[PATCH v2 0/6] drm: lcdif: Add i.MX93 LCDIF support

[PATCH v2 0/6] drm: lcdif: Add i.MX93 LCDIF support

[Liu Ying]

Hi,

This patch set aims to add i.MX93 LCDIF display controller support
in the existing LCDIF DRM driver.  The LCDIF embedded in i.MX93 SoC
is essentially the same to those embedded in i.MX8mp SoC.  Through
internal bridges, i.MX93 LCDIF may drive a MIPI DSI display or a LVDS
display or a parallel display.

Patch 1/6 adds device tree binding support for i.MX93 LCDIF in the
existing fsl,lcdif.yaml.

Patch 2/6 drops lcdif->bridge NULL pointer check as a cleanup patch.

Patch 3/6~5/6 prepare for adding i.MX93 LCDIF support step by step.

Patch 6/6 adds i.MX93 LCDIF compatible string as the last step of
adding i.MX93 LCDIF support.

v1->v2:
* Add Krzysztof's A-b and Marek's R-b tags on patch 1/6.
* Split patch 2/2 in v1 into patch 2/6~6/6 in v2. (Marek, Alexander)
* Drop '!remote ||' from lcdif_attach_bridge(). (Lothar)
* Add comment on the 'base' member of lcdif_crtc_state structure to
  note it should always be the first member. (Lothar)
* Drop unneeded 'bridges' member from lcdif_drm_private structure.
* Drop a comment about bridge input bus format from lcdif_crtc_atomic_check().

Liu Ying (6):
  dt-bindings: lcdif: Add i.MX93 LCDIF support
  drm: lcdif: Drop unnecessary NULL pointer check on lcdif->bridge
  drm: lcdif: Determine bus format and flags in ->atomic_check()
  drm: lcdif: Check consistent bus format and flags across first bridges
  drm: lcdif: Add multiple encoders and first bridges support
  drm: lcdif: Add i.MX93 LCDIF compatible string

 .../bindings/display/fsl,lcdif.yaml           |   7 +-
 drivers/gpu/drm/mxsfb/lcdif_drv.c             |  71 +++++-
 drivers/gpu/drm/mxsfb/lcdif_drv.h             |   5 +-
 drivers/gpu/drm/mxsfb/lcdif_kms.c             | 202 ++++++++++++------
 4 files changed, 207 insertions(+), 78 deletions(-)

-- 
2.37.1

[PATCH v2 1/6] dt-bindings: lcdif: Add i.MX93 LCDIF support

[Liu Ying]

There is one LCDIF embedded in i.MX93 SoC to connect with
MIPI DSI controller through LCDIF cross line pattern(controlled
by mediamix blk-ctrl) or connect with LVDS display bridge(LDB)
directly or connect with a parallel display through parallel
display format(also controlled by mediamix blk-ctrl).  i.MX93
LCDIF IP is essentially the same to i.MX8MP LCDIF IP.  Add device
tree binding for i.MX93 LCDIF.

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Marek Vasut <marex@denx.de>
Signed-off-by: Liu Ying <victor.liu@nxp.com>
---
v1->v2:
* Add Krzysztof's A-b and Marek's R-b tags on patch 1/6.

 Documentation/devicetree/bindings/display/fsl,lcdif.yaml | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/display/fsl,lcdif.yaml b/Documentation/devicetree/bindings/display/fsl,lcdif.yaml
index 75b4efd70ba8..fc11ab5fc465 100644
--- a/Documentation/devicetree/bindings/display/fsl,lcdif.yaml
+++ b/Documentation/devicetree/bindings/display/fsl,lcdif.yaml
@@ -21,6 +21,7 @@ properties:
           - fsl,imx28-lcdif
           - fsl,imx6sx-lcdif
           - fsl,imx8mp-lcdif
+          - fsl,imx93-lcdif
       - items:
           - enum:
               - fsl,imx6sl-lcdif
@@ -88,7 +89,9 @@ allOf:
       properties:
         compatible:
           contains:
-            const: fsl,imx8mp-lcdif
+            enum:
+              - fsl,imx8mp-lcdif
+              - fsl,imx93-lcdif
     then:
       properties:
         clocks:
@@ -107,6 +110,7 @@ allOf:
               enum:
                 - fsl,imx6sx-lcdif
                 - fsl,imx8mp-lcdif
+                - fsl,imx93-lcdif
     then:
       properties:
         clocks:
@@ -123,6 +127,7 @@ allOf:
               - fsl,imx8mm-lcdif
               - fsl,imx8mn-lcdif
               - fsl,imx8mp-lcdif
+              - fsl,imx93-lcdif
     then:
       required:
         - power-domains
-- 
2.37.1

[PATCH v2 2/6] drm: lcdif: Drop unnecessary NULL pointer check on lcdif->bridge

[Liu Ying]

A valid bridge is already found in lcdif_attach_bridge() and set
to lcdif->bridge, so lcdif->bridge cannot be a NULL pointer. Drop
the unnecessary NULL pointer check in KMS stage.

