diff options
| author | Jammy Huang <jammy_huang@aspeedtech.com> | 2023-06-01 02:48:47 +0200 |
|---|---|---|
| committer | Thomas Zimmermann <tzimmermann@suse.de> | 2023-06-01 10:40:38 +0200 |
| commit | 3692ababa322b4d9ffbd973865bc88018e896fcd (patch) | |
| tree | 8a2b250913d1a8202942038b112844c82205836c /drivers/gpu/drm/ast/ast_mode.c | |
| parent | drm/ast: Fix long time waiting on s3/s4 resume (diff) | |
| download | linux-3692ababa322b4d9ffbd973865bc88018e896fcd.tar.xz linux-3692ababa322b4d9ffbd973865bc88018e896fcd.zip | |
drm/ast: Fix modeset failed on DisplayPort
If we switch display and update cursor together, it could lead to
modeset failed because of concurrent access to IO registers.
Add lock protection in DP's edid access to avoid this problem.
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Jammy Huang <jammy_huang@aspeedtech.com>
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20230601004847.1115-1-jammy_huang@aspeedtech.com
Diffstat (limited to 'drivers/gpu/drm/ast/ast_mode.c')
| -rw-r--r-- | drivers/gpu/drm/ast/ast_mode.c | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/drivers/gpu/drm/ast/ast_mode.c b/drivers/gpu/drm/ast/ast_mode.c index 36374828f6c8..b3c670af6ef2 100644 --- a/drivers/gpu/drm/ast/ast_mode.c +++ b/drivers/gpu/drm/ast/ast_mode.c @@ -1647,6 +1647,8 @@ static int ast_dp501_output_init(struct ast_device *ast) static int ast_astdp_connector_helper_get_modes(struct drm_connector *connector) { void *edid; + struct drm_device *dev = connector->dev; + struct ast_device *ast = to_ast_device(dev); int succ; int count; @@ -1655,9 +1657,17 @@ static int ast_astdp_connector_helper_get_modes(struct drm_connector *connector) if (!edid) goto err_drm_connector_update_edid_property; + /* + * Protect access to I/O registers from concurrent modesetting + * by acquiring the I/O-register lock. + */ + mutex_lock(&ast->ioregs_lock); + succ = ast_astdp_read_edid(connector->dev, edid); if (succ < 0) - goto err_kfree; + goto err_mutex_unlock; + + mutex_unlock(&ast->ioregs_lock); drm_connector_update_edid_property(connector, edid); count = drm_add_edid_modes(connector, edid); @@ -1665,7 +1675,8 @@ static int ast_astdp_connector_helper_get_modes(struct drm_connector *connector) return count; -err_kfree: +err_mutex_unlock: + mutex_unlock(&ast->ioregs_lock); kfree(edid); err_drm_connector_update_edid_property: drm_connector_update_edid_property(connector, NULL); |