xref: /openbmc/linux/drivers/gpu/drm/bridge/tc358767.c (revision 8622a0e5)
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 	u8			dpcd[DP_RECEIVER_CAP_SIZE];
233 	unsigned int		rate;
234 	u8			num_lanes;
235 	u8			assr;
236 	bool			scrambler_dis;
237 	bool			spread;
238 };
239 
240 struct tc_data {
241 	struct device		*dev;
242 	struct regmap		*regmap;
243 	struct drm_dp_aux	aux;
244 
245 	struct drm_bridge	bridge;
246 	struct drm_connector	connector;
247 	struct drm_panel	*panel;
248 
249 	/* link settings */
250 	struct tc_edp_link	link;
251 
252 	/* display edid */
253 	struct edid		*edid;
254 	/* current mode */
255 	struct drm_display_mode	mode;
256 
257 	u32			rev;
258 	u8			assr;
259 
260 	struct gpio_desc	*sd_gpio;
261 	struct gpio_desc	*reset_gpio;
262 	struct clk		*refclk;
263 
264 	/* do we have IRQ */
265 	bool			have_irq;
266 
267 	/* HPD pin number (0 or 1) or -ENODEV */
268 	int			hpd_pin;
269 };
270 
271 static inline struct tc_data *aux_to_tc(struct drm_dp_aux *a)
272 {
273 	return container_of(a, struct tc_data, aux);
274 }
275 
276 static inline struct tc_data *bridge_to_tc(struct drm_bridge *b)
277 {
278 	return container_of(b, struct tc_data, bridge);
279 }
280 
281 static inline struct tc_data *connector_to_tc(struct drm_connector *c)
282 {
283 	return container_of(c, struct tc_data, connector);
284 }
285 
286 static inline int tc_poll_timeout(struct tc_data *tc, unsigned int addr,
287 				  unsigned int cond_mask,
288 				  unsigned int cond_value,
289 				  unsigned long sleep_us, u64 timeout_us)
290 {
291 	unsigned int val;
292 
293 	return regmap_read_poll_timeout(tc->regmap, addr, val,
294 					(val & cond_mask) == cond_value,
295 					sleep_us, timeout_us);
296 }
297 
298 static int tc_aux_wait_busy(struct tc_data *tc)
299 {
300 	return tc_poll_timeout(tc, DP0_AUXSTATUS, AUX_BUSY, 0, 100, 100000);
301 }
302 
303 static int tc_aux_write_data(struct tc_data *tc, const void *data,
304 			     size_t size)
305 {
306 	u32 auxwdata[DP_AUX_MAX_PAYLOAD_BYTES / sizeof(u32)] = { 0 };
307 	int ret, count = ALIGN(size, sizeof(u32));
308 
309 	memcpy(auxwdata, data, size);
310 
311 	ret = regmap_raw_write(tc->regmap, DP0_AUXWDATA(0), auxwdata, count);
312 	if (ret)
313 		return ret;
314 
315 	return size;
316 }
317 
318 static int tc_aux_read_data(struct tc_data *tc, void *data, size_t size)
319 {
320 	u32 auxrdata[DP_AUX_MAX_PAYLOAD_BYTES / sizeof(u32)];
321 	int ret, count = ALIGN(size, sizeof(u32));
322 
323 	ret = regmap_raw_read(tc->regmap, DP0_AUXRDATA(0), auxrdata, count);
324 	if (ret)
325 		return ret;
326 
327 	memcpy(data, auxrdata, size);
328 
329 	return size;
330 }
331 
332 static u32 tc_auxcfg0(struct drm_dp_aux_msg *msg, size_t size)
333 {
334 	u32 auxcfg0 = msg->request;
335 
336 	if (size)
337 		auxcfg0 |= FIELD_PREP(DP0_AUXCFG0_BSIZE, size - 1);
338 	else
339 		auxcfg0 |= DP0_AUXCFG0_ADDR_ONLY;
340 
341 	return auxcfg0;
342 }
343 
344 static ssize_t tc_aux_transfer(struct drm_dp_aux *aux,
345 			       struct drm_dp_aux_msg *msg)
346 {
347 	struct tc_data *tc = aux_to_tc(aux);
348 	size_t size = min_t(size_t, DP_AUX_MAX_PAYLOAD_BYTES - 1, msg->size);
349 	u8 request = msg->request & ~DP_AUX_I2C_MOT;
350 	u32 auxstatus;
351 	int ret;
352 
353 	ret = tc_aux_wait_busy(tc);
354 	if (ret)
355 		return ret;
356 
357 	switch (request) {
358 	case DP_AUX_NATIVE_READ:
359 	case DP_AUX_I2C_READ:
360 		break;
361 	case DP_AUX_NATIVE_WRITE:
362 	case DP_AUX_I2C_WRITE:
363 		if (size) {
364 			ret = tc_aux_write_data(tc, msg->buffer, size);
365 			if (ret < 0)
366 				return ret;
367 		}
368 		break;
369 	default:
370 		return -EINVAL;
371 	}
372 
373 	/* Store address */
374 	ret = regmap_write(tc->regmap, DP0_AUXADDR, msg->address);
375 	if (ret)
376 		return ret;
377 	/* Start transfer */
378 	ret = regmap_write(tc->regmap, DP0_AUXCFG0, tc_auxcfg0(msg, size));
379 	if (ret)
380 		return ret;
381 
382 	ret = tc_aux_wait_busy(tc);
383 	if (ret)
384 		return ret;
385 
386 	ret = regmap_read(tc->regmap, DP0_AUXSTATUS, &auxstatus);
387 	if (ret)
388 		return ret;
389 
390 	if (auxstatus & AUX_TIMEOUT)
391 		return -ETIMEDOUT;
392 	/*
393 	 * For some reason address-only DP_AUX_I2C_WRITE (MOT), still
394 	 * reports 1 byte transferred in its status. To deal we that
395 	 * we ignore aux_bytes field if we know that this was an
396 	 * address-only transfer
397 	 */
398 	if (size)
399 		size = FIELD_GET(AUX_BYTES, auxstatus);
400 	msg->reply = FIELD_GET(AUX_STATUS, auxstatus);
401 
402 	switch (request) {
403 	case DP_AUX_NATIVE_READ:
404 	case DP_AUX_I2C_READ:
405 		if (size)
406 			return tc_aux_read_data(tc, msg->buffer, size);
407 		break;
408 	}
409 
410 	return size;
411 }
412 
413 static const char * const training_pattern1_errors[] = {
414 	"No errors",
415 	"Aux write error",
416 	"Aux read error",
417 	"Max voltage reached error",
418 	"Loop counter expired error",
419 	"res", "res", "res"
420 };
421 
422 static const char * const training_pattern2_errors[] = {
423 	"No errors",
424 	"Aux write error",
425 	"Aux read error",
426 	"Clock recovery failed error",
427 	"Loop counter expired error",
428 	"res", "res", "res"
429 };
430 
431 static u32 tc_srcctrl(struct tc_data *tc)
432 {
433 	/*
434 	 * No training pattern, skew lane 1 data by two LSCLK cycles with
435 	 * respect to lane 0 data, AutoCorrect Mode = 0
436 	 */
437 	u32 reg = DP0_SRCCTRL_NOTP | DP0_SRCCTRL_LANESKEW | DP0_SRCCTRL_EN810B;
438 
439 	if (tc->link.scrambler_dis)
440 		reg |= DP0_SRCCTRL_SCRMBLDIS;	/* Scrambler Disabled */
441 	if (tc->link.spread)
442 		reg |= DP0_SRCCTRL_SSCG;	/* Spread Spectrum Enable */
443 	if (tc->link.num_lanes == 2)
444 		reg |= DP0_SRCCTRL_LANES_2;	/* Two Main Channel Lanes */
445 	if (tc->link.rate != 162000)
446 		reg |= DP0_SRCCTRL_BW27;	/* 2.7 Gbps link */
447 	return reg;
448 }
449 
450 static int tc_pllupdate(struct tc_data *tc, unsigned int pllctrl)
451 {
452 	int ret;
453 
454 	ret = regmap_write(tc->regmap, pllctrl, PLLUPDATE | PLLEN);
455 	if (ret)
456 		return ret;
457 
458 	/* Wait for PLL to lock: up to 2.09 ms, depending on refclk */
459 	usleep_range(3000, 6000);
460 
461 	return 0;
462 }
463 
464 static int tc_pxl_pll_en(struct tc_data *tc, u32 refclk, u32 pixelclock)
465 {
466 	int ret;
467 	int i_pre, best_pre = 1;
468 	int i_post, best_post = 1;
469 	int div, best_div = 1;
470 	int mul, best_mul = 1;
471 	int delta, best_delta;
472 	int ext_div[] = {1, 2, 3, 5, 7};
473 	int best_pixelclock = 0;
474 	int vco_hi = 0;
475 	u32 pxl_pllparam;
476 
477 	dev_dbg(tc->dev, "PLL: requested %d pixelclock, ref %d\n", pixelclock,
478 		refclk);
479 	best_delta = pixelclock;
480 	/* Loop over all possible ext_divs, skipping invalid configurations */
481 	for (i_pre = 0; i_pre < ARRAY_SIZE(ext_div); i_pre++) {
482 		/*
483 		 * refclk / ext_pre_div should be in the 1 to 200 MHz range.
