xref: /openbmc/linux/drivers/gpu/drm/bridge/tc358768.c (revision e0d07278)
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/module.h>
13 #include <linux/regmap.h>
14 #include <linux/regulator/consumer.h>
15 #include <linux/slab.h>
16 
17 #include <drm/drm_atomic_helper.h>
18 #include <drm/drm_crtc_helper.h>
19 #include <drm/drm_drv.h>
20 #include <drm/drm_mipi_dsi.h>
21 #include <drm/drm_of.h>
22 #include <drm/drm_panel.h>
23 #include <video/mipi_display.h>
24 #include <video/videomode.h>
25 
26 /* Global (16-bit addressable) */
27 #define TC358768_CHIPID			0x0000
28 #define TC358768_SYSCTL			0x0002
29 #define TC358768_CONFCTL		0x0004
30 #define TC358768_VSDLY			0x0006
31 #define TC358768_DATAFMT		0x0008
32 #define TC358768_GPIOEN			0x000E
33 #define TC358768_GPIODIR		0x0010
34 #define TC358768_GPIOIN			0x0012
35 #define TC358768_GPIOOUT		0x0014
36 #define TC358768_PLLCTL0		0x0016
37 #define TC358768_PLLCTL1		0x0018
38 #define TC358768_CMDBYTE		0x0022
39 #define TC358768_PP_MISC		0x0032
40 #define TC358768_DSITX_DT		0x0050
41 #define TC358768_FIFOSTATUS		0x00F8
42 
43 /* Debug (16-bit addressable) */
44 #define TC358768_VBUFCTRL		0x00E0
45 #define TC358768_DBG_WIDTH		0x00E2
46 #define TC358768_DBG_VBLANK		0x00E4
47 #define TC358768_DBG_DATA		0x00E8
48 
49 /* TX PHY (32-bit addressable) */
50 #define TC358768_CLW_DPHYCONTTX		0x0100
51 #define TC358768_D0W_DPHYCONTTX		0x0104
52 #define TC358768_D1W_DPHYCONTTX		0x0108
53 #define TC358768_D2W_DPHYCONTTX		0x010C
54 #define TC358768_D3W_DPHYCONTTX		0x0110
55 #define TC358768_CLW_CNTRL		0x0140
56 #define TC358768_D0W_CNTRL		0x0144
57 #define TC358768_D1W_CNTRL		0x0148
58 #define TC358768_D2W_CNTRL		0x014C
59 #define TC358768_D3W_CNTRL		0x0150
60 
61 /* TX PPI (32-bit addressable) */
62 #define TC358768_STARTCNTRL		0x0204
63 #define TC358768_DSITXSTATUS		0x0208
64 #define TC358768_LINEINITCNT		0x0210
65 #define TC358768_LPTXTIMECNT		0x0214
66 #define TC358768_TCLK_HEADERCNT		0x0218
67 #define TC358768_TCLK_TRAILCNT		0x021C
68 #define TC358768_THS_HEADERCNT		0x0220
69 #define TC358768_TWAKEUP		0x0224
70 #define TC358768_TCLK_POSTCNT		0x0228
71 #define TC358768_THS_TRAILCNT		0x022C
72 #define TC358768_HSTXVREGCNT		0x0230
73 #define TC358768_HSTXVREGEN		0x0234
74 #define TC358768_TXOPTIONCNTRL		0x0238
75 #define TC358768_BTACNTRL1		0x023C
76 
77 /* TX CTRL (32-bit addressable) */
78 #define TC358768_DSI_CONTROL		0x040C
79 #define TC358768_DSI_STATUS		0x0410
80 #define TC358768_DSI_INT		0x0414
81 #define TC358768_DSI_INT_ENA		0x0418
82 #define TC358768_DSICMD_RDFIFO		0x0430
83 #define TC358768_DSI_ACKERR		0x0434
84 #define TC358768_DSI_ACKERR_INTENA	0x0438
85 #define TC358768_DSI_ACKERR_HALT	0x043c
86 #define TC358768_DSI_RXERR		0x0440
87 #define TC358768_DSI_RXERR_INTENA	0x0444
88 #define TC358768_DSI_RXERR_HALT		0x0448
89 #define TC358768_DSI_ERR		0x044C
90 #define TC358768_DSI_ERR_INTENA		0x0450
91 #define TC358768_DSI_ERR_HALT		0x0454
92 #define TC358768_DSI_CONFW		0x0500
93 #define TC358768_DSI_LPCMD		0x0500
94 #define TC358768_DSI_RESET		0x0504
95 #define TC358768_DSI_INT_CLR		0x050C
96 #define TC358768_DSI_START		0x0518
97 
98 /* DSITX CTRL (16-bit addressable) */
99 #define TC358768_DSICMD_TX		0x0600
100 #define TC358768_DSICMD_TYPE		0x0602
101 #define TC358768_DSICMD_WC		0x0604
102 #define TC358768_DSICMD_WD0		0x0610
103 #define TC358768_DSICMD_WD1		0x0612
104 #define TC358768_DSICMD_WD2		0x0614
105 #define TC358768_DSICMD_WD3		0x0616
106 #define TC358768_DSI_EVENT		0x0620
107 #define TC358768_DSI_VSW		0x0622
108 #define TC358768_DSI_VBPR		0x0624
109 #define TC358768_DSI_VACT		0x0626
110 #define TC358768_DSI_HSW		0x0628
111 #define TC358768_DSI_HBPR		0x062A
112 #define TC358768_DSI_HACT		0x062C
113 
114 /* TC358768_DSI_CONTROL (0x040C) register */
115 #define TC358768_DSI_CONTROL_DIS_MODE	BIT(15)
116 #define TC358768_DSI_CONTROL_TXMD	BIT(7)
117 #define TC358768_DSI_CONTROL_HSCKMD	BIT(5)
