xref: /openbmc/linux/drivers/gpu/drm/sun4i/sun4i_tcon.c (revision 6c33a6f4)
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_bridge.h>
20 #include <drm/drm_connector.h>
21 #include <drm/drm_crtc.h>
22 #include <drm/drm_encoder.h>
23 #include <drm/drm_modes.h>
24 #include <drm/drm_of.h>
25 #include <drm/drm_panel.h>
26 #include <drm/drm_print.h>
27 #include <drm/drm_probe_helper.h>
28 #include <drm/drm_vblank.h>
29 
30 #include <uapi/drm/drm_mode.h>
31 
32 #include "sun4i_crtc.h"
33 #include "sun4i_dotclock.h"
34 #include "sun4i_drv.h"
35 #include "sun4i_lvds.h"
36 #include "sun4i_rgb.h"
37 #include "sun4i_tcon.h"
38 #include "sun6i_mipi_dsi.h"
39 #include "sun8i_tcon_top.h"
40 #include "sunxi_engine.h"
41 
42 static struct drm_connector *sun4i_tcon_get_connector(const struct drm_encoder *encoder)
43 {
44 	struct drm_connector *connector;
45 	struct drm_connector_list_iter iter;
46 
47 	drm_connector_list_iter_begin(encoder->dev, &iter);
48 	drm_for_each_connector_iter(connector, &iter)
49 		if (connector->encoder == encoder) {
50 			drm_connector_list_iter_end(&iter);
51 			return connector;
52 		}
53 	drm_connector_list_iter_end(&iter);
54 
55 	return NULL;
56 }
57 
58 static int sun4i_tcon_get_pixel_depth(const struct drm_encoder *encoder)
59 {
60 	struct drm_connector *connector;
61 	struct drm_display_info *info;
62 
63 	connector = sun4i_tcon_get_connector(encoder);
64 	if (!connector)
65 		return -EINVAL;
66 
67 	info = &connector->display_info;
68 	if (info->num_bus_formats != 1)
69 		return -EINVAL;
70 
71 	switch (info->bus_formats[0]) {
72 	case MEDIA_BUS_FMT_RGB666_1X7X3_SPWG:
73 		return 18;
74 
75 	case MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA:
76 	case MEDIA_BUS_FMT_RGB888_1X7X4_SPWG:
77 		return 24;
78 	}
79 
80 	return -EINVAL;
81 }
82 
83 static void sun4i_tcon_channel_set_status(struct sun4i_tcon *tcon, int channel,
84 					  bool enabled)
85 {
86 	struct clk *clk;
87 
88 	switch (channel) {
89 	case 0:
90 		WARN_ON(!tcon->quirks->has_channel_0);
91 		regmap_update_bits(tcon->regs, SUN4I_TCON0_CTL_REG,
92 				   SUN4I_TCON0_CTL_TCON_ENABLE,
93 				   enabled ? SUN4I_TCON0_CTL_TCON_ENABLE : 0);
94 		clk = tcon->dclk;
95 		break;
96 	case 1:
97 		WARN_ON(!tcon->quirks->has_channel_1);
98 		regmap_update_bits(tcon->regs, SUN4I_TCON1_CTL_REG,
99 				   SUN4I_TCON1_CTL_TCON_ENABLE,
100 				   enabled ? SUN4I_TCON1_CTL_TCON_ENABLE : 0);
101 		clk = tcon->sclk1;
102 		break;
103 	default:
104 		DRM_WARN("Unknown channel... doing nothing\n");
105 		return;
106 	}
107 
108 	if (enabled) {
109 		clk_prepare_enable(clk);
110 		clk_rate_exclusive_get(clk);
111 	} else {
112 		clk_rate_exclusive_put(clk);
113 		clk_disable_unprepare(clk);
114 	}
115 }
116 
117 static void sun4i_tcon_setup_lvds_phy(struct sun4i_tcon *tcon,
118 				      const struct drm_encoder *encoder)
119 {
120 	regmap_write(tcon->regs, SUN4I_TCON0_LVDS_ANA0_REG,
121 		     SUN4I_TCON0_LVDS_ANA0_CK_EN |
122 		     SUN4I_TCON0_LVDS_ANA0_REG_V |
123 		     SUN4I_TCON0_LVDS_ANA0_REG_C |
124 		     SUN4I_TCON0_LVDS_ANA0_EN_MB |
125 		     SUN4I_TCON0_LVDS_ANA0_PD |
126 		     SUN4I_TCON0_LVDS_ANA0_DCHS);
127 
128 	udelay(2); /* delay at least 1200 ns */
129 	regmap_update_bits(tcon->regs, SUN4I_TCON0_LVDS_ANA1_REG,
130 			   SUN4I_TCON0_LVDS_ANA1_INIT,
131 			   SUN4I_TCON0_LVDS_ANA1_INIT);
132 	udelay(1); /* delay at least 120 ns */
133 	regmap_update_bits(tcon->regs, SUN4I_TCON0_LVDS_ANA1_REG,
134 			   SUN4I_TCON0_LVDS_ANA1_UPDATE,
135 			   SUN4I_TCON0_LVDS_ANA1_UPDATE);
136 	regmap_update_bits(tcon->regs, SUN4I_TCON0_LVDS_ANA0_REG,
137 			   SUN4I_TCON0_LVDS_ANA0_EN_MB,
138 			   SUN4I_TCON0_LVDS_ANA0_EN_MB);
139 }
140 
141 static void sun6i_tcon_setup_lvds_phy(struct sun4i_tcon *tcon,
142 				      const struct drm_encoder *encoder)
143 {
144 	u8 val;
145 
146 	regmap_write(tcon->regs, SUN4I_TCON0_LVDS_ANA0_REG,
147 		     SUN6I_TCON0_LVDS_ANA0_C(2) |
148 		     SUN6I_TCON0_LVDS_ANA0_V(3) |
149 		     SUN6I_TCON0_LVDS_ANA0_PD(2) |
150 		     SUN6I_TCON0_LVDS_ANA0_EN_LDO);
151 	udelay(2);
152 
153 	regmap_update_bits(tcon->regs, SUN4I_TCON0_LVDS_ANA0_REG,
154 			   SUN6I_TCON0_LVDS_ANA0_EN_MB,
155 			   SUN6I_TCON0_LVDS_ANA0_EN_MB);
156 	udelay(2);
157 
158 	regmap_update_bits(tcon->regs, SUN4I_TCON0_LVDS_ANA0_REG,
159 			   SUN6I_TCON0_LVDS_ANA0_EN_DRVC,
160 			   SUN6I_TCON0_LVDS_ANA0_EN_DRVC);
161 
162 	if (sun4i_tcon_get_pixel_depth(encoder) == 18)
163 		val = 7;
164 	else
165 		val = 0xf;
166 
167 	regmap_write_bits(tcon->regs, SUN4I_TCON0_LVDS_ANA0_REG,
168 			  SUN6I_TCON0_LVDS_ANA0_EN_DRVD(0xf),
169 			  SUN6I_TCON0_LVDS_ANA0_EN_DRVD(val));
170 }
171 
172 static void sun4i_tcon_lvds_set_status(struct sun4i_tcon *tcon,
173 				       const struct drm_encoder *encoder,
174 				       bool enabled)
175 {
176 	if (enabled) {
177 		regmap_update_bits(tcon->regs, SUN4I_TCON0_LVDS_IF_REG,
178 				   SUN4I_TCON0_LVDS_IF_EN,
179 				   SUN4I_TCON0_LVDS_IF_EN);
180 		if (tcon->quirks->setup_lvds_phy)
181 			tcon->quirks->setup_lvds_phy(tcon, encoder);
182 	} else {
183 		regmap_update_bits(tcon->regs, SUN4I_TCON0_LVDS_IF_REG,
184 				   SUN4I_TCON0_LVDS_IF_EN, 0);
185 	}
186 }
187 
188 void sun4i_tcon_set_status(struct sun4i_tcon *tcon,
189 			   const struct drm_encoder *encoder,
190 			   bool enabled)
191 {
192 	bool is_lvds = false;
193 	int channel;
194 
195 	switch (encoder->encoder_type) {
196 	case DRM_MODE_ENCODER_LVDS:
197 		is_lvds = true;
198 		/* Fallthrough */
199 	case DRM_MODE_ENCODER_DSI:
200 	case DRM_MODE_ENCODER_NONE:
201 		channel = 0;
202 		break;
203 	case DRM_MODE_ENCODER_TMDS:
204 	case DRM_MODE_ENCODER_TVDAC:
205 		channel = 1;
206 		break;
207 	default:
208 		DRM_DEBUG_DRIVER("Unknown encoder type, doing nothing...\n");
209 		return;
210 	}
211 
212 	if (is_lvds && !enabled)
213 		sun4i_tcon_lvds_set_status(tcon, encoder, false);
214 
215 	regmap_update_bits(tcon->regs, SUN4I_TCON_GCTL_REG,
216 			   SUN4I_TCON_GCTL_TCON_ENABLE,
217 			   enabled ? SUN4I_TCON_GCTL_TCON_ENABLE : 0);
218 
219 	if (is_lvds && enabled)
220 		sun4i_tcon_lvds_set_status(tcon, encoder, true);
221 
222 	sun4i_tcon_channel_set_status(tcon, channel, enabled);
223 }
224 
225 void sun4i_tcon_enable_vblank(struct sun4i_tcon *tcon, bool enable)
226 {
227 	u32 mask, val = 0;
228 
229 	DRM_DEBUG_DRIVER("%sabling VBLANK interrupt\n", enable ? "En" : "Dis");
230 
231 	mask = SUN4I_TCON_GINT0_VBLANK_ENABLE(0) |
232 		SUN4I_TCON_GINT0_VBLANK_ENABLE(1) |
233 		SUN4I_TCON_GINT0_TCON0_TRI_FINISH_ENABLE;
234 
235 	if (enable)
236 		val = mask;
237 
238 	regmap_update_bits(tcon->regs, SUN4I_TCON_GINT0_REG, mask, val);
239 }
240 EXPORT_SYMBOL(sun4i_tcon_enable_vblank);
241 
242 /*
243  * This function is a helper for TCON output muxing. The TCON output
244  * muxing control register in earlier SoCs (without the TCON TOP block)
245  * are located in TCON0. This helper returns a pointer to TCON0's
246  * sun4i_tcon structure, or NULL if not found.
