Merge tag 'du-next-20191218' of git://linuxtv.org/pinchartl/media into drm-next

R-Car Display Unit changes:

- Color Management Module support
- LVDS encoder dual-link support enhancements
- R8A77980 support

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
From: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191218151710.GA13830@pendragon.ideasonboard.com

13 files changed, 643 insertions, 150 deletions

diff --git a/drivers/gpu/drm/rcar-du/Kconfig b/drivers/gpu/drm/rcar-du/Kconfig
index 1529849e217e..0919f1f159a4 100644
--- a/drivers/gpu/drm/rcar-du/Kconfig
+++ b/drivers/gpu/drm/rcar-du/Kconfig
@@ -4,6 +4,7 @@ config DRM_RCAR_DU
 	depends on DRM && OF
 	depends on ARM || ARM64
 	depends on ARCH_RENESAS || COMPILE_TEST
+	imply DRM_RCAR_CMM
 	imply DRM_RCAR_LVDS
 	select DRM_KMS_HELPER
 	select DRM_KMS_CMA_HELPER
@@ -13,6 +14,13 @@ config DRM_RCAR_DU
 	  Choose this option if you have an R-Car chipset.
 	  If M is selected the module will be called rcar-du-drm.
 
+config DRM_RCAR_CMM
+	tristate "R-Car DU Color Management Module (CMM) Support"
+	depends on DRM && OF
+	depends on DRM_RCAR_DU
+	help
+	  Enable support for R-Car Color Management Module (CMM).
+
 config DRM_RCAR_DW_HDMI
 	tristate "R-Car DU Gen3 HDMI Encoder Support"
 	depends on DRM && OF
diff --git a/drivers/gpu/drm/rcar-du/Makefile b/drivers/gpu/drm/rcar-du/Makefile
index 6c2ed9c46467..4d1187ccc3e5 100644
--- a/drivers/gpu/drm/rcar-du/Makefile
+++ b/drivers/gpu/drm/rcar-du/Makefile
@@ -15,6 +15,7 @@ rcar-du-drm-$(CONFIG_DRM_RCAR_LVDS)	+= rcar_du_of.o \
 rcar-du-drm-$(CONFIG_DRM_RCAR_VSP)	+= rcar_du_vsp.o
 rcar-du-drm-$(CONFIG_DRM_RCAR_WRITEBACK) += rcar_du_writeback.o
 
