[Intel-gfx] [PATCH v14 29/33] misc/mei/hdcp: Verify M_prime

[Winkler, Tomas]

> 
> 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.
> v9:
>   renamed func as mei_hdcp_* [Tomas]
>   Inline function is defined for DDI index [Tomas]
> v10:
>   K-Doc fix. [Tomas]
> 
> Signed-off-by: Ramalingam C <ramalingam.c at intel.com>
> Reviewed-by: Uma Shankar <uma.shankar at intel.com>
> Acked-by: Tomas Winkler <tomas.winkler at intel.com>
> ---


> +
> +	verify_mprime_in.k = __swab16(data->k);
> +
                 cpu_to_be16(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;