1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2013 Red Hat
4 * Author: Rob Clark <robdclark@gmail.com>
5 */
6
7 #include <linux/delay.h>
8 #include <linux/gpio/consumer.h>
9 #include <linux/pinctrl/consumer.h>
10
11 #include "msm_kms.h"
12 #include "hdmi.h"
13
msm_hdmi_phy_reset(struct hdmi * hdmi)14 static void msm_hdmi_phy_reset(struct hdmi *hdmi)
15 {
16 unsigned int val;
17
18 val = hdmi_read(hdmi, REG_HDMI_PHY_CTRL);
19
20 if (val & HDMI_PHY_CTRL_SW_RESET_LOW) {
21 /* pull low */
22 hdmi_write(hdmi, REG_HDMI_PHY_CTRL,
23 val & ~HDMI_PHY_CTRL_SW_RESET);
24 } else {
25 /* pull high */
26 hdmi_write(hdmi, REG_HDMI_PHY_CTRL,
27 val | HDMI_PHY_CTRL_SW_RESET);
28 }
29
30 if (val & HDMI_PHY_CTRL_SW_RESET_PLL_LOW) {
31 /* pull low */
32 hdmi_write(hdmi, REG_HDMI_PHY_CTRL,
33 val & ~HDMI_PHY_CTRL_SW_RESET_PLL);
34 } else {
35 /* pull high */
36 hdmi_write(hdmi, REG_HDMI_PHY_CTRL,
37 val | HDMI_PHY_CTRL_SW_RESET_PLL);
38 }
39
40 msleep(100);
41
42 if (val & HDMI_PHY_CTRL_SW_RESET_LOW) {
43 /* pull high */
44 hdmi_write(hdmi, REG_HDMI_PHY_CTRL,
45 val | HDMI_PHY_CTRL_SW_RESET);
46 } else {
47 /* pull low */
48 hdmi_write(hdmi, REG_HDMI_PHY_CTRL,
49 val & ~HDMI_PHY_CTRL_SW_RESET);
50 }
51
52 if (val & HDMI_PHY_CTRL_SW_RESET_PLL_LOW) {
53 /* pull high */
54 hdmi_write(hdmi, REG_HDMI_PHY_CTRL,
55 val | HDMI_PHY_CTRL_SW_RESET_PLL);
56 } else {
57 /* pull low */
58 hdmi_write(hdmi, REG_HDMI_PHY_CTRL,
59 val & ~HDMI_PHY_CTRL_SW_RESET_PLL);
60 }
61 }
62
msm_hdmi_hpd_enable(struct drm_bridge * bridge)63 void msm_hdmi_hpd_enable(struct drm_bridge *bridge)
64 {
65 struct hdmi_bridge *hdmi_bridge = to_hdmi_bridge(bridge);
66 struct hdmi *hdmi = hdmi_bridge->hdmi;
67 struct device *dev = &hdmi->pdev->dev;
68 uint32_t hpd_ctrl;
69 int ret;
70 unsigned long flags;
71
72 if (hdmi->hpd_gpiod)
73 gpiod_set_value_cansleep(hdmi->hpd_gpiod, 1);
74
75 ret = pm_runtime_resume_and_get(dev);
76 if (WARN_ON(ret))
77 return;
78
79 mutex_lock(&hdmi->state_mutex);
80 msm_hdmi_set_mode(hdmi, false);
81 msm_hdmi_phy_reset(hdmi);
82 msm_hdmi_set_mode(hdmi, true);
83
84 hdmi->hpd_enabled = true;
85 mutex_unlock(&hdmi->state_mutex);
86
87 hdmi_write(hdmi, REG_HDMI_USEC_REFTIMER, 0x0001001b);
88
89 /* enable HPD events: */
90 hdmi_write(hdmi, REG_HDMI_HPD_INT_CTRL,
91 HDMI_HPD_INT_CTRL_INT_CONNECT |
92 HDMI_HPD_INT_CTRL_INT_EN);
93
94 /* set timeout to 4.1ms (max) for hardware debounce */
95 spin_lock_irqsave(&hdmi->reg_lock, flags);
96 hpd_ctrl = hdmi_read(hdmi, REG_HDMI_HPD_CTRL);
97 hpd_ctrl |= HDMI_HPD_CTRL_TIMEOUT(0x1fff);
98
99 /* Toggle HPD circuit to trigger HPD sense */
100 hdmi_write(hdmi, REG_HDMI_HPD_CTRL,
101 ~HDMI_HPD_CTRL_ENABLE & hpd_ctrl);
102 hdmi_write(hdmi, REG_HDMI_HPD_CTRL,
103 HDMI_HPD_CTRL_ENABLE | hpd_ctrl);
104 spin_unlock_irqrestore(&hdmi->reg_lock, flags);
105 }
106
msm_hdmi_hpd_disable(struct drm_bridge * bridge)107 void msm_hdmi_hpd_disable(struct drm_bridge *bridge)
108 {
109 struct hdmi_bridge *hdmi_bridge = to_hdmi_bridge(bridge);
110 struct hdmi *hdmi = hdmi_bridge->hdmi;
111 struct device *dev = &hdmi->pdev->dev;
112
113 /* Disable HPD interrupt */
114 hdmi_write(hdmi, REG_HDMI_HPD_INT_CTRL, 0);
