diff mbox

[v4,16/41] misc/mei/hdcp: Verify M_prime

Message ID 1526907240-17639-17-git-send-email-ramalingam.c@intel.com (mailing list archive)
State New, archived
Headers show

Commit Message

Ramalingam C May 21, 2018, 12:53 p.m. UTC
Request to ME to verify the M_Prime received from the HDCP sink.

ME FW will calculate the M and compare with M_prime received
as part of RepeaterAuth_Stream_Ready, which is HDCP2.2 protocol msg.

On successful completion of this stage, downstream propagation of
the stream management info is completed.

v2:
  Rebased.
v3:
  cldev is passed as first parameter [Tomas]
  Redundant comments and cast are removed [Tomas]
v4:
  %zd for ssize_t [Alexander]
  %s/return -1/return -EIO [Alexander]
  endianness conversion func is moved to drm_hdcp.h [Uma]

Signed-off-by: Ramalingam C <ramalingam.c@intel.com>
---
 drivers/misc/mei/hdcp/mei_hdcp.c | 68 ++++++++++++++++++++++++++++++++++++++++
 include/drm/drm_hdcp.h           | 15 +++++++++
 include/linux/mei_hdcp.h         |  8 +++++
 3 files changed, 91 insertions(+)
diff mbox

Patch

diff --git a/drivers/misc/mei/hdcp/mei_hdcp.c b/drivers/misc/mei/hdcp/mei_hdcp.c
index d729348f5ae2..32a039d46738 100644
--- a/drivers/misc/mei/hdcp/mei_hdcp.c
+++ b/drivers/misc/mei/hdcp/mei_hdcp.c
@@ -559,6 +559,74 @@  mei_repeater_check_flow_prepare_ack(struct mei_cl_device *cldev,
 }
 EXPORT_SYMBOL(mei_repeater_check_flow_prepare_ack);
 
+/*
+ * mei_verify_mprime:
+ *	Function to verify mprime.
+ *
+ * cldev		: Pointer for mei client device
+ * data			: Intel HW specific Data
+ * stream_ready		: pointer for RepeaterAuth_Stream_Ready message.
+ *
+ * Returns 0 on Success, <0 on Failure
+ */
+int mei_verify_mprime(struct mei_cl_device *cldev, struct mei_hdcp_data *data,
+		      struct hdcp2_rep_stream_ready *stream_ready)
+{
+	struct wired_cmd_repeater_auth_stream_req_in
+					verify_mprime_in = { { 0 } };
+	struct wired_cmd_repeater_auth_stream_req_out
+					verify_mprime_out = { { 0 } };
+	struct device *dev;
+	ssize_t byte;
+
+	if (!stream_ready || !data)
+		return -EINVAL;
+
+	dev = &cldev->dev;
+
+	verify_mprime_in.header.api_version = HDCP_API_VERSION;
+	verify_mprime_in.header.command_id = WIRED_REPEATER_AUTH_STREAM_REQ;
+	verify_mprime_in.header.status = ME_HDCP_STATUS_SUCCESS;
+	verify_mprime_in.header.buffer_len =
+			WIRED_CMD_BUF_LEN_REPEATER_AUTH_STREAM_REQ_MIN_IN;
+
+	verify_mprime_in.port.integrated_port_type = data->port_type;
+	verify_mprime_in.port.physical_port = data->port;
+
+	memcpy(verify_mprime_in.m_prime, stream_ready->m_prime,
+	       HDCP_2_2_MPRIME_LEN);
+	reverse_endianness((u8 *)&verify_mprime_in.seq_num_m,
+			   HDCP_2_2_SEQ_NUM_LEN, (u8 *)&data->seq_num_m);
+	memcpy(verify_mprime_in.streams, data->streams,
+	       (data->k * sizeof(struct hdcp2_streamid_type)));
+
+	verify_mprime_in.k = __swab16(data->k);
+
+	byte = mei_cldev_send(cldev, (u8 *)&verify_mprime_in,
+			      sizeof(verify_mprime_in));
+	if (byte < 0) {
+		dev_dbg(dev, "mei_cldev_send failed. %zd\n", byte);
+		return byte;
+	}
+
+	byte = mei_cldev_recv(cldev, (u8 *)&verify_mprime_out,
+			      sizeof(verify_mprime_out));
+	if (byte < 0) {
+		dev_dbg(dev, "mei_cldev_recv failed. %zd\n", byte);
+		return byte;
+	}
+
+	if (verify_mprime_out.header.status != ME_HDCP_STATUS_SUCCESS) {
+		dev_dbg(dev, "ME cmd 0x%08X failed. status: 0x%X\n",
+			WIRED_REPEATER_AUTH_STREAM_REQ,
+			verify_mprime_out.header.status);
+		return -EIO;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL(mei_verify_mprime);
+
 static void
 mei_cldev_state_notify_clients(struct mei_cl_device *cldev, bool enabled)
 {
diff --git a/include/drm/drm_hdcp.h b/include/drm/drm_hdcp.h
index efd493306130..6ce9f9d432dc 100644
--- a/include/drm/drm_hdcp.h
+++ b/include/drm/drm_hdcp.h
@@ -247,4 +247,19 @@  struct hdcp2_dp_errata_stream_type {
 #define HDCP_2_2_HDMI_RXSTATUS_READY(x)		(x & BIT(2))
 #define HDCP_2_2_HDMI_RXSTATUS_REAUTH_REQ(x)	(x & BIT(3))
 
+/*
+ * Library functions for endianness are aligned for 16/32/64 bits.
+ * But hdcp sequence numbers are 24bits. So for their Byte swapping,
+ * a conversion function is developed.
+ */
+static inline void reverse_endianness(u8 *dest, size_t sz, u8 *src)
+{
+	u32 index;
+
+	if (!sz || sz > sizeof(u32))
+		return;
+	for (index = 0; index < sz; index++)
+		dest[sz - index - 1] = src[index];
+}
+
 #endif
diff --git a/include/linux/mei_hdcp.h b/include/linux/mei_hdcp.h
index 2713cf321a58..e7e1e86c6663 100644
--- a/include/linux/mei_hdcp.h
+++ b/include/linux/mei_hdcp.h
@@ -135,6 +135,8 @@  mei_repeater_check_flow_prepare_ack(struct mei_cl_device *cldev,
 				    struct hdcp2_rep_send_receiverid_list
 							*rep_topology,
 				    struct hdcp2_rep_send_ack *rep_send_ack);
+int mei_verify_mprime(struct mei_cl_device *cldev, struct mei_hdcp_data *data,
+		      struct hdcp2_rep_stream_ready *stream_ready);
 #else
 static inline int mei_cldev_register_notify(struct notifier_block *nb)
 {
@@ -206,5 +208,11 @@  mei_repeater_check_flow_prepare_ack(struct mei_cl_device *cldev,
 {
 	return -ENODEV;
 }
+static inline
+int mei_verify_mprime(struct mei_cl_device *cldev, struct mei_hdcp_data *data,
+		      struct hdcp2_rep_stream_ready *stream_ready)
+{
+	return -ENODEV;
+}
 #endif /* IS_ENABLED(CONFIG_INTEL_MEI_HDCP) */
 #endif /* defined (_LINUX_MEI_HDCP_H) */