xref: /openbmc/linux/drivers/gpu/drm/vc4/vc4_hdmi.c (revision 4f205687)
1 /*
2  * Copyright (C) 2015 Broadcom
3  * Copyright (c) 2014 The Linux Foundation. All rights reserved.
4  * Copyright (C) 2013 Red Hat
5  * Author: Rob Clark <robdclark@gmail.com>
6  *
7  * This program is free software; you can redistribute it and/or modify it
8  * under the terms of the GNU General Public License version 2 as published by
9  * the Free Software Foundation.
10  *
11  * This program is distributed in the hope that it will be useful, but WITHOUT
12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
14  * more details.
15  *
16  * You should have received a copy of the GNU General Public License along with
17  * this program.  If not, see <http://www.gnu.org/licenses/>.
18  */
19 
20 /**
21  * DOC: VC4 Falcon HDMI module
22  *
23  * The HDMI core has a state machine and a PHY.  Most of the unit
24  * operates off of the HSM clock from CPRMAN.  It also internally uses
25  * the PLLH_PIX clock for the PHY.
26  */
27 
28 #include "drm_atomic_helper.h"
29 #include "drm_crtc_helper.h"
30 #include "drm_edid.h"
31 #include "linux/clk.h"
32 #include "linux/component.h"
33 #include "linux/i2c.h"
34 #include "linux/of_gpio.h"
35 #include "linux/of_platform.h"
36 #include "vc4_drv.h"
37 #include "vc4_regs.h"
38 
39 /* General HDMI hardware state. */
40 struct vc4_hdmi {
41 	struct platform_device *pdev;
42 
43 	struct drm_encoder *encoder;
44 	struct drm_connector *connector;
45 
46 	struct i2c_adapter *ddc;
47 	void __iomem *hdmicore_regs;
48 	void __iomem *hd_regs;
49 	int hpd_gpio;
50 	bool hpd_active_low;
51 
52 	struct clk *pixel_clock;
53 	struct clk *hsm_clock;
54 };
55 
56 #define HDMI_READ(offset) readl(vc4->hdmi->hdmicore_regs + offset)
57 #define HDMI_WRITE(offset, val) writel(val, vc4->hdmi->hdmicore_regs + offset)
58 #define HD_READ(offset) readl(vc4->hdmi->hd_regs + offset)
59 #define HD_WRITE(offset, val) writel(val, vc4->hdmi->hd_regs + offset)
60 
61 /* VC4 HDMI encoder KMS struct */
62 struct vc4_hdmi_encoder {
63 	struct vc4_encoder base;
64 	bool hdmi_monitor;
65 };
66 
67 static inline struct vc4_hdmi_encoder *
68 to_vc4_hdmi_encoder(struct drm_encoder *encoder)
69 {
70 	return container_of(encoder, struct vc4_hdmi_encoder, base.base);
71 }
72 
73 /* VC4 HDMI connector KMS struct */
74 struct vc4_hdmi_connector {
75 	struct drm_connector base;
76 
77 	/* Since the connector is attached to just the one encoder,
78 	 * this is the reference to it so we can do the best_encoder()
79 	 * hook.