484 		 * We don't allow any refclk > 200 MHz, only check lower bounds.
485 		 */
486 		if (refclk / ext_div[i_pre] < 1000000)
487 			continue;
488 		for (i_post = 0; i_post < ARRAY_SIZE(ext_div); i_post++) {
489 			for (div = 1; div <= 16; div++) {
490 				u32 clk;
491 				u64 tmp;
492 
493 				tmp = pixelclock * ext_div[i_pre] *
494 				      ext_div[i_post] * div;
495 				do_div(tmp, refclk);
496 				mul = tmp;
497 
498 				/* Check limits */
499 				if ((mul < 1) || (mul > 128))
500 					continue;
501 
502 				clk = (refclk / ext_div[i_pre] / div) * mul;
503 				/*
504 				 * refclk * mul / (ext_pre_div * pre_div)
505 				 * should be in the 150 to 650 MHz range
506 				 */
507 				if ((clk > 650000000) || (clk < 150000000))
508 					continue;
509 
510 				clk = clk / ext_div[i_post];
511 				delta = clk - pixelclock;
512 
513 				if (abs(delta) < abs(best_delta)) {
514 					best_pre = i_pre;
515 					best_post = i_post;
516 					best_div = div;
517 					best_mul = mul;
518 					best_delta = delta;
519 					best_pixelclock = clk;
520 				}
521 			}
522 		}
523 	}
524 	if (best_pixelclock == 0) {
525 		dev_err(tc->dev, "Failed to calc clock for %d pixelclock\n",
526 			pixelclock);
527 		return -EINVAL;
528 	}
529 
530 	dev_dbg(tc->dev, "PLL: got %d, delta %d\n", best_pixelclock,
531 		best_delta);
532 	dev_dbg(tc->dev, "PLL: %d / %d / %d * %d / %d\n", refclk,
533 		ext_div[best_pre], best_div, best_mul, ext_div[best_post]);
534 
535 	/* if VCO >= 300 MHz */
536 	if (refclk / ext_div[best_pre] / best_div * best_mul >= 300000000)
537 		vco_hi = 1;
538 	/* see DS */
539 	if (best_div == 16)
540 		best_div = 0;
541 	if (best_mul == 128)
542 		best_mul = 0;
543 
544 	/* Power up PLL and switch to bypass */
545 	ret = regmap_write(tc->regmap, PXL_PLLCTRL, PLLBYP | PLLEN);
546 	if (ret)
547 		return ret;
548 
549 	pxl_pllparam  = vco_hi << 24; /* For PLL VCO >= 300 MHz = 1 */
550 	pxl_pllparam |= ext_div[best_pre] << 20; /* External Pre-divider */
551 	pxl_pllparam |= ext_div[best_post] << 16; /* External Post-divider */
552 	pxl_pllparam |= IN_SEL_REFCLK; /* Use RefClk as PLL input */
553 	pxl_pllparam |= best_div << 8; /* Divider for PLL RefClk */
554 	pxl_pllparam |= best_mul; /* Multiplier for PLL */
555 
556 	ret = regmap_write(tc->regmap, PXL_PLLPARAM, pxl_pllparam);
557 	if (ret)
558 		return ret;
559 
560 	/* Force PLL parameter update and disable bypass */
561 	return tc_pllupdate(tc, PXL_PLLCTRL);
562 }
563 
564 static int tc_pxl_pll_dis(struct tc_data *tc)
565 {
566 	/* Enable PLL bypass, power down PLL */
567 	return regmap_write(tc->regmap, PXL_PLLCTRL, PLLBYP);
568 }
569 
570 static int tc_stream_clock_calc(struct tc_data *tc)
571 {
572 	/*
573 	 * If the Stream clock and Link Symbol clock are
574 	 * asynchronous with each other, the value of M changes over
575 	 * time. This way of generating link clock and stream
576 	 * clock is called Asynchronous Clock mode. The value M
577 	 * must change while the value N stays constant. The
578 	 * value of N in this Asynchronous Clock mode must be set
579 	 * to 2^15 or 32,768.