+obj-$(CONFIG_DRM_RCAR_CMM)		+= rcar_cmm.o
 obj-$(CONFIG_DRM_RCAR_DU)		+= rcar-du-drm.o
 obj-$(CONFIG_DRM_RCAR_DW_HDMI)		+= rcar_dw_hdmi.o
 obj-$(CONFIG_DRM_RCAR_LVDS)		+= rcar_lvds.o
diff --git a/drivers/gpu/drm/rcar-du/rcar_cmm.c b/drivers/gpu/drm/rcar-du/rcar_cmm.c
new file mode 100644
index 000000000000..c578095b09a5
--- /dev/null
+++ b/drivers/gpu/drm/rcar-du/rcar_cmm.c
@@ -0,0 +1,217 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * rcar_cmm.c -- R-Car Display Unit Color Management Module
+ *
+ * Copyright (C) 2019 Jacopo Mondi <jacopo+renesas@jmondi.org>
+ */
+
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+
+#include <drm/drm_color_mgmt.h>
+
+#include "rcar_cmm.h"
+
+#define CM2_LUT_CTRL		0x0000
+#define CM2_LUT_CTRL_LUT_EN	BIT(0)
+#define CM2_LUT_TBL_BASE	0x0600
+#define CM2_LUT_TBL(__i)	(CM2_LUT_TBL_BASE + (__i) * 4)
+
+struct rcar_cmm {
+	void __iomem *base;
+
+	/*
+	 * @lut:		1D-LUT state
+	 * @lut.enabled:	1D-LUT enabled flag
+	 */
+	struct {
+		bool enabled;
+	} lut;
+};
+
+static inline int rcar_cmm_read(struct rcar_cmm *rcmm, u32 reg)
+{
+	return ioread32(rcmm->base + reg);
+}
+
+static inline void rcar_cmm_write(struct rcar_cmm *rcmm, u32 reg, u32 data)
+{
+	iowrite32(data, rcmm->base + reg);
+}
+
+/*
+ * rcar_cmm_lut_write() - Scale the DRM LUT table entries to hardware precision
+ *			  and write to the CMM registers
+ * @rcmm: Pointer to the CMM device
+ * @drm_lut: Pointer to the DRM LUT table
+ */
+static void rcar_cmm_lut_write(struct rcar_cmm *rcmm,
+			       const struct drm_color_lut *drm_lut)
+{
+	unsigned int i;
+
+	for (i = 0; i < CM2_LUT_SIZE; ++i) {
+		u32 entry = drm_color_lut_extract(drm_lut[i].red, 8) << 16
+			  | drm_color_lut_extract(drm_lut[i].green, 8) << 8
+			  | drm_color_lut_extract(drm_lut[i].blue, 8);
+
+		rcar_cmm_write(rcmm, CM2_LUT_TBL(i), entry);
+	}
+}
+
+/*
+ * rcar_cmm_setup() - Configure the CMM unit
+ * @pdev: The platform device associated with the CMM instance
+ * @config: The CMM unit configuration
+ *
+ * Configure the CMM unit with the given configuration. Currently enabling,
+ * disabling and programming of the 1-D LUT unit is supported.
+ *
+ * As rcar_cmm_setup() accesses the CMM registers the unit should be powered
+ * and its functional clock enabled. To guarantee this, before any call to
+ * this function is made, the CMM unit has to be enabled by calling
+ * rcar_cmm_enable() first.
+ *
+ * TODO: Add support for LUT double buffer operations to avoid updating the
+ * LUT table entries while a frame is being displayed.
+ */
+int rcar_cmm_setup(struct platform_device *pdev,
+		   const struct rcar_cmm_config *config)
+{
+	struct rcar_cmm *rcmm = platform_get_drvdata(pdev);
+
+	/* Disable LUT if no table is provided. */
+	if (!config->lut.table) {
+		if (rcmm->lut.enabled) {
+			rcar_cmm_write(rcmm, CM2_LUT_CTRL, 0);
+			rcmm->lut.enabled = false;
+		}
+
+		return 0;
+	}
+
+	/* Enable LUT and program the new gamma table values. */
+	if (!rcmm->lut.enabled) {
+		rcar_cmm_write(rcmm, CM2_LUT_CTRL, CM2_LUT_CTRL_LUT_EN);
+		rcmm->lut.enabled = true;
+	}
+
+	rcar_cmm_lut_write(rcmm, config->lut.table);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(rcar_cmm_setup);
+
+/*
+ * rcar_cmm_enable() - Enable the CMM unit
+ * @pdev: The platform device associated with the CMM instance
+ *
+ * When the output of the corresponding DU channel is routed to the CMM unit,
+ * the unit shall be enabled before the DU channel is started, and remain
+ * enabled until the channel is stopped. The CMM unit shall be disabled with
+ * rcar_cmm_disable().
+ *
+ * Calls to rcar_cmm_enable() and rcar_cmm_disable() are not reference-counted.
+ * It is an error to attempt to enable an already enabled CMM unit, or to
+ * attempt to disable a disabled unit.
+ */
+int rcar_cmm_enable(struct platform_device *pdev)
+{
+	int ret;
+
+	ret = pm_runtime_get_sync(&pdev->dev);
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(rcar_cmm_enable);
+
+/*
+ * rcar_cmm_disable() - Disable the CMM unit
+ * @pdev: The platform device associated with the CMM instance
+ *
+ * See rcar_cmm_enable() for usage information.
+ *
+ * Disabling the CMM unit disable all the internal processing blocks. The CMM
+ * state shall thus be restored with rcar_cmm_setup() when re-enabling the CMM
+ * unit after the next rcar_cmm_enable() call.
+ */
+void rcar_cmm_disable(struct platform_device *pdev)
+{
+	struct rcar_cmm *rcmm = platform_get_drvdata(pdev);
+
+	rcar_cmm_write(rcmm, CM2_LUT_CTRL, 0);
+	rcmm->lut.enabled = false;
+
+	pm_runtime_put(&pdev->dev);
+}
+EXPORT_SYMBOL_GPL(rcar_cmm_disable);
+
+/*
+ * rcar_cmm_init() - Initialize the CMM unit
+ * @pdev: The platform device associated with the CMM instance
+ *
+ * Return: 0 on success, -EPROBE_DEFER if the CMM is not available yet,
+ *         -ENODEV if the DRM_RCAR_CMM config option is disabled
+ */
+int rcar_cmm_init(struct platform_device *pdev)
+{
+	struct rcar_cmm *rcmm = platform_get_drvdata(pdev);
+
+	if (!rcmm)
+		return -EPROBE_DEFER;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(rcar_cmm_init);
+
+static int rcar_cmm_probe(struct platform_device *pdev)
+{
+	struct rcar_cmm *rcmm;
+
+	rcmm = devm_kzalloc(&pdev->dev, sizeof(*rcmm), GFP_KERNEL);
+	if (!rcmm)
+		return -ENOMEM;
+	platform_set_drvdata(pdev, rcmm);
+
+	rcmm->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(rcmm->base))
+		return PTR_ERR(rcmm->base);
+
+	pm_runtime_enable(&pdev->dev);
+
+	return 0;
+}
+
+static int rcar_cmm_remove(struct platform_device *pdev)
+{
+	pm_runtime_disable(&pdev->dev);
+
+	return 0;
+}
+
+static const struct of_device_id rcar_cmm_of_table[] = {
+	{ .compatible = "renesas,rcar-gen3-cmm", },
+	{ .compatible = "renesas,rcar-gen2-cmm", },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, rcar_cmm_of_table);
+
+static struct platform_driver rcar_cmm_platform_driver = {
+	.probe		= rcar_cmm_probe,
+	.remove		= rcar_cmm_remove,
+	.driver		= {
+		.name	= "rcar-cmm",
+		.of_match_table = rcar_cmm_of_table,
+	},
+};
+
+module_platform_driver(rcar_cmm_platform_driver);
+
+MODULE_AUTHOR("Jacopo Mondi <jacopo+renesas@jmondi.org>");
+MODULE_DESCRIPTION("Renesas R-Car CMM Driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/gpu/drm/rcar-du/rcar_cmm.h b/drivers/gpu/drm/rcar-du/rcar_cmm.h
new file mode 100644
index 000000000000..b5f7ec6db04a
--- /dev/null
+++ b/drivers/gpu/drm/rcar-du/rcar_cmm.h
@@ -0,0 +1,58 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * rcar_cmm.h -- R-Car Display Unit Color Management Module
+ *
+ * Copyright (C) 2019 Jacopo Mondi <jacopo+renesas@jmondi.org>
+ */
+
+#ifndef __RCAR_CMM_H__
+#define __RCAR_CMM_H__
+
+#define CM2_LUT_SIZE		256
+
+struct drm_color_lut;
+struct platform_device;
+
+/**
+ * struct rcar_cmm_config - CMM configuration
+ *
+ * @lut:	1D-LUT configuration
+ * @lut.table:	1D-LUT table entries. Disable LUT operations when NULL
+ */
+struct rcar_cmm_config {
+	struct {
+		struct drm_color_lut *table;
+	} lut;
+};
+
+#if IS_ENABLED(CONFIG_DRM_RCAR_CMM)
+int rcar_cmm_init(struct platform_device *pdev);
+
+int rcar_cmm_enable(struct platform_device *pdev);
+void rcar_cmm_disable(struct platform_device *pdev);
+
+int rcar_cmm_setup(struct platform_device *pdev,
+		   const struct rcar_cmm_config *config);
+#else
+static inline int rcar_cmm_init(struct platform_device *pdev)
+{
+	return -ENODEV;
+}
+
+static inline int rcar_cmm_enable(struct platform_device *pdev)
+{
+	return 0;
+}
+
+static inline void rcar_cmm_disable(struct platform_device *pdev)
+{
+}
+
+static inline int rcar_cmm_setup(struct platform_device *pdev,
+				 const struct rcar_cmm_config *config)
+{
+	return 0;
+}
+#endif /* IS_ENABLED(CONFIG_DRM_RCAR_CMM) */
+
+#endif /* __RCAR_CMM_H__ */
diff --git a/drivers/gpu/drm/rcar-du/rcar_du_crtc.c b/drivers/gpu/drm/rcar-du/rcar_du_crtc.c
index f2ae4c410244..d73e88ddecd0 100644
--- a/drivers/gpu/drm/rcar-du/rcar_du_crtc.c
+++ b/drivers/gpu/drm/rcar-du/rcar_du_crtc.c
@@ -22,6 +22,7 @@
 #include <drm/drm_plane_helper.h>
 #include <drm/drm_vblank.h>
 
