xref: /openbmc/linux/drivers/gpu/drm/bridge/tc358767.c (revision 4f6cce39)
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  * Initially based on: drivers/gpu/drm/i2c/tda998x_drv.c
10  *
11  * Copyright (C) 2012 Texas Instruments
12  * Author: Rob Clark <robdclark@gmail.com>
13  *
14  * This program is free software; you can redistribute it and/or modify
15  * it under the terms of the GNU General Public License as published by
16  * the Free Software Foundation; either version 2 of the License, or
17  * (at your option) any later version.
18  *
19  * This program is distributed in the hope that it will be useful,
20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
22  * GNU General Public License for more details.
23  */
24 
25 #include <linux/clk.h>
26 #include <linux/device.h>
27 #include <linux/gpio/consumer.h>
28 #include <linux/i2c.h>
29 #include <linux/kernel.h>
30 #include <linux/module.h>
31 #include <linux/regmap.h>
32 #include <linux/slab.h>
33 
34 #include <drm/drm_atomic_helper.h>
35 #include <drm/drm_crtc_helper.h>
36 #include <drm/drm_dp_helper.h>
37 #include <drm/drm_edid.h>
38 #include <drm/drm_of.h>
39 #include <drm/drm_panel.h>
40 
41 /* Registers */
42 
43 /* Display Parallel Interface */
44 #define DPIPXLFMT		0x0440
45 #define VS_POL_ACTIVE_LOW		(1 << 10)
46 #define HS_POL_ACTIVE_LOW		(1 << 9)
47 #define DE_POL_ACTIVE_HIGH		(0 << 8)
48 #define SUB_CFG_TYPE_CONFIG1		(0 << 2) /* LSB aligned */
49 #define SUB_CFG_TYPE_CONFIG2		(1 << 2) /* Loosely Packed */
50 #define SUB_CFG_TYPE_CONFIG3		(2 << 2) /* LSB aligned 8-bit */
51 #define DPI_BPP_RGB888			(0 << 0)
52 #define DPI_BPP_RGB666			(1 << 0)
53 #define DPI_BPP_RGB565			(2 << 0)
54 
55 /* Video Path */
56 #define VPCTRL0			0x0450
57 #define OPXLFMT_RGB666			(0 << 8)
58 #define OPXLFMT_RGB888			(1 << 8)
59 #define FRMSYNC_DISABLED		(0 << 4) /* Video Timing Gen Disabled */
60 #define FRMSYNC_ENABLED			(1 << 4) /* Video Timing Gen Enabled */
61 #define MSF_DISABLED			(0 << 0) /* Magic Square FRC disabled */
62 #define MSF_ENABLED			(1 << 0) /* Magic Square FRC enabled */
63 #define HTIM01			0x0454
64 #define HTIM02			0x0458
65 #define VTIM01			0x045c
66 #define VTIM02			0x0460
67 #define VFUEN0			0x0464
68 #define VFUEN				BIT(0)   /* Video Frame Timing Upload */
69 
70 /* System */
71 #define TC_IDREG		0x0500
72 #define SYSCTRL			0x0510
73 #define DP0_AUDSRC_NO_INPUT		(0 << 3)
74 #define DP0_AUDSRC_I2S_RX		(1 << 3)
75 #define DP0_VIDSRC_NO_INPUT		(0 << 0)
76 #define DP0_VIDSRC_DSI_RX		(1 << 0)
77 #define DP0_VIDSRC_DPI_RX		(2 << 0)
78 #define DP0_VIDSRC_COLOR_BAR		(3 << 0)
79 
80 /* Control */
81 #define DP0CTL			0x0600
82 #define VID_MN_GEN			BIT(6)   /* Auto-generate M/N values */
83 #define EF_EN				BIT(5)   /* Enable Enhanced Framing */
84 #define VID_EN				BIT(1)   /* Video transmission enable */
85 #define DP_EN				BIT(0)   /* Enable DPTX function */
86 
87 /* Clocks */
88 #define DP0_VIDMNGEN0		0x0610
89 #define DP0_VIDMNGEN1		0x0614
90 #define DP0_VMNGENSTATUS	0x0618
91 
92 /* Main Channel */
93 #define DP0_SECSAMPLE		0x0640
94 #define DP0_VIDSYNCDELAY	0x0644
95 #define DP0_TOTALVAL		0x0648
96 #define DP0_STARTVAL		0x064c
97 #define DP0_ACTIVEVAL		0x0650
98 #define DP0_SYNCVAL		0x0654
99 #define DP0_MISC		0x0658
100 #define TU_SIZE_RECOMMENDED		(0x3f << 16) /* LSCLK cycles per TU */
101 #define BPC_6				(0 << 5)
102 #define BPC_8				(1 << 5)
103 
104 /* AUX channel */
105 #define DP0_AUXCFG0		0x0660
106 #define DP0_AUXCFG1		0x0664
107 #define AUX_RX_FILTER_EN		BIT(16)
108 
109 #define DP0_AUXADDR		0x0668
110 #define DP0_AUXWDATA(i)		(0x066c + (i) * 4)
111 #define DP0_AUXRDATA(i)		(0x067c + (i) * 4)
112 #define DP0_AUXSTATUS		0x068c
113 #define AUX_STATUS_MASK			0xf0
114 #define AUX_STATUS_SHIFT		4
115 #define AUX_TIMEOUT			BIT(1)
116 #define AUX_BUSY			BIT(0)
117 #define DP0_AUXI2CADR		0x0698
118 
119 /* Link Training */
120 #define DP0_SRCCTRL		0x06a0
121 #define DP0_SRCCTRL_SCRMBLDIS		BIT(13)
122 #define DP0_SRCCTRL_EN810B		BIT(12)
123 #define DP0_SRCCTRL_NOTP		(0 << 8)
124 #define DP0_SRCCTRL_TP1			(1 << 8)
125 #define DP0_SRCCTRL_TP2			(2 << 8)
126 #define DP0_SRCCTRL_LANESKEW		BIT(7)
127 #define DP0_SRCCTRL_SSCG		BIT(3)
128 #define DP0_SRCCTRL_LANES_1		(0 << 2)
129 #define DP0_SRCCTRL_LANES_2		(1 << 2)
130 #define DP0_SRCCTRL_BW27		(1 << 1)
131 #define DP0_SRCCTRL_BW162		(0 << 1)
132 #define DP0_SRCCTRL_AUTOCORRECT		BIT(0)
133 #define DP0_LTSTAT		0x06d0
134 #define LT_LOOPDONE			BIT(13)
135 #define LT_STATUS_MASK			(0x1f << 8)
136 #define LT_CHANNEL1_EQ_BITS		(DP_CHANNEL_EQ_BITS << 4)
137 #define LT_INTERLANE_ALIGN_DONE		BIT(3)
138 #define LT_CHANNEL0_EQ_BITS		(DP_CHANNEL_EQ_BITS)
139 #define DP0_SNKLTCHGREQ		0x06d4
140 #define DP0_LTLOOPCTRL		0x06d8
141 #define DP0_SNKLTCTRL		0x06e4
142 
143 /* PHY */
144 #define DP_PHY_CTRL		0x0800
145 #define DP_PHY_RST			BIT(28)  /* DP PHY Global Soft Reset */
146 #define BGREN				BIT(25)  /* AUX PHY BGR Enable */
147 #define PWR_SW_EN			BIT(24)  /* PHY Power Switch Enable */
148 #define PHY_M1_RST			BIT(12)  /* Reset PHY1 Main Channel */
149 #define PHY_RDY				BIT(16)  /* PHY Main Channels Ready */
150 #define PHY_M0_RST			BIT(8)   /* Reset PHY0 Main Channel */
151 #define PHY_A0_EN			BIT(1)   /* PHY Aux Channel0 Enable */
