xref: /openbmc/linux/drivers/gpu/drm/sun4i/sun4i_lvds.c (revision 5d331b7f)
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_crtc_helper.h>
12 #include <drm/drm_of.h>
13 #include <drm/drm_panel.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 sun4i_tcon	*tcon;
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 	struct sun4i_tcon *tcon = lvds->tcon;
45 
46 	return drm_panel_get_modes(tcon->panel);
47 }
48 
49 static struct drm_connector_helper_funcs sun4i_lvds_con_helper_funcs = {
50 	.get_modes	= sun4i_lvds_get_modes,
51 };
52 
53 static void
54 sun4i_lvds_connector_destroy(struct drm_connector *connector)
55 {
56 	struct sun4i_lvds *lvds = drm_connector_to_sun4i_lvds(connector);
57 	struct sun4i_tcon *tcon = lvds->tcon;
58 
59 	drm_panel_detach(tcon->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 	struct sun4i_tcon *tcon = lvds->tcon;
75 
76 	DRM_DEBUG_DRIVER("Enabling LVDS output\n");
77 
78 	if (!IS_ERR(tcon->panel)) {
79 		drm_panel_prepare(tcon->panel);
80 		drm_panel_enable(tcon->panel);
81 	}
82 }
83 
84 static void sun4i_lvds_encoder_disable(struct drm_encoder *encoder)
85 {
86 	struct sun4i_lvds *lvds = drm_encoder_to_sun4i_lvds(encoder);
87 	struct sun4i_tcon *tcon = lvds->tcon;
88 
89 	DRM_DEBUG_DRIVER("Disabling LVDS output\n");
90 
91 	if (!IS_ERR(tcon->panel)) {
92 		drm_panel_disable(tcon->panel);
93 		drm_panel_unprepare(tcon->panel);
94 	}
95 }
96 
97 static const struct drm_encoder_helper_funcs sun4i_lvds_enc_helper_funcs = {
98 	.disable	= sun4i_lvds_encoder_disable,
99 	.enable		= sun4i_lvds_encoder_enable,
100 };
101 
102 static const struct drm_encoder_funcs sun4i_lvds_enc_funcs = {
103 	.destroy	= drm_encoder_cleanup,
104 };
105 
106 int sun4i_lvds_init(struct drm_device *drm, struct sun4i_tcon *tcon)
107 {
108 	struct drm_encoder *encoder;
109 	struct drm_bridge *bridge;
110 	struct sun4i_lvds *lvds;
111 	int ret;
112 
113 	lvds = devm_kzalloc(drm->dev, sizeof(*lvds), GFP_KERNEL);
114 	if (!lvds)
115 		return -ENOMEM;
116 	lvds->tcon = tcon;
117 	encoder = &lvds->encoder;
118 
119 	ret = drm_of_find_panel_or_bridge(tcon->dev->of_node, 1, 0,
120 					  &tcon->panel, &bridge);
121 	if (ret) {
122 		dev_info(drm->dev, "No panel or bridge found... LVDS output disabled\n");
123 		return 0;
124 	}
125 
126 	drm_encoder_helper_add(&lvds->encoder,
127 			       &sun4i_lvds_enc_helper_funcs);
128 	ret = drm_encoder_init(drm,
129 			       &lvds->encoder,
130 			       &sun4i_lvds_enc_funcs,
131 			       DRM_MODE_ENCODER_LVDS,
132 			       NULL);
133 	if (ret) {
134 		dev_err(drm->dev, "Couldn't initialise the lvds encoder\n");
135 		goto err_out;
136 	}
137 
138 	/* The LVDS encoder can only work with the TCON channel 0 */
139 	lvds->encoder.possible_crtcs = drm_crtc_mask(&tcon->crtc->crtc);
140 
141 	if (tcon->panel) {
142 		drm_connector_helper_add(&lvds->connector,
143 					 &sun4i_lvds_con_helper_funcs);
144 		ret = drm_connector_init(drm, &lvds->connector,
145 					 &sun4i_lvds_con_funcs,
146 					 DRM_MODE_CONNECTOR_LVDS);
147 		if (ret) {
148 			dev_err(drm->dev, "Couldn't initialise the lvds connector\n");
149 			goto err_cleanup_connector;
150 		}
151 
152 		drm_connector_attach_encoder(&lvds->connector,
153 						  &lvds->encoder);
154 
155 		ret = drm_panel_attach(tcon->panel, &lvds->connector);
156 		if (ret) {
157 			dev_err(drm->dev, "Couldn't attach our panel\n");
158 			goto err_cleanup_connector;
159 		}
160 	}
161 
162 	if (bridge) {
163 		ret = drm_bridge_attach(encoder, bridge, NULL);
164 		if (ret) {
165 			dev_err(drm->dev, "Couldn't attach our bridge\n");
166 			goto err_cleanup_connector;
167 		}
168 	}
169 
170 	return 0;
171 
172 err_cleanup_connector:
173 	drm_encoder_cleanup(&lvds->encoder);
174 err_out:
175 	return ret;
176 }
177 EXPORT_SYMBOL(sun4i_lvds_init);
178