xref: /linux/drivers/gpu/drm/sun4i/sun4i_tcon.c (revision 1517d90cfafe0f95fd7863d04e1596f7beb7dfa8)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (C) 2015 Free Electrons
4  * Copyright (C) 2015 NextThing Co
5  *
6  * Maxime Ripard <maxime.ripard@free-electrons.com>
7  */
8 
9 #include <linux/component.h>
10 #include <linux/ioport.h>
11 #include <linux/module.h>
12 #include <linux/of_address.h>
13 #include <linux/of_device.h>
14 #include <linux/of_irq.h>
15 #include <linux/regmap.h>
16 #include <linux/reset.h>
17 
18 #include <drm/drm_atomic_helper.h>
19 #include <drm/drm_connector.h>
20 #include <drm/drm_crtc.h>
21 #include <drm/drm_encoder.h>
22 #include <drm/drm_modes.h>
23 #include <drm/drm_of.h>
24 #include <drm/drm_panel.h>
25 #include <drm/drm_print.h>
26 #include <drm/drm_probe_helper.h>
27 #include <drm/drm_vblank.h>
28 
29 #include <uapi/drm/drm_mode.h>
30 
31 #include "sun4i_crtc.h"
32 #include "sun4i_dotclock.h"
33 #include "sun4i_drv.h"
34 #include "sun4i_lvds.h"
35 #include "sun4i_rgb.h"
36 #include "sun4i_tcon.h"
37 #include "sun6i_mipi_dsi.h"
38 #include "sun8i_tcon_top.h"
39 #include "sunxi_engine.h"
40 
41 static struct drm_connector *sun4i_tcon_get_connector(const struct drm_encoder *encoder)
42 {
43 	struct drm_connector *connector;
44 	struct drm_connector_list_iter iter;
45 
46 	drm_connector_list_iter_begin(encoder->dev, &iter);
47 	drm_for_each_connector_iter(connector, &iter)
48 		if (connector->encoder == encoder) {
49 			drm_connector_list_iter_end(&iter);
50 			return connector;
51 		}
52 	drm_connector_list_iter_end(&iter);
53 
54 	return NULL;
55 }
56 
57 static int sun4i_tcon_get_pixel_depth(const struct drm_encoder *encoder)
58 {
59 	struct drm_connector *connector;
60 	struct drm_display_info *info;
61 
62 	connector = sun4i_tcon_get_connector(encoder);
63 	if (!connector)
64 		return -EINVAL;
65 
66 	info = &connector->display_info;
67 	if (info->num_bus_formats != 1)
68 		return -EINVAL;
69 
70 	switch (info->bus_formats[0]) {
71 	case MEDIA_BUS_FMT_RGB666_1X7X3_SPWG:
72 		return 18;
73 
74 	case MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA:
75 	case MEDIA_BUS_FMT_RGB888_1X7X4_SPWG:
76 		return 24;
77 	}
78 
79 	return -EINVAL;
80 }
81 
82 static void sun4i_tcon_channel_set_status(struct sun4i_tcon *tcon, int channel,
83 					  bool enabled)
84 {
85 	struct clk *clk;
86 
87 	switch (channel) {
88 	case 0:
89 		WARN_ON(!tcon->quirks->has_channel_0);
90 		regmap_update_bits(tcon->regs, SUN4I_TCON0_CTL_REG,
91 				   SUN4I_TCON0_CTL_TCON_ENABLE,
92 				   enabled ? SUN4I_TCON0_CTL_TCON_ENABLE : 0);
93 		clk = tcon->dclk;
94 		break;
95 	case 1:
96 		WARN_ON(!tcon->quirks->has_channel_1);
97 		regmap_update_bits(tcon->regs, SUN4I_TCON1_CTL_REG,
98 				   SUN4I_TCON1_CTL_TCON_ENABLE,
99 				   enabled ? SUN4I_TCON1_CTL_TCON_ENABLE : 0);
100 		clk = tcon->sclk1;
101 		break;
102 	default:
103 		DRM_WARN("Unknown channel... doing nothing\n");
104 		return;
105 	}
106 
107 	if (enabled) {
108 		clk_prepare_enable(clk);
109 		clk_rate_exclusive_get(clk);
110 	} else {
111 		clk_rate_exclusive_put(clk);
112 		clk_disable_unprepare(clk);
113 	}
114 }
115 
116 static void sun4i_tcon_lvds_set_status(struct sun4i_tcon *tcon,
117 				       const struct drm_encoder *encoder,
118 				       bool enabled)
119 {
120 	if (enabled) {
121 		u8 val;
122 
123 		regmap_update_bits(tcon->regs, SUN4I_TCON0_LVDS_IF_REG,
124 				   SUN4I_TCON0_LVDS_IF_EN,
125 				   SUN4I_TCON0_LVDS_IF_EN);
126 
127 		/*
128 		 * As their name suggest, these values only apply to the A31
129 		 * and later SoCs. We'll have to rework this when merging
130 		 * support for the older SoCs.
131 		 */
132 		regmap_write(tcon->regs, SUN4I_TCON0_LVDS_ANA0_REG,
133 			     SUN6I_TCON0_LVDS_ANA0_C(2) |
134 			     SUN6I_TCON0_LVDS_ANA0_V(3) |
135 			     SUN6I_TCON0_LVDS_ANA0_PD(2) |
136 			     SUN6I_TCON0_LVDS_ANA0_EN_LDO);
137 		udelay(2);
138 
139 		regmap_update_bits(tcon->regs, SUN4I_TCON0_LVDS_ANA0_REG,
140 				   SUN6I_TCON0_LVDS_ANA0_EN_MB,
141 				   SUN6I_TCON0_LVDS_ANA0_EN_MB);
142 		udelay(2);
143 
144 		regmap_update_bits(tcon->regs, SUN4I_TCON0_LVDS_ANA0_REG,
145 				   SUN6I_TCON0_LVDS_ANA0_EN_DRVC,
146 				   SUN6I_TCON0_LVDS_ANA0_EN_DRVC);
147 
148 		if (sun4i_tcon_get_pixel_depth(encoder) == 18)
149 			val = 7;
150 		else
151 			val = 0xf;
152 
153 		regmap_write_bits(tcon->regs, SUN4I_TCON0_LVDS_ANA0_REG,
154 				  SUN6I_TCON0_LVDS_ANA0_EN_DRVD(0xf),
155 				  SUN6I_TCON0_LVDS_ANA0_EN_DRVD(val));
156 	} else {
157 		regmap_update_bits(tcon->regs, SUN4I_TCON0_LVDS_IF_REG,
158 				   SUN4I_TCON0_LVDS_IF_EN, 0);
159 	}
160 }
161 
162 void sun4i_tcon_set_status(struct sun4i_tcon *tcon,
163 			   const struct drm_encoder *encoder,
164 			   bool enabled)
165 {
166 	bool is_lvds = false;
167 	int channel;
168 
169 	switch (encoder->encoder_type) {
170 	case DRM_MODE_ENCODER_LVDS:
171 		is_lvds = true;
172 		/* Fallthrough */
173 	case DRM_MODE_ENCODER_DSI:
174 	case DRM_MODE_ENCODER_NONE:
175 		channel = 0;
176 		break;
177 	case DRM_MODE_ENCODER_TMDS:
178 	case DRM_MODE_ENCODER_TVDAC:
179 		channel = 1;
180 		break;
181 	default:
182 		DRM_DEBUG_DRIVER("Unknown encoder type, doing nothing...\n");
183 		return;
184 	}
185 
186 	if (is_lvds && !enabled)
187 		sun4i_tcon_lvds_set_status(tcon, encoder, false);
188 
189 	regmap_update_bits(tcon->regs, SUN4I_TCON_GCTL_REG,
190 			   SUN4I_TCON_GCTL_TCON_ENABLE,
191 			   enabled ? SUN4I_TCON_GCTL_TCON_ENABLE : 0);
192 
193 	if (is_lvds && enabled)
194 		sun4i_tcon_lvds_set_status(tcon, encoder, true);
195 
196 	sun4i_tcon_channel_set_status(tcon, channel, enabled);
197 }
198 
199 void sun4i_tcon_enable_vblank(struct sun4i_tcon *tcon, bool enable)
200 {
201 	u32 mask, val = 0;
202 
203 	DRM_DEBUG_DRIVER("%sabling VBLANK interrupt\n", enable ? "En" : "Dis");
204 
205 	mask = SUN4I_TCON_GINT0_VBLANK_ENABLE(0) |
206 		SUN4I_TCON_GINT0_VBLANK_ENABLE(1) |
207 		SUN4I_TCON_GINT0_TCON0_TRI_FINISH_ENABLE;
208 
209 	if (enable)
210 		val = mask;
211 
212 	regmap_update_bits(tcon->regs, SUN4I_TCON_GINT0_REG, mask, val);
213 }
214 EXPORT_SYMBOL(sun4i_tcon_enable_vblank);
215 
216 /*
217  * This function is a helper for TCON output muxing. The TCON output
218  * muxing control register in earlier SoCs (without the TCON TOP block)
219  * are located in TCON0. This helper returns a pointer to TCON0's
220  * sun4i_tcon structure, or NULL if not found.