247  */
248 static struct sun4i_tcon *sun4i_get_tcon0(struct drm_device *drm)
249 {
250 	struct sun4i_drv *drv = drm->dev_private;
251 	struct sun4i_tcon *tcon;
252 
253 	list_for_each_entry(tcon, &drv->tcon_list, list)
254 		if (tcon->id == 0)
255 			return tcon;
256 
257 	dev_warn(drm->dev,
258 		 "TCON0 not found, display output muxing may not work\n");
259 
260 	return NULL;
261 }
262 
263 static void sun4i_tcon_set_mux(struct sun4i_tcon *tcon, int channel,
264 			       const struct drm_encoder *encoder)
265 {
266 	int ret = -ENOTSUPP;
267 
268 	if (tcon->quirks->set_mux)
269 		ret = tcon->quirks->set_mux(tcon, encoder);
270 
271 	DRM_DEBUG_DRIVER("Muxing encoder %s to CRTC %s: %d\n",
272 			 encoder->name, encoder->crtc->name, ret);
273 }
274 
275 static int sun4i_tcon_get_clk_delay(const struct drm_display_mode *mode,
276 				    int channel)
277 {
278 	int delay = mode->vtotal - mode->vdisplay;
279 
280 	if (mode->flags & DRM_MODE_FLAG_INTERLACE)
281 		delay /= 2;
282 
283 	if (channel == 1)
284 		delay -= 2;
285 
286 	delay = min(delay, 30);
287 
288 	DRM_DEBUG_DRIVER("TCON %d clock delay %u\n", channel, delay);
289 
290 	return delay;
291 }
292 
293 static void sun4i_tcon0_mode_set_common(struct sun4i_tcon *tcon,
294 					const struct drm_display_mode *mode)
295 {
296 	/* Configure the dot clock */
297 	clk_set_rate(tcon->dclk, mode->crtc_clock * 1000);
298 
299 	/* Set the resolution */
300 	regmap_write(tcon->regs, SUN4I_TCON0_BASIC0_REG,
301 		     SUN4I_TCON0_BASIC0_X(mode->crtc_hdisplay) |
302 		     SUN4I_TCON0_BASIC0_Y(mode->crtc_vdisplay));
303 }
304 
305 static void sun4i_tcon0_mode_set_dithering(struct sun4i_tcon *tcon,
306 					   const struct drm_connector *connector)
307 {
308 	u32 bus_format = 0;
309 	u32 val = 0;
310 
311 	/* XXX Would this ever happen? */
312 	if (!connector)
313 		return;
314 
315 	/*
316 	 * FIXME: Undocumented bits
317 	 *
318 	 * The whole dithering process and these parameters are not
319 	 * explained in the vendor documents or BSP kernel code.
320 	 */
321 	regmap_write(tcon->regs, SUN4I_TCON0_FRM_SEED_PR_REG, 0x11111111);
322 	regmap_write(tcon->regs, SUN4I_TCON0_FRM_SEED_PG_REG, 0x11111111);
323 	regmap_write(tcon->regs, SUN4I_TCON0_FRM_SEED_PB_REG, 0x11111111);
324 	regmap_write(tcon->regs, SUN4I_TCON0_FRM_SEED_LR_REG, 0x11111111);
325 	regmap_write(tcon->regs, SUN4I_TCON0_FRM_SEED_LG_REG, 0x11111111);
326 	regmap_write(tcon->regs, SUN4I_TCON0_FRM_SEED_LB_REG, 0x11111111);
327 	regmap_write(tcon->regs, SUN4I_TCON0_FRM_TBL0_REG, 0x01010000);
328 	regmap_write(tcon->regs, SUN4I_TCON0_FRM_TBL1_REG, 0x15151111);
329 	regmap_write(tcon->regs, SUN4I_TCON0_FRM_TBL2_REG, 0x57575555);
330 	regmap_write(tcon->regs, SUN4I_TCON0_FRM_TBL3_REG, 0x7f7f7777);
331 
332 	/* Do dithering if panel only supports 6 bits per color */
333 	if (connector->display_info.bpc == 6)
334 		val |= SUN4I_TCON0_FRM_CTL_EN;
335 
336 	if (connector->display_info.num_bus_formats == 1)
337 		bus_format = connector->display_info.bus_formats[0];
338 
339 	/* Check the connection format */
340 	switch (bus_format) {
341 	case MEDIA_BUS_FMT_RGB565_1X16:
342 		/* R and B components are only 5 bits deep */
343 		val |= SUN4I_TCON0_FRM_CTL_MODE_R;
344 		val |= SUN4I_TCON0_FRM_CTL_MODE_B;
345 		/* Fall through */
346 	case MEDIA_BUS_FMT_RGB666_1X18:
347 	case MEDIA_BUS_FMT_RGB666_1X7X3_SPWG:
348 		/* Fall through: enable dithering */
349 		val |= SUN4I_TCON0_FRM_CTL_EN;
350 		break;
351 	}
352 
353 	/* Write dithering settings */
354 	regmap_write(tcon->regs, SUN4I_TCON_FRM_CTL_REG, val);
355 }
356 
357 static void sun4i_tcon0_mode_set_cpu(struct sun4i_tcon *tcon,
358 				     const struct drm_encoder *encoder,
359 				     const struct drm_display_mode *mode)
360 {
361 	/* TODO support normal CPU interface modes */
362 	struct sun6i_dsi *dsi = encoder_to_sun6i_dsi(encoder);
363 	struct mipi_dsi_device *device = dsi->device;
364 	u8 bpp = mipi_dsi_pixel_format_to_bpp(device->format);
365 	u8 lanes = device->lanes;
366 	u32 block_space, start_delay;
367 	u32 tcon_div;
368 
369 	tcon->dclk_min_div = SUN6I_DSI_TCON_DIV;
370 	tcon->dclk_max_div = SUN6I_DSI_TCON_DIV;
371 
372 	sun4i_tcon0_mode_set_common(tcon, mode);
373 
374 	/* Set dithering if needed */
375 	sun4i_tcon0_mode_set_dithering(tcon, sun4i_tcon_get_connector(encoder));
376 
377 	regmap_update_bits(tcon->regs, SUN4I_TCON0_CTL_REG,
378 			   SUN4I_TCON0_CTL_IF_MASK,
379 			   SUN4I_TCON0_CTL_IF_8080);
380 
381 	regmap_write(tcon->regs, SUN4I_TCON_ECC_FIFO_REG,
382 		     SUN4I_TCON_ECC_FIFO_EN);
383 
384 	regmap_write(tcon->regs, SUN4I_TCON0_CPU_IF_REG,
385 		     SUN4I_TCON0_CPU_IF_MODE_DSI |
386 		     SUN4I_TCON0_CPU_IF_TRI_FIFO_FLUSH |
387 		     SUN4I_TCON0_CPU_IF_TRI_FIFO_EN |
388 		     SUN4I_TCON0_CPU_IF_TRI_EN);
389 
390 	/*
391 	 * This looks suspicious, but it works...
392 	 *
393 	 * The datasheet says that this should be set higher than 20 *
394 	 * pixel cycle, but it's not clear what a pixel cycle is.
