xref: /linux/drivers/gpu/drm/amd/display/dc/link/protocols/link_hpd.c (revision db5d28c0bfe566908719bec8e25443aabecbb802)
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 	uint32_t state = 0;
39 
40 	dal_gpio_lock_pin(link->hpd_gpio);
41 	dal_gpio_get_value(link->hpd_gpio, &state);
42 	dal_gpio_unlock_pin(link->hpd_gpio);
43 
44 	return state;
45 }
46 
link_enable_hpd(const struct dc_link * link)47 void link_enable_hpd(const struct dc_link *link)
48 {
49 	struct link_encoder *encoder = link->link_enc;
50 
51 	if (encoder != NULL && encoder->funcs->enable_hpd != NULL)
52 		encoder->funcs->enable_hpd(encoder);
53 }
54 
link_disable_hpd(const struct dc_link * link)55 void link_disable_hpd(const struct dc_link *link)
56 {
57 	struct link_encoder *encoder = link->link_enc;
58 
59 	if (encoder != NULL && encoder->funcs->enable_hpd != NULL)
60 		encoder->funcs->disable_hpd(encoder);
61 }
62 
link_enable_hpd_filter(struct dc_link * link,bool enable)63 void link_enable_hpd_filter(struct dc_link *link, bool enable)
64 {
65 	struct gpio *hpd;
66 
67 	if (enable) {
68 		link->is_hpd_filter_disabled = false;
69 		program_hpd_filter(link);
70 	} else {
71 		link->is_hpd_filter_disabled = true;
72 		/* Obtain HPD handle */
73 		hpd = link_get_hpd_gpio(link->ctx->dc_bios, link->link_id, link->ctx->gpio_service);
74 
75 		if (!hpd)
76 			return;
77 
78 		/* Setup HPD filtering */
79 		if (dal_gpio_open(hpd, GPIO_MODE_INTERRUPT) == GPIO_RESULT_OK) {
80 			struct gpio_hpd_config config;
81 
82 			config.delay_on_connect = 0;
83 			config.delay_on_disconnect = 0;
84 
85 			dal_irq_setup_hpd_filter(hpd, &config);
86 
87 			dal_gpio_close(hpd);
88 		} else {
89 			ASSERT_CRITICAL(false);
90 		}
91 		/* Release HPD handle */
92 		dal_gpio_destroy_irq(&hpd);
93 	}
94 }
95 
link_get_hpd_gpio(struct dc_bios * dcb,struct graphics_object_id link_id,struct gpio_service * gpio_service)96 struct gpio *link_get_hpd_gpio(struct dc_bios *dcb,
97 			  struct graphics_object_id link_id,
98 			  struct gpio_service *gpio_service)
99 {
100 	enum bp_result bp_result;
101 	struct graphics_object_hpd_info hpd_info;
102 	struct gpio_pin_info pin_info;
103 
104 	if (dcb->funcs->get_hpd_info(dcb, link_id, &hpd_info) != BP_RESULT_OK)
105 		return NULL;
106 
107 	bp_result = dcb->funcs->get_gpio_pin_info(dcb,
108 		hpd_info.hpd_int_gpio_uid, &pin_info);
109 
110 	if (bp_result != BP_RESULT_OK) {
111 		ASSERT(bp_result == BP_RESULT_NORECORD);
112 		return NULL;
113 	}
114 
115 	return dal_gpio_service_create_irq(gpio_service,
116 					   pin_info.offset,
117 					   pin_info.mask);
118 }
119 
query_hpd_status(struct dc_link * link,uint32_t * is_hpd_high)120 bool query_hpd_status(struct dc_link *link, uint32_t *is_hpd_high)
121 {
122 	struct gpio *hpd_pin = link_get_hpd_gpio(
123 			link->ctx->dc_bios, link->link_id,
124 			link->ctx->gpio_service);
125 	if (!hpd_pin)
126 		return false;
127 
128 	dal_gpio_open(hpd_pin, GPIO_MODE_INTERRUPT);
129 	dal_gpio_get_value(hpd_pin, is_hpd_high);