80 	 */
81 	struct drm_encoder *encoder;
82 };
83 
84 static inline struct vc4_hdmi_connector *
85 to_vc4_hdmi_connector(struct drm_connector *connector)
86 {
87 	return container_of(connector, struct vc4_hdmi_connector, base);
88 }
89 
90 #define HDMI_REG(reg) { reg, #reg }
91 static const struct {
92 	u32 reg;
93 	const char *name;
94 } hdmi_regs[] = {
95 	HDMI_REG(VC4_HDMI_CORE_REV),
96 	HDMI_REG(VC4_HDMI_SW_RESET_CONTROL),
97 	HDMI_REG(VC4_HDMI_HOTPLUG_INT),
98 	HDMI_REG(VC4_HDMI_HOTPLUG),
99 	HDMI_REG(VC4_HDMI_RAM_PACKET_CONFIG),
100 	HDMI_REG(VC4_HDMI_HORZA),
101 	HDMI_REG(VC4_HDMI_HORZB),
102 	HDMI_REG(VC4_HDMI_FIFO_CTL),
103 	HDMI_REG(VC4_HDMI_SCHEDULER_CONTROL),
104 	HDMI_REG(VC4_HDMI_VERTA0),
105 	HDMI_REG(VC4_HDMI_VERTA1),
106 	HDMI_REG(VC4_HDMI_VERTB0),
107 	HDMI_REG(VC4_HDMI_VERTB1),
108 	HDMI_REG(VC4_HDMI_TX_PHY_RESET_CTL),
109 };
110 
111 static const struct {
112 	u32 reg;
113 	const char *name;
114 } hd_regs[] = {
115 	HDMI_REG(VC4_HD_M_CTL),
116 	HDMI_REG(VC4_HD_MAI_CTL),
117 	HDMI_REG(VC4_HD_VID_CTL),
118 	HDMI_REG(VC4_HD_CSC_CTL),
119 	HDMI_REG(VC4_HD_FRAME_COUNT),
120 };
121 
122 #ifdef CONFIG_DEBUG_FS
123 int vc4_hdmi_debugfs_regs(struct seq_file *m, void *unused)
124 {
125 	struct drm_info_node *node = (struct drm_info_node *)m->private;
126 	struct drm_device *dev = node->minor->dev;
127 	struct vc4_dev *vc4 = to_vc4_dev(dev);
128 	int i;
129 
130 	for (i = 0; i < ARRAY_SIZE(hdmi_regs); i++) {
131 		seq_printf(m, "%s (0x%04x): 0x%08x\n",
132 			   hdmi_regs[i].name, hdmi_regs[i].reg,
133 			   HDMI_READ(hdmi_regs[i].reg));
134 	}
135 
136 	for (i = 0; i < ARRAY_SIZE(hd_regs); i++) {
137 		seq_printf(m, "%s (0x%04x): 0x%08x\n",
138 			   hd_regs[i].name, hd_regs[i].reg,
139 			   HD_READ(hd_regs[i].reg));
140 	}
141 
142 	return 0;
143 }
144 #endif /* CONFIG_DEBUG_FS */
145 
146 static void vc4_hdmi_dump_regs(struct drm_device *dev)
147 {
148 	struct vc4_dev *vc4 = to_vc4_dev(dev);
149 	int i;
150 
151 	for (i = 0; i < ARRAY_SIZE(hdmi_regs); i++) {
152 		DRM_INFO("0x%04x (%s): 0x%08x\n",
153 			 hdmi_regs[i].reg, hdmi_regs[i].name,
154 			 HDMI_READ(hdmi_regs[i].reg));
155 	}
156 	for (i = 0; i < ARRAY_SIZE(hd_regs); i++) {
157 		DRM_INFO("0x%04x (%s): 0x%08x\n",
158 			 hd_regs[i].reg, hd_regs[i].name,
159 			 HD_READ(hd_regs[i].reg));
160 	}
161 }
162 
163 static enum drm_connector_status
164 vc4_hdmi_connector_detect(struct drm_connector *connector, bool force)
165 {
166 	struct drm_device *dev = connector->dev;
167 	struct vc4_dev *vc4 = to_vc4_dev(dev);
168 
169 	if (vc4->hdmi->hpd_gpio) {
170 		if (gpio_get_value_cansleep(vc4->hdmi->hpd_gpio) ^
171 		    vc4->hdmi->hpd_active_low)
172 			return connector_status_connected;
173 		else
174 			return connector_status_disconnected;
175 	}
176 
177 	if (HDMI_READ(VC4_HDMI_HOTPLUG) & VC4_HDMI_HOTPLUG_CONNECTED)
178 		return connector_status_connected;
179 	else