395 	 */
396 	regmap_read(tcon->regs, SUN4I_TCON0_DCLK_REG, &tcon_div);
397 	tcon_div &= GENMASK(6, 0);
398 	block_space = mode->htotal * bpp / (tcon_div * lanes);
399 	block_space -= mode->hdisplay + 40;
400 
401 	regmap_write(tcon->regs, SUN4I_TCON0_CPU_TRI0_REG,
402 		     SUN4I_TCON0_CPU_TRI0_BLOCK_SPACE(block_space) |
403 		     SUN4I_TCON0_CPU_TRI0_BLOCK_SIZE(mode->hdisplay));
404 
405 	regmap_write(tcon->regs, SUN4I_TCON0_CPU_TRI1_REG,
406 		     SUN4I_TCON0_CPU_TRI1_BLOCK_NUM(mode->vdisplay));
407 
408 	start_delay = (mode->crtc_vtotal - mode->crtc_vdisplay - 10 - 1);
409 	start_delay = start_delay * mode->crtc_htotal * 149;
410 	start_delay = start_delay / (mode->crtc_clock / 1000) / 8;
411 	regmap_write(tcon->regs, SUN4I_TCON0_CPU_TRI2_REG,
412 		     SUN4I_TCON0_CPU_TRI2_TRANS_START_SET(10) |
413 		     SUN4I_TCON0_CPU_TRI2_START_DELAY(start_delay));
414 
415 	/*
416 	 * The Allwinner BSP has a comment that the period should be
417 	 * the display clock * 15, but uses an hardcoded 3000...
418 	 */
419 	regmap_write(tcon->regs, SUN4I_TCON_SAFE_PERIOD_REG,
420 		     SUN4I_TCON_SAFE_PERIOD_NUM(3000) |
421 		     SUN4I_TCON_SAFE_PERIOD_MODE(3));
422 
423 	/* Enable the output on the pins */
424 	regmap_write(tcon->regs, SUN4I_TCON0_IO_TRI_REG,
425 		     0xe0000000);
426 }
427 
428 static void sun4i_tcon0_mode_set_lvds(struct sun4i_tcon *tcon,
429 				      const struct drm_encoder *encoder,
430 				      const struct drm_display_mode *mode)
431 {
432 	unsigned int bp;
433 	u8 clk_delay;
434 	u32 reg, val = 0;
435 
436 	WARN_ON(!tcon->quirks->has_channel_0);
437 
438 	tcon->dclk_min_div = 7;
439 	tcon->dclk_max_div = 7;
440 	sun4i_tcon0_mode_set_common(tcon, mode);
441 
442 	/* Set dithering if needed */
443 	sun4i_tcon0_mode_set_dithering(tcon, sun4i_tcon_get_connector(encoder));
444 
445 	/* Adjust clock delay */
446 	clk_delay = sun4i_tcon_get_clk_delay(mode, 0);
447 	regmap_update_bits(tcon->regs, SUN4I_TCON0_CTL_REG,
448 			   SUN4I_TCON0_CTL_CLK_DELAY_MASK,
449 			   SUN4I_TCON0_CTL_CLK_DELAY(clk_delay));
450 
451 	/*
452 	 * This is called a backporch in the register documentation,
453 	 * but it really is the back porch + hsync
454 	 */
455 	bp = mode->crtc_htotal - mode->crtc_hsync_start;
456 	DRM_DEBUG_DRIVER("Setting horizontal total %d, backporch %d\n",
457 			 mode->crtc_htotal, bp);
458 
459 	/* Set horizontal display timings */
460 	regmap_write(tcon->regs, SUN4I_TCON0_BASIC1_REG,
461 		     SUN4I_TCON0_BASIC1_H_TOTAL(mode->htotal) |
462 		     SUN4I_TCON0_BASIC1_H_BACKPORCH(bp));
463 
464 	/*
465 	 * This is called a backporch in the register documentation,
466 	 * but it really is the back porch + hsync
467 	 */
468 	bp = mode->crtc_vtotal - mode->crtc_vsync_start;
469 	DRM_DEBUG_DRIVER("Setting vertical total %d, backporch %d\n",
470 			 mode->crtc_vtotal, bp);
471 
472 	/* Set vertical display timings */
473 	regmap_write(tcon->regs, SUN4I_TCON0_BASIC2_REG,
474 		     SUN4I_TCON0_BASIC2_V_TOTAL(mode->crtc_vtotal * 2) |
475 		     SUN4I_TCON0_BASIC2_V_BACKPORCH(bp));
476 
477 	reg = SUN4I_TCON0_LVDS_IF_CLK_SEL_TCON0 |
478 		SUN4I_TCON0_LVDS_IF_DATA_POL_NORMAL |
479 		SUN4I_TCON0_LVDS_IF_CLK_POL_NORMAL;
480 	if (sun4i_tcon_get_pixel_depth(encoder) == 24)
481 		reg |= SUN4I_TCON0_LVDS_IF_BITWIDTH_24BITS;
482 	else
483 		reg |= SUN4I_TCON0_LVDS_IF_BITWIDTH_18BITS;
484 
485 	regmap_write(tcon->regs, SUN4I_TCON0_LVDS_IF_REG, reg);
486 
487 	/* Setup the polarity of the various signals */
488 	if (!(mode->flags & DRM_MODE_FLAG_PHSYNC))
489 		val |= SUN4I_TCON0_IO_POL_HSYNC_POSITIVE;
490 
491 	if (!(mode->flags & DRM_MODE_FLAG_PVSYNC))
492 		val |= SUN4I_TCON0_IO_POL_VSYNC_POSITIVE;
493 
494 	regmap_write(tcon->regs, SUN4I_TCON0_IO_POL_REG, val);
495 
496 	/* Map output pins to channel 0 */
497 	regmap_update_bits(tcon->regs, SUN4I_TCON_GCTL_REG,
498 			   SUN4I_TCON_GCTL_IOMAP_MASK,
499 			   SUN4I_TCON_GCTL_IOMAP_TCON0);
500 
501 	/* Enable the output on the pins */
502 	regmap_write(tcon->regs, SUN4I_TCON0_IO_TRI_REG, 0xe0000000);
503 }
504 
505 static void sun4i_tcon0_mode_set_rgb(struct sun4i_tcon *tcon,
506 				     const struct drm_encoder *encoder,
507 				     const struct drm_display_mode *mode)
508 {
509 	struct drm_connector *connector = sun4i_tcon_get_connector(encoder);
510 	const struct drm_display_info *info = &connector->display_info;
511 	unsigned int bp, hsync, vsync;
512 	u8 clk_delay;
513 	u32 val = 0;
514 
515 	WARN_ON(!tcon->quirks->has_channel_0);
516 
517 	tcon->dclk_min_div = tcon->quirks->dclk_min_div;
518 	tcon->dclk_max_div = 127;
519 	sun4i_tcon0_mode_set_common(tcon, mode);
520 
521 	/* Set dithering if needed */
522 	sun4i_tcon0_mode_set_dithering(tcon, connector);
523 
524 	/* Adjust clock delay */
525 	clk_delay = sun4i_tcon_get_clk_delay(mode, 0);
526 	regmap_update_bits(tcon->regs, SUN4I_TCON0_CTL_REG,
527 			   SUN4I_TCON0_CTL_CLK_DELAY_MASK,
528 			   SUN4I_TCON0_CTL_CLK_DELAY(clk_delay));
529 
530 	/*
531 	 * This is called a backporch in the register documentation,
532 	 * but it really is the back porch + hsync
533 	 */
534 	bp = mode->crtc_htotal - mode->crtc_hsync_start;
535 	DRM_DEBUG_DRIVER("Setting horizontal total %d, backporch %d\n",
536 			 mode->crtc_htotal, bp);
537 
538 	/* Set horizontal display timings */
539 	regmap_write(tcon->regs, SUN4I_TCON0_BASIC1_REG,
540 		     SUN4I_TCON0_BASIC1_H_TOTAL(mode->crtc_htotal) |
541 		     SUN4I_TCON0_BASIC1_H_BACKPORCH(bp));
542 
543 	/*
544 	 * This is called a backporch in the register documentation,
545 	 * but it really is the back porch + hsync
546 	 */
547 	bp = mode->crtc_vtotal - mode->crtc_vsync_start;
548 	DRM_DEBUG_DRIVER("Setting vertical total %d, backporch %d\n",
549 			 mode->crtc_vtotal, bp);
550 
551 	/* Set vertical display timings */
552 	regmap_write(tcon->regs, SUN4I_TCON0_BASIC2_REG,
553 		     SUN4I_TCON0_BASIC2_V_TOTAL(mode->crtc_vtotal * 2) |
554 		     SUN4I_TCON0_BASIC2_V_BACKPORCH(bp));
555 
556 	/* Set Hsync and Vsync length */
557 	hsync = mode->crtc_hsync_end - mode->crtc_hsync_start;
558 	vsync = mode->crtc_vsync_end - mode->crtc_vsync_start;
559 	DRM_DEBUG_DRIVER("Setting HSYNC %d, VSYNC %d\n", hsync, vsync);
560 	regmap_write(tcon->regs, SUN4I_TCON0_BASIC3_REG,
561 		     SUN4I_TCON0_BASIC3_V_SYNC(vsync) |
562 		     SUN4I_TCON0_BASIC3_H_SYNC(hsync));
563 
564 	/* Setup the polarity of the various signals */
565 	if (mode->flags & DRM_MODE_FLAG_PHSYNC)
566 		val |= SUN4I_TCON0_IO_POL_HSYNC_POSITIVE;
567 
568 	if (mode->flags & DRM_MODE_FLAG_PVSYNC)
569 		val |= SUN4I_TCON0_IO_POL_VSYNC_POSITIVE;
570 
571 	if (info->bus_flags & DRM_BUS_FLAG_DE_LOW)
572 		val |= SUN4I_TCON0_IO_POL_DE_NEGATIVE;
573 
574 	/*
575 	 * On A20 and similar SoCs, the only way to achieve Positive Edge
576 	 * (Rising Edge), is setting dclk clock phase to 2/3(240°).