118 #define TC358768_DSI_CONTROL_EOTDIS	BIT(0)
119 
120 /* TC358768_DSI_CONFW (0x0500) register */
121 #define TC358768_DSI_CONFW_MODE_SET	(5 << 29)
122 #define TC358768_DSI_CONFW_MODE_CLR	(6 << 29)
123 #define TC358768_DSI_CONFW_ADDR_DSI_CONTROL	(0x3 << 24)
124 
125 static const char * const tc358768_supplies[] = {
126 	"vddc", "vddmipi", "vddio"
127 };
128 
129 struct tc358768_dsi_output {
130 	struct mipi_dsi_device *dev;
131 	struct drm_panel *panel;
132 	struct drm_bridge *bridge;
133 };
134 
135 struct tc358768_priv {
136 	struct device *dev;
137 	struct regmap *regmap;
138 	struct gpio_desc *reset_gpio;
139 	struct regulator_bulk_data supplies[ARRAY_SIZE(tc358768_supplies)];
140 	struct clk *refclk;
141 	int enabled;
142 	int error;
143 
144 	struct mipi_dsi_host dsi_host;
145 	struct drm_bridge bridge;
146 	struct tc358768_dsi_output output;
147 
148 	u32 pd_lines; /* number of Parallel Port Input Data Lines */
149 	u32 dsi_lanes; /* number of DSI Lanes */
150 
151 	/* Parameters for PLL programming */
152 	u32 fbd;	/* PLL feedback divider */
153 	u32 prd;	/* PLL input divider */
154 	u32 frs;	/* PLL Freqency range for HSCK (post divider) */
155 
156 	u32 dsiclk;	/* pll_clk / 2 */
157 };
158 
159 static inline struct tc358768_priv *dsi_host_to_tc358768(struct mipi_dsi_host
160 							 *host)
161 {
162 	return container_of(host, struct tc358768_priv, dsi_host);
163 }
164 
165 static inline struct tc358768_priv *bridge_to_tc358768(struct drm_bridge
166 						       *bridge)
167 {
168 	return container_of(bridge, struct tc358768_priv, bridge);
169 }
170 
171 static int tc358768_clear_error(struct tc358768_priv *priv)
172 {
173 	int ret = priv->error;
174 
175 	priv->error = 0;
176 	return ret;
177 }
178 
179 static void tc358768_write(struct tc358768_priv *priv, u32 reg, u32 val)
180 {
181 	/* work around https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81715 */
182 	int tmpval = val;
183 	size_t count = 2;
184 
185 	if (priv->error)
186 		return;
187 
188 	/* 16-bit register? */
189 	if (reg < 0x100 || reg >= 0x600)
190 		count = 1;
191 
192 	priv->error = regmap_bulk_write(priv->regmap, reg, &tmpval, count);
193 }
194 
195 static void tc358768_read(struct tc358768_priv *priv, u32 reg, u32 *val)
196 {
197 	size_t count = 2;
198 
199 	if (priv->error)
200 		return;
201 
202 	/* 16-bit register? */
203 	if (reg < 0x100 || reg >= 0x600) {
204 		*val = 0;
205 		count = 1;
206 	}
207 
208 	priv->error = regmap_bulk_read(priv->regmap, reg, val, count);
209 }
210 
211 static void tc358768_update_bits(struct tc358768_priv *priv, u32 reg, u32 mask,
212 				 u32 val)
213 {
214 	u32 tmp, orig;
215 
216 	tc358768_read(priv, reg, &orig);
217 	tmp = orig & ~mask;
218 	tmp |= val & mask;
219 	if (tmp != orig)
220 		tc358768_write(priv, reg, tmp);
221 }
222 
223 static int tc358768_sw_reset(struct tc358768_priv *priv)
224 {
225 	/* Assert Reset */
226 	tc358768_write(priv, TC358768_SYSCTL, 1);
227 	/* Release Reset, Exit Sleep */
228 	tc358768_write(priv, TC358768_SYSCTL, 0);
229 
230 	return tc358768_clear_error(priv);
231 }
232 
233 static void tc358768_hw_enable(struct tc358768_priv *priv)
234 {
235 	int ret;
236 
237 	if (priv->enabled)
238 		return;
239 
240 	ret = regulator_bulk_enable(ARRAY_SIZE(priv->supplies), priv->supplies);
241 	if (ret < 0)
242 		dev_err(priv->dev, "error enabling regulators (%d)\n", ret);
243 
244 	if (priv->reset_gpio)
245 		usleep_range(200, 300);
246 
247 	/*
248 	 * The RESX is active low (GPIO_ACTIVE_LOW).
249 	 * DEASSERT (value = 0) the reset_gpio to enable the chip
250 	 */
251 	gpiod_set_value_cansleep(priv->reset_gpio, 0);
252 
253 	/* wait for encoder clocks to stabilize */
254 	usleep_range(1000, 2000);
255 
256 	priv->enabled = true;
257 }
258 
259 static void tc358768_hw_disable(struct tc358768_priv *priv)
260 {
261 	int ret;
262 
263 	if (!priv->enabled)
264 		return;
265 
266 	/*
267 	 * The RESX is active low (GPIO_ACTIVE_LOW).
