xref: /openbmc/linux/drivers/gpu/drm/sun4i/sun4i_rgb.c (revision 5d331b7f)
1 /*
2  * Copyright (C) 2015 Free Electrons
3  * Copyright (C) 2015 NextThing Co
4  *
5  * Maxime Ripard <maxime.ripard@free-electrons.com>
6  *
7  * This program is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU General Public License as
9  * published by the Free Software Foundation; either version 2 of
10  * the License, or (at your option) any later version.
11  */
12 
13 #include <linux/clk.h>
14 
15 #include <drm/drmP.h>
16 #include <drm/drm_atomic_helper.h>
17 #include <drm/drm_crtc_helper.h>
18 #include <drm/drm_of.h>
19 #include <drm/drm_panel.h>
20 
21 #include "sun4i_crtc.h"
22 #include "sun4i_tcon.h"
23 #include "sun4i_rgb.h"
24 
25 struct sun4i_rgb {
26 	struct drm_connector	connector;
27 	struct drm_encoder	encoder;
28 
29 	struct sun4i_tcon	*tcon;
30 };
31 
32 static inline struct sun4i_rgb *
33 drm_connector_to_sun4i_rgb(struct drm_connector *connector)
34 {
35 	return container_of(connector, struct sun4i_rgb,
36 			    connector);
37 }
38 
39 static inline struct sun4i_rgb *
40 drm_encoder_to_sun4i_rgb(struct drm_encoder *encoder)
41 {
42 	return container_of(encoder, struct sun4i_rgb,
43 			    encoder);
44 }
45 
46 static int sun4i_rgb_get_modes(struct drm_connector *connector)
47 {
48 	struct sun4i_rgb *rgb =
49 		drm_connector_to_sun4i_rgb(connector);
50 	struct sun4i_tcon *tcon = rgb->tcon;
51 
52 	return drm_panel_get_modes(tcon->panel);
53 }
54 
55 static enum drm_mode_status sun4i_rgb_mode_valid(struct drm_encoder *crtc,
56 						 const struct drm_display_mode *mode)
57 {
58 	struct sun4i_rgb *rgb = drm_encoder_to_sun4i_rgb(crtc);
59 	struct sun4i_tcon *tcon = rgb->tcon;
60 	u32 hsync = mode->hsync_end - mode->hsync_start;
61 	u32 vsync = mode->vsync_end - mode->vsync_start;
62 	unsigned long rate = mode->clock * 1000;
63 	long rounded_rate;
64 
65 	DRM_DEBUG_DRIVER("Validating modes...\n");
66 
67 	if (hsync < 1)
68 		return MODE_HSYNC_NARROW;
69 
70 	if (hsync > 0x3ff)
71 		return MODE_HSYNC_WIDE;
72 
73 	if ((mode->hdisplay < 1) || (mode->htotal < 1))
74 		return MODE_H_ILLEGAL;
75 
76 	if ((mode->hdisplay > 0x7ff) || (mode->htotal > 0xfff))
77 		return MODE_BAD_HVALUE;
78 
79 	DRM_DEBUG_DRIVER("Horizontal parameters OK\n");
80 
81 	if (vsync < 1)
82 		return MODE_VSYNC_NARROW;
83 
84 	if (vsync > 0x3ff)
85 		return MODE_VSYNC_WIDE;
86 
87 	if ((mode->vdisplay < 1) || (mode->vtotal < 1))
88 		return MODE_V_ILLEGAL;
89 
90 	if ((mode->vdisplay > 0x7ff) || (mode->vtotal > 0xfff))
91 		return MODE_BAD_VVALUE;
92 
93 	DRM_DEBUG_DRIVER("Vertical parameters OK\n");
94 
95 	tcon->dclk_min_div = 6;
96 	tcon->dclk_max_div = 127;
97 	rounded_rate = clk_round_rate(tcon->dclk, rate);
98 	if (rounded_rate < rate)
99 		return MODE_CLOCK_LOW;
100 
101 	if (rounded_rate > rate)
102 		return MODE_CLOCK_HIGH;
103 
104 	DRM_DEBUG_DRIVER("Clock rate OK\n");
105 
106 	return MODE_OK;
107 }
108 
109 static struct drm_connector_helper_funcs sun4i_rgb_con_helper_funcs = {
110 	.get_modes	= sun4i_rgb_get_modes,
111 };
112 
113 static void
114 sun4i_rgb_connector_destroy(struct drm_connector *connector)
115 {
116 	struct sun4i_rgb *rgb = drm_connector_to_sun4i_rgb(connector);
117 	struct sun4i_tcon *tcon = rgb->tcon;
118 
119 	drm_panel_detach(tcon->panel);
120 	drm_connector_cleanup(connector);
121 }
122 
123 static const struct drm_connector_funcs sun4i_rgb_con_funcs = {
124 	.fill_modes		= drm_helper_probe_single_connector_modes,
