xref: /openbmc/linux/drivers/gpu/drm/bridge/tc358768.c (revision 1a312ed8)
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 /* TC358768_DSICMD_TX (0x0600) register */
129 #define TC358768_DSI_CMDTX_DC_START	BIT(0)
130 
131 static const char * const tc358768_supplies[] = {
132 	"vddc", "vddmipi", "vddio"
133 };
134 
135 struct tc358768_dsi_output {
136 	struct mipi_dsi_device *dev;
137 	struct drm_panel *panel;
138 	struct drm_bridge *bridge;
139 };
140 
141 struct tc358768_priv {
142 	struct device *dev;
143 	struct regmap *regmap;
144 	struct gpio_desc *reset_gpio;
145 	struct regulator_bulk_data supplies[ARRAY_SIZE(tc358768_supplies)];
146 	struct clk *refclk;
147 	int enabled;
148 	int error;
149 
150 	struct mipi_dsi_host dsi_host;
151 	struct drm_bridge bridge;
152 	struct tc358768_dsi_output output;
153 
154 	u32 pd_lines; /* number of Parallel Port Input Data Lines */
155 	u32 dsi_lanes; /* number of DSI Lanes */
156 	u32 dsi_bpp; /* number of Bits Per Pixel over DSI */
157 
158 	/* Parameters for PLL programming */
159 	u32 fbd;	/* PLL feedback divider */
160 	u32 prd;	/* PLL input divider */
161 	u32 frs;	/* PLL Freqency range for HSCK (post divider) */
162 
163 	u32 dsiclk;	/* pll_clk / 2 */
164 	u32 pclk;	/* incoming pclk rate */
165 };
166 
dsi_host_to_tc358768(struct mipi_dsi_host * host)167 static inline struct tc358768_priv *dsi_host_to_tc358768(struct mipi_dsi_host
168 							 *host)
169 {
170 	return container_of(host, struct tc358768_priv, dsi_host);
171 }
172 
bridge_to_tc358768(struct drm_bridge * bridge)173 static inline struct tc358768_priv *bridge_to_tc358768(struct drm_bridge
174 						       *bridge)
175 {
176 	return container_of(bridge, struct tc358768_priv, bridge);
177 }
178 
tc358768_clear_error(struct tc358768_priv * priv)179 static int tc358768_clear_error(struct tc358768_priv *priv)
180 {
181 	int ret = priv->error;
182 
183 	priv->error = 0;
184 	return ret;
185 }
186 
tc358768_write(struct tc358768_priv * priv,u32 reg,u32 val)187 static void tc358768_write(struct tc358768_priv *priv, u32 reg, u32 val)
188 {
189 	/* work around https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81715 */
190 	int tmpval = val;
191 	size_t count = 2;
192 
193 	if (priv->error)
194 		return;
195 
196 	/* 16-bit register? */
197 	if (reg < 0x100 || reg >= 0x600)
198 		count = 1;
199 
200 	priv->error = regmap_bulk_write(priv->regmap, reg, &tmpval, count);
201 }
202 
tc358768_read(struct tc358768_priv * priv,u32 reg,u32 * val)203 static void tc358768_read(struct tc358768_priv *priv, u32 reg, u32 *val)
204 {
205 	size_t count = 2;
206 
207 	if (priv->error)
208 		return;
209 
210 	/* 16-bit register? */
211 	if (reg < 0x100 || reg >= 0x600) {
212 		*val = 0;
213 		count = 1;
214 	}
215 
216 	priv->error = regmap_bulk_read(priv->regmap, reg, val, count);
217 }
218 
tc358768_update_bits(struct tc358768_priv * priv,u32 reg,u32 mask,u32 val)219 static void tc358768_update_bits(struct tc358768_priv *priv, u32 reg, u32 mask,
220 				 u32 val)
221 {
222 	u32 tmp, orig;
223 
224 	tc358768_read(priv, reg, &orig);
225 
226 	if (priv->error)
227 		return;
228 
229 	tmp = orig & ~mask;
230 	tmp |= val & mask;
231 	if (tmp != orig)
232 		tc358768_write(priv, reg, tmp);
233 }
234 
tc358768_dsicmd_tx(struct tc358768_priv * priv)235 static void tc358768_dsicmd_tx(struct tc358768_priv *priv)
236 {
237 	u32 val;
238 
239 	/* start transfer */
240 	tc358768_write(priv, TC358768_DSICMD_TX, TC358768_DSI_CMDTX_DC_START);
241 	if (priv->error)
242 		return;
243 
244 	/* wait transfer completion */
245 	priv->error = regmap_read_poll_timeout(priv->regmap, TC358768_DSICMD_TX, val,
246 					       (val & TC358768_DSI_CMDTX_DC_START) == 0,
247 					       100, 100000);
248 }
249 
tc358768_sw_reset(struct tc358768_priv * priv)250 static int tc358768_sw_reset(struct tc358768_priv *priv)
251 {
252 	/* Assert Reset */
253 	tc358768_write(priv, TC358768_SYSCTL, 1);
254 	/* Release Reset, Exit Sleep */
255 	tc358768_write(priv, TC358768_SYSCTL, 0);
256 
257 	return tc358768_clear_error(priv);
258 }
259 
tc358768_hw_enable(struct tc358768_priv * priv)260 static void tc358768_hw_enable(struct tc358768_priv *priv)
261 {
262 	int ret;
263 
264 	if (priv->enabled)
265 		return;
266 
267 	ret = clk_prepare_enable(priv->refclk);
268 	if (ret < 0)
269 		dev_err(priv->dev, "error enabling refclk (%d)\n", ret);
270 
271 	ret = regulator_bulk_enable(ARRAY_SIZE(priv->supplies), priv->supplies);
272 	if (ret < 0)
273 		dev_err(priv->dev, "error enabling regulators (%d)\n", ret);
274 
275 	if (priv->reset_gpio)
276 		usleep_range(200, 300);
277 
278 	/*
279 	 * The RESX is active low (GPIO_ACTIVE_LOW).
280 	 * DEASSERT (value = 0) the reset_gpio to enable the chip
281 	 */
282 	gpiod_set_value_cansleep(priv->reset_gpio, 0);
283 
284 	/* wait for encoder clocks to stabilize */
285 	usleep_range(1000, 2000);
286 
287 	priv->enabled = true;
288 }
289 
tc358768_hw_disable(struct tc358768_priv * priv)290 static void tc358768_hw_disable(struct tc358768_priv *priv)
291 {
292 	int ret;
293 
294 	if (!priv->enabled)
295 		return;
296 
297 	/*
298 	 * The RESX is active low (GPIO_ACTIVE_LOW).
