Commit 32097060 authored Feb 15, 2019 by Ramalingam C Committed by Daniel Vetter Feb 15, 2019

drm: helper functions for hdcp2 seq_num to from u32



Library functions for endianness are aligned for 16/32/64 bits.
But hdcp sequence numbers are 24bits(big endian).
So for their conversion to and from u32 helper functions are developed.

v2:
  Comment is updated. [Daniel]
  Reviewed-by Uma.

Signed-off-by: Ramalingam C <ramalingam.c@intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Uma Shankar <uma.shankar@intel.com>
Acked-by: Dave Airlie <airlied@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/1550219730-17734-10-git-send-email-ramalingam.c@intel.com

parent 1bf7cb4d

include/drm/drm_hdcp.h

+18 −0

Original line number	Diff line number	Diff line
		@@ -250,4 +250,22 @@ 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))

		/*
		* Helper functions to convert 24bit big endian hdcp sequence number to
		* host format and back
		*/
		static inline
		u32 drm_hdcp2_seq_num_to_u32(u8 seq_num[HDCP_2_2_SEQ_NUM_LEN])
		{
		return (u32)(seq_num[2] \| seq_num[1] << 8 \| seq_num[0] << 16);
		}

		static inline
		void drm_hdcp2_u32_to_seq_num(u8 seq_num[HDCP_2_2_SEQ_NUM_LEN], u32 val)
		{
		seq_num[0] = val >> 16;
		seq_num[1] = val >> 8;
		seq_num[2] = val;
		}

		#endif

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