xref: /openbmc/linux/drivers/gpu/drm/bridge/tc358767.c (revision 2fb658a6)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * tc358767 eDP bridge driver
4  *
5  * Copyright (C) 2016 CogentEmbedded Inc
6  * Author: Andrey Gusakov <andrey.gusakov@cogentembedded.com>
7  *
8  * Copyright (C) 2016 Pengutronix, Philipp Zabel <p.zabel@pengutronix.de>
9  *
10  * Copyright (C) 2016 Zodiac Inflight Innovations
11  *
12  * Initially based on: drivers/gpu/drm/i2c/tda998x_drv.c
13  *
14  * Copyright (C) 2012 Texas Instruments
15  * Author: Rob Clark <robdclark@gmail.com>
16  */
17 
18 #include <linux/bitfield.h>
19 #include <linux/clk.h>
20 #include <linux/device.h>
21 #include <linux/gpio/consumer.h>
22 #include <linux/i2c.h>
23 #include <linux/kernel.h>
24 #include <linux/module.h>
25 #include <linux/regmap.h>
26 #include <linux/slab.h>
27 
28 #include <drm/drm_atomic_helper.h>
29 #include <drm/drm_bridge.h>
30 #include <drm/drm_dp_helper.h>
31 #include <drm/drm_edid.h>
32 #include <drm/drm_of.h>
33 #include <drm/drm_panel.h>
34 #include <drm/drm_probe_helper.h>
35 
36 /* Registers */
37 
38 /* Display Parallel Interface */
39 #define DPIPXLFMT		0x0440
40 #define VS_POL_ACTIVE_LOW		(1 << 10)
41 #define HS_POL_ACTIVE_LOW		(1 << 9)
42 #define DE_POL_ACTIVE_HIGH		(0 << 8)
43 #define SUB_CFG_TYPE_CONFIG1		(0 << 2) /* LSB aligned */
44 #define SUB_CFG_TYPE_CONFIG2		(1 << 2) /* Loosely Packed */
45 #define SUB_CFG_TYPE_CONFIG3		(2 << 2) /* LSB aligned 8-bit */
46 #define DPI_BPP_RGB888			(0 << 0)
47 #define DPI_BPP_RGB666			(1 << 0)
48 #define DPI_BPP_RGB565			(2 << 0)
49 
50 /* Video Path */
51 #define VPCTRL0			0x0450
52 #define VSDELAY			GENMASK(31, 20)
53 #define OPXLFMT_RGB666			(0 << 8)
54 #define OPXLFMT_RGB888			(1 << 8)
55 #define FRMSYNC_DISABLED		(0 << 4) /* Video Timing Gen Disabled */
56 #define FRMSYNC_ENABLED			(1 << 4) /* Video Timing Gen Enabled */
57 #define MSF_DISABLED			(0 << 0) /* Magic Square FRC disabled */
58 #define MSF_ENABLED			(1 << 0) /* Magic Square FRC enabled */
59 #define HTIM01			0x0454
60 #define HPW			GENMASK(8, 0)
61 #define HBPR			GENMASK(24, 16)
62 #define HTIM02			0x0458
63 #define HDISPR			GENMASK(10, 0)
64 #define HFPR			GENMASK(24, 16)
65 #define VTIM01			0x045c
66 #define VSPR			GENMASK(7, 0)
67 #define VBPR			GENMASK(23, 16)
68 #define VTIM02			0x0460
69 #define VFPR			GENMASK(23, 16)
70 #define VDISPR			GENMASK(10, 0)
71 #define VFUEN0			0x0464
72 #define VFUEN				BIT(0)   /* Video Frame Timing Upload */
73 
74 /* System */
75 #define TC_IDREG		0x0500
76 #define SYSSTAT			0x0508
77 #define SYSCTRL			0x0510
78 #define DP0_AUDSRC_NO_INPUT		(0 << 3)
79 #define DP0_AUDSRC_I2S_RX		(1 << 3)
80 #define DP0_VIDSRC_NO_INPUT		(0 << 0)
81 #define DP0_VIDSRC_DSI_RX		(1 << 0)
82 #define DP0_VIDSRC_DPI_RX		(2 << 0)
83 #define DP0_VIDSRC_COLOR_BAR		(3 << 0)
84 #define SYSRSTENB		0x050c
85 #define ENBI2C				(1 << 0)
86 #define ENBLCD0				(1 << 2)
87 #define ENBBM				(1 << 3)
88 #define ENBDSIRX			(1 << 4)
89 #define ENBREG				(1 << 5)
90 #define ENBHDCP				(1 << 8)
91 #define GPIOM			0x0540
92 #define GPIOC			0x0544
93 #define GPIOO			0x0548
94 #define GPIOI			0x054c
95 #define INTCTL_G		0x0560
96 #define INTSTS_G		0x0564
97 
98 #define INT_SYSERR		BIT(16)
99 #define INT_GPIO_H(x)		(1 << (x == 0 ? 2 : 10))
100 #define INT_GPIO_LC(x)		(1 << (x == 0 ? 3 : 11))
101 
102 #define INT_GP0_LCNT		0x0584
103 #define INT_GP1_LCNT		0x0588
104 
105 /* Control */
106 #define DP0CTL			0x0600
107 #define VID_MN_GEN			BIT(6)   /* Auto-generate M/N values */
108 #define EF_EN				BIT(5)   /* Enable Enhanced Framing */
109 #define VID_EN				BIT(1)   /* Video transmission enable */
110 #define DP_EN				BIT(0)   /* Enable DPTX function */
111 
112 /* Clocks */
113 #define DP0_VIDMNGEN0		0x0610
114 #define DP0_VIDMNGEN1		0x0614
115 #define DP0_VMNGENSTATUS	0x0618
116 
117 /* Main Channel */
118 #define DP0_SECSAMPLE		0x0640
119 #define DP0_VIDSYNCDELAY	0x0644
120 #define VID_SYNC_DLY		GENMASK(15, 0)
121 #define THRESH_DLY		GENMASK(31, 16)
122 
123 #define DP0_TOTALVAL		0x0648
124 #define H_TOTAL			GENMASK(15, 0)
125 #define V_TOTAL			GENMASK(31, 16)
126 #define DP0_STARTVAL		0x064c
127 #define H_START			GENMASK(15, 0)
128 #define V_START			GENMASK(31, 16)
129 #define DP0_ACTIVEVAL		0x0650
130 #define H_ACT			GENMASK(15, 0)
131 #define V_ACT			GENMASK(31, 16)
132 
133 #define DP0_SYNCVAL		0x0654
134 #define VS_WIDTH		GENMASK(30, 16)
135 #define HS_WIDTH		GENMASK(14, 0)
136 #define SYNCVAL_HS_POL_ACTIVE_LOW	(1 << 15)
137 #define SYNCVAL_VS_POL_ACTIVE_LOW	(1 << 31)
138 #define DP0_MISC		0x0658
139 #define TU_SIZE_RECOMMENDED		(63) /* LSCLK cycles per TU */
140 #define MAX_TU_SYMBOL		GENMASK(28, 23)
141 #define TU_SIZE			GENMASK(21, 16)
142 #define BPC_6				(0 << 5)
143 #define BPC_8				(1 << 5)
144 
145 /* AUX channel */
146 #define DP0_AUXCFG0		0x0660
147 #define DP0_AUXCFG0_BSIZE	GENMASK(11, 8)
148 #define DP0_AUXCFG0_ADDR_ONLY	BIT(4)
149 #define DP0_AUXCFG1		0x0664
150 #define AUX_RX_FILTER_EN		BIT(16)
151 
152 #define DP0_AUXADDR		0x0668
153 #define DP0_AUXWDATA(i)		(0x066c + (i) * 4)
154 #define DP0_AUXRDATA(i)		(0x067c + (i) * 4)
155 #define DP0_AUXSTATUS		0x068c
156 #define AUX_BYTES		GENMASK(15, 8)
157 #define AUX_STATUS		GENMASK(7, 4)
158 #define AUX_TIMEOUT		BIT(1)
159 #define AUX_BUSY		BIT(0)
160 #define DP0_AUXI2CADR		0x0698
161 
162 /* Link Training */
163 #define DP0_SRCCTRL		0x06a0
164 #define DP0_SRCCTRL_SCRMBLDIS		BIT(13)
165 #define DP0_SRCCTRL_EN810B		BIT(12)
166 #define DP0_SRCCTRL_NOTP		(0 << 8)
167 #define DP0_SRCCTRL_TP1			(1 << 8)
168 #define DP0_SRCCTRL_TP2			(2 << 8)
169 #define DP0_SRCCTRL_LANESKEW		BIT(7)
170 #define DP0_SRCCTRL_SSCG		BIT(3)
171 #define DP0_SRCCTRL_LANES_1		(0 << 2)
172 #define DP0_SRCCTRL_LANES_2		(1 << 2)
173 #define DP0_SRCCTRL_BW27		(1 << 1)
174 #define DP0_SRCCTRL_BW162		(0 << 1)
175 #define DP0_SRCCTRL_AUTOCORRECT		BIT(0)
176 #define DP0_LTSTAT		0x06d0
