parade-ps8622.c 15.3 KB
Newer Older
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
/*
 * Parade PS8622 eDP/LVDS bridge driver
 *
 * Copyright (C) 2014 Google, Inc.
 *
 * This software is licensed under the terms of the GNU General Public
 * License version 2, as published by the Free Software Foundation, and
 * may be copied, distributed, and modified under those terms.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */

#include <linux/backlight.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/gpio.h>
20
#include <linux/gpio/consumer.h>
21 22 23 24 25 26 27
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/pm.h>
#include <linux/regulator/consumer.h>

28
#include <drm/drm_of.h>
29 30 31 32 33
#include <drm/drm_panel.h>

#include "drmP.h"
#include "drm_crtc.h"
#include "drm_crtc_helper.h"
34
#include "drm_atomic_helper.h"
35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480

/* Brightness scale on the Parade chip */
#define PS8622_MAX_BRIGHTNESS 0xff

/* Timings taken from the version 1.7 datasheet for the PS8622/PS8625 */
#define PS8622_POWER_RISE_T1_MIN_US 10
#define PS8622_POWER_RISE_T1_MAX_US 10000
#define PS8622_RST_HIGH_T2_MIN_US 3000
#define PS8622_RST_HIGH_T2_MAX_US 30000
#define PS8622_PWMO_END_T12_MS 200
#define PS8622_POWER_FALL_T16_MAX_US 10000
#define PS8622_POWER_OFF_T17_MS 500

#if ((PS8622_RST_HIGH_T2_MIN_US + PS8622_POWER_RISE_T1_MAX_US) > \
	(PS8622_RST_HIGH_T2_MAX_US + PS8622_POWER_RISE_T1_MIN_US))
#error "T2.min + T1.max must be less than T2.max + T1.min"
#endif

struct ps8622_bridge {
	struct drm_connector connector;
	struct i2c_client *client;
	struct drm_bridge bridge;
	struct drm_panel *panel;
	struct regulator *v12;
	struct backlight_device *bl;

	struct gpio_desc *gpio_slp;
	struct gpio_desc *gpio_rst;

	u32 max_lane_count;
	u32 lane_count;

	bool enabled;
};

static inline struct ps8622_bridge *
		bridge_to_ps8622(struct drm_bridge *bridge)
{
	return container_of(bridge, struct ps8622_bridge, bridge);
}

static inline struct ps8622_bridge *
		connector_to_ps8622(struct drm_connector *connector)
{
	return container_of(connector, struct ps8622_bridge, connector);
}

static int ps8622_set(struct i2c_client *client, u8 page, u8 reg, u8 val)
{
	int ret;
	struct i2c_adapter *adap = client->adapter;
	struct i2c_msg msg;
	u8 data[] = {reg, val};

	msg.addr = client->addr + page;
	msg.flags = 0;
	msg.len = sizeof(data);
	msg.buf = data;

	ret = i2c_transfer(adap, &msg, 1);
	if (ret != 1)
		pr_warn("PS8622 I2C write (0x%02x,0x%02x,0x%02x) failed: %d\n",
			client->addr + page, reg, val, ret);
	return !(ret == 1);
}

static int ps8622_send_config(struct ps8622_bridge *ps8622)
{
	struct i2c_client *cl = ps8622->client;
	int err = 0;

	/* HPD low */
	err = ps8622_set(cl, 0x02, 0xa1, 0x01);
	if (err)
		goto error;

	/* SW setting: [1:0] SW output 1.2V voltage is lower to 96% */
	err = ps8622_set(cl, 0x04, 0x14, 0x01);
	if (err)
		goto error;

	/* RCO SS setting: [5:4] = b01 0.5%, b10 1%, b11 1.5% */
	err = ps8622_set(cl, 0x04, 0xe3, 0x20);
	if (err)
		goto error;

	/* [7] RCO SS enable */
	err = ps8622_set(cl, 0x04, 0xe2, 0x80);
	if (err)
		goto error;

	/* RPHY Setting
	 * [3:2] CDR tune wait cycle before measure for fine tune
	 * b00: 1us b01: 0.5us b10:2us, b11: 4us
	 */
	err = ps8622_set(cl, 0x04, 0x8a, 0x0c);
	if (err)
		goto error;

