xref: /openbmc/linux/drivers/gpu/drm/bridge/tc358767.c (revision 2359ccdd)
1 /*
2  * tc358767 eDP bridge driver
3  *
4  * Copyright (C) 2016 CogentEmbedded Inc
5  * Author: Andrey Gusakov <andrey.gusakov@cogentembedded.com>
6  *
7  * Copyright (C) 2016 Pengutronix, Philipp Zabel <p.zabel@pengutronix.de>
8  *
9  * Copyright (C) 2016 Zodiac Inflight Innovations
10  *
11  * Initially based on: drivers/gpu/drm/i2c/tda998x_drv.c
12  *
13  * Copyright (C) 2012 Texas Instruments
14  * Author: Rob Clark <robdclark@gmail.com>
15  *
16  * This program is free software; you can redistribute it and/or modify
17  * it under the terms of the GNU General Public License as published by
18  * the Free Software Foundation; either version 2 of the License, or
19  * (at your option) any later version.
20  *
21  * This program is distributed in the hope that it will be useful,
22  * but WITHOUT ANY WARRANTY; without even the implied warranty of
23  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
24  * GNU General Public License for more details.
25  */
26 
27 #include <linux/clk.h>
28 #include <linux/device.h>
29 #include <linux/gpio/consumer.h>
30 #include <linux/i2c.h>
31 #include <linux/kernel.h>
32 #include <linux/module.h>
33 #include <linux/regmap.h>
34 #include <linux/slab.h>
35 
36 #include <drm/drm_atomic_helper.h>
37 #include <drm/drm_crtc_helper.h>
38 #include <drm/drm_dp_helper.h>
39 #include <drm/drm_edid.h>
40 #include <drm/drm_of.h>
41 #include <drm/drm_panel.h>
42 
43 /* Registers */
44 
45 /* Display Parallel Interface */
46 #define DPIPXLFMT		0x0440
47 #define VS_POL_ACTIVE_LOW		(1 << 10)
48 #define HS_POL_ACTIVE_LOW		(1 << 9)
49 #define DE_POL_ACTIVE_HIGH		(0 << 8)
50 #define SUB_CFG_TYPE_CONFIG1		(0 << 2) /* LSB aligned */
51 #define SUB_CFG_TYPE_CONFIG2		(1 << 2) /* Loosely Packed */
52 #define SUB_CFG_TYPE_CONFIG3		(2 << 2) /* LSB aligned 8-bit */
53 #define DPI_BPP_RGB888			(0 << 0)
54 #define DPI_BPP_RGB666			(1 << 0)
55 #define DPI_BPP_RGB565			(2 << 0)
56 
57 /* Video Path */
58 #define VPCTRL0			0x0450
59 #define OPXLFMT_RGB666			(0 << 8)
60 #define OPXLFMT_RGB888			(1 << 8)
61 #define FRMSYNC_DISABLED		(0 << 4) /* Video Timing Gen Disabled */
62 #define FRMSYNC_ENABLED			(1 << 4) /* Video Timing Gen Enabled */
63 #define MSF_DISABLED			(0 << 0) /* Magic Square FRC disabled */
64 #define MSF_ENABLED			(1 << 0) /* Magic Square FRC enabled */
65 #define HTIM01			0x0454
66 #define HTIM02			0x0458
67 #define VTIM01			0x045c
68 #define VTIM02			0x0460
69 #define VFUEN0			0x0464
70 #define VFUEN				BIT(0)   /* Video Frame Timing Upload */
71 
72 /* System */
73 #define TC_IDREG		0x0500
74 #define SYSCTRL			0x0510
75 #define DP0_AUDSRC_NO_INPUT		(0 << 3)
76 #define DP0_AUDSRC_I2S_RX		(1 << 3)
77 #define DP0_VIDSRC_NO_INPUT		(0 << 0)
78 #define DP0_VIDSRC_DSI_RX		(1 << 0)
79 #define DP0_VIDSRC_DPI_RX		(2 << 0)
80 #define DP0_VIDSRC_COLOR_BAR		(3 << 0)
81 
82 /* Control */
83 #define DP0CTL			0x0600
84 #define VID_MN_GEN			BIT(6)   /* Auto-generate M/N values */
85 #define EF_EN				BIT(5)   /* Enable Enhanced Framing */
86 #define VID_EN				BIT(1)   /* Video transmission enable */
87 #define DP_EN				BIT(0)   /* Enable DPTX function */
88 
89 /* Clocks */
90 #define DP0_VIDMNGEN0		0x0610
91 #define DP0_VIDMNGEN1		0x0614
92 #define DP0_VMNGENSTATUS	0x0618
93 
94 /* Main Channel */
95 #define DP0_SECSAMPLE		0x0640
96 #define DP0_VIDSYNCDELAY	0x0644
97 #define DP0_TOTALVAL		0x0648
98 #define DP0_STARTVAL		0x064c
99 #define DP0_ACTIVEVAL		0x0650
100 #define DP0_SYNCVAL		0x0654
101 #define DP0_MISC		0x0658
102 #define TU_SIZE_RECOMMENDED		(63) /* LSCLK cycles per TU */
103 #define BPC_6				(0 << 5)
104 #define BPC_8				(1 << 5)
105 
106 /* AUX channel */
107 #define DP0_AUXCFG0		0x0660
108 #define DP0_AUXCFG1		0x0664
109 #define AUX_RX_FILTER_EN		BIT(16)
110 
111 #define DP0_AUXADDR		0x0668
112 #define DP0_AUXWDATA(i)		(0x066c + (i) * 4)
113 #define DP0_AUXRDATA(i)		(0x067c + (i) * 4)
114 #define DP0_AUXSTATUS		0x068c
115 #define AUX_STATUS_MASK			0xf0
116 #define AUX_STATUS_SHIFT		4
117 #define AUX_TIMEOUT			BIT(1)
118 #define AUX_BUSY			BIT(0)
119 #define DP0_AUXI2CADR		0x0698
120 
121 /* Link Training */
122 #define DP0_SRCCTRL		0x06a0
123 #define DP0_SRCCTRL_SCRMBLDIS		BIT(13)
124 #define DP0_SRCCTRL_EN810B		BIT(12)
125 #define DP0_SRCCTRL_NOTP		(0 << 8)
126 #define DP0_SRCCTRL_TP1			(1 << 8)
127 #define DP0_SRCCTRL_TP2			(2 << 8)
128 #define DP0_SRCCTRL_LANESKEW		BIT(7)
129 #define DP0_SRCCTRL_SSCG		BIT(3)
130 #define DP0_SRCCTRL_LANES_1		(0 << 2)
131 #define DP0_SRCCTRL_LANES_2		(1 << 2)
132 #define DP0_SRCCTRL_BW27		(1 << 1)
133 #define DP0_SRCCTRL_BW162		(0 << 1)
134 #define DP0_SRCCTRL_AUTOCORRECT		BIT(0)
135 #define DP0_LTSTAT		0x06d0
136 #define LT_LOOPDONE			BIT(13)
137 #define LT_STATUS_MASK			(0x1f << 8)
138 #define LT_CHANNEL1_EQ_BITS		(DP_CHANNEL_EQ_BITS << 4)
139 #define LT_INTERLANE_ALIGN_DONE		BIT(3)
140 #define LT_CHANNEL0_EQ_BITS		(DP_CHANNEL_EQ_BITS)
141 #define DP0_SNKLTCHGREQ		0x06d4
142 #define DP0_LTLOOPCTRL		0x06d8
143 #define DP0_SNKLTCTRL		0x06e4
144 
145 /* PHY */
146 #define DP_PHY_CTRL		0x0800
147 #define DP_PHY_RST			BIT(28)  /* DP PHY Global Soft Reset */
148 #define BGREN				BIT(25)  /* AUX PHY BGR Enable */
149 #define PWR_SW_EN			BIT(24)  /* PHY Power Switch Enable */
150 #define PHY_M1_RST			BIT(12)  /* Reset PHY1 Main Channel */