177 #define LT_LOOPDONE			BIT(13)
178 #define LT_STATUS_MASK			(0x1f << 8)
179 #define LT_CHANNEL1_EQ_BITS		(DP_CHANNEL_EQ_BITS << 4)
180 #define LT_INTERLANE_ALIGN_DONE		BIT(3)
181 #define LT_CHANNEL0_EQ_BITS		(DP_CHANNEL_EQ_BITS)
182 #define DP0_SNKLTCHGREQ		0x06d4
183 #define DP0_LTLOOPCTRL		0x06d8
184 #define DP0_SNKLTCTRL		0x06e4
185 
186 #define DP1_SRCCTRL		0x07a0
187 
188 /* PHY */
189 #define DP_PHY_CTRL		0x0800
190 #define DP_PHY_RST			BIT(28)  /* DP PHY Global Soft Reset */
191 #define BGREN				BIT(25)  /* AUX PHY BGR Enable */
192 #define PWR_SW_EN			BIT(24)  /* PHY Power Switch Enable */
193 #define PHY_M1_RST			BIT(12)  /* Reset PHY1 Main Channel */
194 #define PHY_RDY				BIT(16)  /* PHY Main Channels Ready */
195 #define PHY_M0_RST			BIT(8)   /* Reset PHY0 Main Channel */
196 #define PHY_2LANE			BIT(2)   /* PHY Enable 2 lanes */
197 #define PHY_A0_EN			BIT(1)   /* PHY Aux Channel0 Enable */
198 #define PHY_M0_EN			BIT(0)   /* PHY Main Channel0 Enable */
199 
200 /* PLL */
201 #define DP0_PLLCTRL		0x0900
202 #define DP1_PLLCTRL		0x0904	/* not defined in DS */
203 #define PXL_PLLCTRL		0x0908
204 #define PLLUPDATE			BIT(2)
205 #define PLLBYP				BIT(1)
206 #define PLLEN				BIT(0)
207 #define PXL_PLLPARAM		0x0914
208 #define IN_SEL_REFCLK			(0 << 14)
209 #define SYS_PLLPARAM		0x0918
210 #define REF_FREQ_38M4			(0 << 8) /* 38.4 MHz */
211 #define REF_FREQ_19M2			(1 << 8) /* 19.2 MHz */
212 #define REF_FREQ_26M			(2 << 8) /* 26 MHz */
213 #define REF_FREQ_13M			(3 << 8) /* 13 MHz */
214 #define SYSCLK_SEL_LSCLK		(0 << 4)
215 #define LSCLK_DIV_1			(0 << 0)
216 #define LSCLK_DIV_2			(1 << 0)
217 
218 /* Test & Debug */
219 #define TSTCTL			0x0a00
220 #define COLOR_R			GENMASK(31, 24)
221 #define COLOR_G			GENMASK(23, 16)
222 #define COLOR_B			GENMASK(15, 8)
223 #define ENI2CFILTER		BIT(4)
224 #define COLOR_BAR_MODE		GENMASK(1, 0)
225 #define COLOR_BAR_MODE_BARS	2
226 #define PLL_DBG			0x0a04
227 
228 static bool tc_test_pattern;
229 module_param_named(test, tc_test_pattern, bool, 0644);
230 
231 struct tc_edp_link {
232 	struct drm_dp_link	base;
233 	u8			assr;
234 	bool			scrambler_dis;
235 	bool			spread;
236 };
237 
238 struct tc_data {
239 	struct device		*dev;
240 	struct regmap		*regmap;
241 	struct drm_dp_aux	aux;
242 
243 	struct drm_bridge	bridge;
244 	struct drm_connector	connector;
245 	struct drm_panel	*panel;
246 
247 	/* link settings */
248 	struct tc_edp_link	link;
249 
250 	/* display edid */
251 	struct edid		*edid;
252 	/* current mode */
253 	struct drm_display_mode	mode;
254 
255 	u32			rev;
256 	u8			assr;
257 
258 	struct gpio_desc	*sd_gpio;
259 	struct gpio_desc	*reset_gpio;
260 	struct clk		*refclk;
261 
262 	/* do we have IRQ */
263 	bool			have_irq;
264 
265 	/* HPD pin number (0 or 1) or -ENODEV */
266 	int			hpd_pin;
267 };
268 
269 static inline struct tc_data *aux_to_tc(struct drm_dp_aux *a)
270 {
271 	return container_of(a, struct tc_data, aux);
272 }
273 
274 static inline struct tc_data *bridge_to_tc(struct drm_bridge *b)
275 {
276 	return container_of(b, struct tc_data, bridge);
277 }
278 
279 static inline struct tc_data *connector_to_tc(struct drm_connector *c)
280 {
281 	return container_of(c, struct tc_data, connector);
282 }
283 
284 static inline int tc_poll_timeout(struct tc_data *tc, unsigned int addr,
285 				  unsigned int cond_mask,
286 				  unsigned int cond_value,
287 				  unsigned long sleep_us, u64 timeout_us)
288 {
289 	unsigned int val;
290 
291 	return regmap_read_poll_timeout(tc->regmap, addr, val,
292 					(val & cond_mask) == cond_value,
293 					sleep_us, timeout_us);
294 }
295 
296 static int tc_aux_wait_busy(struct tc_data *tc)
297 {
298 	return tc_poll_timeout(tc, DP0_AUXSTATUS, AUX_BUSY, 0, 1000, 100000);
299 }
300 
301 static int tc_aux_write_data(struct tc_data *tc, const void *data,
302 			     size_t size)
303 {
304 	u32 auxwdata[DP_AUX_MAX_PAYLOAD_BYTES / sizeof(u32)] = { 0 };
305 	int ret, count = ALIGN(size, sizeof(u32));
306 
307 	memcpy(auxwdata, data, size);
308 
309 	ret = regmap_raw_write(tc->regmap, DP0_AUXWDATA(0), auxwdata, count);
310 	if (ret)
311 		return ret;
312 
313 	return size;
314 }
315 
316 static int tc_aux_read_data(struct tc_data *tc, void *data, size_t size)
317 {
318 	u32 auxrdata[DP_AUX_MAX_PAYLOAD_BYTES / sizeof(u32)];
319 	int ret, count = ALIGN(size, sizeof(u32));
320 
321 	ret = regmap_raw_read(tc->regmap, DP0_AUXRDATA(0), auxrdata, count);
322 	if (ret)
323 		return ret;
324 
325 	memcpy(data, auxrdata, size);
326 
327 	return size;
328 }
329 
330 static u32 tc_auxcfg0(struct drm_dp_aux_msg *msg, size_t size)
331 {
332 	u32 auxcfg0 = msg->request;
333 
334 	if (size)
335 		auxcfg0 |= FIELD_PREP(DP0_AUXCFG0_BSIZE, size - 1);
336 	else
337 		auxcfg0 |= DP0_AUXCFG0_ADDR_ONLY;
338 
339 	return auxcfg0;
340 }
341 
342 static ssize_t tc_aux_transfer(struct drm_dp_aux *aux,
343 			       struct drm_dp_aux_msg *msg)
344 {
345 	struct tc_data *tc = aux_to_tc(aux);
346 	size_t size = min_t(size_t, DP_AUX_MAX_PAYLOAD_BYTES - 1, msg->size);
347 	u8 request = msg->request & ~DP_AUX_I2C_MOT;
348 	u32 auxstatus;
349 	int ret;
350 
351 	ret = tc_aux_wait_busy(tc);
352 	if (ret)
353 		return ret;
354 
355 	switch (request) {
356 	case DP_AUX_NATIVE_READ:
357 	case DP_AUX_I2C_READ:
358 		break;
359 	case DP_AUX_NATIVE_WRITE:
360 	case DP_AUX_I2C_WRITE:
361 		if (size) {
362 			ret = tc_aux_write_data(tc, msg->buffer, size);
363 			if (ret < 0)
364 				return ret;
365 		}
366 		break;
367 	default:
368 		return -EINVAL;
369 	}
370 
371 	/* Store address */
372 	ret = regmap_write(tc->regmap, DP0_AUXADDR, msg->address);
373 	if (ret)
374 		return ret;
375 	/* Start transfer */
376 	ret = regmap_write(tc->regmap, DP0_AUXCFG0, tc_auxcfg0(msg, size));
377 	if (ret)
378 		return ret;
379 
380 	ret = tc_aux_wait_busy(tc);
381 	if (ret)
382 		return ret;
383 
384 	ret = regmap_read(tc->regmap, DP0_AUXSTATUS, &auxstatus);