	/* [3] RFD always on */
	err = ps8622_set(cl, 0x04, 0x89, 0x08);
	if (err)
		goto error;

	/* CTN lock in/out: 20000ppm/80000ppm. Lock out 2 times. */
	err = ps8622_set(cl, 0x04, 0x71, 0x2d);
	if (err)
		goto error;

	/* 2.7G CDR settings: NOF=40LSB for HBR CDR  setting */
	err = ps8622_set(cl, 0x04, 0x7d, 0x07);
	if (err)
		goto error;

	/* [1:0] Fmin=+4bands */
	err = ps8622_set(cl, 0x04, 0x7b, 0x00);
	if (err)
		goto error;

	/* [7:5] DCO_FTRNG=+-40% */
	err = ps8622_set(cl, 0x04, 0x7a, 0xfd);
	if (err)
		goto error;

	/* 1.62G CDR settings: [5:2]NOF=64LSB [1:0]DCO scale is 2/5 */
	err = ps8622_set(cl, 0x04, 0xc0, 0x12);
	if (err)
		goto error;

	/* Gitune=-37% */
	err = ps8622_set(cl, 0x04, 0xc1, 0x92);
	if (err)
		goto error;

	/* Fbstep=100% */
	err = ps8622_set(cl, 0x04, 0xc2, 0x1c);
	if (err)
		goto error;

	/* [7] LOS signal disable */
	err = ps8622_set(cl, 0x04, 0x32, 0x80);
	if (err)
		goto error;

	/* RPIO Setting: [7:4] LVDS driver bias current : 75% (250mV swing) */
	err = ps8622_set(cl, 0x04, 0x00, 0xb0);
	if (err)
		goto error;

	/* [7:6] Right-bar GPIO output strength is 8mA */
	err = ps8622_set(cl, 0x04, 0x15, 0x40);
	if (err)
		goto error;

	/* EQ Training State Machine Setting, RCO calibration start */
	err = ps8622_set(cl, 0x04, 0x54, 0x10);
	if (err)
		goto error;

	/* Logic, needs more than 10 I2C command */
	/* [4:0] MAX_LANE_COUNT set to max supported lanes */
	err = ps8622_set(cl, 0x01, 0x02, 0x80 | ps8622->max_lane_count);
	if (err)
		goto error;

	/* [4:0] LANE_COUNT_SET set to chosen lane count */
	err = ps8622_set(cl, 0x01, 0x21, 0x80 | ps8622->lane_count);
	if (err)
		goto error;

	err = ps8622_set(cl, 0x00, 0x52, 0x20);
	if (err)
		goto error;

	/* HPD CP toggle enable */
	err = ps8622_set(cl, 0x00, 0xf1, 0x03);
	if (err)
		goto error;

	err = ps8622_set(cl, 0x00, 0x62, 0x41);
	if (err)
		goto error;

	/* Counter number, add 1ms counter delay */
	err = ps8622_set(cl, 0x00, 0xf6, 0x01);
	if (err)
		goto error;

	/* [6]PWM function control by DPCD0040f[7], default is PWM block */
	err = ps8622_set(cl, 0x00, 0x77, 0x06);
	if (err)
		goto error;

	/* 04h Adjust VTotal toleranceto fix the 30Hz no display issue */
	err = ps8622_set(cl, 0x00, 0x4c, 0x04);
	if (err)
		goto error;

	/* DPCD00400='h00, Parade OUI ='h001cf8 */
	err = ps8622_set(cl, 0x01, 0xc0, 0x00);
	if (err)
		goto error;

	/* DPCD00401='h1c */
	err = ps8622_set(cl, 0x01, 0xc1, 0x1c);
	if (err)
		goto error;

	/* DPCD00402='hf8 */
	err = ps8622_set(cl, 0x01, 0xc2, 0xf8);
	if (err)
		goto error;

	/* DPCD403~408 = ASCII code, D2SLV5='h4432534c5635 */
	err = ps8622_set(cl, 0x01, 0xc3, 0x44);
	if (err)
		goto error;

	/* DPCD404 */
	err = ps8622_set(cl, 0x01, 0xc4, 0x32);
	if (err)
		goto error;

	/* DPCD405 */
	err = ps8622_set(cl, 0x01, 0xc5, 0x53);
	if (err)
		goto error;