221  */
222 static struct sun4i_tcon *sun4i_get_tcon0(struct drm_device *drm)
223 {
224 	struct sun4i_drv *drv = drm->dev_private;
225 	struct sun4i_tcon *tcon;
226 
227 	list_for_each_entry(tcon, &drv->tcon_list, list)
228 		if (tcon->id == 0)
229 			return tcon;
230 
231 	dev_warn(drm->dev,
232 		 "TCON0 not found, display output muxing may not work\n");
233 
234 	return NULL;
235 }
236 
237 static void sun4i_tcon_set_mux(struct sun4i_tcon *tcon, int channel,
238 			       const struct drm_encoder *encoder)
239 {
240 	int ret = -ENOTSUPP;
241 
242 	if (tcon->quirks->set_mux)
243 		ret = tcon->quirks->set_mux(tcon, encoder);
244 
245 	DRM_DEBUG_DRIVER("Muxing encoder %s to CRTC %s: %d\n",
246 			 encoder->name, encoder->crtc->name, ret);
247 }
248 
249 static int sun4i_tcon_get_clk_delay(const struct drm_display_mode *mode,
250 				    int channel)
251 {
252 	int delay = mode->vtotal - mode->vdisplay;
253 
254 	if (mode->flags & DRM_MODE_FLAG_INTERLACE)
255 		delay /= 2;
256 
257 	if (channel == 1)
258 		delay -= 2;
259 
260 	delay = min(delay, 30);
261 
262 	DRM_DEBUG_DRIVER("TCON %d clock delay %u\n", channel, delay);
263 
264 	return delay;
265 }
266 
267 static void sun4i_tcon0_mode_set_common(struct sun4i_tcon *tcon,
268 					const struct drm_display_mode *mode)
269 {
270 	/* Configure the dot clock */
271 	clk_set_rate(tcon->dclk, mode->crtc_clock * 1000);
272 
273 	/* Set the resolution */
274 	regmap_write(tcon->regs, SUN4I_TCON0_BASIC0_REG,
275 		     SUN4I_TCON0_BASIC0_X(mode->crtc_hdisplay) |
276 		     SUN4I_TCON0_BASIC0_Y(mode->crtc_vdisplay));
277 }
278 
279 static void sun4i_tcon0_mode_set_dithering(struct sun4i_tcon *tcon,
280 					   const struct drm_connector *connector)
281 {
282 	u32 bus_format = 0;
283 	u32 val = 0;
284 
285 	/* XXX Would this ever happen? */
286 	if (!connector)
287 		return;
288 
289 	/*
290 	 * FIXME: Undocumented bits
291 	 *
292 	 * The whole dithering process and these parameters are not
293 	 * explained in the vendor documents or BSP kernel code.
294 	 */
295 	regmap_write(tcon->regs, SUN4I_TCON0_FRM_SEED_PR_REG, 0x11111111);
296 	regmap_write(tcon->regs, SUN4I_TCON0_FRM_SEED_PG_REG, 0x11111111);
297 	regmap_write(tcon->regs, SUN4I_TCON0_FRM_SEED_PB_REG, 0x11111111);
298 	regmap_write(tcon->regs, SUN4I_TCON0_FRM_SEED_LR_REG, 0x11111111);
299 	regmap_write(tcon->regs, SUN4I_TCON0_FRM_SEED_LG_REG, 0x11111111);
300 	regmap_write(tcon->regs, SUN4I_TCON0_FRM_SEED_LB_REG, 0x11111111);
301 	regmap_write(tcon->regs, SUN4I_TCON0_FRM_TBL0_REG, 0x01010000);
302 	regmap_write(tcon->regs, SUN4I_TCON0_FRM_TBL1_REG, 0x15151111);
303 	regmap_write(tcon->regs, SUN4I_TCON0_FRM_TBL2_REG, 0x57575555);
304 	regmap_write(tcon->regs, SUN4I_TCON0_FRM_TBL3_REG, 0x7f7f7777);
305 
306 	/* Do dithering if panel only supports 6 bits per color */
307 	if (connector->display_info.bpc == 6)
308 		val |= SUN4I_TCON0_FRM_CTL_EN;
309 
310 	if (connector->display_info.num_bus_formats == 1)
311 		bus_format = connector->display_info.bus_formats[0];
312 
313 	/* Check the connection format */
314 	switch (bus_format) {
315 	case MEDIA_BUS_FMT_RGB565_1X16:
316 		/* R and B components are only 5 bits deep */
317 		val |= SUN4I_TCON0_FRM_CTL_MODE_R;
318 		val |= SUN4I_TCON0_FRM_CTL_MODE_B;
319 		/* Fall through */
320 	case MEDIA_BUS_FMT_RGB666_1X18:
321 	case MEDIA_BUS_FMT_RGB666_1X7X3_SPWG:
322 		/* Fall through: enable dithering */
323 		val |= SUN4I_TCON0_FRM_CTL_EN;
324 		break;
325 	}
326 
327 	/* Write dithering settings */
328 	regmap_write(tcon->regs, SUN4I_TCON_FRM_CTL_REG, val);
329 }
330 
331 static void sun4i_tcon0_mode_set_cpu(struct sun4i_tcon *tcon,
332 				     const struct drm_encoder *encoder,
333 				     const struct drm_display_mode *mode)
334 {
335 	/* TODO support normal CPU interface modes */
336 	struct sun6i_dsi *dsi = encoder_to_sun6i_dsi(encoder);
337 	struct mipi_dsi_device *device = dsi->device;
338 	u8 bpp = mipi_dsi_pixel_format_to_bpp(device->format);
339 	u8 lanes = device->lanes;
340 	u32 block_space, start_delay;
341 	u32 tcon_div;
342 
343 	tcon->dclk_min_div = SUN6I_DSI_TCON_DIV;
344 	tcon->dclk_max_div = SUN6I_DSI_TCON_DIV;
345 
346 	sun4i_tcon0_mode_set_common(tcon, mode);
347 
348 	/* Set dithering if needed */
349 	sun4i_tcon0_mode_set_dithering(tcon, sun4i_tcon_get_connector(encoder));
350 
351 	regmap_update_bits(tcon->regs, SUN4I_TCON0_CTL_REG,
352 			   SUN4I_TCON0_CTL_IF_MASK,
353 			   SUN4I_TCON0_CTL_IF_8080);
354 
355 	regmap_write(tcon->regs, SUN4I_TCON_ECC_FIFO_REG,
356 		     SUN4I_TCON_ECC_FIFO_EN);
357 
358 	regmap_write(tcon->regs, SUN4I_TCON0_CPU_IF_REG,
359 		     SUN4I_TCON0_CPU_IF_MODE_DSI |
360 		     SUN4I_TCON0_CPU_IF_TRI_FIFO_FLUSH |
361 		     SUN4I_TCON0_CPU_IF_TRI_FIFO_EN |
362 		     SUN4I_TCON0_CPU_IF_TRI_EN);
363 
364 	/*
365 	 * This looks suspicious, but it works...
366 	 *
367 	 * The datasheet says that this should be set higher than 20 *
368 	 * pixel cycle, but it's not clear what a pixel cycle is.
369 	 */
370 	regmap_read(tcon->regs, SUN4I_TCON0_DCLK_REG, &tcon_div);
371 	tcon_div &= GENMASK(6, 0);
372 	block_space = mode->htotal * bpp / (tcon_div * lanes);
373 	block_space -= mode->hdisplay + 40;
374 
375 	regmap_write(tcon->regs, SUN4I_TCON0_CPU_TRI0_REG,
376 		     SUN4I_TCON0_CPU_TRI0_BLOCK_SPACE(block_space) |
377 		     SUN4I_TCON0_CPU_TRI0_BLOCK_SIZE(mode->hdisplay));
378 
379 	regmap_write(tcon->regs, SUN4I_TCON0_CPU_TRI1_REG,
380 		     SUN4I_TCON0_CPU_TRI1_BLOCK_NUM(mode->vdisplay));
381 
382 	start_delay = (mode->crtc_vtotal - mode->crtc_vdisplay - 10 - 1);
383 	start_delay = start_delay * mode->crtc_htotal * 149;
384 	start_delay = start_delay / (mode->crtc_clock / 1000) / 8;
385 	regmap_write(tcon->regs, SUN4I_TCON0_CPU_TRI2_REG,
386 		     SUN4I_TCON0_CPU_TRI2_TRANS_START_SET(10) |
387 		     SUN4I_TCON0_CPU_TRI2_START_DELAY(start_delay));
388 
389 	/*
390 	 * The Allwinner BSP has a comment that the period should be
391 	 * the display clock * 15, but uses an hardcoded 3000...
