drm/dp: add a hw mutex around the transfer functions. (v2)

This should avoid races between connector probing and HPD
irqs in the future, currently mode_config.mutex blocks this
possibility.

Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 4 insertions, 3 deletions

diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h
index 488b41635dec..a21568bf1514 100644
--- a/include/drm/drm_dp_helper.h
+++ b/include/drm/drm_dp_helper.h
@@ -514,6 +514,7 @@ struct drm_dp_aux_msg {
  * @name: user-visible name of this AUX channel and the I2C-over-AUX adapter
  * @ddc: I2C adapter that can be used for I2C-over-AUX communication
  * @dev: pointer to struct device that is the parent for this AUX channel
+ * @hw_mutex: internal mutex used for locking transfers
  * @transfer: transfers a message representing a single AUX transaction
  *
  * The .dev field should be set to a pointer to the device that implements
@@ -546,7 +547,7 @@ struct drm_dp_aux {
         const char *name;
         struct i2c_adapter ddc;
         struct device *dev;
-
+        struct mutex hw_mutex;
         ssize_t (*transfer)(struct drm_dp_aux *aux,
                             struct drm_dp_aux_msg *msg);
 };
@@ -605,7 +606,7 @@ int drm_dp_link_probe(struct drm_dp_aux *aux, struct drm_dp_link *link);
 int drm_dp_link_power_up(struct drm_dp_aux *aux, struct drm_dp_link *link);
 int drm_dp_link_configure(struct drm_dp_aux *aux, struct drm_dp_link *link);
 
-int drm_dp_aux_register_i2c_bus(struct drm_dp_aux *aux);
-void drm_dp_aux_unregister_i2c_bus(struct drm_dp_aux *aux);
+int drm_dp_aux_register(struct drm_dp_aux *aux);
+void drm_dp_aux_unregister(struct drm_dp_aux *aux);
 
 #endif /* _DRM_DP_HELPER_H_ */