Signed-off-by: Liu Ying <victor.liu@nxp.com>
---
v1->v2:
* Split from patch 2/2 in v1. (Marek, Alexander)

 drivers/gpu/drm/mxsfb/lcdif_kms.c | 33 +++++++++++--------------------
 1 file changed, 12 insertions(+), 21 deletions(-)

diff --git a/drivers/gpu/drm/mxsfb/lcdif_kms.c b/drivers/gpu/drm/mxsfb/lcdif_kms.c
index 262bc43b1079..e54200a9fcb9 100644
--- a/drivers/gpu/drm/mxsfb/lcdif_kms.c
+++ b/drivers/gpu/drm/mxsfb/lcdif_kms.c
@@ -394,7 +394,7 @@ static void lcdif_crtc_mode_set_nofb(struct lcdif_drm_private *lcdif,
 	struct drm_display_mode *m = &lcdif->crtc.state->adjusted_mode;
 	u32 bus_flags = 0;
 
-	if (lcdif->bridge && lcdif->bridge->timings)
+	if (lcdif->bridge->timings)
 		bus_flags = lcdif->bridge->timings->input_bus_flags;
 	else if (bridge_state)
 		bus_flags = bridge_state->input_bus_cfg.flags;
@@ -463,30 +463,21 @@ static void lcdif_crtc_atomic_enable(struct drm_crtc *crtc,
 	struct drm_display_mode *m = &lcdif->crtc.state->adjusted_mode;
 	struct drm_bridge_state *bridge_state = NULL;
 	struct drm_device *drm = lcdif->drm;
-	u32 bus_format = 0;
+	u32 bus_format;
 	dma_addr_t paddr;
 
-	/* If there is a bridge attached to the LCDIF, use its bus format */
-	if (lcdif->bridge) {
-		bridge_state =
-			drm_atomic_get_new_bridge_state(state,
-							lcdif->bridge);
-		if (!bridge_state)
-			bus_format = MEDIA_BUS_FMT_FIXED;
-		else
-			bus_format = bridge_state->input_bus_cfg.format;
-
-		if (bus_format == MEDIA_BUS_FMT_FIXED) {
-			dev_warn_once(drm->dev,
-				      "Bridge does not provide bus format, assuming MEDIA_BUS_FMT_RGB888_1X24.\n"
-				      "Please fix bridge driver by handling atomic_get_input_bus_fmts.\n");
-			bus_format = MEDIA_BUS_FMT_RGB888_1X24;
-		}
-	}
+	bridge_state = drm_atomic_get_new_bridge_state(state, lcdif->bridge);
+	if (!bridge_state)
+		bus_format = MEDIA_BUS_FMT_FIXED;
+	else
+		bus_format = bridge_state->input_bus_cfg.format;
 
-	/* If all else fails, default to RGB888_1X24 */
-	if (!bus_format)
+	if (bus_format == MEDIA_BUS_FMT_FIXED) {
+		dev_warn_once(drm->dev,
+			      "Bridge does not provide bus format, assuming MEDIA_BUS_FMT_RGB888_1X24.\n"
+			      "Please fix bridge driver by handling atomic_get_input_bus_fmts.\n");
 		bus_format = MEDIA_BUS_FMT_RGB888_1X24;
+	}
 
 	clk_set_rate(lcdif->clk, m->crtc_clock * 1000);
 
-- 
2.37.1

Re: [PATCH v2 2/6] drm: lcdif: Drop unnecessary NULL pointer check on lcdif->bridge

[Marek Vasut]

On 1/25/23 07:40, Liu Ying wrote:
> A valid bridge is already found in lcdif_attach_bridge() and set
> to lcdif->bridge, so lcdif->bridge cannot be a NULL pointer. Drop
> the unnecessary NULL pointer check in KMS stage.

Is it possible that a panel (instead of a bridge) be attached to LCDIFv3 
e.g. in case of iMXRT ?

> Signed-off-by: Liu Ying <victor.liu@nxp.com>
> ---
> v1->v2:
> * Split from patch 2/2 in v1. (Marek, Alexander)

Much appreciated, thanks.

[...]

Re: [PATCH v2 2/6] drm: lcdif: Drop unnecessary NULL pointer check on lcdif->bridge

[Liu Ying]

On Wed, 2023-01-25 at 14:56 +0100, Marek Vasut wrote:
> On 1/25/23 07:40, Liu Ying wrote:
> > A valid bridge is already found in lcdif_attach_bridge() and set
> > to lcdif->bridge, so lcdif->bridge cannot be a NULL pointer. Drop
> > the unnecessary NULL pointer check in KMS stage.
> 
> Is it possible that a panel (instead of a bridge) be attached to
> LCDIFv3 
> e.g. in case of iMXRT ?