	/* DPCD406 */
	err = ps8622_set(cl, 0x01, 0xc6, 0x4c);
	if (err)
		goto error;

	/* DPCD407 */
	err = ps8622_set(cl, 0x01, 0xc7, 0x56);
	if (err)
		goto error;

	/* DPCD408 */
	err = ps8622_set(cl, 0x01, 0xc8, 0x35);
	if (err)
		goto error;

	/* DPCD40A, Initial Code major revision '01' */
	err = ps8622_set(cl, 0x01, 0xca, 0x01);
	if (err)
		goto error;

	/* DPCD40B, Initial Code minor revision '05' */
	err = ps8622_set(cl, 0x01, 0xcb, 0x05);
	if (err)
		goto error;


	if (ps8622->bl) {
		/* DPCD720, internal PWM */
		err = ps8622_set(cl, 0x01, 0xa5, 0xa0);
		if (err)
			goto error;

		/* FFh for 100% brightness, 0h for 0% brightness */
		err = ps8622_set(cl, 0x01, 0xa7,
				ps8622->bl->props.brightness);
		if (err)
			goto error;
	} else {
		/* DPCD720, external PWM */
		err = ps8622_set(cl, 0x01, 0xa5, 0x80);
		if (err)
			goto error;
	}

	/* Set LVDS output as 6bit-VESA mapping, single LVDS channel */
	err = ps8622_set(cl, 0x01, 0xcc, 0x13);
	if (err)
		goto error;

	/* Enable SSC set by register */
	err = ps8622_set(cl, 0x02, 0xb1, 0x20);
	if (err)
		goto error;

	/* Set SSC enabled and +/-1% central spreading */
	err = ps8622_set(cl, 0x04, 0x10, 0x16);
	if (err)
		goto error;

	/* Logic end */
	/* MPU Clock source: LC => RCO */
	err = ps8622_set(cl, 0x04, 0x59, 0x60);
	if (err)
		goto error;

	/* LC -> RCO */
	err = ps8622_set(cl, 0x04, 0x54, 0x14);
	if (err)
		goto error;

	/* HPD high */
	err = ps8622_set(cl, 0x02, 0xa1, 0x91);

error:
	return err ? -EIO : 0;
}

static int ps8622_backlight_update(struct backlight_device *bl)
{
	struct ps8622_bridge *ps8622 = dev_get_drvdata(&bl->dev);
	int ret, brightness = bl->props.brightness;

	if (bl->props.power != FB_BLANK_UNBLANK ||
	    bl->props.state & (BL_CORE_SUSPENDED | BL_CORE_FBBLANK))
		brightness = 0;

	if (!ps8622->enabled)
		return -EINVAL;

	ret = ps8622_set(ps8622->client, 0x01, 0xa7, brightness);

	return ret;
}

static const struct backlight_ops ps8622_backlight_ops = {
	.update_status	= ps8622_backlight_update,
};

static void ps8622_pre_enable(struct drm_bridge *bridge)
{
	struct ps8622_bridge *ps8622 = bridge_to_ps8622(bridge);
	int ret;

	if (ps8622->enabled)
		return;

	gpiod_set_value(ps8622->gpio_rst, 0);

	if (ps8622->v12) {
		ret = regulator_enable(ps8622->v12);
		if (ret)
			DRM_ERROR("fails to enable ps8622->v12");
	}

	if (drm_panel_prepare(ps8622->panel)) {
		DRM_ERROR("failed to prepare panel\n");
		return;
	}

	gpiod_set_value(ps8622->gpio_slp, 1);

	/*
	 * T1 is the range of time that it takes for the power to rise after we
	 * enable the lcd/ps8622 fet. T2 is the range of time in which the
	 * data sheet specifies we should deassert the reset pin.
	 *
	 * If it takes T1.max for the power to rise, we need to wait atleast
	 * T2.min before deasserting the reset pin. If it takes T1.min for the
	 * power to rise, we need to wait at most T2.max before deasserting the
	 * reset pin.
	 */
	usleep_range(PS8622_RST_HIGH_T2_MIN_US + PS8622_POWER_RISE_T1_MAX_US,
		     PS8622_RST_HIGH_T2_MAX_US + PS8622_POWER_RISE_T1_MIN_US);

	gpiod_set_value(ps8622->gpio_rst, 1);

