From: Hans Verkuil hans.verkuil@cisco.com
If aux->transfer == NULL, then just return without doing anything. In that case the function is likely called for a non-(e)DP connector.
This never happened for the i915 driver, but the nouveau and amdgpu drivers need this check.
The alternative would be to add this check in those drivers before every drm_dp_cec call, but it makes sense to check it in the drm_dp_cec functions to prevent a kernel oops.
Signed-off-by: Hans Verkuil hans.verkuil@cisco.com --- drivers/gpu/drm/drm_dp_cec.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+)
diff --git a/drivers/gpu/drm/drm_dp_cec.c b/drivers/gpu/drm/drm_dp_cec.c index 988513346e9c..1407b13a8d5d 100644 --- a/drivers/gpu/drm/drm_dp_cec.c +++ b/drivers/gpu/drm/drm_dp_cec.c @@ -238,6 +238,10 @@ void drm_dp_cec_irq(struct drm_dp_aux *aux) u8 cec_irq; int ret;
+ /* No transfer function was set, so not a DP connector */ + if (!aux->transfer) + return; + mutex_lock(&aux->cec.lock); if (!aux->cec.adap) goto unlock; @@ -293,6 +297,10 @@ void drm_dp_cec_set_edid(struct drm_dp_aux *aux, const struct edid *edid) unsigned int num_las = 1; u8 cap;
+ /* No transfer function was set, so not a DP connector */ + if (!aux->transfer) + return; + #ifndef CONFIG_MEDIA_CEC_RC /* * CEC_CAP_RC is part of CEC_CAP_DEFAULTS, but it is stripped by @@ -361,6 +369,10 @@ EXPORT_SYMBOL(drm_dp_cec_set_edid); */ void drm_dp_cec_unset_edid(struct drm_dp_aux *aux) { + /* No transfer function was set, so not a DP connector */ + if (!aux->transfer) + return; + cancel_delayed_work_sync(&aux->cec.unregister_work);
mutex_lock(&aux->cec.lock); @@ -404,6 +416,8 @@ void drm_dp_cec_register_connector(struct drm_dp_aux *aux, const char *name, struct device *parent) { WARN_ON(aux->cec.adap); + if (WARN_ON(!aux->transfer)) + return; aux->cec.name = name; aux->cec.parent = parent; INIT_DELAYED_WORK(&aux->cec.unregister_work,