180 		return connector_status_disconnected;
181 }
182 
183 static void vc4_hdmi_connector_destroy(struct drm_connector *connector)
184 {
185 	drm_connector_unregister(connector);
186 	drm_connector_cleanup(connector);
187 }
188 
189 static int vc4_hdmi_connector_get_modes(struct drm_connector *connector)
190 {
191 	struct vc4_hdmi_connector *vc4_connector =
192 		to_vc4_hdmi_connector(connector);
193 	struct drm_encoder *encoder = vc4_connector->encoder;
194 	struct vc4_hdmi_encoder *vc4_encoder = to_vc4_hdmi_encoder(encoder);
195 	struct drm_device *dev = connector->dev;
196 	struct vc4_dev *vc4 = to_vc4_dev(dev);
197 	int ret = 0;
198 	struct edid *edid;
199 
200 	edid = drm_get_edid(connector, vc4->hdmi->ddc);
201 	if (!edid)
202 		return -ENODEV;
203 
204 	vc4_encoder->hdmi_monitor = drm_detect_hdmi_monitor(edid);
205 	drm_mode_connector_update_edid_property(connector, edid);
206 	ret = drm_add_edid_modes(connector, edid);
207 
208 	return ret;
209 }
210 
211 static struct drm_encoder *
212 vc4_hdmi_connector_best_encoder(struct drm_connector *connector)
213 {
214 	struct vc4_hdmi_connector *hdmi_connector =
215 		to_vc4_hdmi_connector(connector);
216 	return hdmi_connector->encoder;
217 }
218 
219 static const struct drm_connector_funcs vc4_hdmi_connector_funcs = {
220 	.dpms = drm_atomic_helper_connector_dpms,
221 	.detect = vc4_hdmi_connector_detect,
222 	.fill_modes = drm_helper_probe_single_connector_modes,
223 	.destroy = vc4_hdmi_connector_destroy,
224 	.reset = drm_atomic_helper_connector_reset,
225 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
226 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
227 };
228 
229 static const struct drm_connector_helper_funcs vc4_hdmi_connector_helper_funcs = {
230 	.get_modes = vc4_hdmi_connector_get_modes,
231 	.best_encoder = vc4_hdmi_connector_best_encoder,
232 };
233 
234 static struct drm_connector *vc4_hdmi_connector_init(struct drm_device *dev,
235 						     struct drm_encoder *encoder)
236 {
237 	struct drm_connector *connector = NULL;
238 	struct vc4_hdmi_connector *hdmi_connector;
239 	int ret = 0;
240 
241 	hdmi_connector = devm_kzalloc(dev->dev, sizeof(*hdmi_connector),
242 				      GFP_KERNEL);
243 	if (!hdmi_connector) {
244 		ret = -ENOMEM;
245 		goto fail;
246 	}
247 	connector = &hdmi_connector->base;
248 
249 	hdmi_connector->encoder = encoder;
250 
251 	drm_connector_init(dev, connector, &vc4_hdmi_connector_funcs,
252 			   DRM_MODE_CONNECTOR_HDMIA);
253 	drm_connector_helper_add(connector, &vc4_hdmi_connector_helper_funcs);
254 
255 	connector->polled = (DRM_CONNECTOR_POLL_CONNECT |
256 			     DRM_CONNECTOR_POLL_DISCONNECT);
257 
258 	connector->interlace_allowed = 0;
259 	connector->doublescan_allowed = 0;
260 
261 	drm_mode_connector_attach_encoder(connector, encoder);
262 
263 	return connector;
264 
265  fail:
266 	if (connector)
