h
@@ -1455,6 +1455,22 @@ static inline ssize_t drm_dp_dpcd_writeb(struct drm_dp_aux *aux,
 int drm_dp_dpcd_read_link_status(struct drm_dp_aux *aux,
 				 u8 status[DP_LINK_STATUS_SIZE]);
 
+/*
+ * DisplayPort link
+ */
+#define DP_LINK_CAP_ENHANCED_FRAMING (1 << 0)
+
+struct drm_dp_link {
+	unsigned char revision;
+	unsigned int rate;
+	unsigned int num_lanes;
+	unsigned long capabilities;
+};
+
+int drm_dp_link_probe(struct drm_dp_aux *aux, struct drm_dp_link *link);
+int drm_dp_link_power_up(struct drm_dp_aux *aux, struct drm_dp_link *link);
+int drm_dp_link_power_down(struct drm_dp_aux *aux, struct drm_dp_link *link);
+int drm_dp_link_configure(struct drm_dp_aux *aux, struct drm_dp_link *link);
 int drm_dp_downstream_max_clock(const u8 dpcd[DP_RECEIVER_CAP_SIZE],
 				const u8 port_cap[4]);
 int drm_dp_downstream_max_bpc(const u8 dpcd[DP_RECEIVER_CAP_SIZE],
-- 
1.9.1



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