580 	 *
581 	 * LSCLK = 1/10 of high speed link clock
582 	 *
583 	 * f_STRMCLK = M/N * f_LSCLK
584 	 * M/N = f_STRMCLK / f_LSCLK
585 	 *
586 	 */
587 	return regmap_write(tc->regmap, DP0_VIDMNGEN1, 32768);
588 }
589 
590 static int tc_set_syspllparam(struct tc_data *tc)
591 {
592 	unsigned long rate;
593 	u32 pllparam = SYSCLK_SEL_LSCLK | LSCLK_DIV_2;
594 
595 	rate = clk_get_rate(tc->refclk);
596 	switch (rate) {
597 	case 38400000:
598 		pllparam |= REF_FREQ_38M4;
599 		break;
600 	case 26000000:
601 		pllparam |= REF_FREQ_26M;
602 		break;
603 	case 19200000:
604 		pllparam |= REF_FREQ_19M2;
605 		break;
606 	case 13000000:
607 		pllparam |= REF_FREQ_13M;
608 		break;
609 	default:
610 		dev_err(tc->dev, "Invalid refclk rate: %lu Hz\n", rate);
611 		return -EINVAL;
612 	}
613 
614 	return regmap_write(tc->regmap, SYS_PLLPARAM, pllparam);
615 }
616 
617 static int tc_aux_link_setup(struct tc_data *tc)
618 {
619 	int ret;
620 	u32 dp0_auxcfg1;
621 
622 	/* Setup DP-PHY / PLL */
623 	ret = tc_set_syspllparam(tc);
624 	if (ret)
625 		goto err;
626 
627 	ret = regmap_write(tc->regmap, DP_PHY_CTRL,
628 			   BGREN | PWR_SW_EN | PHY_A0_EN);
629 	if (ret)
630 		goto err;
631 	/*
632 	 * Initially PLLs are in bypass. Force PLL parameter update,
633 	 * disable PLL bypass, enable PLL
634 	 */
635 	ret = tc_pllupdate(tc, DP0_PLLCTRL);
636 	if (ret)
637 		goto err;
638 
639 	ret = tc_pllupdate(tc, DP1_PLLCTRL);
640 	if (ret)
641 		goto err;
642 
643 	ret = tc_poll_timeout(tc, DP_PHY_CTRL, PHY_RDY, PHY_RDY, 100, 100000);
644 	if (ret == -ETIMEDOUT) {
645 		dev_err(tc->dev, "Timeout waiting for PHY to become ready");
646 		return ret;
647 	} else if (ret) {
648 		goto err;
649 	}
650 
651 	/* Setup AUX link */
652 	dp0_auxcfg1  = AUX_RX_FILTER_EN;
653 	dp0_auxcfg1 |= 0x06 << 8; /* Aux Bit Period Calculator Threshold */
654 	dp0_auxcfg1 |= 0x3f << 0; /* Aux Response Timeout Timer */
655 
656 	ret = regmap_write(tc->regmap, DP0_AUXCFG1, dp0_auxcfg1);
657 	if (ret)
658 		goto err;
659 
660 	return 0;
661 err:
662 	dev_err(tc->dev, "tc_aux_link_setup failed: %d\n", ret);
663 	return ret;
664 }
665 
666 static int tc_get_display_props(struct tc_data *tc)
667 {
668 	u8 revision, num_lanes;
669 	unsigned int rate;
670 	int ret;
671 	u8 reg;
672 
673 	/* Read DP Rx Link Capability */
674 	ret = drm_dp_dpcd_read(&tc->aux, DP_DPCD_REV, tc->link.dpcd,
675 			       DP_RECEIVER_CAP_SIZE);
676 	if (ret < 0)
677 		goto err_dpcd_read;
678 
679 	revision = tc->link.dpcd[DP_DPCD_REV];
680 	rate = drm_dp_max_link_rate(tc->link.dpcd);
681 	num_lanes = drm_dp_max_lane_count(tc->link.dpcd);
682 
683 	if (rate != 162000 && rate != 270000) {
684 		dev_dbg(tc->dev, "Falling to 2.7 Gbps rate\n");
685 		rate = 270000;
686 	}
687 
688 	tc->link.rate = rate;
689 
690 	if (num_lanes > 2) {
691 		dev_dbg(tc->dev, "Falling to 2 lanes\n");
692 		num_lanes = 2;
693 	}
694 
695 	tc->link.num_lanes = num_lanes;
696 
697 	ret = drm_dp_dpcd_readb(&tc->aux, DP_MAX_DOWNSPREAD, &reg);
698 	if (ret < 0)
699 		goto err_dpcd_read;
700 	tc->link.spread = reg & DP_MAX_DOWNSPREAD_0_5;
701 
702 	ret = drm_dp_dpcd_readb(&tc->aux, DP_MAIN_LINK_CHANNEL_CODING, &reg);
703 	if (ret < 0)
704 		goto err_dpcd_read;
705 
706 	tc->link.scrambler_dis = false;
707 	/* read assr */
708 	ret = drm_dp_dpcd_readb(&tc->aux, DP_EDP_CONFIGURATION_SET, &reg);
709 	if (ret < 0)
710 		goto err_dpcd_read;
711 	tc->link.assr = reg & DP_ALTERNATE_SCRAMBLER_RESET_ENABLE;
712 
713 	dev_dbg(tc->dev, "DPCD rev: %d.%d, rate: %s, lanes: %d, framing: %s\n",
714 		revision >> 4, revision & 0x0f,
715 		(tc->link.rate == 162000) ? "1.62Gbps" : "2.7Gbps",
716 		tc->link.num_lanes,
717 		drm_dp_enhanced_frame_cap(tc->link.dpcd) ?
718 		"enhanced" : "default");
719 	dev_dbg(tc->dev, "Downspread: %s, scrambler: %s\n",
720 		tc->link.spread ? "0.5%" : "0.0%",
721 		tc->link.scrambler_dis ? "disabled" : "enabled");
722 	dev_dbg(tc->dev, "Display ASSR: %d, TC358767 ASSR: %d\n",
723 		tc->link.assr, tc->assr);
724 
725 	return 0;
726 
727 err_dpcd_read:
728 	dev_err(tc->dev, "failed to read DPCD: %d\n", ret);
729 	return ret;
730 }
731 
732 static int tc_set_video_mode(struct tc_data *tc,
733 			     const struct drm_display_mode *mode)
734 {
735 	int ret;
736 	int vid_sync_dly;
737 	int max_tu_symbol;
738 
739 	int left_margin = mode->htotal - mode->hsync_end;
740 	int right_margin = mode->hsync_start - mode->hdisplay;
741 	int hsync_len = mode->hsync_end - mode->hsync_start;
742 	int upper_margin = mode->vtotal - mode->vsync_end;
743 	int lower_margin = mode->vsync_start - mode->vdisplay;
744 	int vsync_len = mode->vsync_end - mode->vsync_start;
745 	u32 dp0_syncval;
746 	u32 bits_per_pixel = 24;
747 	u32 in_bw, out_bw;
748 
749 	/*
750 	 * Recommended maximum number of symbols transferred in a transfer unit:
751 	 * DIV_ROUND_UP((input active video bandwidth in bytes) * tu_size,
752 	 *              (output active video bandwidth in bytes))
753 	 * Must be less than tu_size.
754 	 */
755 
756 	in_bw = mode->clock * bits_per_pixel / 8;
757 	out_bw = tc->link.num_lanes * tc->link.rate;
758 	max_tu_symbol = DIV_ROUND_UP(in_bw * TU_SIZE_RECOMMENDED, out_bw);
759 
760 	dev_dbg(tc->dev, "set mode %dx%d\n",
761 		mode->hdisplay, mode->vdisplay);
762 	dev_dbg(tc->dev, "H margin %d,%d sync %d\n",
763 		left_margin, right_margin, hsync_len);
764 	dev_dbg(tc->dev, "V margin %d,%d sync %d\n",
765 		upper_margin, lower_margin, vsync_len);
766 	dev_dbg(tc->dev, "total: %dx%d\n", mode->htotal, mode->vtotal);
