1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * TPD12S015 HDMI ESD protection & level shifter chip driver
4 *
5 * Copyright (C) 2019 Texas Instruments Incorporated
6 *
7 * Based on the omapdrm-specific encoder-opa362 driver
8 *
9 * Copyright (C) 2013 Texas Instruments Incorporated
10 * Author: Tomi Valkeinen <tomi.valkeinen@ti.com>
11 */
12
13 #include <linux/delay.h>
14 #include <linux/gpio/consumer.h>
15 #include <linux/interrupt.h>
16 #include <linux/module.h>
17 #include <linux/mutex.h>
18 #include <linux/of.h>
19 #include <linux/of_graph.h>
20 #include <linux/platform_device.h>
21
22 #include <drm/drm_bridge.h>
23
24 struct tpd12s015_device {
25 struct drm_bridge bridge;
26
27 struct gpio_desc *ct_cp_hpd_gpio;
28 struct gpio_desc *ls_oe_gpio;
29 struct gpio_desc *hpd_gpio;
30 int hpd_irq;
31
32 struct drm_bridge *next_bridge;
33 };
34
to_tpd12s015(struct drm_bridge * bridge)35 static inline struct tpd12s015_device *to_tpd12s015(struct drm_bridge *bridge)
36 {
37 return container_of(bridge, struct tpd12s015_device, bridge);
38 }
39
tpd12s015_attach(struct drm_bridge * bridge,enum drm_bridge_attach_flags flags)40 static int tpd12s015_attach(struct drm_bridge *bridge,
41 enum drm_bridge_attach_flags flags)
42 {
43 struct tpd12s015_device *tpd = to_tpd12s015(bridge);
44 int ret;
45
46 if (!(flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR))
47 return -EINVAL;
48
49 ret = drm_bridge_attach(bridge->encoder, tpd->next_bridge,
50 bridge, flags);
51 if (ret < 0)
52 return ret;
53
54 gpiod_set_value_cansleep(tpd->ls_oe_gpio, 1);
55
56 /* DC-DC converter needs at max 300us to get to 90% of 5V. */
57 usleep_range(300, 1000);
58
59 return 0;
60 }
61
tpd12s015_detach(struct drm_bridge * bridge)62 static void tpd12s015_detach(struct drm_bridge *bridge)
63 {
64 struct tpd12s015_device *tpd = to_tpd12s015(bridge);
65
66 gpiod_set_value_cansleep(tpd->ls_oe_gpio, 0);
67 }
68
tpd12s015_detect(struct drm_bridge * bridge)69 static enum drm_connector_status tpd12s015_detect(struct drm_bridge *bridge)
70 {
71 struct tpd12s015_device *tpd = to_tpd12s015(bridge);
72
73 if (gpiod_get_value_cansleep(tpd->hpd_gpio))
74 return connector_status_connected;
75 else
76 return connector_status_disconnected;
77 }
78
tpd12s015_hpd_enable(struct drm_bridge * bridge)79 static void tpd12s015_hpd_enable(struct drm_bridge *bridge)
80 {
81 struct tpd12s015_device *tpd = to_tpd12s015(bridge);
82
83 gpiod_set_value_cansleep(tpd->ct_cp_hpd_gpio, 1);
84 }
85
tpd12s015_hpd_disable(struct drm_bridge * bridge)86 static void tpd12s015_hpd_disable(struct drm_bridge *bridge)
87 {
88 struct tpd12s015_device *tpd = to_tpd12s015(bridge);
89
90 gpiod_set_value_cansleep(tpd->ct_cp_hpd_gpio, 0);
91 }
92
93 static const struct drm_bridge_funcs tpd12s015_bridge_funcs = {
94 .attach = tpd12s015_attach,
95 .detach = tpd12s015_detach,
96 .detect = tpd12s015_detect,
97 .hpd_enable = tpd12s015_hpd_enable,
98 .hpd_disable = tpd12s015_hpd_disable,
99 };
100