577 	 * By default TCON works in Negative Edge(Falling Edge),
578 	 * this is why phase is set to 0 in that case.
579 	 * Unfortunately there's no way to logically invert dclk through
580 	 * IO_POL register.
581 	 * The only acceptable way to work, triple checked with scope,
582 	 * is using clock phase set to 0° for Negative Edge and set to 240°
583 	 * for Positive Edge.
584 	 * On A33 and similar SoCs there would be a 90° phase option,
585 	 * but it divides also dclk by 2.
586 	 * Following code is a way to avoid quirks all around TCON
587 	 * and DOTCLOCK drivers.
588 	 */
589 	if (info->bus_flags & DRM_BUS_FLAG_PIXDATA_DRIVE_POSEDGE)
590 		clk_set_phase(tcon->dclk, 240);
591 
592 	if (info->bus_flags & DRM_BUS_FLAG_PIXDATA_DRIVE_NEGEDGE)
593 		clk_set_phase(tcon->dclk, 0);
594 
595 	regmap_update_bits(tcon->regs, SUN4I_TCON0_IO_POL_REG,
596 			   SUN4I_TCON0_IO_POL_HSYNC_POSITIVE |
597 			   SUN4I_TCON0_IO_POL_VSYNC_POSITIVE |
598 			   SUN4I_TCON0_IO_POL_DE_NEGATIVE,
599 			   val);
600 
601 	/* Map output pins to channel 0 */
602 	regmap_update_bits(tcon->regs, SUN4I_TCON_GCTL_REG,
603 			   SUN4I_TCON_GCTL_IOMAP_MASK,
604 			   SUN4I_TCON_GCTL_IOMAP_TCON0);
605 
606 	/* Enable the output on the pins */
607 	regmap_write(tcon->regs, SUN4I_TCON0_IO_TRI_REG, 0);
608 }
609 
610 static void sun4i_tcon1_mode_set(struct sun4i_tcon *tcon,
611 				 const struct drm_display_mode *mode)
612 {
613 	unsigned int bp, hsync, vsync, vtotal;
614 	u8 clk_delay;
615 	u32 val;
616 
617 	WARN_ON(!tcon->quirks->has_channel_1);
618 
619 	/* Configure the dot clock */
620 	clk_set_rate(tcon->sclk1, mode->crtc_clock * 1000);
621 
622 	/* Adjust clock delay */
623 	clk_delay = sun4i_tcon_get_clk_delay(mode, 1);
624 	regmap_update_bits(tcon->regs, SUN4I_TCON1_CTL_REG,
625 			   SUN4I_TCON1_CTL_CLK_DELAY_MASK,
626 			   SUN4I_TCON1_CTL_CLK_DELAY(clk_delay));
627 
628 	/* Set interlaced mode */
629 	if (mode->flags & DRM_MODE_FLAG_INTERLACE)
630 		val = SUN4I_TCON1_CTL_INTERLACE_ENABLE;
631 	else
632 		val = 0;
633 	regmap_update_bits(tcon->regs, SUN4I_TCON1_CTL_REG,
634 			   SUN4I_TCON1_CTL_INTERLACE_ENABLE,
635 			   val);
636 
637 	/* Set the input resolution */
638 	regmap_write(tcon->regs, SUN4I_TCON1_BASIC0_REG,
639 		     SUN4I_TCON1_BASIC0_X(mode->crtc_hdisplay) |
640 		     SUN4I_TCON1_BASIC0_Y(mode->crtc_vdisplay));
641 
642 	/* Set the upscaling resolution */
643 	regmap_write(tcon->regs, SUN4I_TCON1_BASIC1_REG,
644 		     SUN4I_TCON1_BASIC1_X(mode->crtc_hdisplay) |
645 		     SUN4I_TCON1_BASIC1_Y(mode->crtc_vdisplay));
646 
647 	/* Set the output resolution */
648 	regmap_write(tcon->regs, SUN4I_TCON1_BASIC2_REG,
649 		     SUN4I_TCON1_BASIC2_X(mode->crtc_hdisplay) |
650 		     SUN4I_TCON1_BASIC2_Y(mode->crtc_vdisplay));
651 
652 	/* Set horizontal display timings */
653 	bp = mode->crtc_htotal - mode->crtc_hsync_start;
654 	DRM_DEBUG_DRIVER("Setting horizontal total %d, backporch %d\n",
655 			 mode->htotal, bp);
656 	regmap_write(tcon->regs, SUN4I_TCON1_BASIC3_REG,
657 		     SUN4I_TCON1_BASIC3_H_TOTAL(mode->crtc_htotal) |
658 		     SUN4I_TCON1_BASIC3_H_BACKPORCH(bp));
659 
660 	bp = mode->crtc_vtotal - mode->crtc_vsync_start;
661 	DRM_DEBUG_DRIVER("Setting vertical total %d, backporch %d\n",
662 			 mode->crtc_vtotal, bp);
663 
664 	/*
665 	 * The vertical resolution needs to be doubled in all
666 	 * cases. We could use crtc_vtotal and always multiply by two,
667 	 * but that leads to a rounding error in interlace when vtotal
668 	 * is odd.
669 	 *
670 	 * This happens with TV's PAL for example, where vtotal will
671 	 * be 625, crtc_vtotal 312, and thus crtc_vtotal * 2 will be
672 	 * 624, which apparently confuses the hardware.
673 	 *
674 	 * To work around this, we will always use vtotal, and
675 	 * multiply by two only if we're not in interlace.