According to IMXRT1160 and IMXRT1170 reference manuals, it looks like
LCDIFv2(similar to LCDIFv3, but not the same) may connect to a parallel
display panel through a mux(either eLCDIF or LCDIFv2).  That mux could
be a bridge.  But, it doesn't matter, because devm_drm_of_get_bridge()
may create a panel bridge if a panel is connected directly(See
kerneldoc of devm_drm_of_get_bridge()).

Regards,
Liu Ying

> 
> > Signed-off-by: Liu Ying <victor.liu@nxp.com>
> > ---
> > v1->v2:
> > * Split from patch 2/2 in v1. (Marek, Alexander)
> 
> Much appreciated, thanks.
> 
> [...]

[PATCH v2 3/6] drm: lcdif: Determine bus format and flags in ->atomic_check()

[Liu Ying]

Instead of determining LCDIF output bus format and bus flags in
->atomic_enable(), do that in ->atomic_check().  This is a
preparation for the upcoming patch to check consistent bus format
and bus flags across all first downstream bridges in ->atomic_check().
New lcdif_crtc_state structure is introduced to cache bus format
and bus flags states in ->atomic_check() so that they can be read
in ->atomic_enable().

Signed-off-by: Liu Ying <victor.liu@nxp.com>
---
v1->v2:
* Split from patch 2/2 in v1. (Marek, Alexander)
* Add comment on the 'base' member of lcdif_crtc_state structure to
  note it should always be the first member. (Lothar)

 drivers/gpu/drm/mxsfb/lcdif_kms.c | 138 ++++++++++++++++++++++--------
 1 file changed, 100 insertions(+), 38 deletions(-)

diff --git a/drivers/gpu/drm/mxsfb/lcdif_kms.c b/drivers/gpu/drm/mxsfb/lcdif_kms.c
index e54200a9fcb9..294cecdf5439 100644
--- a/drivers/gpu/drm/mxsfb/lcdif_kms.c
+++ b/drivers/gpu/drm/mxsfb/lcdif_kms.c
@@ -30,6 +30,18 @@
 #include "lcdif_drv.h"
 #include "lcdif_regs.h"
 
+struct lcdif_crtc_state {
+	struct drm_crtc_state	base;	/* always be the first member */
+	u32			bus_format;
+	u32			bus_flags;
+};
+
+static inline struct lcdif_crtc_state *
+to_lcdif_crtc_state(struct drm_crtc_state *s)
+{
+	return container_of(s, struct lcdif_crtc_state, base);
+}
+
 /* -----------------------------------------------------------------------------
  * CRTC
  */
@@ -385,48 +397,72 @@ static void lcdif_reset_block(struct lcdif_drm_private *lcdif)
 	readl(lcdif->base + LCDC_V8_CTRL);
 }
 
-static void lcdif_crtc_mode_set_nofb(struct lcdif_drm_private *lcdif,
-				     struct drm_plane_state *plane_state,
-				     struct drm_bridge_state *bridge_state,
-				     const u32 bus_format)
+static void lcdif_crtc_mode_set_nofb(struct drm_crtc_state *crtc_state,
+				     struct drm_plane_state *plane_state)
 {
-	struct drm_device *drm = lcdif->crtc.dev;
-	struct drm_display_mode *m = &lcdif->crtc.state->adjusted_mode;
-	u32 bus_flags = 0;
-
-	if (lcdif->bridge->timings)
-		bus_flags = lcdif->bridge->timings->input_bus_flags;
-	else if (bridge_state)
-		bus_flags = bridge_state->input_bus_cfg.flags;
+	struct lcdif_crtc_state *lcdif_crtc_state = to_lcdif_crtc_state(crtc_state);
+	struct drm_device *drm = crtc_state->crtc->dev;
+	struct lcdif_drm_private *lcdif = to_lcdif_drm_private(drm);
+	struct drm_display_mode *m = &crtc_state->adjusted_mode;
 
 	DRM_DEV_DEBUG_DRIVER(drm->dev, "Pixel clock: %dkHz (actual: %dkHz)\n",
 			     m->crtc_clock,
 			     (int)(clk_get_rate(lcdif->clk) / 1000));
 	DRM_DEV_DEBUG_DRIVER(drm->dev, "Bridge bus_flags: 0x%08X\n",
-			     bus_flags);
+			     lcdif_crtc_state->bus_flags);
 	DRM_DEV_DEBUG_DRIVER(drm->dev, "Mode flags: 0x%08X\n", m->flags);
 
 	/* Mandatory eLCDIF reset as per the Reference Manual */
 	lcdif_reset_block(lcdif);
 
-	lcdif_set_formats(lcdif, plane_state, bus_format);
+	lcdif_set_formats(lcdif, plane_state, lcdif_crtc_state->bus_format);
 
