1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Chrontel CH7033 Video Encoder Driver
4 *
5 * Copyright (C) 2019,2020 Lubomir Rintel
6 */
7
8#include <linux/gpio/consumer.h>
9#include <linux/i2c.h>
10#include <linux/module.h>
11#include <linux/regmap.h>
12
13#include <drm/drm_atomic_helper.h>
14#include <drm/drm_bridge.h>
15#include <drm/drm_edid.h>
16#include <drm/drm_of.h>
17#include <drm/drm_print.h>
18#include <drm/drm_probe_helper.h>
19
20/* Page 0, Register 0x07 */
21enum {
22	DRI_PD		= BIT(3),
23	IO_PD		= BIT(5),
24};
25
26/* Page 0, Register 0x08 */
27enum {
28	DRI_PDDRI	= GENMASK(7, 4),
29	PDDAC		= GENMASK(3, 1),
30	PANEN		= BIT(0),
31};
32
33/* Page 0, Register 0x09 */
34enum {
35	DPD		= BIT(7),
36	GCKOFF		= BIT(6),
37	TV_BP		= BIT(5),
38	SCLPD		= BIT(4),
39	SDPD		= BIT(3),
40	VGA_PD		= BIT(2),
41	HDBKPD		= BIT(1),
42	HDMI_PD		= BIT(0),
43};
44
45/* Page 0, Register 0x0a */
46enum {
47	MEMINIT		= BIT(7),
48	MEMIDLE		= BIT(6),
49	MEMPD		= BIT(5),
50	STOP		= BIT(4),
51	LVDS_PD		= BIT(3),
52	HD_DVIB		= BIT(2),
53	HDCP_PD		= BIT(1),
54	MCU_PD		= BIT(0),
55};
56
57/* Page 0, Register 0x18 */
58enum {
59	IDF		= GENMASK(7, 4),
60	INTEN		= BIT(3),
61	SWAP		= GENMASK(2, 0),
62};
63
64enum {
65	BYTE_SWAP_RGB	= 0,
66	BYTE_SWAP_RBG	= 1,
67	BYTE_SWAP_GRB	= 2,
68	BYTE_SWAP_GBR	= 3,
69	BYTE_SWAP_BRG	= 4,
70	BYTE_SWAP_BGR	= 5,
71};
72
73/* Page 0, Register 0x19 */
74enum {
75	HPO_I		= BIT(5),
76	VPO_I		= BIT(4),
77	DEPO_I		= BIT(3),
78	CRYS_EN		= BIT(2),
79	GCLKFREQ	= GENMASK(2, 0),
80};
81
82/* Page 0, Register 0x2e */
83enum {
84	HFLIP		= BIT(7),
85	VFLIP		= BIT(6),
86	DEPO_O		= BIT(5),
87	HPO_O		= BIT(4),
88	VPO_O		= BIT(3),
89	TE		= GENMASK(2, 0),
90};
91
92/* Page 0, Register 0x2b */
93enum {
94	SWAPS		= GENMASK(7, 4),
95	VFMT		= GENMASK(3, 0),
96};
97
98/* Page 0, Register 0x54 */
99enum {
100	COMP_BP		= BIT(7),
101	DAC_EN_T	= BIT(6),
102	HWO_HDMI_HI	= GENMASK(5, 3),
103	HOO_HDMI_HI	= GENMASK(2, 0),
104};
105
106/* Page 0, Register 0x57 */
107enum {
108	FLDSEN		= BIT(7),
109	VWO_HDMI_HI	= GENMASK(5, 3),
110	VOO_HDMI_HI	= GENMASK(2, 0),
111};
112
113/* Page 0, Register 0x7e */
114enum {
115	HDMI_LVDS_SEL	= BIT(7),
116	DE_GEN		= BIT(6),
117	PWM_INDEX_HI	= BIT(5),
118	USE_DE		= BIT(4),
119	R_INT		= GENMASK(3, 0),
120};
121
122/* Page 1, Register 0x07 */
123enum {
124	BPCKSEL		= BIT(7),
125	DRI_CMFB_EN	= BIT(6),
126	CEC_PUEN	= BIT(5),
127	CEC_T		= BIT(3),
128	CKINV		= BIT(2),
129	CK_TVINV	= BIT(1),
130	DRI_CKS2	= BIT(0),
131};
132
133/* Page 1, Register 0x08 */
134enum {
135	DACG		= BIT(6),
136	DACKTST		= BIT(5),
137	DEDGEB		= BIT(4),
138	SYO		= BIT(3),
139	DRI_IT_LVDS	= GENMASK(2, 1),
140	DISPON		= BIT(0),
141};
142