151 #define PHY_RDY				BIT(16)  /* PHY Main Channels Ready */
152 #define PHY_M0_RST			BIT(8)   /* Reset PHY0 Main Channel */
153 #define PHY_A0_EN			BIT(1)   /* PHY Aux Channel0 Enable */
154 #define PHY_M0_EN			BIT(0)   /* PHY Main Channel0 Enable */
155 
156 /* PLL */
157 #define DP0_PLLCTRL		0x0900
158 #define DP1_PLLCTRL		0x0904	/* not defined in DS */
159 #define PXL_PLLCTRL		0x0908
160 #define PLLUPDATE			BIT(2)
161 #define PLLBYP				BIT(1)
162 #define PLLEN				BIT(0)
163 #define PXL_PLLPARAM		0x0914
164 #define IN_SEL_REFCLK			(0 << 14)
165 #define SYS_PLLPARAM		0x0918
166 #define REF_FREQ_38M4			(0 << 8) /* 38.4 MHz */
167 #define REF_FREQ_19M2			(1 << 8) /* 19.2 MHz */
168 #define REF_FREQ_26M			(2 << 8) /* 26 MHz */
169 #define REF_FREQ_13M			(3 << 8) /* 13 MHz */
170 #define SYSCLK_SEL_LSCLK		(0 << 4)
171 #define LSCLK_DIV_1			(0 << 0)
172 #define LSCLK_DIV_2			(1 << 0)
173 
174 /* Test & Debug */
175 #define TSTCTL			0x0a00
176 #define PLL_DBG			0x0a04
177 
178 static bool tc_test_pattern;
179 module_param_named(test, tc_test_pattern, bool, 0644);
180 
181 struct tc_edp_link {
182 	struct drm_dp_link	base;
183 	u8			assr;
184 	int			scrambler_dis;
185 	int			spread;
186 	int			coding8b10b;
187 	u8			swing;
188 	u8			preemp;
189 };
190 
191 struct tc_data {
192 	struct device		*dev;
193 	struct regmap		*regmap;
194 	struct drm_dp_aux	aux;
195 
196 	struct drm_bridge	bridge;
197 	struct drm_connector	connector;
198 	struct drm_panel	*panel;
199 
200 	/* link settings */
201 	struct tc_edp_link	link;
202 
203 	/* display edid */
204 	struct edid		*edid;
205 	/* current mode */
206 	struct drm_display_mode	*mode;
207 
208 	u32			rev;
209 	u8			assr;
210 
211 	struct gpio_desc	*sd_gpio;
212 	struct gpio_desc	*reset_gpio;
213 	struct clk		*refclk;
214 };
215 
216 static inline struct tc_data *aux_to_tc(struct drm_dp_aux *a)
217 {
218 	return container_of(a, struct tc_data, aux);
219 }
220 
221 static inline struct tc_data *bridge_to_tc(struct drm_bridge *b)
222 {
223 	return container_of(b, struct tc_data, bridge);
224 }
225 
226 static inline struct tc_data *connector_to_tc(struct drm_connector *c)
227 {
228 	return container_of(c, struct tc_data, connector);
229 }
230 
231 /* Simple macros to avoid repeated error checks */
232 #define tc_write(reg, var)					\
233 	do {							\
234 		ret = regmap_write(tc->regmap, reg, var);	\
235 		if (ret)					\
236 			goto err;				\
237 	} while (0)
238 #define tc_read(reg, var)					\
239 	do {							\
240 		ret = regmap_read(tc->regmap, reg, var);	\
241 		if (ret)					\
242 			goto err;				\
243 	} while (0)
244 
245 static inline int tc_poll_timeout(struct regmap *map, unsigned int addr,
246 				  unsigned int cond_mask,
247 				  unsigned int cond_value,
248 				  unsigned long sleep_us, u64 timeout_us)
249 {
250 	ktime_t timeout = ktime_add_us(ktime_get(), timeout_us);
251 	unsigned int val;
252 	int ret;
253 
254 	for (;;) {
255 		ret = regmap_read(map, addr, &val);
256 		if (ret)
257 			break;
258 		if ((val & cond_mask) == cond_value)
259 			break;
260 		if (timeout_us && ktime_compare(ktime_get(), timeout) > 0) {
261 			ret = regmap_read(map, addr, &val);
262 			break;
263 		}
264 		if (sleep_us)
265 			usleep_range((sleep_us >> 2) + 1, sleep_us);
266 	}
267 	return ret ?: (((val & cond_mask) == cond_value) ? 0 : -ETIMEDOUT);
268 }
269 
270 static int tc_aux_wait_busy(struct tc_data *tc, unsigned int timeout_ms)
271 {
272 	return tc_poll_timeout(tc->regmap, DP0_AUXSTATUS, AUX_BUSY, 0,
273 			       1000, 1000 * timeout_ms);
274 }
275 
276 static int tc_aux_get_status(struct tc_data *tc, u8 *reply)
277 {
278 	int ret;
279 	u32 value;
280 
281 	ret = regmap_read(tc->regmap, DP0_AUXSTATUS, &value);
282 	if (ret < 0)
283 		return ret;
284 	if (value & AUX_BUSY) {
285 		if (value & AUX_TIMEOUT) {
286 			dev_err(tc->dev, "i2c access timeout!\n");
287 			return -ETIMEDOUT;
288 		}
289 		return -EBUSY;
290 	}
291 
292 	*reply = (value & AUX_STATUS_MASK) >> AUX_STATUS_SHIFT;
293 	return 0;
294 }
295 
296 static ssize_t tc_aux_transfer(struct drm_dp_aux *aux,
297 			       struct drm_dp_aux_msg *msg)
298 {
299 	struct tc_data *tc = aux_to_tc(aux);
300 	size_t size = min_t(size_t, 8, msg->size);
301 	u8 request = msg->request & ~DP_AUX_I2C_MOT;
302 	u8 *buf = msg->buffer;
303 	u32 tmp = 0;
304 	int i = 0;
305 	int ret;
306 
307 	if (size == 0)
308 		return 0;
309 
310 	ret = tc_aux_wait_busy(tc, 100);
311 	if (ret)
312 		goto err;
313 
314 	if (request == DP_AUX_I2C_WRITE || request == DP_AUX_NATIVE_WRITE) {
315 		/* Store data */
316 		while (i < size) {
317 			if (request == DP_AUX_NATIVE_WRITE)
318 				tmp = tmp | (buf[i] << (8 * (i & 0x3)));
319 			else
320 				tmp = (tmp << 8) | buf[i];
321 			i++;
322 			if (((i % 4) == 0) || (i == size)) {
323 				tc_write(DP0_AUXWDATA((i - 1) >> 2), tmp);
324 				tmp = 0;
325 			}
326 		}
327 	} else if (request != DP_AUX_I2C_READ &&
328 		   request != DP_AUX_NATIVE_READ) {
329 		return -EINVAL;
330 	}
331 
332 	/* Store address */
333 	tc_write(DP0_AUXADDR, msg->address);
334 	/* Start transfer */
335 	tc_write(DP0_AUXCFG0, ((size - 1) << 8) | request);
336 
337 	ret = tc_aux_wait_busy(tc, 100);
338 	if (ret)
339 		goto err;
340 
341 	ret = tc_aux_get_status(tc, &msg->reply);
342 	if (ret)
343 		goto err;
344 
345 	if (request == DP_AUX_I2C_READ || request == DP_AUX_NATIVE_READ) {