+#include "rcar_cmm.h"
 #include "rcar_du_crtc.h"
 #include "rcar_du_drv.h"
 #include "rcar_du_encoder.h"
@@ -476,6 +477,45 @@ static void rcar_du_crtc_wait_page_flip(struct rcar_du_crtc *rcrtc)
 }
 
 /* -----------------------------------------------------------------------------
+ * Color Management Module (CMM)
+ */
+
+static int rcar_du_cmm_check(struct drm_crtc *crtc,
+			     struct drm_crtc_state *state)
+{
+	struct drm_property_blob *drm_lut = state->gamma_lut;
+	struct rcar_du_crtc *rcrtc = to_rcar_crtc(crtc);
+	struct device *dev = rcrtc->dev->dev;
+
+	if (!drm_lut)
+		return 0;
+
+	/* We only accept fully populated LUT tables. */
+	if (drm_color_lut_size(drm_lut) != CM2_LUT_SIZE) {
+		dev_err(dev, "invalid gamma lut size: %zu bytes\n",
+			drm_lut->length);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static void rcar_du_cmm_setup(struct drm_crtc *crtc)
+{
+	struct drm_property_blob *drm_lut = crtc->state->gamma_lut;
+	struct rcar_du_crtc *rcrtc = to_rcar_crtc(crtc);
+	struct rcar_cmm_config cmm_config = {};
+
+	if (!rcrtc->cmm)
+		return;
+
+	if (drm_lut)
+		cmm_config.lut.table = (struct drm_color_lut *)drm_lut->data;
+
+	rcar_cmm_setup(rcrtc->cmm, &cmm_config);
+}
+
+/* -----------------------------------------------------------------------------
  * Start/Stop and Suspend/Resume
  */
 
@@ -620,6 +660,9 @@ static void rcar_du_crtc_stop(struct rcar_du_crtc *rcrtc)
 	if (rcar_du_has(rcrtc->dev, RCAR_DU_FEATURE_VSP1_SOURCE))
 		rcar_du_vsp_disable(rcrtc);
 
+	if (rcrtc->cmm)
+		rcar_cmm_disable(rcrtc->cmm);
+
 	/*
 	 * Select switch sync mode. This stops display operation and configures
 	 * the HSYNC and VSYNC signals as inputs.
@@ -643,6 +686,11 @@ static int rcar_du_crtc_atomic_check(struct drm_crtc *crtc,
 {
 	struct rcar_du_crtc_state *rstate = to_rcar_crtc_state(state);
 	struct drm_encoder *encoder;
+	int ret;
+
+	ret = rcar_du_cmm_check(crtc, state);
+	if (ret)
+		return ret;
 
 	/* Store the routes from the CRTC output to the DU outputs. */
 	rstate->outputs = 0;
@@ -668,6 +716,8 @@ static void rcar_du_crtc_atomic_enable(struct drm_crtc *crtc,
 	struct rcar_du_crtc_state *rstate = to_rcar_crtc_state(crtc->state);
 	struct rcar_du_device *rcdu = rcrtc->dev;
 
+	if (rcrtc->cmm)
+		rcar_cmm_enable(rcrtc->cmm);
 	rcar_du_crtc_get(rcrtc);
 
 	/*
@@ -688,6 +738,13 @@ static void rcar_du_crtc_atomic_enable(struct drm_crtc *crtc,
 	}
 
 	rcar_du_crtc_start(rcrtc);
+
+	/*
+	 * TODO: The chip manual indicates that CMM tables should be written
+	 * after the DU channel has been activated. Investigate the impact
+	 * of this restriction on the first displayed frame.
+	 */
+	rcar_du_cmm_setup(crtc);
 }
 
 static void rcar_du_crtc_atomic_disable(struct drm_crtc *crtc,
@@ -743,6 +800,10 @@ static void rcar_du_crtc_atomic_begin(struct drm_crtc *crtc,
 	 */
 	rcar_du_crtc_get(rcrtc);
 
+	/* If the active state changed, we let .atomic_enable handle CMM. */
+	if (crtc->state->color_mgmt_changed && !crtc->state->active_changed)
+		rcar_du_cmm_setup(crtc);
+
 	if (rcar_du_has(rcrtc->dev, RCAR_DU_FEATURE_VSP1_SOURCE))
 		rcar_du_vsp_atomic_begin(rcrtc);
 }
@@ -1079,6 +1140,7 @@ static const struct drm_crtc_funcs crtc_funcs_gen3 = {
 	.set_crc_source = rcar_du_crtc_set_crc_source,
 	.verify_crc_source = rcar_du_crtc_verify_crc_source,
 	.get_crc_sources = rcar_du_crtc_get_crc_sources,
+	.gamma_set = drm_atomic_helper_legacy_gamma_set,
 };
 
 /* -----------------------------------------------------------------------------
@@ -1198,6 +1260,15 @@ int rcar_du_crtc_create(struct rcar_du_group *rgrp, unsigned int swindex,
 	if (ret < 0)
 		return ret;
 
+	/* CMM might be disabled for this CRTC. */
+	if (rcdu->cmms[swindex]) {
+		rcrtc->cmm = rcdu->cmms[swindex];
+		rgrp->cmms_mask |= BIT(hwindex % 2);
+
+		drm_mode_crtc_set_gamma_size(crtc, CM2_LUT_SIZE);
+		drm_crtc_enable_color_mgmt(crtc, 0, false, CM2_LUT_SIZE);
+	}
+
 	drm_crtc_helper_add(crtc, &crtc_helper_funcs);
 