267 		vc4_hdmi_connector_destroy(connector);
268 
269 	return ERR_PTR(ret);
270 }
271 
272 static void vc4_hdmi_encoder_destroy(struct drm_encoder *encoder)
273 {
274 	drm_encoder_cleanup(encoder);
275 }
276 
277 static const struct drm_encoder_funcs vc4_hdmi_encoder_funcs = {
278 	.destroy = vc4_hdmi_encoder_destroy,
279 };
280 
281 static void vc4_hdmi_encoder_mode_set(struct drm_encoder *encoder,
282 				      struct drm_display_mode *unadjusted_mode,
283 				      struct drm_display_mode *mode)
284 {
285 	struct drm_device *dev = encoder->dev;
286 	struct vc4_dev *vc4 = to_vc4_dev(dev);
287 	bool debug_dump_regs = false;
288 	bool hsync_pos = mode->flags & DRM_MODE_FLAG_PHSYNC;
289 	bool vsync_pos = mode->flags & DRM_MODE_FLAG_PVSYNC;
290 	u32 vactive = (mode->vdisplay >>
291 		       ((mode->flags & DRM_MODE_FLAG_INTERLACE) ? 1 : 0));
292 	u32 verta = (VC4_SET_FIELD(mode->vsync_end - mode->vsync_start,
293 				   VC4_HDMI_VERTA_VSP) |
294 		     VC4_SET_FIELD(mode->vsync_start - mode->vdisplay,
295 				   VC4_HDMI_VERTA_VFP) |
296 		     VC4_SET_FIELD(vactive, VC4_HDMI_VERTA_VAL));
297 	u32 vertb = (VC4_SET_FIELD(0, VC4_HDMI_VERTB_VSPO) |
298 		     VC4_SET_FIELD(mode->vtotal - mode->vsync_end,
299 				   VC4_HDMI_VERTB_VBP));
300 
301 	if (debug_dump_regs) {
302 		DRM_INFO("HDMI regs before:\n");
303 		vc4_hdmi_dump_regs(dev);
304 	}
305 
306 	HD_WRITE(VC4_HD_VID_CTL, 0);
307 
308 	clk_set_rate(vc4->hdmi->pixel_clock, mode->clock * 1000);
309 
310 	HDMI_WRITE(VC4_HDMI_SCHEDULER_CONTROL,
311 		   HDMI_READ(VC4_HDMI_SCHEDULER_CONTROL) |
312 		   VC4_HDMI_SCHEDULER_CONTROL_MANUAL_FORMAT |
313 		   VC4_HDMI_SCHEDULER_CONTROL_IGNORE_VSYNC_PREDICTS);
314 
315 	HDMI_WRITE(VC4_HDMI_HORZA,
316 		   (vsync_pos ? VC4_HDMI_HORZA_VPOS : 0) |
317 		   (hsync_pos ? VC4_HDMI_HORZA_HPOS : 0) |
318 		   VC4_SET_FIELD(mode->hdisplay, VC4_HDMI_HORZA_HAP));
319 
320 	HDMI_WRITE(VC4_HDMI_HORZB,
321 		   VC4_SET_FIELD(mode->htotal - mode->hsync_end,
322 				 VC4_HDMI_HORZB_HBP) |
323 		   VC4_SET_FIELD(mode->hsync_end - mode->hsync_start,
324 				 VC4_HDMI_HORZB_HSP) |
325 		   VC4_SET_FIELD(mode->hsync_start - mode->hdisplay,
326 				 VC4_HDMI_HORZB_HFP));
327 
328 	HDMI_WRITE(VC4_HDMI_VERTA0, verta);
329 	HDMI_WRITE(VC4_HDMI_VERTA1, verta);
330 
331 	HDMI_WRITE(VC4_HDMI_VERTB0, vertb);
332 	HDMI_WRITE(VC4_HDMI_VERTB1, vertb);
333 
334 	HD_WRITE(VC4_HD_VID_CTL,
335 		 (vsync_pos ? 0 : VC4_HD_VID_CTL_VSYNC_LOW) |
336 		 (hsync_pos ? 0 : VC4_HD_VID_CTL_HSYNC_LOW));
337 
338 	/* The RGB order applies even when CSC is disabled. */
339 	HD_WRITE(VC4_HD_CSC_CTL, VC4_SET_FIELD(VC4_HD_CSC_CTL_ORDER_BGR,
340 					       VC4_HD_CSC_CTL_ORDER));
341 
342 	HDMI_WRITE(VC4_HDMI_FIFO_CTL, VC4_HDMI_FIFO_CTL_MASTER_SLAVE_N);
343 
344 	if (debug_dump_regs) {
345 		DRM_INFO("HDMI regs after:\n");
346 		vc4_hdmi_dump_regs(dev);
347 	}
348 }
349 
350 static void vc4_hdmi_encoder_disable(struct drm_encoder *encoder)