152 #define PHY_M0_EN			BIT(0)   /* PHY Main Channel0 Enable */
153 
154 /* PLL */
155 #define DP0_PLLCTRL		0x0900
156 #define DP1_PLLCTRL		0x0904	/* not defined in DS */
157 #define PXL_PLLCTRL		0x0908
158 #define PLLUPDATE			BIT(2)
159 #define PLLBYP				BIT(1)
160 #define PLLEN				BIT(0)
161 #define PXL_PLLPARAM		0x0914
162 #define IN_SEL_REFCLK			(0 << 14)
163 #define SYS_PLLPARAM		0x0918
164 #define REF_FREQ_38M4			(0 << 8) /* 38.4 MHz */
165 #define REF_FREQ_19M2			(1 << 8) /* 19.2 MHz */
166 #define REF_FREQ_26M			(2 << 8) /* 26 MHz */
167 #define REF_FREQ_13M			(3 << 8) /* 13 MHz */
168 #define SYSCLK_SEL_LSCLK		(0 << 4)
169 #define LSCLK_DIV_1			(0 << 0)
170 #define LSCLK_DIV_2			(1 << 0)
171 
172 /* Test & Debug */
173 #define TSTCTL			0x0a00
174 #define PLL_DBG			0x0a04
175 
176 static bool tc_test_pattern;
177 module_param_named(test, tc_test_pattern, bool, 0644);
178 
179 struct tc_edp_link {
180 	struct drm_dp_link	base;
181 	u8			assr;
182 	int			scrambler_dis;
183 	int			spread;
184 	int			coding8b10b;
185 	u8			swing;
186 	u8			preemp;
187 };
188 
189 struct tc_data {
190 	struct device		*dev;
191 	struct regmap		*regmap;
192 	struct drm_dp_aux	aux;
193 
194 	struct drm_bridge	bridge;
195 	struct drm_connector	connector;
196 	struct drm_panel	*panel;
197 
198 	/* link settings */
199 	struct tc_edp_link	link;
200 
201 	/* display edid */
202 	struct edid		*edid;
203 	/* current mode */
204 	struct drm_display_mode	*mode;
205 
206 	u32			rev;
207 	u8			assr;
208 
209 	struct gpio_desc	*sd_gpio;
210 	struct gpio_desc	*reset_gpio;
211 	struct clk		*refclk;
212 };
213 
214 static inline struct tc_data *aux_to_tc(struct drm_dp_aux *a)
215 {
216 	return container_of(a, struct tc_data, aux);
217 }
218 
219 static inline struct tc_data *bridge_to_tc(struct drm_bridge *b)
220 {
221 	return container_of(b, struct tc_data, bridge);
222 }
223 
224 static inline struct tc_data *connector_to_tc(struct drm_connector *c)
225 {
226 	return container_of(c, struct tc_data, connector);
227 }
228 
229 /* Simple macros to avoid repeated error checks */
230 #define tc_write(reg, var)					\
231 	do {							\
232 		ret = regmap_write(tc->regmap, reg, var);	\
233 		if (ret)					\
234 			goto err;				\
235 	} while (0)
236 #define tc_read(reg, var)					\
237 	do {							\
238 		ret = regmap_read(tc->regmap, reg, var);	\
239 		if (ret)					\
240 			goto err;				\
241 	} while (0)
242 
243 static inline int tc_poll_timeout(struct regmap *map, unsigned int addr,
244 				  unsigned int cond_mask,
245 				  unsigned int cond_value,
246 				  unsigned long sleep_us, u64 timeout_us)
247 {
248 	ktime_t timeout = ktime_add_us(ktime_get(), timeout_us);
249 	unsigned int val;
250 	int ret;
251 
252 	for (;;) {
253 		ret = regmap_read(map, addr, &val);
254 		if (ret)
255 			break;
256 		if ((val & cond_mask) == cond_value)
257 			break;
258 		if (timeout_us && ktime_compare(ktime_get(), timeout) > 0) {
259 			ret = regmap_read(map, addr, &val);
260 			break;
261 		}
262 		if (sleep_us)
263 			usleep_range((sleep_us >> 2) + 1, sleep_us);
264 	}
265 	return ret ?: (((val & cond_mask) == cond_value) ? 0 : -ETIMEDOUT);
266 }
267 
268 static int tc_aux_wait_busy(struct tc_data *tc, unsigned int timeout_ms)
269 {
270 	return tc_poll_timeout(tc->regmap, DP0_AUXSTATUS, AUX_BUSY, 0,
271 			       1000, 1000 * timeout_ms);
272 }
273 
274 static int tc_aux_get_status(struct tc_data *tc, u8 *reply)
275 {
276 	int ret;
277 	u32 value;
278 
279 	ret = regmap_read(tc->regmap, DP0_AUXSTATUS, &value);
280 	if (ret < 0)
281 		return ret;
282 	if (value & AUX_BUSY) {
283 		if (value & AUX_TIMEOUT) {
284 			dev_err(tc->dev, "i2c access timeout!\n");
285 			return -ETIMEDOUT;
286 		}
287 		return -EBUSY;
288 	}
289 
290 	*reply = (value & AUX_STATUS_MASK) >> AUX_STATUS_SHIFT;
291 	return 0;
292 }
293 
294 static ssize_t tc_aux_transfer(struct drm_dp_aux *aux,
295 			       struct drm_dp_aux_msg *msg)
296 {
297 	struct tc_data *tc = aux_to_tc(aux);
298 	size_t size = min_t(size_t, 8, msg->size);
299 	u8 request = msg->request & ~DP_AUX_I2C_MOT;
300 	u8 *buf = msg->buffer;
301 	u32 tmp = 0;
302 	int i = 0;
303 	int ret;
304 
305 	if (size == 0)
306 		return 0;
307 
308 	ret = tc_aux_wait_busy(tc, 100);
309 	if (ret)
310 		goto err;
311 
312 	if (request == DP_AUX_I2C_WRITE || request == DP_AUX_NATIVE_WRITE) {
313 		/* Store data */
314 		while (i < size) {
315 			if (request == DP_AUX_NATIVE_WRITE)
316 				tmp = tmp | (buf[i] << (8 * (i & 0x3)));
317 			else
318 				tmp = (tmp << 8) | buf[i];
319 			i++;
320 			if (((i % 4) == 0) || (i == size)) {
321 				tc_write(DP0_AUXWDATA(i >> 2), tmp);
322 				tmp = 0;
323 			}
324 		}
325 	} else if (request != DP_AUX_I2C_READ &&
326 		   request != DP_AUX_NATIVE_READ) {
327 		return -EINVAL;
328 	}
329 
330 	/* Store address */
331 	tc_write(DP0_AUXADDR, msg->address);
332 	/* Start transfer */
333 	tc_write(DP0_AUXCFG0, ((size - 1) << 8) | request);
334 
335 	ret = tc_aux_wait_busy(tc, 100);
336 	if (ret)
337 		goto err;
338 
339 	ret = tc_aux_get_status(tc, &msg->reply);
340 	if (ret)
341 		goto err;
342 
343 	if (request == DP_AUX_I2C_READ || request == DP_AUX_NATIVE_READ) {
344 		/* Read data */
345 		while (i < size) {
346 			if ((i % 4) == 0)