385 	if (ret)
386 		return ret;
387 
388 	if (auxstatus & AUX_TIMEOUT)
389 		return -ETIMEDOUT;
390 	/*
391 	 * For some reason address-only DP_AUX_I2C_WRITE (MOT), still
392 	 * reports 1 byte transferred in its status. To deal we that
393 	 * we ignore aux_bytes field if we know that this was an
394 	 * address-only transfer
395 	 */
396 	if (size)
397 		size = FIELD_GET(AUX_BYTES, auxstatus);
398 	msg->reply = FIELD_GET(AUX_STATUS, auxstatus);
399 
400 	switch (request) {
401 	case DP_AUX_NATIVE_READ:
402 	case DP_AUX_I2C_READ:
403 		if (size)
404 			return tc_aux_read_data(tc, msg->buffer, size);
405 		break;
406 	}
407 
408 	return size;
409 }
410 
411 static const char * const training_pattern1_errors[] = {
412 	"No errors",
413 	"Aux write error",
414 	"Aux read error",
415 	"Max voltage reached error",
416 	"Loop counter expired error",
417 	"res", "res", "res"
418 };
419 
420 static const char * const training_pattern2_errors[] = {
421 	"No errors",
422 	"Aux write error",
423 	"Aux read error",
424 	"Clock recovery failed error",
425 	"Loop counter expired error",
426 	"res", "res", "res"
427 };
428 
429 static u32 tc_srcctrl(struct tc_data *tc)
430 {
431 	/*
432 	 * No training pattern, skew lane 1 data by two LSCLK cycles with
433 	 * respect to lane 0 data, AutoCorrect Mode = 0
434 	 */
435 	u32 reg = DP0_SRCCTRL_NOTP | DP0_SRCCTRL_LANESKEW | DP0_SRCCTRL_EN810B;
436 
437 	if (tc->link.scrambler_dis)
438 		reg |= DP0_SRCCTRL_SCRMBLDIS;	/* Scrambler Disabled */
439 	if (tc->link.spread)
440 		reg |= DP0_SRCCTRL_SSCG;	/* Spread Spectrum Enable */
441 	if (tc->link.base.num_lanes == 2)
442 		reg |= DP0_SRCCTRL_LANES_2;	/* Two Main Channel Lanes */
443 	if (tc->link.base.rate != 162000)
444 		reg |= DP0_SRCCTRL_BW27;	/* 2.7 Gbps link */
445 	return reg;
446 }
447 
448 static int tc_pllupdate(struct tc_data *tc, unsigned int pllctrl)
449 {
450 	int ret;
451 
452 	ret = regmap_write(tc->regmap, pllctrl, PLLUPDATE | PLLEN);
453 	if (ret)
454 		return ret;
455 
456 	/* Wait for PLL to lock: up to 2.09 ms, depending on refclk */
457 	usleep_range(3000, 6000);
458 
459 	return 0;
460 }
461 
462 static int tc_pxl_pll_en(struct tc_data *tc, u32 refclk, u32 pixelclock)
463 {
464 	int ret;
465 	int i_pre, best_pre = 1;
466 	int i_post, best_post = 1;
467 	int div, best_div = 1;
468 	int mul, best_mul = 1;
469 	int delta, best_delta;
470 	int ext_div[] = {1, 2, 3, 5, 7};
471 	int best_pixelclock = 0;
472 	int vco_hi = 0;
473 	u32 pxl_pllparam;
474 
475 	dev_dbg(tc->dev, "PLL: requested %d pixelclock, ref %d\n", pixelclock,
476 		refclk);
477 	best_delta = pixelclock;
478 	/* Loop over all possible ext_divs, skipping invalid configurations */
479 	for (i_pre = 0; i_pre < ARRAY_SIZE(ext_div); i_pre++) {
480 		/*
481 		 * refclk / ext_pre_div should be in the 1 to 200 MHz range.
482 		 * We don't allow any refclk > 200 MHz, only check lower bounds.
483 		 */
484 		if (refclk / ext_div[i_pre] < 1000000)
485 			continue;
486 		for (i_post = 0; i_post < ARRAY_SIZE(ext_div); i_post++) {
487 			for (div = 1; div <= 16; div++) {
488 				u32 clk;
489 				u64 tmp;
490 
491 				tmp = pixelclock * ext_div[i_pre] *
492 				      ext_div[i_post] * div;
493 				do_div(tmp, refclk);
494 				mul = tmp;
495 
496 				/* Check limits */
497 				if ((mul < 1) || (mul > 128))
498 					continue;
499 
500 				clk = (refclk / ext_div[i_pre] / div) * mul;
501 				/*
502 				 * refclk * mul / (ext_pre_div * pre_div)
503 				 * should be in the 150 to 650 MHz range
504 				 */
505 				if ((clk > 650000000) || (clk < 150000000))
506 					continue;
507 
508 				clk = clk / ext_div[i_post];
509 				delta = clk - pixelclock;
510 
511 				if (abs(delta) < abs(best_delta)) {
512 					best_pre = i_pre;
513 					best_post = i_post;
514 					best_div = div;
515 					best_mul = mul;
516 					best_delta = delta;
517 					best_pixelclock = clk;
518 				}
519 			}
520 		}
521 	}
522 	if (best_pixelclock == 0) {
523 		dev_err(tc->dev, "Failed to calc clock for %d pixelclock\n",
524 			pixelclock);
525 		return -EINVAL;
526 	}
527 
528 	dev_dbg(tc->dev, "PLL: got %d, delta %d\n", best_pixelclock,
529 		best_delta);
530 	dev_dbg(tc->dev, "PLL: %d / %d / %d * %d / %d\n", refclk,
531 		ext_div[best_pre], best_div, best_mul, ext_div[best_post]);
532 
533 	/* if VCO >= 300 MHz */
534 	if (refclk / ext_div[best_pre] / best_div * best_mul >= 300000000)
535 		vco_hi = 1;
536 	/* see DS */
537 	if (best_div == 16)
538 		best_div = 0;
539 	if (best_mul == 128)
540 		best_mul = 0;
541 
542 	/* Power up PLL and switch to bypass */
543 	ret = regmap_write(tc->regmap, PXL_PLLCTRL, PLLBYP | PLLEN);
544 	if (ret)
545 		return ret;
546 
547 	pxl_pllparam  = vco_hi << 24; /* For PLL VCO >= 300 MHz = 1 */
548 	pxl_pllparam |= ext_div[best_pre] << 20; /* External Pre-divider */
549 	pxl_pllparam |= ext_div[best_post] << 16; /* External Post-divider */
550 	pxl_pllparam |= IN_SEL_REFCLK; /* Use RefClk as PLL input */
551 	pxl_pllparam |= best_div << 8; /* Divider for PLL RefClk */
552 	pxl_pllparam |= best_mul; /* Multiplier for PLL */
553 
554 	ret = regmap_write(tc->regmap, PXL_PLLPARAM, pxl_pllparam);
555 	if (ret)
556 		return ret;
557 
558 	/* Force PLL parameter update and disable bypass */
559 	return tc_pllupdate(tc, PXL_PLLCTRL);
560 }
561 
562 static int tc_pxl_pll_dis(struct tc_data *tc)
563 {
564 	/* Enable PLL bypass, power down PLL */
565 	return regmap_write(tc->regmap, PXL_PLLCTRL, PLLBYP);
566 }
567 
568 static int tc_stream_clock_calc(struct tc_data *tc)
569 {
570 	/*
571 	 * If the Stream clock and Link Symbol clock are
572 	 * asynchronous with each other, the value of M changes over
573 	 * time. This way of generating link clock and stream
574 	 * clock is called Asynchronous Clock mode. The value M
575 	 * must change while the value N stays constant. The
576 	 * value of N in this Asynchronous Clock mode must be set
577 	 * to 2^15 or 32,768.