 	/* Start with vertical blanking interrupt reporting disabled. */
diff --git a/drivers/gpu/drm/rcar-du/rcar_du_crtc.h b/drivers/gpu/drm/rcar-du/rcar_du_crtc.h
index 3b7fc668996f..5f2940c42225 100644
--- a/drivers/gpu/drm/rcar-du/rcar_du_crtc.h
+++ b/drivers/gpu/drm/rcar-du/rcar_du_crtc.h
@@ -39,6 +39,7 @@ struct rcar_du_vsp;
  * @vblank_wait: wait queue used to signal vertical blanking
  * @vblank_count: number of vertical blanking interrupts to wait for
  * @group: CRTC group this CRTC belongs to
+ * @cmm: CMM associated with this CRTC
  * @vsp: VSP feeding video to this CRTC
  * @vsp_pipe: index of the VSP pipeline feeding video to this CRTC
  * @writeback: the writeback connector
@@ -64,6 +65,7 @@ struct rcar_du_crtc {
 	unsigned int vblank_count;
 
 	struct rcar_du_group *group;
+	struct platform_device *cmm;
 	struct rcar_du_vsp *vsp;
 	unsigned int vsp_pipe;
 
diff --git a/drivers/gpu/drm/rcar-du/rcar_du_drv.c b/drivers/gpu/drm/rcar-du/rcar_du_drv.c
index f266c17b907a..654e2dd08146 100644
--- a/drivers/gpu/drm/rcar-du/rcar_du_drv.c
+++ b/drivers/gpu/drm/rcar-du/rcar_du_drv.c
@@ -399,7 +399,10 @@ static const struct rcar_du_device_info rcar_du_r8a77970_info = {
 		  | RCAR_DU_FEATURE_TVM_SYNC,
 	.channels_mask = BIT(0),
 	.routes = {
-		/* R8A77970 has one RGB output and one LVDS output. */
+		/*
+		 * R8A77970 and R8A77980 have one RGB output and one LVDS
+		 * output.
+		 */
 		[RCAR_DU_OUTPUT_DPAD0] = {
 			.possible_crtcs = BIT(0),
 			.port = 0,
@@ -457,6 +460,7 @@ static const struct of_device_id rcar_du_of_table[] = {
 	{ .compatible = "renesas,du-r8a7796", .data = &rcar_du_r8a7796_info },
 	{ .compatible = "renesas,du-r8a77965", .data = &rcar_du_r8a77965_info },
 	{ .compatible = "renesas,du-r8a77970", .data = &rcar_du_r8a77970_info },
+	{ .compatible = "renesas,du-r8a77980", .data = &rcar_du_r8a77970_info },
 	{ .compatible = "renesas,du-r8a77990", .data = &rcar_du_r8a7799x_info },
 	{ .compatible = "renesas,du-r8a77995", .data = &rcar_du_r8a7799x_info },
 	{ }
diff --git a/drivers/gpu/drm/rcar-du/rcar_du_drv.h b/drivers/gpu/drm/rcar-du/rcar_du_drv.h
index 1327cd0df90a..61504c54e2ec 100644
--- a/drivers/gpu/drm/rcar-du/rcar_du_drv.h
+++ b/drivers/gpu/drm/rcar-du/rcar_du_drv.h
@@ -13,6 +13,7 @@
 #include <linux/kernel.h>
 #include <linux/wait.h>
 
+#include "rcar_cmm.h"
 #include "rcar_du_crtc.h"
 #include "rcar_du_group.h"
 #include "rcar_du_vsp.h"
@@ -85,6 +86,7 @@ struct rcar_du_device {
 	struct rcar_du_encoder *encoders[RCAR_DU_OUTPUT_MAX];
 
 	struct rcar_du_group groups[RCAR_DU_MAX_GROUPS];
+	struct platform_device *cmms[RCAR_DU_MAX_CRTCS];
 	struct rcar_du_vsp vsps[RCAR_DU_MAX_VSPS];
 
 	struct {
diff --git a/drivers/gpu/drm/rcar-du/rcar_du_group.c b/drivers/gpu/drm/rcar-du/rcar_du_group.c
index 9eee47969e77..88a783ceb3e9 100644
--- a/drivers/gpu/drm/rcar-du/rcar_du_group.c
+++ b/drivers/gpu/drm/rcar-du/rcar_du_group.c
@@ -135,6 +135,7 @@ static void rcar_du_group_setup_didsr(struct rcar_du_group *rgrp)
 static void rcar_du_group_setup(struct rcar_du_group *rgrp)
 {
 	struct rcar_du_device *rcdu = rgrp->dev;
+	u32 defr7 = DEFR7_CODE;
 
 	/* Enable extended features */
 	rcar_du_group_write(rgrp, DEFR, DEFR_CODE | DEFR_DEFE);
@@ -147,6 +148,15 @@ static void rcar_du_group_setup(struct rcar_du_group *rgrp)
 
 	rcar_du_group_setup_pins(rgrp);
 
+	/*
+	 * TODO: Handle routing of the DU output to CMM dynamically, as we
+	 * should bypass CMM completely when no color management feature is
+	 * used.
+	 */
+	defr7 |= (rgrp->cmms_mask & BIT(1) ? DEFR7_CMME1 : 0) |
+		 (rgrp->cmms_mask & BIT(0) ? DEFR7_CMME0 : 0);
+	rcar_du_group_write(rgrp, DEFR7, defr7);
+
 	if (rcdu->info->gen >= 2) {
 		rcar_du_group_setup_defr8(rgrp);
 		rcar_du_group_setup_didsr(rgrp);
diff --git a/drivers/gpu/drm/rcar-du/rcar_du_group.h b/drivers/gpu/drm/rcar-du/rcar_du_group.h
index 87950c1f6a52..e9906609c635 100644
--- a/drivers/gpu/drm/rcar-du/rcar_du_group.h
+++ b/drivers/gpu/drm/rcar-du/rcar_du_group.h
@@ -22,6 +22,7 @@ struct rcar_du_device;
  * @mmio_offset: registers offset in the device memory map
  * @index: group index
  * @channels_mask: bitmask of populated DU channels in this group
+ * @cmms_mask: bitmask of available CMMs in this group
  * @num_crtcs: number of CRTCs in this group (1 or 2)
  * @use_count: number of users of the group (rcar_du_group_(get|put))
  * @used_crtcs: number of CRTCs currently in use
@@ -37,6 +38,7 @@ struct rcar_du_group {
 	unsigned int index;
 
 	unsigned int channels_mask;
+	unsigned int cmms_mask;
 	unsigned int num_crtcs;
 	unsigned int use_count;
 	unsigned int used_crtcs;
diff --git a/drivers/gpu/drm/rcar-du/rcar_du_kms.c b/drivers/gpu/drm/rcar-du/rcar_du_kms.c
index 0d59f390de19..fcfd916227d1 100644
--- a/drivers/gpu/drm/rcar-du/rcar_du_kms.c
+++ b/drivers/gpu/drm/rcar-du/rcar_du_kms.c
@@ -17,7 +17,9 @@
 #include <drm/drm_probe_helper.h>
 #include <drm/drm_vblank.h>
 