767 
768 
769 	/*
770 	 * LCD Ctl Frame Size
771 	 * datasheet is not clear of vsdelay in case of DPI
772 	 * assume we do not need any delay when DPI is a source of
773 	 * sync signals
774 	 */
775 	ret = regmap_write(tc->regmap, VPCTRL0,
776 			   FIELD_PREP(VSDELAY, 0) |
777 			   OPXLFMT_RGB888 | FRMSYNC_DISABLED | MSF_DISABLED);
778 	if (ret)
779 		return ret;
780 
781 	ret = regmap_write(tc->regmap, HTIM01,
782 			   FIELD_PREP(HBPR, ALIGN(left_margin, 2)) |
783 			   FIELD_PREP(HPW, ALIGN(hsync_len, 2)));
784 	if (ret)
785 		return ret;
786 
787 	ret = regmap_write(tc->regmap, HTIM02,
788 			   FIELD_PREP(HDISPR, ALIGN(mode->hdisplay, 2)) |
789 			   FIELD_PREP(HFPR, ALIGN(right_margin, 2)));
790 	if (ret)
791 		return ret;
792 
793 	ret = regmap_write(tc->regmap, VTIM01,
794 			   FIELD_PREP(VBPR, upper_margin) |
795 			   FIELD_PREP(VSPR, vsync_len));
796 	if (ret)
797 		return ret;
798 
799 	ret = regmap_write(tc->regmap, VTIM02,
800 			   FIELD_PREP(VFPR, lower_margin) |
801 			   FIELD_PREP(VDISPR, mode->vdisplay));
802 	if (ret)
803 		return ret;
804 
805 	ret = regmap_write(tc->regmap, VFUEN0, VFUEN); /* update settings */
806 	if (ret)
807 		return ret;
808 
809 	/* Test pattern settings */
810 	ret = regmap_write(tc->regmap, TSTCTL,
811 			   FIELD_PREP(COLOR_R, 120) |
812 			   FIELD_PREP(COLOR_G, 20) |
813 			   FIELD_PREP(COLOR_B, 99) |
814 			   ENI2CFILTER |
815 			   FIELD_PREP(COLOR_BAR_MODE, COLOR_BAR_MODE_BARS));
816 	if (ret)
817 		return ret;
818 
819 	/* DP Main Stream Attributes */
820 	vid_sync_dly = hsync_len + left_margin + mode->hdisplay;
821 	ret = regmap_write(tc->regmap, DP0_VIDSYNCDELAY,
822 		 FIELD_PREP(THRESH_DLY, max_tu_symbol) |
823 		 FIELD_PREP(VID_SYNC_DLY, vid_sync_dly));
824 
825 	ret = regmap_write(tc->regmap, DP0_TOTALVAL,
826 			   FIELD_PREP(H_TOTAL, mode->htotal) |
827 			   FIELD_PREP(V_TOTAL, mode->vtotal));
828 	if (ret)
829 		return ret;
830 
831 	ret = regmap_write(tc->regmap, DP0_STARTVAL,
832 			   FIELD_PREP(H_START, left_margin + hsync_len) |
833 			   FIELD_PREP(V_START, upper_margin + vsync_len));
834 	if (ret)
835 		return ret;
836 
837 	ret = regmap_write(tc->regmap, DP0_ACTIVEVAL,
838 			   FIELD_PREP(V_ACT, mode->vdisplay) |
839 			   FIELD_PREP(H_ACT, mode->hdisplay));
840 	if (ret)
841 		return ret;
842 
843 	dp0_syncval = FIELD_PREP(VS_WIDTH, vsync_len) |
844 		      FIELD_PREP(HS_WIDTH, hsync_len);
845 
846 	if (mode->flags & DRM_MODE_FLAG_NVSYNC)
847 		dp0_syncval |= SYNCVAL_VS_POL_ACTIVE_LOW;
848 
849 	if (mode->flags & DRM_MODE_FLAG_NHSYNC)
850 		dp0_syncval |= SYNCVAL_HS_POL_ACTIVE_LOW;
851 
852 	ret = regmap_write(tc->regmap, DP0_SYNCVAL, dp0_syncval);
853 	if (ret)
854 		return ret;
855 
856 	ret = regmap_write(tc->regmap, DPIPXLFMT,
857 			   VS_POL_ACTIVE_LOW | HS_POL_ACTIVE_LOW |
858 			   DE_POL_ACTIVE_HIGH | SUB_CFG_TYPE_CONFIG1 |
859 			   DPI_BPP_RGB888);
860 	if (ret)
861 		return ret;
862 
863 	ret = regmap_write(tc->regmap, DP0_MISC,
864 			   FIELD_PREP(MAX_TU_SYMBOL, max_tu_symbol) |
865 			   FIELD_PREP(TU_SIZE, TU_SIZE_RECOMMENDED) |
866 			   BPC_8);
867 	if (ret)
868 		return ret;
869 
870 	return 0;
871 }
872 
873 static int tc_wait_link_training(struct tc_data *tc)
874 {
875 	u32 value;
876 	int ret;
877 
878 	ret = tc_poll_timeout(tc, DP0_LTSTAT, LT_LOOPDONE,
879 			      LT_LOOPDONE, 500, 100000);
880 	if (ret) {
881 		dev_err(tc->dev, "Link training timeout waiting for LT_LOOPDONE!\n");
882 		return ret;
883 	}
884 
885 	ret = regmap_read(tc->regmap, DP0_LTSTAT, &value);
886 	if (ret)
887 		return ret;
888 
889 	return (value >> 8) & 0x7;
890 }
891 
892 static int tc_main_link_enable(struct tc_data *tc)
893 {
894 	struct drm_dp_aux *aux = &tc->aux;
895 	struct device *dev = tc->dev;
896 	u32 dp_phy_ctrl;
897 	u32 value;
898 	int ret;
899 	u8 tmp[DP_LINK_STATUS_SIZE];
900 
901 	dev_dbg(tc->dev, "link enable\n");
902 
903 	ret = regmap_read(tc->regmap, DP0CTL, &value);
904 	if (ret)
905 		return ret;
906 
907 	if (WARN_ON(value & DP_EN)) {
908 		ret = regmap_write(tc->regmap, DP0CTL, 0);
909 		if (ret)
910 			return ret;
911 	}
912 
913 	ret = regmap_write(tc->regmap, DP0_SRCCTRL, tc_srcctrl(tc));
914 	if (ret)
915 		return ret;
916 	/* SSCG and BW27 on DP1 must be set to the same as on DP0 */
917 	ret = regmap_write(tc->regmap, DP1_SRCCTRL,
918 		 (tc->link.spread ? DP0_SRCCTRL_SSCG : 0) |
919 		 ((tc->link.rate != 162000) ? DP0_SRCCTRL_BW27 : 0));
920 	if (ret)
921 		return ret;
922 
923 	ret = tc_set_syspllparam(tc);
924 	if (ret)
925 		return ret;
926 
927 	/* Setup Main Link */
928 	dp_phy_ctrl = BGREN | PWR_SW_EN | PHY_A0_EN | PHY_M0_EN;
929 	if (tc->link.num_lanes == 2)
930 		dp_phy_ctrl |= PHY_2LANE;
931 
932 	ret = regmap_write(tc->regmap, DP_PHY_CTRL, dp_phy_ctrl);
933 	if (ret)
934 		return ret;
935 
936 	/* PLL setup */
937 	ret = tc_pllupdate(tc, DP0_PLLCTRL);
938 	if (ret)
939 		return ret;
940 
941 	ret = tc_pllupdate(tc, DP1_PLLCTRL);
942 	if (ret)
943 		return ret;
944 
945 	/* Reset/Enable Main Links */
946 	dp_phy_ctrl |= DP_PHY_RST | PHY_M1_RST | PHY_M0_RST;
947 	ret = regmap_write(tc->regmap, DP_PHY_CTRL, dp_phy_ctrl);
948 	usleep_range(100, 200);
949 	dp_phy_ctrl &= ~(DP_PHY_RST | PHY_M1_RST | PHY_M0_RST);
950 	ret = regmap_write(tc->regmap, DP_PHY_CTRL, dp_phy_ctrl);
951 
952 	ret = tc_poll_timeout(tc, DP_PHY_CTRL, PHY_RDY, PHY_RDY, 500, 100000);
953 	if (ret) {
954 		dev_err(dev, "timeout waiting for phy become ready");
955 		return ret;
956 	}
957 
958 	/* Set misc: 8 bits per color */