347 				tc_read(DP0_AUXRDATA(i >> 2), &tmp);
348 			buf[i] = tmp & 0xff;
349 			tmp = tmp >> 8;
350 			i++;
351 		}
352 	}
353 
354 	return size;
355 err:
356 	return ret;
357 }
358 
359 static const char * const training_pattern1_errors[] = {
360 	"No errors",
361 	"Aux write error",
362 	"Aux read error",
363 	"Max voltage reached error",
364 	"Loop counter expired error",
365 	"res", "res", "res"
366 };
367 
368 static const char * const training_pattern2_errors[] = {
369 	"No errors",
370 	"Aux write error",
371 	"Aux read error",
372 	"Clock recovery failed error",
373 	"Loop counter expired error",
374 	"res", "res", "res"
375 };
376 
377 static u32 tc_srcctrl(struct tc_data *tc)
378 {
379 	/*
380 	 * No training pattern, skew lane 1 data by two LSCLK cycles with
381 	 * respect to lane 0 data, AutoCorrect Mode = 0
382 	 */
383 	u32 reg = DP0_SRCCTRL_NOTP | DP0_SRCCTRL_LANESKEW;
384 
385 	if (tc->link.scrambler_dis)
386 		reg |= DP0_SRCCTRL_SCRMBLDIS;	/* Scrambler Disabled */
387 	if (tc->link.coding8b10b)
388 		/* Enable 8/10B Encoder (TxData[19:16] not used) */
389 		reg |= DP0_SRCCTRL_EN810B;
390 	if (tc->link.spread)
391 		reg |= DP0_SRCCTRL_SSCG;	/* Spread Spectrum Enable */
392 	if (tc->link.base.num_lanes == 2)
393 		reg |= DP0_SRCCTRL_LANES_2;	/* Two Main Channel Lanes */
394 	if (tc->link.base.rate != 162000)
395 		reg |= DP0_SRCCTRL_BW27;	/* 2.7 Gbps link */
396 	return reg;
397 }
398 
399 static void tc_wait_pll_lock(struct tc_data *tc)
400 {
401 	/* Wait for PLL to lock: up to 2.09 ms, depending on refclk */
402 	usleep_range(3000, 6000);
403 }
404 
405 static int tc_pxl_pll_en(struct tc_data *tc, u32 refclk, u32 pixelclock)
406 {
407 	int ret;
408 	int i_pre, best_pre = 1;
409 	int i_post, best_post = 1;
410 	int div, best_div = 1;
411 	int mul, best_mul = 1;
412 	int delta, best_delta;
413 	int ext_div[] = {1, 2, 3, 5, 7};
414 	int best_pixelclock = 0;
415 	int vco_hi = 0;
416 
417 	dev_dbg(tc->dev, "PLL: requested %d pixelclock, ref %d\n", pixelclock,
418 		refclk);
419 	best_delta = pixelclock;
420 	/* Loop over all possible ext_divs, skipping invalid configurations */
421 	for (i_pre = 0; i_pre < ARRAY_SIZE(ext_div); i_pre++) {
422 		/*
423 		 * refclk / ext_pre_div should be in the 1 to 200 MHz range.
424 		 * We don't allow any refclk > 200 MHz, only check lower bounds.
425 		 */
426 		if (refclk / ext_div[i_pre] < 1000000)
427 			continue;
428 		for (i_post = 0; i_post < ARRAY_SIZE(ext_div); i_post++) {
429 			for (div = 1; div <= 16; div++) {
430 				u32 clk;
431 				u64 tmp;
432 
433 				tmp = pixelclock * ext_div[i_pre] *
434 				      ext_div[i_post] * div;
435 				do_div(tmp, refclk);
436 				mul = tmp;
437 
438 				/* Check limits */
439 				if ((mul < 1) || (mul > 128))
440 					continue;
441 
442 				clk = (refclk / ext_div[i_pre] / div) * mul;
443 				/*
444 				 * refclk * mul / (ext_pre_div * pre_div)
445 				 * should be in the 150 to 650 MHz range
446 				 */
447 				if ((clk > 650000000) || (clk < 150000000))
448 					continue;
449 
450 				clk = clk / ext_div[i_post];
451 				delta = clk - pixelclock;
452 
453 				if (abs(delta) < abs(best_delta)) {
454 					best_pre = i_pre;
455 					best_post = i_post;
456 					best_div = div;
457 					best_mul = mul;
458 					best_delta = delta;
459 					best_pixelclock = clk;
460 				}
461 			}
462 		}
463 	}
464 	if (best_pixelclock == 0) {
465 		dev_err(tc->dev, "Failed to calc clock for %d pixelclock\n",
466 			pixelclock);
467 		return -EINVAL;
468 	}
469 
470 	dev_dbg(tc->dev, "PLL: got %d, delta %d\n", best_pixelclock,
471 		best_delta);
472 	dev_dbg(tc->dev, "PLL: %d / %d / %d * %d / %d\n", refclk,
473 		ext_div[best_pre], best_div, best_mul, ext_div[best_post]);
474 
475 	/* if VCO >= 300 MHz */
476 	if (refclk / ext_div[best_pre] / best_div * best_mul >= 300000000)
477 		vco_hi = 1;
478 	/* see DS */
479 	if (best_div == 16)
480 		best_div = 0;
481 	if (best_mul == 128)
482 		best_mul = 0;
483 
484 	/* Power up PLL and switch to bypass */
485 	tc_write(PXL_PLLCTRL, PLLBYP | PLLEN);
486 
487 	tc_write(PXL_PLLPARAM,
488 		 (vco_hi << 24) |		/* For PLL VCO >= 300 MHz = 1 */
489 		 (ext_div[best_pre] << 20) |	/* External Pre-divider */
490 		 (ext_div[best_post] << 16) |	/* External Post-divider */
491 		 IN_SEL_REFCLK |		/* Use RefClk as PLL input */
492 		 (best_div << 8) |		/* Divider for PLL RefClk */
493 		 (best_mul << 0));		/* Multiplier for PLL */
494 
495 	/* Force PLL parameter update and disable bypass */
496 	tc_write(PXL_PLLCTRL, PLLUPDATE | PLLEN);
497 
498 	tc_wait_pll_lock(tc);
499 
500 	return 0;
501 err:
502 	return ret;
503 }
504 
505 static int tc_pxl_pll_dis(struct tc_data *tc)
506 {
507 	/* Enable PLL bypass, power down PLL */
508 	return regmap_write(tc->regmap, PXL_PLLCTRL, PLLBYP);
509 }
510 
511 static int tc_stream_clock_calc(struct tc_data *tc)
512 {
513 	int ret;
514 	/*
515 	 * If the Stream clock and Link Symbol clock are
516 	 * asynchronous with each other, the value of M changes over
517 	 * time. This way of generating link clock and stream
518 	 * clock is called Asynchronous Clock mode. The value M
519 	 * must change while the value N stays constant. The
520 	 * value of N in this Asynchronous Clock mode must be set
521 	 * to 2^15 or 32,768.