351 {
352 	struct drm_device *dev = encoder->dev;
353 	struct vc4_dev *vc4 = to_vc4_dev(dev);
354 
355 	HDMI_WRITE(VC4_HDMI_TX_PHY_RESET_CTL, 0xf << 16);
356 	HD_WRITE(VC4_HD_VID_CTL,
357 		 HD_READ(VC4_HD_VID_CTL) & ~VC4_HD_VID_CTL_ENABLE);
358 }
359 
360 static void vc4_hdmi_encoder_enable(struct drm_encoder *encoder)
361 {
362 	struct vc4_hdmi_encoder *vc4_encoder = to_vc4_hdmi_encoder(encoder);
363 	struct drm_device *dev = encoder->dev;
364 	struct vc4_dev *vc4 = to_vc4_dev(dev);
365 	int ret;
366 
367 	HDMI_WRITE(VC4_HDMI_TX_PHY_RESET_CTL, 0);
368 
369 	HD_WRITE(VC4_HD_VID_CTL,
370 		 HD_READ(VC4_HD_VID_CTL) |
371 		 VC4_HD_VID_CTL_ENABLE |
372 		 VC4_HD_VID_CTL_UNDERFLOW_ENABLE |
373 		 VC4_HD_VID_CTL_FRAME_COUNTER_RESET);
374 
375 	if (vc4_encoder->hdmi_monitor) {
376 		HDMI_WRITE(VC4_HDMI_SCHEDULER_CONTROL,
377 			   HDMI_READ(VC4_HDMI_SCHEDULER_CONTROL) |
378 			   VC4_HDMI_SCHEDULER_CONTROL_MODE_HDMI);
379 
380 		ret = wait_for(HDMI_READ(VC4_HDMI_SCHEDULER_CONTROL) &
381 			       VC4_HDMI_SCHEDULER_CONTROL_HDMI_ACTIVE, 1);
382 		WARN_ONCE(ret, "Timeout waiting for "
383 			  "VC4_HDMI_SCHEDULER_CONTROL_HDMI_ACTIVE\n");
384 	} else {
385 		HDMI_WRITE(VC4_HDMI_RAM_PACKET_CONFIG,
386 			   HDMI_READ(VC4_HDMI_RAM_PACKET_CONFIG) &
387 			   ~(VC4_HDMI_RAM_PACKET_ENABLE));
388 		HDMI_WRITE(VC4_HDMI_SCHEDULER_CONTROL,
389 			   HDMI_READ(VC4_HDMI_SCHEDULER_CONTROL) &
390 			   ~VC4_HDMI_SCHEDULER_CONTROL_MODE_HDMI);
391 
392 		ret = wait_for(!(HDMI_READ(VC4_HDMI_SCHEDULER_CONTROL) &
393 				 VC4_HDMI_SCHEDULER_CONTROL_HDMI_ACTIVE), 1);
394 		WARN_ONCE(ret, "Timeout waiting for "
395 			  "!VC4_HDMI_SCHEDULER_CONTROL_HDMI_ACTIVE\n");
396 	}
397 
398 	if (vc4_encoder->hdmi_monitor) {
399 		u32 drift;
400 
401 		WARN_ON(!(HDMI_READ(VC4_HDMI_SCHEDULER_CONTROL) &
402 			  VC4_HDMI_SCHEDULER_CONTROL_HDMI_ACTIVE));
403 		HDMI_WRITE(VC4_HDMI_SCHEDULER_CONTROL,
404 			   HDMI_READ(VC4_HDMI_SCHEDULER_CONTROL) |
405 			   VC4_HDMI_SCHEDULER_CONTROL_VERT_ALWAYS_KEEPOUT);
406 
407 		/* XXX: Set HDMI_RAM_PACKET_CONFIG (1 << 16) and set
408 		 * up the infoframe.
409 		 */
410 
411 		drift = HDMI_READ(VC4_HDMI_FIFO_CTL);
412 		drift &= VC4_HDMI_FIFO_VALID_WRITE_MASK;
413 
414 		HDMI_WRITE(VC4_HDMI_FIFO_CTL,
415 			   drift & ~VC4_HDMI_FIFO_CTL_RECENTER);
416 		HDMI_WRITE(VC4_HDMI_FIFO_CTL,
417 			   drift | VC4_HDMI_FIFO_CTL_RECENTER);
418 		udelay(1000);
419 		HDMI_WRITE(VC4_HDMI_FIFO_CTL,
420 			   drift & ~VC4_HDMI_FIFO_CTL_RECENTER);
421 		HDMI_WRITE(VC4_HDMI_FIFO_CTL,
422 			   drift | VC4_HDMI_FIFO_CTL_RECENTER);
423 
424 		ret = wait_for(HDMI_READ(VC4_HDMI_FIFO_CTL) &
425 			       VC4_HDMI_FIFO_CTL_RECENTER_DONE, 1);
426 		WARN_ONCE(ret, "Timeout waiting for "
427 			  "VC4_HDMI_FIFO_CTL_RECENTER_DONE");
428 	}
429 }
430 
431 static const struct drm_encoder_helper_funcs vc4_hdmi_encoder_helper_funcs = {