143/* Page 1, Register 0x0c */
144enum {
145	DRI_PLL_CP	= GENMASK(7, 6),
146	DRI_PLL_DIVSEL	= BIT(5),
147	DRI_PLL_N1_1	= BIT(4),
148	DRI_PLL_N1_0	= BIT(3),
149	DRI_PLL_N3_1	= BIT(2),
150	DRI_PLL_N3_0	= BIT(1),
151	DRI_PLL_CKTSTEN = BIT(0),
152};
153
154/* Page 1, Register 0x6b */
155enum {
156	VCO3CS		= GENMASK(7, 6),
157	ICPGBK2_0	= GENMASK(5, 3),
158	DRI_VCO357SC	= BIT(2),
159	PDPLL2		= BIT(1),
160	DRI_PD_SER	= BIT(0),
161};
162
163/* Page 1, Register 0x6c */
164enum {
165	PLL2N11		= GENMASK(7, 4),
166	PLL2N5_4	= BIT(3),
167	PLL2N5_TOP	= BIT(2),
168	DRI_PLL_PD	= BIT(1),
169	PD_I2CM		= BIT(0),
170};
171
172/* Page 3, Register 0x28 */
173enum {
174	DIFF_EN		= GENMASK(7, 6),
175	CORREC_EN	= GENMASK(5, 4),
176	VGACLK_BP	= BIT(3),
177	HM_LV_SEL	= BIT(2),
178	HD_VGA_SEL	= BIT(1),
179};
180
181/* Page 3, Register 0x2a */
182enum {
183	LVDSCLK_BP	= BIT(7),
184	HDTVCLK_BP	= BIT(6),
185	HDMICLK_BP	= BIT(5),
186	HDTV_BP		= BIT(4),
187	HDMI_BP		= BIT(3),
188	THRWL		= GENMASK(2, 0),
189};
190
191/* Page 4, Register 0x52 */
192enum {
193	PGM_ARSTB	= BIT(7),
194	MCU_ARSTB	= BIT(6),
195	MCU_RETB	= BIT(2),
196	RESETIB		= BIT(1),
197	RESETDB		= BIT(0),
198};
199
200struct ch7033_priv {
201	struct regmap *regmap;
202	struct drm_bridge *next_bridge;
203	struct drm_bridge bridge;
204	struct drm_connector connector;
205};
206
207#define conn_to_ch7033_priv(x) \
208	container_of(x, struct ch7033_priv, connector)
209#define bridge_to_ch7033_priv(x) \
210	container_of(x, struct ch7033_priv, bridge)
211
212
213static enum drm_connector_status ch7033_connector_detect(
214	struct drm_connector *connector, bool force)
215{
216	struct ch7033_priv *priv = conn_to_ch7033_priv(connector);
217
218	return drm_bridge_detect(priv->next_bridge);
219}
220
221static const struct drm_connector_funcs ch7033_connector_funcs = {
222	.reset = drm_atomic_helper_connector_reset,
223	.fill_modes = drm_helper_probe_single_connector_modes,
224	.detect = ch7033_connector_detect,
225	.destroy = drm_connector_cleanup,
226	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
227	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
228};
229
230static int ch7033_connector_get_modes(struct drm_connector *connector)
231{
232	struct ch7033_priv *priv = conn_to_ch7033_priv(connector);
233	const struct drm_edid *drm_edid;
234	int ret;
235
236	drm_edid = drm_bridge_edid_read(priv->next_bridge, connector);
237	drm_edid_connector_update(connector, drm_edid);
238	if (drm_edid) {
239		ret = drm_edid_connector_add_modes(connector);
240		drm_edid_free(drm_edid);
241	} else {
242		ret = drm_add_modes_noedid(connector, 1920, 1080);
243		drm_set_preferred_mode(connector, 1024, 768);
244	}
245
246	return ret;