392 	 */
393 	regmap_write(tcon->regs, SUN4I_TCON_SAFE_PERIOD_REG,
394 		     SUN4I_TCON_SAFE_PERIOD_NUM(3000) |
395 		     SUN4I_TCON_SAFE_PERIOD_MODE(3));
396 
397 	/* Enable the output on the pins */
398 	regmap_write(tcon->regs, SUN4I_TCON0_IO_TRI_REG,
399 		     0xe0000000);
400 }
401 
402 static void sun4i_tcon0_mode_set_lvds(struct sun4i_tcon *tcon,
403 				      const struct drm_encoder *encoder,
404 				      const struct drm_display_mode *mode)
405 {
406 	unsigned int bp;
407 	u8 clk_delay;
408 	u32 reg, val = 0;
409 
410 	WARN_ON(!tcon->quirks->has_channel_0);
411 
412 	tcon->dclk_min_div = 7;
413 	tcon->dclk_max_div = 7;
414 	sun4i_tcon0_mode_set_common(tcon, mode);
415 
416 	/* Set dithering if needed */
417 	sun4i_tcon0_mode_set_dithering(tcon, sun4i_tcon_get_connector(encoder));
418 
419 	/* Adjust clock delay */
420 	clk_delay = sun4i_tcon_get_clk_delay(mode, 0);
421 	regmap_update_bits(tcon->regs, SUN4I_TCON0_CTL_REG,
422 			   SUN4I_TCON0_CTL_CLK_DELAY_MASK,
423 			   SUN4I_TCON0_CTL_CLK_DELAY(clk_delay));
424 
425 	/*
426 	 * This is called a backporch in the register documentation,
427 	 * but it really is the back porch + hsync
428 	 */
429 	bp = mode->crtc_htotal - mode->crtc_hsync_start;
430 	DRM_DEBUG_DRIVER("Setting horizontal total %d, backporch %d\n",
431 			 mode->crtc_htotal, bp);
432 
433 	/* Set horizontal display timings */
434 	regmap_write(tcon->regs, SUN4I_TCON0_BASIC1_REG,
435 		     SUN4I_TCON0_BASIC1_H_TOTAL(mode->htotal) |
436 		     SUN4I_TCON0_BASIC1_H_BACKPORCH(bp));
437 
438 	/*
439 	 * This is called a backporch in the register documentation,
440 	 * but it really is the back porch + hsync
441 	 */
442 	bp = mode->crtc_vtotal - mode->crtc_vsync_start;
443 	DRM_DEBUG_DRIVER("Setting vertical total %d, backporch %d\n",
444 			 mode->crtc_vtotal, bp);
445 
446 	/* Set vertical display timings */
447 	regmap_write(tcon->regs, SUN4I_TCON0_BASIC2_REG,
448 		     SUN4I_TCON0_BASIC2_V_TOTAL(mode->crtc_vtotal * 2) |
449 		     SUN4I_TCON0_BASIC2_V_BACKPORCH(bp));
450 
451 	reg = SUN4I_TCON0_LVDS_IF_CLK_SEL_TCON0 |
452 		SUN4I_TCON0_LVDS_IF_DATA_POL_NORMAL |
453 		SUN4I_TCON0_LVDS_IF_CLK_POL_NORMAL;
454 	if (sun4i_tcon_get_pixel_depth(encoder) == 24)
455 		reg |= SUN4I_TCON0_LVDS_IF_BITWIDTH_24BITS;
456 	else
457 		reg |= SUN4I_TCON0_LVDS_IF_BITWIDTH_18BITS;
458 
459 	regmap_write(tcon->regs, SUN4I_TCON0_LVDS_IF_REG, reg);
460 
461 	/* Setup the polarity of the various signals */
462 	if (!(mode->flags & DRM_MODE_FLAG_PHSYNC))
463 		val |= SUN4I_TCON0_IO_POL_HSYNC_POSITIVE;
464 
465 	if (!(mode->flags & DRM_MODE_FLAG_PVSYNC))
466 		val |= SUN4I_TCON0_IO_POL_VSYNC_POSITIVE;
467 
468 	regmap_write(tcon->regs, SUN4I_TCON0_IO_POL_REG, val);
469 
470 	/* Map output pins to channel 0 */
471 	regmap_update_bits(tcon->regs, SUN4I_TCON_GCTL_REG,
472 			   SUN4I_TCON_GCTL_IOMAP_MASK,
473 			   SUN4I_TCON_GCTL_IOMAP_TCON0);
474 
475 	/* Enable the output on the pins */
476 	regmap_write(tcon->regs, SUN4I_TCON0_IO_TRI_REG, 0xe0000000);
477 }
478 
479 static void sun4i_tcon0_mode_set_rgb(struct sun4i_tcon *tcon,
480 				     const struct drm_encoder *encoder,
481 				     const struct drm_display_mode *mode)
482 {
483 	struct drm_connector *connector = sun4i_tcon_get_connector(encoder);
484 	const struct drm_display_info *info = &connector->display_info;
485 	unsigned int bp, hsync, vsync;
486 	u8 clk_delay;
487 	u32 val = 0;
488 
489 	WARN_ON(!tcon->quirks->has_channel_0);
490 
491 	tcon->dclk_min_div = 6;
492 	tcon->dclk_max_div = 127;
493 	sun4i_tcon0_mode_set_common(tcon, mode);
494 
495 	/* Set dithering if needed */
496 	sun4i_tcon0_mode_set_dithering(tcon, connector);
497 
498 	/* Adjust clock delay */
499 	clk_delay = sun4i_tcon_get_clk_delay(mode, 0);
500 	regmap_update_bits(tcon->regs, SUN4I_TCON0_CTL_REG,
501 			   SUN4I_TCON0_CTL_CLK_DELAY_MASK,
502 			   SUN4I_TCON0_CTL_CLK_DELAY(clk_delay));
503 
504 	/*
505 	 * This is called a backporch in the register documentation,
506 	 * but it really is the back porch + hsync
507 	 */
508 	bp = mode->crtc_htotal - mode->crtc_hsync_start;
509 	DRM_DEBUG_DRIVER("Setting horizontal total %d, backporch %d\n",
510 			 mode->crtc_htotal, bp);
511 
512 	/* Set horizontal display timings */
513 	regmap_write(tcon->regs, SUN4I_TCON0_BASIC1_REG,
514 		     SUN4I_TCON0_BASIC1_H_TOTAL(mode->crtc_htotal) |
515 		     SUN4I_TCON0_BASIC1_H_BACKPORCH(bp));
516 
517 	/*
518 	 * This is called a backporch in the register documentation,
519 	 * but it really is the back porch + hsync
520 	 */
521 	bp = mode->crtc_vtotal - mode->crtc_vsync_start;
522 	DRM_DEBUG_DRIVER("Setting vertical total %d, backporch %d\n",
523 			 mode->crtc_vtotal, bp);
524 
525 	/* Set vertical display timings */
526 	regmap_write(tcon->regs, SUN4I_TCON0_BASIC2_REG,
527 		     SUN4I_TCON0_BASIC2_V_TOTAL(mode->crtc_vtotal * 2) |
528 		     SUN4I_TCON0_BASIC2_V_BACKPORCH(bp));
529 
530 	/* Set Hsync and Vsync length */
531 	hsync = mode->crtc_hsync_end - mode->crtc_hsync_start;
532 	vsync = mode->crtc_vsync_end - mode->crtc_vsync_start;
533 	DRM_DEBUG_DRIVER("Setting HSYNC %d, VSYNC %d\n", hsync, vsync);
534 	regmap_write(tcon->regs, SUN4I_TCON0_BASIC3_REG,
535 		     SUN4I_TCON0_BASIC3_V_SYNC(vsync) |
536 		     SUN4I_TCON0_BASIC3_H_SYNC(hsync));
537 
538 	/* Setup the polarity of the various signals */
539 	if (mode->flags & DRM_MODE_FLAG_PHSYNC)
540 		val |= SUN4I_TCON0_IO_POL_HSYNC_POSITIVE;
541 
542 	if (mode->flags & DRM_MODE_FLAG_PVSYNC)
543 		val |= SUN4I_TCON0_IO_POL_VSYNC_POSITIVE;
544 
545 	if (info->bus_flags & DRM_BUS_FLAG_DE_LOW)
546 		val |= SUN4I_TCON0_IO_POL_DE_NEGATIVE;
547 
548 	/*
549 	 * On A20 and similar SoCs, the only way to achieve Positive Edge
550 	 * (Rising Edge), is setting dclk clock phase to 2/3(240°).
