xref: /linux/drivers/gpu/drm/bridge/tc358768.c (revision 79997eda0d31bc68203c95ecb978773ee6ce7a1f)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  Copyright (C) 2020 Texas Instruments Incorporated - https://www.ti.com
4  *  Author: Peter Ujfalusi <peter.ujfalusi@ti.com>
5  */
6 
7 #include <linux/clk.h>
8 #include <linux/device.h>
9 #include <linux/gpio/consumer.h>
10 #include <linux/i2c.h>
11 #include <linux/kernel.h>
12 #include <linux/math64.h>
13 #include <linux/media-bus-format.h>
14 #include <linux/minmax.h>
15 #include <linux/module.h>
16 #include <linux/regmap.h>
17 #include <linux/regulator/consumer.h>
18 #include <linux/slab.h>
19 #include <linux/units.h>
20 
21 #include <drm/drm_atomic_helper.h>
22 #include <drm/drm_drv.h>
23 #include <drm/drm_mipi_dsi.h>
24 #include <drm/drm_of.h>
25 #include <drm/drm_panel.h>
26 #include <video/mipi_display.h>
27 #include <video/videomode.h>
28 
29 /* Global (16-bit addressable) */
30 #define TC358768_CHIPID			0x0000
31 #define TC358768_SYSCTL			0x0002
32 #define TC358768_CONFCTL		0x0004
33 #define TC358768_VSDLY			0x0006
34 #define TC358768_DATAFMT		0x0008
35 #define TC358768_GPIOEN			0x000E
36 #define TC358768_GPIODIR		0x0010
37 #define TC358768_GPIOIN			0x0012
38 #define TC358768_GPIOOUT		0x0014
39 #define TC358768_PLLCTL0		0x0016
40 #define TC358768_PLLCTL1		0x0018
41 #define TC358768_CMDBYTE		0x0022
42 #define TC358768_PP_MISC		0x0032
43 #define TC358768_DSITX_DT		0x0050
44 #define TC358768_FIFOSTATUS		0x00F8
45 
46 /* Debug (16-bit addressable) */
47 #define TC358768_VBUFCTRL		0x00E0
48 #define TC358768_DBG_WIDTH		0x00E2
49 #define TC358768_DBG_VBLANK		0x00E4
50 #define TC358768_DBG_DATA		0x00E8
51 
52 /* TX PHY (32-bit addressable) */
53 #define TC358768_CLW_DPHYCONTTX		0x0100
54 #define TC358768_D0W_DPHYCONTTX		0x0104
55 #define TC358768_D1W_DPHYCONTTX		0x0108
56 #define TC358768_D2W_DPHYCONTTX		0x010C
57 #define TC358768_D3W_DPHYCONTTX		0x0110
58 #define TC358768_CLW_CNTRL		0x0140
59 #define TC358768_D0W_CNTRL		0x0144
60 #define TC358768_D1W_CNTRL		0x0148
61 #define TC358768_D2W_CNTRL		0x014C
62 #define TC358768_D3W_CNTRL		0x0150
63 
64 /* TX PPI (32-bit addressable) */
65 #define TC358768_STARTCNTRL		0x0204
66 #define TC358768_DSITXSTATUS		0x0208
67 #define TC358768_LINEINITCNT		0x0210
68 #define TC358768_LPTXTIMECNT		0x0214
69 #define TC358768_TCLK_HEADERCNT		0x0218
70 #define TC358768_TCLK_TRAILCNT		0x021C
71 #define TC358768_THS_HEADERCNT		0x0220
72 #define TC358768_TWAKEUP		0x0224
73 #define TC358768_TCLK_POSTCNT		0x0228
74 #define TC358768_THS_TRAILCNT		0x022C
75 #define TC358768_HSTXVREGCNT		0x0230
76 #define TC358768_HSTXVREGEN		0x0234
77 #define TC358768_TXOPTIONCNTRL		0x0238
78 #define TC358768_BTACNTRL1		0x023C
79 
80 /* TX CTRL (32-bit addressable) */
81 #define TC358768_DSI_CONTROL		0x040C
82 #define TC358768_DSI_STATUS		0x0410
83 #define TC358768_DSI_INT		0x0414
84 #define TC358768_DSI_INT_ENA		0x0418
85 #define TC358768_DSICMD_RDFIFO		0x0430
86 #define TC358768_DSI_ACKERR		0x0434
87 #define TC358768_DSI_ACKERR_INTENA	0x0438
88 #define TC358768_DSI_ACKERR_HALT	0x043c
89 #define TC358768_DSI_RXERR		0x0440
90 #define TC358768_DSI_RXERR_INTENA	0x0444
91 #define TC358768_DSI_RXERR_HALT		0x0448
92 #define TC358768_DSI_ERR		0x044C
93 #define TC358768_DSI_ERR_INTENA		0x0450
94 #define TC358768_DSI_ERR_HALT		0x0454
95 #define TC358768_DSI_CONFW		0x0500
96 #define TC358768_DSI_LPCMD		0x0500
97 #define TC358768_DSI_RESET		0x0504
98 #define TC358768_DSI_INT_CLR		0x050C
99 #define TC358768_DSI_START		0x0518
100 
101 /* DSITX CTRL (16-bit addressable) */
102 #define TC358768_DSICMD_TX		0x0600
103 #define TC358768_DSICMD_TYPE		0x0602
104 #define TC358768_DSICMD_WC		0x0604
105 #define TC358768_DSICMD_WD0		0x0610
106 #define TC358768_DSICMD_WD1		0x0612
107 #define TC358768_DSICMD_WD2		0x0614
108 #define TC358768_DSICMD_WD3		0x0616
109 #define TC358768_DSI_EVENT		0x0620
110 #define TC358768_DSI_VSW		0x0622
111 #define TC358768_DSI_VBPR		0x0624
112 #define TC358768_DSI_VACT		0x0626
113 #define TC358768_DSI_HSW		0x0628
114 #define TC358768_DSI_HBPR		0x062A
115 #define TC358768_DSI_HACT		0x062C
116 
117 /* TC358768_DSI_CONTROL (0x040C) register */
118 #define TC358768_DSI_CONTROL_DIS_MODE	BIT(15)
119 #define TC358768_DSI_CONTROL_TXMD	BIT(7)
120 #define TC358768_DSI_CONTROL_HSCKMD	BIT(5)
121 #define TC358768_DSI_CONTROL_EOTDIS	BIT(0)
122 
123 /* TC358768_DSI_CONFW (0x0500) register */
124 #define TC358768_DSI_CONFW_MODE_SET	(5 << 29)
125 #define TC358768_DSI_CONFW_MODE_CLR	(6 << 29)
126 #define TC358768_DSI_CONFW_ADDR_DSI_CONTROL	(0x3 << 24)
127 
128 static const char * const tc358768_supplies[] = {
129 	"vddc", "vddmipi", "vddio"
130 };
131 
132 struct tc358768_dsi_output {
133 	struct mipi_dsi_device *dev;
134 	struct drm_panel *panel;
135 	struct drm_bridge *bridge;
136 };
137 
138 struct tc358768_priv {
139 	struct device *dev;
140 	struct regmap *regmap;
141 	struct gpio_desc *reset_gpio;
142 	struct regulator_bulk_data supplies[ARRAY_SIZE(tc358768_supplies)];
143 	struct clk *refclk;
144 	int enabled;
145 	int error;
146 
147 	struct mipi_dsi_host dsi_host;
148 	struct drm_bridge bridge;
149 	struct tc358768_dsi_output output;
150 
151 	u32 pd_lines; /* number of Parallel Port Input Data Lines */
152 	u32 dsi_lanes; /* number of DSI Lanes */
153 	u32 dsi_bpp; /* number of Bits Per Pixel over DSI */
154 
155 	/* Parameters for PLL programming */
156 	u32 fbd;	/* PLL feedback divider */
157 	u32 prd;	/* PLL input divider */
158 	u32 frs;	/* PLL Freqency range for HSCK (post divider) */
159 
160 	u32 dsiclk;	/* pll_clk / 2 */
161 	u32 pclk;	/* incoming pclk rate */
162 };
163 
164 static inline struct tc358768_priv *dsi_host_to_tc358768(struct mipi_dsi_host
165 							 *host)
166 {
167 	return container_of(host, struct tc358768_priv, dsi_host);
168 }
169 
170 static inline struct tc358768_priv *bridge_to_tc358768(struct drm_bridge
171 						       *bridge)
172 {
173 	return container_of(bridge, struct tc358768_priv, bridge);
174 }
175 
176 static int tc358768_clear_error(struct tc358768_priv *priv)
