[PATCH AUTOSEL 5.7 13/53] drm: mcde: Fix display initialization problem

Sasha Levin
2020-07-02T01:23:25Z

From: Linus Walleij <linus.walleij@linaro.org>

[ Upstream commit b984b6d8b52372b98cce0a6ff6c2787f50665b87 ]

The following bug appeared in the MCDE driver/display
initialization during the recent merge window.

First the place we call drm_fbdev_generic_setup() in the
wrong place: this needs to be called AFTER calling
drm_dev_register() else we get this splat:

------------[ cut here ]------------
WARNING: CPU: 0 PID: 1 at ../drivers/gpu/drm/drm_fb_helper.c:2198 drm_fbdev_generic_setup+0x164/0x1a8
mcde a0350000.mcde: Device has not been registered.
Modules linked in:
Hardware name: ST-Ericsson Ux5x0 platform (Device Tree Support)
[<c010e704>] (unwind_backtrace) from [<c010a86c>] (show_stack+0x10/0x14)
[<c010a86c>] (show_stack) from [<c0414f38>] (dump_stack+0x9c/0xb0)
[<c0414f38>] (dump_stack) from [<c0121c8c>] (__warn+0xb8/0xd0)
[<c0121c8c>] (__warn) from [<c0121d18>] (warn_slowpath_fmt+0x74/0xb8)
[<c0121d18>] (warn_slowpath_fmt) from [<c04b154c>] (drm_fbdev_generic_setup+0x164/0x1a8)
[<c04b154c>] (drm_fbdev_generic_setup) from [<c04ed278>] (mcde_drm_bind+0xc4/0x160)
[<c04ed278>] (mcde_drm_bind) from [<c04f06b8>] (try_to_bring_up_master+0x15c/0x1a4)
(...)

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200613223027.4189309-1-linus.walleij@linaro.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/gpu/drm/mcde/mcde_drv.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/mcde/mcde_drv.c b/drivers/gpu/drm/mcde/mcde_drv.c
index f28cb7a576ba4..1e7c5aa4d5e62 100644
--- a/drivers/gpu/drm/mcde/mcde_drv.c
+++ b/drivers/gpu/drm/mcde/mcde_drv.c
@@ -208,7 +208,6 @@ static int mcde_modeset_init(struct drm_device *drm)

drm_mode_config_reset(drm);
drm_kms_helper_poll_init(drm);
- drm_fbdev_generic_setup(drm, 32);

return 0;

@@ -275,6 +274,8 @@ static int mcde_drm_bind(struct device *dev)
if (ret < 0)
goto unbind;

+ drm_fbdev_generic_setup(drm, 32);
+
return 0;

unbind:
--
2.25.1