551 	 * By default TCON works in Negative Edge(Falling Edge),
552 	 * this is why phase is set to 0 in that case.
553 	 * Unfortunately there's no way to logically invert dclk through
554 	 * IO_POL register.
555 	 * The only acceptable way to work, triple checked with scope,
556 	 * is using clock phase set to 0° for Negative Edge and set to 240°
557 	 * for Positive Edge.
558 	 * On A33 and similar SoCs there would be a 90° phase option,
559 	 * but it divides also dclk by 2.
560 	 * Following code is a way to avoid quirks all around TCON
561 	 * and DOTCLOCK drivers.
562 	 */
563 	if (info->bus_flags & DRM_BUS_FLAG_PIXDATA_DRIVE_POSEDGE)
564 		clk_set_phase(tcon->dclk, 240);
565 
566 	if (info->bus_flags & DRM_BUS_FLAG_PIXDATA_DRIVE_NEGEDGE)
567 		clk_set_phase(tcon->dclk, 0);
568 
569 	regmap_update_bits(tcon->regs, SUN4I_TCON0_IO_POL_REG,
570 			   SUN4I_TCON0_IO_POL_HSYNC_POSITIVE |
571 			   SUN4I_TCON0_IO_POL_VSYNC_POSITIVE |
572 			   SUN4I_TCON0_IO_POL_DE_NEGATIVE,
573 			   val);
574 
575 	/* Map output pins to channel 0 */
576 	regmap_update_bits(tcon->regs, SUN4I_TCON_GCTL_REG,
577 			   SUN4I_TCON_GCTL_IOMAP_MASK,
578 			   SUN4I_TCON_GCTL_IOMAP_TCON0);
579 
580 	/* Enable the output on the pins */
581 	regmap_write(tcon->regs, SUN4I_TCON0_IO_TRI_REG, 0);
582 }
583 
584 static void sun4i_tcon1_mode_set(struct sun4i_tcon *tcon,
585 				 const struct drm_display_mode *mode)
586 {
587 	unsigned int bp, hsync, vsync, vtotal;
588 	u8 clk_delay;
589 	u32 val;
590 
591 	WARN_ON(!tcon->quirks->has_channel_1);
592 
593 	/* Configure the dot clock */
594 	clk_set_rate(tcon->sclk1, mode->crtc_clock * 1000);
595 
596 	/* Adjust clock delay */
597 	clk_delay = sun4i_tcon_get_clk_delay(mode, 1);
598 	regmap_update_bits(tcon->regs, SUN4I_TCON1_CTL_REG,
599 			   SUN4I_TCON1_CTL_CLK_DELAY_MASK,
600 			   SUN4I_TCON1_CTL_CLK_DELAY(clk_delay));
601 
602 	/* Set interlaced mode */
603 	if (mode->flags & DRM_MODE_FLAG_INTERLACE)
604 		val = SUN4I_TCON1_CTL_INTERLACE_ENABLE;
605 	else
606 		val = 0;
607 	regmap_update_bits(tcon->regs, SUN4I_TCON1_CTL_REG,
608 			   SUN4I_TCON1_CTL_INTERLACE_ENABLE,
609 			   val);
610 
611 	/* Set the input resolution */
612 	regmap_write(tcon->regs, SUN4I_TCON1_BASIC0_REG,
613 		     SUN4I_TCON1_BASIC0_X(mode->crtc_hdisplay) |
614 		     SUN4I_TCON1_BASIC0_Y(mode->crtc_vdisplay));
615 
616 	/* Set the upscaling resolution */
617 	regmap_write(tcon->regs, SUN4I_TCON1_BASIC1_REG,
618 		     SUN4I_TCON1_BASIC1_X(mode->crtc_hdisplay) |
619 		     SUN4I_TCON1_BASIC1_Y(mode->crtc_vdisplay));
620 
621 	/* Set the output resolution */
622 	regmap_write(tcon->regs, SUN4I_TCON1_BASIC2_REG,
623 		     SUN4I_TCON1_BASIC2_X(mode->crtc_hdisplay) |
624 		     SUN4I_TCON1_BASIC2_Y(mode->crtc_vdisplay));
625 
626 	/* Set horizontal display timings */
627 	bp = mode->crtc_htotal - mode->crtc_hsync_start;
628 	DRM_DEBUG_DRIVER("Setting horizontal total %d, backporch %d\n",
629 			 mode->htotal, bp);
630 	regmap_write(tcon->regs, SUN4I_TCON1_BASIC3_REG,
631 		     SUN4I_TCON1_BASIC3_H_TOTAL(mode->crtc_htotal) |
632 		     SUN4I_TCON1_BASIC3_H_BACKPORCH(bp));
633 
634 	bp = mode->crtc_vtotal - mode->crtc_vsync_start;
635 	DRM_DEBUG_DRIVER("Setting vertical total %d, backporch %d\n",
636 			 mode->crtc_vtotal, bp);
637 
638 	/*
639 	 * The vertical resolution needs to be doubled in all
640 	 * cases. We could use crtc_vtotal and always multiply by two,
641 	 * but that leads to a rounding error in interlace when vtotal
642 	 * is odd.
643 	 *
644 	 * This happens with TV's PAL for example, where vtotal will
645 	 * be 625, crtc_vtotal 312, and thus crtc_vtotal * 2 will be
646 	 * 624, which apparently confuses the hardware.
647 	 *
648 	 * To work around this, we will always use vtotal, and
649 	 * multiply by two only if we're not in interlace.
