xref: /openbmc/linux/drivers/gpu/drm/tegra/output.c (revision a8da474e)
1 /*
2  * Copyright (C) 2012 Avionic Design GmbH
3  * Copyright (C) 2012 NVIDIA CORPORATION.  All rights reserved.
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License version 2 as
7  * published by the Free Software Foundation.
8  */
9 
10 #include <drm/drm_atomic_helper.h>
11 #include <drm/drm_panel.h>
12 #include "drm.h"
13 
14 int tegra_output_connector_get_modes(struct drm_connector *connector)
15 {
16 	struct tegra_output *output = connector_to_output(connector);
17 	struct edid *edid = NULL;
18 	int err = 0;
19 
20 	/*
21 	 * If the panel provides one or more modes, use them exclusively and
22 	 * ignore any other means of obtaining a mode.
23 	 */
24 	if (output->panel) {
25 		err = output->panel->funcs->get_modes(output->panel);
26 		if (err > 0)
27 			return err;
28 	}
29 
30 	if (output->edid)
31 		edid = kmemdup(output->edid, sizeof(*edid), GFP_KERNEL);
32 	else if (output->ddc)
33 		edid = drm_get_edid(connector, output->ddc);
34 
35 	drm_mode_connector_update_edid_property(connector, edid);
36 
37 	if (edid) {
38 		err = drm_add_edid_modes(connector, edid);
39 		kfree(edid);
40 	}
41 
42 	return err;
43 }
44 
45 struct drm_encoder *
46 tegra_output_connector_best_encoder(struct drm_connector *connector)
47 {
48 	struct tegra_output *output = connector_to_output(connector);
49 
50 	return &output->encoder;
51 }
52 
53 enum drm_connector_status
54 tegra_output_connector_detect(struct drm_connector *connector, bool force)
55 {
56 	struct tegra_output *output = connector_to_output(connector);
57 	enum drm_connector_status status = connector_status_unknown;
58 
59 	if (gpio_is_valid(output->hpd_gpio)) {
60 		if (output->hpd_gpio_flags & OF_GPIO_ACTIVE_LOW) {
61 			if (gpio_get_value(output->hpd_gpio) != 0)
62 				status = connector_status_disconnected;
63 			else
64 				status = connector_status_connected;
65 		} else {
66 			if (gpio_get_value(output->hpd_gpio) == 0)
67 				status = connector_status_disconnected;
68 			else
69 				status = connector_status_connected;
70 		}
71 	} else {
72 		if (!output->panel)
73 			status = connector_status_disconnected;
74 		else
75 			status = connector_status_connected;
76 	}
77 
78 	return status;
79 }
80 
81 void tegra_output_connector_destroy(struct drm_connector *connector)
82 {
83 	drm_connector_unregister(connector);
84 	drm_connector_cleanup(connector);
85 }
86 
87 void tegra_output_encoder_destroy(struct drm_encoder *encoder)
88 {
89 	drm_encoder_cleanup(encoder);
90 }
91 
92 static irqreturn_t hpd_irq(int irq, void *data)
93 {
94 	struct tegra_output *output = data;
95 
96 	if (output->connector.dev)
97 		drm_helper_hpd_irq_event(output->connector.dev);
98 
99 	return IRQ_HANDLED;
100 }
101 
102 int tegra_output_probe(struct tegra_output *output)
103 {
104 	struct device_node *ddc, *panel;
105 	int err, size;
106 
107 	if (!output->of_node)
108 		output->of_node = output->dev->of_node;
109 
110 	panel = of_parse_phandle(output->of_node, "nvidia,panel", 0);
111 	if (panel) {
112 		output->panel = of_drm_find_panel(panel);
113 		if (!output->panel)
114 			return -EPROBE_DEFER;
115 
116 		of_node_put(panel);
117 	}
118 
119 	output->edid = of_get_property(output->of_node, "nvidia,edid", &size);
120 
121 	ddc = of_parse_phandle(output->of_node, "nvidia,ddc-i2c-bus", 0);
122 	if (ddc) {
123 		output->ddc = of_find_i2c_adapter_by_node(ddc);
124 		if (!output->ddc) {
125 			err = -EPROBE_DEFER;
126 			of_node_put(ddc);
127 			return err;
128 		}
129 
130 		of_node_put(ddc);
131 	}
132 
133 	output->hpd_gpio = of_get_named_gpio_flags(output->of_node,
134 						   "nvidia,hpd-gpio", 0,
135 						   &output->hpd_gpio_flags);
136 	if (gpio_is_valid(output->hpd_gpio)) {
137 		unsigned long flags;
138 
139 		err = gpio_request_one(output->hpd_gpio, GPIOF_DIR_IN,
140 				       "HDMI hotplug detect");
141 		if (err < 0) {
142 			dev_err(output->dev, "gpio_request_one(): %d\n", err);
143 			return err;
144 		}
145 
146 		err = gpio_to_irq(output->hpd_gpio);
147 		if (err < 0) {
148 			dev_err(output->dev, "gpio_to_irq(): %d\n", err);
149 			gpio_free(output->hpd_gpio);
150 			return err;
151 		}
152 
153 		output->hpd_irq = err;
154 
155 		flags = IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING |
156 			IRQF_ONESHOT;
157 
158 		err = request_threaded_irq(output->hpd_irq, NULL, hpd_irq,
159 					   flags, "hpd", output);
160 		if (err < 0) {
161 			dev_err(output->dev, "failed to request IRQ#%u: %d\n",
162 				output->hpd_irq, err);
163 			gpio_free(output->hpd_gpio);
164 			return err;
165 		}
166 
167 		output->connector.polled = DRM_CONNECTOR_POLL_HPD;
168 
169 		/*
170 		 * Disable the interrupt until the connector has been
171 		 * initialized to avoid a race in the hotplug interrupt
172 		 * handler.
173 		 */
174 		disable_irq(output->hpd_irq);
175 	}
176 
177 	return 0;
178 }
179 
180 void tegra_output_remove(struct tegra_output *output)
181 {
182 	if (gpio_is_valid(output->hpd_gpio)) {
183 		free_irq(output->hpd_irq, output);
184 		gpio_free(output->hpd_gpio);
185 	}
186 
187 	if (output->ddc)
188 		put_device(&output->ddc->dev);
189 }
190 
191 int tegra_output_init(struct drm_device *drm, struct tegra_output *output)
192 {
193 	int err;
194 
195 	if (output->panel) {
196 		err = drm_panel_attach(output->panel, &output->connector);
197 		if (err < 0)
198 			return err;
199 	}
200 
201 	/*
202 	 * The connector is now registered and ready to receive hotplug events
203 	 * so the hotplug interrupt can be enabled.
204 	 */
205 	if (gpio_is_valid(output->hpd_gpio))
206 		enable_irq(output->hpd_irq);
207 
208 	return 0;
209 }
210 
211 void tegra_output_exit(struct tegra_output *output)
212 {
213 	/*
214 	 * The connector is going away, so the interrupt must be disabled to
215 	 * prevent the hotplug interrupt handler from potentially crashing.
216 	 */
217 	if (gpio_is_valid(output->hpd_gpio))
218 		disable_irq(output->hpd_irq);
219 
220 	if (output->panel)
221 		drm_panel_detach(output->panel);
222 }
223