linux/drivers/gpu/drm/rcar-du/rcar_lvds.h
Laurent Pinchart 187502afe8 drm: rcar-du: Don't create encoder for unconnected LVDS outputs
On R-Car D3 and E3, the LVDS encoders provide the pixel clock to the DU,
even when LVDS outputs are not used. For this reason, the rcar-lvds
driver probes successfully on those platforms even if no further bridge
or panel is connected to the LVDS output, in order to provide the
rcar_lvds_clk_enable() and rcar_lvds_clk_disable() functions to the DU
driver.

If an LVDS output isn't connected, trying to create a DRM connector for
the output will fail. Fix this by skipping connector creation in that
case, and also skip creation of the DRM encoder as there's no point in
an encoder without a connector.

Fixes: e9e056949c92 ("drm: rcar-du: lvds: Convert to DRM panel bridge helper")
Reported-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
2021-10-07 05:42:02 +03:00

38 lines
992 B
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* rcar_lvds.h -- R-Car LVDS Encoder
*
* Copyright (C) 2013-2018 Renesas Electronics Corporation
*
* Contact: Laurent Pinchart (laurent.pinchart@ideasonboard.com)
*/
#ifndef __RCAR_LVDS_H__
#define __RCAR_LVDS_H__
struct drm_bridge;
#if IS_ENABLED(CONFIG_DRM_RCAR_LVDS)
int rcar_lvds_clk_enable(struct drm_bridge *bridge, unsigned long freq);
void rcar_lvds_clk_disable(struct drm_bridge *bridge);
bool rcar_lvds_dual_link(struct drm_bridge *bridge);
bool rcar_lvds_is_connected(struct drm_bridge *bridge);
#else
static inline int rcar_lvds_clk_enable(struct drm_bridge *bridge,
unsigned long freq)
{
return -ENOSYS;
}
static inline void rcar_lvds_clk_disable(struct drm_bridge *bridge) { }
static inline bool rcar_lvds_dual_link(struct drm_bridge *bridge)
{
return false;
}
static inline bool rcar_lvds_is_connected(struct drm_bridge *bridge)
{
return false;
}
#endif /* CONFIG_DRM_RCAR_LVDS */
#endif /* __RCAR_LVDS_H__ */