650 	 */
651 	vtotal = mode->vtotal;
652 	if (!(mode->flags & DRM_MODE_FLAG_INTERLACE))
653 		vtotal = vtotal * 2;
654 
655 	/* Set vertical display timings */
656 	regmap_write(tcon->regs, SUN4I_TCON1_BASIC4_REG,
657 		     SUN4I_TCON1_BASIC4_V_TOTAL(vtotal) |
658 		     SUN4I_TCON1_BASIC4_V_BACKPORCH(bp));
659 
660 	/* Set Hsync and Vsync length */
661 	hsync = mode->crtc_hsync_end - mode->crtc_hsync_start;
662 	vsync = mode->crtc_vsync_end - mode->crtc_vsync_start;
663 	DRM_DEBUG_DRIVER("Setting HSYNC %d, VSYNC %d\n", hsync, vsync);
664 	regmap_write(tcon->regs, SUN4I_TCON1_BASIC5_REG,
665 		     SUN4I_TCON1_BASIC5_V_SYNC(vsync) |
666 		     SUN4I_TCON1_BASIC5_H_SYNC(hsync));
667 
668 	/* Map output pins to channel 1 */
669 	regmap_update_bits(tcon->regs, SUN4I_TCON_GCTL_REG,
670 			   SUN4I_TCON_GCTL_IOMAP_MASK,
671 			   SUN4I_TCON_GCTL_IOMAP_TCON1);
672 }
673 
674 void sun4i_tcon_mode_set(struct sun4i_tcon *tcon,
675 			 const struct drm_encoder *encoder,
676 			 const struct drm_display_mode *mode)
677 {
678 	switch (encoder->encoder_type) {
679 	case DRM_MODE_ENCODER_DSI:
680 		/* DSI is tied to special case of CPU interface */
681 		sun4i_tcon0_mode_set_cpu(tcon, encoder, mode);
682 		break;
683 	case DRM_MODE_ENCODER_LVDS:
684 		sun4i_tcon0_mode_set_lvds(tcon, encoder, mode);
685 		break;
686 	case DRM_MODE_ENCODER_NONE:
687 		sun4i_tcon0_mode_set_rgb(tcon, encoder, mode);
688 		sun4i_tcon_set_mux(tcon, 0, encoder);
689 		break;
690 	case DRM_MODE_ENCODER_TVDAC:
691 	case DRM_MODE_ENCODER_TMDS:
692 		sun4i_tcon1_mode_set(tcon, mode);
693 		sun4i_tcon_set_mux(tcon, 1, encoder);
694 		break;
695 	default:
696 		DRM_DEBUG_DRIVER("Unknown encoder type, doing nothing...\n");
697 	}
698 }
699 EXPORT_SYMBOL(sun4i_tcon_mode_set);
700 
701 static void sun4i_tcon_finish_page_flip(struct drm_device *dev,
702 					struct sun4i_crtc *scrtc)
703 {
704 	unsigned long flags;
705 
706 	spin_lock_irqsave(&dev->event_lock, flags);
707 	if (scrtc->event) {
708 		drm_crtc_send_vblank_event(&scrtc->crtc, scrtc->event);
709 		drm_crtc_vblank_put(&scrtc->crtc);
710 		scrtc->event = NULL;
711 	}
712 	spin_unlock_irqrestore(&dev->event_lock, flags);
713 }
714 
715 static irqreturn_t sun4i_tcon_handler(int irq, void *private)
716 {
717 	struct sun4i_tcon *tcon = private;
718 	struct drm_device *drm = tcon->drm;
719 	struct sun4i_crtc *scrtc = tcon->crtc;
720 	struct sunxi_engine *engine = scrtc->engine;
721 	unsigned int status;
722 
723 	regmap_read(tcon->regs, SUN4I_TCON_GINT0_REG, &status);
724 
725 	if (!(status & (SUN4I_TCON_GINT0_VBLANK_INT(0) |
726 			SUN4I_TCON_GINT0_VBLANK_INT(1) |
727 			SUN4I_TCON_GINT0_TCON0_TRI_FINISH_INT)))
728 		return IRQ_NONE;
729 
730 	drm_crtc_handle_vblank(&scrtc->crtc);
731 	sun4i_tcon_finish_page_flip(drm, scrtc);
732 
733 	/* Acknowledge the interrupt */
734 	regmap_update_bits(tcon->regs, SUN4I_TCON_GINT0_REG,
735 			   SUN4I_TCON_GINT0_VBLANK_INT(0) |
736 			   SUN4I_TCON_GINT0_VBLANK_INT(1) |
737 			   SUN4I_TCON_GINT0_TCON0_TRI_FINISH_INT,
738 			   0);
739 
740 	if (engine->ops->vblank_quirk)
741 		engine->ops->vblank_quirk(engine);
742 
743 	return IRQ_HANDLED;
744 }
745 
746 static int sun4i_tcon_init_clocks(struct device *dev,
747 				  struct sun4i_tcon *tcon)
748 {
749 	tcon->clk = devm_clk_get(dev, "ahb");
750 	if (IS_ERR(tcon->clk)) {
751 		dev_err(dev, "Couldn't get the TCON bus clock\n");
752 		return PTR_ERR(tcon->clk);
753 	}
754 	clk_prepare_enable(tcon->clk);
755 
756 	if (tcon->quirks->has_channel_0) {
757 		tcon->sclk0 = devm_clk_get(dev, "tcon-ch0");
758 		if (IS_ERR(tcon->sclk0)) {
759 			dev_err(dev, "Couldn't get the TCON channel 0 clock\n");
760 			return PTR_ERR(tcon->sclk0);
761 		}
762 	}
763 	clk_prepare_enable(tcon->sclk0);
764 
765 	if (tcon->quirks->has_channel_1) {
766 		tcon->sclk1 = devm_clk_get(dev, "tcon-ch1");
767 		if (IS_ERR(tcon->sclk1)) {
768 			dev_err(dev, "Couldn't get the TCON channel 1 clock\n");
769 			return PTR_ERR(tcon->sclk1);
770 		}
771 	}
772 
773 	return 0;
774 }
775 
776 static void sun4i_tcon_free_clocks(struct sun4i_tcon *tcon)
777 {
778 	clk_disable_unprepare(tcon->sclk0);
779 	clk_disable_unprepare(tcon->clk);
780 }
781 
782 static int sun4i_tcon_init_irq(struct device *dev,
783 			       struct sun4i_tcon *tcon)
784 {
785 	struct platform_device *pdev = to_platform_device(dev);
786 	int irq, ret;
787 
788 	irq = platform_get_irq(pdev, 0);
789 	if (irq < 0) {
790 		dev_err(dev, "Couldn't retrieve the TCON interrupt\n");
791 		return irq;
792 	}
793 
794 	ret = devm_request_irq(dev, irq, sun4i_tcon_handler, 0,
795 			       dev_name(dev), tcon);
796 	if (ret) {
797 		dev_err(dev, "Couldn't request the IRQ\n");
798 		return ret;
799 	}
800 
801 	return 0;
802 }
803 
804 static struct regmap_config sun4i_tcon_regmap_config = {
805 	.reg_bits	= 32,
806 	.val_bits	= 32,
807 	.reg_stride	= 4,
808 	.max_register	= 0x800,
809 };
810 
811 static int sun4i_tcon_init_regmap(struct device *dev,
812 				  struct sun4i_tcon *tcon)
813 {
814 	struct platform_device *pdev = to_platform_device(dev);
815 	struct resource *res;
816 	void __iomem *regs;
817 
818 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
819 	regs = devm_ioremap_resource(dev, res);
820 	if (IS_ERR(regs))
821 		return PTR_ERR(regs);
822 
823 	tcon->regs = devm_regmap_init_mmio(dev, regs,
824 					   &sun4i_tcon_regmap_config);
825 	if (IS_ERR(tcon->regs)) {
826 		dev_err(dev, "Couldn't create the TCON regmap\n");
827 		return PTR_ERR(tcon->regs);
828 	}
829 
830 	/* Make sure the TCON is disabled and all IRQs are off */
831 	regmap_write(tcon->regs, SUN4I_TCON_GCTL_REG, 0);
832 	regmap_write(tcon->regs, SUN4I_TCON_GINT0_REG, 0);
833 	regmap_write(tcon->regs, SUN4I_TCON_GINT1_REG, 0);
834 
835 	/* Disable IO lines and set them to tristate */
836 	regmap_write(tcon->regs, SUN4I_TCON0_IO_TRI_REG, ~0);
837 	regmap_write(tcon->regs, SUN4I_TCON1_IO_TRI_REG, ~0);
838 
839 	return 0;
840 }
841 
842 /*
843  * On SoCs with the old display pipeline design (Display Engine 1.0),
844  * the TCON is always tied to just one backend. Hence we can traverse
845  * the of_graph upwards to find the backend our tcon is connected to,
846  * and take its ID as our own.
847  *
848  * We can either identify backends from their compatible strings, which
849  * means maintaining a large list of them. Or, since the backend is
850  * registered and binded before the TCON, we can just go through the
851  * list of registered backends and compare the device node.
852  *
853  * As the structures now store engines instead of backends, here this
854  * function in fact searches the corresponding engine, and the ID is
855  * requested via the get_id function of the engine.
856  */
857 static struct sunxi_engine *
858 sun4i_tcon_find_engine_traverse(struct sun4i_drv *drv,
859 				struct device_node *node,
860 				u32 port_id)
861 {
862 	struct device_node *port, *ep, *remote;
863 	struct sunxi_engine *engine = ERR_PTR(-EINVAL);
864 	u32 reg = 0;
865 
866 	port = of_graph_get_port_by_id(node, port_id);
867 	if (!port)
868 		return ERR_PTR(-EINVAL);
869 
870 	/*
871 	 * This only works if there is only one path from the TCON
872 	 * to any display engine. Otherwise the probe order of the
873 	 * TCONs and display engines is not guaranteed. They may
874 	 * either bind to the wrong one, or worse, bind to the same
875 	 * one if additional checks are not done.
876 	 *
877 	 * Bail out if there are multiple input connections.
878 	 */
879 	if (of_get_available_child_count(port) != 1)
880 		goto out_put_port;
881 
882 	/* Get the first connection without specifying an ID */
883 	ep = of_get_next_available_child(port, NULL);
884 	if (!ep)
885 		goto out_put_port;
886 
887 	remote = of_graph_get_remote_port_parent(ep);
888 	if (!remote)
889 		goto out_put_ep;
890 
891 	/* does this node match any registered engines? */
892 	list_for_each_entry(engine, &drv->engine_list, list)
893 		if (remote == engine->node)
894 			goto out_put_remote;
895 
896 	/*
897 	 * According to device tree binding input ports have even id
898 	 * number and output ports have odd id. Since component with
899 	 * more than one input and one output (TCON TOP) exits, correct
900 	 * remote input id has to be calculated by subtracting 1 from
901 	 * remote output id. If this for some reason can't be done, 0
902 	 * is used as input port id.