-	lcdif_set_mode(lcdif, bus_flags);
+	lcdif_set_mode(lcdif, lcdif_crtc_state->bus_flags);
 }
 
 static int lcdif_crtc_atomic_check(struct drm_crtc *crtc,
 				   struct drm_atomic_state *state)
 {
+	struct drm_device *drm = crtc->dev;
+	struct lcdif_drm_private *lcdif = to_lcdif_drm_private(drm);
 	struct drm_crtc_state *crtc_state = drm_atomic_get_new_crtc_state(state,
 									  crtc);
+	struct lcdif_crtc_state *lcdif_crtc_state = to_lcdif_crtc_state(crtc_state);
 	bool has_primary = crtc_state->plane_mask &
 			   drm_plane_mask(crtc->primary);
+	struct drm_bridge_state *bridge_state;
+	struct drm_bridge *bridge = lcdif->bridge;
+	int ret;
 
 	/* The primary plane has to be enabled when the CRTC is active. */
 	if (crtc_state->active && !has_primary)
 		return -EINVAL;
 
-	return drm_atomic_add_affected_planes(state, crtc);
+	ret = drm_atomic_add_affected_planes(state, crtc);
+	if (ret)
+		return ret;
+
+	bridge_state = drm_atomic_get_new_bridge_state(state, bridge);
+	if (!bridge_state)
+		lcdif_crtc_state->bus_format = MEDIA_BUS_FMT_FIXED;
+	else
+		lcdif_crtc_state->bus_format = bridge_state->input_bus_cfg.format;
+
+	if (lcdif_crtc_state->bus_format == MEDIA_BUS_FMT_FIXED) {
+		dev_warn_once(drm->dev,
+			      "Bridge does not provide bus format, assuming MEDIA_BUS_FMT_RGB888_1X24.\n"
+			      "Please fix bridge driver by handling atomic_get_input_bus_fmts.\n");
+		lcdif_crtc_state->bus_format = MEDIA_BUS_FMT_RGB888_1X24;
+	}
+
+	if (bridge->timings)
+		lcdif_crtc_state->bus_flags = bridge->timings->input_bus_flags;
+	else if (bridge_state)
+		lcdif_crtc_state->bus_flags = bridge_state->input_bus_cfg.flags;
+	else
+		lcdif_crtc_state->bus_flags = 0;
+
+	return 0;
 }
 
 static void lcdif_crtc_atomic_flush(struct drm_crtc *crtc,
@@ -458,35 +494,21 @@ static void lcdif_crtc_atomic_enable(struct drm_crtc *crtc,
 				     struct drm_atomic_state *state)
 {
 	struct lcdif_drm_private *lcdif = to_lcdif_drm_private(crtc->dev);
-	struct drm_plane_state *new_pstate = drm_atomic_get_new_plane_state(state,
-									    crtc->primary);
+	struct drm_crtc_state *new_crtc_state = drm_atomic_get_new_crtc_state(state, crtc);
+	struct drm_plane_state *new_plane_state = drm_atomic_get_new_plane_state(state,
+										 crtc->primary);
 	struct drm_display_mode *m = &lcdif->crtc.state->adjusted_mode;
-	struct drm_bridge_state *bridge_state = NULL;
 	struct drm_device *drm = lcdif->drm;
-	u32 bus_format;
 	dma_addr_t paddr;
 
-	bridge_state = drm_atomic_get_new_bridge_state(state, lcdif->bridge);
-	if (!bridge_state)
-		bus_format = MEDIA_BUS_FMT_FIXED;
-	else
-		bus_format = bridge_state->input_bus_cfg.format;
-
-	if (bus_format == MEDIA_BUS_FMT_FIXED) {
-		dev_warn_once(drm->dev,
-			      "Bridge does not provide bus format, assuming MEDIA_BUS_FMT_RGB888_1X24.\n"
-			      "Please fix bridge driver by handling atomic_get_input_bus_fmts.\n");
-		bus_format = MEDIA_BUS_FMT_RGB888_1X24;
-	}
-
 	clk_set_rate(lcdif->clk, m->crtc_clock * 1000);
 
 	pm_runtime_get_sync(drm->dev);
 
-	lcdif_crtc_mode_set_nofb(lcdif, new_pstate, bridge_state, bus_format);
+	lcdif_crtc_mode_set_nofb(new_crtc_state, new_plane_state);
 
 	/* Write cur_buf as well to avoid an initial corrupt frame */
-	paddr = drm_fb_dma_get_gem_addr(new_pstate->fb, new_pstate, 0);
+	paddr = drm_fb_dma_get_gem_addr(new_plane_state->fb, new_plane_state, 0);
 	if (paddr) {
 		writel(lower_32_bits(paddr),
 		       lcdif->base + LCDC_V8_CTRLDESCL_LOW0_4);
@@ -520,6 +542,46 @@ static void lcdif_crtc_atomic_disable(struct drm_crtc *crtc,
 	pm_runtime_put_sync(drm->dev);
 }
 