432 	.mode_set = vc4_hdmi_encoder_mode_set,
433 	.disable = vc4_hdmi_encoder_disable,
434 	.enable = vc4_hdmi_encoder_enable,
435 };
436 
437 static int vc4_hdmi_bind(struct device *dev, struct device *master, void *data)
438 {
439 	struct platform_device *pdev = to_platform_device(dev);
440 	struct drm_device *drm = dev_get_drvdata(master);
441 	struct vc4_dev *vc4 = drm->dev_private;
442 	struct vc4_hdmi *hdmi;
443 	struct vc4_hdmi_encoder *vc4_hdmi_encoder;
444 	struct device_node *ddc_node;
445 	u32 value;
446 	int ret;
447 
448 	hdmi = devm_kzalloc(dev, sizeof(*hdmi), GFP_KERNEL);
449 	if (!hdmi)
450 		return -ENOMEM;
451 
452 	vc4_hdmi_encoder = devm_kzalloc(dev, sizeof(*vc4_hdmi_encoder),
453 					GFP_KERNEL);
454 	if (!vc4_hdmi_encoder)
455 		return -ENOMEM;
456 	vc4_hdmi_encoder->base.type = VC4_ENCODER_TYPE_HDMI;
457 	hdmi->encoder = &vc4_hdmi_encoder->base.base;
458 
459 	hdmi->pdev = pdev;
460 	hdmi->hdmicore_regs = vc4_ioremap_regs(pdev, 0);
461 	if (IS_ERR(hdmi->hdmicore_regs))
462 		return PTR_ERR(hdmi->hdmicore_regs);
463 
464 	hdmi->hd_regs = vc4_ioremap_regs(pdev, 1);
465 	if (IS_ERR(hdmi->hd_regs))
466 		return PTR_ERR(hdmi->hd_regs);
467 
468 	ddc_node = of_parse_phandle(dev->of_node, "ddc", 0);
469 	if (!ddc_node) {
470 		DRM_ERROR("Failed to find ddc node in device tree\n");
471 		return -ENODEV;
472 	}
473 
474 	hdmi->pixel_clock = devm_clk_get(dev, "pixel");
475 	if (IS_ERR(hdmi->pixel_clock)) {
476 		DRM_ERROR("Failed to get pixel clock\n");
477 		return PTR_ERR(hdmi->pixel_clock);
478 	}
479 	hdmi->hsm_clock = devm_clk_get(dev, "hdmi");
480 	if (IS_ERR(hdmi->hsm_clock)) {
481 		DRM_ERROR("Failed to get HDMI state machine clock\n");
482 		return PTR_ERR(hdmi->hsm_clock);
483 	}
484 
485 	hdmi->ddc = of_find_i2c_adapter_by_node(ddc_node);
486 	if (!hdmi->ddc) {
487 		DRM_DEBUG("Failed to get ddc i2c adapter by node\n");
488 		return -EPROBE_DEFER;
489 	}
490 
491 	/* Enable the clocks at startup.  We can't quite recover from
492 	 * turning off the pixel clock during disable/enables yet, so
493 	 * it's always running.
494 	 */
495 	ret = clk_prepare_enable(hdmi->pixel_clock);
496 	if (ret) {
497 		DRM_ERROR("Failed to turn on pixel clock: %d\n", ret);
498 		goto err_put_i2c;
499 	}
500 
501 	/* This is the rate that is set by the firmware.  The number
502 	 * needs to be a bit higher than the pixel clock rate
503 	 * (generally 148.5Mhz).
504 	 */
505 	ret = clk_set_rate(hdmi->hsm_clock, 163682864);
506 	if (ret) {
507 		DRM_ERROR("Failed to set HSM clock rate: %d\n", ret);
508 		goto err_unprepare_pix;
509 	}
510 
511 	ret = clk_prepare_enable(hdmi->hsm_clock);
512 	if (ret) {
513 		DRM_ERROR("Failed to turn on HDMI state machine clock: %d\n",
514 			  ret);
515 		goto err_unprepare_pix;
516 	}
517 
518 	/* Only use the GPIO HPD pin if present in the DT, otherwise
519 	 * we'll use the HDMI core's register.