	/* wait 20ms after RST high */
	usleep_range(20000, 30000);

	ret = ps8622_send_config(ps8622);
	if (ret) {
		DRM_ERROR("Failed to send config to bridge (%d)\n", ret);
		return;
	}

	ps8622->enabled = true;
}

static void ps8622_enable(struct drm_bridge *bridge)
{
	struct ps8622_bridge *ps8622 = bridge_to_ps8622(bridge);

	if (drm_panel_enable(ps8622->panel)) {
		DRM_ERROR("failed to enable panel\n");
		return;
	}
}

static void ps8622_disable(struct drm_bridge *bridge)
{
	struct ps8622_bridge *ps8622 = bridge_to_ps8622(bridge);

	if (drm_panel_disable(ps8622->panel)) {
		DRM_ERROR("failed to disable panel\n");
		return;
	}
	msleep(PS8622_PWMO_END_T12_MS);
}

static void ps8622_post_disable(struct drm_bridge *bridge)
{
	struct ps8622_bridge *ps8622 = bridge_to_ps8622(bridge);

	if (!ps8622->enabled)
		return;

	ps8622->enabled = false;

	/*
	 * This doesn't matter if the regulators are turned off, but something
	 * else might keep them on. In that case, we want to assert the slp gpio
	 * to lower power.
	 */
	gpiod_set_value(ps8622->gpio_slp, 0);

	if (drm_panel_unprepare(ps8622->panel)) {
		DRM_ERROR("failed to unprepare panel\n");
		return;
	}

	if (ps8622->v12)
		regulator_disable(ps8622->v12);

	/*
	 * Sleep for at least the amount of time that it takes the power rail to
	 * fall to prevent asserting the rst gpio from doing anything.
	 */
	usleep_range(PS8622_POWER_FALL_T16_MAX_US,
		     2 * PS8622_POWER_FALL_T16_MAX_US);
	gpiod_set_value(ps8622->gpio_rst, 0);

	msleep(PS8622_POWER_OFF_T17_MS);
}

static int ps8622_get_modes(struct drm_connector *connector)
{
	struct ps8622_bridge *ps8622;

	ps8622 = connector_to_ps8622(connector);

	return drm_panel_get_modes(ps8622->panel);
}

static const struct drm_connector_helper_funcs ps8622_connector_helper_funcs = {
	.get_modes = ps8622_get_modes,
};

static const struct drm_connector_funcs ps8622_connector_funcs = {
481
	.dpms = drm_atomic_helper_connector_dpms,
482
	.fill_modes = drm_helper_probe_single_connector_modes,
483
	.destroy = drm_connector_cleanup,
484 485 486
	.reset = drm_atomic_helper_connector_reset,
	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
487 488
};

489
static int ps8622_attach(struct drm_bridge *bridge)
490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545
{
	struct ps8622_bridge *ps8622 = bridge_to_ps8622(bridge);
	int ret;

	if (!bridge->encoder) {
		DRM_ERROR("Parent encoder object not found");
		return -ENODEV;
	}

	ps8622->connector.polled = DRM_CONNECTOR_POLL_HPD;
	ret = drm_connector_init(bridge->dev, &ps8622->connector,
			&ps8622_connector_funcs, DRM_MODE_CONNECTOR_LVDS);
	if (ret) {
		DRM_ERROR("Failed to initialize connector with drm\n");
		return ret;
	}
	drm_connector_helper_add(&ps8622->connector,
					&ps8622_connector_helper_funcs);
	drm_connector_register(&ps8622->connector);
	drm_mode_connector_attach_encoder(&ps8622->connector,
							bridge->encoder);

	if (ps8622->panel)
		drm_panel_attach(ps8622->panel, &ps8622->connector);

	drm_helper_hpd_irq_event(ps8622->connector.dev);

	return ret;
}

static const struct drm_bridge_funcs ps8622_bridge_funcs = {
	.pre_enable = ps8622_pre_enable,
	.enable = ps8622_enable,
	.disable = ps8622_disable,
	.post_disable = ps8622_post_disable,
	.attach = ps8622_attach,
};

static const struct of_device_id ps8622_devices[] = {
	{.compatible = "parade,ps8622",},
	{.compatible = "parade,ps8625",},
	{}
};
MODULE_DEVICE_TABLE(of, ps8622_devices);

static int ps8622_probe(struct i2c_client *client,
					const struct i2c_device_id *id)
{
	struct device *dev = &client->dev;
	struct ps8622_bridge *ps8622;
	int ret;

	ps8622 = devm_kzalloc(dev, sizeof(*ps8622), GFP_KERNEL);
	if (!ps8622)
		return -ENOMEM;