268 	 * ASSERT (value = 1) the reset_gpio to disable the chip
269 	 */
270 	gpiod_set_value_cansleep(priv->reset_gpio, 1);
271 
272 	ret = regulator_bulk_disable(ARRAY_SIZE(priv->supplies),
273 				     priv->supplies);
274 	if (ret < 0)
275 		dev_err(priv->dev, "error disabling regulators (%d)\n", ret);
276 
277 	priv->enabled = false;
278 }
279 
280 static u32 tc358768_pll_to_pclk(struct tc358768_priv *priv, u32 pll_clk)
281 {
282 	return (u32)div_u64((u64)pll_clk * priv->dsi_lanes, priv->pd_lines);
283 }
284 
285 static u32 tc358768_pclk_to_pll(struct tc358768_priv *priv, u32 pclk)
286 {
287 	return (u32)div_u64((u64)pclk * priv->pd_lines, priv->dsi_lanes);
288 }
289 
290 static int tc358768_calc_pll(struct tc358768_priv *priv,
291 			     const struct drm_display_mode *mode,
292 			     bool verify_only)
293 {
294 	const u32 frs_limits[] = {
295 		1000000000,
296 		500000000,
297 		250000000,
298 		125000000,
299 		62500000
300 	};
301 	unsigned long refclk;
302 	u32 prd, target_pll, i, max_pll, min_pll;
303 	u32 frs, best_diff, best_pll, best_prd, best_fbd;
304 
305 	target_pll = tc358768_pclk_to_pll(priv, mode->clock * 1000);
306 
307 	/* pll_clk = RefClk * [(FBD + 1)/ (PRD + 1)] * [1 / (2^FRS)] */
308 
309 	for (i = 0; i < ARRAY_SIZE(frs_limits); i++)
310 		if (target_pll >= frs_limits[i])
311 			break;
312 
313 	if (i == ARRAY_SIZE(frs_limits) || i == 0)
314 		return -EINVAL;
315 
316 	frs = i - 1;
317 	max_pll = frs_limits[i - 1];
318 	min_pll = frs_limits[i];
319 
320 	refclk = clk_get_rate(priv->refclk);
321 
322 	best_diff = UINT_MAX;
323 	best_pll = 0;
324 	best_prd = 0;
325 	best_fbd = 0;
326 
327 	for (prd = 0; prd < 16; ++prd) {
328 		u32 divisor = (prd + 1) * (1 << frs);
329 		u32 fbd;
330 
331 		for (fbd = 0; fbd < 512; ++fbd) {
332 			u32 pll, diff;
333 
334 			pll = (u32)div_u64((u64)refclk * (fbd + 1), divisor);
335 
336 			if (pll >= max_pll || pll < min_pll)
337 				continue;
338 
339 			diff = max(pll, target_pll) - min(pll, target_pll);
340 
341 			if (diff < best_diff) {
342 				best_diff = diff;
343 				best_pll = pll;
344 				best_prd = prd;
345 				best_fbd = fbd;
346 
347 				if (best_diff == 0)
348 					goto found;
349 			}
350 		}
351 	}
352 
353 	if (best_diff == UINT_MAX) {
354 		dev_err(priv->dev, "could not find suitable PLL setup\n");
355 		return -EINVAL;
356 	}
357 
358 found:
359 	if (verify_only)
360 		return 0;
361 
362 	priv->fbd = best_fbd;
363 	priv->prd = best_prd;
364 	priv->frs = frs;
365 	priv->dsiclk = best_pll / 2;
366 
367 	return 0;
368 }
369 
370 static int tc358768_dsi_host_attach(struct mipi_dsi_host *host,
371 				    struct mipi_dsi_device *dev)
372 {
373 	struct tc358768_priv *priv = dsi_host_to_tc358768(host);
374 	struct drm_bridge *bridge;
375 	struct drm_panel *panel;
376 	struct device_node *ep;
377 	int ret;
378 
379 	if (dev->lanes > 4) {
380 		dev_err(priv->dev, "unsupported number of data lanes(%u)\n",
381 			dev->lanes);
382 		return -EINVAL;
383 	}
384 
385 	/*
386 	 * tc358768 supports both Video and Pulse mode, but the driver only
387 	 * implements Video (event) mode currently
388 	 */
389 	if (!(dev->mode_flags & MIPI_DSI_MODE_VIDEO)) {
390 		dev_err(priv->dev, "Only MIPI_DSI_MODE_VIDEO is supported\n");
391 		return -ENOTSUPP;
392 	}
393 
394 	/*
395 	 * tc358768 supports RGB888, RGB666, RGB666_PACKED and RGB565, but only
396 	 * RGB888 is verified.