+static void lcdif_crtc_reset(struct drm_crtc *crtc)
+{
+	struct lcdif_crtc_state *state;
+
+	if (crtc->state)
+		__drm_atomic_helper_crtc_destroy_state(crtc->state);
+
+	kfree(to_lcdif_crtc_state(crtc->state));
+	crtc->state = NULL;
+
+	state = kzalloc(sizeof(*state), GFP_KERNEL);
+	if (state)
+		__drm_atomic_helper_crtc_reset(crtc, &state->base);
+}
+
+static struct drm_crtc_state *
+lcdif_crtc_atomic_duplicate_state(struct drm_crtc *crtc)
+{
+	struct lcdif_crtc_state *old = to_lcdif_crtc_state(crtc->state);
+	struct lcdif_crtc_state *new;
+
+	new = kzalloc(sizeof(*new), GFP_KERNEL);
+	if (!new)
+		return NULL;
+
+	__drm_atomic_helper_crtc_duplicate_state(crtc, &new->base);
+
+	new->bus_format = old->bus_format;
+	new->bus_flags = old->bus_flags;
+
+	return &new->base;
+}
+
+static void lcdif_crtc_atomic_destroy_state(struct drm_crtc *crtc,
+					    struct drm_crtc_state *state)
+{
+	__drm_atomic_helper_crtc_destroy_state(state);
+	kfree(to_lcdif_crtc_state(state));
+}
+
 static int lcdif_crtc_enable_vblank(struct drm_crtc *crtc)
 {
 	struct lcdif_drm_private *lcdif = to_lcdif_drm_private(crtc->dev);
@@ -548,12 +610,12 @@ static const struct drm_crtc_helper_funcs lcdif_crtc_helper_funcs = {
 };
 
 static const struct drm_crtc_funcs lcdif_crtc_funcs = {
-	.reset = drm_atomic_helper_crtc_reset,
+	.reset = lcdif_crtc_reset,
 	.destroy = drm_crtc_cleanup,
 	.set_config = drm_atomic_helper_set_config,
 	.page_flip = drm_atomic_helper_page_flip,
-	.atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
-	.atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
+	.atomic_duplicate_state = lcdif_crtc_atomic_duplicate_state,
+	.atomic_destroy_state = lcdif_crtc_atomic_destroy_state,
 	.enable_vblank = lcdif_crtc_enable_vblank,
 	.disable_vblank = lcdif_crtc_disable_vblank,
 };
-- 
2.37.1

[PATCH v2 4/6] drm: lcdif: Check consistent bus format and flags across first bridges

[Liu Ying]

The single LCDIF embedded in i.MX93 SoC may drive multiple displays
simultaneously.  Check bus format and flags across first bridges in
->atomic_check() to ensure they are consistent.  This is a preparation
for adding i.MX93 LCDIF support.

Signed-off-by: Liu Ying <victor.liu@nxp.com>
---
v1->v2:
* Split from patch 2/2 in v1. (Marek, Alexander)
* Drop a comment about bridge input bus format from lcdif_crtc_atomic_check().

 drivers/gpu/drm/mxsfb/lcdif_drv.c |  2 -
 drivers/gpu/drm/mxsfb/lcdif_drv.h |  1 -
 drivers/gpu/drm/mxsfb/lcdif_kms.c | 76 ++++++++++++++++++++++---------
 3 files changed, 55 insertions(+), 24 deletions(-)

diff --git a/drivers/gpu/drm/mxsfb/lcdif_drv.c b/drivers/gpu/drm/mxsfb/lcdif_drv.c
index cc2ceb301b96..b5b9a8e273c6 100644
--- a/drivers/gpu/drm/mxsfb/lcdif_drv.c
+++ b/drivers/gpu/drm/mxsfb/lcdif_drv.c
@@ -52,8 +52,6 @@ static int lcdif_attach_bridge(struct lcdif_drm_private *lcdif)
 	if (ret)
 		return dev_err_probe(drm->dev, ret, "Failed to attach bridge\n");
 
-	lcdif->bridge = bridge;
-
 	return 0;
 }
 
diff --git a/drivers/gpu/drm/mxsfb/lcdif_drv.h b/drivers/gpu/drm/mxsfb/lcdif_drv.h
index 6cdba6e20c02..aa6d099a1897 100644
--- a/drivers/gpu/drm/mxsfb/lcdif_drv.h
+++ b/drivers/gpu/drm/mxsfb/lcdif_drv.h
@@ -31,7 +31,6 @@ struct lcdif_drm_private {
 	} planes;
 	struct drm_crtc			crtc;
 	struct drm_encoder		encoder;
-	struct drm_bridge		*bridge;
 };
 