299 	 * ASSERT (value = 1) the reset_gpio to disable the chip
300 	 */
301 	gpiod_set_value_cansleep(priv->reset_gpio, 1);
302 
303 	ret = regulator_bulk_disable(ARRAY_SIZE(priv->supplies),
304 				     priv->supplies);
305 	if (ret < 0)
306 		dev_err(priv->dev, "error disabling regulators (%d)\n", ret);
307 
308 	clk_disable_unprepare(priv->refclk);
309 
310 	priv->enabled = false;
311 }
312 
tc358768_pll_to_pclk(struct tc358768_priv * priv,u32 pll_clk)313 static u32 tc358768_pll_to_pclk(struct tc358768_priv *priv, u32 pll_clk)
314 {
315 	return (u32)div_u64((u64)pll_clk * priv->dsi_lanes, priv->dsi_bpp);
316 }
317 
tc358768_pclk_to_pll(struct tc358768_priv * priv,u32 pclk)318 static u32 tc358768_pclk_to_pll(struct tc358768_priv *priv, u32 pclk)
319 {
320 	return (u32)div_u64((u64)pclk * priv->dsi_bpp, priv->dsi_lanes);
321 }
322 
tc358768_calc_pll(struct tc358768_priv * priv,const struct drm_display_mode * mode,bool verify_only)323 static int tc358768_calc_pll(struct tc358768_priv *priv,
324 			     const struct drm_display_mode *mode,
325 			     bool verify_only)
326 {
327 	static const u32 frs_limits[] = {
328 		1000000000,
329 		500000000,
330 		250000000,
331 		125000000,
332 		62500000
333 	};
334 	unsigned long refclk;
335 	u32 prd, target_pll, i, max_pll, min_pll;
336 	u32 frs, best_diff, best_pll, best_prd, best_fbd;
337 
338 	target_pll = tc358768_pclk_to_pll(priv, mode->clock * 1000);
339 
340 	/* pll_clk = RefClk * [(FBD + 1)/ (PRD + 1)] * [1 / (2^FRS)] */
341 
342 	for (i = 0; i < ARRAY_SIZE(frs_limits); i++)
343 		if (target_pll >= frs_limits[i])
344 			break;
345 
346 	if (i == ARRAY_SIZE(frs_limits) || i == 0)
347 		return -EINVAL;
348 
349 	frs = i - 1;
350 	max_pll = frs_limits[i - 1];
351 	min_pll = frs_limits[i];
352 
353 	refclk = clk_get_rate(priv->refclk);
354 
355 	best_diff = UINT_MAX;
356 	best_pll = 0;
357 	best_prd = 0;
358 	best_fbd = 0;
359 
360 	for (prd = 0; prd < 16; ++prd) {
361 		u32 divisor = (prd + 1) * (1 << frs);
362 		u32 fbd;
363 
364 		for (fbd = 0; fbd < 512; ++fbd) {
365 			u32 pll, diff, pll_in;
366 
367 			pll = (u32)div_u64((u64)refclk * (fbd + 1), divisor);
368 
369 			if (pll >= max_pll || pll < min_pll)
370 				continue;
371 
372 			pll_in = (u32)div_u64((u64)refclk, prd + 1);
373 			if (pll_in < 4000000)
374 				continue;
375 
376 			diff = max(pll, target_pll) - min(pll, target_pll);
377 
378 			if (diff < best_diff) {
379 				best_diff = diff;
380 				best_pll = pll;
381 				best_prd = prd;
382 				best_fbd = fbd;
383 
384 				if (best_diff == 0)
385 					goto found;
386 			}
387 		}
388 	}
389 
390 	if (best_diff == UINT_MAX) {
391 		dev_err(priv->dev, "could not find suitable PLL setup\n");
392 		return -EINVAL;
393 	}
394 
395 found:
396 	if (verify_only)
397 		return 0;
398 
399 	priv->fbd = best_fbd;
400 	priv->prd = best_prd;
401 	priv->frs = frs;
402 	priv->dsiclk = best_pll / 2;
403 	priv->pclk = mode->clock * 1000;
404 
405 	return 0;
406 }
407 
tc358768_dsi_host_attach(struct mipi_dsi_host * host,struct mipi_dsi_device * dev)408 static int tc358768_dsi_host_attach(struct mipi_dsi_host *host,
409 				    struct mipi_dsi_device *dev)
410 {
411 	struct tc358768_priv *priv = dsi_host_to_tc358768(host);
412 	struct drm_bridge *bridge;
413 	struct drm_panel *panel;
414 	struct device_node *ep;
415 	int ret;
416 
417 	if (dev->lanes > 4) {
418 		dev_err(priv->dev, "unsupported number of data lanes(%u)\n",
419 			dev->lanes);
420 		return -EINVAL;
421 	}
422 
423 	/*
424 	 * tc358768 supports both Video and Pulse mode, but the driver only
425 	 * implements Video (event) mode currently
426 	 */
427 	if (!(dev->mode_flags & MIPI_DSI_MODE_VIDEO)) {
428 		dev_err(priv->dev, "Only MIPI_DSI_MODE_VIDEO is supported\n");
429 		return -ENOTSUPP;
430 	}
431 
432 	/*
433 	 * tc358768 supports RGB888, RGB666, RGB666_PACKED and RGB565, but only
434 	 * RGB888 is verified.