578 	 *
579 	 * LSCLK = 1/10 of high speed link clock
580 	 *
581 	 * f_STRMCLK = M/N * f_LSCLK
582 	 * M/N = f_STRMCLK / f_LSCLK
583 	 *
584 	 */
585 	return regmap_write(tc->regmap, DP0_VIDMNGEN1, 32768);
586 }
587 
588 static int tc_set_syspllparam(struct tc_data *tc)
589 {
590 	unsigned long rate;
591 	u32 pllparam = SYSCLK_SEL_LSCLK | LSCLK_DIV_2;
592 
593 	rate = clk_get_rate(tc->refclk);
594 	switch (rate) {
595 	case 38400000:
596 		pllparam |= REF_FREQ_38M4;
597 		break;
598 	case 26000000:
599 		pllparam |= REF_FREQ_26M;
600 		break;
601 	case 19200000:
602 		pllparam |= REF_FREQ_19M2;
603 		break;
604 	case 13000000:
605 		pllparam |= REF_FREQ_13M;
606 		break;
607 	default:
608 		dev_err(tc->dev, "Invalid refclk rate: %lu Hz\n", rate);
609 		return -EINVAL;
610 	}
611 
612 	return regmap_write(tc->regmap, SYS_PLLPARAM, pllparam);
613 }
614 
615 static int tc_aux_link_setup(struct tc_data *tc)
616 {
617 	int ret;
618 	u32 dp0_auxcfg1;
619 
620 	/* Setup DP-PHY / PLL */
621 	ret = tc_set_syspllparam(tc);
622 	if (ret)
623 		goto err;
624 
625 	ret = regmap_write(tc->regmap, DP_PHY_CTRL,
626 			   BGREN | PWR_SW_EN | PHY_A0_EN);
627 	if (ret)
628 		goto err;
629 	/*
630 	 * Initially PLLs are in bypass. Force PLL parameter update,
631 	 * disable PLL bypass, enable PLL
632 	 */
633 	ret = tc_pllupdate(tc, DP0_PLLCTRL);
634 	if (ret)
635 		goto err;
636 
637 	ret = tc_pllupdate(tc, DP1_PLLCTRL);
638 	if (ret)
639 		goto err;
640 
641 	ret = tc_poll_timeout(tc, DP_PHY_CTRL, PHY_RDY, PHY_RDY, 1, 1000);
642 	if (ret == -ETIMEDOUT) {
643 		dev_err(tc->dev, "Timeout waiting for PHY to become ready");
644 		return ret;
645 	} else if (ret) {
646 		goto err;
647 	}
648 
649 	/* Setup AUX link */
650 	dp0_auxcfg1  = AUX_RX_FILTER_EN;
651 	dp0_auxcfg1 |= 0x06 << 8; /* Aux Bit Period Calculator Threshold */
652 	dp0_auxcfg1 |= 0x3f << 0; /* Aux Response Timeout Timer */
653 
654 	ret = regmap_write(tc->regmap, DP0_AUXCFG1, dp0_auxcfg1);
655 	if (ret)
656 		goto err;
657 
658 	return 0;
659 err:
660 	dev_err(tc->dev, "tc_aux_link_setup failed: %d\n", ret);
661 	return ret;
662 }
663 
664 static int tc_get_display_props(struct tc_data *tc)
665 {
666 	int ret;
667 	u8 reg;
668 
669 	/* Read DP Rx Link Capability */
670 	ret = drm_dp_link_probe(&tc->aux, &tc->link.base);
671 	if (ret < 0)
672 		goto err_dpcd_read;
673 	if (tc->link.base.rate != 162000 && tc->link.base.rate != 270000) {
674 		dev_dbg(tc->dev, "Falling to 2.7 Gbps rate\n");
675 		tc->link.base.rate = 270000;
676 	}
677 
678 	if (tc->link.base.num_lanes > 2) {
679 		dev_dbg(tc->dev, "Falling to 2 lanes\n");
680 		tc->link.base.num_lanes = 2;
681 	}
682 
683 	ret = drm_dp_dpcd_readb(&tc->aux, DP_MAX_DOWNSPREAD, &reg);
684 	if (ret < 0)
685 		goto err_dpcd_read;
686 	tc->link.spread = reg & DP_MAX_DOWNSPREAD_0_5;
687 
688 	ret = drm_dp_dpcd_readb(&tc->aux, DP_MAIN_LINK_CHANNEL_CODING, &reg);
689 	if (ret < 0)
690 		goto err_dpcd_read;
691 
692 	tc->link.scrambler_dis = false;
693 	/* read assr */
694 	ret = drm_dp_dpcd_readb(&tc->aux, DP_EDP_CONFIGURATION_SET, &reg);
695 	if (ret < 0)
696 		goto err_dpcd_read;
697 	tc->link.assr = reg & DP_ALTERNATE_SCRAMBLER_RESET_ENABLE;
698 
699 	dev_dbg(tc->dev, "DPCD rev: %d.%d, rate: %s, lanes: %d, framing: %s\n",
700 		tc->link.base.revision >> 4, tc->link.base.revision & 0x0f,
701 		(tc->link.base.rate == 162000) ? "1.62Gbps" : "2.7Gbps",
702 		tc->link.base.num_lanes,
703 		(tc->link.base.capabilities & DP_LINK_CAP_ENHANCED_FRAMING) ?
704 		"enhanced" : "non-enhanced");
705 	dev_dbg(tc->dev, "Downspread: %s, scrambler: %s\n",
706 		tc->link.spread ? "0.5%" : "0.0%",
707 		tc->link.scrambler_dis ? "disabled" : "enabled");
708 	dev_dbg(tc->dev, "Display ASSR: %d, TC358767 ASSR: %d\n",
709 		tc->link.assr, tc->assr);
710 
711 	return 0;
712 
713 err_dpcd_read:
714 	dev_err(tc->dev, "failed to read DPCD: %d\n", ret);
715 	return ret;
716 }
717 
718 static int tc_set_video_mode(struct tc_data *tc,
719 			     const struct drm_display_mode *mode)
720 {
721 	int ret;
722 	int vid_sync_dly;
723 	int max_tu_symbol;
724 
725 	int left_margin = mode->htotal - mode->hsync_end;
726 	int right_margin = mode->hsync_start - mode->hdisplay;
727 	int hsync_len = mode->hsync_end - mode->hsync_start;
728 	int upper_margin = mode->vtotal - mode->vsync_end;
729 	int lower_margin = mode->vsync_start - mode->vdisplay;
730 	int vsync_len = mode->vsync_end - mode->vsync_start;
731 	u32 dp0_syncval;
732 
733 	/*
734 	 * Recommended maximum number of symbols transferred in a transfer unit:
735 	 * DIV_ROUND_UP((input active video bandwidth in bytes) * tu_size,
736 	 *              (output active video bandwidth in bytes))
737 	 * Must be less than tu_size.
738 	 */
739 	max_tu_symbol = TU_SIZE_RECOMMENDED - 1;
740 
741 	dev_dbg(tc->dev, "set mode %dx%d\n",
742 		mode->hdisplay, mode->vdisplay);
743 	dev_dbg(tc->dev, "H margin %d,%d sync %d\n",
744 		left_margin, right_margin, hsync_len);
745 	dev_dbg(tc->dev, "V margin %d,%d sync %d\n",
746 		upper_margin, lower_margin, vsync_len);
747 	dev_dbg(tc->dev, "total: %dx%d\n", mode->htotal, mode->vtotal);
748 
749 
750 	/*
751 	 * LCD Ctl Frame Size
752 	 * datasheet is not clear of vsdelay in case of DPI
753 	 * assume we do not need any delay when DPI is a source of
754 	 * sync signals
755 	 */
756 	ret = regmap_write(tc->regmap, VPCTRL0,
757 			   FIELD_PREP(VSDELAY, 0) |
758 			   OPXLFMT_RGB888 | FRMSYNC_DISABLED | MSF_DISABLED);
759 	if (ret)
760 		return ret;
761 
762 	ret = regmap_write(tc->regmap, HTIM01,
763 			   FIELD_PREP(HBPR, ALIGN(left_margin, 2)) |
764 			   FIELD_PREP(HPW, ALIGN(hsync_len, 2)));
765 	if (ret)
766 		return ret;
767 
768 	ret = regmap_write(tc->regmap, HTIM02,
769 			   FIELD_PREP(HDISPR, ALIGN(mode->hdisplay, 2)) |
770 			   FIELD_PREP(HFPR, ALIGN(right_margin, 2)));
771 	if (ret)
772 		return ret;
773 
774 	ret = regmap_write(tc->regmap, VTIM01,
775 			   FIELD_PREP(VBPR, upper_margin) |
776 			   FIELD_PREP(VSPR, vsync_len));
777 	if (ret)
778 		return ret;
779 
780 	ret = regmap_write(tc->regmap, VTIM02,
781 			   FIELD_PREP(VFPR, lower_margin) |
782 			   FIELD_PREP(VDISPR, mode->vdisplay));
783 	if (ret)
784 		return ret;
785 
786 	ret = regmap_write(tc->regmap, VFUEN0, VFUEN); /* update settings */
787 	if (ret)
788 		return ret;
789 
790 	/* Test pattern settings */
791 	ret = regmap_write(tc->regmap, TSTCTL,
792 			   FIELD_PREP(COLOR_R, 120) |
793 			   FIELD_PREP(COLOR_G, 20) |
794 			   FIELD_PREP(COLOR_B, 99) |
795 			   ENI2CFILTER |
796 			   FIELD_PREP(COLOR_BAR_MODE, COLOR_BAR_MODE_BARS));
797 	if (ret)
798 		return ret;
799 
800 	/* DP Main Stream Attributes */
801 	vid_sync_dly = hsync_len + left_margin + mode->hdisplay;
802 	ret = regmap_write(tc->regmap, DP0_VIDSYNCDELAY,
803 		 FIELD_PREP(THRESH_DLY, max_tu_symbol) |
804 		 FIELD_PREP(VID_SYNC_DLY, vid_sync_dly));
805 
806 	ret = regmap_write(tc->regmap, DP0_TOTALVAL,
807 			   FIELD_PREP(H_TOTAL, mode->htotal) |
808 			   FIELD_PREP(V_TOTAL, mode->vtotal));
809 	if (ret)
810 		return ret;
811 
812 	ret = regmap_write(tc->regmap, DP0_STARTVAL,
813 			   FIELD_PREP(H_START, left_margin + hsync_len) |
814 			   FIELD_PREP(V_START, upper_margin + vsync_len));
815 	if (ret)
816 		return ret;
817 