346 		/* Read data */
347 		while (i < size) {
348 			if ((i % 4) == 0)
349 				tc_read(DP0_AUXRDATA(i >> 2), &tmp);
350 			buf[i] = tmp & 0xff;
351 			tmp = tmp >> 8;
352 			i++;
353 		}
354 	}
355 
356 	return size;
357 err:
358 	return ret;
359 }
360 
361 static const char * const training_pattern1_errors[] = {
362 	"No errors",
363 	"Aux write error",
364 	"Aux read error",
365 	"Max voltage reached error",
366 	"Loop counter expired error",
367 	"res", "res", "res"
368 };
369 
370 static const char * const training_pattern2_errors[] = {
371 	"No errors",
372 	"Aux write error",
373 	"Aux read error",
374 	"Clock recovery failed error",
375 	"Loop counter expired error",
376 	"res", "res", "res"
377 };
378 
379 static u32 tc_srcctrl(struct tc_data *tc)
380 {
381 	/*
382 	 * No training pattern, skew lane 1 data by two LSCLK cycles with
383 	 * respect to lane 0 data, AutoCorrect Mode = 0
384 	 */
385 	u32 reg = DP0_SRCCTRL_NOTP | DP0_SRCCTRL_LANESKEW;
386 
387 	if (tc->link.scrambler_dis)
388 		reg |= DP0_SRCCTRL_SCRMBLDIS;	/* Scrambler Disabled */
389 	if (tc->link.coding8b10b)
390 		/* Enable 8/10B Encoder (TxData[19:16] not used) */
391 		reg |= DP0_SRCCTRL_EN810B;
392 	if (tc->link.spread)
393 		reg |= DP0_SRCCTRL_SSCG;	/* Spread Spectrum Enable */
394 	if (tc->link.base.num_lanes == 2)
395 		reg |= DP0_SRCCTRL_LANES_2;	/* Two Main Channel Lanes */
396 	if (tc->link.base.rate != 162000)
397 		reg |= DP0_SRCCTRL_BW27;	/* 2.7 Gbps link */
398 	return reg;
399 }
400 
401 static void tc_wait_pll_lock(struct tc_data *tc)
402 {
403 	/* Wait for PLL to lock: up to 2.09 ms, depending on refclk */
404 	usleep_range(3000, 6000);
405 }
406 
407 static int tc_pxl_pll_en(struct tc_data *tc, u32 refclk, u32 pixelclock)
408 {
409 	int ret;
410 	int i_pre, best_pre = 1;
411 	int i_post, best_post = 1;
412 	int div, best_div = 1;
413 	int mul, best_mul = 1;
414 	int delta, best_delta;
415 	int ext_div[] = {1, 2, 3, 5, 7};
416 	int best_pixelclock = 0;
417 	int vco_hi = 0;
418 
419 	dev_dbg(tc->dev, "PLL: requested %d pixelclock, ref %d\n", pixelclock,
420 		refclk);
421 	best_delta = pixelclock;
422 	/* Loop over all possible ext_divs, skipping invalid configurations */
423 	for (i_pre = 0; i_pre < ARRAY_SIZE(ext_div); i_pre++) {
424 		/*
425 		 * refclk / ext_pre_div should be in the 1 to 200 MHz range.
426 		 * We don't allow any refclk > 200 MHz, only check lower bounds.
427 		 */
428 		if (refclk / ext_div[i_pre] < 1000000)
429 			continue;
430 		for (i_post = 0; i_post < ARRAY_SIZE(ext_div); i_post++) {
431 			for (div = 1; div <= 16; div++) {
432 				u32 clk;
433 				u64 tmp;
434 
435 				tmp = pixelclock * ext_div[i_pre] *
436 				      ext_div[i_post] * div;
437 				do_div(tmp, refclk);
438 				mul = tmp;
439 
440 				/* Check limits */
441 				if ((mul < 1) || (mul > 128))
442 					continue;
443 
444 				clk = (refclk / ext_div[i_pre] / div) * mul;
445 				/*
446 				 * refclk * mul / (ext_pre_div * pre_div)
447 				 * should be in the 150 to 650 MHz range
448 				 */
449 				if ((clk > 650000000) || (clk < 150000000))
450 					continue;
451 
452 				clk = clk / ext_div[i_post];
453 				delta = clk - pixelclock;
454 
455 				if (abs(delta) < abs(best_delta)) {
456 					best_pre = i_pre;
457 					best_post = i_post;
458 					best_div = div;
459 					best_mul = mul;
460 					best_delta = delta;
461 					best_pixelclock = clk;
462 				}
463 			}
464 		}
465 	}
466 	if (best_pixelclock == 0) {
467 		dev_err(tc->dev, "Failed to calc clock for %d pixelclock\n",
468 			pixelclock);
469 		return -EINVAL;
470 	}
471 
472 	dev_dbg(tc->dev, "PLL: got %d, delta %d\n", best_pixelclock,
473 		best_delta);
474 	dev_dbg(tc->dev, "PLL: %d / %d / %d * %d / %d\n", refclk,
475 		ext_div[best_pre], best_div, best_mul, ext_div[best_post]);
476 
477 	/* if VCO >= 300 MHz */
478 	if (refclk / ext_div[best_pre] / best_div * best_mul >= 300000000)
479 		vco_hi = 1;
480 	/* see DS */
481 	if (best_div == 16)
482 		best_div = 0;
483 	if (best_mul == 128)
484 		best_mul = 0;
485 
486 	/* Power up PLL and switch to bypass */
487 	tc_write(PXL_PLLCTRL, PLLBYP | PLLEN);
488 
489 	tc_write(PXL_PLLPARAM,
490 		 (vco_hi << 24) |		/* For PLL VCO >= 300 MHz = 1 */
491 		 (ext_div[best_pre] << 20) |	/* External Pre-divider */
492 		 (ext_div[best_post] << 16) |	/* External Post-divider */
493 		 IN_SEL_REFCLK |		/* Use RefClk as PLL input */
494 		 (best_div << 8) |		/* Divider for PLL RefClk */
495 		 (best_mul << 0));		/* Multiplier for PLL */
496 
497 	/* Force PLL parameter update and disable bypass */
498 	tc_write(PXL_PLLCTRL, PLLUPDATE | PLLEN);
499 
500 	tc_wait_pll_lock(tc);
501 
502 	return 0;
503 err:
504 	return ret;
505 }
506 
507 static int tc_pxl_pll_dis(struct tc_data *tc)
508 {
509 	/* Enable PLL bypass, power down PLL */
510 	return regmap_write(tc->regmap, PXL_PLLCTRL, PLLBYP);
511 }
512 
513 static int tc_stream_clock_calc(struct tc_data *tc)
514 {
515 	int ret;
516 	/*
517 	 * If the Stream clock and Link Symbol clock are
518 	 * asynchronous with each other, the value of M changes over
519 	 * time. This way of generating link clock and stream
520 	 * clock is called Asynchronous Clock mode. The value M
521 	 * must change while the value N stays constant. The
522 	 * value of N in this Asynchronous Clock mode must be set
523 	 * to 2^15 or 32,768.