+#include <linux/device.h>
 #include <linux/of_graph.h>
+#include <linux/of_platform.h>
 #include <linux/wait.h>
 
 #include "rcar_du_crtc.h"
@@ -542,6 +544,7 @@ static int rcar_du_properties_init(struct rcar_du_device *rcdu)
 static int rcar_du_vsps_init(struct rcar_du_device *rcdu)
 {
 	const struct device_node *np = rcdu->dev->of_node;
+	const char *vsps_prop_name = "renesas,vsps";
 	struct of_phandle_args args;
 	struct {
 		struct device_node *np;
@@ -557,15 +560,21 @@ static int rcar_du_vsps_init(struct rcar_du_device *rcdu)
 	 * entry contains a pointer to the VSP DT node and a bitmask of the
 	 * connected DU CRTCs.
 	 */
-	cells = of_property_count_u32_elems(np, "vsps") / rcdu->num_crtcs - 1;
+	ret = of_property_count_u32_elems(np, vsps_prop_name);
+	if (ret < 0) {
+		/* Backward compatibility with old DTBs. */
+		vsps_prop_name = "vsps";
+		ret = of_property_count_u32_elems(np, vsps_prop_name);
+	}
+	cells = ret / rcdu->num_crtcs - 1;
 	if (cells > 1)
 		return -EINVAL;
 
 	for (i = 0; i < rcdu->num_crtcs; ++i) {
 		unsigned int j;
 
-		ret = of_parse_phandle_with_fixed_args(np, "vsps", cells, i,
-						       &args);
+		ret = of_parse_phandle_with_fixed_args(np, vsps_prop_name,
+						       cells, i, &args);
 		if (ret < 0)
 			goto error;
 
@@ -587,8 +596,8 @@ static int rcar_du_vsps_init(struct rcar_du_device *rcdu)
 
 		/*
 		 * Store the VSP pointer and pipe index in the CRTC. If the
-		 * second cell of the 'vsps' specifier isn't present, default
-		 * to 0 to remain compatible with older DT bindings.
+		 * second cell of the 'renesas,vsps' specifier isn't present,
+		 * default to 0 to remain compatible with older DT bindings.
 		 */
 		rcdu->crtcs[i].vsp = &rcdu->vsps[j];
 		rcdu->crtcs[i].vsp_pipe = cells >= 1 ? args.args[0] : 0;
@@ -618,6 +627,75 @@ error:
 	return ret;
 }
 
+static int rcar_du_cmm_init(struct rcar_du_device *rcdu)
+{
+	const struct device_node *np = rcdu->dev->of_node;
+	unsigned int i;
+	int cells;
+
+	cells = of_property_count_u32_elems(np, "renesas,cmms");
+	if (cells == -EINVAL)
+		return 0;
+
+	if (cells > rcdu->num_crtcs) {
+		dev_err(rcdu->dev,
+			"Invalid number of entries in 'renesas,cmms'\n");
+		return -EINVAL;
+	}
+
+	for (i = 0; i < cells; ++i) {
+		struct platform_device *pdev;
+		struct device_link *link;
+		struct device_node *cmm;
+		int ret;
+
+		cmm = of_parse_phandle(np, "renesas,cmms", i);
+		if (IS_ERR(cmm)) {
+			dev_err(rcdu->dev,
+				"Failed to parse 'renesas,cmms' property\n");
+			return PTR_ERR(cmm);
+		}
+
+		if (!of_device_is_available(cmm)) {
+			/* It's fine to have a phandle to a non-enabled CMM. */
+			of_node_put(cmm);
+			continue;
+		}
+
+		pdev = of_find_device_by_node(cmm);
+		if (IS_ERR(pdev)) {
+			dev_err(rcdu->dev, "No device found for CMM%u\n", i);
+			of_node_put(cmm);
+			return PTR_ERR(pdev);
+		}
+
+		of_node_put(cmm);
+
+		/*
+		 * -ENODEV is used to report that the CMM config option is
+		 * disabled: return 0 and let the DU continue probing.
+		 */
+		ret = rcar_cmm_init(pdev);
+		if (ret)
+			return ret == -ENODEV ? 0 : ret;
+
+		/*
+		 * Enforce suspend/resume ordering by making the CMM a provider
+		 * of the DU: CMM is suspended after and resumed before the DU.
+		 */
+		link = device_link_add(rcdu->dev, &pdev->dev, DL_FLAG_STATELESS);
+		if (!link) {
+			dev_err(rcdu->dev,
+				"Failed to create device link to CMM%u\n", i);
+			return -EINVAL;
+		}
+
+		rcdu->cmms[i] = pdev;
+	}
+
+	return 0;
+}
+
 int rcar_du_modeset_init(struct rcar_du_device *rcdu)
 {
 	static const unsigned int mmio_offsets[] = {
@@ -708,6 +786,11 @@ int rcar_du_modeset_init(struct rcar_du_device *rcdu)
 			return ret;
 	}
 
+	/* Initialize the Color Management Modules. */
+	ret = rcar_du_cmm_init(rcdu);
+	if (ret)
+		return ret;
+
 	/* Create the CRTCs. */
 	for (swindex = 0, hwindex = 0; swindex < rcdu->num_crtcs; ++hwindex) {
 		struct rcar_du_group *rgrp;
diff --git a/drivers/gpu/drm/rcar-du/rcar_du_regs.h b/drivers/gpu/drm/rcar-du/rcar_du_regs.h
index bc87f080b170..fb9964949368 100644
--- a/drivers/gpu/drm/rcar-du/rcar_du_regs.h
+++ b/drivers/gpu/drm/rcar-du/rcar_du_regs.h
@@ -197,6 +197,11 @@
 #define DEFR6_MLOS1		(1 << 2)
 #define DEFR6_DEFAULT		(DEFR6_CODE | DEFR6_TCNE1)
 