177 {
178 	int ret = priv->error;
179 
180 	priv->error = 0;
181 	return ret;
182 }
183 
184 static void tc358768_write(struct tc358768_priv *priv, u32 reg, u32 val)
185 {
186 	/* work around https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81715 */
187 	int tmpval = val;
188 	size_t count = 2;
189 
190 	if (priv->error)
191 		return;
192 
193 	/* 16-bit register? */
194 	if (reg < 0x100 || reg >= 0x600)
195 		count = 1;
196 
197 	priv->error = regmap_bulk_write(priv->regmap, reg, &tmpval, count);
198 }
199 
200 static void tc358768_read(struct tc358768_priv *priv, u32 reg, u32 *val)
201 {
202 	size_t count = 2;
203 
204 	if (priv->error)
205 		return;
206 
207 	/* 16-bit register? */
208 	if (reg < 0x100 || reg >= 0x600) {
209 		*val = 0;
210 		count = 1;
211 	}
212 
213 	priv->error = regmap_bulk_read(priv->regmap, reg, val, count);
214 }
215 
216 static void tc358768_update_bits(struct tc358768_priv *priv, u32 reg, u32 mask,
217 				 u32 val)
218 {
219 	u32 tmp, orig;
220 
221 	tc358768_read(priv, reg, &orig);
222 
223 	if (priv->error)
224 		return;
225 
226 	tmp = orig & ~mask;
227 	tmp |= val & mask;
228 	if (tmp != orig)
229 		tc358768_write(priv, reg, tmp);
230 }
231 
232 static int tc358768_sw_reset(struct tc358768_priv *priv)
233 {
234 	/* Assert Reset */
235 	tc358768_write(priv, TC358768_SYSCTL, 1);
236 	/* Release Reset, Exit Sleep */
237 	tc358768_write(priv, TC358768_SYSCTL, 0);
238 
239 	return tc358768_clear_error(priv);
240 }
241 
242 static void tc358768_hw_enable(struct tc358768_priv *priv)
243 {
244 	int ret;
245 
246 	if (priv->enabled)
247 		return;
248 
249 	ret = clk_prepare_enable(priv->refclk);
250 	if (ret < 0)
251 		dev_err(priv->dev, "error enabling refclk (%d)\n", ret);
252 
253 	ret = regulator_bulk_enable(ARRAY_SIZE(priv->supplies), priv->supplies);
254 	if (ret < 0)
255 		dev_err(priv->dev, "error enabling regulators (%d)\n", ret);
256 
257 	if (priv->reset_gpio)
258 		usleep_range(200, 300);
259 
260 	/*
261 	 * The RESX is active low (GPIO_ACTIVE_LOW).
262 	 * DEASSERT (value = 0) the reset_gpio to enable the chip
263 	 */
264 	gpiod_set_value_cansleep(priv->reset_gpio, 0);
265 
266 	/* wait for encoder clocks to stabilize */
267 	usleep_range(1000, 2000);
268 
269 	priv->enabled = true;
270 }
271 
272 static void tc358768_hw_disable(struct tc358768_priv *priv)
273 {
274 	int ret;
275 
276 	if (!priv->enabled)
277 		return;
278 
279 	/*
280 	 * The RESX is active low (GPIO_ACTIVE_LOW).
281 	 * ASSERT (value = 1) the reset_gpio to disable the chip
282 	 */
283 	gpiod_set_value_cansleep(priv->reset_gpio, 1);
284 
285 	ret = regulator_bulk_disable(ARRAY_SIZE(priv->supplies),
286 				     priv->supplies);
287 	if (ret < 0)
288 		dev_err(priv->dev, "error disabling regulators (%d)\n", ret);
289 
290 	clk_disable_unprepare(priv->refclk);
291 
292 	priv->enabled = false;
293 }
294 
295 static u32 tc358768_pll_to_pclk(struct tc358768_priv *priv, u32 pll_clk)
296 {
297 	return (u32)div_u64((u64)pll_clk * priv->dsi_lanes, priv->dsi_bpp);
298 }
299 
300 static u32 tc358768_pclk_to_pll(struct tc358768_priv *priv, u32 pclk)
301 {
302 	return (u32)div_u64((u64)pclk * priv->dsi_bpp, priv->dsi_lanes);
303 }
304 
305 static int tc358768_calc_pll(struct tc358768_priv *priv,
306 			     const struct drm_display_mode *mode,
307 			     bool verify_only)
308 {
309 	static const u32 frs_limits[] = {
310 		1000000000,
311 		500000000,
312 		250000000,
313 		125000000,
314 		62500000
315 	};
316 	unsigned long refclk;
317 	u32 prd, target_pll, i, max_pll, min_pll;
318 	u32 frs, best_diff, best_pll, best_prd, best_fbd;
319 
320 	target_pll = tc358768_pclk_to_pll(priv, mode->clock * 1000);
321 
322 	/* pll_clk = RefClk * FBD / PRD * (1 / (2^FRS)) */
323 
324 	for (i = 0; i < ARRAY_SIZE(frs_limits); i++)
325 		if (target_pll >= frs_limits[i])
326 			break;
327 
328 	if (i == ARRAY_SIZE(frs_limits) || i == 0)
329 		return -EINVAL;
330 
331 	frs = i - 1;
332 	max_pll = frs_limits[i - 1];
333 	min_pll = frs_limits[i];
334 
335 	refclk = clk_get_rate(priv->refclk);
336 
337 	best_diff = UINT_MAX;
338 	best_pll = 0;
339 	best_prd = 0;
340 	best_fbd = 0;
341 
342 	for (prd = 1; prd <= 16; ++prd) {
343 		u32 divisor = prd * (1 << frs);
344 		u32 fbd;
345 
346 		for (fbd = 1; fbd <= 512; ++fbd) {
347 			u32 pll, diff, pll_in;
348 
349 			pll = (u32)div_u64((u64)refclk * fbd, divisor);
350 
351 			if (pll >= max_pll || pll < min_pll)
352 				continue;
353 
354 			pll_in = (u32)div_u64((u64)refclk, prd);
355 			if (pll_in < 4000000)
356 				continue;
357 
358 			diff = max(pll, target_pll) - min(pll, target_pll);
359 
360 			if (diff < best_diff) {
361 				best_diff = diff;
362 				best_pll = pll;
363 				best_prd = prd;
364 				best_fbd = fbd;
365 
366 				if (best_diff == 0)
367 					goto found;
368 			}
369 		}
370 	}
371 
372 	if (best_diff == UINT_MAX) {
373 		dev_err(priv->dev, "could not find suitable PLL setup\n");
374 		return -EINVAL;
375 	}
376 
377 found:
378 	if (verify_only)
379 		return 0;
380 
381 	priv->fbd = best_fbd;
382 	priv->prd = best_prd;
383 	priv->frs = frs;
384 	priv->dsiclk = best_pll / 2;
385 	priv->pclk = mode->clock * 1000;
386 
387 	return 0;
388 }
389 
390 static int tc358768_dsi_host_attach(struct mipi_dsi_host *host,
391 				    struct mipi_dsi_device *dev)
392 {
393 	struct tc358768_priv *priv = dsi_host_to_tc358768(host);
394 	struct drm_bridge *bridge;
395 	struct drm_panel *panel;
396 	struct device_node *ep;
397 	int ret;
398 
399 	if (dev->lanes > 4) {
400 		dev_err(priv->dev, "unsupported number of data lanes(%u)\n",
401 			dev->lanes);
402 		return -EINVAL;
403 	}
404 
405 	/*
406 	 * tc358768 supports both Video and Pulse mode, but the driver only
407 	 * implements Video (event) mode currently
408 	 */
409 	if (!(dev->mode_flags & MIPI_DSI_MODE_VIDEO)) {
410 		dev_err(priv->dev, "Only MIPI_DSI_MODE_VIDEO is supported\n");
411 		return -ENOTSUPP;
412 	}
413 
414 	/*
415 	 * tc358768 supports RGB888, RGB666, RGB666_PACKED and RGB565, but only
416 	 * RGB888 is verified.