435 	 */
436 	if (dev->format != MIPI_DSI_FMT_RGB888) {
437 		dev_warn(priv->dev, "Only MIPI_DSI_FMT_RGB888 tested!\n");
438 		return -ENOTSUPP;
439 	}
440 
441 	ret = drm_of_find_panel_or_bridge(host->dev->of_node, 1, 0, &panel,
442 					  &bridge);
443 	if (ret)
444 		return ret;
445 
446 	if (panel) {
447 		bridge = drm_panel_bridge_add_typed(panel,
448 						    DRM_MODE_CONNECTOR_DSI);
449 		if (IS_ERR(bridge))
450 			return PTR_ERR(bridge);
451 	}
452 
453 	priv->output.dev = dev;
454 	priv->output.bridge = bridge;
455 	priv->output.panel = panel;
456 
457 	priv->dsi_lanes = dev->lanes;
458 	priv->dsi_bpp = mipi_dsi_pixel_format_to_bpp(dev->format);
459 
460 	/* get input ep (port0/endpoint0) */
461 	ret = -EINVAL;
462 	ep = of_graph_get_endpoint_by_regs(host->dev->of_node, 0, 0);
463 	if (ep) {
464 		ret = of_property_read_u32(ep, "data-lines", &priv->pd_lines);
465 
466 		of_node_put(ep);
467 	}
468 
469 	if (ret)
470 		priv->pd_lines = priv->dsi_bpp;
471 
472 	drm_bridge_add(&priv->bridge);
473 
474 	return 0;
475 }
476 
tc358768_dsi_host_detach(struct mipi_dsi_host * host,struct mipi_dsi_device * dev)477 static int tc358768_dsi_host_detach(struct mipi_dsi_host *host,
478 				    struct mipi_dsi_device *dev)
479 {
480 	struct tc358768_priv *priv = dsi_host_to_tc358768(host);
481 
482 	drm_bridge_remove(&priv->bridge);
483 	if (priv->output.panel)
484 		drm_panel_bridge_remove(priv->output.bridge);
485 
486 	return 0;
487 }
488 
tc358768_dsi_host_transfer(struct mipi_dsi_host * host,const struct mipi_dsi_msg * msg)489 static ssize_t tc358768_dsi_host_transfer(struct mipi_dsi_host *host,
490 					  const struct mipi_dsi_msg *msg)
491 {
492 	struct tc358768_priv *priv = dsi_host_to_tc358768(host);
493 	struct mipi_dsi_packet packet;
494 	int ret;
495 
496 	if (!priv->enabled) {
497 		dev_err(priv->dev, "Bridge is not enabled\n");
498 		return -ENODEV;
499 	}
500 
501 	if (msg->rx_len) {
502 		dev_warn(priv->dev, "MIPI rx is not supported\n");
503 		return -ENOTSUPP;
504 	}
505 
506 	if (msg->tx_len > 8) {
507 		dev_warn(priv->dev, "Maximum 8 byte MIPI tx is supported\n");
508 		return -ENOTSUPP;
509 	}
510 
511 	ret = mipi_dsi_create_packet(&packet, msg);
512 	if (ret)
513 		return ret;
514 
515 	if (mipi_dsi_packet_format_is_short(msg->type)) {
516 		tc358768_write(priv, TC358768_DSICMD_TYPE,
517 			       (0x10 << 8) | (packet.header[0] & 0x3f));
518 		tc358768_write(priv, TC358768_DSICMD_WC, 0);
519 		tc358768_write(priv, TC358768_DSICMD_WD0,
520 			       (packet.header[2] << 8) | packet.header[1]);
521 	} else {
522 		int i;
523 
524 		tc358768_write(priv, TC358768_DSICMD_TYPE,
525 			       (0x40 << 8) | (packet.header[0] & 0x3f));
526 		tc358768_write(priv, TC358768_DSICMD_WC, packet.payload_length);
527 		for (i = 0; i < packet.payload_length; i += 2) {
528 			u16 val = packet.payload[i];
529 
530 			if (i + 1 < packet.payload_length)
531 				val |= packet.payload[i + 1] << 8;
532 
533 			tc358768_write(priv, TC358768_DSICMD_WD0 + i, val);
534 		}
535 	}
536 
537 	tc358768_dsicmd_tx(priv);
538 
539 	ret = tc358768_clear_error(priv);
540 	if (ret)
541 		dev_warn(priv->dev, "Software disable failed: %d\n", ret);
542 	else
543 		ret = packet.size;
544 
545 	return ret;
546 }
547 
548 static const struct mipi_dsi_host_ops tc358768_dsi_host_ops = {
549 	.attach = tc358768_dsi_host_attach,
550 	.detach = tc358768_dsi_host_detach,
551 	.transfer = tc358768_dsi_host_transfer,
552 };
553 
tc358768_bridge_attach(struct drm_bridge * bridge,enum drm_bridge_attach_flags flags)554 static int tc358768_bridge_attach(struct drm_bridge *bridge,
555 				  enum drm_bridge_attach_flags flags)
556 {
557 	struct tc358768_priv *priv = bridge_to_tc358768(bridge);
558 
559 	if (!drm_core_check_feature(bridge->dev, DRIVER_ATOMIC)) {
560 		dev_err(priv->dev, "needs atomic updates support\n");
561 		return -ENOTSUPP;
562 	}
563 
564 	return drm_bridge_attach(bridge->encoder, priv->output.bridge, bridge,
565 				 flags);
566 }
567 
568 static enum drm_mode_status
tc358768_bridge_mode_valid(struct drm_bridge * bridge,const struct drm_display_info * info,const struct drm_display_mode * mode)569 tc358768_bridge_mode_valid(struct drm_bridge *bridge,
570 			   const struct drm_display_info *info,
571 			   const struct drm_display_mode *mode)
572 {
573 	struct tc358768_priv *priv = bridge_to_tc358768(bridge);
574 
575 	if (tc358768_calc_pll(priv, mode, true))
576 		return MODE_CLOCK_RANGE;
577 
578 	return MODE_OK;
579 }
580 
tc358768_bridge_disable(struct drm_bridge * bridge)581 static void tc358768_bridge_disable(struct drm_bridge *bridge)
582 {
583 	struct tc358768_priv *priv = bridge_to_tc358768(bridge);
584 	int ret;
585 
586 	/* set FrmStop */
587 	tc358768_update_bits(priv, TC358768_PP_MISC, BIT(15), BIT(15));
588 
589 	/* wait at least for one frame */
590 	msleep(50);
591 
592 	/* clear PP_en */
593 	tc358768_update_bits(priv, TC358768_CONFCTL, BIT(6), 0);
594 
595 	/* set RstPtr */
596 	tc358768_update_bits(priv, TC358768_PP_MISC, BIT(14), BIT(14));
597 
598 	ret = tc358768_clear_error(priv);
599 	if (ret)
600 		dev_warn(priv->dev, "Software disable failed: %d\n", ret);
601 }
602 
tc358768_bridge_post_disable(struct drm_bridge * bridge)603 static void tc358768_bridge_post_disable(struct drm_bridge *bridge)
604 {
605 	struct tc358768_priv *priv = bridge_to_tc358768(bridge);
606 
607 	tc358768_hw_disable(priv);
608 }
609 
tc358768_setup_pll(struct tc358768_priv * priv,const struct drm_display_mode * mode)610 static int tc358768_setup_pll(struct tc358768_priv *priv,