676 	 */
677 	vtotal = mode->vtotal;
678 	if (!(mode->flags & DRM_MODE_FLAG_INTERLACE))
679 		vtotal = vtotal * 2;
680 
681 	/* Set vertical display timings */
682 	regmap_write(tcon->regs, SUN4I_TCON1_BASIC4_REG,
683 		     SUN4I_TCON1_BASIC4_V_TOTAL(vtotal) |
684 		     SUN4I_TCON1_BASIC4_V_BACKPORCH(bp));
685 
686 	/* Set Hsync and Vsync length */
687 	hsync = mode->crtc_hsync_end - mode->crtc_hsync_start;
688 	vsync = mode->crtc_vsync_end - mode->crtc_vsync_start;
689 	DRM_DEBUG_DRIVER("Setting HSYNC %d, VSYNC %d\n", hsync, vsync);
690 	regmap_write(tcon->regs, SUN4I_TCON1_BASIC5_REG,
691 		     SUN4I_TCON1_BASIC5_V_SYNC(vsync) |
692 		     SUN4I_TCON1_BASIC5_H_SYNC(hsync));
693 
694 	/* Map output pins to channel 1 */
695 	regmap_update_bits(tcon->regs, SUN4I_TCON_GCTL_REG,
696 			   SUN4I_TCON_GCTL_IOMAP_MASK,
697 			   SUN4I_TCON_GCTL_IOMAP_TCON1);
698 }
699 
700 void sun4i_tcon_mode_set(struct sun4i_tcon *tcon,
701 			 const struct drm_encoder *encoder,
702 			 const struct drm_display_mode *mode)
703 {
704 	switch (encoder->encoder_type) {
705 	case DRM_MODE_ENCODER_DSI:
706 		/* DSI is tied to special case of CPU interface */
707 		sun4i_tcon0_mode_set_cpu(tcon, encoder, mode);
708 		break;
709 	case DRM_MODE_ENCODER_LVDS:
710 		sun4i_tcon0_mode_set_lvds(tcon, encoder, mode);
711 		break;
712 	case DRM_MODE_ENCODER_NONE:
713 		sun4i_tcon0_mode_set_rgb(tcon, encoder, mode);
714 		sun4i_tcon_set_mux(tcon, 0, encoder);
715 		break;
716 	case DRM_MODE_ENCODER_TVDAC:
717 	case DRM_MODE_ENCODER_TMDS:
718 		sun4i_tcon1_mode_set(tcon, mode);
719 		sun4i_tcon_set_mux(tcon, 1, encoder);
720 		break;
721 	default:
722 		DRM_DEBUG_DRIVER("Unknown encoder type, doing nothing...\n");
723 	}
724 }
725 EXPORT_SYMBOL(sun4i_tcon_mode_set);
726 
727 static void sun4i_tcon_finish_page_flip(struct drm_device *dev,
728 					struct sun4i_crtc *scrtc)
729 {
730 	unsigned long flags;
731 
732 	spin_lock_irqsave(&dev->event_lock, flags);
733 	if (scrtc->event) {
734 		drm_crtc_send_vblank_event(&scrtc->crtc, scrtc->event);
735 		drm_crtc_vblank_put(&scrtc->crtc);
736 		scrtc->event = NULL;
737 	}
738 	spin_unlock_irqrestore(&dev->event_lock, flags);
739 }
740 
741 static irqreturn_t sun4i_tcon_handler(int irq, void *private)
742 {
743 	struct sun4i_tcon *tcon = private;
744 	struct drm_device *drm = tcon->drm;
745 	struct sun4i_crtc *scrtc = tcon->crtc;
746 	struct sunxi_engine *engine = scrtc->engine;
747 	unsigned int status;
748 
749 	regmap_read(tcon->regs, SUN4I_TCON_GINT0_REG, &status);
750 
751 	if (!(status & (SUN4I_TCON_GINT0_VBLANK_INT(0) |
752 			SUN4I_TCON_GINT0_VBLANK_INT(1) |
753 			SUN4I_TCON_GINT0_TCON0_TRI_FINISH_INT)))
754 		return IRQ_NONE;
755 
756 	drm_crtc_handle_vblank(&scrtc->crtc);
757 	sun4i_tcon_finish_page_flip(drm, scrtc);
758 
759 	/* Acknowledge the interrupt */
760 	regmap_update_bits(tcon->regs, SUN4I_TCON_GINT0_REG,
761 			   SUN4I_TCON_GINT0_VBLANK_INT(0) |
762 			   SUN4I_TCON_GINT0_VBLANK_INT(1) |
763 			   SUN4I_TCON_GINT0_TCON0_TRI_FINISH_INT,
764 			   0);
765 
766 	if (engine->ops->vblank_quirk)
767 		engine->ops->vblank_quirk(engine);
768 
769 	return IRQ_HANDLED;
770 }
771 
772 static int sun4i_tcon_init_clocks(struct device *dev,
773 				  struct sun4i_tcon *tcon)
774 {
775 	tcon->clk = devm_clk_get(dev, "ahb");
776 	if (IS_ERR(tcon->clk)) {
777 		dev_err(dev, "Couldn't get the TCON bus clock\n");
778 		return PTR_ERR(tcon->clk);
779 	}
780 	clk_prepare_enable(tcon->clk);
781 
782 	if (tcon->quirks->has_channel_0) {
783 		tcon->sclk0 = devm_clk_get(dev, "tcon-ch0");
784 		if (IS_ERR(tcon->sclk0)) {
785 			dev_err(dev, "Couldn't get the TCON channel 0 clock\n");
786 			return PTR_ERR(tcon->sclk0);
787 		}
788 	}
789 	clk_prepare_enable(tcon->sclk0);
790 
791 	if (tcon->quirks->has_channel_1) {
792 		tcon->sclk1 = devm_clk_get(dev, "tcon-ch1");
793 		if (IS_ERR(tcon->sclk1)) {
794 			dev_err(dev, "Couldn't get the TCON channel 1 clock\n");
795 			return PTR_ERR(tcon->sclk1);
796 		}
797 	}
798 
799 	return 0;
800 }
801 
802 static void sun4i_tcon_free_clocks(struct sun4i_tcon *tcon)
803 {
804 	clk_disable_unprepare(tcon->sclk0);
805 	clk_disable_unprepare(tcon->clk);
806 }
807 
808 static int sun4i_tcon_init_irq(struct device *dev,
809 			       struct sun4i_tcon *tcon)
810 {
811 	struct platform_device *pdev = to_platform_device(dev);
812 	int irq, ret;
813 
814 	irq = platform_get_irq(pdev, 0);
815 	if (irq < 0) {
816 		dev_err(dev, "Couldn't retrieve the TCON interrupt\n");
817 		return irq;
818 	}
819 
820 	ret = devm_request_irq(dev, irq, sun4i_tcon_handler, 0,
821 			       dev_name(dev), tcon);
822 	if (ret) {
823 		dev_err(dev, "Couldn't request the IRQ\n");
824 		return ret;
825 	}
826 
827 	return 0;
828 }
829 
830 static struct regmap_config sun4i_tcon_regmap_config = {
831 	.reg_bits	= 32,
832 	.val_bits	= 32,
833 	.reg_stride	= 4,
834 	.max_register	= 0x800,
835 };
836 
837 static int sun4i_tcon_init_regmap(struct device *dev,
838 				  struct sun4i_tcon *tcon)
839 {
840 	struct platform_device *pdev = to_platform_device(dev);
841 	struct resource *res;
842 	void __iomem *regs;
843 
844 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
845 	regs = devm_ioremap_resource(dev, res);
846 	if (IS_ERR(regs))
847 		return PTR_ERR(regs);
848 
849 	tcon->regs = devm_regmap_init_mmio(dev, regs,
850 					   &sun4i_tcon_regmap_config);
851 	if (IS_ERR(tcon->regs)) {
852 		dev_err(dev, "Couldn't create the TCON regmap\n");
853 		return PTR_ERR(tcon->regs);
854 	}
855 
856 	/* Make sure the TCON is disabled and all IRQs are off */
857 	regmap_write(tcon->regs, SUN4I_TCON_GCTL_REG, 0);
858 	regmap_write(tcon->regs, SUN4I_TCON_GINT0_REG, 0);
859 	regmap_write(tcon->regs, SUN4I_TCON_GINT1_REG, 0);
860 
861 	/* Disable IO lines and set them to tristate */
862 	regmap_write(tcon->regs, SUN4I_TCON0_IO_TRI_REG, ~0);
863 	regmap_write(tcon->regs, SUN4I_TCON1_IO_TRI_REG, ~0);
864 
865 	return 0;
866 }
867 
868 /*
869  * On SoCs with the old display pipeline design (Display Engine 1.0),
870  * the TCON is always tied to just one backend. Hence we can traverse
871  * the of_graph upwards to find the backend our tcon is connected to,
872  * and take its ID as our own.
873  *
874  * We can either identify backends from their compatible strings, which
875  * means maintaining a large list of them. Or, since the backend is
876  * registered and binded before the TCON, we can just go through the
877  * list of registered backends and compare the device node.
878  *
879  * As the structures now store engines instead of backends, here this
880  * function in fact searches the corresponding engine, and the ID is
881  * requested via the get_id function of the engine.
882  */
883 static struct sunxi_engine *
884 sun4i_tcon_find_engine_traverse(struct sun4i_drv *drv,
885 				struct device_node *node,
886 				u32 port_id)
887 {
888 	struct device_node *port, *ep, *remote;
889 	struct sunxi_engine *engine = ERR_PTR(-EINVAL);
890 	u32 reg = 0;
891 
892 	port = of_graph_get_port_by_id(node, port_id);
893 	if (!port)
894 		return ERR_PTR(-EINVAL);
895 
896 	/*
897 	 * This only works if there is only one path from the TCON
898 	 * to any display engine. Otherwise the probe order of the
899 	 * TCONs and display engines is not guaranteed. They may
900 	 * either bind to the wrong one, or worse, bind to the same
901 	 * one if additional checks are not done.
902 	 *
903 	 * Bail out if there are multiple input connections.
904 	 */
905 	if (of_get_available_child_count(port) != 1)
906 		goto out_put_port;
907 
908 	/* Get the first connection without specifying an ID */
909 	ep = of_get_next_available_child(port, NULL);
910 	if (!ep)
911 		goto out_put_port;
912 
913 	remote = of_graph_get_remote_port_parent(ep);
914 	if (!remote)
915 		goto out_put_ep;
916 
917 	/* does this node match any registered engines? */
918 	list_for_each_entry(engine, &drv->engine_list, list)
919 		if (remote == engine->node)
920 			goto out_put_remote;
921 
922 	/*
923 	 * According to device tree binding input ports have even id
924 	 * number and output ports have odd id. Since component with
925 	 * more than one input and one output (TCON TOP) exits, correct
926 	 * remote input id has to be calculated by subtracting 1 from
927 	 * remote output id. If this for some reason can't be done, 0
928 	 * is used as input port id.