903 	 */
904 	of_node_put(port);
905 	port = of_graph_get_remote_port(ep);
906 	if (!of_property_read_u32(port, "reg", &reg) && reg > 0)
907 		reg -= 1;
908 
909 	/* keep looking through upstream ports */
910 	engine = sun4i_tcon_find_engine_traverse(drv, remote, reg);
911 
912 out_put_remote:
913 	of_node_put(remote);
914 out_put_ep:
915 	of_node_put(ep);
916 out_put_port:
917 	of_node_put(port);
918 
919 	return engine;
920 }
921 
922 /*
923  * The device tree binding says that the remote endpoint ID of any
924  * connection between components, up to and including the TCON, of
925  * the display pipeline should be equal to the actual ID of the local
926  * component. Thus we can look at any one of the input connections of
927  * the TCONs, and use that connection's remote endpoint ID as our own.
928  *
929  * Since the user of this function already finds the input port,
930  * the port is passed in directly without further checks.
931  */
932 static int sun4i_tcon_of_get_id_from_port(struct device_node *port)
933 {
934 	struct device_node *ep;
935 	int ret = -EINVAL;
936 
937 	/* try finding an upstream endpoint */
938 	for_each_available_child_of_node(port, ep) {
939 		struct device_node *remote;
940 		u32 reg;
941 
942 		remote = of_graph_get_remote_endpoint(ep);
943 		if (!remote)
944 			continue;
945 
946 		ret = of_property_read_u32(remote, "reg", &reg);
947 		if (ret)
948 			continue;
949 
950 		ret = reg;
951 	}
952 
953 	return ret;
954 }
955 
956 /*
957  * Once we know the TCON's id, we can look through the list of
958  * engines to find a matching one. We assume all engines have
959  * been probed and added to the list.
960  */
961 static struct sunxi_engine *sun4i_tcon_get_engine_by_id(struct sun4i_drv *drv,
962 							int id)
963 {
964 	struct sunxi_engine *engine;
965 
966 	list_for_each_entry(engine, &drv->engine_list, list)
967 		if (engine->id == id)
968 			return engine;
969 
970 	return ERR_PTR(-EINVAL);
971 }
972 
973 static bool sun4i_tcon_connected_to_tcon_top(struct device_node *node)
974 {
975 	struct device_node *remote;
976 	bool ret = false;
977 
978 	remote = of_graph_get_remote_node(node, 0, -1);
979 	if (remote) {
980 		ret = !!(IS_ENABLED(CONFIG_DRM_SUN8I_TCON_TOP) &&
981 			 of_match_node(sun8i_tcon_top_of_table, remote));
982 		of_node_put(remote);
983 	}
984 
985 	return ret;
986 }
987 
988 static int sun4i_tcon_get_index(struct sun4i_drv *drv)
989 {
990 	struct list_head *pos;
991 	int size = 0;
992 
993 	/*
994 	 * Because TCON is added to the list at the end of the probe
995 	 * (after this function is called), index of the current TCON
996 	 * will be same as current TCON list size.
997 	 */
998 	list_for_each(pos, &drv->tcon_list)
999 		++size;
1000 
1001 	return size;
1002 }
1003 
1004 /*
1005  * On SoCs with the old display pipeline design (Display Engine 1.0),
1006  * we assumed the TCON was always tied to just one backend. However
1007  * this proved not to be the case. On the A31, the TCON can select
1008  * either backend as its source. On the A20 (and likely on the A10),
1009  * the backend can choose which TCON to output to.
1010  *
1011  * The device tree binding says that the remote endpoint ID of any
1012  * connection between components, up to and including the TCON, of
1013  * the display pipeline should be equal to the actual ID of the local
1014  * component. Thus we should be able to look at any one of the input
1015  * connections of the TCONs, and use that connection's remote endpoint
1016  * ID as our own.
1017  *
1018  * However  the connections between the backend and TCON were assumed
1019  * to be always singular, and their endpoit IDs were all incorrectly
1020  * set to 0. This means for these old device trees, we cannot just look
1021  * up the remote endpoint ID of a TCON input endpoint. TCON1 would be
1022  * incorrectly identified as TCON0.
1023  *
1024  * This function first checks if the TCON node has 2 input endpoints.
1025  * If so, then the device tree is a corrected version, and it will use
1026  * sun4i_tcon_of_get_id() and sun4i_tcon_get_engine_by_id() from above
1027  * to fetch the ID and engine directly. If not, then it is likely an
1028  * old device trees, where the endpoint IDs were incorrect, but did not
1029  * have endpoint connections between the backend and TCON across
1030  * different display pipelines. It will fall back to the old method of
1031  * traversing the  of_graph to try and find a matching engine by device
1032  * node.
1033  *
1034  * In the case of single display pipeline device trees, either method
1035  * works.
1036  */
1037 static struct sunxi_engine *sun4i_tcon_find_engine(struct sun4i_drv *drv,
1038 						   struct device_node *node)
1039 {
1040 	struct device_node *port;
1041 	struct sunxi_engine *engine;
1042 
1043 	port = of_graph_get_port_by_id(node, 0);
1044 	if (!port)
1045 		return ERR_PTR(-EINVAL);
1046 
1047 	/*
1048 	 * Is this a corrected device tree with cross pipeline
1049 	 * connections between the backend and TCON?
1050 	 */
1051 	if (of_get_child_count(port) > 1) {
1052 		int id;
1053 
1054 		/*
1055 		 * When pipeline has the same number of TCONs and engines which
1056 		 * are represented by frontends/backends (DE1) or mixers (DE2),
1057 		 * we match them by their respective IDs. However, if pipeline
1058 		 * contains TCON TOP, chances are that there are either more
1059 		 * TCONs than engines (R40) or TCONs with non-consecutive ids.
1060 		 * (H6). In that case it's easier just use TCON index in list
1061 		 * as an id. That means that on R40, any 2 TCONs can be enabled
1062 		 * in DT out of 4 (there are 2 mixers). Due to the design of
1063 		 * TCON TOP, remaining 2 TCONs can't be connected to anything
1064 		 * anyway.
1065 		 */
1066 		if (sun4i_tcon_connected_to_tcon_top(node))
1067 			id = sun4i_tcon_get_index(drv);
1068 		else
1069 			id = sun4i_tcon_of_get_id_from_port(port);
1070 
1071 		/* Get our engine by matching our ID */
1072 		engine = sun4i_tcon_get_engine_by_id(drv, id);
1073 
1074 		of_node_put(port);
1075 		return engine;
1076 	}
1077 
1078 	/* Fallback to old method by traversing input endpoints */
1079 	of_node_put(port);
1080 	return sun4i_tcon_find_engine_traverse(drv, node, 0);
1081 }
1082 
1083 static int sun4i_tcon_bind(struct device *dev, struct device *master,
1084 			   void *data)
1085 {
1086 	struct drm_device *drm = data;
1087 	struct sun4i_drv *drv = drm->dev_private;
1088 	struct sunxi_engine *engine;
1089 	struct device_node *remote;
1090 	struct sun4i_tcon *tcon;
1091 	struct reset_control *edp_rstc;
1092 	bool has_lvds_rst, has_lvds_alt, can_lvds;
1093 	int ret;
1094 
1095 	engine = sun4i_tcon_find_engine(drv, dev->of_node);
1096 	if (IS_ERR(engine)) {
1097 		dev_err(dev, "Couldn't find matching engine\n");
1098 		return -EPROBE_DEFER;
1099 	}
1100 
1101 	tcon = devm_kzalloc(dev, sizeof(*tcon), GFP_KERNEL);
1102 	if (!tcon)
1103 		return -ENOMEM;
1104 	dev_set_drvdata(dev, tcon);
1105 	tcon->drm = drm;
1106 	tcon->dev = dev;
1107 	tcon->id = engine->id;
1108 	tcon->quirks = of_device_get_match_data(dev);
1109 
1110 	tcon->lcd_rst = devm_reset_control_get(dev, "lcd");
1111 	if (IS_ERR(tcon->lcd_rst)) {
1112 		dev_err(dev, "Couldn't get our reset line\n");
1113 		return PTR_ERR(tcon->lcd_rst);
1114 	}
1115 
1116 	if (tcon->quirks->needs_edp_reset) {
1117 		edp_rstc = devm_reset_control_get_shared(dev, "edp");
1118 		if (IS_ERR(edp_rstc)) {
1119 			dev_err(dev, "Couldn't get edp reset line\n");
1120 			return PTR_ERR(edp_rstc);
1121 		}
1122 
1123 		ret = reset_control_deassert(edp_rstc);
1124 		if (ret) {
1125 			dev_err(dev, "Couldn't deassert edp reset line\n");
1126 			return ret;
1127 		}
1128 	}
1129 
1130 	/* Make sure our TCON is reset */
1131 	ret = reset_control_reset(tcon->lcd_rst);
1132 	if (ret) {
1133 		dev_err(dev, "Couldn't deassert our reset line\n");
1134 		return ret;
1135 	}
1136 
1137 	if (tcon->quirks->supports_lvds) {
1138 		/*
1139 		 * This can only be made optional since we've had DT
1140 		 * nodes without the LVDS reset properties.
