[PATCH v10 33/40] misc/mei/hdcp: Verify M_prime

Ramalingam C
2019-01-31T06:59:49Z

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]
v5: Rebased.
v6:
Collected the Rb-ed by.
Rebasing.
v7:
Adjust to the new mei interface.
Fix for Kdoc.
v8:
K-Doc addition. [Tomas]
drm_hdcp2_u32_to_seq_num() is used for u32 to seq_num.

Signed-off-by: Ramalingam C <ramalingam.c@intel.com>
Reviewed-by: Uma Shankar <uma.shankar@intel.com>
---
drivers/misc/mei/hdcp/mei_hdcp.c | 66 +++++++++++++++++++++++++++++++++++++++-
1 file changed, 65 insertions(+), 1 deletion(-)

diff --git a/drivers/misc/mei/hdcp/mei_hdcp.c b/drivers/misc/mei/hdcp/mei_hdcp.c
index c157c18371b4..91f7b08d1df1 100644
--- a/drivers/misc/mei/hdcp/mei_hdcp.c
+++ b/drivers/misc/mei/hdcp/mei_hdcp.c
@@ -523,6 +523,70 @@ mei_repeater_check_flow_prepare_ack(struct device *dev,
return 0;
}

+/**
+ * mei_verify_mprime() - Verify mprime.
+ * @dev: device corresponding to the mei_cl_device
+ * @hdcp_data: Intel HW specific hdcp data
+ * @stream_ready: RepeaterAuth_Stream_Ready msg for ME FW verification.
+ *
+ * Return: 0 on Success, <0 on Failure
+ */
+static int mei_verify_mprime(struct device *dev, struct hdcp_port_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 mei_cl_device *cldev;
+ ssize_t byte;
+
+ if (!dev || !stream_ready || !data)
+ return -EINVAL;
+
+ cldev = to_mei_cl_device(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 = (u8)GET_MEI_DDI_INDEX(data->port);
+
+ memcpy(verify_mprime_in.m_prime, stream_ready->m_prime,
+ HDCP_2_2_MPRIME_LEN);
+ drm_hdcp2_u32_to_seq_num(verify_mprime_in.seq_num_m, 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;
+}
+
static __attribute__((unused))
struct i915_hdcp_component_ops mei_hdcp_ops = {
.owner = THIS_MODULE,
@@ -534,7 +598,7 @@ struct i915_hdcp_component_ops mei_hdcp_ops = {
.verify_lprime = mei_verify_lprime,
.get_session_key = mei_get_session_key,
.repeater_check_flow_prepare_ack = mei_repeater_check_flow_prepare_ack,
- .verify_mprime = NULL,
+ .verify_mprime = mei_verify_mprime,
.enable_hdcp_authentication = NULL,
.close_hdcp_session = NULL,
};
--
2.7.4