+#define DEFR7			0x000ec
+#define DEFR7_CODE		(0x7779 << 16)
+#define DEFR7_CMME1		BIT(6)
+#define DEFR7_CMME0		BIT(4)
+
 /* -----------------------------------------------------------------------------
  * R8A7790-only Control Registers
  */
diff --git a/drivers/gpu/drm/rcar-du/rcar_lvds.c b/drivers/gpu/drm/rcar-du/rcar_lvds.c
index 2cf44b91853c..8ffa4fbbdeb3 100644
--- a/drivers/gpu/drm/rcar-du/rcar_lvds.c
+++ b/drivers/gpu/drm/rcar-du/rcar_lvds.c
@@ -21,6 +21,7 @@
 #include <drm/drm_atomic.h>
 #include <drm/drm_atomic_helper.h>
 #include <drm/drm_bridge.h>
+#include <drm/drm_of.h>
 #include <drm/drm_panel.h>
 #include <drm/drm_probe_helper.h>
 
@@ -36,6 +37,12 @@ enum rcar_lvds_mode {
 	RCAR_LVDS_MODE_VESA = 4,
 };
 
+enum rcar_lvds_link_type {
+	RCAR_LVDS_SINGLE_LINK = 0,
+	RCAR_LVDS_DUAL_LINK_EVEN_ODD_PIXELS = 1,
+	RCAR_LVDS_DUAL_LINK_ODD_EVEN_PIXELS = 2,
+};
+
 #define RCAR_LVDS_QUIRK_LANES		BIT(0)	/* LVDS lanes 1 and 3 inverted */
 #define RCAR_LVDS_QUIRK_GEN3_LVEN	BIT(1)	/* LVEN bit needs to be set on R8A77970/R8A7799x */
 #define RCAR_LVDS_QUIRK_PWD		BIT(2)	/* PWD bit available (all of Gen3 but E3) */
@@ -65,11 +72,8 @@ struct rcar_lvds {
 		struct clk *dotclkin[2];	/* External DU clocks */
 	} clocks;
 
-	struct drm_display_mode display_mode;
-	enum rcar_lvds_mode mode;
-
 	struct drm_bridge *companion;
-	bool dual_link;
+	enum rcar_lvds_link_type link_type;
 };
 
 #define bridge_to_rcar_lvds(b) \
@@ -402,10 +406,53 @@ EXPORT_SYMBOL_GPL(rcar_lvds_clk_disable);
  * Bridge
  */
 
-static void rcar_lvds_enable(struct drm_bridge *bridge)
+static enum rcar_lvds_mode rcar_lvds_get_lvds_mode(struct rcar_lvds *lvds,
+					const struct drm_connector *connector)
+{
+	const struct drm_display_info *info;
+	enum rcar_lvds_mode mode;
+
+	/*
+	 * There is no API yet to retrieve LVDS mode from a bridge, only panels
+	 * are supported.
+	 */
+	if (!lvds->panel)
+		return RCAR_LVDS_MODE_JEIDA;
+
+	info = &connector->display_info;
+	if (!info->num_bus_formats || !info->bus_formats) {
+		dev_warn(lvds->dev,
+			 "no LVDS bus format reported, using JEIDA\n");
+		return RCAR_LVDS_MODE_JEIDA;
+	}
+
+	switch (info->bus_formats[0]) {
+	case MEDIA_BUS_FMT_RGB666_1X7X3_SPWG:
+	case MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA:
+		mode = RCAR_LVDS_MODE_JEIDA;
+		break;
+	case MEDIA_BUS_FMT_RGB888_1X7X4_SPWG:
+		mode = RCAR_LVDS_MODE_VESA;
+		break;
+	default:
+		dev_warn(lvds->dev,
+			 "unsupported LVDS bus format 0x%04x, using JEIDA\n",
+			 info->bus_formats[0]);
+		return RCAR_LVDS_MODE_JEIDA;
+	}
+
+	if (info->bus_flags & DRM_BUS_FLAG_DATA_LSB_TO_MSB)
+		mode |= RCAR_LVDS_MODE_MIRROR;
+
+	return mode;
+}
+
+static void __rcar_lvds_atomic_enable(struct drm_bridge *bridge,
+				      struct drm_atomic_state *state,
+				      struct drm_crtc *crtc,
+				      struct drm_connector *connector)
 {
 	struct rcar_lvds *lvds = bridge_to_rcar_lvds(bridge);
-	const struct drm_display_mode *mode = &lvds->display_mode;
 	u32 lvdhcr;
 	u32 lvdcr0;
 	int ret;
@@ -415,8 +462,9 @@ static void rcar_lvds_enable(struct drm_bridge *bridge)
 		return;
 
 	/* Enable the companion LVDS encoder in dual-link mode. */
-	if (lvds->dual_link && lvds->companion)
-		lvds->companion->funcs->enable(lvds->companion);
+	if (lvds->link_type != RCAR_LVDS_SINGLE_LINK && lvds->companion)
+		__rcar_lvds_atomic_enable(lvds->companion, state, crtc,
+					  connector);
 
 	/*
 	 * Hardcode the channels and control signals routing for now.
@@ -440,30 +488,51 @@ static void rcar_lvds_enable(struct drm_bridge *bridge)
 	rcar_lvds_write(lvds, LVDCHCR, lvdhcr);
 
 	if (lvds->info->quirks & RCAR_LVDS_QUIRK_DUAL_LINK) {
-		/*
-		 * Configure vertical stripe based on the mode of operation of
-		 * the connected device.
-		 */
-		rcar_lvds_write(lvds, LVDSTRIPE,
-				lvds->dual_link ? LVDSTRIPE_ST_ON : 0);
+		u32 lvdstripe = 0;
+
+		if (lvds->link_type != RCAR_LVDS_SINGLE_LINK) {
+			/*
+			 * By default we generate even pixels from the primary
+			 * encoder and odd pixels from the companion encoder.
+			 * Swap pixels around if the sink requires odd pixels
+			 * from the primary encoder and even pixels from the
+			 * companion encoder.
+			 */
+			bool swap_pixels = lvds->link_type ==
+				RCAR_LVDS_DUAL_LINK_ODD_EVEN_PIXELS;
+
+			/*
+			 * Configure vertical stripe since we are dealing with
+			 * an LVDS dual-link connection.
+			 *
+			 * ST_SWAP is reserved for the companion encoder, only
+			 * set it in the primary encoder.
+			 */
+			lvdstripe = LVDSTRIPE_ST_ON
+				  | (lvds->companion && swap_pixels ?
+				     LVDSTRIPE_ST_SWAP : 0);
+		}
+		rcar_lvds_write(lvds, LVDSTRIPE, lvdstripe);
 	}
 