417 	 */
418 	if (dev->format != MIPI_DSI_FMT_RGB888) {
419 		dev_warn(priv->dev, "Only MIPI_DSI_FMT_RGB888 tested!\n");
420 		return -ENOTSUPP;
421 	}
422 
423 	ret = drm_of_find_panel_or_bridge(host->dev->of_node, 1, 0, &panel,
424 					  &bridge);
425 	if (ret)
426 		return ret;
427 
428 	if (panel) {
429 		bridge = drm_panel_bridge_add_typed(panel,
430 						    DRM_MODE_CONNECTOR_DSI);
431 		if (IS_ERR(bridge))
432 			return PTR_ERR(bridge);
433 	}
434 
435 	priv->output.dev = dev;
436 	priv->output.bridge = bridge;
437 	priv->output.panel = panel;
438 
439 	priv->dsi_lanes = dev->lanes;
440 	priv->dsi_bpp = mipi_dsi_pixel_format_to_bpp(dev->format);
441 
442 	/* get input ep (port0/endpoint0) */
443 	ret = -EINVAL;
444 	ep = of_graph_get_endpoint_by_regs(host->dev->of_node, 0, 0);
445 	if (ep) {
446 		ret = of_property_read_u32(ep, "data-lines", &priv->pd_lines);
447 
448 		of_node_put(ep);
449 	}
450 
451 	if (ret)
452 		priv->pd_lines = priv->dsi_bpp;
453 
454 	drm_bridge_add(&priv->bridge);
455 
456 	return 0;
457 }
458 
459 static int tc358768_dsi_host_detach(struct mipi_dsi_host *host,
460 				    struct mipi_dsi_device *dev)
461 {
462 	struct tc358768_priv *priv = dsi_host_to_tc358768(host);
463 
464 	drm_bridge_remove(&priv->bridge);
465 	if (priv->output.panel)
466 		drm_panel_bridge_remove(priv->output.bridge);
467 
468 	return 0;
469 }
470 
471 static ssize_t tc358768_dsi_host_transfer(struct mipi_dsi_host *host,
472 					  const struct mipi_dsi_msg *msg)
473 {
474 	struct tc358768_priv *priv = dsi_host_to_tc358768(host);
475 	struct mipi_dsi_packet packet;
476 	int ret;
477 
478 	if (!priv->enabled) {
479 		dev_err(priv->dev, "Bridge is not enabled\n");
480 		return -ENODEV;
481 	}
482 
483 	if (msg->rx_len) {
484 		dev_warn(priv->dev, "MIPI rx is not supported\n");
485 		return -ENOTSUPP;
486 	}
487 
488 	if (msg->tx_len > 8) {
489 		dev_warn(priv->dev, "Maximum 8 byte MIPI tx is supported\n");
490 		return -ENOTSUPP;
491 	}
492 
493 	ret = mipi_dsi_create_packet(&packet, msg);
494 	if (ret)
495 		return ret;
496 
497 	if (mipi_dsi_packet_format_is_short(msg->type)) {
498 		tc358768_write(priv, TC358768_DSICMD_TYPE,
499 			       (0x10 << 8) | (packet.header[0] & 0x3f));
500 		tc358768_write(priv, TC358768_DSICMD_WC, 0);
501 		tc358768_write(priv, TC358768_DSICMD_WD0,
502 			       (packet.header[2] << 8) | packet.header[1]);
503 	} else {
504 		int i;
505 
506 		tc358768_write(priv, TC358768_DSICMD_TYPE,
507 			       (0x40 << 8) | (packet.header[0] & 0x3f));
508 		tc358768_write(priv, TC358768_DSICMD_WC, packet.payload_length);
509 		for (i = 0; i < packet.payload_length; i += 2) {
510 			u16 val = packet.payload[i];
511 
512 			if (i + 1 < packet.payload_length)
513 				val |= packet.payload[i + 1] << 8;
514 
515 			tc358768_write(priv, TC358768_DSICMD_WD0 + i, val);
516 		}
517 	}
518 
519 	/* start transfer */
520 	tc358768_write(priv, TC358768_DSICMD_TX, 1);
521 
522 	ret = tc358768_clear_error(priv);
523 	if (ret)
524 		dev_warn(priv->dev, "Software disable failed: %d\n", ret);
525 	else
526 		ret = packet.size;
527 
528 	return ret;
529 }
530 
531 static const struct mipi_dsi_host_ops tc358768_dsi_host_ops = {
532 	.attach = tc358768_dsi_host_attach,
533 	.detach = tc358768_dsi_host_detach,
534 	.transfer = tc358768_dsi_host_transfer,
535 };
536 
537 static int tc358768_bridge_attach(struct drm_bridge *bridge,
538 				  enum drm_bridge_attach_flags flags)
539 {
540 	struct tc358768_priv *priv = bridge_to_tc358768(bridge);
541 
542 	if (!drm_core_check_feature(bridge->dev, DRIVER_ATOMIC)) {
543 		dev_err(priv->dev, "needs atomic updates support\n");
544 		return -ENOTSUPP;
545 	}
546 
547 	return drm_bridge_attach(bridge->encoder, priv->output.bridge, bridge,
548 				 flags);
549 }
550 
551 static enum drm_mode_status
552 tc358768_bridge_mode_valid(struct drm_bridge *bridge,
553 			   const struct drm_display_info *info,
554 			   const struct drm_display_mode *mode)
555 {
556 	struct tc358768_priv *priv = bridge_to_tc358768(bridge);
557 
558 	if (tc358768_calc_pll(priv, mode, true))
559 		return MODE_CLOCK_RANGE;
560 
561 	return MODE_OK;
562 }
563 
564 static void tc358768_bridge_disable(struct drm_bridge *bridge)
565 {
566 	struct tc358768_priv *priv = bridge_to_tc358768(bridge);
567 	int ret;
568 
569 	/* set FrmStop */
570 	tc358768_update_bits(priv, TC358768_PP_MISC, BIT(15), BIT(15));
571 
572 	/* wait at least for one frame */
573 	msleep(50);
574 
575 	/* clear PP_en */
576 	tc358768_update_bits(priv, TC358768_CONFCTL, BIT(6), 0);
577 
578 	/* set RstPtr */
579 	tc358768_update_bits(priv, TC358768_PP_MISC, BIT(14), BIT(14));
580 
581 	ret = tc358768_clear_error(priv);
582 	if (ret)
583 		dev_warn(priv->dev, "Software disable failed: %d\n", ret);
584 }
585 
586 static void tc358768_bridge_post_disable(struct drm_bridge *bridge)
587 {
588 	struct tc358768_priv *priv = bridge_to_tc358768(bridge);
589 
590 	tc358768_hw_disable(priv);
