xref: /linux/drivers/gpu/drm/bridge/analogix/analogix-anx6345.c (revision 6fdcba32711044c35c0e1b094cbd8f3f0b4472c9)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Copyright(c) 2016, Analogix Semiconductor.
4  * Copyright(c) 2017, Icenowy Zheng <icenowy@aosc.io>
5  *
6  * Based on anx7808 driver obtained from chromeos with copyright:
7  * Copyright(c) 2013, Google Inc.
8  */
9 #include <linux/delay.h>
10 #include <linux/err.h>
11 #include <linux/gpio/consumer.h>
12 #include <linux/i2c.h>
13 #include <linux/interrupt.h>
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/of_platform.h>
17 #include <linux/regmap.h>
18 #include <linux/regulator/consumer.h>
19 #include <linux/types.h>
20 
21 #include <drm/drm_atomic_helper.h>
22 #include <drm/drm_bridge.h>
23 #include <drm/drm_crtc.h>
24 #include <drm/drm_crtc_helper.h>
25 #include <drm/drm_dp_helper.h>
26 #include <drm/drm_edid.h>
27 #include <drm/drm_of.h>
28 #include <drm/drm_panel.h>
29 #include <drm/drm_print.h>
30 #include <drm/drm_probe_helper.h>
31 
32 #include "analogix-i2c-dptx.h"
33 #include "analogix-i2c-txcommon.h"
34 
35 #define POLL_DELAY		50000 /* us */
36 #define POLL_TIMEOUT		5000000 /* us */
37 
38 #define I2C_IDX_DPTX		0
39 #define I2C_IDX_TXCOM		1
40 
41 static const u8 anx6345_i2c_addresses[] = {
42 	[I2C_IDX_DPTX]	= 0x70,
43 	[I2C_IDX_TXCOM]	= 0x72,
44 };
45 #define I2C_NUM_ADDRESSES	ARRAY_SIZE(anx6345_i2c_addresses)
46 
47 struct anx6345 {
48 	struct drm_dp_aux aux;
49 	struct drm_bridge bridge;
50 	struct i2c_client *client;
51 	struct edid *edid;
52 	struct drm_connector connector;
53 	struct drm_panel *panel;
54 	struct regulator *dvdd12;
55 	struct regulator *dvdd25;
56 	struct gpio_desc *gpiod_reset;
57 	struct mutex lock;	/* protect EDID access */
58 
59 	/* I2C Slave addresses of ANX6345 are mapped as DPTX and SYS */
60 	struct i2c_client *i2c_clients[I2C_NUM_ADDRESSES];
61 	struct regmap *map[I2C_NUM_ADDRESSES];
62 
63 	u16 chipid;
64 	u8 dpcd[DP_RECEIVER_CAP_SIZE];
65 
66 	bool powered;
67 };
68 
69 static inline struct anx6345 *connector_to_anx6345(struct drm_connector *c)
70 {
71 	return container_of(c, struct anx6345, connector);
72 }
73 
74 static inline struct anx6345 *bridge_to_anx6345(struct drm_bridge *bridge)
75 {
76 	return container_of(bridge, struct anx6345, bridge);
77 }
78 
79 static int anx6345_set_bits(struct regmap *map, u8 reg, u8 mask)
80 {
81 	return regmap_update_bits(map, reg, mask, mask);
82 }
83 
84 static int anx6345_clear_bits(struct regmap *map, u8 reg, u8 mask)