520 	 */
521 	if (of_find_property(dev->of_node, "hpd-gpios", &value)) {
522 		enum of_gpio_flags hpd_gpio_flags;
523 
524 		hdmi->hpd_gpio = of_get_named_gpio_flags(dev->of_node,
525 							 "hpd-gpios", 0,
526 							 &hpd_gpio_flags);
527 		if (hdmi->hpd_gpio < 0) {
528 			ret = hdmi->hpd_gpio;
529 			goto err_unprepare_hsm;
530 		}
531 
532 		hdmi->hpd_active_low = hpd_gpio_flags & OF_GPIO_ACTIVE_LOW;
533 	}
534 
535 	vc4->hdmi = hdmi;
536 
537 	/* HDMI core must be enabled. */
538 	if (!(HD_READ(VC4_HD_M_CTL) & VC4_HD_M_ENABLE)) {
539 		HD_WRITE(VC4_HD_M_CTL, VC4_HD_M_SW_RST);
540 		udelay(1);
541 		HD_WRITE(VC4_HD_M_CTL, 0);
542 
543 		HD_WRITE(VC4_HD_M_CTL, VC4_HD_M_ENABLE);
544 
545 		HDMI_WRITE(VC4_HDMI_SW_RESET_CONTROL,
546 			   VC4_HDMI_SW_RESET_HDMI |
547 			   VC4_HDMI_SW_RESET_FORMAT_DETECT);
548 
549 		HDMI_WRITE(VC4_HDMI_SW_RESET_CONTROL, 0);
550 
551 		/* PHY should be in reset, like
552 		 * vc4_hdmi_encoder_disable() does.
553 		 */
554 		HDMI_WRITE(VC4_HDMI_TX_PHY_RESET_CTL, 0xf << 16);
555 	}
556 
557 	drm_encoder_init(drm, hdmi->encoder, &vc4_hdmi_encoder_funcs,
558 			 DRM_MODE_ENCODER_TMDS, NULL);
559 	drm_encoder_helper_add(hdmi->encoder, &vc4_hdmi_encoder_helper_funcs);
560 
561 	hdmi->connector = vc4_hdmi_connector_init(drm, hdmi->encoder);
562 	if (IS_ERR(hdmi->connector)) {
563 		ret = PTR_ERR(hdmi->connector);
564 		goto err_destroy_encoder;
565 	}
566 
567 	return 0;
568 
569 err_destroy_encoder:
570 	vc4_hdmi_encoder_destroy(hdmi->encoder);
571 err_unprepare_hsm:
572 	clk_disable_unprepare(hdmi->hsm_clock);
573 err_unprepare_pix:
574 	clk_disable_unprepare(hdmi->pixel_clock);
575 err_put_i2c:
576 	put_device(&hdmi->ddc->dev);
577 
578 	return ret;
579 }
580 
581 static void vc4_hdmi_unbind(struct device *dev, struct device *master,
582 			    void *data)
583 {
584 	struct drm_device *drm = dev_get_drvdata(master);
585 	struct vc4_dev *vc4 = drm->dev_private;
586 	struct vc4_hdmi *hdmi = vc4->hdmi;
587 
588 	vc4_hdmi_connector_destroy(hdmi->connector);
589 	vc4_hdmi_encoder_destroy(hdmi->encoder);
590 
591 	clk_disable_unprepare(hdmi->pixel_clock);
592 	clk_disable_unprepare(hdmi->hsm_clock);
593 	put_device(&hdmi->ddc->dev);
594 
595 	vc4->hdmi = NULL;
596 }
597 
598 static const struct component_ops vc4_hdmi_ops = {
599 	.bind   = vc4_hdmi_bind,
600 	.unbind = vc4_hdmi_unbind,
601 };
602 
603 static int vc4_hdmi_dev_probe(struct platform_device *pdev)
604 {
605 	return component_add(&pdev->dev, &vc4_hdmi_ops);
606 }
607 
608 static int vc4_hdmi_dev_remove(struct platform_device *pdev)
609 {
610 	component_del(&pdev->dev, &vc4_hdmi_ops);
611 	return 0;
612 }
613 
614 static const struct of_device_id vc4_hdmi_dt_match[] = {
615 	{ .compatible = "brcm,bcm2835-hdmi" },
616 	{}
617 };
618 
619 struct platform_driver vc4_hdmi_driver = {
620 	.probe = vc4_hdmi_dev_probe,
621 	.remove = vc4_hdmi_dev_remove,
622 	.driver = {
623 		.name = "vc4_hdmi",
624 		.of_match_table = vc4_hdmi_dt_match,
625 	},
626 };
627