522 	 *
523 	 * LSCLK = 1/10 of high speed link clock
524 	 *
525 	 * f_STRMCLK = M/N * f_LSCLK
526 	 * M/N = f_STRMCLK / f_LSCLK
527 	 *
528 	 */
529 	tc_write(DP0_VIDMNGEN1, 32768);
530 
531 	return 0;
532 err:
533 	return ret;
534 }
535 
536 static int tc_aux_link_setup(struct tc_data *tc)
537 {
538 	unsigned long rate;
539 	u32 value;
540 	int ret;
541 
542 	rate = clk_get_rate(tc->refclk);
543 	switch (rate) {
544 	case 38400000:
545 		value = REF_FREQ_38M4;
546 		break;
547 	case 26000000:
548 		value = REF_FREQ_26M;
549 		break;
550 	case 19200000:
551 		value = REF_FREQ_19M2;
552 		break;
553 	case 13000000:
554 		value = REF_FREQ_13M;
555 		break;
556 	default:
557 		dev_err(tc->dev, "Invalid refclk rate: %lu Hz\n", rate);
558 		return -EINVAL;
559 	}
560 
561 	/* Setup DP-PHY / PLL */
562 	value |= SYSCLK_SEL_LSCLK | LSCLK_DIV_2;
563 	tc_write(SYS_PLLPARAM, value);
564 
565 	tc_write(DP_PHY_CTRL, BGREN | PWR_SW_EN | BIT(2) | PHY_A0_EN);
566 
567 	/*
568 	 * Initially PLLs are in bypass. Force PLL parameter update,
569 	 * disable PLL bypass, enable PLL
570 	 */
571 	tc_write(DP0_PLLCTRL, PLLUPDATE | PLLEN);
572 	tc_wait_pll_lock(tc);
573 
574 	tc_write(DP1_PLLCTRL, PLLUPDATE | PLLEN);
575 	tc_wait_pll_lock(tc);
576 
577 	ret = tc_poll_timeout(tc->regmap, DP_PHY_CTRL, PHY_RDY, PHY_RDY, 1,
578 			      1000);
579 	if (ret == -ETIMEDOUT) {
580 		dev_err(tc->dev, "Timeout waiting for PHY to become ready");
581 		return ret;
582 	} else if (ret)
583 		goto err;
584 
585 	/* Setup AUX link */
586 	tc_write(DP0_AUXCFG1, AUX_RX_FILTER_EN |
587 		 (0x06 << 8) |	/* Aux Bit Period Calculator Threshold */
588 		 (0x3f << 0));	/* Aux Response Timeout Timer */
589 
590 	return 0;
591 err:
592 	dev_err(tc->dev, "tc_aux_link_setup failed: %d\n", ret);
593 	return ret;
594 }
595 
596 static int tc_get_display_props(struct tc_data *tc)
597 {
598 	int ret;
599 	/* temp buffer */
600 	u8 tmp[8];
601 
602 	/* Read DP Rx Link Capability */
603 	ret = drm_dp_link_probe(&tc->aux, &tc->link.base);
604 	if (ret < 0)
605 		goto err_dpcd_read;
606 	if ((tc->link.base.rate != 162000) && (tc->link.base.rate != 270000))
607 		goto err_dpcd_inval;
608 
609 	ret = drm_dp_dpcd_readb(&tc->aux, DP_MAX_DOWNSPREAD, tmp);
610 	if (ret < 0)
611 		goto err_dpcd_read;
612 	tc->link.spread = tmp[0] & BIT(0); /* 0.5% down spread */
613 
614 	ret = drm_dp_dpcd_readb(&tc->aux, DP_MAIN_LINK_CHANNEL_CODING, tmp);
615 	if (ret < 0)
616 		goto err_dpcd_read;
617 	tc->link.coding8b10b = tmp[0] & BIT(0);
618 	tc->link.scrambler_dis = 0;
619 	/* read assr */
620 	ret = drm_dp_dpcd_readb(&tc->aux, DP_EDP_CONFIGURATION_SET, tmp);
621 	if (ret < 0)
622 		goto err_dpcd_read;
623 	tc->link.assr = tmp[0] & DP_ALTERNATE_SCRAMBLER_RESET_ENABLE;
624 
625 	dev_dbg(tc->dev, "DPCD rev: %d.%d, rate: %s, lanes: %d, framing: %s\n",
626 		tc->link.base.revision >> 4, tc->link.base.revision & 0x0f,
627 		(tc->link.base.rate == 162000) ? "1.62Gbps" : "2.7Gbps",
628 		tc->link.base.num_lanes,
629 		(tc->link.base.capabilities & DP_LINK_CAP_ENHANCED_FRAMING) ?
630 		"enhanced" : "non-enhanced");
631 	dev_dbg(tc->dev, "ANSI 8B/10B: %d\n", tc->link.coding8b10b);
632 	dev_dbg(tc->dev, "Display ASSR: %d, TC358767 ASSR: %d\n",
633 		tc->link.assr, tc->assr);
634 
635 	return 0;
636 
637 err_dpcd_read:
638 	dev_err(tc->dev, "failed to read DPCD: %d\n", ret);
639 	return ret;
640 err_dpcd_inval:
641 	dev_err(tc->dev, "invalid DPCD\n");
642 	return -EINVAL;
643 }
644 
645 static int tc_set_video_mode(struct tc_data *tc, struct drm_display_mode *mode)
646 {
647 	int ret;
648 	int vid_sync_dly;
649 	int max_tu_symbol;
650 
651 	int left_margin = mode->htotal - mode->hsync_end;
652 	int right_margin = mode->hsync_start - mode->hdisplay;
653 	int hsync_len = mode->hsync_end - mode->hsync_start;
654 	int upper_margin = mode->vtotal - mode->vsync_end;
655 	int lower_margin = mode->vsync_start - mode->vdisplay;
656 	int vsync_len = mode->vsync_end - mode->vsync_start;
657 
658 	dev_dbg(tc->dev, "set mode %dx%d\n",
659 		mode->hdisplay, mode->vdisplay);
660 	dev_dbg(tc->dev, "H margin %d,%d sync %d\n",
661 		left_margin, right_margin, hsync_len);
662 	dev_dbg(tc->dev, "V margin %d,%d sync %d\n",
663 		upper_margin, lower_margin, vsync_len);
664 	dev_dbg(tc->dev, "total: %dx%d\n", mode->htotal, mode->vtotal);
665 
666 
667 	/* LCD Ctl Frame Size */
668 	tc_write(VPCTRL0, (0x40 << 20) /* VSDELAY */ |
669 		 OPXLFMT_RGB888 | FRMSYNC_DISABLED | MSF_DISABLED);
670 	tc_write(HTIM01, (left_margin << 16) |		/* H back porch */
671 			 (hsync_len << 0));		/* Hsync */
672 	tc_write(HTIM02, (right_margin << 16) |		/* H front porch */
673 			 (mode->hdisplay << 0));	/* width */
674 	tc_write(VTIM01, (upper_margin << 16) |		/* V back porch */
675 			 (vsync_len << 0));		/* Vsync */
676 	tc_write(VTIM02, (lower_margin << 16) |		/* V front porch */
677 			 (mode->vdisplay << 0));	/* height */
678 	tc_write(VFUEN0, VFUEN);		/* update settings */
679 
680 	/* Test pattern settings */
681 	tc_write(TSTCTL,
682 		 (120 << 24) |	/* Red Color component value */
683 		 (20 << 16) |	/* Green Color component value */
684 		 (99 << 8) |	/* Blue Color component value */
685 		 (1 << 4) |	/* Enable I2C Filter */
686 		 (2 << 0) |	/* Color bar Mode */
687 		 0);
688 
689 	/* DP Main Stream Attributes */
690 	vid_sync_dly = hsync_len + left_margin + mode->hdisplay;
691 	tc_write(DP0_VIDSYNCDELAY,
692 		 (0x003e << 16) |	/* thresh_dly */
693 		 (vid_sync_dly << 0));
694 
695 	tc_write(DP0_TOTALVAL, (mode->vtotal << 16) | (mode->htotal));
696 
697 	tc_write(DP0_STARTVAL,
698 		 ((upper_margin + vsync_len) << 16) |
699 		 ((left_margin + hsync_len) << 0));
700 
701 	tc_write(DP0_ACTIVEVAL, (mode->vdisplay << 16) | (mode->hdisplay));
702 
703 	tc_write(DP0_SYNCVAL, (vsync_len << 16) | (hsync_len << 0));
704 
705 	tc_write(DPIPXLFMT, VS_POL_ACTIVE_LOW | HS_POL_ACTIVE_LOW |
706 		 DE_POL_ACTIVE_HIGH | SUB_CFG_TYPE_CONFIG1 | DPI_BPP_RGB888);
707 
708 	/*
709 	 * Recommended maximum number of symbols transferred in a transfer unit:
710 	 * DIV_ROUND_UP((input active video bandwidth in bytes) * tu_size,
711 	 *              (output active video bandwidth in bytes))
712 	 * Must be less than tu_size.