397 	 */
398 	if (dev->format != MIPI_DSI_FMT_RGB888) {
399 		dev_warn(priv->dev, "Only MIPI_DSI_FMT_RGB888 tested!\n");
400 		return -ENOTSUPP;
401 	}
402 
403 	ret = drm_of_find_panel_or_bridge(host->dev->of_node, 1, 0, &panel,
404 					  &bridge);
405 	if (ret)
406 		return ret;
407 
408 	if (panel) {
409 		bridge = drm_panel_bridge_add_typed(panel,
410 						    DRM_MODE_CONNECTOR_DSI);
411 		if (IS_ERR(bridge))
412 			return PTR_ERR(bridge);
413 	}
414 
415 	priv->output.dev = dev;
416 	priv->output.bridge = bridge;
417 	priv->output.panel = panel;
418 
419 	priv->dsi_lanes = dev->lanes;
420 
421 	/* get input ep (port0/endpoint0) */
422 	ret = -EINVAL;
423 	ep = of_graph_get_endpoint_by_regs(host->dev->of_node, 0, 0);
424 	if (ep) {
425 		ret = of_property_read_u32(ep, "data-lines", &priv->pd_lines);
426 
427 		of_node_put(ep);
428 	}
429 
430 	if (ret)
431 		priv->pd_lines = mipi_dsi_pixel_format_to_bpp(dev->format);
432 
433 	drm_bridge_add(&priv->bridge);
434 
435 	return 0;
436 }
437 
438 static int tc358768_dsi_host_detach(struct mipi_dsi_host *host,
439 				    struct mipi_dsi_device *dev)
440 {
441 	struct tc358768_priv *priv = dsi_host_to_tc358768(host);
442 
443 	drm_bridge_remove(&priv->bridge);
444 	if (priv->output.panel)
445 		drm_panel_bridge_remove(priv->output.bridge);
446 
447 	return 0;
448 }
449 
450 static ssize_t tc358768_dsi_host_transfer(struct mipi_dsi_host *host,
451 					  const struct mipi_dsi_msg *msg)
452 {
453 	struct tc358768_priv *priv = dsi_host_to_tc358768(host);
454 	struct mipi_dsi_packet packet;
455 	int ret;
456 
457 	if (!priv->enabled) {
458 		dev_err(priv->dev, "Bridge is not enabled\n");
459 		return -ENODEV;
460 	}
461 
462 	if (msg->rx_len) {
463 		dev_warn(priv->dev, "MIPI rx is not supported\n");
464 		return -ENOTSUPP;
465 	}
466 
467 	if (msg->tx_len > 8) {
468 		dev_warn(priv->dev, "Maximum 8 byte MIPI tx is supported\n");
469 		return -ENOTSUPP;
470 	}
471 
472 	ret = mipi_dsi_create_packet(&packet, msg);
473 	if (ret)
474 		return ret;
475 
476 	if (mipi_dsi_packet_format_is_short(msg->type)) {
477 		tc358768_write(priv, TC358768_DSICMD_TYPE,
478 			       (0x10 << 8) | (packet.header[0] & 0x3f));
479 		tc358768_write(priv, TC358768_DSICMD_WC, 0);
480 		tc358768_write(priv, TC358768_DSICMD_WD0,
481 			       (packet.header[2] << 8) | packet.header[1]);
482 	} else {
483 		int i;
484 
485 		tc358768_write(priv, TC358768_DSICMD_TYPE,
486 			       (0x40 << 8) | (packet.header[0] & 0x3f));
487 		tc358768_write(priv, TC358768_DSICMD_WC, packet.payload_length);
488 		for (i = 0; i < packet.payload_length; i += 2) {
489 			u16 val = packet.payload[i];
490 
491 			if (i + 1 < packet.payload_length)
492 				val |= packet.payload[i + 1] << 8;
493 
494 			tc358768_write(priv, TC358768_DSICMD_WD0 + i, val);
495 		}
496 	}
497 
498 	/* start transfer */
499 	tc358768_write(priv, TC358768_DSICMD_TX, 1);
500 
501 	ret = tc358768_clear_error(priv);
502 	if (ret)
503 		dev_warn(priv->dev, "Software disable failed: %d\n", ret);
504 	else
505 		ret = packet.size;
506 
507 	return ret;
508 }
509 
510 static const struct mipi_dsi_host_ops tc358768_dsi_host_ops = {
511 	.attach = tc358768_dsi_host_attach,
512 	.detach = tc358768_dsi_host_detach,
513 	.transfer = tc358768_dsi_host_transfer,
514 };
515 
516 static int tc358768_bridge_attach(struct drm_bridge *bridge,
517 				  enum drm_bridge_attach_flags flags)
518 {
519 	struct tc358768_priv *priv = bridge_to_tc358768(bridge);
520 
521 	if (!drm_core_check_feature(bridge->dev, DRIVER_ATOMIC)) {
522 		dev_err(priv->dev, "needs atomic updates support\n");
523 		return -ENOTSUPP;
524 	}
525 
526 	return drm_bridge_attach(bridge->encoder, priv->output.bridge, bridge,
527 				 flags);
528 }
529 
530 static enum drm_mode_status
531 tc358768_bridge_mode_valid(struct drm_bridge *bridge,
532 			   const struct drm_display_info *info,
533 			   const struct drm_display_mode *mode)
534 {
535 	struct tc358768_priv *priv = bridge_to_tc358768(bridge);
536 
537 	if (tc358768_calc_pll(priv, mode, true))
538 		return MODE_CLOCK_RANGE;
539 
540 	return MODE_OK;
541 }
542 