818 	ret = regmap_write(tc->regmap, DP0_ACTIVEVAL,
819 			   FIELD_PREP(V_ACT, mode->vdisplay) |
820 			   FIELD_PREP(H_ACT, mode->hdisplay));
821 	if (ret)
822 		return ret;
823 
824 	dp0_syncval = FIELD_PREP(VS_WIDTH, vsync_len) |
825 		      FIELD_PREP(HS_WIDTH, hsync_len);
826 
827 	if (mode->flags & DRM_MODE_FLAG_NVSYNC)
828 		dp0_syncval |= SYNCVAL_VS_POL_ACTIVE_LOW;
829 
830 	if (mode->flags & DRM_MODE_FLAG_NHSYNC)
831 		dp0_syncval |= SYNCVAL_HS_POL_ACTIVE_LOW;
832 
833 	ret = regmap_write(tc->regmap, DP0_SYNCVAL, dp0_syncval);
834 	if (ret)
835 		return ret;
836 
837 	ret = regmap_write(tc->regmap, DPIPXLFMT,
838 			   VS_POL_ACTIVE_LOW | HS_POL_ACTIVE_LOW |
839 			   DE_POL_ACTIVE_HIGH | SUB_CFG_TYPE_CONFIG1 |
840 			   DPI_BPP_RGB888);
841 	if (ret)
842 		return ret;
843 
844 	ret = regmap_write(tc->regmap, DP0_MISC,
845 			   FIELD_PREP(MAX_TU_SYMBOL, max_tu_symbol) |
846 			   FIELD_PREP(TU_SIZE, TU_SIZE_RECOMMENDED) |
847 			   BPC_8);
848 	if (ret)
849 		return ret;
850 
851 	return 0;
852 }
853 
854 static int tc_wait_link_training(struct tc_data *tc)
855 {
856 	u32 value;
857 	int ret;
858 
859 	ret = tc_poll_timeout(tc, DP0_LTSTAT, LT_LOOPDONE,
860 			      LT_LOOPDONE, 1, 1000);
861 	if (ret) {
862 		dev_err(tc->dev, "Link training timeout waiting for LT_LOOPDONE!\n");
863 		return ret;
864 	}
865 
866 	ret = regmap_read(tc->regmap, DP0_LTSTAT, &value);
867 	if (ret)
868 		return ret;
869 
870 	return (value >> 8) & 0x7;
871 }
872 
873 static int tc_main_link_enable(struct tc_data *tc)
874 {
875 	struct drm_dp_aux *aux = &tc->aux;
876 	struct device *dev = tc->dev;
877 	u32 dp_phy_ctrl;
878 	u32 value;
879 	int ret;
880 	u8 tmp[DP_LINK_STATUS_SIZE];
881 
882 	dev_dbg(tc->dev, "link enable\n");
883 
884 	ret = regmap_read(tc->regmap, DP0CTL, &value);
885 	if (ret)
886 		return ret;
887 
888 	if (WARN_ON(value & DP_EN)) {
889 		ret = regmap_write(tc->regmap, DP0CTL, 0);
890 		if (ret)
891 			return ret;
892 	}
893 
894 	ret = regmap_write(tc->regmap, DP0_SRCCTRL, tc_srcctrl(tc));
895 	if (ret)
896 		return ret;
897 	/* SSCG and BW27 on DP1 must be set to the same as on DP0 */
898 	ret = regmap_write(tc->regmap, DP1_SRCCTRL,
899 		 (tc->link.spread ? DP0_SRCCTRL_SSCG : 0) |
900 		 ((tc->link.base.rate != 162000) ? DP0_SRCCTRL_BW27 : 0));
901 	if (ret)
902 		return ret;
903 
904 	ret = tc_set_syspllparam(tc);
905 	if (ret)
906 		return ret;
907 
908 	/* Setup Main Link */
909 	dp_phy_ctrl = BGREN | PWR_SW_EN | PHY_A0_EN | PHY_M0_EN;
910 	if (tc->link.base.num_lanes == 2)
911 		dp_phy_ctrl |= PHY_2LANE;
912 
913 	ret = regmap_write(tc->regmap, DP_PHY_CTRL, dp_phy_ctrl);
914 	if (ret)
915 		return ret;
916 
917 	/* PLL setup */
918 	ret = tc_pllupdate(tc, DP0_PLLCTRL);
919 	if (ret)
920 		return ret;
921 
922 	ret = tc_pllupdate(tc, DP1_PLLCTRL);
923 	if (ret)
924 		return ret;
925 
926 	/* Reset/Enable Main Links */
927 	dp_phy_ctrl |= DP_PHY_RST | PHY_M1_RST | PHY_M0_RST;
928 	ret = regmap_write(tc->regmap, DP_PHY_CTRL, dp_phy_ctrl);
929 	usleep_range(100, 200);
930 	dp_phy_ctrl &= ~(DP_PHY_RST | PHY_M1_RST | PHY_M0_RST);
931 	ret = regmap_write(tc->regmap, DP_PHY_CTRL, dp_phy_ctrl);
932 
933 	ret = tc_poll_timeout(tc, DP_PHY_CTRL, PHY_RDY, PHY_RDY, 1, 1000);
934 	if (ret) {
935 		dev_err(dev, "timeout waiting for phy become ready");
936 		return ret;
937 	}
938 
939 	/* Set misc: 8 bits per color */
940 	ret = regmap_update_bits(tc->regmap, DP0_MISC, BPC_8, BPC_8);
941 	if (ret)
942 		return ret;
943 
944 	/*
945 	 * ASSR mode
946 	 * on TC358767 side ASSR configured through strap pin
947 	 * seems there is no way to change this setting from SW
948 	 *
949 	 * check is tc configured for same mode
950 	 */
951 	if (tc->assr != tc->link.assr) {
952 		dev_dbg(dev, "Trying to set display to ASSR: %d\n",
953 			tc->assr);
954 		/* try to set ASSR on display side */
955 		tmp[0] = tc->assr;
956 		ret = drm_dp_dpcd_writeb(aux, DP_EDP_CONFIGURATION_SET, tmp[0]);
957 		if (ret < 0)
958 			goto err_dpcd_read;
959 		/* read back */
960 		ret = drm_dp_dpcd_readb(aux, DP_EDP_CONFIGURATION_SET, tmp);
961 		if (ret < 0)
962 			goto err_dpcd_read;
963 
964 		if (tmp[0] != tc->assr) {
965 			dev_dbg(dev, "Failed to switch display ASSR to %d, falling back to unscrambled mode\n",
966 				tc->assr);
967 			/* trying with disabled scrambler */
968 			tc->link.scrambler_dis = true;
969 		}
970 	}
971 
972 	/* Setup Link & DPRx Config for Training */
973 	ret = drm_dp_link_configure(aux, &tc->link.base);
974 	if (ret < 0)
975 		goto err_dpcd_write;
976 
977 	/* DOWNSPREAD_CTRL */
978 	tmp[0] = tc->link.spread ? DP_SPREAD_AMP_0_5 : 0x00;
979 	/* MAIN_LINK_CHANNEL_CODING_SET */
980 	tmp[1] =  DP_SET_ANSI_8B10B;
981 	ret = drm_dp_dpcd_write(aux, DP_DOWNSPREAD_CTRL, tmp, 2);
982 	if (ret < 0)
983 		goto err_dpcd_write;
984 
985 	/* Reset voltage-swing & pre-emphasis */
986 	tmp[0] = tmp[1] = DP_TRAIN_VOLTAGE_SWING_LEVEL_0 |
987 			  DP_TRAIN_PRE_EMPH_LEVEL_0;
988 	ret = drm_dp_dpcd_write(aux, DP_TRAINING_LANE0_SET, tmp, 2);
989 	if (ret < 0)
990 		goto err_dpcd_write;
991 
992 	/* Clock-Recovery */
993 
994 	/* Set DPCD 0x102 for Training Pattern 1 */
995 	ret = regmap_write(tc->regmap, DP0_SNKLTCTRL,
996 			   DP_LINK_SCRAMBLING_DISABLE |
997 			   DP_TRAINING_PATTERN_1);
998 	if (ret)
999 		return ret;
1000 
1001 	ret = regmap_write(tc->regmap, DP0_LTLOOPCTRL,
1002 			   (15 << 28) |	/* Defer Iteration Count */
1003 			   (15 << 24) |	/* Loop Iteration Count */
1004 			   (0xd << 0));	/* Loop Timer Delay */
1005 	if (ret)
1006 		return ret;
1007 
1008 	ret = regmap_write(tc->regmap, DP0_SRCCTRL,
1009 			   tc_srcctrl(tc) | DP0_SRCCTRL_SCRMBLDIS |
1010 			   DP0_SRCCTRL_AUTOCORRECT |
1011 			   DP0_SRCCTRL_TP1);
1012 	if (ret)
1013 		return ret;
1014 
1015 	/* Enable DP0 to start Link Training */
1016 	ret = regmap_write(tc->regmap, DP0CTL,
1017 			   ((tc->link.base.capabilities &
1018 			     DP_LINK_CAP_ENHANCED_FRAMING) ? EF_EN : 0) |
1019 			   DP_EN);
1020 	if (ret)
1021 		return ret;
1022 
1023 	/* wait */
1024 
1025 	ret = tc_wait_link_training(tc);
1026 	if (ret < 0)
1027 		return ret;
1028 
1029 	if (ret) {
1030 		dev_err(tc->dev, "Link training phase 1 failed: %s\n",
1031 			training_pattern1_errors[ret]);
1032 		return -ENODEV;
1033 	}
1034 
1035 	/* Channel Equalization */
1036 
1037 	/* Set DPCD 0x102 for Training Pattern 2 */
1038 	ret = regmap_write(tc->regmap, DP0_SNKLTCTRL,
1039 			   DP_LINK_SCRAMBLING_DISABLE |
1040 			   DP_TRAINING_PATTERN_2);
1041 	if (ret)
1042 		return ret;
1043 
1044 	ret = regmap_write(tc->regmap, DP0_SRCCTRL,
1045 			   tc_srcctrl(tc) | DP0_SRCCTRL_SCRMBLDIS |
1046 			   DP0_SRCCTRL_AUTOCORRECT |
1047 			   DP0_SRCCTRL_TP2);
1048 	if (ret)
1049 		return ret;
1050 
1051 	/* wait */
1052 	ret = tc_wait_link_training(tc);
1053 	if (ret < 0)
1054 		return ret;
1055 
1056 	if (ret) {
1057 		dev_err(tc->dev, "Link training phase 2 failed: %s\n",
1058 			training_pattern2_errors[ret]);
1059 		return -ENODEV;
1060 	}
1061 
1062 	/*
1063 	 * Toshiba's documentation suggests to first clear DPCD 0x102, then
1064 	 * clear the training pattern bit in DP0_SRCCTRL. Testing shows
1065 	 * that the link sometimes drops if those steps are done in that order,
1066 	 * but if the steps are done in reverse order, the link stays up.