713 	 */
714 	max_tu_symbol = TU_SIZE_RECOMMENDED - 1;
715 	tc_write(DP0_MISC, (max_tu_symbol << 23) | TU_SIZE_RECOMMENDED | BPC_8);
716 
717 	return 0;
718 err:
719 	return ret;
720 }
721 
722 static int tc_link_training(struct tc_data *tc, int pattern)
723 {
724 	const char * const *errors;
725 	u32 srcctrl = tc_srcctrl(tc) | DP0_SRCCTRL_SCRMBLDIS |
726 		      DP0_SRCCTRL_AUTOCORRECT;
727 	int timeout;
728 	int retry;
729 	u32 value;
730 	int ret;
731 
732 	if (pattern == DP_TRAINING_PATTERN_1) {
733 		srcctrl |= DP0_SRCCTRL_TP1;
734 		errors = training_pattern1_errors;
735 	} else {
736 		srcctrl |= DP0_SRCCTRL_TP2;
737 		errors = training_pattern2_errors;
738 	}
739 
740 	/* Set DPCD 0x102 for Training Part 1 or 2 */
741 	tc_write(DP0_SNKLTCTRL, DP_LINK_SCRAMBLING_DISABLE | pattern);
742 
743 	tc_write(DP0_LTLOOPCTRL,
744 		 (0x0f << 28) |	/* Defer Iteration Count */
745 		 (0x0f << 24) |	/* Loop Iteration Count */
746 		 (0x0d << 0));	/* Loop Timer Delay */
747 
748 	retry = 5;
749 	do {
750 		/* Set DP0 Training Pattern */
751 		tc_write(DP0_SRCCTRL, srcctrl);
752 
753 		/* Enable DP0 to start Link Training */
754 		tc_write(DP0CTL, DP_EN);
755 
756 		/* wait */
757 		timeout = 1000;
758 		do {
759 			tc_read(DP0_LTSTAT, &value);
760 			udelay(1);
761 		} while ((!(value & LT_LOOPDONE)) && (--timeout));
762 		if (timeout == 0) {
763 			dev_err(tc->dev, "Link training timeout!\n");
764 		} else {
765 			int pattern = (value >> 11) & 0x3;
766 			int error = (value >> 8) & 0x7;
767 
768 			dev_dbg(tc->dev,
769 				"Link training phase %d done after %d uS: %s\n",
770 				pattern, 1000 - timeout, errors[error]);
771 			if (pattern == DP_TRAINING_PATTERN_1 && error == 0)
772 				break;
773 			if (pattern == DP_TRAINING_PATTERN_2) {
774 				value &= LT_CHANNEL1_EQ_BITS |
775 					 LT_INTERLANE_ALIGN_DONE |
776 					 LT_CHANNEL0_EQ_BITS;
777 				/* in case of two lanes */
778 				if ((tc->link.base.num_lanes == 2) &&
779 				    (value == (LT_CHANNEL1_EQ_BITS |
780 					       LT_INTERLANE_ALIGN_DONE |
781 					       LT_CHANNEL0_EQ_BITS)))
782 					break;
783 				/* in case of one line */
784 				if ((tc->link.base.num_lanes == 1) &&
785 				    (value == (LT_INTERLANE_ALIGN_DONE |
786 					       LT_CHANNEL0_EQ_BITS)))
787 					break;
788 			}
789 		}
790 		/* restart */
791 		tc_write(DP0CTL, 0);
792 		usleep_range(10, 20);
793 	} while (--retry);
794 	if (retry == 0) {
795 		dev_err(tc->dev, "Failed to finish training phase %d\n",
796 			pattern);
797 	}
798 
799 	return 0;
800 err:
801 	return ret;
802 }
803 
804 static int tc_main_link_setup(struct tc_data *tc)
805 {
806 	struct drm_dp_aux *aux = &tc->aux;
807 	struct device *dev = tc->dev;
808 	unsigned int rate;
809 	u32 dp_phy_ctrl;
810 	int timeout;
811 	bool aligned;
812 	bool ready;
813 	u32 value;
814 	int ret;
815 	u8 tmp[8];
816 
817 	/* display mode should be set at this point */
818 	if (!tc->mode)
819 		return -EINVAL;
820 
821 	/* from excel file - DP0_SrcCtrl */
822 	tc_write(DP0_SRCCTRL, DP0_SRCCTRL_SCRMBLDIS | DP0_SRCCTRL_EN810B |
823 		 DP0_SRCCTRL_LANESKEW | DP0_SRCCTRL_LANES_2 |
824 		 DP0_SRCCTRL_BW27 | DP0_SRCCTRL_AUTOCORRECT);
825 	/* from excel file - DP1_SrcCtrl */
826 	tc_write(0x07a0, 0x00003083);
827 
828 	rate = clk_get_rate(tc->refclk);
829 	switch (rate) {
830 	case 38400000:
831 		value = REF_FREQ_38M4;
832 		break;
833 	case 26000000:
834 		value = REF_FREQ_26M;
835 		break;
836 	case 19200000:
837 		value = REF_FREQ_19M2;
838 		break;
839 	case 13000000:
840 		value = REF_FREQ_13M;
841 		break;
842 	default:
843 		return -EINVAL;
844 	}
845 	value |= SYSCLK_SEL_LSCLK | LSCLK_DIV_2;
846 	tc_write(SYS_PLLPARAM, value);
847 	/* Setup Main Link */
848 	dp_phy_ctrl = BGREN | PWR_SW_EN | BIT(2) | PHY_A0_EN |  PHY_M0_EN;
849 	tc_write(DP_PHY_CTRL, dp_phy_ctrl);
850 	msleep(100);
851 
852 	/* PLL setup */
853 	tc_write(DP0_PLLCTRL, PLLUPDATE | PLLEN);
854 	tc_wait_pll_lock(tc);
855 
856 	tc_write(DP1_PLLCTRL, PLLUPDATE | PLLEN);
857 	tc_wait_pll_lock(tc);
858 
859 	/* PXL PLL setup */
860 	if (tc_test_pattern) {
861 		ret = tc_pxl_pll_en(tc, clk_get_rate(tc->refclk),
862 				    1000 * tc->mode->clock);
863 		if (ret)
864 			goto err;
865 	}
866 
867 	/* Reset/Enable Main Links */
868 	dp_phy_ctrl |= DP_PHY_RST | PHY_M1_RST | PHY_M0_RST;
869 	tc_write(DP_PHY_CTRL, dp_phy_ctrl);
870 	usleep_range(100, 200);
871 	dp_phy_ctrl &= ~(DP_PHY_RST | PHY_M1_RST | PHY_M0_RST);
872 	tc_write(DP_PHY_CTRL, dp_phy_ctrl);
873 
874 	timeout = 1000;
875 	do {
876 		tc_read(DP_PHY_CTRL, &value);