85 {
86 	return regmap_update_bits(map, reg, mask, 0);
87 }
88 
89 static ssize_t anx6345_aux_transfer(struct drm_dp_aux *aux,
90 				    struct drm_dp_aux_msg *msg)
91 {
92 	struct anx6345 *anx6345 = container_of(aux, struct anx6345, aux);
93 
94 	return anx_dp_aux_transfer(anx6345->map[I2C_IDX_DPTX], msg);
95 }
96 
97 static int anx6345_dp_link_training(struct anx6345 *anx6345)
98 {
99 	unsigned int value;
100 	u8 dp_bw, dpcd[2];
101 	int err;
102 
103 	err = anx6345_clear_bits(anx6345->map[I2C_IDX_TXCOM],
104 				 SP_POWERDOWN_CTRL_REG,
105 				 SP_TOTAL_PD);
106 	if (err)
107 		return err;
108 
109 	err = drm_dp_dpcd_readb(&anx6345->aux, DP_MAX_LINK_RATE, &dp_bw);
110 	if (err < 0)
111 		return err;
112 
113 	switch (dp_bw) {
114 	case DP_LINK_BW_1_62:
115 	case DP_LINK_BW_2_7:
116 		break;
117 
118 	default:
119 		DRM_DEBUG_KMS("DP bandwidth (%#02x) not supported\n", dp_bw);
120 		return -EINVAL;
121 	}
122 
123 	err = anx6345_set_bits(anx6345->map[I2C_IDX_TXCOM], SP_VID_CTRL1_REG,
124 			       SP_VIDEO_MUTE);
125 	if (err)
126 		return err;
127 
128 	err = anx6345_clear_bits(anx6345->map[I2C_IDX_TXCOM],
129 				 SP_VID_CTRL1_REG, SP_VIDEO_EN);
130 	if (err)
131 		return err;
132 
133 	/* Get DPCD info */
134 	err = drm_dp_dpcd_read(&anx6345->aux, DP_DPCD_REV,
135 			       &anx6345->dpcd, DP_RECEIVER_CAP_SIZE);
136 	if (err < 0) {
137 		DRM_ERROR("Failed to read DPCD: %d\n", err);
138 		return err;
139 	}
140 
141 	/* Clear channel x SERDES power down */
142 	err = anx6345_clear_bits(anx6345->map[I2C_IDX_DPTX],
143 				 SP_DP_ANALOG_POWER_DOWN_REG, SP_CH0_PD);
144 	if (err)
145 		return err;
146 
147 	/*
148 	 * Power up the sink (DP_SET_POWER register is only available on DPCD
149 	 * v1.1 and later).
150 	 */
151 	if (anx6345->dpcd[DP_DPCD_REV] >= 0x11) {
152 		err = drm_dp_dpcd_readb(&anx6345->aux, DP_SET_POWER, &dpcd[0]);
153 		if (err < 0) {
154 			DRM_ERROR("Failed to read DP_SET_POWER register: %d\n",
155 				  err);
156 			return err;
157 		}
158 
159 		dpcd[0] &= ~DP_SET_POWER_MASK;
160 		dpcd[0] |= DP_SET_POWER_D0;
161 
162 		err = drm_dp_dpcd_writeb(&anx6345->aux, DP_SET_POWER, dpcd[0]);
163 		if (err < 0) {
164 			DRM_ERROR("Failed to power up DisplayPort link: %d\n",
165 				  err);
166 			return err;
167 		}
168 
169 		/*
170 		 * According to the DP 1.1 specification, a "Sink Device must
171 		 * exit the power saving state within 1 ms" (Section 2.5.3.1,
172 		 * Table 5-52, "Sink Control Field" (register 0x600).