591 }
592 
593 static int tc358768_setup_pll(struct tc358768_priv *priv,
594 			      const struct drm_display_mode *mode)
595 {
596 	u32 fbd, prd, frs;
597 	int ret;
598 
599 	ret = tc358768_calc_pll(priv, mode, false);
600 	if (ret) {
601 		dev_err(priv->dev, "PLL calculation failed: %d\n", ret);
602 		return ret;
603 	}
604 
605 	fbd = priv->fbd;
606 	prd = priv->prd;
607 	frs = priv->frs;
608 
609 	dev_dbg(priv->dev, "PLL: refclk %lu, fbd %u, prd %u, frs %u\n",
610 		clk_get_rate(priv->refclk), fbd, prd, frs);
611 	dev_dbg(priv->dev, "PLL: pll_clk: %u, DSIClk %u, HSByteClk %u\n",
612 		priv->dsiclk * 2, priv->dsiclk, priv->dsiclk / 4);
613 	dev_dbg(priv->dev, "PLL: pclk %u (panel: %u)\n",
614 		tc358768_pll_to_pclk(priv, priv->dsiclk * 2),
615 		mode->clock * 1000);
616 
617 	/* PRD[15:12] FBD[8:0] */
618 	tc358768_write(priv, TC358768_PLLCTL0, ((prd - 1) << 12) | (fbd - 1));
619 
620 	/* FRS[11:10] LBWS[9:8] CKEN[4] RESETB[1] EN[0] */
621 	tc358768_write(priv, TC358768_PLLCTL1,
622 		       (frs << 10) | (0x2 << 8) | BIT(1) | BIT(0));
623 
624 	/* wait for lock */
625 	usleep_range(1000, 2000);
626 
627 	/* FRS[11:10] LBWS[9:8] CKEN[4] PLL_CKEN[4] RESETB[1] EN[0] */
628 	tc358768_write(priv, TC358768_PLLCTL1,
629 		       (frs << 10) | (0x2 << 8) | BIT(4) | BIT(1) | BIT(0));
630 
631 	return tc358768_clear_error(priv);
632 }
633 
634 static u32 tc358768_ns_to_cnt(u32 ns, u32 period_ps)
635 {
636 	return DIV_ROUND_UP(ns * 1000, period_ps);
637 }
638 
639 static u32 tc358768_ps_to_ns(u32 ps)
640 {
641 	return ps / 1000;
642 }
643 
644 static u32 tc358768_dpi_to_ns(u32 val, u32 pclk)
645 {
646 	return (u32)div_u64((u64)val * NANO, pclk);
647 }
648 
649 /* Convert value in DPI pixel clock units to DSI byte count */
650 static u32 tc358768_dpi_to_dsi_bytes(struct tc358768_priv *priv, u32 val)
651 {
652 	u64 m = (u64)val * priv->dsiclk / 4 * priv->dsi_lanes;
653 	u64 n = priv->pclk;
654 
655 	return (u32)div_u64(m + n - 1, n);
656 }
657 
658 static u32 tc358768_dsi_bytes_to_ns(struct tc358768_priv *priv, u32 val)
659 {
660 	u64 m = (u64)val * NANO;
661 	u64 n = priv->dsiclk / 4 * priv->dsi_lanes;
662 
663 	return (u32)div_u64(m, n);
664 }
665 
666 static void tc358768_bridge_pre_enable(struct drm_bridge *bridge)
667 {
668 	struct tc358768_priv *priv = bridge_to_tc358768(bridge);
669 	struct mipi_dsi_device *dsi_dev = priv->output.dev;
670 	unsigned long mode_flags = dsi_dev->mode_flags;
671 	u32 val, val2, lptxcnt, hact, data_type;
672 	s32 raw_val;
673 	const struct drm_display_mode *mode;
674 	u32 hsbyteclk_ps, dsiclk_ps, ui_ps;
675 	u32 dsiclk, hsbyteclk;
676 	int ret, i;
677 	struct videomode vm;
678 	struct device *dev = priv->dev;
679 	/* In pixelclock units */
680 	u32 dpi_htot, dpi_data_start;
681 	/* In byte units */
682 	u32 dsi_dpi_htot, dsi_dpi_data_start;
683 	u32 dsi_hsw, dsi_hbp, dsi_hact, dsi_hfp;
684 	const u32 dsi_hss = 4; /* HSS is a short packet (4 bytes) */
685 	/* In hsbyteclk units */
686 	u32 dsi_vsdly;
687 	const u32 internal_dly = 40;
688 
689 	if (mode_flags & MIPI_DSI_CLOCK_NON_CONTINUOUS) {
690 		dev_warn_once(dev, "Non-continuous mode unimplemented, falling back to continuous\n");
691 		mode_flags &= ~MIPI_DSI_CLOCK_NON_CONTINUOUS;
692 	}
693 
694 	tc358768_hw_enable(priv);
695 
696 	ret = tc358768_sw_reset(priv);
697 	if (ret) {
698 		dev_err(dev, "Software reset failed: %d\n", ret);
699 		tc358768_hw_disable(priv);
700 		return;
701 	}
702 
703 	mode = &bridge->encoder->crtc->state->adjusted_mode;
704 	ret = tc358768_setup_pll(priv, mode);
705 	if (ret) {
706 		dev_err(dev, "PLL setup failed: %d\n", ret);
707 		tc358768_hw_disable(priv);
708 		return;
709 	}
710 
711 	drm_display_mode_to_videomode(mode, &vm);
712 
713 	dsiclk = priv->dsiclk;
714 	hsbyteclk = dsiclk / 4;
715 
716 	/* Data Format Control Register */
717 	val = BIT(2) | BIT(1) | BIT(0); /* rdswap_en | dsitx_en | txdt_en */
718 	switch (dsi_dev->format) {
719 	case MIPI_DSI_FMT_RGB888:
720 		val |= (0x3 << 4);
721 		hact = vm.hactive * 3;
722 		data_type = MIPI_DSI_PACKED_PIXEL_STREAM_24;
723 		break;
724 	case MIPI_DSI_FMT_RGB666:
725 		val |= (0x4 << 4);
726 		hact = vm.hactive * 3;
727 		data_type = MIPI_DSI_PACKED_PIXEL_STREAM_18;
728 		break;
729 
730 	case MIPI_DSI_FMT_RGB666_PACKED:
731 		val |= (0x4 << 4) | BIT(3);
732 		hact = vm.hactive * 18 / 8;
733 		data_type = MIPI_DSI_PIXEL_STREAM_3BYTE_18;
734 		break;
735 
736 	case MIPI_DSI_FMT_RGB565:
737 		val |= (0x5 << 4);
738 		hact = vm.hactive * 2;
739 		data_type = MIPI_DSI_PACKED_PIXEL_STREAM_16;
740 		break;
741 	default:
742 		dev_err(dev, "Invalid data format (%u)\n",
743 			dsi_dev->format);
744 		tc358768_hw_disable(priv);
745 		return;
746 	}
747 
748 	/*
749 	 * There are three important things to make TC358768 work correctly,
750 	 * which are not trivial to manage:
751 	 *
752 	 * 1. Keep the DPI line-time and the DSI line-time as close to each
753 	 *    other as possible.
