xref: /openbmc/linux/drivers/gpu/drm/sun4i/sun4i_lvds.c (revision bbb774d9)
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 const 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 	drm_connector_cleanup(connector);
58 }
59 
60 static const struct drm_connector_funcs sun4i_lvds_con_funcs = {
61 	.fill_modes		= drm_helper_probe_single_connector_modes,
62 	.destroy		= sun4i_lvds_connector_destroy,
63 	.reset			= drm_atomic_helper_connector_reset,
64 	.atomic_duplicate_state	= drm_atomic_helper_connector_duplicate_state,
65 	.atomic_destroy_state	= drm_atomic_helper_connector_destroy_state,
66 };
67 
68 static void sun4i_lvds_encoder_enable(struct drm_encoder *encoder)
69 {
70 	struct sun4i_lvds *lvds = drm_encoder_to_sun4i_lvds(encoder);
71 
72 	DRM_DEBUG_DRIVER("Enabling LVDS output\n");
73 
74 	if (lvds->panel) {
75 		drm_panel_prepare(lvds->panel);
76 		drm_panel_enable(lvds->panel);
77 	}
78 }
79 
80 static void sun4i_lvds_encoder_disable(struct drm_encoder *encoder)
81 {
82 	struct sun4i_lvds *lvds = drm_encoder_to_sun4i_lvds(encoder);
83 
84 	DRM_DEBUG_DRIVER("Disabling LVDS output\n");
85 
86 	if (lvds->panel) {
87 		drm_panel_disable(lvds->panel);
88 		drm_panel_unprepare(lvds->panel);
89 	}
90 }
91 
92 static const struct drm_encoder_helper_funcs sun4i_lvds_enc_helper_funcs = {
93 	.disable	= sun4i_lvds_encoder_disable,
94 	.enable		= sun4i_lvds_encoder_enable,
95 };
96 
97 int sun4i_lvds_init(struct drm_device *drm, struct sun4i_tcon *tcon)
98 {
99 	struct drm_encoder *encoder;
100 	struct drm_bridge *bridge;
101 	struct sun4i_lvds *lvds;
102 	int ret;
103 
104 	lvds = devm_kzalloc(drm->dev, sizeof(*lvds), GFP_KERNEL);
105 	if (!lvds)
106 		return -ENOMEM;
107 	encoder = &lvds->encoder;
108 
109 	ret = drm_of_find_panel_or_bridge(tcon->dev->of_node, 1, 0,
110 					  &lvds->panel, &bridge);
111 	if (ret) {
112 		dev_info(drm->dev, "No panel or bridge found... LVDS output disabled\n");
113 		return 0;
114 	}
115 
116 	drm_encoder_helper_add(&lvds->encoder,
117 			       &sun4i_lvds_enc_helper_funcs);
118 	ret = drm_simple_encoder_init(drm, &lvds->encoder,
119 				      DRM_MODE_ENCODER_LVDS);
120 	if (ret) {
121 		dev_err(drm->dev, "Couldn't initialise the lvds encoder\n");
122 		goto err_out;
123 	}
124 
125 	/* The LVDS encoder can only work with the TCON channel 0 */
126 	lvds->encoder.possible_crtcs = drm_crtc_mask(&tcon->crtc->crtc);
127 
128 	if (lvds->panel) {
129 		drm_connector_helper_add(&lvds->connector,
130 					 &sun4i_lvds_con_helper_funcs);
131 		ret = drm_connector_init(drm, &lvds->connector,
132 					 &sun4i_lvds_con_funcs,
133 					 DRM_MODE_CONNECTOR_LVDS);
134 		if (ret) {
135 			dev_err(drm->dev, "Couldn't initialise the lvds connector\n");
136 			goto err_cleanup_connector;
137 		}
138 
139 		drm_connector_attach_encoder(&lvds->connector,
140 						  &lvds->encoder);
141 	}
142 
143 	if (bridge) {
144 		ret = drm_bridge_attach(encoder, bridge, NULL, 0);
145 		if (ret)
146 			goto err_cleanup_connector;
147 	}
148 
149 	return 0;
150 
151 err_cleanup_connector:
152 	drm_encoder_cleanup(&lvds->encoder);
153 err_out:
154 	return ret;
155 }
156 EXPORT_SYMBOL(sun4i_lvds_init);
157