1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (c) 2018 Jernej Skrabec <jernej.skrabec@siol.net>
4  */
5 
6 #include <linux/component.h>
7 #include <linux/module.h>
8 #include <linux/of_device.h>
9 #include <linux/platform_device.h>
10 
11 #include <drm/drm_of.h>
12 #include <drm/drmP.h>
13 #include <drm/drm_crtc_helper.h>
14 
15 #include "sun8i_dw_hdmi.h"
16 #include "sun8i_tcon_top.h"
17 
18 static void sun8i_dw_hdmi_encoder_mode_set(struct drm_encoder *encoder,
19 					   struct drm_display_mode *mode,
20 					   struct drm_display_mode *adj_mode)
21 {
22 	struct sun8i_dw_hdmi *hdmi = encoder_to_sun8i_dw_hdmi(encoder);
23 
24 	if (hdmi->quirks->set_rate)
25 		clk_set_rate(hdmi->clk_tmds, mode->crtc_clock * 1000);
26 }
27 
28 static const struct drm_encoder_helper_funcs
29 sun8i_dw_hdmi_encoder_helper_funcs = {
30 	.mode_set = sun8i_dw_hdmi_encoder_mode_set,
31 };
32 
33 static const struct drm_encoder_funcs sun8i_dw_hdmi_encoder_funcs = {
34 	.destroy = drm_encoder_cleanup,
35 };
36 
37 static enum drm_mode_status
38 sun8i_dw_hdmi_mode_valid_a83t(struct drm_connector *connector,
39 			      const struct drm_display_mode *mode)
40 {
41 	if (mode->clock > 297000)
42 		return MODE_CLOCK_HIGH;
43 
44 	return MODE_OK;
45 }
46 
47 static enum drm_mode_status
48 sun8i_dw_hdmi_mode_valid_h6(struct drm_connector *connector,
49 			    const struct drm_display_mode *mode)
50 {
51 	/*
52 	 * Controller support maximum of 594 MHz, which correlates to
53 	 * 4K@60Hz 4:4:4 or RGB. However, for frequencies greater than
54 	 * 340 MHz scrambling has to be enabled. Because scrambling is
55 	 * not yet implemented, just limit to 340 MHz for now.
56 	 */
57 	if (mode->clock > 340000)
58 		return MODE_CLOCK_HIGH;
59 
60 	return MODE_OK;
61 }
62 
63 static bool sun8i_dw_hdmi_node_is_tcon_top(struct device_node *node)
64 {
65 	return IS_ENABLED(CONFIG_DRM_SUN8I_TCON_TOP) &&
66 		!!of_match_node(sun8i_tcon_top_of_table, node);
67 }
68 
69 static u32 sun8i_dw_hdmi_find_possible_crtcs(struct drm_device *drm,
70 					     struct device_node *node)
71 {
72 	struct device_node *port, *ep, *remote, *remote_port;
73 	u32 crtcs = 0;
74 
75 	remote = of_graph_get_remote_node(node, 0, -1);
76 	if (!remote)
77 		return 0;
78 
79 	if (sun8i_dw_hdmi_node_is_tcon_top(remote)) {
80 		port = of_graph_get_port_by_id(remote, 4);
81 		if (!port)
82 			goto crtcs_exit;
83 
84 		for_each_child_of_node(port, ep) {
85 			remote_port = of_graph_get_remote_port(ep);
86 			if (remote_port) {
87 				crtcs |= drm_of_crtc_port_mask(drm, remote_port);
88 				of_node_put(remote_port);
89 			}
90 		}
91 	} else {
92 		crtcs = drm_of_find_possible_crtcs(drm, node);
93 	}
94 
95 crtcs_exit:
96 	of_node_put(remote);
97 
98 	return crtcs;
99 }
100 
101 static int sun8i_dw_hdmi_bind(struct device *dev, struct device *master,
102 			      void *data)
103 {
104 	struct platform_device *pdev = to_platform_device(dev);
