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| author | Ramalingam C <ramalingam.c@intel.com> | 2018-01-18 11:18:08 +0530 |
|---|---|---|
| committer | Sean Paul <seanpaul@chromium.org> | 2018-01-18 17:56:02 -0500 |
| commit | 49d85d034268ab9d9156ff6f81cc07d4caad03f6 (patch) | |
| tree | 5f5e5ace2fdfd293c5ad30f013fb638d1c56a36c /drivers/gpu/drm/i915/intel_hdcp.c | |
| parent | 24b42cbadb73e0b9ac67c2d619073b394bc146bd (diff) | |
| download | linux-stable-49d85d034268ab9d9156ff6f81cc07d4caad03f6.tar.gz linux-stable-49d85d034268ab9d9156ff6f81cc07d4caad03f6.tar.bz2 linux-stable-49d85d034268ab9d9156ff6f81cc07d4caad03f6.zip | |
drm/i915: Check for downstream topology errors
HDCP compliant Repeaters can support max of 127 devices and max
depth of 7 for downstream topology.
If these max limits are exceeded, repeater will set the
topology error flags MAX_CASCADE_EXCEEDED and/or MAX_DEVS_EXCEEDED
in Bstatus followed by asserting READY/CP_IRQ for HDCP transmitter.
This patch check for these error flags as soon as READY bit is asserted.
Signed-off-by: Ramalingam C <ramalingam.c@intel.com>
[seanpaul fixed checkpatch alignment issue]
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/1516254488-4971-5-git-send-email-ramalingam.c@intel.com
Diffstat (limited to 'drivers/gpu/drm/i915/intel_hdcp.c')
| -rw-r--r-- | drivers/gpu/drm/i915/intel_hdcp.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/intel_hdcp.c b/drivers/gpu/drm/i915/intel_hdcp.c index b50c03a3bfe6..db9527173a1e 100644 --- a/drivers/gpu/drm/i915/intel_hdcp.c +++ b/drivers/gpu/drm/i915/intel_hdcp.c @@ -160,6 +160,12 @@ int intel_hdcp_auth_downstream(struct intel_digital_port *intel_dig_port, if (ret) return ret; + if (DRM_HDCP_MAX_DEVICE_EXCEEDED(bstatus[0]) || + DRM_HDCP_MAX_CASCADE_EXCEEDED(bstatus[1])) { + DRM_ERROR("Max Topology Limit Exceeded\n"); + return -EPERM; + } + /* If there are no downstream devices, we're all done. */ num_downstream = DRM_HDCP_NUM_DOWNSTREAM(bstatus[0]); if (num_downstream == 0) { |