4.19-stable review patch. If anyone has any objections, please let me know.
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From: Christoph Niedermaier cniedermaier@dh-electronics.com
commit 6061806a863e8b65b109eb06a280041cc7525442 upstream.
If display timings were read from the devicetree using of_get_display_timing() and pixelclk-active is defined there, the flag DISPLAY_FLAGS_SYNC_POSEDGE/NEGEDGE is automatically generated. Through the function drm_bus_flags_from_videomode() e.g. called in the panel-simple driver this flag got into the bus flags, but then in imx_pd_bridge_atomic_check() the bus flag check failed and will not initialize the display. The original commit fe141cedc433 does not explain why this check was introduced. So remove the bus flags check, because it stops the initialization of the display with valid bus flags.
Fixes: fe141cedc433 ("drm/imx: pd: Use bus format/flags provided by the bridge when available") Signed-off-by: Christoph Niedermaier cniedermaier@dh-electronics.com Cc: Marek Vasut marex@denx.de Cc: Boris Brezillon boris.brezillon@collabora.com Cc: Philipp Zabel p.zabel@pengutronix.de Cc: David Airlie airlied@linux.ie Cc: Daniel Vetter daniel@ffwll.ch Cc: Shawn Guo shawnguo@kernel.org Cc: Sascha Hauer s.hauer@pengutronix.de Cc: Pengutronix Kernel Team kernel@pengutronix.de Cc: Fabio Estevam festevam@gmail.com Cc: NXP Linux Team linux-imx@nxp.com Cc: linux-arm-kernel@lists.infradead.org To: dri-devel@lists.freedesktop.org Tested-by: Max Krummenacher max.krummenacher@toradex.com Acked-by: Boris Brezillon boris.brezillon@collabora.com Signed-off-by: Marek Vasut marex@denx.de Link: https://patchwork.freedesktop.org/patch/msgid/20220201113643.4638-1-cniederm... Signed-off-by: Maarten Lankhorst maarten.lankhorst@linux.intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/imx/parallel-display.c | 8 -------- 1 file changed, 8 deletions(-)
--- a/drivers/gpu/drm/imx/parallel-display.c +++ b/drivers/gpu/drm/imx/parallel-display.c @@ -235,14 +235,6 @@ static int imx_pd_bridge_atomic_check(st if (!imx_pd_format_supported(bus_fmt)) return -EINVAL;
- if (bus_flags & - ~(DRM_BUS_FLAG_DE_LOW | DRM_BUS_FLAG_DE_HIGH | - DRM_BUS_FLAG_PIXDATA_DRIVE_POSEDGE | - DRM_BUS_FLAG_PIXDATA_DRIVE_NEGEDGE)) { - dev_warn(imxpd->dev, "invalid bus_flags (%x)\n", bus_flags); - return -EINVAL; - } - bridge_state->output_bus_cfg.flags = bus_flags; bridge_state->input_bus_cfg.flags = bus_flags; imx_crtc_state->bus_flags = bus_flags;