524 	 *
525 	 * LSCLK = 1/10 of high speed link clock
526 	 *
527 	 * f_STRMCLK = M/N * f_LSCLK
528 	 * M/N = f_STRMCLK / f_LSCLK
529 	 *
530 	 */
531 	tc_write(DP0_VIDMNGEN1, 32768);
532 
533 	return 0;
534 err:
535 	return ret;
536 }
537 
538 static int tc_aux_link_setup(struct tc_data *tc)
539 {
540 	unsigned long rate;
541 	u32 value;
542 	int ret;
543 
544 	rate = clk_get_rate(tc->refclk);
545 	switch (rate) {
546 	case 38400000:
547 		value = REF_FREQ_38M4;
548 		break;
549 	case 26000000:
550 		value = REF_FREQ_26M;
551 		break;
552 	case 19200000:
553 		value = REF_FREQ_19M2;
554 		break;
555 	case 13000000:
556 		value = REF_FREQ_13M;
557 		break;
558 	default:
559 		dev_err(tc->dev, "Invalid refclk rate: %lu Hz\n", rate);
560 		return -EINVAL;
561 	}
562 
563 	/* Setup DP-PHY / PLL */
564 	value |= SYSCLK_SEL_LSCLK | LSCLK_DIV_2;
565 	tc_write(SYS_PLLPARAM, value);
566 
567 	tc_write(DP_PHY_CTRL, BGREN | PWR_SW_EN | BIT(2) | PHY_A0_EN);
568 
569 	/*
570 	 * Initially PLLs are in bypass. Force PLL parameter update,
571 	 * disable PLL bypass, enable PLL
572 	 */
573 	tc_write(DP0_PLLCTRL, PLLUPDATE | PLLEN);
574 	tc_wait_pll_lock(tc);
575 
576 	tc_write(DP1_PLLCTRL, PLLUPDATE | PLLEN);
577 	tc_wait_pll_lock(tc);
578 
579 	ret = tc_poll_timeout(tc->regmap, DP_PHY_CTRL, PHY_RDY, PHY_RDY, 1,
580 			      1000);
581 	if (ret == -ETIMEDOUT) {
582 		dev_err(tc->dev, "Timeout waiting for PHY to become ready");
583 		return ret;
584 	} else if (ret)
585 		goto err;
586 
587 	/* Setup AUX link */
588 	tc_write(DP0_AUXCFG1, AUX_RX_FILTER_EN |
589 		 (0x06 << 8) |	/* Aux Bit Period Calculator Threshold */
590 		 (0x3f << 0));	/* Aux Response Timeout Timer */
591 
592 	return 0;
593 err:
594 	dev_err(tc->dev, "tc_aux_link_setup failed: %d\n", ret);
595 	return ret;
596 }
597 
598 static int tc_get_display_props(struct tc_data *tc)
599 {
600 	int ret;
601 	/* temp buffer */
602 	u8 tmp[8];
603 
604 	/* Read DP Rx Link Capability */
605 	ret = drm_dp_link_probe(&tc->aux, &tc->link.base);
606 	if (ret < 0)
607 		goto err_dpcd_read;
608 	if (tc->link.base.rate != 162000 && tc->link.base.rate != 270000) {
609 		dev_dbg(tc->dev, "Falling to 2.7 Gbps rate\n");
610 		tc->link.base.rate = 270000;
611 	}
612 
613 	if (tc->link.base.num_lanes > 2) {
614 		dev_dbg(tc->dev, "Falling to 2 lanes\n");
615 		tc->link.base.num_lanes = 2;
616 	}
617 
618 	ret = drm_dp_dpcd_readb(&tc->aux, DP_MAX_DOWNSPREAD, tmp);
619 	if (ret < 0)
620 		goto err_dpcd_read;
621 	tc->link.spread = tmp[0] & BIT(0); /* 0.5% down spread */
622 
623 	ret = drm_dp_dpcd_readb(&tc->aux, DP_MAIN_LINK_CHANNEL_CODING, tmp);
624 	if (ret < 0)
625 		goto err_dpcd_read;
626 	tc->link.coding8b10b = tmp[0] & BIT(0);
627 	tc->link.scrambler_dis = 0;
628 	/* read assr */
629 	ret = drm_dp_dpcd_readb(&tc->aux, DP_EDP_CONFIGURATION_SET, tmp);
630 	if (ret < 0)
631 		goto err_dpcd_read;
632 	tc->link.assr = tmp[0] & DP_ALTERNATE_SCRAMBLER_RESET_ENABLE;
633 
634 	dev_dbg(tc->dev, "DPCD rev: %d.%d, rate: %s, lanes: %d, framing: %s\n",
635 		tc->link.base.revision >> 4, tc->link.base.revision & 0x0f,
636 		(tc->link.base.rate == 162000) ? "1.62Gbps" : "2.7Gbps",
637 		tc->link.base.num_lanes,
638 		(tc->link.base.capabilities & DP_LINK_CAP_ENHANCED_FRAMING) ?
639 		"enhanced" : "non-enhanced");
640 	dev_dbg(tc->dev, "ANSI 8B/10B: %d\n", tc->link.coding8b10b);
641 	dev_dbg(tc->dev, "Display ASSR: %d, TC358767 ASSR: %d\n",
642 		tc->link.assr, tc->assr);
643 
644 	return 0;
645 
646 err_dpcd_read:
647 	dev_err(tc->dev, "failed to read DPCD: %d\n", ret);
648 	return ret;
649 }
650 
651 static int tc_set_video_mode(struct tc_data *tc, struct drm_display_mode *mode)
652 {
653 	int ret;
654 	int vid_sync_dly;
655 	int max_tu_symbol;
656 
657 	int left_margin = mode->htotal - mode->hsync_end;
658 	int right_margin = mode->hsync_start - mode->hdisplay;
659 	int hsync_len = mode->hsync_end - mode->hsync_start;
660 	int upper_margin = mode->vtotal - mode->vsync_end;
661 	int lower_margin = mode->vsync_start - mode->vdisplay;
662 	int vsync_len = mode->vsync_end - mode->vsync_start;
663 
664 	/*
665 	 * Recommended maximum number of symbols transferred in a transfer unit:
666 	 * DIV_ROUND_UP((input active video bandwidth in bytes) * tu_size,
667 	 *              (output active video bandwidth in bytes))
668 	 * Must be less than tu_size.
