diff options
| author | Jyri Sarha <jsarha@ti.com> | 2018-04-26 11:07:00 +0300 |
|---|---|---|
| committer | Thierry Reding <treding@nvidia.com> | 2018-05-18 12:22:06 +0300 |
| commit | 0c08754b59da5557532d946599854e6df28edc22 (patch) | |
| tree | f0ffc11a747bc9d185ec6d62bf8a0ec288cc1e49 /drivers/gpu/drm/drm_panel.c | |
| parent | 38992c57c9c8425dc9cb75efe6f9b9255ea627a0 (diff) | |
| download | linux-0c08754b59da5557532d946599854e6df28edc22.tar.xz | |
drm/panel: Add device_link from panel device to DRM device
Add device_link from panel device (supplier) to DRM device (consumer)
when drm_panel_attach() is called. This patch should protect the master
DRM driver if an attached panel driver unbinds while it is in use. The
device_link should make sure the DRM device is unbound before the panel
driver becomes unavailable.
The device_link is removed when drm_panel_detach() is called. The
drm_panel_detach() should be called by the consumer DRM driver, not the
panel driver, otherwise both drivers are racing to delete the same link.
Signed-off-by: Jyri Sarha <jsarha@ti.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: https://patchwork.freedesktop.org/patch/msgid/b53584fd988d045c13de22d81825395b0ae0aad7.1524727888.git.jsarha@ti.com
Diffstat (limited to 'drivers/gpu/drm/drm_panel.c')
| -rw-r--r-- | drivers/gpu/drm/drm_panel.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/drivers/gpu/drm/drm_panel.c b/drivers/gpu/drm/drm_panel.c index 71e407574276..965530a6f4cd 100644 --- a/drivers/gpu/drm/drm_panel.c +++ b/drivers/gpu/drm/drm_panel.c @@ -24,6 +24,7 @@ #include <linux/err.h> #include <linux/module.h> +#include <drm/drm_device.h> #include <drm/drm_crtc.h> #include <drm/drm_panel.h> @@ -104,6 +105,13 @@ int drm_panel_attach(struct drm_panel *panel, struct drm_connector *connector) if (panel->connector) return -EBUSY; + panel->link = device_link_add(connector->dev->dev, panel->dev, 0); + if (!panel->link) { + dev_err(panel->dev, "failed to link panel to %s\n", + dev_name(connector->dev->dev)); + return -EINVAL; + } + panel->connector = connector; panel->drm = connector->dev; @@ -125,6 +133,8 @@ EXPORT_SYMBOL(drm_panel_attach); */ int drm_panel_detach(struct drm_panel *panel) { + device_link_del(panel->link); + panel->connector = NULL; panel->drm = NULL; |