105 	struct dw_hdmi_plat_data *plat_data;
106 	struct drm_device *drm = data;
107 	struct device_node *phy_node;
108 	struct drm_encoder *encoder;
109 	struct sun8i_dw_hdmi *hdmi;
110 	int ret;
111 
112 	if (!pdev->dev.of_node)
113 		return -ENODEV;
114 
115 	hdmi = devm_kzalloc(&pdev->dev, sizeof(*hdmi), GFP_KERNEL);
116 	if (!hdmi)
117 		return -ENOMEM;
118 
119 	plat_data = &hdmi->plat_data;
120 	hdmi->dev = &pdev->dev;
121 	encoder = &hdmi->encoder;
122 
123 	hdmi->quirks = of_device_get_match_data(dev);
124 
125 	encoder->possible_crtcs =
126 		sun8i_dw_hdmi_find_possible_crtcs(drm, dev->of_node);
127 	/*
128 	 * If we failed to find the CRTC(s) which this encoder is
129 	 * supposed to be connected to, it's because the CRTC has
130 	 * not been registered yet.  Defer probing, and hope that
131 	 * the required CRTC is added later.
132 	 */
133 	if (encoder->possible_crtcs == 0)
134 		return -EPROBE_DEFER;
135 
136 	hdmi->rst_ctrl = devm_reset_control_get(dev, "ctrl");
137 	if (IS_ERR(hdmi->rst_ctrl)) {
138 		dev_err(dev, "Could not get ctrl reset control\n");
139 		return PTR_ERR(hdmi->rst_ctrl);
140 	}
141 
142 	hdmi->clk_tmds = devm_clk_get(dev, "tmds");
143 	if (IS_ERR(hdmi->clk_tmds)) {
144 		dev_err(dev, "Couldn't get the tmds clock\n");
145 		return PTR_ERR(hdmi->clk_tmds);
146 	}
147 
148 	hdmi->regulator = devm_regulator_get(dev, "hvcc");
149 	if (IS_ERR(hdmi->regulator)) {
150 		dev_err(dev, "Couldn't get regulator\n");
151 		return PTR_ERR(hdmi->regulator);
152 	}
153 
154 	ret = regulator_enable(hdmi->regulator);
155 	if (ret) {
156 		dev_err(dev, "Failed to enable regulator\n");
157 		return ret;
158 	}
159 
160 	ret = reset_control_deassert(hdmi->rst_ctrl);
161 	if (ret) {
162 		dev_err(dev, "Could not deassert ctrl reset control\n");
163 		goto err_disable_regulator;
164 	}
165 
166 	ret = clk_prepare_enable(hdmi->clk_tmds);
167 	if (ret) {
168 		dev_err(dev, "Could not enable tmds clock\n");
169 		goto err_assert_ctrl_reset;
170 	}
171 
172 	phy_node = of_parse_phandle(dev->of_node, "phys", 0);
173 	if (!phy_node) {
174 		dev_err(dev, "Can't found PHY phandle\n");
175 		goto err_disable_clk_tmds;
176 	}
177 
178 	ret = sun8i_hdmi_phy_probe(hdmi, phy_node);
179 	of_node_put(phy_node);
180 	if (ret) {
181 		dev_err(dev, "Couldn't get the HDMI PHY\n");
182 		goto err_disable_clk_tmds;
183 	}
184 
185 	drm_encoder_helper_add(encoder, &sun8i_dw_hdmi_encoder_helper_funcs);
186 	drm_encoder_init(drm, encoder, &sun8i_dw_hdmi_encoder_funcs,
187 			 DRM_MODE_ENCODER_TMDS, NULL);
188 
189 	sun8i_hdmi_phy_init(hdmi->phy);
190 
191 	plat_data->mode_valid = hdmi->quirks->mode_valid;
192 	sun8i_hdmi_phy_set_ops(hdmi->phy, plat_data);
193 
194 	platform_set_drvdata(pdev, hdmi);
195 
196 	hdmi->hdmi = dw_hdmi_bind(pdev, encoder, plat_data);
197 
198 	/*
199 	 * If dw_hdmi_bind() fails we'll never call dw_hdmi_unbind(),
200 	 * which would have called the encoder cleanup.  Do it manually.
