xref: /openbmc/linux/drivers/gpu/drm/tegra/output.c (revision c819e2cf)
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/of_gpio.h>
11 
12 #include <drm/drm_panel.h>
13 #include "drm.h"
14 
15 static int tegra_connector_get_modes(struct drm_connector *connector)
16 {
17 	struct tegra_output *output = connector_to_output(connector);
18 	struct edid *edid = NULL;
19 	int err = 0;
20 
21 	/*
22 	 * If the panel provides one or more modes, use them exclusively and
23 	 * ignore any other means of obtaining a mode.
24 	 */
25 	if (output->panel) {
26 		err = output->panel->funcs->get_modes(output->panel);
27 		if (err > 0)
28 			return err;
29 	}
30 
31 	if (output->edid)
32 		edid = kmemdup(output->edid, sizeof(*edid), GFP_KERNEL);
33 	else if (output->ddc)
34 		edid = drm_get_edid(connector, output->ddc);
35 
36 	drm_mode_connector_update_edid_property(connector, edid);
37 
38 	if (edid) {
39 		err = drm_add_edid_modes(connector, edid);
40 		kfree(edid);
41 	}
42 
43 	return err;
44 }
45 
46 static int tegra_connector_mode_valid(struct drm_connector *connector,
47 				      struct drm_display_mode *mode)
48 {
49 	struct tegra_output *output = connector_to_output(connector);
50 	enum drm_mode_status status = MODE_OK;
51 	int err;
52 
53 	err = tegra_output_check_mode(output, mode, &status);
54 	if (err < 0)
55 		return MODE_ERROR;
56 
57 	return status;
58 }
59 
60 static struct drm_encoder *
61 tegra_connector_best_encoder(struct drm_connector *connector)
62 {
63 	struct tegra_output *output = connector_to_output(connector);
64 
65 	return &output->encoder;
66 }
67 
68 static const struct drm_connector_helper_funcs connector_helper_funcs = {
69 	.get_modes = tegra_connector_get_modes,
70 	.mode_valid = tegra_connector_mode_valid,
71 	.best_encoder = tegra_connector_best_encoder,
72 };
73 
74 static enum drm_connector_status
75 tegra_connector_detect(struct drm_connector *connector, bool force)
76 {
77 	struct tegra_output *output = connector_to_output(connector);
78 	enum drm_connector_status status = connector_status_unknown;
79 
80 	if (output->ops->detect)
81 		return output->ops->detect(output);
82 
83 	if (gpio_is_valid(output->hpd_gpio)) {
84 		if (gpio_get_value(output->hpd_gpio) == 0)
85 			status = connector_status_disconnected;
86 		else
87 			status = connector_status_connected;
88 	} else {
89 		if (!output->panel)
90 			status = connector_status_disconnected;
91 		else
92 			status = connector_status_connected;
93 
94 		if (connector->connector_type == DRM_MODE_CONNECTOR_LVDS)
95 			status = connector_status_connected;
96 	}
97 
98 	return status;
99 }
100 
101 static void drm_connector_clear(struct drm_connector *connector)
102 {
103 	memset(connector, 0, sizeof(*connector));
104 }
105 
106 static void tegra_connector_destroy(struct drm_connector *connector)
107 {
108 	drm_connector_unregister(connector);
109 	drm_connector_cleanup(connector);
110 	drm_connector_clear(connector);
111 }
112 
113 static const struct drm_connector_funcs connector_funcs = {
114 	.dpms = drm_helper_connector_dpms,
115 	.detect = tegra_connector_detect,
116 	.fill_modes = drm_helper_probe_single_connector_modes,
117 	.destroy = tegra_connector_destroy,
118 };
119 
120 static void drm_encoder_clear(struct drm_encoder *encoder)
121 {
122 	memset(encoder, 0, sizeof(*encoder));
123 }
124 
125 static void tegra_encoder_destroy(struct drm_encoder *encoder)
126 {
127 	drm_encoder_cleanup(encoder);
128 	drm_encoder_clear(encoder);
129 }
130 
131 static const struct drm_encoder_funcs encoder_funcs = {
132 	.destroy = tegra_encoder_destroy,
133 };
134 
135 static void tegra_encoder_dpms(struct drm_encoder *encoder, int mode)