173 		 */
174 		usleep_range(1000, 2000);
175 	}
176 
177 	/* Possibly enable downspread on the sink */
178 	err = regmap_write(anx6345->map[I2C_IDX_DPTX],
179 			   SP_DP_DOWNSPREAD_CTRL1_REG, 0);
180 	if (err)
181 		return err;
182 
183 	if (anx6345->dpcd[DP_MAX_DOWNSPREAD] & DP_MAX_DOWNSPREAD_0_5) {
184 		DRM_DEBUG("Enable downspread on the sink\n");
185 		/* 4000PPM */
186 		err = regmap_write(anx6345->map[I2C_IDX_DPTX],
187 				   SP_DP_DOWNSPREAD_CTRL1_REG, 8);
188 		if (err)
189 			return err;
190 
191 		err = drm_dp_dpcd_writeb(&anx6345->aux, DP_DOWNSPREAD_CTRL,
192 					 DP_SPREAD_AMP_0_5);
193 		if (err < 0)
194 			return err;
195 	} else {
196 		err = drm_dp_dpcd_writeb(&anx6345->aux, DP_DOWNSPREAD_CTRL, 0);
197 		if (err < 0)
198 			return err;
199 	}
200 
201 	/* Set the lane count and the link rate on the sink */
202 	if (drm_dp_enhanced_frame_cap(anx6345->dpcd))
203 		err = anx6345_set_bits(anx6345->map[I2C_IDX_DPTX],
204 				       SP_DP_SYSTEM_CTRL_BASE + 4,
205 				       SP_ENHANCED_MODE);
206 	else
207 		err = anx6345_clear_bits(anx6345->map[I2C_IDX_DPTX],
208 					 SP_DP_SYSTEM_CTRL_BASE + 4,
209 					 SP_ENHANCED_MODE);
210 	if (err)
211 		return err;
212 
213 	dpcd[0] = drm_dp_max_link_rate(anx6345->dpcd);
214 	dpcd[0] = drm_dp_link_rate_to_bw_code(dpcd[0]);
215 	err = regmap_write(anx6345->map[I2C_IDX_DPTX],
216 			   SP_DP_MAIN_LINK_BW_SET_REG, dpcd[0]);
217 	if (err)
218 		return err;
219 
220 	dpcd[1] = drm_dp_max_lane_count(anx6345->dpcd);
221 
222 	err = regmap_write(anx6345->map[I2C_IDX_DPTX],
223 			   SP_DP_LANE_COUNT_SET_REG, dpcd[1]);
224 	if (err)
225 		return err;
226 
227 	if (drm_dp_enhanced_frame_cap(anx6345->dpcd))
228 		dpcd[1] |= DP_LANE_COUNT_ENHANCED_FRAME_EN;
229 
230 	err = drm_dp_dpcd_write(&anx6345->aux, DP_LINK_BW_SET, dpcd,
231 				sizeof(dpcd));
232 
233 	if (err < 0) {
234 		DRM_ERROR("Failed to configure link: %d\n", err);
235 		return err;
236 	}
237 
238 	/* Start training on the source */
239 	err = regmap_write(anx6345->map[I2C_IDX_DPTX], SP_DP_LT_CTRL_REG,
240 			   SP_LT_EN);
241 	if (err)
242 		return err;
243 
244 	return regmap_read_poll_timeout(anx6345->map[I2C_IDX_DPTX],
245 				       SP_DP_LT_CTRL_REG,
246 				       value, !(value & SP_DP_LT_INPROGRESS),
247 				       POLL_DELAY, POLL_TIMEOUT);
248 }
249 
250 static int anx6345_tx_initialization(struct anx6345 *anx6345)
251 {
252 	int err, i;
253 
254 	/* FIXME: colordepth is hardcoded for now */
255 	err = regmap_write(anx6345->map[I2C_IDX_TXCOM], SP_VID_CTRL2_REG,
256 			   SP_IN_BPC_6BIT << SP_IN_BPC_SHIFT);
257 	if (err)
258 		return err;
259 
260 	err = regmap_write(anx6345->map[I2C_IDX_DPTX], SP_DP_PLL_CTRL_REG, 0);
261 	if (err)
262 		return err;
263 
264 	err = regmap_write(anx6345->map[I2C_IDX_TXCOM],
265 			   SP_ANALOG_DEBUG1_REG, 0);
266 	if (err)
267 		return err;
268 
269 	err = regmap_write(anx6345->map[I2C_IDX_DPTX],
270 			   SP_DP_LINK_DEBUG_CTRL_REG,
271 			   SP_NEW_PRBS7 | SP_M_VID_DEBUG);
272 	if (err)
273 		return err;
274 
275 	err = regmap_write(anx6345->map[I2C_IDX_DPTX],
276 			   SP_DP_ANALOG_POWER_DOWN_REG, 0);
277 	if (err)
278 		return err;
279 
280 	/* Force HPD */
281 	err = anx6345_set_bits(anx6345->map[I2C_IDX_DPTX],
282 			       SP_DP_SYSTEM_CTRL_BASE + 3,
283 			       SP_HPD_FORCE | SP_HPD_CTRL);