tpd12s015_hpd_isr(int irq,void * data)101 static irqreturn_t tpd12s015_hpd_isr(int irq, void *data)
102 {
103 struct tpd12s015_device *tpd = data;
104 struct drm_bridge *bridge = &tpd->bridge;
105
106 drm_bridge_hpd_notify(bridge, tpd12s015_detect(bridge));
107
108 return IRQ_HANDLED;
109 }
110
tpd12s015_probe(struct platform_device * pdev)111 static int tpd12s015_probe(struct platform_device *pdev)
112 {
113 struct tpd12s015_device *tpd;
114 struct device_node *node;
115 struct gpio_desc *gpio;
116 int ret;
117
118 tpd = devm_kzalloc(&pdev->dev, sizeof(*tpd), GFP_KERNEL);
119 if (!tpd)
120 return -ENOMEM;
121
122 platform_set_drvdata(pdev, tpd);
123
124 tpd->bridge.funcs = &tpd12s015_bridge_funcs;
125 tpd->bridge.of_node = pdev->dev.of_node;
126 tpd->bridge.type = DRM_MODE_CONNECTOR_HDMIA;
127 tpd->bridge.ops = DRM_BRIDGE_OP_DETECT;
128
129 /* Get the next bridge, connected to port@1. */
130 node = of_graph_get_remote_node(pdev->dev.of_node, 1, -1);
131 if (!node)
132 return -ENODEV;
133
134 tpd->next_bridge = of_drm_find_bridge(node);
135 of_node_put(node);
136
137 if (!tpd->next_bridge)
138 return -EPROBE_DEFER;
139
140 /* Get the control and HPD GPIOs. */
141 gpio = devm_gpiod_get_index_optional(&pdev->dev, NULL, 0,
142 GPIOD_OUT_LOW);
143 if (IS_ERR(gpio))
144 return PTR_ERR(gpio);
145
146 tpd->ct_cp_hpd_gpio = gpio;
147
148 gpio = devm_gpiod_get_index_optional(&pdev->dev, NULL, 1,
149 GPIOD_OUT_LOW);
150 if (IS_ERR(gpio))
151 return PTR_ERR(gpio);
152
153 tpd->ls_oe_gpio = gpio;
154
155 gpio = devm_gpiod_get_index(&pdev->dev, NULL, 2, GPIOD_IN);
156 if (IS_ERR(gpio))
157 return PTR_ERR(gpio);
158
159 tpd->hpd_gpio = gpio;
160
161 /* Register the IRQ if the HPD GPIO is IRQ-capable. */
162 tpd->hpd_irq = gpiod_to_irq(tpd->hpd_gpio);
163 if (tpd->hpd_irq >= 0) {
164 ret = devm_request_threaded_irq(&pdev->dev, tpd->hpd_irq, NULL,
165 tpd12s015_hpd_isr,
166 IRQF_TRIGGER_RISING |
167 IRQF_TRIGGER_FALLING |
168 IRQF_ONESHOT,
169 "tpd12s015 hpd", tpd);
170 if (ret)
171 return ret;
172
173 tpd->bridge.ops |= DRM_BRIDGE_OP_HPD;
174 }
175
176 /* Register the DRM bridge. */
177 drm_bridge_add(&tpd->bridge);
178
179 return 0;
180 }
181
tpd12s015_remove(struct platform_device * pdev)182 static int tpd12s015_remove(struct platform_device *pdev)
183 {
184 struct tpd12s015_device *tpd = platform_get_drvdata(pdev);
185
186 drm_bridge_remove(&tpd->bridge);
187
188 return 0;
189 }
190
191 static const struct of_device_id tpd12s015_of_match[] = {
192 { .compatible = "ti,tpd12s015", },
193 {},
194 };
195
196 MODULE_DEVICE_TABLE(of, tpd12s015_of_match);
197
198 static struct platform_driver tpd12s015_driver = {
199 .probe = tpd12s015_probe,
200 .remove = tpd12s015_remove,
201 .driver = {
202 .name = "tpd12s015",
203 .of_match_table = tpd12s015_of_match,
204 },
205 };
206
207 module_platform_driver(tpd12s015_driver);
208
209 MODULE_AUTHOR("Tomi Valkeinen <tomi.valkeinen@ti.com>");
210 MODULE_DESCRIPTION("TPD12S015 HDMI level shifter and ESD protection driver");
211 MODULE_LICENSE("GPL");
212