1067 	 *
1068 	 * So we do the steps differently than documented here.
1069 	 */
1070 
1071 	/* Clear Training Pattern, set AutoCorrect Mode = 1 */
1072 	ret = regmap_write(tc->regmap, DP0_SRCCTRL, tc_srcctrl(tc) |
1073 			   DP0_SRCCTRL_AUTOCORRECT);
1074 	if (ret)
1075 		return ret;
1076 
1077 	/* Clear DPCD 0x102 */
1078 	/* Note: Can Not use DP0_SNKLTCTRL (0x06E4) short cut */
1079 	tmp[0] = tc->link.scrambler_dis ? DP_LINK_SCRAMBLING_DISABLE : 0x00;
1080 	ret = drm_dp_dpcd_writeb(aux, DP_TRAINING_PATTERN_SET, tmp[0]);
1081 	if (ret < 0)
1082 		goto err_dpcd_write;
1083 
1084 	/* Check link status */
1085 	ret = drm_dp_dpcd_read_link_status(aux, tmp);
1086 	if (ret < 0)
1087 		goto err_dpcd_read;
1088 
1089 	ret = 0;
1090 
1091 	value = tmp[0] & DP_CHANNEL_EQ_BITS;
1092 
1093 	if (value != DP_CHANNEL_EQ_BITS) {
1094 		dev_err(tc->dev, "Lane 0 failed: %x\n", value);
1095 		ret = -ENODEV;
1096 	}
1097 
1098 	if (tc->link.base.num_lanes == 2) {
1099 		value = (tmp[0] >> 4) & DP_CHANNEL_EQ_BITS;
1100 
1101 		if (value != DP_CHANNEL_EQ_BITS) {
1102 			dev_err(tc->dev, "Lane 1 failed: %x\n", value);
1103 			ret = -ENODEV;
1104 		}
1105 
1106 		if (!(tmp[2] & DP_INTERLANE_ALIGN_DONE)) {
1107 			dev_err(tc->dev, "Interlane align failed\n");
1108 			ret = -ENODEV;
1109 		}
1110 	}
1111 
1112 	if (ret) {
1113 		dev_err(dev, "0x0202 LANE0_1_STATUS:            0x%02x\n", tmp[0]);
1114 		dev_err(dev, "0x0203 LANE2_3_STATUS             0x%02x\n", tmp[1]);
1115 		dev_err(dev, "0x0204 LANE_ALIGN_STATUS_UPDATED: 0x%02x\n", tmp[2]);
1116 		dev_err(dev, "0x0205 SINK_STATUS:               0x%02x\n", tmp[3]);
1117 		dev_err(dev, "0x0206 ADJUST_REQUEST_LANE0_1:    0x%02x\n", tmp[4]);
1118 		dev_err(dev, "0x0207 ADJUST_REQUEST_LANE2_3:    0x%02x\n", tmp[5]);
1119 		return ret;
1120 	}
1121 
1122 	return 0;
1123 err_dpcd_read:
1124 	dev_err(tc->dev, "Failed to read DPCD: %d\n", ret);
1125 	return ret;
1126 err_dpcd_write:
1127 	dev_err(tc->dev, "Failed to write DPCD: %d\n", ret);
1128 	return ret;
1129 }
1130 
1131 static int tc_main_link_disable(struct tc_data *tc)
1132 {
1133 	int ret;
1134 
1135 	dev_dbg(tc->dev, "link disable\n");
1136 
1137 	ret = regmap_write(tc->regmap, DP0_SRCCTRL, 0);
1138 	if (ret)
1139 		return ret;
1140 
1141 	return regmap_write(tc->regmap, DP0CTL, 0);
1142 }
1143 
1144 static int tc_stream_enable(struct tc_data *tc)
1145 {
1146 	int ret;
1147 	u32 value;
1148 
1149 	dev_dbg(tc->dev, "enable video stream\n");
1150 
1151 	/* PXL PLL setup */
1152 	if (tc_test_pattern) {
1153 		ret = tc_pxl_pll_en(tc, clk_get_rate(tc->refclk),
1154 				    1000 * tc->mode.clock);
1155 		if (ret)
1156 			return ret;
1157 	}
1158 
1159 	ret = tc_set_video_mode(tc, &tc->mode);
1160 	if (ret)
1161 		return ret;
1162 
1163 	/* Set M/N */
1164 	ret = tc_stream_clock_calc(tc);
1165 	if (ret)
1166 		return ret;
1167 
1168 	value = VID_MN_GEN | DP_EN;
1169 	if (tc->link.base.capabilities & DP_LINK_CAP_ENHANCED_FRAMING)
1170 		value |= EF_EN;
1171 	ret = regmap_write(tc->regmap, DP0CTL, value);
1172 	if (ret)
1173 		return ret;
1174 	/*
1175 	 * VID_EN assertion should be delayed by at least N * LSCLK
1176 	 * cycles from the time VID_MN_GEN is enabled in order to
1177 	 * generate stable values for VID_M. LSCLK is 270 MHz or
1178 	 * 162 MHz, VID_N is set to 32768 in  tc_stream_clock_calc(),
1179 	 * so a delay of at least 203 us should suffice.