669 	 */
670 	max_tu_symbol = TU_SIZE_RECOMMENDED - 1;
671 
672 	dev_dbg(tc->dev, "set mode %dx%d\n",
673 		mode->hdisplay, mode->vdisplay);
674 	dev_dbg(tc->dev, "H margin %d,%d sync %d\n",
675 		left_margin, right_margin, hsync_len);
676 	dev_dbg(tc->dev, "V margin %d,%d sync %d\n",
677 		upper_margin, lower_margin, vsync_len);
678 	dev_dbg(tc->dev, "total: %dx%d\n", mode->htotal, mode->vtotal);
679 
680 
681 	/*
682 	 * LCD Ctl Frame Size
683 	 * datasheet is not clear of vsdelay in case of DPI
684 	 * assume we do not need any delay when DPI is a source of
685 	 * sync signals
686 	 */
687 	tc_write(VPCTRL0, (0 << 20) /* VSDELAY */ |
688 		 OPXLFMT_RGB888 | FRMSYNC_DISABLED | MSF_DISABLED);
689 	tc_write(HTIM01, (ALIGN(left_margin, 2) << 16) | /* H back porch */
690 			 (ALIGN(hsync_len, 2) << 0));	 /* Hsync */
691 	tc_write(HTIM02, (ALIGN(right_margin, 2) << 16) |  /* H front porch */
692 			 (ALIGN(mode->hdisplay, 2) << 0)); /* width */
693 	tc_write(VTIM01, (upper_margin << 16) |		/* V back porch */
694 			 (vsync_len << 0));		/* Vsync */
695 	tc_write(VTIM02, (lower_margin << 16) |		/* V front porch */
696 			 (mode->vdisplay << 0));	/* height */
697 	tc_write(VFUEN0, VFUEN);		/* update settings */
698 
699 	/* Test pattern settings */
700 	tc_write(TSTCTL,
701 		 (120 << 24) |	/* Red Color component value */
702 		 (20 << 16) |	/* Green Color component value */
703 		 (99 << 8) |	/* Blue Color component value */
704 		 (1 << 4) |	/* Enable I2C Filter */
705 		 (2 << 0) |	/* Color bar Mode */
706 		 0);
707 
708 	/* DP Main Stream Attributes */
709 	vid_sync_dly = hsync_len + left_margin + mode->hdisplay;
710 	tc_write(DP0_VIDSYNCDELAY,
711 		 (max_tu_symbol << 16) |	/* thresh_dly */
712 		 (vid_sync_dly << 0));
713 
714 	tc_write(DP0_TOTALVAL, (mode->vtotal << 16) | (mode->htotal));
715 
716 	tc_write(DP0_STARTVAL,
717 		 ((upper_margin + vsync_len) << 16) |
718 		 ((left_margin + hsync_len) << 0));
719 
720 	tc_write(DP0_ACTIVEVAL, (mode->vdisplay << 16) | (mode->hdisplay));
721 
722 	tc_write(DP0_SYNCVAL, (vsync_len << 16) | (hsync_len << 0));
723 
724 	tc_write(DPIPXLFMT, VS_POL_ACTIVE_LOW | HS_POL_ACTIVE_LOW |
725 		 DE_POL_ACTIVE_HIGH | SUB_CFG_TYPE_CONFIG1 | DPI_BPP_RGB888);
726 
727 	tc_write(DP0_MISC, (max_tu_symbol << 23) | (TU_SIZE_RECOMMENDED << 16) |
728 			   BPC_8);
729 
730 	return 0;
731 err:
732 	return ret;
733 }
734 
735 static int tc_link_training(struct tc_data *tc, int pattern)
736 {
737 	const char * const *errors;
738 	u32 srcctrl = tc_srcctrl(tc) | DP0_SRCCTRL_SCRMBLDIS |
739 		      DP0_SRCCTRL_AUTOCORRECT;
740 	int timeout;
741 	int retry;
742 	u32 value;
743 	int ret;
744 
745 	if (pattern == DP_TRAINING_PATTERN_1) {
746 		srcctrl |= DP0_SRCCTRL_TP1;
747 		errors = training_pattern1_errors;
748 	} else {
749 		srcctrl |= DP0_SRCCTRL_TP2;
750 		errors = training_pattern2_errors;
751 	}
752 
753 	/* Set DPCD 0x102 for Training Part 1 or 2 */
754 	tc_write(DP0_SNKLTCTRL, DP_LINK_SCRAMBLING_DISABLE | pattern);
755 
756 	tc_write(DP0_LTLOOPCTRL,
757 		 (0x0f << 28) |	/* Defer Iteration Count */
758 		 (0x0f << 24) |	/* Loop Iteration Count */
759 		 (0x0d << 0));	/* Loop Timer Delay */
760 
761 	retry = 5;
762 	do {
763 		/* Set DP0 Training Pattern */
764 		tc_write(DP0_SRCCTRL, srcctrl);
765 
766 		/* Enable DP0 to start Link Training */
767 		tc_write(DP0CTL, DP_EN);
768 
769 		/* wait */
770 		timeout = 1000;
771 		do {
772 			tc_read(DP0_LTSTAT, &value);
773 			udelay(1);
774 		} while ((!(value & LT_LOOPDONE)) && (--timeout));
775 		if (timeout == 0) {
776 			dev_err(tc->dev, "Link training timeout!\n");
777 		} else {
778 			int pattern = (value >> 11) & 0x3;
779 			int error = (value >> 8) & 0x7;
780 
781 			dev_dbg(tc->dev,
782 				"Link training phase %d done after %d uS: %s\n",
783 				pattern, 1000 - timeout, errors[error]);
784 			if (pattern == DP_TRAINING_PATTERN_1 && error == 0)
785 				break;
786 			if (pattern == DP_TRAINING_PATTERN_2) {
787 				value &= LT_CHANNEL1_EQ_BITS |
788 					 LT_INTERLANE_ALIGN_DONE |
789 					 LT_CHANNEL0_EQ_BITS;
790 				/* in case of two lanes */
791 				if ((tc->link.base.num_lanes == 2) &&
792 				    (value == (LT_CHANNEL1_EQ_BITS |
793 					       LT_INTERLANE_ALIGN_DONE |
794 					       LT_CHANNEL0_EQ_BITS)))
795 					break;
796 				/* in case of one line */
797 				if ((tc->link.base.num_lanes == 1) &&
798 				    (value == (LT_INTERLANE_ALIGN_DONE |
799 					       LT_CHANNEL0_EQ_BITS)))
800 					break;
801 			}
802 		}
803 		/* restart */
804 		tc_write(DP0CTL, 0);
805 		usleep_range(10, 20);
806 	} while (--retry);
807 	if (retry == 0) {
808 		dev_err(tc->dev, "Failed to finish training phase %d\n",
809 			pattern);
810 	}
811 
812 	return 0;
813 err:
814 	return ret;
815 }
816 
817 static int tc_main_link_setup(struct tc_data *tc)
818 {
819 	struct drm_dp_aux *aux = &tc->aux;
820 	struct device *dev = tc->dev;
821 	unsigned int rate;
822 	u32 dp_phy_ctrl;
823 	int timeout;
824 	u32 value;
825 	int ret;
826 	u8 tmp[8];
827 
828 	/* display mode should be set at this point */
829 	if (!tc->mode)
830 		return -EINVAL;
831 
832 	/* from excel file - DP0_SrcCtrl */
833 	tc_write(DP0_SRCCTRL, DP0_SRCCTRL_SCRMBLDIS | DP0_SRCCTRL_EN810B |
834 		 DP0_SRCCTRL_LANESKEW | DP0_SRCCTRL_LANES_2 |
835 		 DP0_SRCCTRL_BW27 | DP0_SRCCTRL_AUTOCORRECT);
836 	/* from excel file - DP1_SrcCtrl */
837 	tc_write(0x07a0, 0x00003083);
838 
839 	rate = clk_get_rate(tc->refclk);
840 	switch (rate) {
841 	case 38400000:
842 		value = REF_FREQ_38M4;
843 		break;