959 	ret = regmap_update_bits(tc->regmap, DP0_MISC, BPC_8, BPC_8);
960 	if (ret)
961 		return ret;
962 
963 	/*
964 	 * ASSR mode
965 	 * on TC358767 side ASSR configured through strap pin
966 	 * seems there is no way to change this setting from SW
967 	 *
968 	 * check is tc configured for same mode
969 	 */
970 	if (tc->assr != tc->link.assr) {
971 		dev_dbg(dev, "Trying to set display to ASSR: %d\n",
972 			tc->assr);
973 		/* try to set ASSR on display side */
974 		tmp[0] = tc->assr;
975 		ret = drm_dp_dpcd_writeb(aux, DP_EDP_CONFIGURATION_SET, tmp[0]);
976 		if (ret < 0)
977 			goto err_dpcd_read;
978 		/* read back */
979 		ret = drm_dp_dpcd_readb(aux, DP_EDP_CONFIGURATION_SET, tmp);
980 		if (ret < 0)
981 			goto err_dpcd_read;
982 
983 		if (tmp[0] != tc->assr) {
984 			dev_dbg(dev, "Failed to switch display ASSR to %d, falling back to unscrambled mode\n",
985 				tc->assr);
986 			/* trying with disabled scrambler */
987 			tc->link.scrambler_dis = true;
988 		}
989 	}
990 
991 	/* Setup Link & DPRx Config for Training */
992 	tmp[0] = drm_dp_link_rate_to_bw_code(tc->link.rate);
993 	tmp[1] = tc->link.num_lanes;
994 
995 	if (drm_dp_enhanced_frame_cap(tc->link.dpcd))
996 		tmp[1] |= DP_LANE_COUNT_ENHANCED_FRAME_EN;
997 
998 	ret = drm_dp_dpcd_write(aux, DP_LINK_BW_SET, tmp, 2);
999 	if (ret < 0)
1000 		goto err_dpcd_write;
1001 
1002 	/* DOWNSPREAD_CTRL */
1003 	tmp[0] = tc->link.spread ? DP_SPREAD_AMP_0_5 : 0x00;
1004 	/* MAIN_LINK_CHANNEL_CODING_SET */
1005 	tmp[1] =  DP_SET_ANSI_8B10B;
1006 	ret = drm_dp_dpcd_write(aux, DP_DOWNSPREAD_CTRL, tmp, 2);
1007 	if (ret < 0)
1008 		goto err_dpcd_write;
1009 
1010 	/* Reset voltage-swing & pre-emphasis */
1011 	tmp[0] = tmp[1] = DP_TRAIN_VOLTAGE_SWING_LEVEL_0 |
1012 			  DP_TRAIN_PRE_EMPH_LEVEL_0;
1013 	ret = drm_dp_dpcd_write(aux, DP_TRAINING_LANE0_SET, tmp, 2);
1014 	if (ret < 0)
1015 		goto err_dpcd_write;
1016 
1017 	/* Clock-Recovery */
1018 
1019 	/* Set DPCD 0x102 for Training Pattern 1 */
1020 	ret = regmap_write(tc->regmap, DP0_SNKLTCTRL,
1021 			   DP_LINK_SCRAMBLING_DISABLE |
1022 			   DP_TRAINING_PATTERN_1);
1023 	if (ret)
1024 		return ret;
1025 
1026 	ret = regmap_write(tc->regmap, DP0_LTLOOPCTRL,
1027 			   (15 << 28) |	/* Defer Iteration Count */
1028 			   (15 << 24) |	/* Loop Iteration Count */
1029 			   (0xd << 0));	/* Loop Timer Delay */
1030 	if (ret)
1031 		return ret;
1032 
1033 	ret = regmap_write(tc->regmap, DP0_SRCCTRL,
1034 			   tc_srcctrl(tc) | DP0_SRCCTRL_SCRMBLDIS |
1035 			   DP0_SRCCTRL_AUTOCORRECT |
1036 			   DP0_SRCCTRL_TP1);
1037 	if (ret)
1038 		return ret;
1039 
1040 	/* Enable DP0 to start Link Training */
1041 	ret = regmap_write(tc->regmap, DP0CTL,
1042 			   (drm_dp_enhanced_frame_cap(tc->link.dpcd) ?
1043 				EF_EN : 0) | DP_EN);
1044 	if (ret)
1045 		return ret;
1046 
1047 	/* wait */
1048 
1049 	ret = tc_wait_link_training(tc);
1050 	if (ret < 0)
1051 		return ret;
1052 
1053 	if (ret) {
1054 		dev_err(tc->dev, "Link training phase 1 failed: %s\n",
1055 			training_pattern1_errors[ret]);
1056 		return -ENODEV;
1057 	}
1058 
1059 	/* Channel Equalization */
1060 
1061 	/* Set DPCD 0x102 for Training Pattern 2 */
1062 	ret = regmap_write(tc->regmap, DP0_SNKLTCTRL,
1063 			   DP_LINK_SCRAMBLING_DISABLE |
1064 			   DP_TRAINING_PATTERN_2);
1065 	if (ret)
1066 		return ret;
1067 
1068 	ret = regmap_write(tc->regmap, DP0_SRCCTRL,
1069 			   tc_srcctrl(tc) | DP0_SRCCTRL_SCRMBLDIS |
1070 			   DP0_SRCCTRL_AUTOCORRECT |
1071 			   DP0_SRCCTRL_TP2);
1072 	if (ret)
1073 		return ret;
1074 
1075 	/* wait */
1076 	ret = tc_wait_link_training(tc);
1077 	if (ret < 0)
1078 		return ret;
1079 
1080 	if (ret) {
1081 		dev_err(tc->dev, "Link training phase 2 failed: %s\n",
1082 			training_pattern2_errors[ret]);
1083 		return -ENODEV;
1084 	}
1085 
1086 	/*
1087 	 * Toshiba's documentation suggests to first clear DPCD 0x102, then
1088 	 * clear the training pattern bit in DP0_SRCCTRL. Testing shows
1089 	 * that the link sometimes drops if those steps are done in that order,
1090 	 * but if the steps are done in reverse order, the link stays up.
1091 	 *
1092 	 * So we do the steps differently than documented here.
1093 	 */
1094 
1095 	/* Clear Training Pattern, set AutoCorrect Mode = 1 */
1096 	ret = regmap_write(tc->regmap, DP0_SRCCTRL, tc_srcctrl(tc) |
1097 			   DP0_SRCCTRL_AUTOCORRECT);
1098 	if (ret)
1099 		return ret;
1100 
1101 	/* Clear DPCD 0x102 */
1102 	/* Note: Can Not use DP0_SNKLTCTRL (0x06E4) short cut */
1103 	tmp[0] = tc->link.scrambler_dis ? DP_LINK_SCRAMBLING_DISABLE : 0x00;
1104 	ret = drm_dp_dpcd_writeb(aux, DP_TRAINING_PATTERN_SET, tmp[0]);
1105 	if (ret < 0)
1106 		goto err_dpcd_write;
1107 
1108 	/* Check link status */
1109 	ret = drm_dp_dpcd_read_link_status(aux, tmp);
1110 	if (ret < 0)
1111 		goto err_dpcd_read;
1112 
1113 	ret = 0;
1114 
1115 	value = tmp[0] & DP_CHANNEL_EQ_BITS;
1116 
1117 	if (value != DP_CHANNEL_EQ_BITS) {
1118 		dev_err(tc->dev, "Lane 0 failed: %x\n", value);
1119 		ret = -ENODEV;
1120 	}
1121 
1122 	if (tc->link.num_lanes == 2) {
1123 		value = (tmp[0] >> 4) & DP_CHANNEL_EQ_BITS;
1124 
1125 		if (value != DP_CHANNEL_EQ_BITS) {
1126 			dev_err(tc->dev, "Lane 1 failed: %x\n", value);
1127 			ret = -ENODEV;
1128 		}
1129 
1130 		if (!(tmp[2] & DP_INTERLANE_ALIGN_DONE)) {
1131 			dev_err(tc->dev, "Interlane align failed\n");
1132 			ret = -ENODEV;
1133 		}
1134 	}
1135 
1136 	if (ret) {
1137 		dev_err(dev, "0x0202 LANE0_1_STATUS:            0x%02x\n", tmp[0]);