 	/*
 	 * PLL clock configuration on all instances but the companion in
 	 * dual-link mode.
 	 */
-	if (!lvds->dual_link || lvds->companion)
+	if (lvds->link_type == RCAR_LVDS_SINGLE_LINK || lvds->companion) {
+		const struct drm_crtc_state *crtc_state =
+			drm_atomic_get_new_crtc_state(state, crtc);
+		const struct drm_display_mode *mode =
+			&crtc_state->adjusted_mode;
+
 		lvds->info->pll_setup(lvds, mode->clock * 1000);
+	}
 
 	/* Set the LVDS mode and select the input. */
-	lvdcr0 = lvds->mode << LVDCR0_LVMD_SHIFT;
+	lvdcr0 = rcar_lvds_get_lvds_mode(lvds, connector) << LVDCR0_LVMD_SHIFT;
 
 	if (lvds->bridge.encoder) {
-		/*
-		 * FIXME: We should really retrieve the CRTC through the state,
-		 * but how do we get a state pointer?
-		 */
-		if (drm_crtc_index(lvds->bridge.encoder->crtc) == 2)
+		if (drm_crtc_index(crtc) == 2)
 			lvdcr0 |= LVDCR0_DUSEL;
 	}
 
@@ -520,7 +589,21 @@ static void rcar_lvds_enable(struct drm_bridge *bridge)
 	}
 }
 
-static void rcar_lvds_disable(struct drm_bridge *bridge)
+static void rcar_lvds_atomic_enable(struct drm_bridge *bridge,
+				    struct drm_atomic_state *state)
+{
+	struct drm_connector *connector;
+	struct drm_crtc *crtc;
+
+	connector = drm_atomic_get_new_connector_for_encoder(state,
+							     bridge->encoder);
+	crtc = drm_atomic_get_new_connector_state(state, connector)->crtc;
+
+	__rcar_lvds_atomic_enable(bridge, state, crtc, connector);
+}
+
+static void rcar_lvds_atomic_disable(struct drm_bridge *bridge,
+				     struct drm_atomic_state *state)
 {
 	struct rcar_lvds *lvds = bridge_to_rcar_lvds(bridge);
 
@@ -534,8 +617,8 @@ static void rcar_lvds_disable(struct drm_bridge *bridge)
 	rcar_lvds_write(lvds, LVDPLLCR, 0);
 
 	/* Disable the companion LVDS encoder in dual-link mode. */
-	if (lvds->dual_link && lvds->companion)
-		lvds->companion->funcs->disable(lvds->companion);
+	if (lvds->link_type != RCAR_LVDS_SINGLE_LINK && lvds->companion)
+		lvds->companion->funcs->atomic_disable(lvds->companion, state);
 
 	clk_disable_unprepare(lvds->clocks.mod);
 }
@@ -558,54 +641,6 @@ static bool rcar_lvds_mode_fixup(struct drm_bridge *bridge,
 	return true;
 }
 
-static void rcar_lvds_get_lvds_mode(struct rcar_lvds *lvds)
-{
-	struct drm_display_info *info = &lvds->connector.display_info;
-	enum rcar_lvds_mode mode;
-
-	/*
-	 * There is no API yet to retrieve LVDS mode from a bridge, only panels
-	 * are supported.
-	 */
-	if (!lvds->panel)
-		return;
-
-	if (!info->num_bus_formats || !info->bus_formats) {
-		dev_err(lvds->dev, "no LVDS bus format reported\n");
-		return;
-	}
-
-	switch (info->bus_formats[0]) {
-	case MEDIA_BUS_FMT_RGB666_1X7X3_SPWG:
-	case MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA:
-		mode = RCAR_LVDS_MODE_JEIDA;
-		break;
-	case MEDIA_BUS_FMT_RGB888_1X7X4_SPWG:
-		mode = RCAR_LVDS_MODE_VESA;
-		break;
-	default:
-		dev_err(lvds->dev, "unsupported LVDS bus format 0x%04x\n",
-			info->bus_formats[0]);
-		return;
-	}
-
-	if (info->bus_flags & DRM_BUS_FLAG_DATA_LSB_TO_MSB)
-		mode |= RCAR_LVDS_MODE_MIRROR;
-
-	lvds->mode = mode;
-}
-
-static void rcar_lvds_mode_set(struct drm_bridge *bridge,
-			       const struct drm_display_mode *mode,
-			       const struct drm_display_mode *adjusted_mode)
-{
-	struct rcar_lvds *lvds = bridge_to_rcar_lvds(bridge);
-
-	lvds->display_mode = *adjusted_mode;
-
-	rcar_lvds_get_lvds_mode(lvds);
-}
-
 static int rcar_lvds_attach(struct drm_bridge *bridge)
 {
 	struct rcar_lvds *lvds = bridge_to_rcar_lvds(bridge);
@@ -647,17 +682,16 @@ static void rcar_lvds_detach(struct drm_bridge *bridge)
 static const struct drm_bridge_funcs rcar_lvds_bridge_ops = {
 	.attach = rcar_lvds_attach,
 	.detach = rcar_lvds_detach,
-	.enable = rcar_lvds_enable,
-	.disable = rcar_lvds_disable,
+	.atomic_enable = rcar_lvds_atomic_enable,
+	.atomic_disable = rcar_lvds_atomic_disable,
 	.mode_fixup = rcar_lvds_mode_fixup,
-	.mode_set = rcar_lvds_mode_set,
 };
 
 bool rcar_lvds_dual_link(struct drm_bridge *bridge)
 {
 	struct rcar_lvds *lvds = bridge_to_rcar_lvds(bridge);
 
-	return lvds->dual_link;
+	return lvds->link_type != RCAR_LVDS_SINGLE_LINK;
 }
 EXPORT_SYMBOL_GPL(rcar_lvds_dual_link);
 