844 	case 26000000:
845 		value = REF_FREQ_26M;
846 		break;
847 	case 19200000:
848 		value = REF_FREQ_19M2;
849 		break;
850 	case 13000000:
851 		value = REF_FREQ_13M;
852 		break;
853 	default:
854 		return -EINVAL;
855 	}
856 	value |= SYSCLK_SEL_LSCLK | LSCLK_DIV_2;
857 	tc_write(SYS_PLLPARAM, value);
858 	/* Setup Main Link */
859 	dp_phy_ctrl = BGREN | PWR_SW_EN | BIT(2) | PHY_A0_EN |  PHY_M0_EN;
860 	tc_write(DP_PHY_CTRL, dp_phy_ctrl);
861 	msleep(100);
862 
863 	/* PLL setup */
864 	tc_write(DP0_PLLCTRL, PLLUPDATE | PLLEN);
865 	tc_wait_pll_lock(tc);
866 
867 	tc_write(DP1_PLLCTRL, PLLUPDATE | PLLEN);
868 	tc_wait_pll_lock(tc);
869 
870 	/* PXL PLL setup */
871 	if (tc_test_pattern) {
872 		ret = tc_pxl_pll_en(tc, clk_get_rate(tc->refclk),
873 				    1000 * tc->mode->clock);
874 		if (ret)
875 			goto err;
876 	}
877 
878 	/* Reset/Enable Main Links */
879 	dp_phy_ctrl |= DP_PHY_RST | PHY_M1_RST | PHY_M0_RST;
880 	tc_write(DP_PHY_CTRL, dp_phy_ctrl);
881 	usleep_range(100, 200);
882 	dp_phy_ctrl &= ~(DP_PHY_RST | PHY_M1_RST | PHY_M0_RST);
883 	tc_write(DP_PHY_CTRL, dp_phy_ctrl);
884 
885 	timeout = 1000;
886 	do {
887 		tc_read(DP_PHY_CTRL, &value);
888 		udelay(1);
889 	} while ((!(value & PHY_RDY)) && (--timeout));
890 
891 	if (timeout == 0) {
892 		dev_err(dev, "timeout waiting for phy become ready");
893 		return -ETIMEDOUT;
894 	}
895 
896 	/* Set misc: 8 bits per color */
897 	ret = regmap_update_bits(tc->regmap, DP0_MISC, BPC_8, BPC_8);
898 	if (ret)
899 		goto err;
900 
901 	/*
902 	 * ASSR mode
903 	 * on TC358767 side ASSR configured through strap pin
904 	 * seems there is no way to change this setting from SW
905 	 *
906 	 * check is tc configured for same mode
907 	 */
908 	if (tc->assr != tc->link.assr) {
909 		dev_dbg(dev, "Trying to set display to ASSR: %d\n",
910 			tc->assr);
911 		/* try to set ASSR on display side */
912 		tmp[0] = tc->assr;
913 		ret = drm_dp_dpcd_writeb(aux, DP_EDP_CONFIGURATION_SET, tmp[0]);
914 		if (ret < 0)
915 			goto err_dpcd_read;
916 		/* read back */
917 		ret = drm_dp_dpcd_readb(aux, DP_EDP_CONFIGURATION_SET, tmp);
918 		if (ret < 0)
919 			goto err_dpcd_read;
920 
921 		if (tmp[0] != tc->assr) {
922 			dev_dbg(dev, "Failed to switch display ASSR to %d, falling back to unscrambled mode\n",
923 				 tc->assr);
924 			/* trying with disabled scrambler */
925 			tc->link.scrambler_dis = 1;
926 		}
927 	}
928 
929 	/* Setup Link & DPRx Config for Training */
930 	ret = drm_dp_link_configure(aux, &tc->link.base);
931 	if (ret < 0)
932 		goto err_dpcd_write;
933 
934 	/* DOWNSPREAD_CTRL */
935 	tmp[0] = tc->link.spread ? DP_SPREAD_AMP_0_5 : 0x00;
936 	/* MAIN_LINK_CHANNEL_CODING_SET */
937 	tmp[1] =  tc->link.coding8b10b ? DP_SET_ANSI_8B10B : 0x00;
938 	ret = drm_dp_dpcd_write(aux, DP_DOWNSPREAD_CTRL, tmp, 2);
939 	if (ret < 0)
940 		goto err_dpcd_write;
941 
942 	ret = tc_link_training(tc, DP_TRAINING_PATTERN_1);
943 	if (ret)
944 		goto err;
945 
946 	ret = tc_link_training(tc, DP_TRAINING_PATTERN_2);
947 	if (ret)
948 		goto err;
949 
950 	/* Clear DPCD 0x102 */
951 	/* Note: Can Not use DP0_SNKLTCTRL (0x06E4) short cut */
952 	tmp[0] = tc->link.scrambler_dis ? DP_LINK_SCRAMBLING_DISABLE : 0x00;
953 	ret = drm_dp_dpcd_writeb(aux, DP_TRAINING_PATTERN_SET, tmp[0]);
954 	if (ret < 0)
955 		goto err_dpcd_write;
956 
957 	/* Clear Training Pattern, set AutoCorrect Mode = 1 */
958 	tc_write(DP0_SRCCTRL, tc_srcctrl(tc) | DP0_SRCCTRL_AUTOCORRECT);
959 
960 	/* Wait */
961 	timeout = 100;
962 	do {
963 		udelay(1);
964 		/* Read DPCD 0x202-0x207 */
965 		ret = drm_dp_dpcd_read_link_status(aux, tmp + 2);
966 		if (ret < 0)
967 			goto err_dpcd_read;
968 	} while ((--timeout) &&
969 		 !(drm_dp_channel_eq_ok(tmp + 2,  tc->link.base.num_lanes)));
970 
971 	if (timeout == 0) {
972 		/* Read DPCD 0x200-0x201 */
973 		ret = drm_dp_dpcd_read(aux, DP_SINK_COUNT, tmp, 2);
974 		if (ret < 0)
975 			goto err_dpcd_read;
976 		dev_err(dev, "channel(s) EQ not ok\n");
977 		dev_info(dev, "0x0200 SINK_COUNT: 0x%02x\n", tmp[0]);
978 		dev_info(dev, "0x0201 DEVICE_SERVICE_IRQ_VECTOR: 0x%02x\n",
979 			 tmp[1]);
980 		dev_info(dev, "0x0202 LANE0_1_STATUS: 0x%02x\n", tmp[2]);
981 		dev_info(dev, "0x0204 LANE_ALIGN_STATUS_UPDATED: 0x%02x\n",
982 			 tmp[4]);
983 		dev_info(dev, "0x0205 SINK_STATUS: 0x%02x\n", tmp[5]);
984 		dev_info(dev, "0x0206 ADJUST_REQUEST_LANE0_1: 0x%02x\n",
985 			 tmp[6]);
986 
987 		return -EAGAIN;
988 	}
989 
990 	ret = tc_set_video_mode(tc, tc->mode);
991 	if (ret)
992 		goto err;
993 
994 	/* Set M/N */
995 	ret = tc_stream_clock_calc(tc);
996 	if (ret)
997 		goto err;
998 
999 	return 0;
1000 err_dpcd_read:
1001 	dev_err(tc->dev, "Failed to read DPCD: %d\n", ret);
1002 	return ret;
1003 err_dpcd_write:
1004 	dev_err(tc->dev, "Failed to write DPCD: %d\n", ret);
1005 err:
1006 	return ret;
1007 }
1008 
1009 static int tc_main_link_stream(struct tc_data *tc, int state)
1010 {
1011 	int ret;
1012 	u32 value;
1013 
1014 	dev_dbg(tc->dev, "stream: %d\n", state);
1015 
1016 	if (state) {
1017 		value = VID_MN_GEN | DP_EN;
1018 		if (tc->link.base.capabilities & DP_LINK_CAP_ENHANCED_FRAMING)
1019 			value |= EF_EN;
1020 		tc_write(DP0CTL, value);
1021 		/*
1022 		 * VID_EN assertion should be delayed by at least N * LSCLK
1023 		 * cycles from the time VID_MN_GEN is enabled in order to
1024 		 * generate stable values for VID_M. LSCLK is 270 MHz or
1025 		 * 162 MHz, VID_N is set to 32768 in  tc_stream_clock_calc(),
1026 		 * so a delay of at least 203 us should suffice.