1180 	 */
1181 	usleep_range(500, 1000);
1182 	value |= VID_EN;
1183 	ret = regmap_write(tc->regmap, DP0CTL, value);
1184 	if (ret)
1185 		return ret;
1186 	/* Set input interface */
1187 	value = DP0_AUDSRC_NO_INPUT;
1188 	if (tc_test_pattern)
1189 		value |= DP0_VIDSRC_COLOR_BAR;
1190 	else
1191 		value |= DP0_VIDSRC_DPI_RX;
1192 	ret = regmap_write(tc->regmap, SYSCTRL, value);
1193 	if (ret)
1194 		return ret;
1195 
1196 	return 0;
1197 }
1198 
1199 static int tc_stream_disable(struct tc_data *tc)
1200 {
1201 	int ret;
1202 
1203 	dev_dbg(tc->dev, "disable video stream\n");
1204 
1205 	ret = regmap_update_bits(tc->regmap, DP0CTL, VID_EN, 0);
1206 	if (ret)
1207 		return ret;
1208 
1209 	tc_pxl_pll_dis(tc);
1210 
1211 	return 0;
1212 }
1213 
1214 static void tc_bridge_pre_enable(struct drm_bridge *bridge)
1215 {
1216 	struct tc_data *tc = bridge_to_tc(bridge);
1217 
1218 	drm_panel_prepare(tc->panel);
1219 }
1220 
1221 static void tc_bridge_enable(struct drm_bridge *bridge)
1222 {
1223 	struct tc_data *tc = bridge_to_tc(bridge);
1224 	int ret;
1225 
1226 	ret = tc_get_display_props(tc);
1227 	if (ret < 0) {
1228 		dev_err(tc->dev, "failed to read display props: %d\n", ret);
1229 		return;
1230 	}
1231 
1232 	ret = tc_main_link_enable(tc);
1233 	if (ret < 0) {
1234 		dev_err(tc->dev, "main link enable error: %d\n", ret);
1235 		return;
1236 	}
1237 
1238 	ret = tc_stream_enable(tc);
1239 	if (ret < 0) {
1240 		dev_err(tc->dev, "main link stream start error: %d\n", ret);
1241 		tc_main_link_disable(tc);
1242 		return;
1243 	}
1244 
1245 	drm_panel_enable(tc->panel);
1246 }
1247 
1248 static void tc_bridge_disable(struct drm_bridge *bridge)
1249 {
1250 	struct tc_data *tc = bridge_to_tc(bridge);
1251 	int ret;
1252 
1253 	drm_panel_disable(tc->panel);
1254 
1255 	ret = tc_stream_disable(tc);
1256 	if (ret < 0)
1257 		dev_err(tc->dev, "main link stream stop error: %d\n", ret);
1258 
1259 	ret = tc_main_link_disable(tc);
1260 	if (ret < 0)
1261 		dev_err(tc->dev, "main link disable error: %d\n", ret);
1262 }
1263 
1264 static void tc_bridge_post_disable(struct drm_bridge *bridge)
1265 {
1266 	struct tc_data *tc = bridge_to_tc(bridge);
1267 
1268 	drm_panel_unprepare(tc->panel);
1269 }
1270 
1271 static bool tc_bridge_mode_fixup(struct drm_bridge *bridge,
1272 				 const struct drm_display_mode *mode,
1273 				 struct drm_display_mode *adj)
1274 {
1275 	/* Fixup sync polarities, both hsync and vsync are active low */
1276 	adj->flags = mode->flags;
1277 	adj->flags |= (DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC);
1278 	adj->flags &= ~(DRM_MODE_FLAG_PHSYNC | DRM_MODE_FLAG_PVSYNC);
1279 
1280 	return true;
1281 }
1282 
1283 static enum drm_mode_status tc_mode_valid(struct drm_bridge *bridge,
1284 					  const struct drm_display_mode *mode)
1285 {
1286 	struct tc_data *tc = bridge_to_tc(bridge);
1287 	u32 req, avail;
1288 	u32 bits_per_pixel = 24;
1289 
1290 	/* DPI interface clock limitation: upto 154 MHz */
1291 	if (mode->clock > 154000)
1292 		return MODE_CLOCK_HIGH;
1293 
1294 	req = mode->clock * bits_per_pixel / 8;
1295 	avail = tc->link.base.num_lanes * tc->link.base.rate;
1296 
1297 	if (req > avail)
1298 		return MODE_BAD;
1299 
1300 	return MODE_OK;
1301 }
1302 
1303 static void tc_bridge_mode_set(struct drm_bridge *bridge,
1304 			       const struct drm_display_mode *mode,
1305 			       const struct drm_display_mode *adj)
1306 {
1307 	struct tc_data *tc = bridge_to_tc(bridge);
1308 
1309 	tc->mode = *mode;
1310 }
1311 
1312 static int tc_connector_get_modes(struct drm_connector *connector)
1313 {
1314 	struct tc_data *tc = connector_to_tc(connector);
1315 	struct edid *edid;
1316 	int count;
1317 	int ret;
1318 
1319 	ret = tc_get_display_props(tc);
1320 	if (ret < 0) {
1321 		dev_err(tc->dev, "failed to read display props: %d\n", ret);
1322 		return 0;
1323 	}
1324 
1325 	count = drm_panel_get_modes(tc->panel);
1326 	if (count > 0)
1327 		return count;
1328 
1329 	edid = drm_get_edid(connector, &tc->aux.ddc);
1330 
1331 	kfree(tc->edid);
1332 	tc->edid = edid;
1333 	if (!edid)
1334 		return 0;
1335 
1336 	drm_connector_update_edid_property(connector, edid);
1337 	count = drm_add_edid_modes(connector, edid);
1338 
1339 	return count;
1340 }
1341 
1342 static const struct drm_connector_helper_funcs tc_connector_helper_funcs = {
1343 	.get_modes = tc_connector_get_modes,
1344 };
1345 
1346 static enum drm_connector_status tc_connector_detect(struct drm_connector *connector,
1347 						     bool force)
1348 {
1349 	struct tc_data *tc = connector_to_tc(connector);
1350 	bool conn;
1351 	u32 val;
1352 	int ret;
1353 
1354 	if (tc->hpd_pin < 0) {
1355 		if (tc->panel)
1356 			return connector_status_connected;
1357 		else
1358 			return connector_status_unknown;
1359 	}
1360 
1361 	ret = regmap_read(tc->regmap, GPIOI, &val);
1362 	if (ret)
1363 		return connector_status_unknown;
1364 
1365 	conn = val & BIT(tc->hpd_pin);
1366 
1367 	if (conn)
1368 		return connector_status_connected;
1369 	else
1370 		return connector_status_disconnected;
1371 }
1372 
1373 static const struct drm_connector_funcs tc_connector_funcs = {
1374 	.detect = tc_connector_detect,
1375 	.fill_modes = drm_helper_probe_single_connector_modes,
1376 	.destroy = drm_connector_cleanup,
1377 	.reset = drm_atomic_helper_connector_reset,
1378 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
1379 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
1380 };
1381 
1382 static int tc_bridge_attach(struct drm_bridge *bridge)
1383 {
1384 	u32 bus_format = MEDIA_BUS_FMT_RGB888_1X24;
1385 	struct tc_data *tc = bridge_to_tc(bridge);
1386 	struct drm_device *drm = bridge->dev;
1387 	int ret;
1388 
1389 	/* Create DP/eDP connector */
1390 	drm_connector_helper_add(&tc->connector, &tc_connector_helper_funcs);
1391 	ret = drm_connector_init(drm, &tc->connector, &tc_connector_funcs,
1392 				 tc->panel ? DRM_MODE_CONNECTOR_eDP :
1393 				 DRM_MODE_CONNECTOR_DisplayPort);
1394 	if (ret)
1395 		return ret;
1396 
1397 	/* Don't poll if don't have HPD connected */
1398 	if (tc->hpd_pin >= 0) {
1399 		if (tc->have_irq)
1400 			tc->connector.polled = DRM_CONNECTOR_POLL_HPD;
1401 		else
1402 			tc->connector.polled = DRM_CONNECTOR_POLL_CONNECT |
1403 					       DRM_CONNECTOR_POLL_DISCONNECT;
1404 	}
1405 
1406 	if (tc->panel)
1407 		drm_panel_attach(tc->panel, &tc->connector);
1408 
1409 	drm_display_info_set_bus_formats(&tc->connector.display_info,
1410 					 &bus_format, 1);
1411 	tc->connector.display_info.bus_flags =
1412 		DRM_BUS_FLAG_DE_HIGH |
1413 		DRM_BUS_FLAG_PIXDATA_DRIVE_NEGEDGE |
1414 		DRM_BUS_FLAG_SYNC_DRIVE_NEGEDGE;
1415 	drm_connector_attach_encoder(&tc->connector, tc->bridge.encoder);
1416 
1417 	return 0;
1418 }
1419 
1420 static const struct drm_bridge_funcs tc_bridge_funcs = {
1421 	.attach = tc_bridge_attach,
1422 	.mode_valid = tc_mode_valid,
1423 	.mode_set = tc_bridge_mode_set,
1424 	.pre_enable = tc_bridge_pre_enable,
1425 	.enable = tc_bridge_enable,
1426 	.disable = tc_bridge_disable,
1427 	.post_disable = tc_bridge_post_disable,
1428 	.mode_fixup = tc_bridge_mode_fixup,
1429 };
1430 
1431 static bool tc_readable_reg(struct device *dev, unsigned int reg)
1432 {
1433 	return reg != SYSCTRL;
1434 }
1435 
1436 static const struct regmap_range tc_volatile_ranges[] = {
1437 	regmap_reg_range(DP0_AUXWDATA(0), DP0_AUXSTATUS),
1438 	regmap_reg_range(DP0_LTSTAT, DP0_SNKLTCHGREQ),
1439 	regmap_reg_range(DP_PHY_CTRL, DP_PHY_CTRL),
1440 	regmap_reg_range(DP0_PLLCTRL, PXL_PLLCTRL),
1441 	regmap_reg_range(VFUEN0, VFUEN0),
1442 	regmap_reg_range(INTSTS_G, INTSTS_G),
1443 	regmap_reg_range(GPIOI, GPIOI),
1444 };
1445 
1446 static const struct regmap_access_table tc_volatile_table = {
1447 	.yes_ranges = tc_volatile_ranges,
1448 	.n_yes_ranges = ARRAY_SIZE(tc_volatile_ranges),
1449 };
1450 
1451 static bool tc_writeable_reg(struct device *dev, unsigned int reg)
1452 {
1453 	return (reg != TC_IDREG) &&
1454 	       (reg != DP0_LTSTAT) &&
1455 	       (reg != DP0_SNKLTCHGREQ);
1456 }
1457 
1458 static const struct regmap_config tc_regmap_config = {
1459 	.name = "tc358767",
1460 	.reg_bits = 16,
1461 	.val_bits = 32,
1462 	.reg_stride = 4,
1463 	.max_register = PLL_DBG,
1464 	.cache_type = REGCACHE_RBTREE,
1465 	.readable_reg = tc_readable_reg,
1466 	.volatile_table = &tc_volatile_table,
1467 	.writeable_reg = tc_writeable_reg,
1468 	.reg_format_endian = REGMAP_ENDIAN_BIG,
1469 	.val_format_endian = REGMAP_ENDIAN_LITTLE,
1470 };
1471 
1472 static irqreturn_t tc_irq_handler(int irq, void *arg)
1473 {
1474 	struct tc_data *tc = arg;
1475 	u32 val;
1476 	int r;
1477 
1478 	r = regmap_read(tc->regmap, INTSTS_G, &val);
1479 	if (r)
1480 		return IRQ_NONE;
1481 
1482 	if (!val)
1483 		return IRQ_NONE;
1484 
1485 	if (val & INT_SYSERR) {
1486 		u32 stat = 0;
1487 
1488 		regmap_read(tc->regmap, SYSSTAT, &stat);
1489 
1490 		dev_err(tc->dev, "syserr %x\n", stat);
1491 	}
1492 
1493 	if (tc->hpd_pin >= 0 && tc->bridge.dev) {
1494 		/*
1495 		 * H is triggered when the GPIO goes high.