877 		udelay(1);
878 	} while ((!(value & PHY_RDY)) && (--timeout));
879 
880 	if (timeout == 0) {
881 		dev_err(dev, "timeout waiting for phy become ready");
882 		return -ETIMEDOUT;
883 	}
884 
885 	/* Set misc: 8 bits per color */
886 	ret = regmap_update_bits(tc->regmap, DP0_MISC, BPC_8, BPC_8);
887 	if (ret)
888 		goto err;
889 
890 	/*
891 	 * ASSR mode
892 	 * on TC358767 side ASSR configured through strap pin
893 	 * seems there is no way to change this setting from SW
894 	 *
895 	 * check is tc configured for same mode
896 	 */
897 	if (tc->assr != tc->link.assr) {
898 		dev_dbg(dev, "Trying to set display to ASSR: %d\n",
899 			tc->assr);
900 		/* try to set ASSR on display side */
901 		tmp[0] = tc->assr;
902 		ret = drm_dp_dpcd_writeb(aux, DP_EDP_CONFIGURATION_SET, tmp[0]);
903 		if (ret < 0)
904 			goto err_dpcd_read;
905 		/* read back */
906 		ret = drm_dp_dpcd_readb(aux, DP_EDP_CONFIGURATION_SET, tmp);
907 		if (ret < 0)
908 			goto err_dpcd_read;
909 
910 		if (tmp[0] != tc->assr) {
911 			dev_dbg(dev, "Failed to switch display ASSR to %d, falling back to unscrambled mode\n",
912 				 tc->assr);
913 			/* trying with disabled scrambler */
914 			tc->link.scrambler_dis = 1;
915 		}
916 	}
917 
918 	/* Setup Link & DPRx Config for Training */
919 	ret = drm_dp_link_configure(aux, &tc->link.base);
920 	if (ret < 0)
921 		goto err_dpcd_write;
922 
923 	/* DOWNSPREAD_CTRL */
924 	tmp[0] = tc->link.spread ? DP_SPREAD_AMP_0_5 : 0x00;
925 	/* MAIN_LINK_CHANNEL_CODING_SET */
926 	tmp[1] =  tc->link.coding8b10b ? DP_SET_ANSI_8B10B : 0x00;
927 	ret = drm_dp_dpcd_write(aux, DP_DOWNSPREAD_CTRL, tmp, 2);
928 	if (ret < 0)
929 		goto err_dpcd_write;
930 
931 	ret = tc_link_training(tc, DP_TRAINING_PATTERN_1);
932 	if (ret)
933 		goto err;
934 
935 	ret = tc_link_training(tc, DP_TRAINING_PATTERN_2);
936 	if (ret)
937 		goto err;
938 
939 	/* Clear DPCD 0x102 */
940 	/* Note: Can Not use DP0_SNKLTCTRL (0x06E4) short cut */
941 	tmp[0] = tc->link.scrambler_dis ? DP_LINK_SCRAMBLING_DISABLE : 0x00;
942 	ret = drm_dp_dpcd_writeb(aux, DP_TRAINING_PATTERN_SET, tmp[0]);
943 	if (ret < 0)
944 		goto err_dpcd_write;
945 
946 	/* Clear Training Pattern, set AutoCorrect Mode = 1 */
947 	tc_write(DP0_SRCCTRL, tc_srcctrl(tc) | DP0_SRCCTRL_AUTOCORRECT);
948 
949 	/* Wait */
950 	timeout = 100;
951 	do {
952 		udelay(1);
953 		/* Read DPCD 0x202-0x207 */
954 		ret = drm_dp_dpcd_read_link_status(aux, tmp + 2);
955 		if (ret < 0)
956 			goto err_dpcd_read;
957 		ready = (tmp[2] == ((DP_CHANNEL_EQ_BITS << 4) | /* Lane1 */
958 				     DP_CHANNEL_EQ_BITS));      /* Lane0 */
959 		aligned = tmp[4] & DP_INTERLANE_ALIGN_DONE;
960 	} while ((--timeout) && !(ready && aligned));
961 
962 	if (timeout == 0) {
963 		/* Read DPCD 0x200-0x201 */
964 		ret = drm_dp_dpcd_read(aux, DP_SINK_COUNT, tmp, 2);
965 		if (ret < 0)
966 			goto err_dpcd_read;
967 		dev_info(dev, "0x0200 SINK_COUNT: 0x%02x\n", tmp[0]);
968 		dev_info(dev, "0x0201 DEVICE_SERVICE_IRQ_VECTOR: 0x%02x\n",
969 			 tmp[1]);
970 		dev_info(dev, "0x0202 LANE0_1_STATUS: 0x%02x\n", tmp[2]);
971 		dev_info(dev, "0x0204 LANE_ALIGN_STATUS_UPDATED: 0x%02x\n",
972 			 tmp[4]);
973 		dev_info(dev, "0x0205 SINK_STATUS: 0x%02x\n", tmp[5]);
974 		dev_info(dev, "0x0206 ADJUST_REQUEST_LANE0_1: 0x%02x\n",
975 			 tmp[6]);
976 
977 		if (!ready)
978 			dev_err(dev, "Lane0/1 not ready\n");
979 		if (!aligned)
980 			dev_err(dev, "Lane0/1 not aligned\n");
981 		return -EAGAIN;
982 	}
983 
984 	ret = tc_set_video_mode(tc, tc->mode);
985 	if (ret)
986 		goto err;
987 
988 	/* Set M/N */
989 	ret = tc_stream_clock_calc(tc);
990 	if (ret)
991 		goto err;
992 
993 	return 0;
994 err_dpcd_read:
995 	dev_err(tc->dev, "Failed to read DPCD: %d\n", ret);
996 	return ret;
997 err_dpcd_write:
998 	dev_err(tc->dev, "Failed to write DPCD: %d\n", ret);
999 err:
1000 	return ret;
1001 }
1002 
1003 static int tc_main_link_stream(struct tc_data *tc, int state)
1004 {
1005 	int ret;
1006 	u32 value;
1007 
1008 	dev_dbg(tc->dev, "stream: %d\n", state);
1009 
1010 	if (state) {
1011 		value = VID_MN_GEN | DP_EN;
1012 		if (tc->link.base.capabilities & DP_LINK_CAP_ENHANCED_FRAMING)
1013 			value |= EF_EN;
1014 		tc_write(DP0CTL, value);
1015 		/*
1016 		 * VID_EN assertion should be delayed by at least N * LSCLK
1017 		 * cycles from the time VID_MN_GEN is enabled in order to
1018 		 * generate stable values for VID_M. LSCLK is 270 MHz or
1019 		 * 162 MHz, VID_N is set to 32768 in  tc_stream_clock_calc(),
1020 		 * so a delay of at least 203 us should suffice.