130 	dal_gpio_close(hpd_pin);
131 	dal_gpio_destroy_irq(&hpd_pin);
132 	return true;
133 }
134 
get_hpd_line(struct dc_link * link)135 enum hpd_source_id get_hpd_line(struct dc_link *link)
136 {
137 	struct gpio *hpd;
138 	enum hpd_source_id hpd_id;
139 
140 		hpd_id = HPD_SOURCEID_UNKNOWN;
141 
142 	hpd = link_get_hpd_gpio(link->ctx->dc_bios, link->link_id,
143 			   link->ctx->gpio_service);
144 
145 	if (hpd) {
146 		switch (dal_irq_get_source(hpd)) {
147 		case DC_IRQ_SOURCE_HPD1:
148 			hpd_id = HPD_SOURCEID1;
149 		break;
150 		case DC_IRQ_SOURCE_HPD2:
151 			hpd_id = HPD_SOURCEID2;
152 		break;
153 		case DC_IRQ_SOURCE_HPD3:
154 			hpd_id = HPD_SOURCEID3;
155 		break;
156 		case DC_IRQ_SOURCE_HPD4:
157 			hpd_id = HPD_SOURCEID4;
158 		break;
159 		case DC_IRQ_SOURCE_HPD5:
160 			hpd_id = HPD_SOURCEID5;
161 		break;
162 		case DC_IRQ_SOURCE_HPD6:
163 			hpd_id = HPD_SOURCEID6;
164 		break;
165 		default:
166 			BREAK_TO_DEBUGGER();
167 		break;
168 		}
169 
170 		dal_gpio_destroy_irq(&hpd);
171 	}
172 
173 	return hpd_id;
174 }
175 
program_hpd_filter(const struct dc_link * link)176 bool program_hpd_filter(const struct dc_link *link)
177 {
178 	bool result = false;
179 	struct gpio *hpd;
180 	int delay_on_connect_in_ms = 0;
181 	int delay_on_disconnect_in_ms = 0;
182 
183 	if (link->is_hpd_filter_disabled)
184 		return false;
185 	/* Verify feature is supported */
186 	switch (link->connector_signal) {
187 	case SIGNAL_TYPE_DVI_SINGLE_LINK:
188 	case SIGNAL_TYPE_DVI_DUAL_LINK:
189 	case SIGNAL_TYPE_HDMI_TYPE_A:
190 		/* Program hpd filter */
191 		delay_on_connect_in_ms = 500;
192 		delay_on_disconnect_in_ms = 100;
193 		break;
194 	case SIGNAL_TYPE_DISPLAY_PORT:
195 	case SIGNAL_TYPE_DISPLAY_PORT_MST:
196 		/* Program hpd filter to allow DP signal to settle */
197 		/* 500:	not able to detect MST <-> SST switch as HPD is low for
198 		 * only 100ms on DELL U2413
199 		 * 0: some passive dongle still show aux mode instead of i2c
200 		 * 20-50: not enough to hide bouncing HPD with passive dongle.
201 		 * also see intermittent i2c read issues.
202 		 */
203 		delay_on_connect_in_ms = 80;
204 		delay_on_disconnect_in_ms = 0;
205 		break;
206 	case SIGNAL_TYPE_LVDS:
207 	case SIGNAL_TYPE_EDP:
208 	default:
209 		/* Don't program hpd filter */
210 		return false;
211 	}
212 
213 	/* Obtain HPD handle */
214 	hpd = link_get_hpd_gpio(link->ctx->dc_bios, link->link_id,
215 			   link->ctx->gpio_service);
216 
217 	if (!hpd)
218 		return result;
219 
220 	/* Setup HPD filtering */
221 	if (dal_gpio_open(hpd, GPIO_MODE_INTERRUPT) == GPIO_RESULT_OK) {
222 		struct gpio_hpd_config config;
223 
224 		config.delay_on_connect = delay_on_connect_in_ms;
225 		config.delay_on_disconnect = delay_on_disconnect_in_ms;
226 
227 		dal_irq_setup_hpd_filter(hpd, &config);
228 
229 		dal_gpio_close(hpd);
230 
231 		result = true;
232 	} else {
233 		ASSERT_CRITICAL(false);
234 	}
235 
236 	/* Release HPD handle */
237 	dal_gpio_destroy_irq(&hpd);
238 
239 	return result;
240 }
241