1496 		 *
1497 		 * LC is triggered when the GPIO goes low and stays low for
1498 		 * the duration of LCNT
1499 		 */
1500 		bool h = val & INT_GPIO_H(tc->hpd_pin);
1501 		bool lc = val & INT_GPIO_LC(tc->hpd_pin);
1502 
1503 		dev_dbg(tc->dev, "GPIO%d: %s %s\n", tc->hpd_pin,
1504 			h ? "H" : "", lc ? "LC" : "");
1505 
1506 		if (h || lc)
1507 			drm_kms_helper_hotplug_event(tc->bridge.dev);
1508 	}
1509 
1510 	regmap_write(tc->regmap, INTSTS_G, val);
1511 
1512 	return IRQ_HANDLED;
1513 }
1514 
1515 static int tc_probe(struct i2c_client *client, const struct i2c_device_id *id)
1516 {
1517 	struct device *dev = &client->dev;
1518 	struct tc_data *tc;
1519 	int ret;
1520 
1521 	tc = devm_kzalloc(dev, sizeof(*tc), GFP_KERNEL);
1522 	if (!tc)
1523 		return -ENOMEM;
1524 
1525 	tc->dev = dev;
1526 
1527 	/* port@2 is the output port */
1528 	ret = drm_of_find_panel_or_bridge(dev->of_node, 2, 0, &tc->panel, NULL);
1529 	if (ret && ret != -ENODEV)
1530 		return ret;
1531 
1532 	/* Shut down GPIO is optional */
1533 	tc->sd_gpio = devm_gpiod_get_optional(dev, "shutdown", GPIOD_OUT_HIGH);
1534 	if (IS_ERR(tc->sd_gpio))
1535 		return PTR_ERR(tc->sd_gpio);
1536 
1537 	if (tc->sd_gpio) {
1538 		gpiod_set_value_cansleep(tc->sd_gpio, 0);
1539 		usleep_range(5000, 10000);
1540 	}
1541 
1542 	/* Reset GPIO is optional */
1543 	tc->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
1544 	if (IS_ERR(tc->reset_gpio))
1545 		return PTR_ERR(tc->reset_gpio);
1546 
1547 	if (tc->reset_gpio) {
1548 		gpiod_set_value_cansleep(tc->reset_gpio, 1);
1549 		usleep_range(5000, 10000);
1550 	}
1551 
1552 	tc->refclk = devm_clk_get(dev, "ref");
1553 	if (IS_ERR(tc->refclk)) {
1554 		ret = PTR_ERR(tc->refclk);
1555 		dev_err(dev, "Failed to get refclk: %d\n", ret);
1556 		return ret;
1557 	}
1558 
1559 	tc->regmap = devm_regmap_init_i2c(client, &tc_regmap_config);
1560 	if (IS_ERR(tc->regmap)) {
1561 		ret = PTR_ERR(tc->regmap);
1562 		dev_err(dev, "Failed to initialize regmap: %d\n", ret);
1563 		return ret;
1564 	}
1565 
1566 	ret = of_property_read_u32(dev->of_node, "toshiba,hpd-pin",
1567 				   &tc->hpd_pin);
1568 	if (ret) {
1569 		tc->hpd_pin = -ENODEV;
1570 	} else {
1571 		if (tc->hpd_pin < 0 || tc->hpd_pin > 1) {
1572 			dev_err(dev, "failed to parse HPD number\n");
1573 			return ret;
1574 		}
1575 	}
1576 
1577 	if (client->irq > 0) {
1578 		/* enable SysErr */
1579 		regmap_write(tc->regmap, INTCTL_G, INT_SYSERR);
1580 
1581 		ret = devm_request_threaded_irq(dev, client->irq,
1582 						NULL, tc_irq_handler,
1583 						IRQF_ONESHOT,
1584 						"tc358767-irq", tc);
1585 		if (ret) {
1586 			dev_err(dev, "failed to register dp interrupt\n");
1587 			return ret;
1588 		}
1589 
1590 		tc->have_irq = true;
1591 	}
1592 
1593 	ret = regmap_read(tc->regmap, TC_IDREG, &tc->rev);
1594 	if (ret) {
1595 		dev_err(tc->dev, "can not read device ID: %d\n", ret);
1596 		return ret;
1597 	}
1598 
1599 	if ((tc->rev != 0x6601) && (tc->rev != 0x6603)) {
1600 		dev_err(tc->dev, "invalid device ID: 0x%08x\n", tc->rev);
1601 		return -EINVAL;
1602 	}
1603 
1604 	tc->assr = (tc->rev == 0x6601); /* Enable ASSR for eDP panels */
1605 
1606 	if (!tc->reset_gpio) {
1607 		/*
1608 		 * If the reset pin isn't present, do a software reset. It isn't
1609 		 * as thorough as the hardware reset, as we can't reset the I2C
1610 		 * communication block for obvious reasons, but it's getting the
1611 		 * chip into a defined state.
1612 		 */
1613 		regmap_update_bits(tc->regmap, SYSRSTENB,
1614 				ENBLCD0 | ENBBM | ENBDSIRX | ENBREG | ENBHDCP,
1615 				0);
1616 		regmap_update_bits(tc->regmap, SYSRSTENB,
1617 				ENBLCD0 | ENBBM | ENBDSIRX | ENBREG | ENBHDCP,
1618 				ENBLCD0 | ENBBM | ENBDSIRX | ENBREG | ENBHDCP);
1619 		usleep_range(5000, 10000);
1620 	}
1621 
1622 	if (tc->hpd_pin >= 0) {
1623 		u32 lcnt_reg = tc->hpd_pin == 0 ? INT_GP0_LCNT : INT_GP1_LCNT;
1624 		u32 h_lc = INT_GPIO_H(tc->hpd_pin) | INT_GPIO_LC(tc->hpd_pin);
1625 
1626 		/* Set LCNT to 2ms */
1627 		regmap_write(tc->regmap, lcnt_reg,
1628 			     clk_get_rate(tc->refclk) * 2 / 1000);
1629 		/* We need the "alternate" mode for HPD */
1630 		regmap_write(tc->regmap, GPIOM, BIT(tc->hpd_pin));
1631 
1632 		if (tc->have_irq) {
1633 			/* enable H & LC */
1634 			regmap_update_bits(tc->regmap, INTCTL_G, h_lc, h_lc);
1635 		}
1636 	}
1637 
1638 	ret = tc_aux_link_setup(tc);
1639 	if (ret)
1640 		return ret;
1641 
1642 	/* Register DP AUX channel */
1643 	tc->aux.name = "TC358767 AUX i2c adapter";
1644 	tc->aux.dev = tc->dev;
1645 	tc->aux.transfer = tc_aux_transfer;
1646 	ret = drm_dp_aux_register(&tc->aux);
1647 	if (ret)
1648 		return ret;
1649 
1650 	tc->bridge.funcs = &tc_bridge_funcs;
1651 	tc->bridge.of_node = dev->of_node;
1652 	drm_bridge_add(&tc->bridge);
1653 
1654 	i2c_set_clientdata(client, tc);
1655 
1656 	return 0;
1657 }
1658 
1659 static int tc_remove(struct i2c_client *client)
1660 {
1661 	struct tc_data *tc = i2c_get_clientdata(client);
1662 
1663 	drm_bridge_remove(&tc->bridge);
1664 	drm_dp_aux_unregister(&tc->aux);
1665 
1666 	return 0;
1667 }
1668 
1669 static const struct i2c_device_id tc358767_i2c_ids[] = {
1670 	{ "tc358767", 0 },
1671 	{ }
1672 };
1673 MODULE_DEVICE_TABLE(i2c, tc358767_i2c_ids);
1674 
1675 static const struct of_device_id tc358767_of_ids[] = {
1676 	{ .compatible = "toshiba,tc358767", },
1677 	{ }
1678 };
1679 MODULE_DEVICE_TABLE(of, tc358767_of_ids);
1680 
1681 static struct i2c_driver tc358767_driver = {
1682 	.driver = {
1683 		.name = "tc358767",
1684 		.of_match_table = tc358767_of_ids,
1685 	},
1686 	.id_table = tc358767_i2c_ids,
1687 	.probe = tc_probe,
1688 	.remove	= tc_remove,
1689 };
1690 module_i2c_driver(tc358767_driver);
1691 
1692 MODULE_AUTHOR("Andrey Gusakov <andrey.gusakov@cogentembedded.com>");
1693 MODULE_DESCRIPTION("tc358767 eDP encoder driver");
1694 MODULE_LICENSE("GPL");
1695