754 	 * 2. TC358768 goes to LP mode after each line's active area. The DSI
755 	 *    HFP period has to be long enough for entering and exiting LP mode.
756 	 *    But it is not clear how to calculate this.
757 	 * 3. VSDly (video start delay) has to be long enough to ensure that the
758 	 *    DSI TX does not start transmitting until we have started receiving
759 	 *    pixel data from the DPI input. It is not clear how to calculate
760 	 *    this either.
761 	 */
762 
763 	dpi_htot = vm.hactive + vm.hfront_porch + vm.hsync_len + vm.hback_porch;
764 	dpi_data_start = vm.hsync_len + vm.hback_porch;
765 
766 	dev_dbg(dev, "dpi horiz timing (pclk): %u + %u + %u + %u = %u\n",
767 		vm.hsync_len, vm.hback_porch, vm.hactive, vm.hfront_porch,
768 		dpi_htot);
769 
770 	dev_dbg(dev, "dpi horiz timing (ns): %u + %u + %u + %u = %u\n",
771 		tc358768_dpi_to_ns(vm.hsync_len, vm.pixelclock),
772 		tc358768_dpi_to_ns(vm.hback_porch, vm.pixelclock),
773 		tc358768_dpi_to_ns(vm.hactive, vm.pixelclock),
774 		tc358768_dpi_to_ns(vm.hfront_porch, vm.pixelclock),
775 		tc358768_dpi_to_ns(dpi_htot, vm.pixelclock));
776 
777 	dev_dbg(dev, "dpi data start (ns): %u + %u = %u\n",
778 		tc358768_dpi_to_ns(vm.hsync_len, vm.pixelclock),
779 		tc358768_dpi_to_ns(vm.hback_porch, vm.pixelclock),
780 		tc358768_dpi_to_ns(dpi_data_start, vm.pixelclock));
781 
782 	dsi_dpi_htot = tc358768_dpi_to_dsi_bytes(priv, dpi_htot);
783 	dsi_dpi_data_start = tc358768_dpi_to_dsi_bytes(priv, dpi_data_start);
784 
785 	if (dsi_dev->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE) {
786 		dsi_hsw = tc358768_dpi_to_dsi_bytes(priv, vm.hsync_len);
787 		dsi_hbp = tc358768_dpi_to_dsi_bytes(priv, vm.hback_porch);
788 	} else {
789 		/* HBP is included in HSW in event mode */
790 		dsi_hbp = 0;
791 		dsi_hsw = tc358768_dpi_to_dsi_bytes(priv,
792 						    vm.hsync_len +
793 						    vm.hback_porch);
794 
795 		/*
796 		 * The pixel packet includes the actual pixel data, and:
797 		 * DSI packet header = 4 bytes
798 		 * DCS code = 1 byte
799 		 * DSI packet footer = 2 bytes
800 		 */
801 		dsi_hact = hact + 4 + 1 + 2;
802 
803 		dsi_hfp = dsi_dpi_htot - dsi_hact - dsi_hsw - dsi_hss;
804 
805 		/*
806 		 * Here we should check if HFP is long enough for entering LP
807 		 * and exiting LP, but it's not clear how to calculate that.
808 		 * Instead, this is a naive algorithm that just adjusts the HFP
809 		 * and HSW so that HFP is (at least) roughly 2/3 of the total
810 		 * blanking time.
811 		 */
812 		if (dsi_hfp < (dsi_hfp + dsi_hsw + dsi_hss) * 2 / 3) {
813 			u32 old_hfp = dsi_hfp;
814 			u32 old_hsw = dsi_hsw;
815 			u32 tot = dsi_hfp + dsi_hsw + dsi_hss;
816 
817 			dsi_hsw = tot / 3;
818 
819 			/*
820 			 * Seems like sometimes HSW has to be divisible by num-lanes, but
821 			 * not always...
822 			 */
823 			dsi_hsw = roundup(dsi_hsw, priv->dsi_lanes);
824 
825 			dsi_hfp = dsi_dpi_htot - dsi_hact - dsi_hsw - dsi_hss;
826 
827 			dev_dbg(dev,
828 				"hfp too short, adjusting dsi hfp and dsi hsw from %u, %u to %u, %u\n",
829 				old_hfp, old_hsw, dsi_hfp, dsi_hsw);
830 		}
831 
832 		dev_dbg(dev,
833 			"dsi horiz timing (bytes): %u, %u + %u + %u + %u = %u\n",
834 			dsi_hss, dsi_hsw, dsi_hbp, dsi_hact, dsi_hfp,
835 			dsi_hss + dsi_hsw + dsi_hbp + dsi_hact + dsi_hfp);
836 
837 		dev_dbg(dev, "dsi horiz timing (ns): %u + %u + %u + %u + %u = %u\n",
838 			tc358768_dsi_bytes_to_ns(priv, dsi_hss),
839 			tc358768_dsi_bytes_to_ns(priv, dsi_hsw),
840 			tc358768_dsi_bytes_to_ns(priv, dsi_hbp),
841 			tc358768_dsi_bytes_to_ns(priv, dsi_hact),
842 			tc358768_dsi_bytes_to_ns(priv, dsi_hfp),
843 			tc358768_dsi_bytes_to_ns(priv, dsi_hss + dsi_hsw +
844 						 dsi_hbp + dsi_hact + dsi_hfp));
845 	}
846 
847 	/* VSDly calculation */
848 
849 	/* Start with the HW internal delay */
850 	dsi_vsdly = internal_dly;
851 
852 	/* Convert to byte units as the other variables are in byte units */
853 	dsi_vsdly *= priv->dsi_lanes;
854 
855 	/* Do we need more delay, in addition to the internal? */
856 	if (dsi_dpi_data_start > dsi_vsdly + dsi_hss + dsi_hsw + dsi_hbp) {
857 		dsi_vsdly = dsi_dpi_data_start - dsi_hss - dsi_hsw - dsi_hbp;
858 		dsi_vsdly = roundup(dsi_vsdly, priv->dsi_lanes);
859 	}
860 
861 	dev_dbg(dev, "dsi data start (bytes) %u + %u + %u + %u = %u\n",
862 		dsi_vsdly, dsi_hss, dsi_hsw, dsi_hbp,
863 		dsi_vsdly + dsi_hss + dsi_hsw + dsi_hbp);
864 
865 	dev_dbg(dev, "dsi data start (ns) %u + %u + %u + %u = %u\n",
866 		tc358768_dsi_bytes_to_ns(priv, dsi_vsdly),
867 		tc358768_dsi_bytes_to_ns(priv, dsi_hss),
868 		tc358768_dsi_bytes_to_ns(priv, dsi_hsw),
869 		tc358768_dsi_bytes_to_ns(priv, dsi_hbp),
870 		tc358768_dsi_bytes_to_ns(priv, dsi_vsdly + dsi_hss + dsi_hsw + dsi_hbp));
871 
872 	/* Convert back to hsbyteclk */
873 	dsi_vsdly /= priv->dsi_lanes;
874 
875 	/*
876 	 * The docs say that there is an internal delay of 40 cycles.
