Commit d23286ff authored by Stefan Agner's avatar Stefan Agner Committed by Tomi Valkeinen
Browse files

drm/bridge: use bus flags in bridge timings 



The DRM bus flags convey additional information on pixel data on
the bus. All current available bus flags might be of interest for
a bridge. Remove the sampling_edge field and use bus_flags.

In the case at hand a dumb VGA bridge needs a specific data enable
polarity (DRM_BUS_FLAG_DE_LOW).

Signed-off-by: default avatarStefan Agner <stefan@agner.ch>
Signed-off-by: default avatarLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: default avatarTomi Valkeinen <tomi.valkeinen@ti.com>
Tested-by: default avatarSebastian Reichel <sebastian.reichel@collabora.com>
Signed-off-by: default avatarTomi Valkeinen <tomi.valkeinen@ti.com>
parent 88bc4178

drivers/gpu/drm/bridge/dumb-vga-dac.c

+3 −3
Original line number Diff line number Diff line
@@ -234,7 +234,7 @@ static int dumb_vga_remove(struct platform_device *pdev) 
 */

static const struct drm_bridge_timings default_dac_timings = {

	/* Timing specifications, datasheet page 7 */

	.sampling_edge = DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE,

	.input_bus_flags = DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE,

	.setup_time_ps = 500,

	.hold_time_ps = 1500,

};
@@ -245,7 +245,7 @@ static const struct drm_bridge_timings default_dac_timings = { 
 */

static const struct drm_bridge_timings ti_ths8134_dac_timings = {

	/* From timing diagram, datasheet page 9 */

	.sampling_edge = DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE,

	.input_bus_flags = DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE,

	/* From datasheet, page 12 */

	.setup_time_ps = 3000,

	/* I guess this means latched input */
@@ -258,7 +258,7 @@ static const struct drm_bridge_timings ti_ths8134_dac_timings = { 
 */

static const struct drm_bridge_timings ti_ths8135_dac_timings = {

	/* From timing diagram, datasheet page 14 */

	.sampling_edge = DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE,

	.input_bus_flags = DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE,

	/* From datasheet, page 16 */

	.setup_time_ps = 2000,

	.hold_time_ps = 500,

include/drm/drm_bridge.h

+5 −7
Original line number Diff line number Diff line
@@ -244,15 +244,13 @@ struct drm_bridge_funcs { 
 */

struct drm_bridge_timings {

	/**

	 * @sampling_edge:

	 * @input_bus_flags:

	 *

	 * Tells whether the bridge samples the digital input signals from the

	 * display engine on the positive or negative edge of the clock. This

	 * should use the DRM_BUS_FLAG_PIXDATA_SAMPLE_[POS|NEG]EDGE and

	 * DRM_BUS_FLAG_SYNC_SAMPLE_[POS|NEG]EDGE bitwise flags from the DRM

	 * connector (bit 2, 3, 6 and 7 valid).

	 * Tells what additional settings for the pixel data on the bus

	 * this bridge requires (like pixel signal polarity). See also

	 * &drm_display_info->bus_flags.

	 */

	u32 sampling_edge;

	u32 input_bus_flags;

	/**

	 * @setup_time_ps:

	 *

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