1138 		dev_err(dev, "0x0203 LANE2_3_STATUS             0x%02x\n", tmp[1]);
1139 		dev_err(dev, "0x0204 LANE_ALIGN_STATUS_UPDATED: 0x%02x\n", tmp[2]);
1140 		dev_err(dev, "0x0205 SINK_STATUS:               0x%02x\n", tmp[3]);
1141 		dev_err(dev, "0x0206 ADJUST_REQUEST_LANE0_1:    0x%02x\n", tmp[4]);
1142 		dev_err(dev, "0x0207 ADJUST_REQUEST_LANE2_3:    0x%02x\n", tmp[5]);
1143 		return ret;
1144 	}
1145 
1146 	return 0;
1147 err_dpcd_read:
1148 	dev_err(tc->dev, "Failed to read DPCD: %d\n", ret);
1149 	return ret;
1150 err_dpcd_write:
1151 	dev_err(tc->dev, "Failed to write DPCD: %d\n", ret);
1152 	return ret;
1153 }
1154 
1155 static int tc_main_link_disable(struct tc_data *tc)
1156 {
1157 	int ret;
1158 
1159 	dev_dbg(tc->dev, "link disable\n");
1160 
1161 	ret = regmap_write(tc->regmap, DP0_SRCCTRL, 0);
1162 	if (ret)
1163 		return ret;
1164 
1165 	return regmap_write(tc->regmap, DP0CTL, 0);
1166 }
1167 
1168 static int tc_stream_enable(struct tc_data *tc)
1169 {
1170 	int ret;
1171 	u32 value;
1172 
1173 	dev_dbg(tc->dev, "enable video stream\n");
1174 
1175 	/* PXL PLL setup */
1176 	if (tc_test_pattern) {
1177 		ret = tc_pxl_pll_en(tc, clk_get_rate(tc->refclk),
1178 				    1000 * tc->mode.clock);
1179 		if (ret)
1180 			return ret;
1181 	}
1182 
1183 	ret = tc_set_video_mode(tc, &tc->mode);
1184 	if (ret)
1185 		return ret;
1186 
1187 	/* Set M/N */
1188 	ret = tc_stream_clock_calc(tc);
1189 	if (ret)
1190 		return ret;
1191 
1192 	value = VID_MN_GEN | DP_EN;
1193 	if (drm_dp_enhanced_frame_cap(tc->link.dpcd))
1194 		value |= EF_EN;
1195 	ret = regmap_write(tc->regmap, DP0CTL, value);
1196 	if (ret)
1197 		return ret;
1198 	/*
1199 	 * VID_EN assertion should be delayed by at least N * LSCLK
1200 	 * cycles from the time VID_MN_GEN is enabled in order to
1201 	 * generate stable values for VID_M. LSCLK is 270 MHz or
1202 	 * 162 MHz, VID_N is set to 32768 in  tc_stream_clock_calc(),
1203 	 * so a delay of at least 203 us should suffice.
1204 	 */
1205 	usleep_range(500, 1000);
1206 	value |= VID_EN;
1207 	ret = regmap_write(tc->regmap, DP0CTL, value);
1208 	if (ret)
1209 		return ret;
1210 	/* Set input interface */
1211 	value = DP0_AUDSRC_NO_INPUT;
1212 	if (tc_test_pattern)
1213 		value |= DP0_VIDSRC_COLOR_BAR;
1214 	else
1215 		value |= DP0_VIDSRC_DPI_RX;
1216 	ret = regmap_write(tc->regmap, SYSCTRL, value);
1217 	if (ret)
1218 		return ret;
1219 
1220 	return 0;
1221 }
1222 
1223 static int tc_stream_disable(struct tc_data *tc)
1224 {
1225 	int ret;
1226 
1227 	dev_dbg(tc->dev, "disable video stream\n");
1228 
1229 	ret = regmap_update_bits(tc->regmap, DP0CTL, VID_EN, 0);
1230 	if (ret)
1231 		return ret;
1232 
1233 	tc_pxl_pll_dis(tc);
1234 
1235 	return 0;
1236 }
1237 
1238 static void tc_bridge_pre_enable(struct drm_bridge *bridge)
1239 {
1240 	struct tc_data *tc = bridge_to_tc(bridge);
1241 
1242 	drm_panel_prepare(tc->panel);
1243 }
1244 
1245 static void tc_bridge_enable(struct drm_bridge *bridge)
1246 {
1247 	struct tc_data *tc = bridge_to_tc(bridge);
1248 	int ret;
1249 
1250 	ret = tc_get_display_props(tc);
1251 	if (ret < 0) {
1252 		dev_err(tc->dev, "failed to read display props: %d\n", ret);
1253 		return;
1254 	}
1255 
1256 	ret = tc_main_link_enable(tc);
1257 	if (ret < 0) {
1258 		dev_err(tc->dev, "main link enable error: %d\n", ret);
1259 		return;
1260 	}
1261 
1262 	ret = tc_stream_enable(tc);
1263 	if (ret < 0) {
1264 		dev_err(tc->dev, "main link stream start error: %d\n", ret);
1265 		tc_main_link_disable(tc);
1266 		return;
1267 	}
1268 
1269 	drm_panel_enable(tc->panel);
1270 }
1271 
1272 static void tc_bridge_disable(struct drm_bridge *bridge)
1273 {
1274 	struct tc_data *tc = bridge_to_tc(bridge);
1275 	int ret;
1276 
1277 	drm_panel_disable(tc->panel);
1278 
1279 	ret = tc_stream_disable(tc);
1280 	if (ret < 0)
1281 		dev_err(tc->dev, "main link stream stop error: %d\n", ret);
1282 
1283 	ret = tc_main_link_disable(tc);
1284 	if (ret < 0)
1285 		dev_err(tc->dev, "main link disable error: %d\n", ret);
1286 }
1287 
1288 static void tc_bridge_post_disable(struct drm_bridge *bridge)
1289 {
1290 	struct tc_data *tc = bridge_to_tc(bridge);
1291 
1292 	drm_panel_unprepare(tc->panel);
1293 }
1294 
1295 static bool tc_bridge_mode_fixup(struct drm_bridge *bridge,
1296 				 const struct drm_display_mode *mode,
1297 				 struct drm_display_mode *adj)
1298 {
1299 	/* Fixup sync polarities, both hsync and vsync are active low */
1300 	adj->flags = mode->flags;
1301 	adj->flags |= (DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC);
1302 	adj->flags &= ~(DRM_MODE_FLAG_PHSYNC | DRM_MODE_FLAG_PVSYNC);
1303 
1304 	return true;
1305 }
1306 
1307 static enum drm_mode_status tc_mode_valid(struct drm_bridge *bridge,
1308 					  const struct drm_display_mode *mode)
1309 {
1310 	struct tc_data *tc = bridge_to_tc(bridge);
1311 	u32 req, avail;
1312 	u32 bits_per_pixel = 24;
1313 
1314 	/* DPI interface clock limitation: upto 154 MHz */
1315 	if (mode->clock > 154000)
1316 		return MODE_CLOCK_HIGH;
1317 
1318 	req = mode->clock * bits_per_pixel / 8;
1319 	avail = tc->link.num_lanes * tc->link.rate;
1320 
1321 	if (req > avail)
1322 		return MODE_BAD;
1323 
1324 	return MODE_OK;
1325 }
1326 
1327 static void tc_bridge_mode_set(struct drm_bridge *bridge,
1328 			       const struct drm_display_mode *mode,
1329 			       const struct drm_display_mode *adj)
1330 {
1331 	struct tc_data *tc = bridge_to_tc(bridge);
1332 
1333 	tc->mode = *mode;
1334 }
1335 
