xref: /linux/drivers/gpu/drm/amd/display/dc/link/protocols/link_hpd.c (revision d4a292c5f8e65d2784b703c67179f4f7d0c7846c)
1 /*
2  * Copyright 2022 Advanced Micro Devices, Inc.
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice shall be included in
12  * all copies or substantial portions of the Software.
13  *
14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
17  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20  * OTHER DEALINGS IN THE SOFTWARE.
21  *
22  * Authors: AMD
23  *
24  */
25 
26 /* FILE POLICY AND INTENDED USAGE:
27  *
28  * This file implements functions that manage basic HPD components such as gpio.
29  * It also provides wrapper functions to execute HPD related programming. This
30  * file only manages basic HPD functionality. It doesn't manage detection or
31  * feature or signal specific HPD behaviors.
32  */
33 #include "link_hpd.h"
34 #include "gpio_service_interface.h"
35 
link_get_hpd_state(struct dc_link * link)36 bool link_get_hpd_state(struct dc_link *link)
37 {
38 	if (link->link_enc)
39 		return link->link_enc->funcs->get_hpd_state(link->link_enc);
40 	else
41 		return false;
42 }
43 
link_enable_hpd(const struct dc_link * link)44 void link_enable_hpd(const struct dc_link *link)
45 {
46 	if (link->link_enc)
47 		link->link_enc->funcs->enable_hpd(link->link_enc);
48 }
49 
link_disable_hpd(const struct dc_link * link)50 void link_disable_hpd(const struct dc_link *link)
51 {
52 	if (link->link_enc)
53 		link->link_enc->funcs->disable_hpd(link->link_enc);
54 }
55 
link_enable_hpd_filter(struct dc_link * link,bool enable)56 void link_enable_hpd_filter(struct dc_link *link, bool enable)
57 {
58 	if (enable) {
59 		link->is_hpd_filter_disabled = false;
60 		program_hpd_filter(link);
61 	} else {
62 		link->is_hpd_filter_disabled = true;
63 		if (link->link_enc)
64 			link->link_enc->funcs->program_hpd_filter(link->link_enc, 0, 0);
65 	}
66 }
67 
program_hpd_filter(const struct dc_link * link)68 bool program_hpd_filter(const struct dc_link *link)
69 {
70 	int delay_on_connect_in_ms = 0;
71 	int delay_on_disconnect_in_ms = 0;
72 
73 	if (link->is_hpd_filter_disabled || !link->link_enc) {
74 		ASSERT(link->link_enc);
75 		return false;
76 	}
77 
78 	/* Verify feature is supported */
79 	switch (link->connector_signal) {
80 	case SIGNAL_TYPE_DVI_SINGLE_LINK:
81 	case SIGNAL_TYPE_DVI_DUAL_LINK:
82 	case SIGNAL_TYPE_HDMI_TYPE_A:
83 		/* Program hpd filter */
84 		delay_on_connect_in_ms = 500;
85 		delay_on_disconnect_in_ms = 100;
86 		break;
87 	case SIGNAL_TYPE_DISPLAY_PORT:
88 	case SIGNAL_TYPE_DISPLAY_PORT_MST:
89 		/* Program hpd filter to allow DP signal to settle */
90 		/* 500:	not able to detect MST <-> SST switch as HPD is low for
91 		 * only 100ms on DELL U2413
92 		 * 0: some passive dongle still show aux mode instead of i2c
93 		 * 20-50: not enough to hide bouncing HPD with passive dongle.
94 		 * also see intermittent i2c read issues.
95 		 */
96 		delay_on_connect_in_ms = 80;
97 		delay_on_disconnect_in_ms = 0;
98 		break;
99 	case SIGNAL_TYPE_LVDS:
100 	case SIGNAL_TYPE_EDP:
101 	default:
102 		/* Don't program hpd filter */
103 		return false;
104 	}
105 
106 	return link->link_enc->funcs->program_hpd_filter(link->link_enc, delay_on_connect_in_ms, delay_on_disconnect_in_ms);
107 }
108 
link_get_hpd_gpio(struct dc_bios * dcb,struct graphics_object_id link_id,struct gpio_service * gpio_service)109 struct gpio *link_get_hpd_gpio(struct dc_bios *dcb,
110 			  struct graphics_object_id link_id,
111 			  struct gpio_service *gpio_service)
112 {
113 	enum bp_result bp_result;
114 	struct graphics_object_hpd_info hpd_info;
115 	struct gpio_pin_info pin_info;
116 
117 	if (dcb->funcs->get_hpd_info(dcb, link_id, &hpd_info) != BP_RESULT_OK)
118 		return NULL;
119 
120 	bp_result = dcb->funcs->get_gpio_pin_info(dcb,
121 		hpd_info.hpd_int_gpio_uid, &pin_info);
122 
123 	if (bp_result != BP_RESULT_OK) {
124 		return NULL;
125 	}
126 
127 	return dal_gpio_service_create_irq(gpio_service,
128 					   pin_info.offset,
129 					   pin_info.mask);
130 }
131 
get_hpd_line(struct dc_link * link)132 enum hpd_source_id get_hpd_line(struct dc_link *link)
133 {
134 	struct gpio *hpd;
135 	enum hpd_source_id hpd_id;
136 
137 		hpd_id = HPD_SOURCEID_UNKNOWN;
138 
139 	/* Use GPIO path where supported, otherwise use hardware encoder path */
140 	if (link->ctx && link->ctx->dce_version <= DCN_VERSION_4_01) {
141 		hpd = link_get_hpd_gpio(link->ctx->dc_bios, link->link_id,
142 				   link->ctx->gpio_service);
143 	} else {
144 		hpd = NULL;
145 	}
146 
147 	if (hpd) {
148 		switch (dal_irq_get_source(hpd)) {
149 		case DC_IRQ_SOURCE_HPD1:
150 			hpd_id = HPD_SOURCEID1;
151 		break;
152 		case DC_IRQ_SOURCE_HPD2:
153 			hpd_id = HPD_SOURCEID2;
154 		break;
155 		case DC_IRQ_SOURCE_HPD3:
156 			hpd_id = HPD_SOURCEID3;
157 		break;
158 		case DC_IRQ_SOURCE_HPD4:
159 			hpd_id = HPD_SOURCEID4;
160 		break;
161 		case DC_IRQ_SOURCE_HPD5:
162 			hpd_id = HPD_SOURCEID5;
163 		break;
164 		case DC_IRQ_SOURCE_HPD6:
165 			hpd_id = HPD_SOURCEID6;
166 		break;
167 		default:
168 			BREAK_TO_DEBUGGER();
169 		break;
170 		}
171 
172 		dal_gpio_destroy_irq(&hpd);
173 	}
174 
175 	return hpd_id;
176 }
177