201 	 */
202 	if (IS_ERR(hdmi->hdmi)) {
203 		ret = PTR_ERR(hdmi->hdmi);
204 		goto cleanup_encoder;
205 	}
206 
207 	return 0;
208 
209 cleanup_encoder:
210 	drm_encoder_cleanup(encoder);
211 	sun8i_hdmi_phy_remove(hdmi);
212 err_disable_clk_tmds:
213 	clk_disable_unprepare(hdmi->clk_tmds);
214 err_assert_ctrl_reset:
215 	reset_control_assert(hdmi->rst_ctrl);
216 err_disable_regulator:
217 	regulator_disable(hdmi->regulator);
218 
219 	return ret;
220 }
221 
222 static void sun8i_dw_hdmi_unbind(struct device *dev, struct device *master,
223 				 void *data)
224 {
225 	struct sun8i_dw_hdmi *hdmi = dev_get_drvdata(dev);
226 
227 	dw_hdmi_unbind(hdmi->hdmi);
228 	sun8i_hdmi_phy_remove(hdmi);
229 	clk_disable_unprepare(hdmi->clk_tmds);
230 	reset_control_assert(hdmi->rst_ctrl);
231 	regulator_disable(hdmi->regulator);
232 }
233 
234 static const struct component_ops sun8i_dw_hdmi_ops = {
235 	.bind	= sun8i_dw_hdmi_bind,
236 	.unbind	= sun8i_dw_hdmi_unbind,
237 };
238 
239 static int sun8i_dw_hdmi_probe(struct platform_device *pdev)
240 {
241 	return component_add(&pdev->dev, &sun8i_dw_hdmi_ops);
242 }
243 
244 static int sun8i_dw_hdmi_remove(struct platform_device *pdev)
245 {
246 	component_del(&pdev->dev, &sun8i_dw_hdmi_ops);
247 
248 	return 0;
249 }
250 
251 static const struct sun8i_dw_hdmi_quirks sun8i_a83t_quirks = {
252 	.mode_valid = sun8i_dw_hdmi_mode_valid_a83t,
253 	.set_rate = true,
254 };
255 
256 static const struct sun8i_dw_hdmi_quirks sun50i_h6_quirks = {
257 	.mode_valid = sun8i_dw_hdmi_mode_valid_h6,
258 };
259 
260 static const struct of_device_id sun8i_dw_hdmi_dt_ids[] = {
261 	{
262 		.compatible = "allwinner,sun8i-a83t-dw-hdmi",
263 		.data = &sun8i_a83t_quirks,
264 	},
265 	{
266 		.compatible = "allwinner,sun50i-h6-dw-hdmi",
267 		.data = &sun50i_h6_quirks,
268 	},
269 	{ /* sentinel */ },
270 };
271 MODULE_DEVICE_TABLE(of, sun8i_dw_hdmi_dt_ids);
272 
273 static struct platform_driver sun8i_dw_hdmi_pltfm_driver = {
274 	.probe  = sun8i_dw_hdmi_probe,
275 	.remove = sun8i_dw_hdmi_remove,
276 	.driver = {
277 		.name = "sun8i-dw-hdmi",
278 		.of_match_table = sun8i_dw_hdmi_dt_ids,
279 	},
280 };
281 module_platform_driver(sun8i_dw_hdmi_pltfm_driver);
282 
283 MODULE_AUTHOR("Jernej Skrabec <jernej.skrabec@siol.net>");
284 MODULE_DESCRIPTION("Allwinner DW HDMI bridge");
285 MODULE_LICENSE("GPL");
286