929 	 */
930 	of_node_put(port);
931 	port = of_graph_get_remote_port(ep);
932 	if (!of_property_read_u32(port, "reg", &reg) && reg > 0)
933 		reg -= 1;
934 
935 	/* keep looking through upstream ports */
936 	engine = sun4i_tcon_find_engine_traverse(drv, remote, reg);
937 
938 out_put_remote:
939 	of_node_put(remote);
940 out_put_ep:
941 	of_node_put(ep);
942 out_put_port:
943 	of_node_put(port);
944 
945 	return engine;
946 }
947 
948 /*
949  * The device tree binding says that the remote endpoint ID of any
950  * connection between components, up to and including the TCON, of
951  * the display pipeline should be equal to the actual ID of the local
952  * component. Thus we can look at any one of the input connections of
953  * the TCONs, and use that connection's remote endpoint ID as our own.
954  *
955  * Since the user of this function already finds the input port,
956  * the port is passed in directly without further checks.
957  */
958 static int sun4i_tcon_of_get_id_from_port(struct device_node *port)
959 {
960 	struct device_node *ep;
961 	int ret = -EINVAL;
962 
963 	/* try finding an upstream endpoint */
964 	for_each_available_child_of_node(port, ep) {
965 		struct device_node *remote;
966 		u32 reg;
967 
968 		remote = of_graph_get_remote_endpoint(ep);
969 		if (!remote)
970 			continue;
971 
972 		ret = of_property_read_u32(remote, "reg", &reg);
973 		if (ret)
974 			continue;
975 
976 		ret = reg;
977 	}
978 
979 	return ret;
980 }
981 
982 /*
983  * Once we know the TCON's id, we can look through the list of
984  * engines to find a matching one. We assume all engines have
985  * been probed and added to the list.
986  */
987 static struct sunxi_engine *sun4i_tcon_get_engine_by_id(struct sun4i_drv *drv,
988 							int id)
989 {
990 	struct sunxi_engine *engine;
991 
992 	list_for_each_entry(engine, &drv->engine_list, list)
993 		if (engine->id == id)
994 			return engine;
995 
996 	return ERR_PTR(-EINVAL);
997 }
998 
999 static bool sun4i_tcon_connected_to_tcon_top(struct device_node *node)
1000 {
1001 	struct device_node *remote;
1002 	bool ret = false;
1003 
1004 	remote = of_graph_get_remote_node(node, 0, -1);
1005 	if (remote) {
1006 		ret = !!(IS_ENABLED(CONFIG_DRM_SUN8I_TCON_TOP) &&
1007 			 of_match_node(sun8i_tcon_top_of_table, remote));
1008 		of_node_put(remote);
1009 	}
1010 
1011 	return ret;
1012 }
1013 
1014 static int sun4i_tcon_get_index(struct sun4i_drv *drv)
1015 {
1016 	struct list_head *pos;
1017 	int size = 0;
1018 
1019 	/*
1020 	 * Because TCON is added to the list at the end of the probe
1021 	 * (after this function is called), index of the current TCON
1022 	 * will be same as current TCON list size.
1023 	 */
1024 	list_for_each(pos, &drv->tcon_list)
1025 		++size;
1026 
1027 	return size;
1028 }
1029 
1030 /*
1031  * On SoCs with the old display pipeline design (Display Engine 1.0),
1032  * we assumed the TCON was always tied to just one backend. However
1033  * this proved not to be the case. On the A31, the TCON can select
1034  * either backend as its source. On the A20 (and likely on the A10),
1035  * the backend can choose which TCON to output to.
1036  *
1037  * The device tree binding says that the remote endpoint ID of any
1038  * connection between components, up to and including the TCON, of
1039  * the display pipeline should be equal to the actual ID of the local
1040  * component. Thus we should be able to look at any one of the input
1041  * connections of the TCONs, and use that connection's remote endpoint
1042  * ID as our own.
1043  *
1044  * However  the connections between the backend and TCON were assumed
1045  * to be always singular, and their endpoit IDs were all incorrectly
1046  * set to 0. This means for these old device trees, we cannot just look
1047  * up the remote endpoint ID of a TCON input endpoint. TCON1 would be
1048  * incorrectly identified as TCON0.
1049  *
1050  * This function first checks if the TCON node has 2 input endpoints.
1051  * If so, then the device tree is a corrected version, and it will use
1052  * sun4i_tcon_of_get_id() and sun4i_tcon_get_engine_by_id() from above
1053  * to fetch the ID and engine directly. If not, then it is likely an
1054  * old device trees, where the endpoint IDs were incorrect, but did not
1055  * have endpoint connections between the backend and TCON across
1056  * different display pipelines. It will fall back to the old method of
1057  * traversing the  of_graph to try and find a matching engine by device
1058  * node.
1059  *
1060  * In the case of single display pipeline device trees, either method
1061  * works.
1062  */
1063 static struct sunxi_engine *sun4i_tcon_find_engine(struct sun4i_drv *drv,
1064 						   struct device_node *node)
1065 {
1066 	struct device_node *port;
1067 	struct sunxi_engine *engine;
1068 
1069 	port = of_graph_get_port_by_id(node, 0);
1070 	if (!port)
1071 		return ERR_PTR(-EINVAL);
1072 
1073 	/*
1074 	 * Is this a corrected device tree with cross pipeline
1075 	 * connections between the backend and TCON?
1076 	 */
1077 	if (of_get_child_count(port) > 1) {
1078 		int id;
1079 
1080 		/*
1081 		 * When pipeline has the same number of TCONs and engines which
1082 		 * are represented by frontends/backends (DE1) or mixers (DE2),
1083 		 * we match them by their respective IDs. However, if pipeline
1084 		 * contains TCON TOP, chances are that there are either more
1085 		 * TCONs than engines (R40) or TCONs with non-consecutive ids.
1086 		 * (H6). In that case it's easier just use TCON index in list
1087 		 * as an id. That means that on R40, any 2 TCONs can be enabled
1088 		 * in DT out of 4 (there are 2 mixers). Due to the design of
1089 		 * TCON TOP, remaining 2 TCONs can't be connected to anything
1090 		 * anyway.
1091 		 */
1092 		if (sun4i_tcon_connected_to_tcon_top(node))
1093 			id = sun4i_tcon_get_index(drv);
1094 		else
1095 			id = sun4i_tcon_of_get_id_from_port(port);
1096 
1097 		/* Get our engine by matching our ID */
1098 		engine = sun4i_tcon_get_engine_by_id(drv, id);
1099 
1100 		of_node_put(port);
1101 		return engine;
1102 	}
1103 
1104 	/* Fallback to old method by traversing input endpoints */
1105 	of_node_put(port);
1106 	return sun4i_tcon_find_engine_traverse(drv, node, 0);
1107 }
1108 
1109 static int sun4i_tcon_bind(struct device *dev, struct device *master,
1110 			   void *data)
1111 {
1112 	struct drm_device *drm = data;
1113 	struct sun4i_drv *drv = drm->dev_private;
1114 	struct sunxi_engine *engine;
1115 	struct device_node *remote;
1116 	struct sun4i_tcon *tcon;
1117 	struct reset_control *edp_rstc;
1118 	bool has_lvds_rst, has_lvds_alt, can_lvds;
1119 	int ret;
1120 
1121 	engine = sun4i_tcon_find_engine(drv, dev->of_node);
1122 	if (IS_ERR(engine)) {
1123 		dev_err(dev, "Couldn't find matching engine\n");
1124 		return -EPROBE_DEFER;
1125 	}
1126 
1127 	tcon = devm_kzalloc(dev, sizeof(*tcon), GFP_KERNEL);
1128 	if (!tcon)
1129 		return -ENOMEM;
1130 	dev_set_drvdata(dev, tcon);
1131 	tcon->drm = drm;
1132 	tcon->dev = dev;
1133 	tcon->id = engine->id;
1134 	tcon->quirks = of_device_get_match_data(dev);
1135 
1136 	tcon->lcd_rst = devm_reset_control_get(dev, "lcd");
1137 	if (IS_ERR(tcon->lcd_rst)) {
1138 		dev_err(dev, "Couldn't get our reset line\n");
1139 		return PTR_ERR(tcon->lcd_rst);
1140 	}
1141 
1142 	if (tcon->quirks->needs_edp_reset) {
1143 		edp_rstc = devm_reset_control_get_shared(dev, "edp");
1144 		if (IS_ERR(edp_rstc)) {
1145 			dev_err(dev, "Couldn't get edp reset line\n");
1146 			return PTR_ERR(edp_rstc);
1147 		}
1148 
1149 		ret = reset_control_deassert(edp_rstc);
1150 		if (ret) {
1151 			dev_err(dev, "Couldn't deassert edp reset line\n");
1152 			return ret;
1153 		}
1154 	}
1155 
1156 	/* Make sure our TCON is reset */
1157 	ret = reset_control_reset(tcon->lcd_rst);
1158 	if (ret) {
1159 		dev_err(dev, "Couldn't deassert our reset line\n");
1160 		return ret;
1161 	}
1162 
1163 	if (tcon->quirks->supports_lvds) {
1164 		/*
1165 		 * This can only be made optional since we've had DT
1166 		 * nodes without the LVDS reset properties.