877 	 * However, we get underflows if we follow that rule. If we
878 	 * instead ignore the internal delay, things work. So either
879 	 * the docs are wrong or the calculations are wrong.
880 	 *
881 	 * As a temporary fix, add the internal delay here, to counter
882 	 * the subtraction when writing the register.
883 	 */
884 	dsi_vsdly += internal_dly;
885 
886 	/* Clamp to the register max */
887 	if (dsi_vsdly - internal_dly > 0x3ff) {
888 		dev_warn(dev, "VSDly too high, underflows likely\n");
889 		dsi_vsdly = 0x3ff + internal_dly;
890 	}
891 
892 	/* VSDly[9:0] */
893 	tc358768_write(priv, TC358768_VSDLY, dsi_vsdly - internal_dly);
894 
895 	tc358768_write(priv, TC358768_DATAFMT, val);
896 	tc358768_write(priv, TC358768_DSITX_DT, data_type);
897 
898 	/* Enable D-PHY (HiZ->LP11) */
899 	tc358768_write(priv, TC358768_CLW_CNTRL, 0x0000);
900 	/* Enable lanes */
901 	for (i = 0; i < dsi_dev->lanes; i++)
902 		tc358768_write(priv, TC358768_D0W_CNTRL + i * 4, 0x0000);
903 
904 	/* DSI Timings */
905 	hsbyteclk_ps = (u32)div_u64(PICO, hsbyteclk);
906 	dsiclk_ps = (u32)div_u64(PICO, dsiclk);
907 	ui_ps = dsiclk_ps / 2;
908 	dev_dbg(dev, "dsiclk: %u ps, ui %u ps, hsbyteclk %u ps\n", dsiclk_ps,
909 		ui_ps, hsbyteclk_ps);
910 
911 	/* LP11 > 100us for D-PHY Rx Init */
912 	val = tc358768_ns_to_cnt(100 * 1000, hsbyteclk_ps) - 1;
913 	dev_dbg(dev, "LINEINITCNT: %u\n", val);
914 	tc358768_write(priv, TC358768_LINEINITCNT, val);
915 
916 	/* LPTimeCnt > 50ns */
917 	val = tc358768_ns_to_cnt(50, hsbyteclk_ps) - 1;
918 	lptxcnt = val;
919 	dev_dbg(dev, "LPTXTIMECNT: %u\n", val);
920 	tc358768_write(priv, TC358768_LPTXTIMECNT, val);
921 
922 	/* 38ns < TCLK_PREPARE < 95ns */
923 	val = tc358768_ns_to_cnt(65, hsbyteclk_ps) - 1;
924 	dev_dbg(dev, "TCLK_PREPARECNT %u\n", val);
925 	/* TCLK_PREPARE + TCLK_ZERO > 300ns */
926 	val2 = tc358768_ns_to_cnt(300 - tc358768_ps_to_ns(2 * ui_ps),
927 				  hsbyteclk_ps) - 2;
928 	dev_dbg(dev, "TCLK_ZEROCNT %u\n", val2);
929 	val |= val2 << 8;
930 	tc358768_write(priv, TC358768_TCLK_HEADERCNT, val);
931 
932 	/* TCLK_TRAIL > 60ns AND TEOT <= 105 ns + 12*UI */
933 	raw_val = tc358768_ns_to_cnt(60 + tc358768_ps_to_ns(2 * ui_ps), hsbyteclk_ps) - 5;
934 	val = clamp(raw_val, 0, 127);
935 	dev_dbg(dev, "TCLK_TRAILCNT: %u\n", val);
936 	tc358768_write(priv, TC358768_TCLK_TRAILCNT, val);
937 
938 	/* 40ns + 4*UI < THS_PREPARE < 85ns + 6*UI */
939 	val = 50 + tc358768_ps_to_ns(4 * ui_ps);
940 	val = tc358768_ns_to_cnt(val, hsbyteclk_ps) - 1;
941 	dev_dbg(dev, "THS_PREPARECNT %u\n", val);
942 	/* THS_PREPARE + THS_ZERO > 145ns + 10*UI */
943 	raw_val = tc358768_ns_to_cnt(145 - tc358768_ps_to_ns(3 * ui_ps), hsbyteclk_ps) - 10;
944 	val2 = clamp(raw_val, 0, 127);
945 	dev_dbg(dev, "THS_ZEROCNT %u\n", val2);
946 	val |= val2 << 8;
947 	tc358768_write(priv, TC358768_THS_HEADERCNT, val);
948 
949 	/* TWAKEUP > 1ms in lptxcnt steps */
950 	val = tc358768_ns_to_cnt(1020000, hsbyteclk_ps);
951 	val = val / (lptxcnt + 1) - 1;
952 	dev_dbg(dev, "TWAKEUP: %u\n", val);
953 	tc358768_write(priv, TC358768_TWAKEUP, val);
954 
955 	/* TCLK_POSTCNT > 60ns + 52*UI */
956 	val = tc358768_ns_to_cnt(60 + tc358768_ps_to_ns(52 * ui_ps),
957 				 hsbyteclk_ps) - 3;
958 	dev_dbg(dev, "TCLK_POSTCNT: %u\n", val);
959 	tc358768_write(priv, TC358768_TCLK_POSTCNT, val);
960 
961 	/* max(60ns + 4*UI, 8*UI) < THS_TRAILCNT < 105ns + 12*UI */
962 	raw_val = tc358768_ns_to_cnt(60 + tc358768_ps_to_ns(18 * ui_ps),
963 				     hsbyteclk_ps) - 4;
964 	val = clamp(raw_val, 0, 15);
965 	dev_dbg(dev, "THS_TRAILCNT: %u\n", val);
966 	tc358768_write(priv, TC358768_THS_TRAILCNT, val);
967 
968 	val = BIT(0);
969 	for (i = 0; i < dsi_dev->lanes; i++)
970 		val |= BIT(i + 1);
971 	tc358768_write(priv, TC358768_HSTXVREGEN, val);
972 
973 	tc358768_write(priv, TC358768_TXOPTIONCNTRL,
974 		       (mode_flags & MIPI_DSI_CLOCK_NON_CONTINUOUS) ? 0 : BIT(0));
975 
976 	/* TXTAGOCNT[26:16] RXTASURECNT[10:0] */
977 	val = tc358768_ps_to_ns((lptxcnt + 1) * hsbyteclk_ps * 4);
978 	val = tc358768_ns_to_cnt(val, hsbyteclk_ps) / 4 - 1;
979 	dev_dbg(dev, "TXTAGOCNT: %u\n", val);
980 	val2 = tc358768_ns_to_cnt(tc358768_ps_to_ns((lptxcnt + 1) * hsbyteclk_ps),
981 				  hsbyteclk_ps) - 2;
982 	dev_dbg(dev, "RXTASURECNT: %u\n", val2);
983 	val = val << 16 | val2;
984 	tc358768_write(priv, TC358768_BTACNTRL1, val);
985 
986 	/* START[0] */
987 	tc358768_write(priv, TC358768_STARTCNTRL, 1);
988 
989 	if (dsi_dev->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE) {
990 		/* Set pulse mode */
991 		tc358768_write(priv, TC358768_DSI_EVENT, 0);
992 
993 		/* vact */
994 		tc358768_write(priv, TC358768_DSI_VACT, vm.vactive);
995 
996 		/* vsw */
997 		tc358768_write(priv, TC358768_DSI_VSW, vm.vsync_len);
998 
999 		/* vbp */
1000 		tc358768_write(priv, TC358768_DSI_VBPR, vm.vback_porch);
1001 	} else {
1002 		/* Set event mode */
1003 		tc358768_write(priv, TC358768_DSI_EVENT, 1);
1004 
1005 		/* vact */
1006 		tc358768_write(priv, TC358768_DSI_VACT, vm.vactive);