611 			      const struct drm_display_mode *mode)
612 {
613 	u32 fbd, prd, frs;
614 	int ret;
615 
616 	ret = tc358768_calc_pll(priv, mode, false);
617 	if (ret) {
618 		dev_err(priv->dev, "PLL calculation failed: %d\n", ret);
619 		return ret;
620 	}
621 
622 	fbd = priv->fbd;
623 	prd = priv->prd;
624 	frs = priv->frs;
625 
626 	dev_dbg(priv->dev, "PLL: refclk %lu, fbd %u, prd %u, frs %u\n",
627 		clk_get_rate(priv->refclk), fbd, prd, frs);
628 	dev_dbg(priv->dev, "PLL: pll_clk: %u, DSIClk %u, HSByteClk %u\n",
629 		priv->dsiclk * 2, priv->dsiclk, priv->dsiclk / 4);
630 	dev_dbg(priv->dev, "PLL: pclk %u (panel: %u)\n",
631 		tc358768_pll_to_pclk(priv, priv->dsiclk * 2),
632 		mode->clock * 1000);
633 
634 	/* PRD[15:12] FBD[8:0] */
635 	tc358768_write(priv, TC358768_PLLCTL0, (prd << 12) | fbd);
636 
637 	/* FRS[11:10] LBWS[9:8] CKEN[4] RESETB[1] EN[0] */
638 	tc358768_write(priv, TC358768_PLLCTL1,
639 		       (frs << 10) | (0x2 << 8) | BIT(1) | BIT(0));
640 
641 	/* wait for lock */
642 	usleep_range(1000, 2000);
643 
644 	/* FRS[11:10] LBWS[9:8] CKEN[4] PLL_CKEN[4] RESETB[1] EN[0] */
645 	tc358768_write(priv, TC358768_PLLCTL1,
646 		       (frs << 10) | (0x2 << 8) | BIT(4) | BIT(1) | BIT(0));
647 
648 	return tc358768_clear_error(priv);
649 }
650 
tc358768_ns_to_cnt(u32 ns,u32 period_ps)651 static u32 tc358768_ns_to_cnt(u32 ns, u32 period_ps)
652 {
653 	return DIV_ROUND_UP(ns * 1000, period_ps);
654 }
655 
tc358768_ps_to_ns(u32 ps)656 static u32 tc358768_ps_to_ns(u32 ps)
657 {
658 	return ps / 1000;
659 }
660 
tc358768_dpi_to_ns(u32 val,u32 pclk)661 static u32 tc358768_dpi_to_ns(u32 val, u32 pclk)
662 {
663 	return (u32)div_u64((u64)val * NANO, pclk);
664 }
665 
666 /* Convert value in DPI pixel clock units to DSI byte count */
tc358768_dpi_to_dsi_bytes(struct tc358768_priv * priv,u32 val)667 static u32 tc358768_dpi_to_dsi_bytes(struct tc358768_priv *priv, u32 val)
668 {
669 	u64 m = (u64)val * priv->dsiclk / 4 * priv->dsi_lanes;
670 	u64 n = priv->pclk;
671 
672 	return (u32)div_u64(m + n - 1, n);
673 }
674 
tc358768_dsi_bytes_to_ns(struct tc358768_priv * priv,u32 val)675 static u32 tc358768_dsi_bytes_to_ns(struct tc358768_priv *priv, u32 val)
676 {
677 	u64 m = (u64)val * NANO;
678 	u64 n = priv->dsiclk / 4 * priv->dsi_lanes;
679 
680 	return (u32)div_u64(m, n);
681 }
682 
tc358768_bridge_pre_enable(struct drm_bridge * bridge)683 static void tc358768_bridge_pre_enable(struct drm_bridge *bridge)
684 {
685 	struct tc358768_priv *priv = bridge_to_tc358768(bridge);
686 	struct mipi_dsi_device *dsi_dev = priv->output.dev;
687 	unsigned long mode_flags = dsi_dev->mode_flags;
688 	u32 val, val2, lptxcnt, hact, data_type;
689 	s32 raw_val;
690 	const struct drm_display_mode *mode;
691 	u32 hsbyteclk_ps, dsiclk_ps, ui_ps;
692 	u32 dsiclk, hsbyteclk;
693 	int ret, i;
694 	struct videomode vm;
695 	struct device *dev = priv->dev;
696 	/* In pixelclock units */
697 	u32 dpi_htot, dpi_data_start;
698 	/* In byte units */
699 	u32 dsi_dpi_htot, dsi_dpi_data_start;
700 	u32 dsi_hsw, dsi_hbp, dsi_hact, dsi_hfp;
701 	const u32 dsi_hss = 4; /* HSS is a short packet (4 bytes) */
702 	/* In hsbyteclk units */
703 	u32 dsi_vsdly;
704 	const u32 internal_dly = 40;
705 
706 	if (mode_flags & MIPI_DSI_CLOCK_NON_CONTINUOUS) {
707 		dev_warn_once(dev, "Non-continuous mode unimplemented, falling back to continuous\n");
708 		mode_flags &= ~MIPI_DSI_CLOCK_NON_CONTINUOUS;
709 	}
710 
711 	tc358768_hw_enable(priv);
712 
713 	ret = tc358768_sw_reset(priv);
714 	if (ret) {
715 		dev_err(dev, "Software reset failed: %d\n", ret);
716 		tc358768_hw_disable(priv);
717 		return;
718 	}
719 
720 	mode = &bridge->encoder->crtc->state->adjusted_mode;
721 	ret = tc358768_setup_pll(priv, mode);
722 	if (ret) {
723 		dev_err(dev, "PLL setup failed: %d\n", ret);
724 		tc358768_hw_disable(priv);
725 		return;
726 	}
727 
728 	drm_display_mode_to_videomode(mode, &vm);
729 
730 	dsiclk = priv->dsiclk;
731 	hsbyteclk = dsiclk / 4;
732 
733 	/* Data Format Control Register */
734 	val = BIT(2) | BIT(1) | BIT(0); /* rdswap_en | dsitx_en | txdt_en */
735 	switch (dsi_dev->format) {
736 	case MIPI_DSI_FMT_RGB888:
737 		val |= (0x3 << 4);
738 		hact = vm.hactive * 3;
739 		data_type = MIPI_DSI_PACKED_PIXEL_STREAM_24;
740 		break;
741 	case MIPI_DSI_FMT_RGB666:
742 		val |= (0x4 << 4);
743 		hact = vm.hactive * 3;
744 		data_type = MIPI_DSI_PACKED_PIXEL_STREAM_18;
745 		break;
746 
747 	case MIPI_DSI_FMT_RGB666_PACKED:
748 		val |= (0x4 << 4) | BIT(3);
749 		hact = vm.hactive * 18 / 8;
750 		data_type = MIPI_DSI_PIXEL_STREAM_3BYTE_18;
751 		break;
752 
753 	case MIPI_DSI_FMT_RGB565:
754 		val |= (0x5 << 4);
755 		hact = vm.hactive * 2;
756 		data_type = MIPI_DSI_PACKED_PIXEL_STREAM_16;
757 		break;
758 	default:
759 		dev_err(dev, "Invalid data format (%u)\n",
760 			dsi_dev->format);
761 		tc358768_hw_disable(priv);
762 		return;
763 	}
764 
765 	/*
766 	 * There are three important things to make TC358768 work correctly,
767 	 * which are not trivial to manage:
768 	 *
769 	 * 1. Keep the DPI line-time and the DSI line-time as close to each
770 	 *    other as possible.
771 	 * 2. TC358768 goes to LP mode after each line's active area. The DSI
772 	 *    HFP period has to be long enough for entering and exiting LP mode.
773 	 *    But it is not clear how to calculate this.
774 	 * 3. VSDly (video start delay) has to be long enough to ensure that the
775 	 *    DSI TX does not start transmitting until we have started receiving
776 	 *    pixel data from the DPI input. It is not clear how to calculate
777 	 *    this either.