1021 		 */
1022 		usleep_range(500, 1000);
1023 		value |= VID_EN;
1024 		tc_write(DP0CTL, value);
1025 		/* Set input interface */
1026 		value = DP0_AUDSRC_NO_INPUT;
1027 		if (tc_test_pattern)
1028 			value |= DP0_VIDSRC_COLOR_BAR;
1029 		else
1030 			value |= DP0_VIDSRC_DPI_RX;
1031 		tc_write(SYSCTRL, value);
1032 	} else {
1033 		tc_write(DP0CTL, 0);
1034 	}
1035 
1036 	return 0;
1037 err:
1038 	return ret;
1039 }
1040 
1041 static void tc_bridge_pre_enable(struct drm_bridge *bridge)
1042 {
1043 	struct tc_data *tc = bridge_to_tc(bridge);
1044 
1045 	drm_panel_prepare(tc->panel);
1046 }
1047 
1048 static void tc_bridge_enable(struct drm_bridge *bridge)
1049 {
1050 	struct tc_data *tc = bridge_to_tc(bridge);
1051 	int ret;
1052 
1053 	ret = tc_main_link_setup(tc);
1054 	if (ret < 0) {
1055 		dev_err(tc->dev, "main link setup error: %d\n", ret);
1056 		return;
1057 	}
1058 
1059 	ret = tc_main_link_stream(tc, 1);
1060 	if (ret < 0) {
1061 		dev_err(tc->dev, "main link stream start error: %d\n", ret);
1062 		return;
1063 	}
1064 
1065 	drm_panel_enable(tc->panel);
1066 }
1067 
1068 static void tc_bridge_disable(struct drm_bridge *bridge)
1069 {
1070 	struct tc_data *tc = bridge_to_tc(bridge);
1071 	int ret;
1072 
1073 	drm_panel_disable(tc->panel);
1074 
1075 	ret = tc_main_link_stream(tc, 0);
1076 	if (ret < 0)
1077 		dev_err(tc->dev, "main link stream stop error: %d\n", ret);
1078 }
1079 
1080 static void tc_bridge_post_disable(struct drm_bridge *bridge)
1081 {
1082 	struct tc_data *tc = bridge_to_tc(bridge);
1083 
1084 	drm_panel_unprepare(tc->panel);
1085 }
1086 
1087 static bool tc_bridge_mode_fixup(struct drm_bridge *bridge,
1088 				 const struct drm_display_mode *mode,
1089 				 struct drm_display_mode *adj)
1090 {
1091 	/* Fixup sync polarities, both hsync and vsync are active low */
1092 	adj->flags = mode->flags;
1093 	adj->flags |= (DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC);
1094 	adj->flags &= ~(DRM_MODE_FLAG_PHSYNC | DRM_MODE_FLAG_PVSYNC);
1095 
1096 	return true;
1097 }
1098 
1099 static int tc_connector_mode_valid(struct drm_connector *connector,
1100 				   struct drm_display_mode *mode)
1101 {
1102 	/* Accept any mode */
1103 	return MODE_OK;
1104 }
1105 
1106 static void tc_bridge_mode_set(struct drm_bridge *bridge,
1107 			       struct drm_display_mode *mode,
1108 			       struct drm_display_mode *adj)
1109 {
1110 	struct tc_data *tc = bridge_to_tc(bridge);
1111 
1112 	tc->mode = mode;
1113 }
1114 
1115 static int tc_connector_get_modes(struct drm_connector *connector)
1116 {
1117 	struct tc_data *tc = connector_to_tc(connector);
1118 	struct edid *edid;
1119 	unsigned int count;
1120 
1121 	if (tc->panel && tc->panel->funcs && tc->panel->funcs->get_modes) {
1122 		count = tc->panel->funcs->get_modes(tc->panel);
1123 		if (count > 0)
1124 			return count;
1125 	}
1126 
1127 	edid = drm_get_edid(connector, &tc->aux.ddc);
1128 
1129 	kfree(tc->edid);
1130 	tc->edid = edid;
1131 	if (!edid)
1132 		return 0;
1133 
1134 	drm_mode_connector_update_edid_property(connector, edid);
1135 	count = drm_add_edid_modes(connector, edid);
1136 
1137 	return count;
1138 }
1139 
1140 static void tc_connector_set_polling(struct tc_data *tc,
1141 				     struct drm_connector *connector)
1142 {
1143 	/* TODO: add support for HPD */
1144 	connector->polled = DRM_CONNECTOR_POLL_CONNECT |
1145 			    DRM_CONNECTOR_POLL_DISCONNECT;
1146 }
1147 
1148 static struct drm_encoder *
1149 tc_connector_best_encoder(struct drm_connector *connector)
1150 {
1151 	struct tc_data *tc = connector_to_tc(connector);
1152 
1153 	return tc->bridge.encoder;
1154 }
1155 
1156 static const struct drm_connector_helper_funcs tc_connector_helper_funcs = {
1157 	.get_modes = tc_connector_get_modes,
1158 	.mode_valid = tc_connector_mode_valid,
1159 	.best_encoder = tc_connector_best_encoder,
1160 };
1161 
1162 static const struct drm_connector_funcs tc_connector_funcs = {
1163 	.dpms = drm_atomic_helper_connector_dpms,
1164 	.fill_modes = drm_helper_probe_single_connector_modes,
1165 	.destroy = drm_connector_cleanup,
1166 	.reset = drm_atomic_helper_connector_reset,
1167 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
1168 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
1169 };
1170 
1171 static int tc_bridge_attach(struct drm_bridge *bridge)
1172 {
1173 	u32 bus_format = MEDIA_BUS_FMT_RGB888_1X24;
1174 	struct tc_data *tc = bridge_to_tc(bridge);
1175 	struct drm_device *drm = bridge->dev;
1176 	int ret;
1177 
1178 	/* Create eDP connector */
1179 	drm_connector_helper_add(&tc->connector, &tc_connector_helper_funcs);
1180 	ret = drm_connector_init(drm, &tc->connector, &tc_connector_funcs,
1181 				 DRM_MODE_CONNECTOR_eDP);
1182 	if (ret)
1183 		return ret;
1184 
1185 	if (tc->panel)
1186 		drm_panel_attach(tc->panel, &tc->connector);
1187 
1188 	drm_display_info_set_bus_formats(&tc->connector.display_info,
1189 					 &bus_format, 1);
1190 	drm_mode_connector_attach_encoder(&tc->connector, tc->bridge.encoder);
1191 
1192 	return 0;
1193 }
1194 
1195 static const struct drm_bridge_funcs tc_bridge_funcs = {
1196 	.attach = tc_bridge_attach,
1197 	.mode_set = tc_bridge_mode_set,
1198 	.pre_enable = tc_bridge_pre_enable,
1199 	.enable = tc_bridge_enable,
1200 	.disable = tc_bridge_disable,
1201 	.post_disable = tc_bridge_post_disable,
1202 	.mode_fixup = tc_bridge_mode_fixup,
1203 };
1204 
1205 static bool tc_readable_reg(struct device *dev, unsigned int reg)
1206 {
1207 	return reg != SYSCTRL;
1208 }
1209 
1210 static const struct regmap_range tc_volatile_ranges[] = {
