xref: /linux/drivers/gpu/drm/tegra/rgb.c (revision c4ee0af3fa0dc65f690fc908f02b8355f9576ea0)
1 /*
2  * Copyright (C) 2012 Avionic Design GmbH
3  * Copyright (C) 2012 NVIDIA CORPORATION.  All rights reserved.
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License version 2 as
7  * published by the Free Software Foundation.
8  */
9 
10 #include <linux/clk.h>
11 
12 #include "drm.h"
13 #include "dc.h"
14 
15 struct tegra_rgb {
16 	struct tegra_output output;
17 	struct tegra_dc *dc;
18 
19 	struct clk *clk_parent;
20 	struct clk *clk;
21 };
22 
23 static inline struct tegra_rgb *to_rgb(struct tegra_output *output)
24 {
25 	return container_of(output, struct tegra_rgb, output);
26 }
27 
28 struct reg_entry {
29 	unsigned long offset;
30 	unsigned long value;
31 };
32 
33 static const struct reg_entry rgb_enable[] = {
34 	{ DC_COM_PIN_OUTPUT_ENABLE(0),   0x00000000 },
35 	{ DC_COM_PIN_OUTPUT_ENABLE(1),   0x00000000 },
36 	{ DC_COM_PIN_OUTPUT_ENABLE(2),   0x00000000 },
37 	{ DC_COM_PIN_OUTPUT_ENABLE(3),   0x00000000 },
38 	{ DC_COM_PIN_OUTPUT_POLARITY(0), 0x00000000 },
39 	{ DC_COM_PIN_OUTPUT_POLARITY(1), 0x01000000 },
40 	{ DC_COM_PIN_OUTPUT_POLARITY(2), 0x00000000 },
41 	{ DC_COM_PIN_OUTPUT_POLARITY(3), 0x00000000 },
42 	{ DC_COM_PIN_OUTPUT_DATA(0),     0x00000000 },
43 	{ DC_COM_PIN_OUTPUT_DATA(1),     0x00000000 },
44 	{ DC_COM_PIN_OUTPUT_DATA(2),     0x00000000 },
45 	{ DC_COM_PIN_OUTPUT_DATA(3),     0x00000000 },
46 	{ DC_COM_PIN_OUTPUT_SELECT(0),   0x00000000 },
47 	{ DC_COM_PIN_OUTPUT_SELECT(1),   0x00000000 },
48 	{ DC_COM_PIN_OUTPUT_SELECT(2),   0x00000000 },
49 	{ DC_COM_PIN_OUTPUT_SELECT(3),   0x00000000 },
50 	{ DC_COM_PIN_OUTPUT_SELECT(4),   0x00210222 },
51 	{ DC_COM_PIN_OUTPUT_SELECT(5),   0x00002200 },
52 	{ DC_COM_PIN_OUTPUT_SELECT(6),   0x00020000 },
53 };
54 
55 static const struct reg_entry rgb_disable[] = {
56 	{ DC_COM_PIN_OUTPUT_SELECT(6),   0x00000000 },
57 	{ DC_COM_PIN_OUTPUT_SELECT(5),   0x00000000 },
58 	{ DC_COM_PIN_OUTPUT_SELECT(4),   0x00000000 },
59 	{ DC_COM_PIN_OUTPUT_SELECT(3),   0x00000000 },
60 	{ DC_COM_PIN_OUTPUT_SELECT(2),   0x00000000 },
61 	{ DC_COM_PIN_OUTPUT_SELECT(1),   0x00000000 },
62 	{ DC_COM_PIN_OUTPUT_SELECT(0),   0x00000000 },
63 	{ DC_COM_PIN_OUTPUT_DATA(3),     0xaaaaaaaa },
64 	{ DC_COM_PIN_OUTPUT_DATA(2),     0xaaaaaaaa },
65 	{ DC_COM_PIN_OUTPUT_DATA(1),     0xaaaaaaaa },
66 	{ DC_COM_PIN_OUTPUT_DATA(0),     0xaaaaaaaa },
67 	{ DC_COM_PIN_OUTPUT_POLARITY(3), 0x00000000 },
68 	{ DC_COM_PIN_OUTPUT_POLARITY(2), 0x00000000 },
69 	{ DC_COM_PIN_OUTPUT_POLARITY(1), 0x00000000 },
70 	{ DC_COM_PIN_OUTPUT_POLARITY(0), 0x00000000 },
71 	{ DC_COM_PIN_OUTPUT_ENABLE(3),   0x55555555 },
72 	{ DC_COM_PIN_OUTPUT_ENABLE(2),   0x55555555 },
73 	{ DC_COM_PIN_OUTPUT_ENABLE(1),   0x55150005 },
74 	{ DC_COM_PIN_OUTPUT_ENABLE(0),   0x55555555 },
75 };
76 
77 static void tegra_dc_write_regs(struct tegra_dc *dc,
78 				const struct reg_entry *table,
79 				unsigned int num)
80 {
81 	unsigned int i;
82 
83 	for (i = 0; i < num; i++)
84 		tegra_dc_writel(dc, table[i].value, table[i].offset);
85 }
86 
87 static int tegra_output_rgb_enable(struct tegra_output *output)
88 {
89 	struct tegra_rgb *rgb = to_rgb(output);
90 
91 	tegra_dc_write_regs(rgb->dc, rgb_enable, ARRAY_SIZE(rgb_enable));
92 
93 	return 0;
94 }
95 
96 static int tegra_output_rgb_disable(struct tegra_output *output)
97 {
98 	struct tegra_rgb *rgb = to_rgb(output);
99 
100 	tegra_dc_write_regs(rgb->dc, rgb_disable, ARRAY_SIZE(rgb_disable));
101 
102 	return 0;
103 }
104 
105 static int tegra_output_rgb_setup_clock(struct tegra_output *output,
106 					struct clk *clk, unsigned long pclk)
107 {
108 	struct tegra_rgb *rgb = to_rgb(output);
109 
110 	return clk_set_parent(clk, rgb->clk_parent);
111 }
112 
113 static int tegra_output_rgb_check_mode(struct tegra_output *output,
114 				       struct drm_display_mode *mode,
115 				       enum drm_mode_status *status)
116 {
117 	/*
118 	 * FIXME: For now, always assume that the mode is okay. There are
119 	 * unresolved issues with clk_round_rate(), which doesn't always
120 	 * reliably report whether a frequency can be set or not.