1141 		 *
1142 		 * If the property is missing, just disable LVDS, and
1143 		 * print a warning.
1144 		 */
1145 		tcon->lvds_rst = devm_reset_control_get_optional(dev, "lvds");
1146 		if (IS_ERR(tcon->lvds_rst)) {
1147 			dev_err(dev, "Couldn't get our reset line\n");
1148 			return PTR_ERR(tcon->lvds_rst);
1149 		} else if (tcon->lvds_rst) {
1150 			has_lvds_rst = true;
1151 			reset_control_reset(tcon->lvds_rst);
1152 		} else {
1153 			has_lvds_rst = false;
1154 		}
1155 
1156 		/*
1157 		 * This can only be made optional since we've had DT
1158 		 * nodes without the LVDS reset properties.
1159 		 *
1160 		 * If the property is missing, just disable LVDS, and
1161 		 * print a warning.
1162 		 */
1163 		if (tcon->quirks->has_lvds_alt) {
1164 			tcon->lvds_pll = devm_clk_get(dev, "lvds-alt");
1165 			if (IS_ERR(tcon->lvds_pll)) {
1166 				if (PTR_ERR(tcon->lvds_pll) == -ENOENT) {
1167 					has_lvds_alt = false;
1168 				} else {
1169 					dev_err(dev, "Couldn't get the LVDS PLL\n");
1170 					return PTR_ERR(tcon->lvds_pll);
1171 				}
1172 			} else {
1173 				has_lvds_alt = true;
1174 			}
1175 		}
1176 
1177 		if (!has_lvds_rst ||
1178 		    (tcon->quirks->has_lvds_alt && !has_lvds_alt)) {
1179 			dev_warn(dev, "Missing LVDS properties, Please upgrade your DT\n");
1180 			dev_warn(dev, "LVDS output disabled\n");
1181 			can_lvds = false;
1182 		} else {
1183 			can_lvds = true;
1184 		}
1185 	} else {
1186 		can_lvds = false;
1187 	}
1188 
1189 	ret = sun4i_tcon_init_clocks(dev, tcon);
1190 	if (ret) {
1191 		dev_err(dev, "Couldn't init our TCON clocks\n");
1192 		goto err_assert_reset;
1193 	}
1194 
1195 	ret = sun4i_tcon_init_regmap(dev, tcon);
1196 	if (ret) {
1197 		dev_err(dev, "Couldn't init our TCON regmap\n");
1198 		goto err_free_clocks;
1199 	}
1200 
1201 	if (tcon->quirks->has_channel_0) {
1202 		ret = sun4i_dclk_create(dev, tcon);
1203 		if (ret) {
1204 			dev_err(dev, "Couldn't create our TCON dot clock\n");
1205 			goto err_free_clocks;
1206 		}
1207 	}
1208 
1209 	ret = sun4i_tcon_init_irq(dev, tcon);
1210 	if (ret) {
1211 		dev_err(dev, "Couldn't init our TCON interrupts\n");
1212 		goto err_free_dotclock;
1213 	}
1214 
1215 	tcon->crtc = sun4i_crtc_init(drm, engine, tcon);
1216 	if (IS_ERR(tcon->crtc)) {
1217 		dev_err(dev, "Couldn't create our CRTC\n");
1218 		ret = PTR_ERR(tcon->crtc);
1219 		goto err_free_dotclock;
1220 	}
1221 
1222 	if (tcon->quirks->has_channel_0) {
1223 		/*
1224 		 * If we have an LVDS panel connected to the TCON, we should
1225 		 * just probe the LVDS connector. Otherwise, just probe RGB as
1226 		 * we used to.
1227 		 */
1228 		remote = of_graph_get_remote_node(dev->of_node, 1, 0);
1229 		if (of_device_is_compatible(remote, "panel-lvds"))
1230 			if (can_lvds)
1231 				ret = sun4i_lvds_init(drm, tcon);
1232 			else
1233 				ret = -EINVAL;
1234 		else
1235 			ret = sun4i_rgb_init(drm, tcon);
1236 		of_node_put(remote);
1237 
1238 		if (ret < 0)
1239 			goto err_free_dotclock;
1240 	}
1241 
1242 	if (tcon->quirks->needs_de_be_mux) {
1243 		/*
1244 		 * We assume there is no dynamic muxing of backends
1245 		 * and TCONs, so we select the backend with same ID.
1246 		 *
1247 		 * While dynamic selection might be interesting, since
1248 		 * the CRTC is tied to the TCON, while the layers are
1249 		 * tied to the backends, this means, we will need to
1250 		 * switch between groups of layers. There might not be
1251 		 * a way to represent this constraint in DRM.
1252 		 */
1253 		regmap_update_bits(tcon->regs, SUN4I_TCON0_CTL_REG,
1254 				   SUN4I_TCON0_CTL_SRC_SEL_MASK,
1255 				   tcon->id);
1256 		regmap_update_bits(tcon->regs, SUN4I_TCON1_CTL_REG,
1257 				   SUN4I_TCON1_CTL_SRC_SEL_MASK,
1258 				   tcon->id);
1259 	}
1260 
1261 	list_add_tail(&tcon->list, &drv->tcon_list);
1262 
1263 	return 0;
1264 
1265 err_free_dotclock:
1266 	if (tcon->quirks->has_channel_0)
1267 		sun4i_dclk_free(tcon);
1268 err_free_clocks:
1269 	sun4i_tcon_free_clocks(tcon);
1270 err_assert_reset:
1271 	reset_control_assert(tcon->lcd_rst);
1272 	return ret;
1273 }
1274 
1275 static void sun4i_tcon_unbind(struct device *dev, struct device *master,
1276 			      void *data)
1277 {
1278 	struct sun4i_tcon *tcon = dev_get_drvdata(dev);
1279 
1280 	list_del(&tcon->list);
1281 	if (tcon->quirks->has_channel_0)
1282 		sun4i_dclk_free(tcon);
1283 	sun4i_tcon_free_clocks(tcon);
1284 }
1285 
1286 static const struct component_ops sun4i_tcon_ops = {
1287 	.bind	= sun4i_tcon_bind,
1288 	.unbind	= sun4i_tcon_unbind,
1289 };
1290 
1291 static int sun4i_tcon_probe(struct platform_device *pdev)
1292 {
1293 	struct device_node *node = pdev->dev.of_node;
1294 	const struct sun4i_tcon_quirks *quirks;
1295 	struct drm_bridge *bridge;
1296 	struct drm_panel *panel;
1297 	int ret;
1298 
1299 	quirks = of_device_get_match_data(&pdev->dev);
1300 
1301 	/* panels and bridges are present only on TCONs with channel 0 */
1302 	if (quirks->has_channel_0) {
1303 		ret = drm_of_find_panel_or_bridge(node, 1, 0, &panel, &bridge);
1304 		if (ret == -EPROBE_DEFER)
1305 			return ret;
1306 	}
1307 
1308 	return component_add(&pdev->dev, &sun4i_tcon_ops);
1309 }
1310 
1311 static int sun4i_tcon_remove(struct platform_device *pdev)
1312 {
1313 	component_del(&pdev->dev, &sun4i_tcon_ops);
1314 
1315 	return 0;
1316 }
1317 
1318 /* platform specific TCON muxing callbacks */
1319 static int sun4i_a10_tcon_set_mux(struct sun4i_tcon *tcon,
1320 				  const struct drm_encoder *encoder)
1321 {
1322 	struct sun4i_tcon *tcon0 = sun4i_get_tcon0(encoder->dev);
1323 	u32 shift;
1324 
1325 	if (!tcon0)
1326 		return -EINVAL;
1327 
1328 	switch (encoder->encoder_type) {
1329 	case DRM_MODE_ENCODER_TMDS:
1330 		/* HDMI */
1331 		shift = 8;
1332 		break;
1333 	default:
1334 		return -EINVAL;
1335 	}
1336 
1337 	regmap_update_bits(tcon0->regs, SUN4I_TCON_MUX_CTRL_REG,
1338 			   0x3 << shift, tcon->id << shift);