@@ -669,7 +703,10 @@ static int rcar_lvds_parse_dt_companion(struct rcar_lvds *lvds)
 {
 	const struct of_device_id *match;
 	struct device_node *companion;
+	struct device_node *port0, *port1;
+	struct rcar_lvds *companion_lvds;
 	struct device *dev = lvds->dev;
+	int dual_link;
 	int ret = 0;
 
 	/* Locate the companion LVDS encoder for dual-link operation, if any. */
@@ -688,13 +725,68 @@ static int rcar_lvds_parse_dt_companion(struct rcar_lvds *lvds)
 		goto done;
 	}
 
+	/*
+	 * We need to work out if the sink is expecting us to function in
+	 * dual-link mode. We do this by looking at the DT port nodes we are
+	 * connected to, if they are marked as expecting even pixels and
+	 * odd pixels than we need to enable vertical stripe output.
+	 */
+	port0 = of_graph_get_port_by_id(dev->of_node, 1);
+	port1 = of_graph_get_port_by_id(companion, 1);
+	dual_link = drm_of_lvds_get_dual_link_pixel_order(port0, port1);
+	of_node_put(port0);
+	of_node_put(port1);
+
+	switch (dual_link) {
+	case DRM_LVDS_DUAL_LINK_ODD_EVEN_PIXELS:
+		lvds->link_type = RCAR_LVDS_DUAL_LINK_ODD_EVEN_PIXELS;
+		break;
+	case DRM_LVDS_DUAL_LINK_EVEN_ODD_PIXELS:
+		lvds->link_type = RCAR_LVDS_DUAL_LINK_EVEN_ODD_PIXELS;
+		break;
+	default:
+		/*
+		 * Early dual-link bridge specific implementations populate the
+		 * timings field of drm_bridge. If the flag is set, we assume
+		 * that we are expected to generate even pixels from the primary
+		 * encoder, and odd pixels from the companion encoder.
+		 */
+		if (lvds->next_bridge && lvds->next_bridge->timings &&
+		    lvds->next_bridge->timings->dual_link)
+			lvds->link_type = RCAR_LVDS_DUAL_LINK_EVEN_ODD_PIXELS;
+		else
+			lvds->link_type = RCAR_LVDS_SINGLE_LINK;
+	}
+
+	if (lvds->link_type == RCAR_LVDS_SINGLE_LINK) {
+		dev_dbg(dev, "Single-link configuration detected\n");
+		goto done;
+	}
+
 	lvds->companion = of_drm_find_bridge(companion);
 	if (!lvds->companion) {
 		ret = -EPROBE_DEFER;
 		goto done;
 	}
 
-	dev_dbg(dev, "Found companion encoder %pOF\n", companion);
+	dev_dbg(dev,
+		"Dual-link configuration detected (companion encoder %pOF)\n",
+		companion);
+
+	if (lvds->link_type == RCAR_LVDS_DUAL_LINK_ODD_EVEN_PIXELS)
+		dev_dbg(dev, "Data swapping required\n");
+
+	/*
+	 * FIXME: We should not be messing with the companion encoder private
+	 * data from the primary encoder, we should rather let the companion
+	 * encoder work things out on its own. However, the companion encoder
+	 * doesn't hold a reference to the primary encoder, and
+	 * drm_of_lvds_get_dual_link_pixel_order needs to be given references
+	 * to the output ports of both encoders, therefore leave it like this
+	 * for the time being.
+	 */
+	companion_lvds = bridge_to_rcar_lvds(lvds->companion);
+	companion_lvds->link_type = lvds->link_type;
 
 done:
 	of_node_put(companion);
@@ -704,79 +796,17 @@ done:
 
 static int rcar_lvds_parse_dt(struct rcar_lvds *lvds)
 {
-	struct device_node *local_output = NULL;
-	struct device_node *remote_input = NULL;
-	struct device_node *remote = NULL;
-	struct device_node *node;
-	bool is_bridge = false;
-	int ret = 0;
-
-	local_output = of_graph_get_endpoint_by_regs(lvds->dev->of_node, 1, 0);
-	if (!local_output) {
-		dev_dbg(lvds->dev, "unconnected port@1\n");
-		ret = -ENODEV;
-		goto done;
-	}
-
-	/*
-	 * Locate the connected entity and infer its type from the number of
-	 * endpoints.
-	 */
-	remote = of_graph_get_remote_port_parent(local_output);
-	if (!remote) {
-		dev_dbg(lvds->dev, "unconnected endpoint %pOF\n", local_output);
-		ret = -ENODEV;
-		goto done;
-	}
+	int ret;
 
-	if (!of_device_is_available(remote)) {
-		dev_dbg(lvds->dev, "connected entity %pOF is disabled\n",
-			remote);
-		ret = -ENODEV;
+	ret = drm_of_find_panel_or_bridge(lvds->dev->of_node, 1, 0,
+					  &lvds->panel, &lvds->next_bridge);
+	if (ret)
 		goto done;
-	}
-
-	remote_input = of_graph_get_remote_endpoint(local_output);
 
-	for_each_endpoint_of_node(remote, node) {
-		if (node != remote_input) {
-			/*
-			 * We've found one endpoint other than the input, this
-			 * must be a bridge.
-			 */
-			is_bridge = true;
-			of_node_put(node);
-			break;
-		}
-	}
-
-	if (is_bridge) {
-		lvds->next_bridge = of_drm_find_bridge(remote);
-		if (!lvds->next_bridge) {
-			ret = -EPROBE_DEFER;
-			goto done;
-		}
-
-		if (lvds->info->quirks & RCAR_LVDS_QUIRK_DUAL_LINK)
-			lvds->dual_link = lvds->next_bridge->timings
-					? lvds->next_bridge->timings->dual_link
-					: false;
-	} else {
-		lvds->panel = of_drm_find_panel(remote);
-		if (IS_ERR(lvds->panel)) {
-			ret = PTR_ERR(lvds->panel);
-			goto done;
-		}
-	}
-
-	if (lvds->dual_link)
+	if (lvds->info->quirks & RCAR_LVDS_QUIRK_DUAL_LINK)
 		ret = rcar_lvds_parse_dt_companion(lvds);
 
 done:
-	of_node_put(local_output);
-	of_node_put(remote_input);
-	of_node_put(remote);
-
 	/*
 	 * On D3/E3 the LVDS encoder provides a clock to the DU, which can be
 	 * used for the DPAD output even when the LVDS output is not connected.