115
116 mutex_lock(&hdmi->state_mutex);
117 hdmi->hpd_enabled = false;
118 msm_hdmi_set_mode(hdmi, hdmi->power_on);
119 mutex_unlock(&hdmi->state_mutex);
120
121 pm_runtime_put(dev);
122 }
123
msm_hdmi_hpd_irq(struct drm_bridge * bridge)124 void msm_hdmi_hpd_irq(struct drm_bridge *bridge)
125 {
126 struct hdmi_bridge *hdmi_bridge = to_hdmi_bridge(bridge);
127 struct hdmi *hdmi = hdmi_bridge->hdmi;
128 uint32_t hpd_int_status, hpd_int_ctrl;
129
130 /* Process HPD: */
131 hpd_int_status = hdmi_read(hdmi, REG_HDMI_HPD_INT_STATUS);
132 hpd_int_ctrl = hdmi_read(hdmi, REG_HDMI_HPD_INT_CTRL);
133
134 if ((hpd_int_ctrl & HDMI_HPD_INT_CTRL_INT_EN) &&
135 (hpd_int_status & HDMI_HPD_INT_STATUS_INT)) {
136 bool detected = !!(hpd_int_status & HDMI_HPD_INT_STATUS_CABLE_DETECTED);
137
138 /* ack & disable (temporarily) HPD events: */
139 hdmi_write(hdmi, REG_HDMI_HPD_INT_CTRL,
140 HDMI_HPD_INT_CTRL_INT_ACK);
141
142 DBG("status=%04x, ctrl=%04x", hpd_int_status, hpd_int_ctrl);
143
144 /* detect disconnect if we are connected or visa versa: */
145 hpd_int_ctrl = HDMI_HPD_INT_CTRL_INT_EN;
146 if (!detected)
147 hpd_int_ctrl |= HDMI_HPD_INT_CTRL_INT_CONNECT;
148 hdmi_write(hdmi, REG_HDMI_HPD_INT_CTRL, hpd_int_ctrl);
149
150 queue_work(hdmi->workq, &hdmi_bridge->hpd_work);
151 }
152 }
153
detect_reg(struct hdmi * hdmi)154 static enum drm_connector_status detect_reg(struct hdmi *hdmi)
155 {
156 u32 hpd_int_status = 0;
157 int ret;
158
159 ret = pm_runtime_resume_and_get(&hdmi->pdev->dev);
160 if (ret)
161 goto out;
162
163 hpd_int_status = hdmi_read(hdmi, REG_HDMI_HPD_INT_STATUS);
164
165 out:
166 pm_runtime_put(&hdmi->pdev->dev);
167
168 return (hpd_int_status & HDMI_HPD_INT_STATUS_CABLE_DETECTED) ?
169 connector_status_connected : connector_status_disconnected;
170 }
171
172 #define HPD_GPIO_INDEX 2
detect_gpio(struct hdmi * hdmi)173 static enum drm_connector_status detect_gpio(struct hdmi *hdmi)
174 {
175 return gpiod_get_value(hdmi->hpd_gpiod) ?
176 connector_status_connected :
177 connector_status_disconnected;
178 }
179
180 enum drm_connector_status
msm_hdmi_bridge_detect(struct drm_bridge * bridge,struct drm_connector * connector)181 msm_hdmi_bridge_detect(struct drm_bridge *bridge, struct drm_connector *connector)
182 {
183 struct hdmi_bridge *hdmi_bridge = to_hdmi_bridge(bridge);
184 struct hdmi *hdmi = hdmi_bridge->hdmi;
185 enum drm_connector_status stat_gpio, stat_reg;
186 int retry = 20;
187
188 /*
189 * some platforms may not have hpd gpio. Rely only on the status
190 * provided by REG_HDMI_HPD_INT_STATUS in this case.
191 */
192 if (!hdmi->hpd_gpiod)
193 return detect_reg(hdmi);
194
195 do {
196 stat_gpio = detect_gpio(hdmi);
197 stat_reg = detect_reg(hdmi);
198
199 if (stat_gpio == stat_reg)
200 break;
201
202 mdelay(10);
203 } while (--retry);
204
205 /* the status we get from reading gpio seems to be more reliable,
206 * so trust that one the most if we didn't manage to get hdmi and
207 * gpio status to agree:
208 */
209 if (stat_gpio != stat_reg) {
210 DBG("HDMI_HPD_INT_STATUS tells us: %d", stat_reg);
211 DBG("hpd gpio tells us: %d", stat_gpio);
212 }
213
214 return stat_gpio;
215 }
216