1339 
1340 	return 0;
1341 }
1342 
1343 static int sun5i_a13_tcon_set_mux(struct sun4i_tcon *tcon,
1344 				  const struct drm_encoder *encoder)
1345 {
1346 	u32 val;
1347 
1348 	if (encoder->encoder_type == DRM_MODE_ENCODER_TVDAC)
1349 		val = 1;
1350 	else
1351 		val = 0;
1352 
1353 	/*
1354 	 * FIXME: Undocumented bits
1355 	 */
1356 	return regmap_write(tcon->regs, SUN4I_TCON_MUX_CTRL_REG, val);
1357 }
1358 
1359 static int sun6i_tcon_set_mux(struct sun4i_tcon *tcon,
1360 			      const struct drm_encoder *encoder)
1361 {
1362 	struct sun4i_tcon *tcon0 = sun4i_get_tcon0(encoder->dev);
1363 	u32 shift;
1364 
1365 	if (!tcon0)
1366 		return -EINVAL;
1367 
1368 	switch (encoder->encoder_type) {
1369 	case DRM_MODE_ENCODER_TMDS:
1370 		/* HDMI */
1371 		shift = 8;
1372 		break;
1373 	default:
1374 		/* TODO A31 has MIPI DSI but A31s does not */
1375 		return -EINVAL;
1376 	}
1377 
1378 	regmap_update_bits(tcon0->regs, SUN4I_TCON_MUX_CTRL_REG,
1379 			   0x3 << shift, tcon->id << shift);
1380 
1381 	return 0;
1382 }
1383 
1384 static int sun8i_r40_tcon_tv_set_mux(struct sun4i_tcon *tcon,
1385 				     const struct drm_encoder *encoder)
1386 {
1387 	struct device_node *port, *remote;
1388 	struct platform_device *pdev;
1389 	int id, ret;
1390 
1391 	/* find TCON TOP platform device and TCON id */
1392 
1393 	port = of_graph_get_port_by_id(tcon->dev->of_node, 0);
1394 	if (!port)
1395 		return -EINVAL;
1396 
1397 	id = sun4i_tcon_of_get_id_from_port(port);
1398 	of_node_put(port);
1399 
1400 	remote = of_graph_get_remote_node(tcon->dev->of_node, 0, -1);
1401 	if (!remote)
1402 		return -EINVAL;
1403 
1404 	pdev = of_find_device_by_node(remote);
1405 	of_node_put(remote);
1406 	if (!pdev)
1407 		return -EINVAL;
1408 
1409 	if (IS_ENABLED(CONFIG_DRM_SUN8I_TCON_TOP) &&
1410 	    encoder->encoder_type == DRM_MODE_ENCODER_TMDS) {
1411 		ret = sun8i_tcon_top_set_hdmi_src(&pdev->dev, id);
1412 		if (ret)
1413 			return ret;
1414 	}
1415 
1416 	if (IS_ENABLED(CONFIG_DRM_SUN8I_TCON_TOP)) {
1417 		ret = sun8i_tcon_top_de_config(&pdev->dev, tcon->id, id);
1418 		if (ret)
1419 			return ret;
1420 	}
1421 
1422 	return 0;
1423 }
1424 
1425 static const struct sun4i_tcon_quirks sun4i_a10_quirks = {
1426 	.has_channel_0		= true,
1427 	.has_channel_1		= true,
1428 	.set_mux		= sun4i_a10_tcon_set_mux,
1429 };
1430 
1431 static const struct sun4i_tcon_quirks sun5i_a13_quirks = {
1432 	.has_channel_0		= true,
1433 	.has_channel_1		= true,
1434 	.set_mux		= sun5i_a13_tcon_set_mux,
1435 };
1436 
1437 static const struct sun4i_tcon_quirks sun6i_a31_quirks = {
1438 	.has_channel_0		= true,
1439 	.has_channel_1		= true,
1440 	.has_lvds_alt		= true,
1441 	.needs_de_be_mux	= true,
1442 	.set_mux		= sun6i_tcon_set_mux,
1443 };
1444 
1445 static const struct sun4i_tcon_quirks sun6i_a31s_quirks = {
1446 	.has_channel_0		= true,
1447 	.has_channel_1		= true,
1448 	.needs_de_be_mux	= true,
1449 };
1450 
1451 static const struct sun4i_tcon_quirks sun7i_a20_quirks = {
1452 	.has_channel_0		= true,
1453 	.has_channel_1		= true,
1454 	/* Same display pipeline structure as A10 */
1455 	.set_mux		= sun4i_a10_tcon_set_mux,
1456 };
1457 
1458 static const struct sun4i_tcon_quirks sun8i_a33_quirks = {
1459 	.has_channel_0		= true,
1460 	.has_lvds_alt		= true,
1461 };
1462 
1463 static const struct sun4i_tcon_quirks sun8i_a83t_lcd_quirks = {
1464 	.supports_lvds		= true,
1465 	.has_channel_0		= true,
1466 };
1467 
1468 static const struct sun4i_tcon_quirks sun8i_a83t_tv_quirks = {
1469 	.has_channel_1		= true,
1470 };
1471 
1472 static const struct sun4i_tcon_quirks sun8i_r40_tv_quirks = {
1473 	.has_channel_1		= true,
1474 	.set_mux		= sun8i_r40_tcon_tv_set_mux,
1475 };
1476 
1477 static const struct sun4i_tcon_quirks sun8i_v3s_quirks = {
1478 	.has_channel_0		= true,
1479 };
1480 
1481 static const struct sun4i_tcon_quirks sun9i_a80_tcon_lcd_quirks = {
1482 	.has_channel_0	= true,
1483 	.needs_edp_reset = true,
1484 };
1485 
1486 static const struct sun4i_tcon_quirks sun9i_a80_tcon_tv_quirks = {
1487 	.has_channel_1	= true,
1488 	.needs_edp_reset = true,
1489 };
1490 
1491 /* sun4i_drv uses this list to check if a device node is a TCON */
1492 const struct of_device_id sun4i_tcon_of_table[] = {
1493 	{ .compatible = "allwinner,sun4i-a10-tcon", .data = &sun4i_a10_quirks },
1494 	{ .compatible = "allwinner,sun5i-a13-tcon", .data = &sun5i_a13_quirks },
1495 	{ .compatible = "allwinner,sun6i-a31-tcon", .data = &sun6i_a31_quirks },
1496 	{ .compatible = "allwinner,sun6i-a31s-tcon", .data = &sun6i_a31s_quirks },
1497 	{ .compatible = "allwinner,sun7i-a20-tcon", .data = &sun7i_a20_quirks },
1498 	{ .compatible = "allwinner,sun8i-a23-tcon", .data = &sun8i_a33_quirks },
1499 	{ .compatible = "allwinner,sun8i-a33-tcon", .data = &sun8i_a33_quirks },
1500 	{ .compatible = "allwinner,sun8i-a83t-tcon-lcd", .data = &sun8i_a83t_lcd_quirks },
1501 	{ .compatible = "allwinner,sun8i-a83t-tcon-tv", .data = &sun8i_a83t_tv_quirks },
1502 	{ .compatible = "allwinner,sun8i-r40-tcon-tv", .data = &sun8i_r40_tv_quirks },
1503 	{ .compatible = "allwinner,sun8i-v3s-tcon", .data = &sun8i_v3s_quirks },
1504 	{ .compatible = "allwinner,sun9i-a80-tcon-lcd", .data = &sun9i_a80_tcon_lcd_quirks },
1505 	{ .compatible = "allwinner,sun9i-a80-tcon-tv", .data = &sun9i_a80_tcon_tv_quirks },
1506 	{ }
1507 };
1508 MODULE_DEVICE_TABLE(of, sun4i_tcon_of_table);
1509 EXPORT_SYMBOL(sun4i_tcon_of_table);
1510 
1511 static struct platform_driver sun4i_tcon_platform_driver = {
1512 	.probe		= sun4i_tcon_probe,
1513 	.remove		= sun4i_tcon_remove,
1514 	.driver		= {
1515 		.name		= "sun4i-tcon",
1516 		.of_match_table	= sun4i_tcon_of_table,
1517 	},
1518 };
1519 module_platform_driver(sun4i_tcon_platform_driver);
1520 
1521 MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
1522 MODULE_DESCRIPTION("Allwinner A10 Timing Controller Driver");
1523 MODULE_LICENSE("GPL");
1524