543 static void tc358768_bridge_disable(struct drm_bridge *bridge)
544 {
545 	struct tc358768_priv *priv = bridge_to_tc358768(bridge);
546 	int ret;
547 
548 	/* set FrmStop */
549 	tc358768_update_bits(priv, TC358768_PP_MISC, BIT(15), BIT(15));
550 
551 	/* wait at least for one frame */
552 	msleep(50);
553 
554 	/* clear PP_en */
555 	tc358768_update_bits(priv, TC358768_CONFCTL, BIT(6), 0);
556 
557 	/* set RstPtr */
558 	tc358768_update_bits(priv, TC358768_PP_MISC, BIT(14), BIT(14));
559 
560 	ret = tc358768_clear_error(priv);
561 	if (ret)
562 		dev_warn(priv->dev, "Software disable failed: %d\n", ret);
563 }
564 
565 static void tc358768_bridge_post_disable(struct drm_bridge *bridge)
566 {
567 	struct tc358768_priv *priv = bridge_to_tc358768(bridge);
568 
569 	tc358768_hw_disable(priv);
570 }
571 
572 static int tc358768_setup_pll(struct tc358768_priv *priv,
573 			      const struct drm_display_mode *mode)
574 {
575 	u32 fbd, prd, frs;
576 	int ret;
577 
578 	ret = tc358768_calc_pll(priv, mode, false);
579 	if (ret) {
580 		dev_err(priv->dev, "PLL calculation failed: %d\n", ret);
581 		return ret;
582 	}
583 
584 	fbd = priv->fbd;
585 	prd = priv->prd;
586 	frs = priv->frs;
587 
588 	dev_dbg(priv->dev, "PLL: refclk %lu, fbd %u, prd %u, frs %u\n",
589 		clk_get_rate(priv->refclk), fbd, prd, frs);
590 	dev_dbg(priv->dev, "PLL: pll_clk: %u, DSIClk %u, DSIByteClk %u\n",
591 		priv->dsiclk * 2, priv->dsiclk, priv->dsiclk / 4);
592 	dev_dbg(priv->dev, "PLL: pclk %u (panel: %u)\n",
593 		tc358768_pll_to_pclk(priv, priv->dsiclk * 2),
594 		mode->clock * 1000);
595 
596 	/* PRD[15:12] FBD[8:0] */
597 	tc358768_write(priv, TC358768_PLLCTL0, (prd << 12) | fbd);
598 
599 	/* FRS[11:10] LBWS[9:8] CKEN[4] RESETB[1] EN[0] */
600 	tc358768_write(priv, TC358768_PLLCTL1,
601 		       (frs << 10) | (0x2 << 8) | BIT(1) | BIT(0));
602 
603 	/* wait for lock */
604 	usleep_range(1000, 2000);
605 
606 	/* FRS[11:10] LBWS[9:8] CKEN[4] PLL_CKEN[4] RESETB[1] EN[0] */
607 	tc358768_write(priv, TC358768_PLLCTL1,
608 		       (frs << 10) | (0x2 << 8) | BIT(4) | BIT(1) | BIT(0));
609 
610 	return tc358768_clear_error(priv);
611 }
612 
613 #define TC358768_PRECISION	1000
614 static u32 tc358768_ns_to_cnt(u32 ns, u32 period_nsk)
615 {
616 	return (ns * TC358768_PRECISION + period_nsk) / period_nsk;
617 }
618 
619 static u32 tc358768_to_ns(u32 nsk)
620 {
621 	return (nsk / TC358768_PRECISION);
622 }
623 
624 static void tc358768_bridge_pre_enable(struct drm_bridge *bridge)
625 {
626 	struct tc358768_priv *priv = bridge_to_tc358768(bridge);
627 	struct mipi_dsi_device *dsi_dev = priv->output.dev;
628 	u32 val, val2, lptxcnt, hact, data_type;
629 	const struct drm_display_mode *mode;
630 	u32 dsibclk_nsk, dsiclk_nsk, ui_nsk, phy_delay_nsk;
631 	u32 dsiclk, dsibclk;
632 	int ret, i;
633 
634 	tc358768_hw_enable(priv);
635 
636 	ret = tc358768_sw_reset(priv);
637 	if (ret) {
638 		dev_err(priv->dev, "Software reset failed: %d\n", ret);
639 		tc358768_hw_disable(priv);
640 		return;
641 	}
642 
643 	mode = &bridge->encoder->crtc->state->adjusted_mode;
644 	ret = tc358768_setup_pll(priv, mode);
645 	if (ret) {
646 		dev_err(priv->dev, "PLL setup failed: %d\n", ret);
647 		tc358768_hw_disable(priv);
648 		return;
649 	}
650 
651 	dsiclk = priv->dsiclk;
652 	dsibclk = dsiclk / 4;
653 
654 	/* Data Format Control Register */
655 	val = BIT(2) | BIT(1) | BIT(0); /* rdswap_en | dsitx_en | txdt_en */
656 	switch (dsi_dev->format) {
657 	case MIPI_DSI_FMT_RGB888:
658 		val |= (0x3 << 4);
659 		hact = mode->hdisplay * 3;
660 		data_type = MIPI_DSI_PACKED_PIXEL_STREAM_24;
661 		break;
662 	case MIPI_DSI_FMT_RGB666:
663 		val |= (0x4 << 4);
664 		hact = mode->hdisplay * 3;
665 		data_type = MIPI_DSI_PACKED_PIXEL_STREAM_18;
666 		break;
667 
668 	case MIPI_DSI_FMT_RGB666_PACKED:
669 		val |= (0x4 << 4) | BIT(3);
670 		hact = mode->hdisplay * 18 / 8;
671 		data_type = MIPI_DSI_PIXEL_STREAM_3BYTE_18;
672 		break;
673 
674 	case MIPI_DSI_FMT_RGB565:
675 		val |= (0x5 << 4);
676 		hact = mode->hdisplay * 2;
677 		data_type = MIPI_DSI_PACKED_PIXEL_STREAM_16;
678 		break;
679 	default:
680 		dev_err(priv->dev, "Invalid data format (%u)\n",
681 			dsi_dev->format);
682 		tc358768_hw_disable(priv);
683 		return;
684 	}
685 
686 	/* VSDly[9:0] */
687 	tc358768_write(priv, TC358768_VSDLY, 1);
688 
689 	tc358768_write(priv, TC358768_DATAFMT, val);
690 	tc358768_write(priv, TC358768_DSITX_DT, data_type);
691 
692 	/* Enable D-PHY (HiZ->LP11) */
693 	tc358768_write(priv, TC358768_CLW_CNTRL, 0x0000);
694 	/* Enable lanes */
695 	for (i = 0; i < dsi_dev->lanes; i++)
696 		tc358768_write(priv, TC358768_D0W_CNTRL + i * 4, 0x0000);
697 
698 	/* DSI Timings */
699 	dsibclk_nsk = (u32)div_u64((u64)1000000000 * TC358768_PRECISION,
700 				  dsibclk);
701 	dsiclk_nsk = (u32)div_u64((u64)1000000000 * TC358768_PRECISION, dsiclk);
702 	ui_nsk = dsiclk_nsk / 2;
703 	phy_delay_nsk = dsibclk_nsk + 2 * dsiclk_nsk;
704 	dev_dbg(priv->dev, "dsiclk_nsk: %u\n", dsiclk_nsk);
705 	dev_dbg(priv->dev, "ui_nsk: %u\n", ui_nsk);
706 	dev_dbg(priv->dev, "dsibclk_nsk: %u\n", dsibclk_nsk);
707 	dev_dbg(priv->dev, "phy_delay_nsk: %u\n", phy_delay_nsk);
708 
709 	/* LP11 > 100us for D-PHY Rx Init */
710 	val = tc358768_ns_to_cnt(100 * 1000, dsibclk_nsk) - 1;
711 	dev_dbg(priv->dev, "LINEINITCNT: 0x%x\n", val);
712 	tc358768_write(priv, TC358768_LINEINITCNT, val);
713 
714 	/* LPTimeCnt > 50ns */
715 	val = tc358768_ns_to_cnt(50, dsibclk_nsk) - 1;
716 	lptxcnt = val;
717 	dev_dbg(priv->dev, "LPTXTIMECNT: 0x%x\n", val);
718 	tc358768_write(priv, TC358768_LPTXTIMECNT, val);
719 
720 	/* 38ns < TCLK_PREPARE < 95ns */
721 	val = tc358768_ns_to_cnt(65, dsibclk_nsk) - 1;
722 	/* TCLK_PREPARE > 300ns */
723 	val2 = tc358768_ns_to_cnt(300 + tc358768_to_ns(3 * ui_nsk),
724 				  dsibclk_nsk);
725 	val |= (val2 - tc358768_to_ns(phy_delay_nsk - dsibclk_nsk)) << 8;
726 	dev_dbg(priv->dev, "TCLK_HEADERCNT: 0x%x\n", val);
727 	tc358768_write(priv, TC358768_TCLK_HEADERCNT, val);
728 
729 	/* TCLK_TRAIL > 60ns + 3*UI */
730 	val = 60 + tc358768_to_ns(3 * ui_nsk);
731 	val = tc358768_ns_to_cnt(val, dsibclk_nsk) - 5;
732 	dev_dbg(priv->dev, "TCLK_TRAILCNT: 0x%x\n", val);
733 	tc358768_write(priv, TC358768_TCLK_TRAILCNT, val);
734 
735 	/* 40ns + 4*UI < THS_PREPARE < 85ns + 6*UI */
736 	val = 50 + tc358768_to_ns(4 * ui_nsk);
737 	val = tc358768_ns_to_cnt(val, dsibclk_nsk) - 1;
738 	/* THS_ZERO > 145ns + 10*UI */
739 	val2 = tc358768_ns_to_cnt(145 - tc358768_to_ns(ui_nsk), dsibclk_nsk);
740 	val |= (val2 - tc358768_to_ns(phy_delay_nsk)) << 8;
741 	dev_dbg(priv->dev, "THS_HEADERCNT: 0x%x\n", val);
742 	tc358768_write(priv, TC358768_THS_HEADERCNT, val);
743 
744 	/* TWAKEUP > 1ms in lptxcnt steps */
745 	val = tc358768_ns_to_cnt(1020000, dsibclk_nsk);
746 	val = val / (lptxcnt + 1) - 1;
747 	dev_dbg(priv->dev, "TWAKEUP: 0x%x\n", val);
748 	tc358768_write(priv, TC358768_TWAKEUP, val);
749 
750 	/* TCLK_POSTCNT > 60ns + 52*UI */
751 	val = tc358768_ns_to_cnt(60 + tc358768_to_ns(52 * ui_nsk),
752 				 dsibclk_nsk) - 3;
753 	dev_dbg(priv->dev, "TCLK_POSTCNT: 0x%x\n", val);
754 	tc358768_write(priv, TC358768_TCLK_POSTCNT, val);
755 
756 	/* 60ns + 4*UI < THS_PREPARE < 105ns + 12*UI */
757 	val = tc358768_ns_to_cnt(60 + tc358768_to_ns(15 * ui_nsk),
758 				 dsibclk_nsk) - 5;
759 	dev_dbg(priv->dev, "THS_TRAILCNT: 0x%x\n", val);
760 	tc358768_write(priv, TC358768_THS_TRAILCNT, val);
761 
762 	val = BIT(0);
763 	for (i = 0; i < dsi_dev->lanes; i++)
764 		val |= BIT(i + 1);
765 	tc358768_write(priv, TC358768_HSTXVREGEN, val);
766 
767 	if (!(dsi_dev->mode_flags & MIPI_DSI_CLOCK_NON_CONTINUOUS))
768 		tc358768_write(priv, TC358768_TXOPTIONCNTRL, 0x1);
769 
770 	/* TXTAGOCNT[26:16] RXTASURECNT[10:0] */
771 	val = tc358768_to_ns((lptxcnt + 1) * dsibclk_nsk * 4);
772 	val = tc358768_ns_to_cnt(val, dsibclk_nsk) - 1;
773 	val2 = tc358768_ns_to_cnt(tc358768_to_ns((lptxcnt + 1) * dsibclk_nsk),
774 				  dsibclk_nsk) - 2;
775 	val |= val2 << 16;
776 	dev_dbg(priv->dev, "BTACNTRL1: 0x%x\n", val);
777 	tc358768_write(priv, TC358768_BTACNTRL1, val);
778 
779 	/* START[0] */
780 	tc358768_write(priv, TC358768_STARTCNTRL, 1);
781 
782 	/* Set event mode */
783 	tc358768_write(priv, TC358768_DSI_EVENT, 1);
784 
785 	/* vsw (+ vbp) */