1336 static int tc_connector_get_modes(struct drm_connector *connector)
1337 {
1338 	struct tc_data *tc = connector_to_tc(connector);
1339 	struct edid *edid;
1340 	int count;
1341 	int ret;
1342 
1343 	ret = tc_get_display_props(tc);
1344 	if (ret < 0) {
1345 		dev_err(tc->dev, "failed to read display props: %d\n", ret);
1346 		return 0;
1347 	}
1348 
1349 	count = drm_panel_get_modes(tc->panel, connector);
1350 	if (count > 0)
1351 		return count;
1352 
1353 	edid = drm_get_edid(connector, &tc->aux.ddc);
1354 
1355 	kfree(tc->edid);
1356 	tc->edid = edid;
1357 	if (!edid)
1358 		return 0;
1359 
1360 	drm_connector_update_edid_property(connector, edid);
1361 	count = drm_add_edid_modes(connector, edid);
1362 
1363 	return count;
1364 }
1365 
1366 static const struct drm_connector_helper_funcs tc_connector_helper_funcs = {
1367 	.get_modes = tc_connector_get_modes,
1368 };
1369 
1370 static enum drm_connector_status tc_connector_detect(struct drm_connector *connector,
1371 						     bool force)
1372 {
1373 	struct tc_data *tc = connector_to_tc(connector);
1374 	bool conn;
1375 	u32 val;
1376 	int ret;
1377 
1378 	if (tc->hpd_pin < 0) {
1379 		if (tc->panel)
1380 			return connector_status_connected;
1381 		else
1382 			return connector_status_unknown;
1383 	}
1384 
1385 	ret = regmap_read(tc->regmap, GPIOI, &val);
1386 	if (ret)
1387 		return connector_status_unknown;
1388 
1389 	conn = val & BIT(tc->hpd_pin);
1390 
1391 	if (conn)
1392 		return connector_status_connected;
1393 	else
1394 		return connector_status_disconnected;
1395 }
1396 
1397 static const struct drm_connector_funcs tc_connector_funcs = {
1398 	.detect = tc_connector_detect,
1399 	.fill_modes = drm_helper_probe_single_connector_modes,
1400 	.destroy = drm_connector_cleanup,
1401 	.reset = drm_atomic_helper_connector_reset,
1402 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
1403 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
1404 };
1405 
1406 static int tc_bridge_attach(struct drm_bridge *bridge)
1407 {
1408 	u32 bus_format = MEDIA_BUS_FMT_RGB888_1X24;
1409 	struct tc_data *tc = bridge_to_tc(bridge);
1410 	struct drm_device *drm = bridge->dev;
1411 	int ret;
1412 
1413 	/* Create DP/eDP connector */
1414 	drm_connector_helper_add(&tc->connector, &tc_connector_helper_funcs);
1415 	ret = drm_connector_init(drm, &tc->connector, &tc_connector_funcs,
1416 				 tc->panel ? DRM_MODE_CONNECTOR_eDP :
1417 				 DRM_MODE_CONNECTOR_DisplayPort);
1418 	if (ret)
1419 		return ret;
1420 
1421 	/* Don't poll if don't have HPD connected */
1422 	if (tc->hpd_pin >= 0) {
1423 		if (tc->have_irq)
1424 			tc->connector.polled = DRM_CONNECTOR_POLL_HPD;
1425 		else
1426 			tc->connector.polled = DRM_CONNECTOR_POLL_CONNECT |
1427 					       DRM_CONNECTOR_POLL_DISCONNECT;
1428 	}
1429 
1430 	if (tc->panel)
1431 		drm_panel_attach(tc->panel, &tc->connector);
1432 
1433 	drm_display_info_set_bus_formats(&tc->connector.display_info,
1434 					 &bus_format, 1);
1435 	tc->connector.display_info.bus_flags =
1436 		DRM_BUS_FLAG_DE_HIGH |
1437 		DRM_BUS_FLAG_PIXDATA_DRIVE_NEGEDGE |
1438 		DRM_BUS_FLAG_SYNC_DRIVE_NEGEDGE;
1439 	drm_connector_attach_encoder(&tc->connector, tc->bridge.encoder);
1440 
1441 	return 0;
1442 }
1443 
1444 static const struct drm_bridge_funcs tc_bridge_funcs = {
1445 	.attach = tc_bridge_attach,
1446 	.mode_valid = tc_mode_valid,
1447 	.mode_set = tc_bridge_mode_set,
1448 	.pre_enable = tc_bridge_pre_enable,
1449 	.enable = tc_bridge_enable,
1450 	.disable = tc_bridge_disable,
1451 	.post_disable = tc_bridge_post_disable,
1452 	.mode_fixup = tc_bridge_mode_fixup,
1453 };
1454 
1455 static bool tc_readable_reg(struct device *dev, unsigned int reg)
1456 {
1457 	return reg != SYSCTRL;
1458 }
1459 
1460 static const struct regmap_range tc_volatile_ranges[] = {
1461 	regmap_reg_range(DP0_AUXWDATA(0), DP0_AUXSTATUS),
1462 	regmap_reg_range(DP0_LTSTAT, DP0_SNKLTCHGREQ),
1463 	regmap_reg_range(DP_PHY_CTRL, DP_PHY_CTRL),
1464 	regmap_reg_range(DP0_PLLCTRL, PXL_PLLCTRL),
1465 	regmap_reg_range(VFUEN0, VFUEN0),
1466 	regmap_reg_range(INTSTS_G, INTSTS_G),
1467 	regmap_reg_range(GPIOI, GPIOI),
1468 };
1469 
1470 static const struct regmap_access_table tc_volatile_table = {
1471 	.yes_ranges = tc_volatile_ranges,
1472 	.n_yes_ranges = ARRAY_SIZE(tc_volatile_ranges),
1473 };
1474 
1475 static bool tc_writeable_reg(struct device *dev, unsigned int reg)
1476 {
1477 	return (reg != TC_IDREG) &&
1478 	       (reg != DP0_LTSTAT) &&
1479 	       (reg != DP0_SNKLTCHGREQ);
1480 }
1481 
1482 static const struct regmap_config tc_regmap_config = {
1483 	.name = "tc358767",
1484 	.reg_bits = 16,
1485 	.val_bits = 32,
1486 	.reg_stride = 4,
1487 	.max_register = PLL_DBG,
1488 	.cache_type = REGCACHE_RBTREE,
1489 	.readable_reg = tc_readable_reg,
1490 	.volatile_table = &tc_volatile_table,
1491 	.writeable_reg = tc_writeable_reg,
1492 	.reg_format_endian = REGMAP_ENDIAN_BIG,
1493 	.val_format_endian = REGMAP_ENDIAN_LITTLE,
1494 };
1495 
1496 static irqreturn_t tc_irq_handler(int irq, void *arg)
1497 {
1498 	struct tc_data *tc = arg;
1499 	u32 val;
1500 	int r;
1501 
1502 	r = regmap_read(tc->regmap, INTSTS_G, &val);
1503 	if (r)
1504 		return IRQ_NONE;
1505 
1506 	if (!val)
1507 		return IRQ_NONE;
1508 
1509 	if (val & INT_SYSERR) {
1510 		u32 stat = 0;
1511 
1512 		regmap_read(tc->regmap, SYSSTAT, &stat);
1513 
1514 		dev_err(tc->dev, "syserr %x\n", stat);
1515 	}
1516 
1517 	if (tc->hpd_pin >= 0 && tc->bridge.dev) {
1518 		/*
1519 		 * H is triggered when the GPIO goes high.