1007 
1008 		/* vsw (+ vbp) */
1009 		tc358768_write(priv, TC358768_DSI_VSW,
1010 			       vm.vsync_len + vm.vback_porch);
1011 
1012 		/* vbp (not used in event mode) */
1013 		tc358768_write(priv, TC358768_DSI_VBPR, 0);
1014 	}
1015 
1016 	/* hsw (bytes) */
1017 	tc358768_write(priv, TC358768_DSI_HSW, dsi_hsw);
1018 
1019 	/* hbp (bytes) */
1020 	tc358768_write(priv, TC358768_DSI_HBPR, dsi_hbp);
1021 
1022 	/* hact (bytes) */
1023 	tc358768_write(priv, TC358768_DSI_HACT, hact);
1024 
1025 	/* VSYNC polarity */
1026 	tc358768_update_bits(priv, TC358768_CONFCTL, BIT(5),
1027 			     (mode->flags & DRM_MODE_FLAG_PVSYNC) ? BIT(5) : 0);
1028 
1029 	/* HSYNC polarity */
1030 	tc358768_update_bits(priv, TC358768_PP_MISC, BIT(0),
1031 			     (mode->flags & DRM_MODE_FLAG_PHSYNC) ? BIT(0) : 0);
1032 
1033 	/* Start DSI Tx */
1034 	tc358768_write(priv, TC358768_DSI_START, 0x1);
1035 
1036 	/* Configure DSI_Control register */
1037 	val = TC358768_DSI_CONFW_MODE_CLR | TC358768_DSI_CONFW_ADDR_DSI_CONTROL;
1038 	val |= TC358768_DSI_CONTROL_TXMD | TC358768_DSI_CONTROL_HSCKMD |
1039 	       0x3 << 1 | TC358768_DSI_CONTROL_EOTDIS;
1040 	tc358768_write(priv, TC358768_DSI_CONFW, val);
1041 
1042 	val = TC358768_DSI_CONFW_MODE_SET | TC358768_DSI_CONFW_ADDR_DSI_CONTROL;
1043 	val |= (dsi_dev->lanes - 1) << 1;
1044 
1045 	val |= TC358768_DSI_CONTROL_TXMD;
1046 
1047 	if (!(mode_flags & MIPI_DSI_CLOCK_NON_CONTINUOUS))
1048 		val |= TC358768_DSI_CONTROL_HSCKMD;
1049 
1050 	if (dsi_dev->mode_flags & MIPI_DSI_MODE_NO_EOT_PACKET)
1051 		val |= TC358768_DSI_CONTROL_EOTDIS;
1052 
1053 	tc358768_write(priv, TC358768_DSI_CONFW, val);
1054 
1055 	val = TC358768_DSI_CONFW_MODE_CLR | TC358768_DSI_CONFW_ADDR_DSI_CONTROL;
1056 	val |= TC358768_DSI_CONTROL_DIS_MODE; /* DSI mode */
1057 	tc358768_write(priv, TC358768_DSI_CONFW, val);
1058 
1059 	ret = tc358768_clear_error(priv);
1060 	if (ret) {
1061 		dev_err(dev, "Bridge pre_enable failed: %d\n", ret);
1062 		tc358768_bridge_disable(bridge);
1063 		tc358768_bridge_post_disable(bridge);
1064 	}
1065 }
1066 
1067 static void tc358768_bridge_enable(struct drm_bridge *bridge)
1068 {
1069 	struct tc358768_priv *priv = bridge_to_tc358768(bridge);
1070 	int ret;
1071 
1072 	if (!priv->enabled) {
1073 		dev_err(priv->dev, "Bridge is not enabled\n");
1074 		return;
1075 	}
1076 
1077 	/* clear FrmStop and RstPtr */
1078 	tc358768_update_bits(priv, TC358768_PP_MISC, 0x3 << 14, 0);
1079 
1080 	/* set PP_en */
1081 	tc358768_update_bits(priv, TC358768_CONFCTL, BIT(6), BIT(6));
1082 
1083 	ret = tc358768_clear_error(priv);
1084 	if (ret) {
1085 		dev_err(priv->dev, "Bridge enable failed: %d\n", ret);
1086 		tc358768_bridge_disable(bridge);
1087 		tc358768_bridge_post_disable(bridge);
1088 	}
1089 }
1090 
1091 #define MAX_INPUT_SEL_FORMATS	1
1092 
1093 static u32 *
1094 tc358768_atomic_get_input_bus_fmts(struct drm_bridge *bridge,
1095 				   struct drm_bridge_state *bridge_state,
1096 				   struct drm_crtc_state *crtc_state,
1097 				   struct drm_connector_state *conn_state,
1098 				   u32 output_fmt,
1099 				   unsigned int *num_input_fmts)
1100 {
1101 	struct tc358768_priv *priv = bridge_to_tc358768(bridge);
1102 	u32 *input_fmts;
1103 
1104 	*num_input_fmts = 0;
1105 
1106 	input_fmts = kcalloc(MAX_INPUT_SEL_FORMATS, sizeof(*input_fmts),
1107 			     GFP_KERNEL);
1108 	if (!input_fmts)
1109 		return NULL;
1110 
1111 	switch (priv->pd_lines) {
1112 	case 16:
1113 		input_fmts[0] = MEDIA_BUS_FMT_RGB565_1X16;
1114 		break;
1115 	case 18:
1116 		input_fmts[0] = MEDIA_BUS_FMT_RGB666_1X18;
1117 		break;
1118 	default:
1119 	case 24:
1120 		input_fmts[0] = MEDIA_BUS_FMT_RGB888_1X24;
1121 		break;
1122 	}
1123 
1124 	*num_input_fmts = MAX_INPUT_SEL_FORMATS;
1125 
1126 	return input_fmts;
1127 }
1128 
1129 static bool tc358768_mode_fixup(struct drm_bridge *bridge,
1130 				const struct drm_display_mode *mode,
1131 				struct drm_display_mode *adjusted_mode)
1132 {
1133 	/* Default to positive sync */
1134 
1135 	if (!(adjusted_mode->flags &
1136 	      (DRM_MODE_FLAG_PHSYNC | DRM_MODE_FLAG_NHSYNC)))
1137 		adjusted_mode->flags |= DRM_MODE_FLAG_PHSYNC;
1138 
1139 	if (!(adjusted_mode->flags &
1140 	      (DRM_MODE_FLAG_PVSYNC | DRM_MODE_FLAG_NVSYNC)))
1141 		adjusted_mode->flags |= DRM_MODE_FLAG_PVSYNC;
1142 
1143 	return true;
1144 }
1145 
1146 static const struct drm_bridge_funcs tc358768_bridge_funcs = {
1147 	.attach = tc358768_bridge_attach,
1148 	.mode_valid = tc358768_bridge_mode_valid,
1149 	.mode_fixup = tc358768_mode_fixup,
1150 	.pre_enable = tc358768_bridge_pre_enable,
1151 	.enable = tc358768_bridge_enable,
1152 	.disable = tc358768_bridge_disable,
1153 	.post_disable = tc358768_bridge_post_disable,
1154 
1155 	.atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
1156 	.atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
1157 	.atomic_reset = drm_atomic_helper_bridge_reset,
1158 	.atomic_get_input_bus_fmts = tc358768_atomic_get_input_bus_fmts,
1159 };
1160 