121 	 */
122 
123 	*status = MODE_OK;
124 
125 	return 0;
126 }
127 
128 static const struct tegra_output_ops rgb_ops = {
129 	.enable = tegra_output_rgb_enable,
130 	.disable = tegra_output_rgb_disable,
131 	.setup_clock = tegra_output_rgb_setup_clock,
132 	.check_mode = tegra_output_rgb_check_mode,
133 };
134 
135 int tegra_dc_rgb_probe(struct tegra_dc *dc)
136 {
137 	struct device_node *np;
138 	struct tegra_rgb *rgb;
139 	int err;
140 
141 	np = of_get_child_by_name(dc->dev->of_node, "rgb");
142 	if (!np || !of_device_is_available(np))
143 		return -ENODEV;
144 
145 	rgb = devm_kzalloc(dc->dev, sizeof(*rgb), GFP_KERNEL);
146 	if (!rgb)
147 		return -ENOMEM;
148 
149 	rgb->output.dev = dc->dev;
150 	rgb->output.of_node = np;
151 	rgb->dc = dc;
152 
153 	err = tegra_output_probe(&rgb->output);
154 	if (err < 0)
155 		return err;
156 
157 	rgb->clk = devm_clk_get(dc->dev, NULL);
158 	if (IS_ERR(rgb->clk)) {
159 		dev_err(dc->dev, "failed to get clock\n");
160 		return PTR_ERR(rgb->clk);
161 	}
162 
163 	rgb->clk_parent = devm_clk_get(dc->dev, "parent");
164 	if (IS_ERR(rgb->clk_parent)) {
165 		dev_err(dc->dev, "failed to get parent clock\n");
166 		return PTR_ERR(rgb->clk_parent);
167 	}
168 
169 	err = clk_set_parent(rgb->clk, rgb->clk_parent);
170 	if (err < 0) {
171 		dev_err(dc->dev, "failed to set parent clock: %d\n", err);
172 		return err;
173 	}
174 
175 	dc->rgb = &rgb->output;
176 
177 	return 0;
178 }
179 
180 int tegra_dc_rgb_remove(struct tegra_dc *dc)
181 {
182 	int err;
183 
184 	if (!dc->rgb)
185 		return 0;
186 
187 	err = tegra_output_remove(dc->rgb);
188 	if (err < 0)
189 		return err;
190 
191 	return 0;
192 }
193 
194 int tegra_dc_rgb_init(struct drm_device *drm, struct tegra_dc *dc)
195 {
196 	struct tegra_rgb *rgb = to_rgb(dc->rgb);
197 	int err;
198 
199 	if (!dc->rgb)
200 		return -ENODEV;
201 
202 	rgb->output.type = TEGRA_OUTPUT_RGB;
203 	rgb->output.ops = &rgb_ops;
204 
205 	err = tegra_output_init(dc->base.dev, &rgb->output);
206 	if (err < 0) {
207 		dev_err(dc->dev, "output setup failed: %d\n", err);
208 		return err;
209 	}
210 
211 	/*
212 	 * By default, outputs can be associated with each display controller.
213 	 * RGB outputs are an exception, so we make sure they can be attached
214 	 * to only their parent display controller.
215 	 */
216 	rgb->output.encoder.possible_crtcs = 1 << dc->pipe;
217 
218 	return 0;
219 }
220 
221 int tegra_dc_rgb_exit(struct tegra_dc *dc)
222 {
223 	if (dc->rgb) {
224 		int err;
225 
226 		err = tegra_output_disable(dc->rgb);
227 		if (err < 0) {
228 			dev_err(dc->dev, "output failed to disable: %d\n", err);
229 			return err;
230 		}
231 
232 		err = tegra_output_exit(dc->rgb);
233 		if (err < 0) {
234 			dev_err(dc->dev, "output cleanup failed: %d\n", err);
235 			return err;
236 		}
237 
238 		dc->rgb = NULL;
239 	}
240 
241 	return 0;
242 }
243