1027 		 */
1028 		usleep_range(500, 1000);
1029 		value |= VID_EN;
1030 		tc_write(DP0CTL, value);
1031 		/* Set input interface */
1032 		value = DP0_AUDSRC_NO_INPUT;
1033 		if (tc_test_pattern)
1034 			value |= DP0_VIDSRC_COLOR_BAR;
1035 		else
1036 			value |= DP0_VIDSRC_DPI_RX;
1037 		tc_write(SYSCTRL, value);
1038 	} else {
1039 		tc_write(DP0CTL, 0);
1040 	}
1041 
1042 	return 0;
1043 err:
1044 	return ret;
1045 }
1046 
1047 static void tc_bridge_pre_enable(struct drm_bridge *bridge)
1048 {
1049 	struct tc_data *tc = bridge_to_tc(bridge);
1050 
1051 	drm_panel_prepare(tc->panel);
1052 }
1053 
1054 static void tc_bridge_enable(struct drm_bridge *bridge)
1055 {
1056 	struct tc_data *tc = bridge_to_tc(bridge);
1057 	int ret;
1058 
1059 	ret = tc_main_link_setup(tc);
1060 	if (ret < 0) {
1061 		dev_err(tc->dev, "main link setup error: %d\n", ret);
1062 		return;
1063 	}
1064 
1065 	ret = tc_main_link_stream(tc, 1);
1066 	if (ret < 0) {
1067 		dev_err(tc->dev, "main link stream start error: %d\n", ret);
1068 		return;
1069 	}
1070 
1071 	drm_panel_enable(tc->panel);
1072 }
1073 
1074 static void tc_bridge_disable(struct drm_bridge *bridge)
1075 {
1076 	struct tc_data *tc = bridge_to_tc(bridge);
1077 	int ret;
1078 
1079 	drm_panel_disable(tc->panel);
1080 
1081 	ret = tc_main_link_stream(tc, 0);
1082 	if (ret < 0)
1083 		dev_err(tc->dev, "main link stream stop error: %d\n", ret);
1084 }
1085 
1086 static void tc_bridge_post_disable(struct drm_bridge *bridge)
1087 {
1088 	struct tc_data *tc = bridge_to_tc(bridge);
1089 
1090 	drm_panel_unprepare(tc->panel);
1091 }
1092 
1093 static bool tc_bridge_mode_fixup(struct drm_bridge *bridge,
1094 				 const struct drm_display_mode *mode,
1095 				 struct drm_display_mode *adj)
1096 {
1097 	/* Fixup sync polarities, both hsync and vsync are active low */
1098 	adj->flags = mode->flags;
1099 	adj->flags |= (DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC);
1100 	adj->flags &= ~(DRM_MODE_FLAG_PHSYNC | DRM_MODE_FLAG_PVSYNC);
1101 
1102 	return true;
1103 }
1104 
1105 static int tc_connector_mode_valid(struct drm_connector *connector,
1106 				   struct drm_display_mode *mode)
1107 {
1108 	/* DPI interface clock limitation: upto 154 MHz */
1109 	if (mode->clock > 154000)
1110 		return MODE_CLOCK_HIGH;
1111 
1112 	return MODE_OK;
1113 }
1114 
1115 static void tc_bridge_mode_set(struct drm_bridge *bridge,
1116 			       struct drm_display_mode *mode,
1117 			       struct drm_display_mode *adj)
1118 {
1119 	struct tc_data *tc = bridge_to_tc(bridge);
1120 
1121 	tc->mode = mode;
1122 }
1123 
1124 static int tc_connector_get_modes(struct drm_connector *connector)
1125 {
1126 	struct tc_data *tc = connector_to_tc(connector);
1127 	struct edid *edid;
1128 	unsigned int count;
1129 
1130 	if (tc->panel && tc->panel->funcs && tc->panel->funcs->get_modes) {
1131 		count = tc->panel->funcs->get_modes(tc->panel);
1132 		if (count > 0)
1133 			return count;
1134 	}
1135 
1136 	edid = drm_get_edid(connector, &tc->aux.ddc);
1137 
1138 	kfree(tc->edid);
1139 	tc->edid = edid;
1140 	if (!edid)
1141 		return 0;
1142 
1143 	drm_mode_connector_update_edid_property(connector, edid);
1144 	count = drm_add_edid_modes(connector, edid);
1145 
1146 	return count;
1147 }
1148 
1149 static void tc_connector_set_polling(struct tc_data *tc,
1150 				     struct drm_connector *connector)
1151 {
1152 	/* TODO: add support for HPD */
1153 	connector->polled = DRM_CONNECTOR_POLL_CONNECT |
1154 			    DRM_CONNECTOR_POLL_DISCONNECT;
1155 }
1156 
1157 static struct drm_encoder *
1158 tc_connector_best_encoder(struct drm_connector *connector)
1159 {
1160 	struct tc_data *tc = connector_to_tc(connector);
1161 
1162 	return tc->bridge.encoder;
1163 }
1164 
1165 static const struct drm_connector_helper_funcs tc_connector_helper_funcs = {
1166 	.get_modes = tc_connector_get_modes,
1167 	.mode_valid = tc_connector_mode_valid,
1168 	.best_encoder = tc_connector_best_encoder,
1169 };
1170 
1171 static const struct drm_connector_funcs tc_connector_funcs = {
1172 	.fill_modes = drm_helper_probe_single_connector_modes,
1173 	.destroy = drm_connector_cleanup,
1174 	.reset = drm_atomic_helper_connector_reset,
1175 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
1176 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
1177 };
1178 
1179 static int tc_bridge_attach(struct drm_bridge *bridge)
1180 {
1181 	u32 bus_format = MEDIA_BUS_FMT_RGB888_1X24;
1182 	struct tc_data *tc = bridge_to_tc(bridge);
1183 	struct drm_device *drm = bridge->dev;
1184 	int ret;
1185 
1186 	/* Create eDP connector */
1187 	drm_connector_helper_add(&tc->connector, &tc_connector_helper_funcs);
1188 	ret = drm_connector_init(drm, &tc->connector, &tc_connector_funcs,
1189 				 DRM_MODE_CONNECTOR_eDP);
1190 	if (ret)
1191 		return ret;
1192 
1193 	if (tc->panel)
1194 		drm_panel_attach(tc->panel, &tc->connector);
1195 
1196 	drm_display_info_set_bus_formats(&tc->connector.display_info,
1197 					 &bus_format, 1);
1198 	drm_mode_connector_attach_encoder(&tc->connector, tc->bridge.encoder);
1199 
1200 	return 0;
1201 }
1202 
1203 static const struct drm_bridge_funcs tc_bridge_funcs = {
1204 	.attach = tc_bridge_attach,
1205 	.mode_set = tc_bridge_mode_set,