136 {
137 	struct tegra_output *output = encoder_to_output(encoder);
138 	struct drm_panel *panel = output->panel;
139 
140 	if (mode != DRM_MODE_DPMS_ON) {
141 		drm_panel_disable(panel);
142 		tegra_output_disable(output);
143 		drm_panel_unprepare(panel);
144 	} else {
145 		drm_panel_prepare(panel);
146 		tegra_output_enable(output);
147 		drm_panel_enable(panel);
148 	}
149 }
150 
151 static bool tegra_encoder_mode_fixup(struct drm_encoder *encoder,
152 				     const struct drm_display_mode *mode,
153 				     struct drm_display_mode *adjusted)
154 {
155 	return true;
156 }
157 
158 static void tegra_encoder_prepare(struct drm_encoder *encoder)
159 {
160 	tegra_encoder_dpms(encoder, DRM_MODE_DPMS_OFF);
161 }
162 
163 static void tegra_encoder_commit(struct drm_encoder *encoder)
164 {
165 	tegra_encoder_dpms(encoder, DRM_MODE_DPMS_ON);
166 }
167 
168 static void tegra_encoder_mode_set(struct drm_encoder *encoder,
169 				   struct drm_display_mode *mode,
170 				   struct drm_display_mode *adjusted)
171 {
172 }
173 
174 static const struct drm_encoder_helper_funcs encoder_helper_funcs = {
175 	.dpms = tegra_encoder_dpms,
176 	.mode_fixup = tegra_encoder_mode_fixup,
177 	.prepare = tegra_encoder_prepare,
178 	.commit = tegra_encoder_commit,
179 	.mode_set = tegra_encoder_mode_set,
180 };
181 
182 static irqreturn_t hpd_irq(int irq, void *data)
183 {
184 	struct tegra_output *output = data;
185 
186 	if (output->connector.dev)
187 		drm_helper_hpd_irq_event(output->connector.dev);
188 
189 	return IRQ_HANDLED;
190 }
191 
192 int tegra_output_probe(struct tegra_output *output)
193 {
194 	struct device_node *ddc, *panel;
195 	enum of_gpio_flags flags;
196 	int err, size;
197 
198 	if (!output->of_node)
199 		output->of_node = output->dev->of_node;
200 
201 	panel = of_parse_phandle(output->of_node, "nvidia,panel", 0);
202 	if (panel) {
203 		output->panel = of_drm_find_panel(panel);
204 		if (!output->panel)
205 			return -EPROBE_DEFER;
206 
207 		of_node_put(panel);
208 	}
209 
210 	output->edid = of_get_property(output->of_node, "nvidia,edid", &size);
211 
212 	ddc = of_parse_phandle(output->of_node, "nvidia,ddc-i2c-bus", 0);
213 	if (ddc) {
214 		output->ddc = of_find_i2c_adapter_by_node(ddc);
215 		if (!output->ddc) {
216 			err = -EPROBE_DEFER;
217 			of_node_put(ddc);
218 			return err;
219 		}
220 
221 		of_node_put(ddc);
222 	}
223 
224 	output->hpd_gpio = of_get_named_gpio_flags(output->of_node,
225 						   "nvidia,hpd-gpio", 0,
226 						   &flags);
227 	if (gpio_is_valid(output->hpd_gpio)) {
228 		unsigned long flags;
229 
230 		err = gpio_request_one(output->hpd_gpio, GPIOF_DIR_IN,
231 				       "HDMI hotplug detect");
232 		if (err < 0) {
233 			dev_err(output->dev, "gpio_request_one(): %d\n", err);
234 			return err;
235 		}
236 
237 		err = gpio_to_irq(output->hpd_gpio);
238 		if (err < 0) {
239 			dev_err(output->dev, "gpio_to_irq(): %d\n", err);
240 			gpio_free(output->hpd_gpio);
241 			return err;
242 		}
243 
244 		output->hpd_irq = err;
245 
246 		flags = IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING |
247 			IRQF_ONESHOT;
248 
249 		err = request_threaded_irq(output->hpd_irq, NULL, hpd_irq,
250 					   flags, "hpd", output);
251 		if (err < 0) {
252 			dev_err(output->dev, "failed to request IRQ#%u: %d\n",
253 				output->hpd_irq, err);
254 			gpio_free(output->hpd_gpio);
255 			return err;
256 		}
257 
258 		output->connector.polled = DRM_CONNECTOR_POLL_HPD;
259 
260 		/*
261 		 * Disable the interrupt until the connector has been
262 		 * initialized to avoid a race in the hotplug interrupt
263 		 * handler.