 static inline struct lcdif_drm_private *
diff --git a/drivers/gpu/drm/mxsfb/lcdif_kms.c b/drivers/gpu/drm/mxsfb/lcdif_kms.c
index 294cecdf5439..4ea3d2b2cf61 100644
--- a/drivers/gpu/drm/mxsfb/lcdif_kms.c
+++ b/drivers/gpu/drm/mxsfb/lcdif_kms.c
@@ -17,6 +17,7 @@
 #include <drm/drm_atomic_helper.h>
 #include <drm/drm_bridge.h>
 #include <drm/drm_color_mgmt.h>
+#include <drm/drm_connector.h>
 #include <drm/drm_crtc.h>
 #include <drm/drm_encoder.h>
 #include <drm/drm_fb_dma_helper.h>
@@ -424,15 +425,19 @@ static int lcdif_crtc_atomic_check(struct drm_crtc *crtc,
 				   struct drm_atomic_state *state)
 {
 	struct drm_device *drm = crtc->dev;
-	struct lcdif_drm_private *lcdif = to_lcdif_drm_private(drm);
 	struct drm_crtc_state *crtc_state = drm_atomic_get_new_crtc_state(state,
 									  crtc);
 	struct lcdif_crtc_state *lcdif_crtc_state = to_lcdif_crtc_state(crtc_state);
 	bool has_primary = crtc_state->plane_mask &
 			   drm_plane_mask(crtc->primary);
+	struct drm_connector_state *connector_state;
+	struct drm_connector *connector;
+	struct drm_encoder *encoder;
 	struct drm_bridge_state *bridge_state;
-	struct drm_bridge *bridge = lcdif->bridge;
-	int ret;
+	struct drm_bridge *bridge;
+	u32 bus_format, bus_flags;
+	bool format_set = false, flags_set = false;
+	int ret, i;
 
 	/* The primary plane has to be enabled when the CRTC is active. */
 	if (crtc_state->active && !has_primary)
@@ -442,26 +447,55 @@ static int lcdif_crtc_atomic_check(struct drm_crtc *crtc,
 	if (ret)
 		return ret;
 
-	bridge_state = drm_atomic_get_new_bridge_state(state, bridge);
-	if (!bridge_state)
-		lcdif_crtc_state->bus_format = MEDIA_BUS_FMT_FIXED;
-	else
-		lcdif_crtc_state->bus_format = bridge_state->input_bus_cfg.format;
-
-	if (lcdif_crtc_state->bus_format == MEDIA_BUS_FMT_FIXED) {
-		dev_warn_once(drm->dev,
-			      "Bridge does not provide bus format, assuming MEDIA_BUS_FMT_RGB888_1X24.\n"
-			      "Please fix bridge driver by handling atomic_get_input_bus_fmts.\n");
-		lcdif_crtc_state->bus_format = MEDIA_BUS_FMT_RGB888_1X24;
+	/* Try to find consistent bus format and flags across first bridges. */
+	for_each_new_connector_in_state(state, connector, connector_state, i) {
+		if (!connector_state->crtc)
+			continue;
+
+		encoder = connector_state->best_encoder;
+
+		bridge = drm_bridge_chain_get_first_bridge(encoder);
+		if (!bridge)
+			continue;
+
+		bridge_state = drm_atomic_get_new_bridge_state(state, bridge);
+		if (!bridge_state)
+			bus_format = MEDIA_BUS_FMT_FIXED;
+		else
+			bus_format = bridge_state->input_bus_cfg.format;
+
+		if (bus_format == MEDIA_BUS_FMT_FIXED) {
+			dev_warn(drm->dev,
+				 "[ENCODER:%d:%s]'s bridge does not provide bus format, assuming MEDIA_BUS_FMT_RGB888_1X24.\n"
+				 "Please fix bridge driver by handling atomic_get_input_bus_fmts.\n",
+				 encoder->base.id, encoder->name);
+			bus_format = MEDIA_BUS_FMT_RGB888_1X24;
+		}
+
+		if (!format_set) {
+			lcdif_crtc_state->bus_format = bus_format;
+			format_set = true;
+		} else if (lcdif_crtc_state->bus_format != bus_format) {
+			DRM_DEV_DEBUG_DRIVER(drm->dev, "inconsistent bus format\n");
+			return -EINVAL;
+		}
+
+		if (bridge->timings)
+			bus_flags = bridge->timings->input_bus_flags;
+		else if (bridge_state)
+			bus_flags = bridge_state->input_bus_cfg.flags;
+		else
+			bus_flags = 0;
+
+		if (!flags_set) {
+			lcdif_crtc_state->bus_flags = bus_flags;
+			flags_set = true;
+		} else if (lcdif_crtc_state->bus_flags != bus_flags) {
+			DRM_DEV_DEBUG_DRIVER(drm->dev, "inconsistent bus flags\n");
+			return -EINVAL;
+		}
 	}
 
-	if (bridge->timings)
-		lcdif_crtc_state->bus_flags = bridge->timings->input_bus_flags;
-	else if (bridge_state)
-		lcdif_crtc_state->bus_flags = bridge_state->input_bus_cfg.flags;
-	else
-		lcdif_crtc_state->bus_flags = 0;
-
 	return 0;
 }
 
-- 
2.37.1

[PATCH v2 5/6] drm: lcdif: Add multiple encoders and first bridges support

[Liu Ying]

The single LCDIF embedded in i.MX93 SoC may drive multiple displays
simultaneously.  Look at LCDIF output port's remote port parents to
find all enabled first bridges.  Add an encoder for each found bridge
and attach the bridge to the encoder.  This is a preparation for
adding i.MX93 LCDIF support.