786 	tc358768_write(priv, TC358768_DSI_VSW,
787 		       mode->vtotal - mode->vsync_start);
788 	/* vbp (not used in event mode) */
789 	tc358768_write(priv, TC358768_DSI_VBPR, 0);
790 	/* vact */
791 	tc358768_write(priv, TC358768_DSI_VACT, mode->vdisplay);
792 
793 	/* (hsw + hbp) * byteclk * ndl / pclk */
794 	val = (u32)div_u64((mode->htotal - mode->hsync_start) *
795 			   ((u64)priv->dsiclk / 4) * priv->dsi_lanes,
796 			   mode->clock * 1000);
797 	tc358768_write(priv, TC358768_DSI_HSW, val);
798 	/* hbp (not used in event mode) */
799 	tc358768_write(priv, TC358768_DSI_HBPR, 0);
800 	/* hact (bytes) */
801 	tc358768_write(priv, TC358768_DSI_HACT, hact);
802 
803 	/* VSYNC polarity */
804 	if (!(mode->flags & DRM_MODE_FLAG_NVSYNC))
805 		tc358768_update_bits(priv, TC358768_CONFCTL, BIT(5), BIT(5));
806 	/* HSYNC polarity */
807 	if (mode->flags & DRM_MODE_FLAG_PHSYNC)
808 		tc358768_update_bits(priv, TC358768_PP_MISC, BIT(0), BIT(0));
809 
810 	/* Start DSI Tx */
811 	tc358768_write(priv, TC358768_DSI_START, 0x1);
812 
813 	/* Configure DSI_Control register */
814 	val = TC358768_DSI_CONFW_MODE_CLR | TC358768_DSI_CONFW_ADDR_DSI_CONTROL;
815 	val |= TC358768_DSI_CONTROL_TXMD | TC358768_DSI_CONTROL_HSCKMD |
816 	       0x3 << 1 | TC358768_DSI_CONTROL_EOTDIS;
817 	tc358768_write(priv, TC358768_DSI_CONFW, val);
818 
819 	val = TC358768_DSI_CONFW_MODE_SET | TC358768_DSI_CONFW_ADDR_DSI_CONTROL;
820 	val |= (dsi_dev->lanes - 1) << 1;
821 
822 	if (!(dsi_dev->mode_flags & MIPI_DSI_MODE_LPM))
823 		val |= TC358768_DSI_CONTROL_TXMD;
824 
825 	if (!(dsi_dev->mode_flags & MIPI_DSI_CLOCK_NON_CONTINUOUS))
826 		val |= TC358768_DSI_CONTROL_HSCKMD;
827 
828 	if (dsi_dev->mode_flags & MIPI_DSI_MODE_EOT_PACKET)
829 		val |= TC358768_DSI_CONTROL_EOTDIS;
830 
831 	tc358768_write(priv, TC358768_DSI_CONFW, val);
832 
833 	val = TC358768_DSI_CONFW_MODE_CLR | TC358768_DSI_CONFW_ADDR_DSI_CONTROL;
834 	val |= TC358768_DSI_CONTROL_DIS_MODE; /* DSI mode */
835 	tc358768_write(priv, TC358768_DSI_CONFW, val);
836 
837 	ret = tc358768_clear_error(priv);
838 	if (ret) {
839 		dev_err(priv->dev, "Bridge pre_enable failed: %d\n", ret);
840 		tc358768_bridge_disable(bridge);
841 		tc358768_bridge_post_disable(bridge);
842 	}
843 }
844 
845 static void tc358768_bridge_enable(struct drm_bridge *bridge)
846 {
847 	struct tc358768_priv *priv = bridge_to_tc358768(bridge);
848 	int ret;
849 
850 	if (!priv->enabled) {
851 		dev_err(priv->dev, "Bridge is not enabled\n");
852 		return;
853 	}
854 
855 	/* clear FrmStop and RstPtr */
856 	tc358768_update_bits(priv, TC358768_PP_MISC, 0x3 << 14, 0);
857 
858 	/* set PP_en */
859 	tc358768_update_bits(priv, TC358768_CONFCTL, BIT(6), BIT(6));
860 
861 	ret = tc358768_clear_error(priv);
862 	if (ret) {
863 		dev_err(priv->dev, "Bridge enable failed: %d\n", ret);
864 		tc358768_bridge_disable(bridge);
865 		tc358768_bridge_post_disable(bridge);
866 	}
867 }
868 
869 static const struct drm_bridge_funcs tc358768_bridge_funcs = {
870 	.attach = tc358768_bridge_attach,
871 	.mode_valid = tc358768_bridge_mode_valid,
872 	.pre_enable = tc358768_bridge_pre_enable,
873 	.enable = tc358768_bridge_enable,
874 	.disable = tc358768_bridge_disable,
875 	.post_disable = tc358768_bridge_post_disable,
876 };
877 
878 static const struct drm_bridge_timings default_tc358768_timings = {
879 	.input_bus_flags = DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE
880 		 | DRM_BUS_FLAG_SYNC_SAMPLE_NEGEDGE
881 		 | DRM_BUS_FLAG_DE_HIGH,
882 };
883 
884 static bool tc358768_is_reserved_reg(unsigned int reg)
885 {
886 	switch (reg) {
887 	case 0x114 ... 0x13f:
888 	case 0x200:
889 	case 0x20c:
890 	case 0x400 ... 0x408:
891 	case 0x41c ... 0x42f:
892 		return true;
893 	default:
894 		return false;
895 	}
896 }
897 
898 static bool tc358768_writeable_reg(struct device *dev, unsigned int reg)
899 {
900 	if (tc358768_is_reserved_reg(reg))
901 		return false;
902 
903 	switch (reg) {
904 	case TC358768_CHIPID:
905 	case TC358768_FIFOSTATUS:
906 	case TC358768_DSITXSTATUS ... (TC358768_DSITXSTATUS + 2):
907 	case TC358768_DSI_CONTROL ... (TC358768_DSI_INT_ENA + 2):