284 	if (err)
285 		return err;
286 
287 	for (i = 0; i < 4; i++) {
288 		/* 4 lanes */
289 		err = regmap_write(anx6345->map[I2C_IDX_DPTX],
290 				   SP_DP_LANE0_LT_CTRL_REG + i, 0);
291 		if (err)
292 			return err;
293 	}
294 
295 	/* Reset AUX */
296 	err = anx6345_set_bits(anx6345->map[I2C_IDX_TXCOM],
297 			       SP_RESET_CTRL2_REG, SP_AUX_RST);
298 	if (err)
299 		return err;
300 
301 	return anx6345_clear_bits(anx6345->map[I2C_IDX_TXCOM],
302 				 SP_RESET_CTRL2_REG, SP_AUX_RST);
303 }
304 
305 static void anx6345_poweron(struct anx6345 *anx6345)
306 {
307 	int err;
308 
309 	/* Ensure reset is asserted before starting power on sequence */
310 	gpiod_set_value_cansleep(anx6345->gpiod_reset, 1);
311 	usleep_range(1000, 2000);
312 
313 	err = regulator_enable(anx6345->dvdd12);
314 	if (err) {
315 		DRM_ERROR("Failed to enable dvdd12 regulator: %d\n",
316 			  err);
317 		return;
318 	}
319 
320 	/* T1 - delay between VDD12 and VDD25 should be 0-2ms */
321 	usleep_range(1000, 2000);
322 
323 	err = regulator_enable(anx6345->dvdd25);
324 	if (err) {
325 		DRM_ERROR("Failed to enable dvdd25 regulator: %d\n",
326 			  err);
327 		return;
328 	}
329 
330 	/* T2 - delay between RESETN and all power rail stable,
331 	 * should be 2-5ms
332 	 */
333 	usleep_range(2000, 5000);
334 
335 	gpiod_set_value_cansleep(anx6345->gpiod_reset, 0);
336 
337 	/* Power on registers module */
338 	anx6345_set_bits(anx6345->map[I2C_IDX_TXCOM], SP_POWERDOWN_CTRL_REG,
339 			 SP_HDCP_PD | SP_AUDIO_PD | SP_VIDEO_PD | SP_LINK_PD);
340 	anx6345_clear_bits(anx6345->map[I2C_IDX_TXCOM], SP_POWERDOWN_CTRL_REG,
341 			   SP_REGISTER_PD | SP_TOTAL_PD);
342 
343 	if (anx6345->panel)
344 		drm_panel_prepare(anx6345->panel);
345 
346 	anx6345->powered = true;
347 }
348 
349 static void anx6345_poweroff(struct anx6345 *anx6345)
350 {
351 	int err;
352 
353 	gpiod_set_value_cansleep(anx6345->gpiod_reset, 1);
354 	usleep_range(1000, 2000);
355 
356 	if (anx6345->panel)
357 		drm_panel_unprepare(anx6345->panel);
358 
359 	err = regulator_disable(anx6345->dvdd25);
360 	if (err) {
361 		DRM_ERROR("Failed to disable dvdd25 regulator: %d\n",
362 			  err);
363 		return;
364 	}
365 
366 	usleep_range(5000, 10000);
367 
368 	err = regulator_disable(anx6345->dvdd12);
369 	if (err) {
370 		DRM_ERROR("Failed to disable dvdd12 regulator: %d\n",
371 			  err);
372 		return;
373 	}
374 
375 	usleep_range(1000, 2000);
376 
377 	anx6345->powered = false;
378 }
379 
380 static int anx6345_start(struct anx6345 *anx6345)
381 {
382 	int err;
383 
384 	if (!anx6345->powered)
385 		anx6345_poweron(anx6345);
386 
387 	/* Power on needed modules */
388 	err = anx6345_clear_bits(anx6345->map[I2C_IDX_TXCOM],
389 				SP_POWERDOWN_CTRL_REG,
390 				SP_VIDEO_PD | SP_LINK_PD);
391 
392 	err = anx6345_tx_initialization(anx6345);
393 	if (err) {
394 		DRM_ERROR("Failed eDP transmitter initialization: %d\n", err);
395 		anx6345_poweroff(anx6345);
396 		return err;
397 	}
398 
399 	err = anx6345_dp_link_training(anx6345);
400 	if (err) {
401 		DRM_ERROR("Failed link training: %d\n", err);
402 		anx6345_poweroff(anx6345);
403 		return err;
404 	}
405 
406 	/*
407 	 * This delay seems to help keep the hardware in a good state. Without
408 	 * it, there are times where it fails silently.