778 	 */
779 
780 	dpi_htot = vm.hactive + vm.hfront_porch + vm.hsync_len + vm.hback_porch;
781 	dpi_data_start = vm.hsync_len + vm.hback_porch;
782 
783 	dev_dbg(dev, "dpi horiz timing (pclk): %u + %u + %u + %u = %u\n",
784 		vm.hsync_len, vm.hback_porch, vm.hactive, vm.hfront_porch,
785 		dpi_htot);
786 
787 	dev_dbg(dev, "dpi horiz timing (ns): %u + %u + %u + %u = %u\n",
788 		tc358768_dpi_to_ns(vm.hsync_len, vm.pixelclock),
789 		tc358768_dpi_to_ns(vm.hback_porch, vm.pixelclock),
790 		tc358768_dpi_to_ns(vm.hactive, vm.pixelclock),
791 		tc358768_dpi_to_ns(vm.hfront_porch, vm.pixelclock),
792 		tc358768_dpi_to_ns(dpi_htot, vm.pixelclock));
793 
794 	dev_dbg(dev, "dpi data start (ns): %u + %u = %u\n",
795 		tc358768_dpi_to_ns(vm.hsync_len, vm.pixelclock),
796 		tc358768_dpi_to_ns(vm.hback_porch, vm.pixelclock),
797 		tc358768_dpi_to_ns(dpi_data_start, vm.pixelclock));
798 
799 	dsi_dpi_htot = tc358768_dpi_to_dsi_bytes(priv, dpi_htot);
800 	dsi_dpi_data_start = tc358768_dpi_to_dsi_bytes(priv, dpi_data_start);
801 
802 	if (dsi_dev->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE) {
803 		dsi_hsw = tc358768_dpi_to_dsi_bytes(priv, vm.hsync_len);
804 		dsi_hbp = tc358768_dpi_to_dsi_bytes(priv, vm.hback_porch);
805 	} else {
806 		/* HBP is included in HSW in event mode */
807 		dsi_hbp = 0;
808 		dsi_hsw = tc358768_dpi_to_dsi_bytes(priv,
809 						    vm.hsync_len +
810 						    vm.hback_porch);
811 
812 		/*
813 		 * The pixel packet includes the actual pixel data, and:
814 		 * DSI packet header = 4 bytes
815 		 * DCS code = 1 byte
816 		 * DSI packet footer = 2 bytes
817 		 */
818 		dsi_hact = hact + 4 + 1 + 2;
819 
820 		dsi_hfp = dsi_dpi_htot - dsi_hact - dsi_hsw - dsi_hss;
821 
822 		/*
823 		 * Here we should check if HFP is long enough for entering LP
824 		 * and exiting LP, but it's not clear how to calculate that.
825 		 * Instead, this is a naive algorithm that just adjusts the HFP
826 		 * and HSW so that HFP is (at least) roughly 2/3 of the total
827 		 * blanking time.
828 		 */
829 		if (dsi_hfp < (dsi_hfp + dsi_hsw + dsi_hss) * 2 / 3) {
830 			u32 old_hfp = dsi_hfp;
831 			u32 old_hsw = dsi_hsw;
832 			u32 tot = dsi_hfp + dsi_hsw + dsi_hss;
833 
834 			dsi_hsw = tot / 3;
835 
836 			/*
837 			 * Seems like sometimes HSW has to be divisible by num-lanes, but
838 			 * not always...
839 			 */
840 			dsi_hsw = roundup(dsi_hsw, priv->dsi_lanes);
841 
842 			dsi_hfp = dsi_dpi_htot - dsi_hact - dsi_hsw - dsi_hss;
843 
844 			dev_dbg(dev,
845 				"hfp too short, adjusting dsi hfp and dsi hsw from %u, %u to %u, %u\n",
846 				old_hfp, old_hsw, dsi_hfp, dsi_hsw);
847 		}
848 
849 		dev_dbg(dev,
850 			"dsi horiz timing (bytes): %u, %u + %u + %u + %u = %u\n",
851 			dsi_hss, dsi_hsw, dsi_hbp, dsi_hact, dsi_hfp,
852 			dsi_hss + dsi_hsw + dsi_hbp + dsi_hact + dsi_hfp);
853 
854 		dev_dbg(dev, "dsi horiz timing (ns): %u + %u + %u + %u + %u = %u\n",
855 			tc358768_dsi_bytes_to_ns(priv, dsi_hss),
856 			tc358768_dsi_bytes_to_ns(priv, dsi_hsw),
857 			tc358768_dsi_bytes_to_ns(priv, dsi_hbp),
858 			tc358768_dsi_bytes_to_ns(priv, dsi_hact),
859 			tc358768_dsi_bytes_to_ns(priv, dsi_hfp),
860 			tc358768_dsi_bytes_to_ns(priv, dsi_hss + dsi_hsw +
861 						 dsi_hbp + dsi_hact + dsi_hfp));
862 	}
863 
864 	/* VSDly calculation */
865 
866 	/* Start with the HW internal delay */
867 	dsi_vsdly = internal_dly;
868 
869 	/* Convert to byte units as the other variables are in byte units */
870 	dsi_vsdly *= priv->dsi_lanes;
871 
872 	/* Do we need more delay, in addition to the internal? */
873 	if (dsi_dpi_data_start > dsi_vsdly + dsi_hss + dsi_hsw + dsi_hbp) {
874 		dsi_vsdly = dsi_dpi_data_start - dsi_hss - dsi_hsw - dsi_hbp;
875 		dsi_vsdly = roundup(dsi_vsdly, priv->dsi_lanes);
876 	}
877 
878 	dev_dbg(dev, "dsi data start (bytes) %u + %u + %u + %u = %u\n",
879 		dsi_vsdly, dsi_hss, dsi_hsw, dsi_hbp,
880 		dsi_vsdly + dsi_hss + dsi_hsw + dsi_hbp);
881 
882 	dev_dbg(dev, "dsi data start (ns) %u + %u + %u + %u = %u\n",
883 		tc358768_dsi_bytes_to_ns(priv, dsi_vsdly),
884 		tc358768_dsi_bytes_to_ns(priv, dsi_hss),
885 		tc358768_dsi_bytes_to_ns(priv, dsi_hsw),
886 		tc358768_dsi_bytes_to_ns(priv, dsi_hbp),
887 		tc358768_dsi_bytes_to_ns(priv, dsi_vsdly + dsi_hss + dsi_hsw + dsi_hbp));
888 
889 	/* Convert back to hsbyteclk */
890 	dsi_vsdly /= priv->dsi_lanes;
891 
892 	/*
893 	 * The docs say that there is an internal delay of 40 cycles.
894 	 * However, we get underflows if we follow that rule. If we
895 	 * instead ignore the internal delay, things work. So either
896 	 * the docs are wrong or the calculations are wrong.
897 	 *
898 	 * As a temporary fix, add the internal delay here, to counter
899 	 * the subtraction when writing the register.