125 	.destroy		= sun4i_rgb_connector_destroy,
126 	.reset			= drm_atomic_helper_connector_reset,
127 	.atomic_duplicate_state	= drm_atomic_helper_connector_duplicate_state,
128 	.atomic_destroy_state	= drm_atomic_helper_connector_destroy_state,
129 };
130 
131 static void sun4i_rgb_encoder_enable(struct drm_encoder *encoder)
132 {
133 	struct sun4i_rgb *rgb = drm_encoder_to_sun4i_rgb(encoder);
134 	struct sun4i_tcon *tcon = rgb->tcon;
135 
136 	DRM_DEBUG_DRIVER("Enabling RGB output\n");
137 
138 	if (!IS_ERR(tcon->panel)) {
139 		drm_panel_prepare(tcon->panel);
140 		drm_panel_enable(tcon->panel);
141 	}
142 }
143 
144 static void sun4i_rgb_encoder_disable(struct drm_encoder *encoder)
145 {
146 	struct sun4i_rgb *rgb = drm_encoder_to_sun4i_rgb(encoder);
147 	struct sun4i_tcon *tcon = rgb->tcon;
148 
149 	DRM_DEBUG_DRIVER("Disabling RGB output\n");
150 
151 	if (!IS_ERR(tcon->panel)) {
152 		drm_panel_disable(tcon->panel);
153 		drm_panel_unprepare(tcon->panel);
154 	}
155 }
156 
157 static struct drm_encoder_helper_funcs sun4i_rgb_enc_helper_funcs = {
158 	.disable	= sun4i_rgb_encoder_disable,
159 	.enable		= sun4i_rgb_encoder_enable,
160 	.mode_valid	= sun4i_rgb_mode_valid,
161 };
162 
163 static void sun4i_rgb_enc_destroy(struct drm_encoder *encoder)
164 {
165 	drm_encoder_cleanup(encoder);
166 }
167 
168 static struct drm_encoder_funcs sun4i_rgb_enc_funcs = {
169 	.destroy	= sun4i_rgb_enc_destroy,
170 };
171 
172 int sun4i_rgb_init(struct drm_device *drm, struct sun4i_tcon *tcon)
173 {
174 	struct drm_encoder *encoder;
175 	struct drm_bridge *bridge;
176 	struct sun4i_rgb *rgb;
177 	int ret;
178 
179 	rgb = devm_kzalloc(drm->dev, sizeof(*rgb), GFP_KERNEL);
180 	if (!rgb)
181 		return -ENOMEM;
182 	rgb->tcon = tcon;
183 	encoder = &rgb->encoder;
184 
185 	ret = drm_of_find_panel_or_bridge(tcon->dev->of_node, 1, 0,
186 					  &tcon->panel, &bridge);
187 	if (ret) {
188 		dev_info(drm->dev, "No panel or bridge found... RGB output disabled\n");
189 		return 0;
190 	}
191 
192 	drm_encoder_helper_add(&rgb->encoder,
193 			       &sun4i_rgb_enc_helper_funcs);
194 	ret = drm_encoder_init(drm,
195 			       &rgb->encoder,
196 			       &sun4i_rgb_enc_funcs,
197 			       DRM_MODE_ENCODER_NONE,
198 			       NULL);
199 	if (ret) {
200 		dev_err(drm->dev, "Couldn't initialise the rgb encoder\n");
201 		goto err_out;
202 	}
203 
204 	/* The RGB encoder can only work with the TCON channel 0 */
205 	rgb->encoder.possible_crtcs = drm_crtc_mask(&tcon->crtc->crtc);
206 
207 	if (tcon->panel) {
208 		drm_connector_helper_add(&rgb->connector,
209 					 &sun4i_rgb_con_helper_funcs);
210 		ret = drm_connector_init(drm, &rgb->connector,
211 					 &sun4i_rgb_con_funcs,
212 					 DRM_MODE_CONNECTOR_Unknown);
213 		if (ret) {
214 			dev_err(drm->dev, "Couldn't initialise the rgb connector\n");
215 			goto err_cleanup_connector;
216 		}
217 
218 		drm_connector_attach_encoder(&rgb->connector,
219 						  &rgb->encoder);
220 
221 		ret = drm_panel_attach(tcon->panel, &rgb->connector);
222 		if (ret) {
223 			dev_err(drm->dev, "Couldn't attach our panel\n");
224 			goto err_cleanup_connector;
225 		}
226 	}
227 
228 	if (bridge) {
229 		ret = drm_bridge_attach(encoder, bridge, NULL);
230 		if (ret) {
231 			dev_err(drm->dev, "Couldn't attach our bridge\n");
232 			goto err_cleanup_connector;
233 		}
234 	}
235 
236 	return 0;
237 
238 err_cleanup_connector:
239 	drm_encoder_cleanup(&rgb->encoder);
240 err_out:
241 	return ret;
242 }
243 EXPORT_SYMBOL(sun4i_rgb_init);
244