264 		 */
265 		disable_irq(output->hpd_irq);
266 	}
267 
268 	return 0;
269 }
270 
271 int tegra_output_remove(struct tegra_output *output)
272 {
273 	if (gpio_is_valid(output->hpd_gpio)) {
274 		free_irq(output->hpd_irq, output);
275 		gpio_free(output->hpd_gpio);
276 	}
277 
278 	if (output->ddc)
279 		put_device(&output->ddc->dev);
280 
281 	return 0;
282 }
283 
284 int tegra_output_init(struct drm_device *drm, struct tegra_output *output)
285 {
286 	int connector, encoder;
287 
288 	switch (output->type) {
289 	case TEGRA_OUTPUT_RGB:
290 		connector = DRM_MODE_CONNECTOR_LVDS;
291 		encoder = DRM_MODE_ENCODER_LVDS;
292 		break;
293 
294 	case TEGRA_OUTPUT_HDMI:
295 		connector = DRM_MODE_CONNECTOR_HDMIA;
296 		encoder = DRM_MODE_ENCODER_TMDS;
297 		break;
298 
299 	case TEGRA_OUTPUT_DSI:
300 		connector = DRM_MODE_CONNECTOR_DSI;
301 		encoder = DRM_MODE_ENCODER_DSI;
302 		break;
303 
304 	case TEGRA_OUTPUT_EDP:
305 		connector = DRM_MODE_CONNECTOR_eDP;
306 		encoder = DRM_MODE_ENCODER_TMDS;
307 		break;
308 
309 	default:
310 		connector = DRM_MODE_CONNECTOR_Unknown;
311 		encoder = DRM_MODE_ENCODER_NONE;
312 		break;
313 	}
314 
315 	drm_connector_init(drm, &output->connector, &connector_funcs,
316 			   connector);
317 	drm_connector_helper_add(&output->connector, &connector_helper_funcs);
318 	output->connector.dpms = DRM_MODE_DPMS_OFF;
319 
320 	if (output->panel)
321 		drm_panel_attach(output->panel, &output->connector);
322 
323 	drm_encoder_init(drm, &output->encoder, &encoder_funcs, encoder);
324 	drm_encoder_helper_add(&output->encoder, &encoder_helper_funcs);
325 
326 	drm_mode_connector_attach_encoder(&output->connector, &output->encoder);
327 	drm_connector_register(&output->connector);
328 
329 	output->encoder.possible_crtcs = 0x3;
330 
331 	/*
332 	 * The connector is now registered and ready to receive hotplug events
333 	 * so the hotplug interrupt can be enabled.
334 	 */
335 	if (gpio_is_valid(output->hpd_gpio))
336 		enable_irq(output->hpd_irq);
337 
338 	return 0;
339 }
340 
341 int tegra_output_exit(struct tegra_output *output)
342 {
343 	/*
344 	 * The connector is going away, so the interrupt must be disabled to
345 	 * prevent the hotplug interrupt handler from potentially crashing.
346 	 */
347 	if (gpio_is_valid(output->hpd_gpio))
348 		disable_irq(output->hpd_irq);
349 
350 	if (output->panel)
351 		drm_panel_detach(output->panel);
352 
353 	return 0;
354 }
355