[PATCH v13 06/10] drm: drm_display_mode: add signal polarity flags
Denis Carikli
denis at eukrea.com
Tue Jun 10 03:25:47 PDT 2014
We need a way to pass signal polarity informations
between DRM panels, and the display drivers.
To do that, a pol_flags field was added to drm_display_mode.
Signed-off-by: Denis Carikli <denis at eukrea.com>
---
ChangeLog v12->v13:
- Added Docbook documentation for pol_flags the struct field.
- Removed the _PRESERVE defines: it was used by patches
against the imx_drm driver. Now theses patches have been
adapted not to require that defines.
ChangeLog v11->v12:
- Rebased: This patch now applies against drm_modes.h
- Rebased: It now uses the new DRM_MODE_FLAG_POL_DE flags defines names
ChangeLog v10->v11:
- Since the imx-drm won't be able to retrive its regulators
from the device tree when using display-timings nodes,
and that I was told that the drm simple-panel driver
already supported that, I then, instead, added what was
lacking to make the eukrea displays work with the
drm-simple-panel driver.
That required a way to get back the display polarity
informations from the imx-drm driver without affecting
userspace.
---
Documentation/DocBook/drm.tmpl | 30 ++++++++++++++++++++++++++++++
include/drm/drm_modes.h | 6 ++++++
2 files changed, 36 insertions(+)
diff --git a/Documentation/DocBook/drm.tmpl b/Documentation/DocBook/drm.tmpl
index c526d81..29c0e5a 100644
--- a/Documentation/DocBook/drm.tmpl
+++ b/Documentation/DocBook/drm.tmpl
@@ -2292,6 +2292,36 @@ void intel_crt_init(struct drm_device *dev)
and <structfield>height_mm</structfield> fields are only used internally
during EDID parsing and should not be set when creating modes manually.
</para>
+ <para>
+ The <structfield>pol_flags</structfield> value represents the display
+ signal polarity flags, it can be a combination of
+ <variablelist>
+ <varlistentry>
+ <term>DRM_MODE_FLAG_POL_PIXDATA_NEGEDGE</term>
+ <listitem><para>
+ drive pixel data on falling edge, sample data on rising edge.
+ </para></listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>DRM_MODE_FLAG_POL_PIXDATA_POSEDGE</term>
+ <listitem><para>
+ Drive pixel data on rising edge, sample data on falling edge.
+ </para></listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>DRM_MODE_FLAG_POL_DE_LOW</term>
+ <listitem><para>
+ data-enable pulse is active low
+ </para></listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>DRM_MODE_FLAG_POL_DE_HIGH</term>
+ <listitem><para>
+ data-enable pulse is active low
+ </para></listitem>
+ </varlistentry>
+ </variablelist>
+ </para>
</listitem>
<listitem>
<synopsis>int (*mode_valid)(struct drm_connector *connector,
diff --git a/include/drm/drm_modes.h b/include/drm/drm_modes.h
index 91d0582..c5cbe31 100644
--- a/include/drm/drm_modes.h
+++ b/include/drm/drm_modes.h
@@ -93,6 +93,11 @@ enum drm_mode_status {
#define DRM_MODE_FLAG_3D_MAX DRM_MODE_FLAG_3D_SIDE_BY_SIDE_HALF
+#define DRM_MODE_FLAG_POL_PIXDATA_NEGEDGE BIT(1)
+#define DRM_MODE_FLAG_POL_PIXDATA_POSEDGE BIT(2)
+#define DRM_MODE_FLAG_POL_DE_LOW BIT(3)
+#define DRM_MODE_FLAG_POL_DE_HIGH BIT(4)
+
struct drm_display_mode {
/* Header */
struct list_head head;
@@ -144,6 +149,7 @@ struct drm_display_mode {
int vrefresh; /* in Hz */
int hsync; /* in kHz */
enum hdmi_picture_aspect picture_aspect_ratio;
+ unsigned int pol_flags;
};
/* mode specified on the command line */
--
1.7.9.5
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