1211 	regmap_reg_range(DP0_AUXWDATA(0), DP0_AUXSTATUS),
1212 	regmap_reg_range(DP0_LTSTAT, DP0_SNKLTCHGREQ),
1213 	regmap_reg_range(DP_PHY_CTRL, DP_PHY_CTRL),
1214 	regmap_reg_range(DP0_PLLCTRL, PXL_PLLCTRL),
1215 	regmap_reg_range(VFUEN0, VFUEN0),
1216 };
1217 
1218 static const struct regmap_access_table tc_volatile_table = {
1219 	.yes_ranges = tc_volatile_ranges,
1220 	.n_yes_ranges = ARRAY_SIZE(tc_volatile_ranges),
1221 };
1222 
1223 static bool tc_writeable_reg(struct device *dev, unsigned int reg)
1224 {
1225 	return (reg != TC_IDREG) &&
1226 	       (reg != DP0_LTSTAT) &&
1227 	       (reg != DP0_SNKLTCHGREQ);
1228 }
1229 
1230 static const struct regmap_config tc_regmap_config = {
1231 	.name = "tc358767",
1232 	.reg_bits = 16,
1233 	.val_bits = 32,
1234 	.reg_stride = 4,
1235 	.max_register = PLL_DBG,
1236 	.cache_type = REGCACHE_RBTREE,
1237 	.readable_reg = tc_readable_reg,
1238 	.volatile_table = &tc_volatile_table,
1239 	.writeable_reg = tc_writeable_reg,
1240 	.reg_format_endian = REGMAP_ENDIAN_BIG,
1241 	.val_format_endian = REGMAP_ENDIAN_LITTLE,
1242 };
1243 
1244 static int tc_probe(struct i2c_client *client, const struct i2c_device_id *id)
1245 {
1246 	struct device *dev = &client->dev;
1247 	struct device_node *ep;
1248 	struct tc_data *tc;
1249 	int ret;
1250 
1251 	tc = devm_kzalloc(dev, sizeof(*tc), GFP_KERNEL);
1252 	if (!tc)
1253 		return -ENOMEM;
1254 
1255 	tc->dev = dev;
1256 
1257 	/* port@2 is the output port */
1258 	ep = of_graph_get_endpoint_by_regs(dev->of_node, 2, -1);
1259 	if (ep) {
1260 		struct device_node *remote;
1261 
1262 		remote = of_graph_get_remote_port_parent(ep);
1263 		if (!remote) {
1264 			dev_warn(dev, "endpoint %s not connected\n",
1265 				 ep->full_name);
1266 			of_node_put(ep);
1267 			return -ENODEV;
1268 		}
1269 		of_node_put(ep);
1270 		tc->panel = of_drm_find_panel(remote);
1271 		if (tc->panel) {
1272 			dev_dbg(dev, "found panel %s\n", remote->full_name);
1273 		} else {
1274 			dev_dbg(dev, "waiting for panel %s\n",
1275 				remote->full_name);
1276 			of_node_put(remote);
1277 			return -EPROBE_DEFER;
1278 		}
1279 		of_node_put(remote);
1280 	}
1281 
1282 	/* Shut down GPIO is optional */
1283 	tc->sd_gpio = devm_gpiod_get_optional(dev, "shutdown", GPIOD_OUT_HIGH);
1284 	if (IS_ERR(tc->sd_gpio))
1285 		return PTR_ERR(tc->sd_gpio);
1286 
1287 	if (tc->sd_gpio) {
1288 		gpiod_set_value_cansleep(tc->sd_gpio, 0);
1289 		usleep_range(5000, 10000);
1290 	}
1291 
1292 	/* Reset GPIO is optional */
1293 	tc->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
1294 	if (IS_ERR(tc->reset_gpio))
1295 		return PTR_ERR(tc->reset_gpio);
1296 
1297 	if (tc->reset_gpio) {
1298 		gpiod_set_value_cansleep(tc->reset_gpio, 1);
1299 		usleep_range(5000, 10000);
1300 	}
1301 
1302 	tc->refclk = devm_clk_get(dev, "ref");
1303 	if (IS_ERR(tc->refclk)) {
1304 		ret = PTR_ERR(tc->refclk);
1305 		dev_err(dev, "Failed to get refclk: %d\n", ret);
1306 		return ret;
1307 	}
1308 
1309 	tc->regmap = devm_regmap_init_i2c(client, &tc_regmap_config);
1310 	if (IS_ERR(tc->regmap)) {
1311 		ret = PTR_ERR(tc->regmap);
1312 		dev_err(dev, "Failed to initialize regmap: %d\n", ret);
1313 		return ret;
1314 	}
1315 
1316 	ret = regmap_read(tc->regmap, TC_IDREG, &tc->rev);
1317 	if (ret) {
1318 		dev_err(tc->dev, "can not read device ID: %d\n", ret);
1319 		return ret;
1320 	}
1321 
1322 	if ((tc->rev != 0x6601) && (tc->rev != 0x6603)) {
1323 		dev_err(tc->dev, "invalid device ID: 0x%08x\n", tc->rev);
1324 		return -EINVAL;
1325 	}
1326 
1327 	tc->assr = (tc->rev == 0x6601); /* Enable ASSR for eDP panels */
1328 
1329 	ret = tc_aux_link_setup(tc);
1330 	if (ret)
1331 		return ret;
1332 
1333 	/* Register DP AUX channel */
1334 	tc->aux.name = "TC358767 AUX i2c adapter";
1335 	tc->aux.dev = tc->dev;
1336 	tc->aux.transfer = tc_aux_transfer;
1337 	ret = drm_dp_aux_register(&tc->aux);
1338 	if (ret)
1339 		return ret;
1340 
1341 	ret = tc_get_display_props(tc);
1342 	if (ret)
1343 		goto err_unregister_aux;
1344 
1345 	tc_connector_set_polling(tc, &tc->connector);
1346 
1347 	tc->bridge.funcs = &tc_bridge_funcs;
1348 	tc->bridge.of_node = dev->of_node;
1349 	ret = drm_bridge_add(&tc->bridge);
1350 	if (ret) {
1351 		dev_err(dev, "Failed to add drm_bridge: %d\n", ret);
1352 		goto err_unregister_aux;
1353 	}
1354 
1355 	i2c_set_clientdata(client, tc);
1356 
1357 	return 0;
1358 err_unregister_aux:
1359 	drm_dp_aux_unregister(&tc->aux);
1360 	return ret;
1361 }
1362 
1363 static int tc_remove(struct i2c_client *client)
1364 {
1365 	struct tc_data *tc = i2c_get_clientdata(client);
1366 
1367 	drm_bridge_remove(&tc->bridge);
1368 	drm_dp_aux_unregister(&tc->aux);
1369 
1370 	tc_pxl_pll_dis(tc);
1371 
1372 	return 0;
1373 }
1374 
1375 static const struct i2c_device_id tc358767_i2c_ids[] = {
1376 	{ "tc358767", 0 },
1377 	{ }
1378 };
1379 MODULE_DEVICE_TABLE(i2c, tc358767_i2c_ids);
1380 
1381 static const struct of_device_id tc358767_of_ids[] = {
1382 	{ .compatible = "toshiba,tc358767", },
1383 	{ }
1384 };
1385 MODULE_DEVICE_TABLE(of, tc358767_of_ids);
1386 
1387 static struct i2c_driver tc358767_driver = {
1388 	.driver = {
1389 		.name = "tc358767",
1390 		.of_match_table = tc358767_of_ids,
1391 	},
1392 	.id_table = tc358767_i2c_ids,
1393 	.probe = tc_probe,
1394 	.remove	= tc_remove,
1395 };
1396 module_i2c_driver(tc358767_driver);
1397 
1398 MODULE_AUTHOR("Andrey Gusakov <andrey.gusakov@cogentembedded.com>");
1399 MODULE_DESCRIPTION("tc358767 eDP encoder driver");
1400 MODULE_LICENSE("GPL");
1401