[PATCH 1/2] drm_modes: videomode: add pos/neg pixel clock polarity flag

[PATCH 1/2] drm_modes: videomode: add pos/neg pixel clock polarity flag

[Sébastien Szymanski]

From: Steve Longerbeam <steve_longerbeam@mentor.com>

[Sébastien - rebase, update drm_display_mode_to_videomode function]

Signed-off-by: Steve Longerbeam <steve_longerbeam@mentor.com>
Signed-off-by: Sébastien Szymanski <sebastien.szymanski@armadeus.com>
---
 drivers/gpu/drm/drm_modes.c | 8 ++++++++
 include/uapi/drm/drm_mode.h | 4 ++++
 2 files changed, 12 insertions(+)

diff --git a/drivers/gpu/drm/drm_modes.c b/drivers/gpu/drm/drm_modes.c
index 487d0e3..464828f 100644
--- a/drivers/gpu/drm/drm_modes.c
+++ b/drivers/gpu/drm/drm_modes.c
@@ -611,6 +611,10 @@ void drm_display_mode_from_videomode(const struct videomode *vm,
 		dmode->flags |= DRM_MODE_FLAG_DBLSCAN;
 	if (vm->flags & DISPLAY_FLAGS_DOUBLECLK)
 		dmode->flags |= DRM_MODE_FLAG_DBLCLK;
+	if (vm->flags & DISPLAY_FLAGS_PIXDATA_POSEDGE)
+		dmode->flags |= DRM_MODE_FLAG_PCLK;
+	else if (vm->flags & DISPLAY_FLAGS_PIXDATA_NEGEDGE)
+		dmode->flags |= DRM_MODE_FLAG_NCLK;
 	drm_mode_set_name(dmode);
 }
 EXPORT_SYMBOL_GPL(drm_display_mode_from_videomode);
@@ -652,6 +656,10 @@ void drm_display_mode_to_videomode(const struct drm_display_mode *dmode,
 		vm->flags |= DISPLAY_FLAGS_DOUBLESCAN;
 	if (dmode->flags & DRM_MODE_FLAG_DBLCLK)
 		vm->flags |= DISPLAY_FLAGS_DOUBLECLK;
+	if (dmode->flags & DRM_MODE_FLAG_PCLK)
+		vm->flags |= DISPLAY_FLAGS_PIXDATA_POSEDGE;
+	else if (dmode->flags & DRM_MODE_FLAG_NCLK)
+		vm->flags |= DISPLAY_FLAGS_PIXDATA_NEGEDGE;
 }
 EXPORT_SYMBOL_GPL(drm_display_mode_to_videomode);
 
diff --git a/include/uapi/drm/drm_mode.h b/include/uapi/drm/drm_mode.h
index ca788e0..1abb2fc 100644
--- a/include/uapi/drm/drm_mode.h
+++ b/include/uapi/drm/drm_mode.h
@@ -72,6 +72,10 @@
 #define  DRM_MODE_FLAG_3D_L_DEPTH_GFX_GFX_DEPTH	(6<<14)
 #define  DRM_MODE_FLAG_3D_TOP_AND_BOTTOM	(7<<14)
 #define  DRM_MODE_FLAG_3D_SIDE_BY_SIDE_HALF	(8<<14)
+/* drive data on rising pixclk edge */
+#define DRM_MODE_FLAG_PCLK			(1<<19)
+/* drive data on falling pixclk edge */
+#define DRM_MODE_FLAG_NCLK			(1<<20)
 
 
 /* DPMS flags */
-- 
2.0.5

[PATCH 2/2] imx-drm: ipuv3-crtc: Use DRM mode flags to configure pixel clock polarity

[Sébastien Szymanski]

From: Steve Longerbeam <steve_longerbeam@mentor.com>

Previously, pixel clock polarity was hardcoded and wasn't configurable.
This patch adds support to configure the pixel clock polarity from the
DRM mode flags.

[Sébastien - rebase]

Signed-off-by: Mohsin Kazmi <mohsin_kazmi@mentor.com>
Signed-off-by: Steve Longerbeam <steve_longerbeam@mentor.com>
Signed-off-by: Sébastien Szymanski <sebastien.szymanski@armadeus.com>
---
 drivers/gpu/drm/imx/ipuv3-crtc.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/imx/ipuv3-crtc.c b/drivers/gpu/drm/imx/ipuv3-crtc.c
index 98551e3..71f888b 100644
--- a/drivers/gpu/drm/imx/ipuv3-crtc.c
+++ b/drivers/gpu/drm/imx/ipuv3-crtc.c
@@ -171,10 +171,12 @@ static int ipu_crtc_mode_set(struct drm_crtc *crtc,
 	else
 		sig_cfg.clkflags = 0;
 
+	if (mode->flags & DRM_MODE_FLAG_PCLK)
+		sig_cfg.clk_pol = 1;
+
 	out_pixel_fmt = ipu_crtc->interface_pix_fmt;
 
 	sig_cfg.enable_pol = 1;
-	sig_cfg.clk_pol = 0;
 	sig_cfg.pixel_fmt = out_pixel_fmt;
 	sig_cfg.v_to_h_sync = 0;
 	sig_cfg.hsync_pin = ipu_crtc->di_hsync_pin;
-- 
2.0.5

Re: [PATCH 1/2] drm_modes: videomode: add pos/neg pixel clock polarity flag

[Philipp Zabel]

Hi Sébastien,

Am Montag, den 16.03.2015, 18:29 +0100 schrieb Sébastien Szymanski:
> From: Steve Longerbeam <steve_longerbeam@mentor.com>
> 
> [Sébastien - rebase, update drm_display_mode_to_videomode function]
> 
> Signed-off-by: Steve Longerbeam <steve_longerbeam@mentor.com>
> Signed-off-by: Sébastien Szymanski <sebastien.szymanski@armadeus.com>

Thanks for bringing this up again. This is a very crucial bit of
information that somehow needs to be communicated from the panel driver
to the crtc/encoder drivers. I vaguely remember that an earlier attempt
to add this flag to the userspace visible DRM_MODE_FLAGs was met with
resistance before, but I can't find it right now.

regards
Philipp