409 	 */
410 	usleep_range(10000, 15000);
411 
412 	return 0;
413 }
414 
415 static int anx6345_config_dp_output(struct anx6345 *anx6345)
416 {
417 	int err;
418 
419 	err = anx6345_clear_bits(anx6345->map[I2C_IDX_TXCOM], SP_VID_CTRL1_REG,
420 				 SP_VIDEO_MUTE);
421 	if (err)
422 		return err;
423 
424 	/* Enable DP output */
425 	err = anx6345_set_bits(anx6345->map[I2C_IDX_TXCOM], SP_VID_CTRL1_REG,
426 			       SP_VIDEO_EN);
427 	if (err)
428 		return err;
429 
430 	/* Force stream valid */
431 	return anx6345_set_bits(anx6345->map[I2C_IDX_DPTX],
432 			       SP_DP_SYSTEM_CTRL_BASE + 3,
433 			       SP_STRM_FORCE | SP_STRM_CTRL);
434 }
435 
436 static int anx6345_get_downstream_info(struct anx6345 *anx6345)
437 {
438 	u8 value;
439 	int err;
440 
441 	err = drm_dp_dpcd_readb(&anx6345->aux, DP_SINK_COUNT, &value);
442 	if (err < 0) {
443 		DRM_ERROR("Get sink count failed %d\n", err);
444 		return err;
445 	}
446 
447 	if (!DP_GET_SINK_COUNT(value)) {
448 		DRM_ERROR("Downstream disconnected\n");
449 		return -EIO;
450 	}
451 
452 	return 0;
453 }
454 
455 static int anx6345_get_modes(struct drm_connector *connector)
456 {
457 	struct anx6345 *anx6345 = connector_to_anx6345(connector);
458 	int err, num_modes = 0;
459 	bool power_off = false;
460 
461 	mutex_lock(&anx6345->lock);
462 
463 	if (!anx6345->edid) {
464 		if (!anx6345->powered) {
465 			anx6345_poweron(anx6345);
466 			power_off = true;
467 		}
468 
469 		err = anx6345_get_downstream_info(anx6345);
470 		if (err) {
471 			DRM_ERROR("Failed to get downstream info: %d\n", err);
472 			goto unlock;
473 		}
474 
475 		anx6345->edid = drm_get_edid(connector, &anx6345->aux.ddc);
476 		if (!anx6345->edid)
477 			DRM_ERROR("Failed to read EDID from panel\n");
478 
479 		err = drm_connector_update_edid_property(connector,
480 							 anx6345->edid);
481 		if (err) {
482 			DRM_ERROR("Failed to update EDID property: %d\n", err);
483 			goto unlock;
484 		}
485 	}
486 
487 	num_modes += drm_add_edid_modes(connector, anx6345->edid);
488 
489 unlock:
490 	if (power_off)
491 		anx6345_poweroff(anx6345);
492 
493 	mutex_unlock(&anx6345->lock);
494 
495 	if (!num_modes && anx6345->panel)
496 		num_modes += drm_panel_get_modes(anx6345->panel, connector);
497 
498 	return num_modes;
499 }
500 
501 static const struct drm_connector_helper_funcs anx6345_connector_helper_funcs = {
502 	.get_modes = anx6345_get_modes,
503 };
504 
505 static void
506 anx6345_connector_destroy(struct drm_connector *connector)
507 {
508 	struct anx6345 *anx6345 = connector_to_anx6345(connector);
509 
510 	if (anx6345->panel)
511 		drm_panel_detach(anx6345->panel);
512 	drm_connector_cleanup(connector);
513 }
514 
515 static const struct drm_connector_funcs anx6345_connector_funcs = {
516 	.fill_modes = drm_helper_probe_single_connector_modes,
517 	.destroy = anx6345_connector_destroy,