900 	 */
901 	dsi_vsdly += internal_dly;
902 
903 	/* Clamp to the register max */
904 	if (dsi_vsdly - internal_dly > 0x3ff) {
905 		dev_warn(dev, "VSDly too high, underflows likely\n");
906 		dsi_vsdly = 0x3ff + internal_dly;
907 	}
908 
909 	/* VSDly[9:0] */
910 	tc358768_write(priv, TC358768_VSDLY, dsi_vsdly - internal_dly);
911 
912 	tc358768_write(priv, TC358768_DATAFMT, val);
913 	tc358768_write(priv, TC358768_DSITX_DT, data_type);
914 
915 	/* Enable D-PHY (HiZ->LP11) */
916 	tc358768_write(priv, TC358768_CLW_CNTRL, 0x0000);
917 	/* Enable lanes */
918 	for (i = 0; i < dsi_dev->lanes; i++)
919 		tc358768_write(priv, TC358768_D0W_CNTRL + i * 4, 0x0000);
920 
921 	/* DSI Timings */
922 	hsbyteclk_ps = (u32)div_u64(PICO, hsbyteclk);
923 	dsiclk_ps = (u32)div_u64(PICO, dsiclk);
924 	ui_ps = dsiclk_ps / 2;
925 	dev_dbg(dev, "dsiclk: %u ps, ui %u ps, hsbyteclk %u ps\n", dsiclk_ps,
926 		ui_ps, hsbyteclk_ps);
927 
928 	/* LP11 > 100us for D-PHY Rx Init */
929 	val = tc358768_ns_to_cnt(100 * 1000, hsbyteclk_ps) - 1;
930 	dev_dbg(dev, "LINEINITCNT: %u\n", val);
931 	tc358768_write(priv, TC358768_LINEINITCNT, val);
932 
933 	/* LPTimeCnt > 50ns */
934 	val = tc358768_ns_to_cnt(50, hsbyteclk_ps) - 1;
935 	lptxcnt = val;
936 	dev_dbg(dev, "LPTXTIMECNT: %u\n", val);
937 	tc358768_write(priv, TC358768_LPTXTIMECNT, val);
938 
939 	/* 38ns < TCLK_PREPARE < 95ns */
940 	val = tc358768_ns_to_cnt(65, hsbyteclk_ps) - 1;
941 	dev_dbg(dev, "TCLK_PREPARECNT %u\n", val);
942 	/* TCLK_PREPARE + TCLK_ZERO > 300ns */
943 	val2 = tc358768_ns_to_cnt(300 - tc358768_ps_to_ns(2 * ui_ps),
944 				  hsbyteclk_ps) - 2;
945 	dev_dbg(dev, "TCLK_ZEROCNT %u\n", val2);
946 	val |= val2 << 8;
947 	tc358768_write(priv, TC358768_TCLK_HEADERCNT, val);
948 
949 	/* TCLK_TRAIL > 60ns AND TEOT <= 105 ns + 12*UI */
950 	raw_val = tc358768_ns_to_cnt(60 + tc358768_ps_to_ns(2 * ui_ps), hsbyteclk_ps) - 5;
951 	val = clamp(raw_val, 0, 127);
952 	dev_dbg(dev, "TCLK_TRAILCNT: %u\n", val);
953 	tc358768_write(priv, TC358768_TCLK_TRAILCNT, val);
954 
955 	/* 40ns + 4*UI < THS_PREPARE < 85ns + 6*UI */
956 	val = 50 + tc358768_ps_to_ns(4 * ui_ps);
957 	val = tc358768_ns_to_cnt(val, hsbyteclk_ps) - 1;
958 	dev_dbg(dev, "THS_PREPARECNT %u\n", val);
959 	/* THS_PREPARE + THS_ZERO > 145ns + 10*UI */
960 	raw_val = tc358768_ns_to_cnt(145 - tc358768_ps_to_ns(3 * ui_ps), hsbyteclk_ps) - 10;
961 	val2 = clamp(raw_val, 0, 127);
962 	dev_dbg(dev, "THS_ZEROCNT %u\n", val2);
963 	val |= val2 << 8;
964 	tc358768_write(priv, TC358768_THS_HEADERCNT, val);
965 
966 	/* TWAKEUP > 1ms in lptxcnt steps */
967 	val = tc358768_ns_to_cnt(1020000, hsbyteclk_ps);
968 	val = val / (lptxcnt + 1) - 1;
969 	dev_dbg(dev, "TWAKEUP: %u\n", val);
970 	tc358768_write(priv, TC358768_TWAKEUP, val);
971 
972 	/* TCLK_POSTCNT > 60ns + 52*UI */
973 	val = tc358768_ns_to_cnt(60 + tc358768_ps_to_ns(52 * ui_ps),
974 				 hsbyteclk_ps) - 3;
975 	dev_dbg(dev, "TCLK_POSTCNT: %u\n", val);
976 	tc358768_write(priv, TC358768_TCLK_POSTCNT, val);
977 
978 	/* max(60ns + 4*UI, 8*UI) < THS_TRAILCNT < 105ns + 12*UI */
979 	raw_val = tc358768_ns_to_cnt(60 + tc358768_ps_to_ns(18 * ui_ps),
980 				     hsbyteclk_ps) - 4;
981 	val = clamp(raw_val, 0, 15);
982 	dev_dbg(dev, "THS_TRAILCNT: %u\n", val);
983 	tc358768_write(priv, TC358768_THS_TRAILCNT, val);
984 
985 	val = BIT(0);
986 	for (i = 0; i < dsi_dev->lanes; i++)
987 		val |= BIT(i + 1);
988 	tc358768_write(priv, TC358768_HSTXVREGEN, val);
989 
990 	tc358768_write(priv, TC358768_TXOPTIONCNTRL,
991 		       (mode_flags & MIPI_DSI_CLOCK_NON_CONTINUOUS) ? 0 : BIT(0));
992 
993 	/* TXTAGOCNT[26:16] RXTASURECNT[10:0] */
994 	val = tc358768_ps_to_ns((lptxcnt + 1) * hsbyteclk_ps * 4);
995 	val = tc358768_ns_to_cnt(val, hsbyteclk_ps) / 4 - 1;
996 	dev_dbg(dev, "TXTAGOCNT: %u\n", val);
997 	val2 = tc358768_ns_to_cnt(tc358768_ps_to_ns((lptxcnt + 1) * hsbyteclk_ps),
998 				  hsbyteclk_ps) - 2;
999 	dev_dbg(dev, "RXTASURECNT: %u\n", val2);
1000 	val = val << 16 | val2;
1001 	tc358768_write(priv, TC358768_BTACNTRL1, val);
1002 
1003 	/* START[0] */
1004 	tc358768_write(priv, TC358768_STARTCNTRL, 1);
1005 
1006 	if (dsi_dev->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE) {
1007 		/* Set pulse mode */
1008 		tc358768_write(priv, TC358768_DSI_EVENT, 0);
1009 
1010 		/* vact */
1011 		tc358768_write(priv, TC358768_DSI_VACT, vm.vactive);
1012 
1013 		/* vsw */
1014 		tc358768_write(priv, TC358768_DSI_VSW, vm.vsync_len);
1015 
1016 		/* vbp */
1017 		tc358768_write(priv, TC358768_DSI_VBPR, vm.vback_porch);
1018 	} else {
1019 		/* Set event mode */
1020 		tc358768_write(priv, TC358768_DSI_EVENT, 1);
1021 
1022 		/* vact */
1023 		tc358768_write(priv, TC358768_DSI_VACT, vm.vactive);
1024 
1025 		/* vsw (+ vbp) */
1026 		tc358768_write(priv, TC358768_DSI_VSW,
1027 			       vm.vsync_len + vm.vback_porch);
1028 
1029 		/* vbp (not used in event mode) */