546 547 548
	ret = drm_of_find_panel_or_bridge(dev->of_node, 0, 0, &ps8622->panel, NULL);
	if (ret)
		return ret;
549 550 551 552 553 554 555 556 557

	ps8622->client = client;

	ps8622->v12 = devm_regulator_get(dev, "vdd12");
	if (IS_ERR(ps8622->v12)) {
		dev_info(dev, "no 1.2v regulator found for PS8622\n");
		ps8622->v12 = NULL;
	}

558
	ps8622->gpio_slp = devm_gpiod_get(dev, "sleep", GPIOD_OUT_HIGH);
559 560 561 562 563 564 565 566 567 568
	if (IS_ERR(ps8622->gpio_slp)) {
		ret = PTR_ERR(ps8622->gpio_slp);
		dev_err(dev, "cannot get gpio_slp %d\n", ret);
		return ret;
	}

	/*
	 * Assert the reset pin high to avoid the bridge being
	 * initialized prematurely
	 */
569 570 571 572
	ps8622->gpio_rst = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
	if (IS_ERR(ps8622->gpio_rst)) {
		ret = PTR_ERR(ps8622->gpio_rst);
		dev_err(dev, "cannot get gpio_rst %d\n", ret);
573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617
		return ret;
	}

	ps8622->max_lane_count = id->driver_data;

	if (of_property_read_u32(dev->of_node, "lane-count",
						&ps8622->lane_count)) {
		ps8622->lane_count = ps8622->max_lane_count;
	} else if (ps8622->lane_count > ps8622->max_lane_count) {
		dev_info(dev, "lane-count property is too high,"
						"using max_lane_count\n");
		ps8622->lane_count = ps8622->max_lane_count;
	}

	if (!of_find_property(dev->of_node, "use-external-pwm", NULL)) {
		ps8622->bl = backlight_device_register("ps8622-backlight",
				dev, ps8622, &ps8622_backlight_ops,
				NULL);
		if (IS_ERR(ps8622->bl)) {
			DRM_ERROR("failed to register backlight\n");
			ret = PTR_ERR(ps8622->bl);
			ps8622->bl = NULL;
			return ret;
		}
		ps8622->bl->props.max_brightness = PS8622_MAX_BRIGHTNESS;
		ps8622->bl->props.brightness = PS8622_MAX_BRIGHTNESS;
	}

	ps8622->bridge.funcs = &ps8622_bridge_funcs;
	ps8622->bridge.of_node = dev->of_node;
	ret = drm_bridge_add(&ps8622->bridge);
	if (ret) {
		DRM_ERROR("Failed to add bridge\n");
		return ret;
	}

	i2c_set_clientdata(client, ps8622);

	return 0;
}

static int ps8622_remove(struct i2c_client *client)
{
	struct ps8622_bridge *ps8622 = i2c_get_clientdata(client);

618
	backlight_device_unregister(ps8622->bl);
619 620 621 622 623 624 625 626 627 628 629 630 631
	drm_bridge_remove(&ps8622->bridge);

	return 0;
}

static const struct i2c_device_id ps8622_i2c_table[] = {
	/* Device type, max_lane_count */
	{"ps8622", 1},
	{"ps8625", 2},
	{},
};
MODULE_DEVICE_TABLE(i2c, ps8622_i2c_table);

632
static struct i2c_driver ps8622_driver = {
633 634 635 636 637 638 639 640 641 642 643 644 645
	.id_table	= ps8622_i2c_table,
	.probe		= ps8622_probe,
	.remove		= ps8622_remove,
	.driver		= {
		.name	= "ps8622",
		.of_match_table = ps8622_devices,
	},
};
module_i2c_driver(ps8622_driver);

MODULE_AUTHOR("Vincent Palatin <vpalatin@chromium.org>");
MODULE_DESCRIPTION("Parade ps8622/ps8625 eDP-LVDS converter driver");
MODULE_LICENSE("GPL v2");