1167 		 *
1168 		 * If the property is missing, just disable LVDS, and
1169 		 * print a warning.
1170 		 */
1171 		tcon->lvds_rst = devm_reset_control_get_optional(dev, "lvds");
1172 		if (IS_ERR(tcon->lvds_rst)) {
1173 			dev_err(dev, "Couldn't get our reset line\n");
1174 			return PTR_ERR(tcon->lvds_rst);
1175 		} else if (tcon->lvds_rst) {
1176 			has_lvds_rst = true;
1177 			reset_control_reset(tcon->lvds_rst);
1178 		} else {
1179 			has_lvds_rst = false;
1180 		}
1181 
1182 		/*
1183 		 * This can only be made optional since we've had DT
1184 		 * nodes without the LVDS reset properties.
1185 		 *
1186 		 * If the property is missing, just disable LVDS, and
1187 		 * print a warning.
1188 		 */
1189 		if (tcon->quirks->has_lvds_alt) {
1190 			tcon->lvds_pll = devm_clk_get(dev, "lvds-alt");
1191 			if (IS_ERR(tcon->lvds_pll)) {
1192 				if (PTR_ERR(tcon->lvds_pll) == -ENOENT) {
1193 					has_lvds_alt = false;
1194 				} else {
1195 					dev_err(dev, "Couldn't get the LVDS PLL\n");
1196 					return PTR_ERR(tcon->lvds_pll);
1197 				}
1198 			} else {
1199 				has_lvds_alt = true;
1200 			}
1201 		}
1202 
1203 		if (!has_lvds_rst ||
1204 		    (tcon->quirks->has_lvds_alt && !has_lvds_alt)) {
1205 			dev_warn(dev, "Missing LVDS properties, Please upgrade your DT\n");
1206 			dev_warn(dev, "LVDS output disabled\n");
1207 			can_lvds = false;
1208 		} else {
1209 			can_lvds = true;
1210 		}
1211 	} else {
1212 		can_lvds = false;
1213 	}
1214 
1215 	ret = sun4i_tcon_init_clocks(dev, tcon);
1216 	if (ret) {
1217 		dev_err(dev, "Couldn't init our TCON clocks\n");
1218 		goto err_assert_reset;
1219 	}
1220 
1221 	ret = sun4i_tcon_init_regmap(dev, tcon);
1222 	if (ret) {
1223 		dev_err(dev, "Couldn't init our TCON regmap\n");
1224 		goto err_free_clocks;
1225 	}
1226 
1227 	if (tcon->quirks->has_channel_0) {
1228 		ret = sun4i_dclk_create(dev, tcon);
1229 		if (ret) {
1230 			dev_err(dev, "Couldn't create our TCON dot clock\n");
1231 			goto err_free_clocks;
1232 		}
1233 	}
1234 
1235 	ret = sun4i_tcon_init_irq(dev, tcon);
1236 	if (ret) {
1237 		dev_err(dev, "Couldn't init our TCON interrupts\n");
1238 		goto err_free_dotclock;
1239 	}
1240 
1241 	tcon->crtc = sun4i_crtc_init(drm, engine, tcon);
1242 	if (IS_ERR(tcon->crtc)) {
1243 		dev_err(dev, "Couldn't create our CRTC\n");
1244 		ret = PTR_ERR(tcon->crtc);
1245 		goto err_free_dotclock;
1246 	}
1247 
1248 	if (tcon->quirks->has_channel_0) {
1249 		/*
1250 		 * If we have an LVDS panel connected to the TCON, we should
1251 		 * just probe the LVDS connector. Otherwise, just probe RGB as
1252 		 * we used to.
1253 		 */
1254 		remote = of_graph_get_remote_node(dev->of_node, 1, 0);
1255 		if (of_device_is_compatible(remote, "panel-lvds"))
1256 			if (can_lvds)
1257 				ret = sun4i_lvds_init(drm, tcon);
1258 			else
1259 				ret = -EINVAL;
1260 		else
1261 			ret = sun4i_rgb_init(drm, tcon);
1262 		of_node_put(remote);
1263 
1264 		if (ret < 0)
1265 			goto err_free_dotclock;
1266 	}
1267 
1268 	if (tcon->quirks->needs_de_be_mux) {
1269 		/*
1270 		 * We assume there is no dynamic muxing of backends
1271 		 * and TCONs, so we select the backend with same ID.
1272 		 *
1273 		 * While dynamic selection might be interesting, since
1274 		 * the CRTC is tied to the TCON, while the layers are
1275 		 * tied to the backends, this means, we will need to
1276 		 * switch between groups of layers. There might not be
1277 		 * a way to represent this constraint in DRM.
1278 		 */
1279 		regmap_update_bits(tcon->regs, SUN4I_TCON0_CTL_REG,
1280 				   SUN4I_TCON0_CTL_SRC_SEL_MASK,
1281 				   tcon->id);
1282 		regmap_update_bits(tcon->regs, SUN4I_TCON1_CTL_REG,
1283 				   SUN4I_TCON1_CTL_SRC_SEL_MASK,
1284 				   tcon->id);
1285 	}
1286 
1287 	list_add_tail(&tcon->list, &drv->tcon_list);
1288 
1289 	return 0;
1290 
1291 err_free_dotclock:
1292 	if (tcon->quirks->has_channel_0)
1293 		sun4i_dclk_free(tcon);
1294 err_free_clocks:
1295 	sun4i_tcon_free_clocks(tcon);
1296 err_assert_reset:
1297 	reset_control_assert(tcon->lcd_rst);
1298 	return ret;
1299 }
1300 
1301 static void sun4i_tcon_unbind(struct device *dev, struct device *master,
1302 			      void *data)
1303 {
1304 	struct sun4i_tcon *tcon = dev_get_drvdata(dev);
1305 
1306 	list_del(&tcon->list);
1307 	if (tcon->quirks->has_channel_0)
1308 		sun4i_dclk_free(tcon);
1309 	sun4i_tcon_free_clocks(tcon);
1310 }
1311 
1312 static const struct component_ops sun4i_tcon_ops = {
1313 	.bind	= sun4i_tcon_bind,
1314 	.unbind	= sun4i_tcon_unbind,
1315 };
1316 
1317 static int sun4i_tcon_probe(struct platform_device *pdev)
1318 {
1319 	struct device_node *node = pdev->dev.of_node;
1320 	const struct sun4i_tcon_quirks *quirks;
1321 	struct drm_bridge *bridge;
1322 	struct drm_panel *panel;
1323 	int ret;
1324 
1325 	quirks = of_device_get_match_data(&pdev->dev);
1326 
1327 	/* panels and bridges are present only on TCONs with channel 0 */
1328 	if (quirks->has_channel_0) {
1329 		ret = drm_of_find_panel_or_bridge(node, 1, 0, &panel, &bridge);
1330 		if (ret == -EPROBE_DEFER)
1331 			return ret;
1332 	}
1333 
1334 	return component_add(&pdev->dev, &sun4i_tcon_ops);
1335 }
1336 
1337 static int sun4i_tcon_remove(struct platform_device *pdev)
1338 {
1339 	component_del(&pdev->dev, &sun4i_tcon_ops);
1340 
1341 	return 0;
1342 }
1343 
1344 /* platform specific TCON muxing callbacks */
1345 static int sun4i_a10_tcon_set_mux(struct sun4i_tcon *tcon,
1346 				  const struct drm_encoder *encoder)
1347 {
1348 	struct sun4i_tcon *tcon0 = sun4i_get_tcon0(encoder->dev);
1349 	u32 shift;
1350 
1351 	if (!tcon0)
1352 		return -EINVAL;
1353 
1354 	switch (encoder->encoder_type) {
1355 	case DRM_MODE_ENCODER_TMDS:
1356 		/* HDMI */
1357 		shift = 8;
1358 		break;
1359 	default:
1360 		return -EINVAL;
1361 	}
1362 
1363 	regmap_update_bits(tcon0->regs, SUN4I_TCON_MUX_CTRL_REG,
1364 			   0x3 << shift, tcon->id << shift);
1365 
1366 	return 0;
1367 }
1368 
1369 static int sun5i_a13_tcon_set_mux(struct sun4i_tcon *tcon,
1370 				  const struct drm_encoder *encoder)
1371 {
1372 	u32 val;
1373 
1374 	if (encoder->encoder_type == DRM_MODE_ENCODER_TVDAC)
1375 		val = 1;
1376 	else
1377 		val = 0;
1378 
1379 	/*
1380 	 * FIXME: Undocumented bits
1381 	 */
1382 	return regmap_write(tcon->regs, SUN4I_TCON_MUX_CTRL_REG, val);
1383 }
1384 