1520 		 *
1521 		 * LC is triggered when the GPIO goes low and stays low for
1522 		 * the duration of LCNT
1523 		 */
1524 		bool h = val & INT_GPIO_H(tc->hpd_pin);
1525 		bool lc = val & INT_GPIO_LC(tc->hpd_pin);
1526 
1527 		dev_dbg(tc->dev, "GPIO%d: %s %s\n", tc->hpd_pin,
1528 			h ? "H" : "", lc ? "LC" : "");
1529 
1530 		if (h || lc)
1531 			drm_kms_helper_hotplug_event(tc->bridge.dev);
1532 	}
1533 
1534 	regmap_write(tc->regmap, INTSTS_G, val);
1535 
1536 	return IRQ_HANDLED;
1537 }
1538 
1539 static int tc_probe(struct i2c_client *client, const struct i2c_device_id *id)
1540 {
1541 	struct device *dev = &client->dev;
1542 	struct tc_data *tc;
1543 	int ret;
1544 
1545 	tc = devm_kzalloc(dev, sizeof(*tc), GFP_KERNEL);
1546 	if (!tc)
1547 		return -ENOMEM;
1548 
1549 	tc->dev = dev;
1550 
1551 	/* port@2 is the output port */
1552 	ret = drm_of_find_panel_or_bridge(dev->of_node, 2, 0, &tc->panel, NULL);
1553 	if (ret && ret != -ENODEV)
1554 		return ret;
1555 
1556 	/* Shut down GPIO is optional */
1557 	tc->sd_gpio = devm_gpiod_get_optional(dev, "shutdown", GPIOD_OUT_HIGH);
1558 	if (IS_ERR(tc->sd_gpio))
1559 		return PTR_ERR(tc->sd_gpio);
1560 
1561 	if (tc->sd_gpio) {
1562 		gpiod_set_value_cansleep(tc->sd_gpio, 0);
1563 		usleep_range(5000, 10000);
1564 	}
1565 
1566 	/* Reset GPIO is optional */
1567 	tc->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
1568 	if (IS_ERR(tc->reset_gpio))
1569 		return PTR_ERR(tc->reset_gpio);
1570 
1571 	if (tc->reset_gpio) {
1572 		gpiod_set_value_cansleep(tc->reset_gpio, 1);
1573 		usleep_range(5000, 10000);
1574 	}
1575 
1576 	tc->refclk = devm_clk_get(dev, "ref");
1577 	if (IS_ERR(tc->refclk)) {
1578 		ret = PTR_ERR(tc->refclk);
1579 		dev_err(dev, "Failed to get refclk: %d\n", ret);
1580 		return ret;
1581 	}
1582 
1583 	tc->regmap = devm_regmap_init_i2c(client, &tc_regmap_config);
1584 	if (IS_ERR(tc->regmap)) {
1585 		ret = PTR_ERR(tc->regmap);
1586 		dev_err(dev, "Failed to initialize regmap: %d\n", ret);
1587 		return ret;
1588 	}
1589 
1590 	ret = of_property_read_u32(dev->of_node, "toshiba,hpd-pin",
1591 				   &tc->hpd_pin);
1592 	if (ret) {
1593 		tc->hpd_pin = -ENODEV;
1594 	} else {
1595 		if (tc->hpd_pin < 0 || tc->hpd_pin > 1) {
1596 			dev_err(dev, "failed to parse HPD number\n");
1597 			return ret;
1598 		}
1599 	}
1600 
1601 	if (client->irq > 0) {
1602 		/* enable SysErr */
1603 		regmap_write(tc->regmap, INTCTL_G, INT_SYSERR);
1604 
1605 		ret = devm_request_threaded_irq(dev, client->irq,
1606 						NULL, tc_irq_handler,
1607 						IRQF_ONESHOT,
1608 						"tc358767-irq", tc);
1609 		if (ret) {
1610 			dev_err(dev, "failed to register dp interrupt\n");
1611 			return ret;
1612 		}
1613 
1614 		tc->have_irq = true;
1615 	}
1616 
1617 	ret = regmap_read(tc->regmap, TC_IDREG, &tc->rev);
1618 	if (ret) {
1619 		dev_err(tc->dev, "can not read device ID: %d\n", ret);
1620 		return ret;
1621 	}
1622 
1623 	if ((tc->rev != 0x6601) && (tc->rev != 0x6603)) {
1624 		dev_err(tc->dev, "invalid device ID: 0x%08x\n", tc->rev);
1625 		return -EINVAL;
1626 	}
1627 
1628 	tc->assr = (tc->rev == 0x6601); /* Enable ASSR for eDP panels */
1629 
1630 	if (!tc->reset_gpio) {
1631 		/*
1632 		 * If the reset pin isn't present, do a software reset. It isn't
1633 		 * as thorough as the hardware reset, as we can't reset the I2C
1634 		 * communication block for obvious reasons, but it's getting the
1635 		 * chip into a defined state.
1636 		 */
1637 		regmap_update_bits(tc->regmap, SYSRSTENB,
1638 				ENBLCD0 | ENBBM | ENBDSIRX | ENBREG | ENBHDCP,
1639 				0);
1640 		regmap_update_bits(tc->regmap, SYSRSTENB,
1641 				ENBLCD0 | ENBBM | ENBDSIRX | ENBREG | ENBHDCP,
1642 				ENBLCD0 | ENBBM | ENBDSIRX | ENBREG | ENBHDCP);
1643 		usleep_range(5000, 10000);
1644 	}
1645 
1646 	if (tc->hpd_pin >= 0) {
1647 		u32 lcnt_reg = tc->hpd_pin == 0 ? INT_GP0_LCNT : INT_GP1_LCNT;
1648 		u32 h_lc = INT_GPIO_H(tc->hpd_pin) | INT_GPIO_LC(tc->hpd_pin);
1649 
1650 		/* Set LCNT to 2ms */
1651 		regmap_write(tc->regmap, lcnt_reg,
1652 			     clk_get_rate(tc->refclk) * 2 / 1000);
1653 		/* We need the "alternate" mode for HPD */
1654 		regmap_write(tc->regmap, GPIOM, BIT(tc->hpd_pin));
1655 
1656 		if (tc->have_irq) {
1657 			/* enable H & LC */
1658 			regmap_update_bits(tc->regmap, INTCTL_G, h_lc, h_lc);
1659 		}
1660 	}
1661 
1662 	ret = tc_aux_link_setup(tc);
1663 	if (ret)
1664 		return ret;
1665 
1666 	/* Register DP AUX channel */
1667 	tc->aux.name = "TC358767 AUX i2c adapter";
1668 	tc->aux.dev = tc->dev;
1669 	tc->aux.transfer = tc_aux_transfer;
1670 	ret = drm_dp_aux_register(&tc->aux);
1671 	if (ret)
1672 		return ret;
1673 
1674 	tc->bridge.funcs = &tc_bridge_funcs;
1675 	tc->bridge.of_node = dev->of_node;
1676 	drm_bridge_add(&tc->bridge);
1677 
1678 	i2c_set_clientdata(client, tc);
1679 
1680 	return 0;
1681 }
1682 
1683 static int tc_remove(struct i2c_client *client)
1684 {
1685 	struct tc_data *tc = i2c_get_clientdata(client);
1686 
1687 	drm_bridge_remove(&tc->bridge);
1688 	drm_dp_aux_unregister(&tc->aux);
1689 
1690 	return 0;
1691 }
1692 
1693 static const struct i2c_device_id tc358767_i2c_ids[] = {
1694 	{ "tc358767", 0 },
1695 	{ }
1696 };
1697 MODULE_DEVICE_TABLE(i2c, tc358767_i2c_ids);
1698 
1699 static const struct of_device_id tc358767_of_ids[] = {
1700 	{ .compatible = "toshiba,tc358767", },
1701 	{ }
1702 };
1703 MODULE_DEVICE_TABLE(of, tc358767_of_ids);
1704 
1705 static struct i2c_driver tc358767_driver = {
1706 	.driver = {
1707 		.name = "tc358767",
1708 		.of_match_table = tc358767_of_ids,
1709 	},
1710 	.id_table = tc358767_i2c_ids,
1711 	.probe = tc_probe,
1712 	.remove	= tc_remove,
1713 };
1714 module_i2c_driver(tc358767_driver);
1715 
1716 MODULE_AUTHOR("Andrey Gusakov <andrey.gusakov@cogentembedded.com>");
1717 MODULE_DESCRIPTION("tc358767 eDP encoder driver");
1718 MODULE_LICENSE("GPL");
1719