xref: /openbmc/linux/drivers/gpu/drm/sun4i/sun4i_lvds.c (revision d2574c33)
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/drmP.h>
10 #include <drm/drm_atomic_helper.h>
11 #include <drm/drm_of.h>
12 #include <drm/drm_panel.h>
13 #include <drm/drm_probe_helper.h>
14 
15 #include "sun4i_crtc.h"
16 #include "sun4i_tcon.h"
17 #include "sun4i_lvds.h"
18 
19 struct sun4i_lvds {
20 	struct drm_connector	connector;
21 	struct drm_encoder	encoder;
22 
23 	struct drm_panel	*panel;
24 };
25 
26 static inline struct sun4i_lvds *
27 drm_connector_to_sun4i_lvds(struct drm_connector *connector)
28 {
29 	return container_of(connector, struct sun4i_lvds,
30 			    connector);
31 }
32 
33 static inline struct sun4i_lvds *
34 drm_encoder_to_sun4i_lvds(struct drm_encoder *encoder)
35 {
36 	return container_of(encoder, struct sun4i_lvds,
37 			    encoder);
38 }
39 
40 static int sun4i_lvds_get_modes(struct drm_connector *connector)
41 {
42 	struct sun4i_lvds *lvds =
43 		drm_connector_to_sun4i_lvds(connector);
44 
45 	return drm_panel_get_modes(lvds->panel);
46 }
47 
48 static struct drm_connector_helper_funcs sun4i_lvds_con_helper_funcs = {
49 	.get_modes	= sun4i_lvds_get_modes,
50 };
51 
52 static void
53 sun4i_lvds_connector_destroy(struct drm_connector *connector)
54 {
55 	struct sun4i_lvds *lvds = drm_connector_to_sun4i_lvds(connector);
56 
57 	drm_panel_detach(lvds->panel);
58 	drm_connector_cleanup(connector);
59 }
60 
61 static const struct drm_connector_funcs sun4i_lvds_con_funcs = {
62 	.fill_modes		= drm_helper_probe_single_connector_modes,
63 	.destroy		= sun4i_lvds_connector_destroy,
64 	.reset			= drm_atomic_helper_connector_reset,
65 	.atomic_duplicate_state	= drm_atomic_helper_connector_duplicate_state,
66 	.atomic_destroy_state	= drm_atomic_helper_connector_destroy_state,
67 };
68 
69 static void sun4i_lvds_encoder_enable(struct drm_encoder *encoder)
70 {
71 	struct sun4i_lvds *lvds = drm_encoder_to_sun4i_lvds(encoder);
72 
73 	DRM_DEBUG_DRIVER("Enabling LVDS output\n");
74 
75 	if (lvds->panel) {
76 		drm_panel_prepare(lvds->panel);
77 		drm_panel_enable(lvds->panel);
78 	}
79 }
80 
81 static void sun4i_lvds_encoder_disable(struct drm_encoder *encoder)
82 {
83 	struct sun4i_lvds *lvds = drm_encoder_to_sun4i_lvds(encoder);
84 
85 	DRM_DEBUG_DRIVER("Disabling LVDS output\n");
86 
87 	if (lvds->panel) {
88 		drm_panel_disable(lvds->panel);
89 		drm_panel_unprepare(lvds->panel);
90 	}
91 }
92 
93 static const struct drm_encoder_helper_funcs sun4i_lvds_enc_helper_funcs = {
94 	.disable	= sun4i_lvds_encoder_disable,
95 	.enable		= sun4i_lvds_encoder_enable,
96 };
97 
98 static const struct drm_encoder_funcs sun4i_lvds_enc_funcs = {
99 	.destroy	= drm_encoder_cleanup,
100 };
101 
102 int sun4i_lvds_init(struct drm_device *drm, struct sun4i_tcon *tcon)
103 {
104 	struct drm_encoder *encoder;
105 	struct drm_bridge *bridge;
106 	struct sun4i_lvds *lvds;
107 	int ret;
108 
109 	lvds = devm_kzalloc(drm->dev, sizeof(*lvds), GFP_KERNEL);
110 	if (!lvds)
111 		return -ENOMEM;
112 	encoder = &lvds->encoder;
113 
114 	ret = drm_of_find_panel_or_bridge(tcon->dev->of_node, 1, 0,
115 					  &lvds->panel, &bridge);
116 	if (ret) {
117 		dev_info(drm->dev, "No panel or bridge found... LVDS output disabled\n");
118 		return 0;
119 	}
120 
121 	drm_encoder_helper_add(&lvds->encoder,
122 			       &sun4i_lvds_enc_helper_funcs);
123 	ret = drm_encoder_init(drm,
124 			       &lvds->encoder,
125 			       &sun4i_lvds_enc_funcs,
126 			       DRM_MODE_ENCODER_LVDS,
127 			       NULL);
128 	if (ret) {
129 		dev_err(drm->dev, "Couldn't initialise the lvds encoder\n");
130 		goto err_out;
131 	}
132 
133 	/* The LVDS encoder can only work with the TCON channel 0 */
134 	lvds->encoder.possible_crtcs = drm_crtc_mask(&tcon->crtc->crtc);
135 
136 	if (lvds->panel) {
137 		drm_connector_helper_add(&lvds->connector,
138 					 &sun4i_lvds_con_helper_funcs);
139 		ret = drm_connector_init(drm, &lvds->connector,
140 					 &sun4i_lvds_con_funcs,
141 					 DRM_MODE_CONNECTOR_LVDS);
142 		if (ret) {
143 			dev_err(drm->dev, "Couldn't initialise the lvds connector\n");
144 			goto err_cleanup_connector;
145 		}
146 
147 		drm_connector_attach_encoder(&lvds->connector,
148 						  &lvds->encoder);
149 
150 		ret = drm_panel_attach(lvds->panel, &lvds->connector);
151 		if (ret) {
152 			dev_err(drm->dev, "Couldn't attach our panel\n");
153 			goto err_cleanup_connector;
154 		}
155 	}
156 
157 	if (bridge) {
158 		ret = drm_bridge_attach(encoder, bridge, NULL);
159 		if (ret) {
160 			dev_err(drm->dev, "Couldn't attach our bridge\n");
161 			goto err_cleanup_connector;
162 		}
163 	}
164 
165 	return 0;
166 
167 err_cleanup_connector:
168 	drm_encoder_cleanup(&lvds->encoder);
169 err_out:
170 	return ret;
171 }
172 EXPORT_SYMBOL(sun4i_lvds_init);
173