1030 		tc358768_write(priv, TC358768_DSI_VBPR, 0);
1031 	}
1032 
1033 	/* hsw (bytes) */
1034 	tc358768_write(priv, TC358768_DSI_HSW, dsi_hsw);
1035 
1036 	/* hbp (bytes) */
1037 	tc358768_write(priv, TC358768_DSI_HBPR, dsi_hbp);
1038 
1039 	/* hact (bytes) */
1040 	tc358768_write(priv, TC358768_DSI_HACT, hact);
1041 
1042 	/* VSYNC polarity */
1043 	tc358768_update_bits(priv, TC358768_CONFCTL, BIT(5),
1044 			     (mode->flags & DRM_MODE_FLAG_PVSYNC) ? BIT(5) : 0);
1045 
1046 	/* HSYNC polarity */
1047 	tc358768_update_bits(priv, TC358768_PP_MISC, BIT(0),
1048 			     (mode->flags & DRM_MODE_FLAG_PHSYNC) ? BIT(0) : 0);
1049 
1050 	/* Start DSI Tx */
1051 	tc358768_write(priv, TC358768_DSI_START, 0x1);
1052 
1053 	/* Configure DSI_Control register */
1054 	val = TC358768_DSI_CONFW_MODE_CLR | TC358768_DSI_CONFW_ADDR_DSI_CONTROL;
1055 	val |= TC358768_DSI_CONTROL_TXMD | TC358768_DSI_CONTROL_HSCKMD |
1056 	       0x3 << 1 | TC358768_DSI_CONTROL_EOTDIS;
1057 	tc358768_write(priv, TC358768_DSI_CONFW, val);
1058 
1059 	val = TC358768_DSI_CONFW_MODE_SET | TC358768_DSI_CONFW_ADDR_DSI_CONTROL;
1060 	val |= (dsi_dev->lanes - 1) << 1;
1061 
1062 	val |= TC358768_DSI_CONTROL_TXMD;
1063 
1064 	if (!(mode_flags & MIPI_DSI_CLOCK_NON_CONTINUOUS))
1065 		val |= TC358768_DSI_CONTROL_HSCKMD;
1066 
1067 	if (dsi_dev->mode_flags & MIPI_DSI_MODE_NO_EOT_PACKET)
1068 		val |= TC358768_DSI_CONTROL_EOTDIS;
1069 
1070 	tc358768_write(priv, TC358768_DSI_CONFW, val);
1071 
1072 	val = TC358768_DSI_CONFW_MODE_CLR | TC358768_DSI_CONFW_ADDR_DSI_CONTROL;
1073 	val |= TC358768_DSI_CONTROL_DIS_MODE; /* DSI mode */
1074 	tc358768_write(priv, TC358768_DSI_CONFW, val);
1075 
1076 	ret = tc358768_clear_error(priv);
1077 	if (ret) {
1078 		dev_err(dev, "Bridge pre_enable failed: %d\n", ret);
1079 		tc358768_bridge_disable(bridge);
1080 		tc358768_bridge_post_disable(bridge);
1081 	}
1082 }
1083 
tc358768_bridge_enable(struct drm_bridge * bridge)1084 static void tc358768_bridge_enable(struct drm_bridge *bridge)
1085 {
1086 	struct tc358768_priv *priv = bridge_to_tc358768(bridge);
1087 	int ret;
1088 
1089 	if (!priv->enabled) {
1090 		dev_err(priv->dev, "Bridge is not enabled\n");
1091 		return;
1092 	}
1093 
1094 	/* clear FrmStop and RstPtr */
1095 	tc358768_update_bits(priv, TC358768_PP_MISC, 0x3 << 14, 0);
1096 
1097 	/* set PP_en */
1098 	tc358768_update_bits(priv, TC358768_CONFCTL, BIT(6), BIT(6));
1099 
1100 	ret = tc358768_clear_error(priv);
1101 	if (ret) {
1102 		dev_err(priv->dev, "Bridge enable failed: %d\n", ret);
1103 		tc358768_bridge_disable(bridge);
1104 		tc358768_bridge_post_disable(bridge);
1105 	}
1106 }
1107 
1108 #define MAX_INPUT_SEL_FORMATS	1
1109 
1110 static u32 *
tc358768_atomic_get_input_bus_fmts(struct drm_bridge * bridge,struct drm_bridge_state * bridge_state,struct drm_crtc_state * crtc_state,struct drm_connector_state * conn_state,u32 output_fmt,unsigned int * num_input_fmts)1111 tc358768_atomic_get_input_bus_fmts(struct drm_bridge *bridge,
1112 				   struct drm_bridge_state *bridge_state,
1113 				   struct drm_crtc_state *crtc_state,
1114 				   struct drm_connector_state *conn_state,
1115 				   u32 output_fmt,
1116 				   unsigned int *num_input_fmts)
1117 {
1118 	struct tc358768_priv *priv = bridge_to_tc358768(bridge);
1119 	u32 *input_fmts;
1120 
1121 	*num_input_fmts = 0;
1122 
1123 	input_fmts = kcalloc(MAX_INPUT_SEL_FORMATS, sizeof(*input_fmts),
1124 			     GFP_KERNEL);
1125 	if (!input_fmts)
1126 		return NULL;
1127 
1128 	switch (priv->pd_lines) {
1129 	case 16:
1130 		input_fmts[0] = MEDIA_BUS_FMT_RGB565_1X16;
1131 		break;
1132 	case 18:
1133 		input_fmts[0] = MEDIA_BUS_FMT_RGB666_1X18;
1134 		break;
1135 	default:
1136 	case 24:
1137 		input_fmts[0] = MEDIA_BUS_FMT_RGB888_1X24;
1138 		break;
1139 	}
1140 
1141 	*num_input_fmts = MAX_INPUT_SEL_FORMATS;
1142 
1143 	return input_fmts;
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 	.pre_enable = tc358768_bridge_pre_enable,
1150 	.enable = tc358768_bridge_enable,
1151 	.disable = tc358768_bridge_disable,
1152 	.post_disable = tc358768_bridge_post_disable,
1153 
1154 	.atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
1155 	.atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
1156 	.atomic_reset = drm_atomic_helper_bridge_reset,
1157 	.atomic_get_input_bus_fmts = tc358768_atomic_get_input_bus_fmts,
1158 };
1159 
1160 static const struct drm_bridge_timings default_tc358768_timings = {
1161 	.input_bus_flags = DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE
1162 		 | DRM_BUS_FLAG_SYNC_SAMPLE_NEGEDGE
1163 		 | DRM_BUS_FLAG_DE_HIGH,
1164 };
1165 
tc358768_is_reserved_reg(unsigned int reg)1166 static bool tc358768_is_reserved_reg(unsigned int reg)
1167 {
1168 	switch (reg) {
1169 	case 0x114 ... 0x13f:
1170 	case 0x200:
1171 	case 0x20c:
1172 	case 0x400 ... 0x408:
1173 	case 0x41c ... 0x42f:
1174 		return true;
1175 	default:
1176 		return false;
1177 	}
1178 }
1179 
tc358768_writeable_reg(struct device * dev,unsigned int reg)1180 static bool tc358768_writeable_reg(struct device *dev, unsigned int reg)
1181 {
1182 	if (tc358768_is_reserved_reg(reg))
1183 		return false;
1184 
1185 	switch (reg) {
1186 	case TC358768_CHIPID:
1187 	case TC358768_FIFOSTATUS:
1188 	case TC358768_DSITXSTATUS ... (TC358768_DSITXSTATUS + 2):
1189 	case TC358768_DSI_CONTROL ... (TC358768_DSI_INT_ENA + 2):
1190 	case TC358768_DSICMD_RDFIFO ... (TC358768_DSI_ERR_HALT + 2):
1191 		return false;
1192 	default:
1193 		return true;
1194 	}
1195 }
1196 
tc358768_readable_reg(struct device * dev,unsigned int reg)1197 static bool tc358768_readable_reg(struct device *dev, unsigned int reg)
1198 {
1199 	if (tc358768_is_reserved_reg(reg))
1200 		return false;
1201 
1202 	switch (reg) {
1203 	case TC358768_STARTCNTRL:
1204 	case TC358768_DSI_CONFW ... (TC358768_DSI_CONFW + 2):
1205 	case TC358768_DSI_INT_CLR ... (TC358768_DSI_INT_CLR + 2):
1206 	case TC358768_DSI_START ... (TC358768_DSI_START + 2):
1207 	case TC358768_DBG_DATA:
1208 		return false;
1209 	default:
1210 		return true;
1211 	}
1212 }
1213 
1214 static const struct regmap_config tc358768_regmap_config = {
1215 	.name = "tc358768",
1216 	.reg_bits = 16,
1217 	.val_bits = 16,
1218 	.max_register = TC358768_DSI_HACT,
1219 	.cache_type = REGCACHE_NONE,
1220 	.writeable_reg = tc358768_writeable_reg,
1221 	.readable_reg = tc358768_readable_reg,
1222 	.reg_format_endian = REGMAP_ENDIAN_BIG,
1223 	.val_format_endian = REGMAP_ENDIAN_BIG,
1224 };
1225 
1226 static const struct i2c_device_id tc358768_i2c_ids[] = {
1227 	{ "tc358768", 0 },
1228 	{ "tc358778", 0 },
1229 	{ }
1230 };
1231 MODULE_DEVICE_TABLE(i2c, tc358768_i2c_ids);
1232 
1233 static const struct of_device_id tc358768_of_ids[] = {
1234 	{ .compatible = "toshiba,tc358768", },
1235 	{ .compatible = "toshiba,tc358778", },
1236 	{ }
1237 };
1238 MODULE_DEVICE_TABLE(of, tc358768_of_ids);
1239 
tc358768_get_regulators(struct tc358768_priv * priv)1240 static int tc358768_get_regulators(struct tc358768_priv *priv)
1241 {
1242 	int i, ret;
1243 
1244 	for (i = 0; i < ARRAY_SIZE(priv->supplies); ++i)
1245 		priv->supplies[i].supply = tc358768_supplies[i];
1246 
1247 	ret = devm_regulator_bulk_get(priv->dev, ARRAY_SIZE(priv->supplies),
1248 				      priv->supplies);
1249 	if (ret < 0)
1250 		dev_err(priv->dev, "failed to get regulators: %d\n", ret);
1251 
1252 	return ret;
1253 }
1254 
tc358768_i2c_probe(struct i2c_client * client)1255 static int tc358768_i2c_probe(struct i2c_client *client)
1256 {
1257 	struct tc358768_priv *priv;
1258 	struct device *dev = &client->dev;
1259 	struct device_node *np = dev->of_node;
1260 	int ret;
1261 
1262 	if (!np)
1263 		return -ENODEV;
1264 
1265 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
1266 	if (!priv)
1267 		return -ENOMEM;
1268 
1269 	dev_set_drvdata(dev, priv);
1270 	priv->dev = dev;
1271 
1272 	ret = tc358768_get_regulators(priv);
1273 	if (ret)
1274 		return ret;
1275 
1276 	priv->refclk = devm_clk_get(dev, "refclk");
1277 	if (IS_ERR(priv->refclk))
1278 		return PTR_ERR(priv->refclk);
1279 
1280 	/*
1281 	 * RESX is low active, to disable tc358768 initially (keep in reset)
1282 	 * the gpio line must be LOW. This is the ASSERTED state of
1283 	 * GPIO_ACTIVE_LOW (GPIOD_OUT_HIGH == ASSERTED).
1284 	 */
1285 	priv->reset_gpio  = devm_gpiod_get_optional(dev, "reset",
1286 						    GPIOD_OUT_HIGH);
1287 	if (IS_ERR(priv->reset_gpio))
1288 		return PTR_ERR(priv->reset_gpio);
1289 
1290 	priv->regmap = devm_regmap_init_i2c(client, &tc358768_regmap_config);
1291 	if (IS_ERR(priv->regmap)) {
1292 		dev_err(dev, "Failed to init regmap\n");
1293 		return PTR_ERR(priv->regmap);
1294 	}
1295 
1296 	priv->dsi_host.dev = dev;
1297 	priv->dsi_host.ops = &tc358768_dsi_host_ops;
1298 
1299 	priv->bridge.funcs = &tc358768_bridge_funcs;
1300 	priv->bridge.timings = &default_tc358768_timings;
1301 	priv->bridge.of_node = np;
1302 
1303 	i2c_set_clientdata(client, priv);
1304 
1305 	return mipi_dsi_host_register(&priv->dsi_host);
1306 }
1307 
tc358768_i2c_remove(struct i2c_client * client)1308 static void tc358768_i2c_remove(struct i2c_client *client)
1309 {
1310 	struct tc358768_priv *priv = i2c_get_clientdata(client);
1311 
1312 	mipi_dsi_host_unregister(&priv->dsi_host);
1313 }
1314 
1315 static struct i2c_driver tc358768_driver = {
1316 	.driver = {
1317 		.name = "tc358768",
1318 		.of_match_table = tc358768_of_ids,
1319 	},
1320 	.id_table = tc358768_i2c_ids,
1321 	.probe = tc358768_i2c_probe,
1322 	.remove	= tc358768_i2c_remove,
1323 };
1324 module_i2c_driver(tc358768_driver);
1325 
1326 MODULE_AUTHOR("Peter Ujfalusi <peter.ujfalusi@ti.com>");
1327 MODULE_DESCRIPTION("TC358768AXBG/TC358778XBG DSI bridge");
1328 MODULE_LICENSE("GPL v2");
1329