Signed-off-by: Liu Ying <victor.liu@nxp.com>
---
v1->v2:
* Split from patch 2/2 in v1. (Marek, Alexander)
* Drop '!remote ||' from lcdif_attach_bridge(). (Lothar)
* Drop unneeded 'bridges' member from lcdif_drm_private structure.

 drivers/gpu/drm/mxsfb/lcdif_drv.c | 68 +++++++++++++++++++++++++++----
 drivers/gpu/drm/mxsfb/lcdif_drv.h |  4 +-
 drivers/gpu/drm/mxsfb/lcdif_kms.c | 21 ++--------
 3 files changed, 66 insertions(+), 27 deletions(-)

diff --git a/drivers/gpu/drm/mxsfb/lcdif_drv.c b/drivers/gpu/drm/mxsfb/lcdif_drv.c
index b5b9a8e273c6..eb6c265fa2fe 100644
--- a/drivers/gpu/drm/mxsfb/lcdif_drv.c
+++ b/drivers/gpu/drm/mxsfb/lcdif_drv.c
@@ -9,13 +9,16 @@
 #include <linux/dma-mapping.h>
 #include <linux/io.h>
 #include <linux/module.h>
+#include <linux/of.h>
 #include <linux/of_device.h>
+#include <linux/of_graph.h>
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
 
 #include <drm/drm_atomic_helper.h>
 #include <drm/drm_bridge.h>
 #include <drm/drm_drv.h>
+#include <drm/drm_encoder.h>
 #include <drm/drm_fbdev_generic.h>
 #include <drm/drm_gem_dma_helper.h>
 #include <drm/drm_gem_framebuffer_helper.h>
@@ -38,19 +41,68 @@ static const struct drm_mode_config_helper_funcs lcdif_mode_config_helpers = {
 	.atomic_commit_tail = drm_atomic_helper_commit_tail_rpm,
 };
 
+static const struct drm_encoder_funcs lcdif_encoder_funcs = {
+	.destroy = drm_encoder_cleanup,
+};
+
 static int lcdif_attach_bridge(struct lcdif_drm_private *lcdif)
 {
-	struct drm_device *drm = lcdif->drm;
+	struct device *dev = lcdif->drm->dev;
+	struct device_node *ep;
 	struct drm_bridge *bridge;
 	int ret;
 
-	bridge = devm_drm_of_get_bridge(drm->dev, drm->dev->of_node, 0, 0);
-	if (IS_ERR(bridge))
-		return PTR_ERR(bridge);
-
-	ret = drm_bridge_attach(&lcdif->encoder, bridge, NULL, 0);
-	if (ret)
-		return dev_err_probe(drm->dev, ret, "Failed to attach bridge\n");
+	for_each_endpoint_of_node(dev->of_node, ep) {
+		struct device_node *remote;
+		struct of_endpoint of_ep;
+		struct drm_encoder *encoder;
+
+		remote = of_graph_get_remote_port_parent(ep);
+		if (!of_device_is_available(remote)) {
+			of_node_put(remote);
+			continue;
+		}
+		of_node_put(remote);
+
+		ret = of_graph_parse_endpoint(ep, &of_ep);
+		if (ret < 0) {
+			dev_err(dev, "Failed to parse endpoint %pOF\n", ep);
+			of_node_put(ep);
+			return ret;
+		}
+
+		if (of_ep.id >= MAX_DISPLAYS) {
+			dev_warn(dev, "invalid endpoint id %u\n", of_ep.id);
+			continue;
+		}
+
+		bridge = devm_drm_of_get_bridge(dev, dev->of_node, 0, of_ep.id);
+		if (IS_ERR(bridge)) {
+			of_node_put(ep);
+			return dev_err_probe(dev, PTR_ERR(bridge),
+					     "Failed to get bridge for endpoint%u\n",
+					     of_ep.id);
+		}
+
+		encoder = &lcdif->encoders[of_ep.id];
+		encoder->possible_crtcs = drm_crtc_mask(&lcdif->crtc);
+		ret = drm_encoder_init(lcdif->drm, encoder, &lcdif_encoder_funcs,
+				       DRM_MODE_ENCODER_NONE, NULL);
+		if (ret) {
+			dev_err(dev, "Failed to initialize encoder for endpoint%u: %d\n",
+				of_ep.id, ret);
+			of_node_put(ep);
+			return ret;
+		}
+
+		ret = drm_bridge_attach(encoder, bridge, NULL, 0);
+		if (ret) {
+			of_node_put(ep);
+			return dev_err_probe(dev, ret,
+					     "Failed to attach bridge for endpoint%u\n",
+					     of_ep.id);
+		}
+	}
 