1161 static const struct drm_bridge_timings default_tc358768_timings = {
1162 	.input_bus_flags = DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE
1163 		 | DRM_BUS_FLAG_SYNC_SAMPLE_NEGEDGE
1164 		 | DRM_BUS_FLAG_DE_HIGH,
1165 };
1166 
1167 static bool tc358768_is_reserved_reg(unsigned int reg)
1168 {
1169 	switch (reg) {
1170 	case 0x114 ... 0x13f:
1171 	case 0x200:
1172 	case 0x20c:
1173 	case 0x400 ... 0x408:
1174 	case 0x41c ... 0x42f:
1175 		return true;
1176 	default:
1177 		return false;
1178 	}
1179 }
1180 
1181 static bool tc358768_writeable_reg(struct device *dev, unsigned int reg)
1182 {
1183 	if (tc358768_is_reserved_reg(reg))
1184 		return false;
1185 
1186 	switch (reg) {
1187 	case TC358768_CHIPID:
1188 	case TC358768_FIFOSTATUS:
1189 	case TC358768_DSITXSTATUS ... (TC358768_DSITXSTATUS + 2):
1190 	case TC358768_DSI_CONTROL ... (TC358768_DSI_INT_ENA + 2):
1191 	case TC358768_DSICMD_RDFIFO ... (TC358768_DSI_ERR_HALT + 2):
1192 		return false;
1193 	default:
1194 		return true;
1195 	}
1196 }
1197 
1198 static bool tc358768_readable_reg(struct device *dev, unsigned int reg)
1199 {
1200 	if (tc358768_is_reserved_reg(reg))
1201 		return false;
1202 
1203 	switch (reg) {
1204 	case TC358768_STARTCNTRL:
1205 	case TC358768_DSI_CONFW ... (TC358768_DSI_CONFW + 2):
1206 	case TC358768_DSI_INT_CLR ... (TC358768_DSI_INT_CLR + 2):
1207 	case TC358768_DSI_START ... (TC358768_DSI_START + 2):
1208 	case TC358768_DBG_DATA:
1209 		return false;
1210 	default:
1211 		return true;
1212 	}
1213 }
1214 
1215 static const struct regmap_config tc358768_regmap_config = {
1216 	.name = "tc358768",
1217 	.reg_bits = 16,
1218 	.val_bits = 16,
1219 	.max_register = TC358768_DSI_HACT,
1220 	.cache_type = REGCACHE_NONE,
1221 	.writeable_reg = tc358768_writeable_reg,
1222 	.readable_reg = tc358768_readable_reg,
1223 	.reg_format_endian = REGMAP_ENDIAN_BIG,
1224 	.val_format_endian = REGMAP_ENDIAN_BIG,
1225 };
1226 
1227 static const struct i2c_device_id tc358768_i2c_ids[] = {
1228 	{ "tc358768", 0 },
1229 	{ "tc358778", 0 },
1230 	{ }
1231 };
1232 MODULE_DEVICE_TABLE(i2c, tc358768_i2c_ids);
1233 
1234 static const struct of_device_id tc358768_of_ids[] = {
1235 	{ .compatible = "toshiba,tc358768", },
1236 	{ .compatible = "toshiba,tc358778", },
1237 	{ }
1238 };
1239 MODULE_DEVICE_TABLE(of, tc358768_of_ids);
1240 
1241 static int tc358768_get_regulators(struct tc358768_priv *priv)
1242 {
1243 	int i, ret;
1244 
1245 	for (i = 0; i < ARRAY_SIZE(priv->supplies); ++i)
1246 		priv->supplies[i].supply = tc358768_supplies[i];
1247 
1248 	ret = devm_regulator_bulk_get(priv->dev, ARRAY_SIZE(priv->supplies),
1249 				      priv->supplies);
1250 	if (ret < 0)
1251 		dev_err(priv->dev, "failed to get regulators: %d\n", ret);
1252 
1253 	return ret;
1254 }
1255 
1256 static int tc358768_i2c_probe(struct i2c_client *client)
1257 {
1258 	struct tc358768_priv *priv;
1259 	struct device *dev = &client->dev;
1260 	struct device_node *np = dev->of_node;
1261 	int ret;
1262 
1263 	if (!np)
1264 		return -ENODEV;
1265 
1266 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
1267 	if (!priv)
1268 		return -ENOMEM;
1269 
1270 	dev_set_drvdata(dev, priv);
1271 	priv->dev = dev;
1272 
1273 	ret = tc358768_get_regulators(priv);
1274 	if (ret)
1275 		return ret;
1276 
1277 	priv->refclk = devm_clk_get(dev, "refclk");
1278 	if (IS_ERR(priv->refclk))
1279 		return PTR_ERR(priv->refclk);
1280 
1281 	/*
1282 	 * RESX is low active, to disable tc358768 initially (keep in reset)
1283 	 * the gpio line must be LOW. This is the ASSERTED state of
1284 	 * GPIO_ACTIVE_LOW (GPIOD_OUT_HIGH == ASSERTED).
1285 	 */
1286 	priv->reset_gpio  = devm_gpiod_get_optional(dev, "reset",
1287 						    GPIOD_OUT_HIGH);
1288 	if (IS_ERR(priv->reset_gpio))
1289 		return PTR_ERR(priv->reset_gpio);
1290 
1291 	priv->regmap = devm_regmap_init_i2c(client, &tc358768_regmap_config);
1292 	if (IS_ERR(priv->regmap)) {
1293 		dev_err(dev, "Failed to init regmap\n");
1294 		return PTR_ERR(priv->regmap);
1295 	}
1296 
1297 	priv->dsi_host.dev = dev;
1298 	priv->dsi_host.ops = &tc358768_dsi_host_ops;
1299 
1300 	priv->bridge.funcs = &tc358768_bridge_funcs;
1301 	priv->bridge.timings = &default_tc358768_timings;
1302 	priv->bridge.of_node = np;
1303 
1304 	i2c_set_clientdata(client, priv);
1305 
1306 	return mipi_dsi_host_register(&priv->dsi_host);
1307 }
1308 
1309 static void tc358768_i2c_remove(struct i2c_client *client)
1310 {
1311 	struct tc358768_priv *priv = i2c_get_clientdata(client);
1312 
1313 	mipi_dsi_host_unregister(&priv->dsi_host);
1314 }
1315 
1316 static struct i2c_driver tc358768_driver = {
1317 	.driver = {
1318 		.name = "tc358768",
1319 		.of_match_table = tc358768_of_ids,
1320 	},
1321 	.id_table = tc358768_i2c_ids,
1322 	.probe = tc358768_i2c_probe,
1323 	.remove	= tc358768_i2c_remove,
1324 };
1325 module_i2c_driver(tc358768_driver);
1326 
1327 MODULE_AUTHOR("Peter Ujfalusi <peter.ujfalusi@ti.com>");
1328 MODULE_DESCRIPTION("TC358768AXBG/TC358778XBG DSI bridge");
1329 MODULE_LICENSE("GPL v2");
1330