1206 	.pre_enable = tc_bridge_pre_enable,
1207 	.enable = tc_bridge_enable,
1208 	.disable = tc_bridge_disable,
1209 	.post_disable = tc_bridge_post_disable,
1210 	.mode_fixup = tc_bridge_mode_fixup,
1211 };
1212 
1213 static bool tc_readable_reg(struct device *dev, unsigned int reg)
1214 {
1215 	return reg != SYSCTRL;
1216 }
1217 
1218 static const struct regmap_range tc_volatile_ranges[] = {
1219 	regmap_reg_range(DP0_AUXWDATA(0), DP0_AUXSTATUS),
1220 	regmap_reg_range(DP0_LTSTAT, DP0_SNKLTCHGREQ),
1221 	regmap_reg_range(DP_PHY_CTRL, DP_PHY_CTRL),
1222 	regmap_reg_range(DP0_PLLCTRL, PXL_PLLCTRL),
1223 	regmap_reg_range(VFUEN0, VFUEN0),
1224 };
1225 
1226 static const struct regmap_access_table tc_volatile_table = {
1227 	.yes_ranges = tc_volatile_ranges,
1228 	.n_yes_ranges = ARRAY_SIZE(tc_volatile_ranges),
1229 };
1230 
1231 static bool tc_writeable_reg(struct device *dev, unsigned int reg)
1232 {
1233 	return (reg != TC_IDREG) &&
1234 	       (reg != DP0_LTSTAT) &&
1235 	       (reg != DP0_SNKLTCHGREQ);
1236 }
1237 
1238 static const struct regmap_config tc_regmap_config = {
1239 	.name = "tc358767",
1240 	.reg_bits = 16,
1241 	.val_bits = 32,
1242 	.reg_stride = 4,
1243 	.max_register = PLL_DBG,
1244 	.cache_type = REGCACHE_RBTREE,
1245 	.readable_reg = tc_readable_reg,
1246 	.volatile_table = &tc_volatile_table,
1247 	.writeable_reg = tc_writeable_reg,
1248 	.reg_format_endian = REGMAP_ENDIAN_BIG,
1249 	.val_format_endian = REGMAP_ENDIAN_LITTLE,
1250 };
1251 
1252 static int tc_probe(struct i2c_client *client, const struct i2c_device_id *id)
1253 {
1254 	struct device *dev = &client->dev;
1255 	struct tc_data *tc;
1256 	int ret;
1257 
1258 	tc = devm_kzalloc(dev, sizeof(*tc), GFP_KERNEL);
1259 	if (!tc)
1260 		return -ENOMEM;
1261 
1262 	tc->dev = dev;
1263 
1264 	/* port@2 is the output port */
1265 	ret = drm_of_find_panel_or_bridge(dev->of_node, 2, 0, &tc->panel, NULL);
1266 	if (ret && ret != -ENODEV)
1267 		return ret;
1268 
1269 	/* Shut down GPIO is optional */
1270 	tc->sd_gpio = devm_gpiod_get_optional(dev, "shutdown", GPIOD_OUT_HIGH);
1271 	if (IS_ERR(tc->sd_gpio))
1272 		return PTR_ERR(tc->sd_gpio);
1273 
1274 	if (tc->sd_gpio) {
1275 		gpiod_set_value_cansleep(tc->sd_gpio, 0);
1276 		usleep_range(5000, 10000);
1277 	}
1278 
1279 	/* Reset GPIO is optional */
1280 	tc->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
1281 	if (IS_ERR(tc->reset_gpio))
1282 		return PTR_ERR(tc->reset_gpio);
1283 
1284 	if (tc->reset_gpio) {
1285 		gpiod_set_value_cansleep(tc->reset_gpio, 1);
1286 		usleep_range(5000, 10000);
1287 	}
1288 
1289 	tc->refclk = devm_clk_get(dev, "ref");
1290 	if (IS_ERR(tc->refclk)) {
1291 		ret = PTR_ERR(tc->refclk);
1292 		dev_err(dev, "Failed to get refclk: %d\n", ret);
1293 		return ret;
1294 	}
1295 
1296 	tc->regmap = devm_regmap_init_i2c(client, &tc_regmap_config);
1297 	if (IS_ERR(tc->regmap)) {
1298 		ret = PTR_ERR(tc->regmap);
1299 		dev_err(dev, "Failed to initialize regmap: %d\n", ret);
1300 		return ret;
1301 	}
1302 
1303 	ret = regmap_read(tc->regmap, TC_IDREG, &tc->rev);
1304 	if (ret) {
1305 		dev_err(tc->dev, "can not read device ID: %d\n", ret);
1306 		return ret;
1307 	}
1308 
1309 	if ((tc->rev != 0x6601) && (tc->rev != 0x6603)) {
1310 		dev_err(tc->dev, "invalid device ID: 0x%08x\n", tc->rev);
1311 		return -EINVAL;
1312 	}
1313 
1314 	tc->assr = (tc->rev == 0x6601); /* Enable ASSR for eDP panels */
1315 
1316 	ret = tc_aux_link_setup(tc);
1317 	if (ret)
1318 		return ret;
1319 
1320 	/* Register DP AUX channel */
1321 	tc->aux.name = "TC358767 AUX i2c adapter";
1322 	tc->aux.dev = tc->dev;
1323 	tc->aux.transfer = tc_aux_transfer;
1324 	ret = drm_dp_aux_register(&tc->aux);
1325 	if (ret)
1326 		return ret;
1327 
1328 	ret = tc_get_display_props(tc);
1329 	if (ret)
1330 		goto err_unregister_aux;
1331 
1332 	tc_connector_set_polling(tc, &tc->connector);
1333 
1334 	tc->bridge.funcs = &tc_bridge_funcs;
1335 	tc->bridge.of_node = dev->of_node;
1336 	drm_bridge_add(&tc->bridge);
1337 
1338 	i2c_set_clientdata(client, tc);
1339 
1340 	return 0;
1341 err_unregister_aux:
1342 	drm_dp_aux_unregister(&tc->aux);
1343 	return ret;
1344 }
1345 
1346 static int tc_remove(struct i2c_client *client)
1347 {
1348 	struct tc_data *tc = i2c_get_clientdata(client);
1349 
1350 	drm_bridge_remove(&tc->bridge);
1351 	drm_dp_aux_unregister(&tc->aux);
1352 
1353 	tc_pxl_pll_dis(tc);
1354 
1355 	return 0;
1356 }
1357 
1358 static const struct i2c_device_id tc358767_i2c_ids[] = {
1359 	{ "tc358767", 0 },
1360 	{ }
1361 };
1362 MODULE_DEVICE_TABLE(i2c, tc358767_i2c_ids);
1363 
1364 static const struct of_device_id tc358767_of_ids[] = {
1365 	{ .compatible = "toshiba,tc358767", },
1366 	{ }
1367 };
1368 MODULE_DEVICE_TABLE(of, tc358767_of_ids);
1369 
1370 static struct i2c_driver tc358767_driver = {
1371 	.driver = {
1372 		.name = "tc358767",
1373 		.of_match_table = tc358767_of_ids,
1374 	},
1375 	.id_table = tc358767_i2c_ids,
1376 	.probe = tc_probe,
1377 	.remove	= tc_remove,
1378 };
1379 module_i2c_driver(tc358767_driver);
1380 
1381 MODULE_AUTHOR("Andrey Gusakov <andrey.gusakov@cogentembedded.com>");
1382 MODULE_DESCRIPTION("tc358767 eDP encoder driver");
1383 MODULE_LICENSE("GPL");
1384