Hi Jonathan,
Am Dienstag, 16. März 2021, 19:27:53 CET schrieb Jonathan McDowell:
The Rockchip RGB CRTC output driver attempts to avoid probing Rockchip subdrivers to see if they're a connected panel or bridge. However part of its checks assumes that if no OF platform device is found then it can't be a valid bridge or panel. This causes issues with I2C controlled bridges that have not yet been registered to the point they can be found.
Change this to return EPROBE_DEFER instead of ENODEV and don't ignore such devices. The subsequent call to drm_of_find_panel_or_bridge() will return EPROBE_DEFER as well if there's actually a valid device we should wait for.
Signed-off-by: Jonathan McDowell noodles@earth.li
drivers/gpu/drm/rockchip/rockchip_drm_drv.c | 8 ++++++-- drivers/gpu/drm/rockchip/rockchip_rgb.c | 7 ++++--- 2 files changed, 10 insertions(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_drv.c b/drivers/gpu/drm/rockchip/rockchip_drm_drv.c index 212bd87c0c4a..b0d63a566501 100644 --- a/drivers/gpu/drm/rockchip/rockchip_drm_drv.c +++ b/drivers/gpu/drm/rockchip/rockchip_drm_drv.c @@ -270,11 +270,15 @@ int rockchip_drm_endpoint_is_subdriver(struct device_node *ep) if (!node) return -ENODEV;
- /* status disabled will prevent creation of platform-devices */
- /*
* status disabled will prevent creation of platform-devices,* but equally we can't rely on the driver having been registered* yet (e.g. I2C bridges).*/
return -ENODEV;
return -EPROBE_DEFER;
In general, how does that relate to i2c-bridge-drivers, as of_find_device_by_node supposedly only acts on platform-devices?
Also if that points to a disabled bridge (hdmi, etc) that would likely make it probe-defer indefinitly, as that device will never become available?
Maybe we could do something like of_device_is_available() which checks the status property of the node. So something like:
pdev = of_find_device_by_node(node); if (!pdev) { bool avail = of_device_is_available(node);
of_node_put(node);
/* if disabled if (!avail) return -ENODEV; else return -EPROBE_DEFER; } of_node_put(node);
Though I still do not understand how that should actually pick up on i2c devices at all.
Heiko