518 	.reset = drm_atomic_helper_connector_reset,
519 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
520 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
521 };
522 
523 static int anx6345_bridge_attach(struct drm_bridge *bridge)
524 {
525 	struct anx6345 *anx6345 = bridge_to_anx6345(bridge);
526 	int err;
527 
528 	if (!bridge->encoder) {
529 		DRM_ERROR("Parent encoder object not found");
530 		return -ENODEV;
531 	}
532 
533 	/* Register aux channel */
534 	anx6345->aux.name = "DP-AUX";
535 	anx6345->aux.dev = &anx6345->client->dev;
536 	anx6345->aux.transfer = anx6345_aux_transfer;
537 
538 	err = drm_dp_aux_register(&anx6345->aux);
539 	if (err < 0) {
540 		DRM_ERROR("Failed to register aux channel: %d\n", err);
541 		return err;
542 	}
543 
544 	err = drm_connector_init(bridge->dev, &anx6345->connector,
545 				 &anx6345_connector_funcs,
546 				 DRM_MODE_CONNECTOR_eDP);
547 	if (err) {
548 		DRM_ERROR("Failed to initialize connector: %d\n", err);
549 		return err;
550 	}
551 
552 	drm_connector_helper_add(&anx6345->connector,
553 				 &anx6345_connector_helper_funcs);
554 
555 	err = drm_connector_register(&anx6345->connector);
556 	if (err) {
557 		DRM_ERROR("Failed to register connector: %d\n", err);
558 		return err;
559 	}
560 
561 	anx6345->connector.polled = DRM_CONNECTOR_POLL_HPD;
562 
563 	err = drm_connector_attach_encoder(&anx6345->connector,
564 					   bridge->encoder);
565 	if (err) {
566 		DRM_ERROR("Failed to link up connector to encoder: %d\n", err);
567 		return err;
568 	}
569 
570 	if (anx6345->panel) {
571 		err = drm_panel_attach(anx6345->panel, &anx6345->connector);
572 		if (err) {
573 			DRM_ERROR("Failed to attach panel: %d\n", err);
574 			return err;
575 		}
576 	}
577 
578 	return 0;
579 }
580 
581 static enum drm_mode_status
582 anx6345_bridge_mode_valid(struct drm_bridge *bridge,
583 			  const struct drm_display_mode *mode)
584 {
585 	if (mode->flags & DRM_MODE_FLAG_INTERLACE)
586 		return MODE_NO_INTERLACE;
587 
588 	/* Max 1200p at 5.4 Ghz, one lane */
589 	if (mode->clock > 154000)
590 		return MODE_CLOCK_HIGH;
591 
592 	return MODE_OK;
593 }
594 
595 static void anx6345_bridge_disable(struct drm_bridge *bridge)
596 {
597 	struct anx6345 *anx6345 = bridge_to_anx6345(bridge);
598 
599 	/* Power off all modules except configuration registers access */
600 	anx6345_set_bits(anx6345->map[I2C_IDX_TXCOM], SP_POWERDOWN_CTRL_REG,
601 			 SP_HDCP_PD | SP_AUDIO_PD | SP_VIDEO_PD | SP_LINK_PD);
602 	if (anx6345->panel)
603 		drm_panel_disable(anx6345->panel);
604 
605 	if (anx6345->powered)
606 		anx6345_poweroff(anx6345);
607 }
608 
609 static void anx6345_bridge_enable(struct drm_bridge *bridge)
610 {
611 	struct anx6345 *anx6345 = bridge_to_anx6345(bridge);
612 	int err;
613 
614 	if (anx6345->panel)
615 		drm_panel_enable(anx6345->panel);
616 
617 	err = anx6345_start(anx6345);
618 	if (err) {
