xref: /openbmc/linux/drivers/gpu/drm/sun4i/sun4i_lvds.c (revision 82df5b73)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2017 Free Electrons
4  * Maxime Ripard <maxime.ripard@free-electrons.com>
5  */
6 
7 #include <linux/clk.h>
8 
9 #include <drm/drm_atomic_helper.h>
10 #include <drm/drm_bridge.h>
11 #include <drm/drm_of.h>
12 #include <drm/drm_panel.h>
13 #include <drm/drm_print.h>
14 #include <drm/drm_probe_helper.h>
15 #include <drm/drm_simple_kms_helper.h>
16 
17 #include "sun4i_crtc.h"
18 #include "sun4i_tcon.h"
19 #include "sun4i_lvds.h"
20 
21 struct sun4i_lvds {
22 	struct drm_connector	connector;
23 	struct drm_encoder	encoder;
24 
25 	struct drm_panel	*panel;
26 };
27 
28 static inline struct sun4i_lvds *
29 drm_connector_to_sun4i_lvds(struct drm_connector *connector)
30 {
31 	return container_of(connector, struct sun4i_lvds,
32 			    connector);
33 }
34 
35 static inline struct sun4i_lvds *
36 drm_encoder_to_sun4i_lvds(struct drm_encoder *encoder)
37 {
38 	return container_of(encoder, struct sun4i_lvds,
39 			    encoder);
40 }
41 
42 static int sun4i_lvds_get_modes(struct drm_connector *connector)
43 {
44 	struct sun4i_lvds *lvds =
45 		drm_connector_to_sun4i_lvds(connector);
46 
47 	return drm_panel_get_modes(lvds->panel, connector);
48 }
49 
50 static struct drm_connector_helper_funcs sun4i_lvds_con_helper_funcs = {
51 	.get_modes	= sun4i_lvds_get_modes,
52 };
53 
54 static void
55 sun4i_lvds_connector_destroy(struct drm_connector *connector)
56 {
57 	struct sun4i_lvds *lvds = drm_connector_to_sun4i_lvds(connector);
58 
59 	drm_panel_detach(lvds->panel);
60 	drm_connector_cleanup(connector);
61 }
62 
63 static const struct drm_connector_funcs sun4i_lvds_con_funcs = {
64 	.fill_modes		= drm_helper_probe_single_connector_modes,
65 	.destroy		= sun4i_lvds_connector_destroy,
66 	.reset			= drm_atomic_helper_connector_reset,
67 	.atomic_duplicate_state	= drm_atomic_helper_connector_duplicate_state,
68 	.atomic_destroy_state	= drm_atomic_helper_connector_destroy_state,
69 };
70 
71 static void sun4i_lvds_encoder_enable(struct drm_encoder *encoder)
72 {
73 	struct sun4i_lvds *lvds = drm_encoder_to_sun4i_lvds(encoder);
74 
75 	DRM_DEBUG_DRIVER("Enabling LVDS output\n");
76 
77 	if (lvds->panel) {
78 		drm_panel_prepare(lvds->panel);
79 		drm_panel_enable(lvds->panel);
80 	}
81 }
82 
83 static void sun4i_lvds_encoder_disable(struct drm_encoder *encoder)
84 {
85 	struct sun4i_lvds *lvds = drm_encoder_to_sun4i_lvds(encoder);
86 
87 	DRM_DEBUG_DRIVER("Disabling LVDS output\n");
88 
89 	if (lvds->panel) {
90 		drm_panel_disable(lvds->panel);
91 		drm_panel_unprepare(lvds->panel);
92 	}
93 }
94 
95 static const struct drm_encoder_helper_funcs sun4i_lvds_enc_helper_funcs = {
96 	.disable	= sun4i_lvds_encoder_disable,
97 	.enable		= sun4i_lvds_encoder_enable,
98 };
99 
100 int sun4i_lvds_init(struct drm_device *drm, struct sun4i_tcon *tcon)
101 {
102 	struct drm_encoder *encoder;
103 	struct drm_bridge *bridge;
104 	struct sun4i_lvds *lvds;
105 	int ret;
106 
107 	lvds = devm_kzalloc(drm->dev, sizeof(*lvds), GFP_KERNEL);
108 	if (!lvds)
109 		return -ENOMEM;
110 	encoder = &lvds->encoder;
111 
112 	ret = drm_of_find_panel_or_bridge(tcon->dev->of_node, 1, 0,
113 					  &lvds->panel, &bridge);
114 	if (ret) {
115 		dev_info(drm->dev, "No panel or bridge found... LVDS output disabled\n");
116 		return 0;
117 	}
118 
119 	drm_encoder_helper_add(&lvds->encoder,
120 			       &sun4i_lvds_enc_helper_funcs);
121 	ret = drm_simple_encoder_init(drm, &lvds->encoder,
122 				      DRM_MODE_ENCODER_LVDS);
123 	if (ret) {
124 		dev_err(drm->dev, "Couldn't initialise the lvds encoder\n");
125 		goto err_out;
126 	}
127 
128 	/* The LVDS encoder can only work with the TCON channel 0 */
129 	lvds->encoder.possible_crtcs = drm_crtc_mask(&tcon->crtc->crtc);
130 
131 	if (lvds->panel) {
132 		drm_connector_helper_add(&lvds->connector,
133 					 &sun4i_lvds_con_helper_funcs);
134 		ret = drm_connector_init(drm, &lvds->connector,
135 					 &sun4i_lvds_con_funcs,
136 					 DRM_MODE_CONNECTOR_LVDS);
137 		if (ret) {
138 			dev_err(drm->dev, "Couldn't initialise the lvds connector\n");
139 			goto err_cleanup_connector;
140 		}
141 
142 		drm_connector_attach_encoder(&lvds->connector,
143 						  &lvds->encoder);
144 
145 		ret = drm_panel_attach(lvds->panel, &lvds->connector);
146 		if (ret) {
147 			dev_err(drm->dev, "Couldn't attach our panel\n");
148 			goto err_cleanup_connector;
149 		}
150 	}
151 
152 	if (bridge) {
153 		ret = drm_bridge_attach(encoder, bridge, NULL, 0);
154 		if (ret) {
155 			dev_err(drm->dev, "Couldn't attach our bridge\n");
156 			goto err_cleanup_connector;
157 		}
158 	}
159 
160 	return 0;
161 
162 err_cleanup_connector:
163 	drm_encoder_cleanup(&lvds->encoder);
164 err_out:
165 	return ret;
166 }
167 EXPORT_SYMBOL(sun4i_lvds_init);
168