1/* SPDX-License-Identifier: MIT */
2/* Copyright © 2024 Intel Corporation */
3
4#ifndef __INTEL_HDCP_SHIM_H__
5#define __INTEL_HDCP_SHIM_H__
6
7#include <linux/types.h>
8
9#include <drm/intel/i915_hdcp_interface.h>
10
11enum transcoder;
12struct intel_connector;
13struct intel_digital_port;
14
15enum check_link_response {
16 HDCP_LINK_PROTECTED = 0,
17 HDCP_TOPOLOGY_CHANGE,
18 HDCP_LINK_INTEGRITY_FAILURE,
19 HDCP_REAUTH_REQUEST
20};
21
22/*
23 * This structure serves as a translation layer between the generic HDCP code
24 * and the bus-specific code. What that means is that HDCP over HDMI differs
25 * from HDCP over DP, so to account for these differences, we need to
26 * communicate with the receiver through this shim.
27 *
28 * For completeness, the 2 buses differ in the following ways:
29 * - DP AUX vs. DDC
30 * HDCP registers on the receiver are set via DP AUX for DP, and
31 * they are set via DDC for HDMI.
32 * - Receiver register offsets
33 * The offsets of the registers are different for DP vs. HDMI
34 * - Receiver register masks/offsets
35 * For instance, the ready bit for the KSV fifo is in a different
36 * place on DP vs HDMI
37 * - Receiver register names
38 * Seriously. In the DP spec, the 16-bit register containing
39 * downstream information is called BINFO, on HDMI it's called
40 * BSTATUS. To confuse matters further, DP has a BSTATUS register
41 * with a completely different definition.
42 * - KSV FIFO
43 * On HDMI, the ksv fifo is read all at once, whereas on DP it must
44 * be read 3 keys at a time
45 * - Aksv output
46 * Since Aksv is hidden in hardware, there's different procedures
47 * to send it over DP AUX vs DDC
48 */
49struct intel_hdcp_shim {
50 /* Outputs the transmitter's An and Aksv values to the receiver. */
51 int (*write_an_aksv)(struct intel_digital_port *dig_port, u8 *an);
52
53 /* Reads the receiver's key selection vector */
54 int (*read_bksv)(struct intel_digital_port *dig_port, u8 *bksv);
55
56 /*
57 * Reads BINFO from DP receivers and BSTATUS from HDMI receivers. The
58 * definitions are the same in the respective specs, but the names are
59 * different. Call it BSTATUS since that's the name the HDMI spec
60 * uses and it was there first.
61 */
62 int (*read_bstatus)(struct intel_digital_port *dig_port,
63 u8 *bstatus);
64
65 /* Determines whether a repeater is present downstream */
66 int (*repeater_present)(struct intel_digital_port *dig_port,
67 bool *repeater_present);
68
69 /* Reads the receiver's Ri' value */
70 int (*read_ri_prime)(struct intel_digital_port *dig_port, u8 *ri);
71
72 /* Determines if the receiver's KSV FIFO is ready for consumption */
73 int (*read_ksv_ready)(struct intel_digital_port *dig_port,
74 bool *ksv_ready);
75
76 /* Reads the ksv fifo for num_downstream devices */
77 int (*read_ksv_fifo)(struct intel_digital_port *dig_port,
78 int num_downstream, u8 *ksv_fifo);
79
80 /* Reads a 32-bit part of V' from the receiver */
81 int (*read_v_prime_part)(struct intel_digital_port *dig_port,
82 int i, u32 *part);
83
84 /* Enables HDCP signalling on the port */
85 int (*toggle_signalling)(struct intel_digital_port *dig_port,
86 enum transcoder cpu_transcoder,
87 bool enable);
88
89 /* Enable/Disable stream encryption on DP MST Transport Link */
90 int (*stream_encryption)(struct intel_connector *connector,
91 bool enable);
92
93 /* Ensures the link is still protected */
94 bool (*check_link)(struct intel_digital_port *dig_port,
95 struct intel_connector *connector);
96
97 /* Detects panel's hdcp capability. This is optional for HDMI. */
98 int (*hdcp_get_capability)(struct intel_digital_port *dig_port,
99 bool *hdcp_capable);
100
101 /* HDCP adaptation(DP/HDMI) required on the port */
102 enum hdcp_wired_protocol protocol;
103
104 /* Detects whether sink is HDCP2.2 capable */
105 int (*hdcp_2_2_get_capability)(struct intel_connector *connector,
106 bool *capable);
107
108 /* Write HDCP2.2 messages */
109 int (*write_2_2_msg)(struct intel_connector *connector,
110 void *buf, size_t size);
111
112 /* Read HDCP2.2 messages */
113 int (*read_2_2_msg)(struct intel_connector *connector,
114 u8 msg_id, void *buf, size_t size);
115
116 /*
117 * Implementation of DP HDCP2.2 Errata for the communication of stream
118 * type to Receivers. In DP HDCP2.2 Stream type is one of the input to
119 * the HDCP2.2 Cipher for En/De-Cryption. Not applicable for HDMI.
120 */
121 int (*config_stream_type)(struct intel_connector *connector,
122 bool is_repeater, u8 type);
123
124 /* Enable/Disable HDCP 2.2 stream encryption on DP MST Transport Link */
125 int (*stream_2_2_encryption)(struct intel_connector *connector,
126 bool enable);
127
128 /* HDCP2.2 Link Integrity Check */
129 int (*check_2_2_link)(struct intel_digital_port *dig_port,
130 struct intel_connector *connector);
131
132 /* HDCP remote sink cap */
133 int (*get_remote_hdcp_capability)(struct intel_connector *connector,
134 bool *hdcp_capable, bool *hdcp2_capable);
135};
136
137#endif /* __INTEL_HDCP_SHIM_H__ */
138