619 		DRM_ERROR("Failed to initialize: %d\n", err);
620 		return;
621 	}
622 
623 	err = anx6345_config_dp_output(anx6345);
624 	if (err)
625 		DRM_ERROR("Failed to enable DP output: %d\n", err);
626 }
627 
628 static const struct drm_bridge_funcs anx6345_bridge_funcs = {
629 	.attach = anx6345_bridge_attach,
630 	.mode_valid = anx6345_bridge_mode_valid,
631 	.disable = anx6345_bridge_disable,
632 	.enable = anx6345_bridge_enable,
633 };
634 
635 static void unregister_i2c_dummy_clients(struct anx6345 *anx6345)
636 {
637 	unsigned int i;
638 
639 	for (i = 1; i < ARRAY_SIZE(anx6345->i2c_clients); i++)
640 		if (anx6345->i2c_clients[i] &&
641 		    anx6345->i2c_clients[i]->addr != anx6345->client->addr)
642 			i2c_unregister_device(anx6345->i2c_clients[i]);
643 }
644 
645 static const struct regmap_config anx6345_regmap_config = {
646 	.reg_bits = 8,
647 	.val_bits = 8,
648 	.max_register = 0xff,
649 	.cache_type = REGCACHE_NONE,
650 };
651 
652 static const u16 anx6345_chipid_list[] = {
653 	0x6345,
654 };
655 
656 static bool anx6345_get_chip_id(struct anx6345 *anx6345)
657 {
658 	unsigned int i, idl, idh, version;
659 
660 	if (regmap_read(anx6345->map[I2C_IDX_TXCOM], SP_DEVICE_IDL_REG, &idl))
661 		return false;
662 
663 	if (regmap_read(anx6345->map[I2C_IDX_TXCOM], SP_DEVICE_IDH_REG, &idh))
664 		return false;
665 
666 	anx6345->chipid = (u8)idl | ((u8)idh << 8);
667 
668 	if (regmap_read(anx6345->map[I2C_IDX_TXCOM], SP_DEVICE_VERSION_REG,
669 			&version))
670 		return false;
671 
672 	for (i = 0; i < ARRAY_SIZE(anx6345_chipid_list); i++) {
673 		if (anx6345->chipid == anx6345_chipid_list[i]) {
674 			DRM_INFO("Found ANX%x (ver. %d) eDP Transmitter\n",
675 				 anx6345->chipid, version);
676 			return true;
677 		}
678 	}
679 
680 	DRM_ERROR("ANX%x (ver. %d) not supported by this driver\n",
681 		  anx6345->chipid, version);
682 
683 	return false;
684 }
685 
686 static int anx6345_i2c_probe(struct i2c_client *client,
687 			     const struct i2c_device_id *id)
688 {
689 	struct anx6345 *anx6345;
690 	struct device *dev;
691 	int i, err;
692 
693 	anx6345 = devm_kzalloc(&client->dev, sizeof(*anx6345), GFP_KERNEL);
694 	if (!anx6345)
695 		return -ENOMEM;
696 
697 	mutex_init(&anx6345->lock);
698 
699 	anx6345->bridge.of_node = client->dev.of_node;
700 
701 	anx6345->client = client;
702 	i2c_set_clientdata(client, anx6345);
703 
704 	dev = &anx6345->client->dev;
705 
706 	err = drm_of_find_panel_or_bridge(client->dev.of_node, 1, 0,
707 					  &anx6345->panel, NULL);
708 	if (err == -EPROBE_DEFER)
709 		return err;
710 
711 	if (err)
712 		DRM_DEBUG("No panel found\n");
713 
714 	/* 1.2V digital core power regulator  */
715 	anx6345->dvdd12 = devm_regulator_get(dev, "dvdd12-supply");
716 	if (IS_ERR(anx6345->dvdd12)) {
717 		DRM_ERROR("dvdd12-supply not found\n");
718 		return PTR_ERR(anx6345->dvdd12);
719 	}
720 
721 	/* 2.5V digital core power regulator  */