908 	case TC358768_DSICMD_RDFIFO ... (TC358768_DSI_ERR_HALT + 2):
909 		return false;
910 	default:
911 		return true;
912 	}
913 }
914 
915 static bool tc358768_readable_reg(struct device *dev, unsigned int reg)
916 {
917 	if (tc358768_is_reserved_reg(reg))
918 		return false;
919 
920 	switch (reg) {
921 	case TC358768_STARTCNTRL:
922 	case TC358768_DSI_CONFW ... (TC358768_DSI_CONFW + 2):
923 	case TC358768_DSI_INT_CLR ... (TC358768_DSI_INT_CLR + 2):
924 	case TC358768_DSI_START ... (TC358768_DSI_START + 2):
925 	case TC358768_DBG_DATA:
926 		return false;
927 	default:
928 		return true;
929 	}
930 }
931 
932 static const struct regmap_config tc358768_regmap_config = {
933 	.name = "tc358768",
934 	.reg_bits = 16,
935 	.val_bits = 16,
936 	.max_register = TC358768_DSI_HACT,
937 	.cache_type = REGCACHE_NONE,
938 	.writeable_reg = tc358768_writeable_reg,
939 	.readable_reg = tc358768_readable_reg,
940 	.reg_format_endian = REGMAP_ENDIAN_BIG,
941 	.val_format_endian = REGMAP_ENDIAN_BIG,
942 };
943 
944 static const struct i2c_device_id tc358768_i2c_ids[] = {
945 	{ "tc358768", 0 },
946 	{ "tc358778", 0 },
947 	{ }
948 };
949 MODULE_DEVICE_TABLE(i2c, tc358768_i2c_ids);
950 
951 static const struct of_device_id tc358768_of_ids[] = {
952 	{ .compatible = "toshiba,tc358768", },
953 	{ .compatible = "toshiba,tc358778", },
954 	{ }
955 };
956 MODULE_DEVICE_TABLE(of, tc358768_of_ids);
957 
958 static int tc358768_get_regulators(struct tc358768_priv *priv)
959 {
960 	int i, ret;
961 
962 	for (i = 0; i < ARRAY_SIZE(priv->supplies); ++i)
963 		priv->supplies[i].supply = tc358768_supplies[i];
964 
965 	ret = devm_regulator_bulk_get(priv->dev, ARRAY_SIZE(priv->supplies),
966 				      priv->supplies);
967 	if (ret < 0)
968 		dev_err(priv->dev, "failed to get regulators: %d\n", ret);
969 
970 	return ret;
971 }
972 
973 static int tc358768_i2c_probe(struct i2c_client *client,
974 			      const struct i2c_device_id *id)
975 {
976 	struct tc358768_priv *priv;
977 	struct device *dev = &client->dev;
978 	struct device_node *np = dev->of_node;
979 	int ret;
980 
981 	if (!np)
982 		return -ENODEV;
983 
984 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
985 	if (!priv)
986 		return -ENOMEM;
987 
988 	dev_set_drvdata(dev, priv);
989 	priv->dev = dev;
990 
991 	ret = tc358768_get_regulators(priv);
992 	if (ret)
993 		return ret;
994 
995 	priv->refclk = devm_clk_get(dev, "refclk");
996 	if (IS_ERR(priv->refclk))
997 		return PTR_ERR(priv->refclk);
998 
999 	/*
1000 	 * RESX is low active, to disable tc358768 initially (keep in reset)
1001 	 * the gpio line must be LOW. This is the ASSERTED state of
1002 	 * GPIO_ACTIVE_LOW (GPIOD_OUT_HIGH == ASSERTED).
1003 	 */
1004 	priv->reset_gpio  = devm_gpiod_get_optional(dev, "reset",
1005 						    GPIOD_OUT_HIGH);
1006 	if (IS_ERR(priv->reset_gpio))
1007 		return PTR_ERR(priv->reset_gpio);
1008 
1009 	priv->regmap = devm_regmap_init_i2c(client, &tc358768_regmap_config);
1010 	if (IS_ERR(priv->regmap)) {
1011 		dev_err(dev, "Failed to init regmap\n");
1012 		return PTR_ERR(priv->regmap);
1013 	}
1014 
1015 	priv->dsi_host.dev = dev;
1016 	priv->dsi_host.ops = &tc358768_dsi_host_ops;
1017 
1018 	priv->bridge.funcs = &tc358768_bridge_funcs;
1019 	priv->bridge.timings = &default_tc358768_timings;
1020 	priv->bridge.of_node = np;
1021 
1022 	i2c_set_clientdata(client, priv);
1023 
1024 	return mipi_dsi_host_register(&priv->dsi_host);
1025 }
1026 
1027 static int tc358768_i2c_remove(struct i2c_client *client)
1028 {
1029 	struct tc358768_priv *priv = i2c_get_clientdata(client);
1030 
1031 	mipi_dsi_host_unregister(&priv->dsi_host);
1032 
1033 	return 0;
1034 }
1035 
1036 static struct i2c_driver tc358768_driver = {
1037 	.driver = {
1038 		.name = "tc358768",
1039 		.of_match_table = tc358768_of_ids,
1040 	},
1041 	.id_table = tc358768_i2c_ids,
1042 	.probe = tc358768_i2c_probe,
1043 	.remove	= tc358768_i2c_remove,
1044 };
1045 module_i2c_driver(tc358768_driver);
1046 
1047 MODULE_AUTHOR("Peter Ujfalusi <peter.ujfalusi@ti.com>");
1048 MODULE_DESCRIPTION("TC358768AXBG/TC358778XBG DSI bridge");
1049 MODULE_LICENSE("GPL v2");
1050