1385 static int sun6i_tcon_set_mux(struct sun4i_tcon *tcon,
1386 			      const struct drm_encoder *encoder)
1387 {
1388 	struct sun4i_tcon *tcon0 = sun4i_get_tcon0(encoder->dev);
1389 	u32 shift;
1390 
1391 	if (!tcon0)
1392 		return -EINVAL;
1393 
1394 	switch (encoder->encoder_type) {
1395 	case DRM_MODE_ENCODER_TMDS:
1396 		/* HDMI */
1397 		shift = 8;
1398 		break;
1399 	default:
1400 		/* TODO A31 has MIPI DSI but A31s does not */
1401 		return -EINVAL;
1402 	}
1403 
1404 	regmap_update_bits(tcon0->regs, SUN4I_TCON_MUX_CTRL_REG,
1405 			   0x3 << shift, tcon->id << shift);
1406 
1407 	return 0;
1408 }
1409 
1410 static int sun8i_r40_tcon_tv_set_mux(struct sun4i_tcon *tcon,
1411 				     const struct drm_encoder *encoder)
1412 {
1413 	struct device_node *port, *remote;
1414 	struct platform_device *pdev;
1415 	int id, ret;
1416 
1417 	/* find TCON TOP platform device and TCON id */
1418 
1419 	port = of_graph_get_port_by_id(tcon->dev->of_node, 0);
1420 	if (!port)
1421 		return -EINVAL;
1422 
1423 	id = sun4i_tcon_of_get_id_from_port(port);
1424 	of_node_put(port);
1425 
1426 	remote = of_graph_get_remote_node(tcon->dev->of_node, 0, -1);
1427 	if (!remote)
1428 		return -EINVAL;
1429 
1430 	pdev = of_find_device_by_node(remote);
1431 	of_node_put(remote);
1432 	if (!pdev)
1433 		return -EINVAL;
1434 
1435 	if (IS_ENABLED(CONFIG_DRM_SUN8I_TCON_TOP) &&
1436 	    encoder->encoder_type == DRM_MODE_ENCODER_TMDS) {
1437 		ret = sun8i_tcon_top_set_hdmi_src(&pdev->dev, id);
1438 		if (ret)
1439 			return ret;
1440 	}
1441 
1442 	if (IS_ENABLED(CONFIG_DRM_SUN8I_TCON_TOP)) {
1443 		ret = sun8i_tcon_top_de_config(&pdev->dev, tcon->id, id);
1444 		if (ret)
1445 			return ret;
1446 	}
1447 
1448 	return 0;
1449 }
1450 
1451 static const struct sun4i_tcon_quirks sun4i_a10_quirks = {
1452 	.has_channel_0		= true,
1453 	.has_channel_1		= true,
1454 	.dclk_min_div		= 4,
1455 	.set_mux		= sun4i_a10_tcon_set_mux,
1456 };
1457 
1458 static const struct sun4i_tcon_quirks sun5i_a13_quirks = {
1459 	.has_channel_0		= true,
1460 	.has_channel_1		= true,
1461 	.dclk_min_div		= 4,
1462 	.set_mux		= sun5i_a13_tcon_set_mux,
1463 };
1464 
1465 static const struct sun4i_tcon_quirks sun6i_a31_quirks = {
1466 	.has_channel_0		= true,
1467 	.has_channel_1		= true,
1468 	.has_lvds_alt		= true,
1469 	.needs_de_be_mux	= true,
1470 	.dclk_min_div		= 1,
1471 	.set_mux		= sun6i_tcon_set_mux,
1472 };
1473 
1474 static const struct sun4i_tcon_quirks sun6i_a31s_quirks = {
1475 	.has_channel_0		= true,
1476 	.has_channel_1		= true,
1477 	.needs_de_be_mux	= true,
1478 	.dclk_min_div		= 1,
1479 };
1480 
1481 static const struct sun4i_tcon_quirks sun7i_a20_tcon0_quirks = {
1482 	.supports_lvds		= true,
1483 	.has_channel_0		= true,
1484 	.has_channel_1		= true,
1485 	.dclk_min_div		= 4,
1486 	/* Same display pipeline structure as A10 */
1487 	.set_mux		= sun4i_a10_tcon_set_mux,
1488 	.setup_lvds_phy		= sun4i_tcon_setup_lvds_phy,
1489 };
1490 
1491 static const struct sun4i_tcon_quirks sun7i_a20_quirks = {
1492 	.has_channel_0		= true,
1493 	.has_channel_1		= true,
1494 	.dclk_min_div		= 4,
1495 	/* Same display pipeline structure as A10 */
1496 	.set_mux		= sun4i_a10_tcon_set_mux,
1497 };
1498 
1499 static const struct sun4i_tcon_quirks sun8i_a33_quirks = {
1500 	.has_channel_0		= true,
1501 	.has_lvds_alt		= true,
1502 	.dclk_min_div		= 1,
1503 	.setup_lvds_phy		= sun6i_tcon_setup_lvds_phy,
1504 	.supports_lvds		= true,
1505 };
1506 
1507 static const struct sun4i_tcon_quirks sun8i_a83t_lcd_quirks = {
1508 	.supports_lvds		= true,
1509 	.has_channel_0		= true,
1510 	.dclk_min_div		= 1,
1511 	.setup_lvds_phy		= sun6i_tcon_setup_lvds_phy,
1512 };
1513 
1514 static const struct sun4i_tcon_quirks sun8i_a83t_tv_quirks = {
1515 	.has_channel_1		= true,
1516 };
1517 
1518 static const struct sun4i_tcon_quirks sun8i_r40_tv_quirks = {
1519 	.has_channel_1		= true,
1520 	.set_mux		= sun8i_r40_tcon_tv_set_mux,
1521 };
1522 
1523 static const struct sun4i_tcon_quirks sun8i_v3s_quirks = {
1524 	.has_channel_0		= true,
1525 	.dclk_min_div		= 1,
1526 };
1527 
1528 static const struct sun4i_tcon_quirks sun9i_a80_tcon_lcd_quirks = {
1529 	.has_channel_0		= true,
1530 	.needs_edp_reset	= true,
1531 	.dclk_min_div		= 1,
1532 };
1533 
1534 static const struct sun4i_tcon_quirks sun9i_a80_tcon_tv_quirks = {
1535 	.has_channel_1	= true,
1536 	.needs_edp_reset = true,
1537 };
1538 
1539 /* sun4i_drv uses this list to check if a device node is a TCON */
1540 const struct of_device_id sun4i_tcon_of_table[] = {
1541 	{ .compatible = "allwinner,sun4i-a10-tcon", .data = &sun4i_a10_quirks },
1542 	{ .compatible = "allwinner,sun5i-a13-tcon", .data = &sun5i_a13_quirks },
1543 	{ .compatible = "allwinner,sun6i-a31-tcon", .data = &sun6i_a31_quirks },
1544 	{ .compatible = "allwinner,sun6i-a31s-tcon", .data = &sun6i_a31s_quirks },
1545 	{ .compatible = "allwinner,sun7i-a20-tcon", .data = &sun7i_a20_quirks },
1546 	{ .compatible = "allwinner,sun7i-a20-tcon0", .data = &sun7i_a20_tcon0_quirks },
1547 	{ .compatible = "allwinner,sun7i-a20-tcon1", .data = &sun7i_a20_quirks },
1548 	{ .compatible = "allwinner,sun8i-a23-tcon", .data = &sun8i_a33_quirks },
1549 	{ .compatible = "allwinner,sun8i-a33-tcon", .data = &sun8i_a33_quirks },
1550 	{ .compatible = "allwinner,sun8i-a83t-tcon-lcd", .data = &sun8i_a83t_lcd_quirks },
1551 	{ .compatible = "allwinner,sun8i-a83t-tcon-tv", .data = &sun8i_a83t_tv_quirks },
1552 	{ .compatible = "allwinner,sun8i-r40-tcon-tv", .data = &sun8i_r40_tv_quirks },
1553 	{ .compatible = "allwinner,sun8i-v3s-tcon", .data = &sun8i_v3s_quirks },
1554 	{ .compatible = "allwinner,sun9i-a80-tcon-lcd", .data = &sun9i_a80_tcon_lcd_quirks },
1555 	{ .compatible = "allwinner,sun9i-a80-tcon-tv", .data = &sun9i_a80_tcon_tv_quirks },
1556 	{ }
1557 };
1558 MODULE_DEVICE_TABLE(of, sun4i_tcon_of_table);
1559 EXPORT_SYMBOL(sun4i_tcon_of_table);
1560 
1561 static struct platform_driver sun4i_tcon_platform_driver = {
1562 	.probe		= sun4i_tcon_probe,
1563 	.remove		= sun4i_tcon_remove,
1564 	.driver		= {
1565 		.name		= "sun4i-tcon",
1566 		.of_match_table	= sun4i_tcon_of_table,
1567 	},
1568 };
1569 module_platform_driver(sun4i_tcon_platform_driver);
1570 
1571 MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
1572 MODULE_DESCRIPTION("Allwinner A10 Timing Controller Driver");
1573 MODULE_LICENSE("GPL");
1574