[PATCH v8 02/17] drm/i915: Clear the repeater bit on HDCP disable - Linux-stable-mirror

18 Aug 2020

From: Sean Paul seanpaul@chromium.org
On HDCP disable, clear the repeater bit. This ensures if we connect a
non-repeater sink after a repeater, the bit is in the state we expect.
Fixes: ee5e5e7a5e0f (drm/i915: Add HDCP framework + base implementation)
Cc: Chris Wilson chris@chris-wilson.co.uk
Cc: Ramalingam C ramalingam.c@intel.com
Cc: Daniel Vetter daniel.vetter@ffwll.ch
Cc: Sean Paul seanpaul@chromium.org
Cc: Jani Nikula jani.nikula@linux.intel.com
Cc: Joonas Lahtinen joonas.lahtinen@linux.intel.com
Cc: Rodrigo Vivi rodrigo.vivi@intel.com
Cc: intel-gfx@lists.freedesktop.org
Cc: stable@vger.kernel.org # v4.17+
Reviewed-by: Ramalingam C ramalingam.c@intel.com
Signed-off-by: Sean Paul seanpaul@chromium.org
Link: https://patchwork.freedesktop.org/patch/msgid/20191212190230.188505-3-sean@p... #v2
Link: https://patchwork.freedesktop.org/patch/msgid/20200117193103.156821-3-sean@p... #v3
Link: https://patchwork.freedesktop.org/patch/msgid/20200218220242.107265-3-sean@p... #v4
Link: https://patchwork.freedesktop.org/patch/msgid/20200305201236.152307-3-sean@p... #v5
Link: https://patchwork.freedesktop.org/patch/msgid/20200429195502.39919-3-sean@po... #v6
Link: https://patchwork.freedesktop.org/patch/msgid/20200623155907.22961-3-sean@po... #v7
Changes in v2:
-Added to the set
Changes in v3:
-None
  I had previously agreed that clearing the rep_ctl bits on enable would
  also be a good idea. However when I committed that idea to code, it
  didn't look right. So let's rely on enables and disables being paired
  and everything outside of that will be considered a bug
Changes in v4:
-s/I915_(READ|WRITE)/intel_de_(read|write)/
Changes in v5:
-None
Changes in v6:
-None
Changes in v7:
-None
Changes in v8:
-None
---
 drivers/gpu/drm/i915/display/intel_hdcp.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/gpu/drm/i915/display/intel_hdcp.c b/drivers/gpu/drm/i915/display/intel_hdcp.c
index 6189b7583277..1a0d49af2a08 100644
--- a/drivers/gpu/drm/i915/display/intel_hdcp.c
+++ b/drivers/gpu/drm/i915/display/intel_hdcp.c
@@ -795,6 +795,7 @@ static int _intel_hdcp_disable(struct intel_connector *connector)
    struct intel_hdcp *hdcp = &connector->hdcp;
    enum port port = dig_port->base.port;
    enum transcoder cpu_transcoder = hdcp->cpu_transcoder;
+	u32 repeater_ctl;
    int ret;
drm_dbg_kms(&dev_priv->drm, "[%s:%d] HDCP is being disabled...\n",
@@ -810,6 +811,11 @@ static int _intel_hdcp_disable(struct intel_connector *connector)
    	return -ETIMEDOUT;
    }
+	repeater_ctl = intel_hdcp_get_repeater_ctl(dev_priv, cpu_transcoder,
+						   port);
+	intel_de_write(dev_priv, HDCP_REP_CTL,
+		       intel_de_read(dev_priv, HDCP_REP_CTL) & ~repeater_ctl);
+
    ret = hdcp->shim->toggle_signalling(dig_port, false);
    if (ret) {
    	drm_err(&dev_priv->drm, "Failed to disable HDCP signalling\n");
-- 
Sean Paul, Software Engineer, Google / Chromium OS


    