722 	anx6345->dvdd25 = devm_regulator_get(dev, "dvdd25-supply");
723 	if (IS_ERR(anx6345->dvdd25)) {
724 		DRM_ERROR("dvdd25-supply not found\n");
725 		return PTR_ERR(anx6345->dvdd25);
726 	}
727 
728 	/* GPIO for chip reset */
729 	anx6345->gpiod_reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW);
730 	if (IS_ERR(anx6345->gpiod_reset)) {
731 		DRM_ERROR("Reset gpio not found\n");
732 		return PTR_ERR(anx6345->gpiod_reset);
733 	}
734 
735 	/* Map slave addresses of ANX6345 */
736 	for (i = 0; i < I2C_NUM_ADDRESSES; i++) {
737 		if (anx6345_i2c_addresses[i] >> 1 != client->addr)
738 			anx6345->i2c_clients[i] = i2c_new_dummy_device(client->adapter,
739 						anx6345_i2c_addresses[i] >> 1);
740 		else
741 			anx6345->i2c_clients[i] = client;
742 
743 		if (IS_ERR(anx6345->i2c_clients[i])) {
744 			err = PTR_ERR(anx6345->i2c_clients[i]);
745 			DRM_ERROR("Failed to reserve I2C bus %02x\n",
746 				  anx6345_i2c_addresses[i]);
747 			goto err_unregister_i2c;
748 		}
749 
750 		anx6345->map[i] = devm_regmap_init_i2c(anx6345->i2c_clients[i],
751 						       &anx6345_regmap_config);
752 		if (IS_ERR(anx6345->map[i])) {
753 			err = PTR_ERR(anx6345->map[i]);
754 			DRM_ERROR("Failed regmap initialization %02x\n",
755 				  anx6345_i2c_addresses[i]);
756 			goto err_unregister_i2c;
757 		}
758 	}
759 
760 	/* Look for supported chip ID */
761 	anx6345_poweron(anx6345);
762 	if (anx6345_get_chip_id(anx6345)) {
763 		anx6345->bridge.funcs = &anx6345_bridge_funcs;
764 		drm_bridge_add(&anx6345->bridge);
765 
766 		return 0;
767 	} else {
768 		anx6345_poweroff(anx6345);
769 		err = -ENODEV;
770 	}
771 
772 err_unregister_i2c:
773 	unregister_i2c_dummy_clients(anx6345);
774 	return err;
775 }
776 
777 static int anx6345_i2c_remove(struct i2c_client *client)
778 {
779 	struct anx6345 *anx6345 = i2c_get_clientdata(client);
780 
781 	drm_bridge_remove(&anx6345->bridge);
782 
783 	unregister_i2c_dummy_clients(anx6345);
784 
785 	kfree(anx6345->edid);
786 
787 	mutex_destroy(&anx6345->lock);
788 
789 	return 0;
790 }
791 
792 static const struct i2c_device_id anx6345_id[] = {
793 	{ "anx6345", 0 },
794 	{ /* sentinel */ }
795 };
796 MODULE_DEVICE_TABLE(i2c, anx6345_id);
797 
798 static const struct of_device_id anx6345_match_table[] = {
799 	{ .compatible = "analogix,anx6345", },
800 	{ /* sentinel */ },
801 };
802 MODULE_DEVICE_TABLE(of, anx6345_match_table);
803 
804 static struct i2c_driver anx6345_driver = {
805 	.driver = {
806 		   .name = "anx6345",
807 		   .of_match_table = of_match_ptr(anx6345_match_table),
808 		  },
809 	.probe = anx6345_i2c_probe,
810 	.remove = anx6345_i2c_remove,
811 	.id_table = anx6345_id,
812 };
813 module_i2c_driver(anx6345_driver);
814 
815 MODULE_DESCRIPTION("ANX6345 eDP Transmitter driver");
816 MODULE_AUTHOR("Icenowy Zheng <icenowy@aosc.io>");
817 MODULE_LICENSE("GPL v2");
818