 	return 0;
 }
diff --git a/drivers/gpu/drm/mxsfb/lcdif_drv.h b/drivers/gpu/drm/mxsfb/lcdif_drv.h
index aa6d099a1897..c7400bd9bbd9 100644
--- a/drivers/gpu/drm/mxsfb/lcdif_drv.h
+++ b/drivers/gpu/drm/mxsfb/lcdif_drv.h
@@ -14,6 +14,8 @@
 #include <drm/drm_encoder.h>
 #include <drm/drm_plane.h>
 
+#define MAX_DISPLAYS	3
+
 struct clk;
 
 struct lcdif_drm_private {
@@ -30,7 +32,7 @@ struct lcdif_drm_private {
 		/* i.MXRT does support overlay planes, add them here. */
 	} planes;
 	struct drm_crtc			crtc;
-	struct drm_encoder		encoder;
+	struct drm_encoder		encoders[MAX_DISPLAYS];
 };
 
 static inline struct lcdif_drm_private *
diff --git a/drivers/gpu/drm/mxsfb/lcdif_kms.c b/drivers/gpu/drm/mxsfb/lcdif_kms.c
index 4ea3d2b2cf61..5f34d01e133e 100644
--- a/drivers/gpu/drm/mxsfb/lcdif_kms.c
+++ b/drivers/gpu/drm/mxsfb/lcdif_kms.c
@@ -654,14 +654,6 @@ static const struct drm_crtc_funcs lcdif_crtc_funcs = {
 	.disable_vblank = lcdif_crtc_disable_vblank,
 };
 
-/* -----------------------------------------------------------------------------
- * Encoder
- */
-
-static const struct drm_encoder_funcs lcdif_encoder_funcs = {
-	.destroy = drm_encoder_cleanup,
-};
-
 /* -----------------------------------------------------------------------------
  * Planes
  */
@@ -754,7 +746,6 @@ int lcdif_kms_init(struct lcdif_drm_private *lcdif)
 					BIT(DRM_COLOR_YCBCR_BT2020);
 	const u32 supported_ranges = BIT(DRM_COLOR_YCBCR_LIMITED_RANGE) |
 				     BIT(DRM_COLOR_YCBCR_FULL_RANGE);
-	struct drm_encoder *encoder = &lcdif->encoder;
 	struct drm_crtc *crtc = &lcdif->crtc;
 	int ret;
 
@@ -778,13 +769,7 @@ int lcdif_kms_init(struct lcdif_drm_private *lcdif)
 		return ret;
 
 	drm_crtc_helper_add(crtc, &lcdif_crtc_helper_funcs);
-	ret = drm_crtc_init_with_planes(lcdif->drm, crtc,
-					&lcdif->planes.primary, NULL,
-					&lcdif_crtc_funcs, NULL);
-	if (ret)
-		return ret;
-
-	encoder->possible_crtcs = drm_crtc_mask(crtc);
-	return drm_encoder_init(lcdif->drm, encoder, &lcdif_encoder_funcs,
-				DRM_MODE_ENCODER_NONE, NULL);
+	return drm_crtc_init_with_planes(lcdif->drm, crtc,
+					 &lcdif->planes.primary, NULL,
+					 &lcdif_crtc_funcs, NULL);
 }
-- 
2.37.1

[PATCH v2 6/6] drm: lcdif: Add i.MX93 LCDIF compatible string

[Liu Ying]

With all previous preparations done to make it possible for the
single LCDIF embedded in i.MX93 SoC to drive multipledisplays
simultaneously, add i.MX93 LCDIF compatible string as the last
step of adding i.MX93 LCDIF support.

Signed-off-by: Liu Ying <victor.liu@nxp.com>
---
 drivers/gpu/drm/mxsfb/lcdif_drv.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/mxsfb/lcdif_drv.c b/drivers/gpu/drm/mxsfb/lcdif_drv.c
index eb6c265fa2fe..48c43b273a4a 100644
--- a/drivers/gpu/drm/mxsfb/lcdif_drv.c
+++ b/drivers/gpu/drm/mxsfb/lcdif_drv.c
@@ -249,6 +249,7 @@ static const struct drm_driver lcdif_driver = {
 
 static const struct of_device_id lcdif_dt_ids[] = {
 	{ .compatible = "fsl,imx8mp-lcdif" },
+	{ .compatible = "fsl,imx93-lcdif" },
 	{ /* sentinel */ }
 };
 MODULE_DEVICE_TABLE(of, lcdif_dt_ids);
-- 
2.37.1