247}
248
249static struct drm_encoder *ch7033_connector_best_encoder(
250			struct drm_connector *connector)
251{
252	struct ch7033_priv *priv = conn_to_ch7033_priv(connector);
253
254	return priv->bridge.encoder;
255}
256
257static const struct drm_connector_helper_funcs ch7033_connector_helper_funcs = {
258	.get_modes = ch7033_connector_get_modes,
259	.best_encoder = ch7033_connector_best_encoder,
260};
261
262static void ch7033_hpd_event(void *arg, enum drm_connector_status status)
263{
264	struct ch7033_priv *priv = arg;
265
266	if (priv->bridge.dev)
267		drm_helper_hpd_irq_event(priv->connector.dev);
268}
269
270static int ch7033_bridge_attach(struct drm_bridge *bridge,
271				enum drm_bridge_attach_flags flags)
272{
273	struct ch7033_priv *priv = bridge_to_ch7033_priv(bridge);
274	struct drm_connector *connector = &priv->connector;
275	int ret;
276
277	ret = drm_bridge_attach(bridge->encoder, priv->next_bridge, bridge,
278				DRM_BRIDGE_ATTACH_NO_CONNECTOR);
279	if (ret)
280		return ret;
281
282	if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR)
283		return 0;
284
285	if (priv->next_bridge->ops & DRM_BRIDGE_OP_DETECT) {
286		connector->polled = DRM_CONNECTOR_POLL_HPD;
287	} else {
288		connector->polled = DRM_CONNECTOR_POLL_CONNECT |
289				    DRM_CONNECTOR_POLL_DISCONNECT;
290	}
291
292	if (priv->next_bridge->ops & DRM_BRIDGE_OP_HPD) {
293		drm_bridge_hpd_enable(priv->next_bridge, ch7033_hpd_event,
294				      priv);
295	}
296
297	drm_connector_helper_add(connector,
298				 &ch7033_connector_helper_funcs);
299	ret = drm_connector_init_with_ddc(bridge->dev, &priv->connector,
300					  &ch7033_connector_funcs,
301					  priv->next_bridge->type,
302					  priv->next_bridge->ddc);
303	if (ret) {
304		DRM_ERROR("Failed to initialize connector\n");
305		return ret;
306	}
307
308	return drm_connector_attach_encoder(&priv->connector, bridge->encoder);
309}
310
311static void ch7033_bridge_detach(struct drm_bridge *bridge)
312{
313	struct ch7033_priv *priv = bridge_to_ch7033_priv(bridge);
314
315	if (priv->next_bridge->ops & DRM_BRIDGE_OP_HPD)
316		drm_bridge_hpd_disable(priv->next_bridge);
317	drm_connector_cleanup(&priv->connector);
318}
319
320static enum drm_mode_status ch7033_bridge_mode_valid(struct drm_bridge *bridge,
321				     const struct drm_display_info *info,
322				     const struct drm_display_mode *mode)
323{
324	if (mode->clock > 165000)
325		return MODE_CLOCK_HIGH;
326	if (mode->hdisplay >= 1920)
327		return MODE_BAD_HVALUE;
328	if (mode->vdisplay >= 1080)
329		return MODE_BAD_VVALUE;
330	return MODE_OK;
331}
332
333static void ch7033_bridge_disable(struct drm_bridge *bridge)
334{
335	struct ch7033_priv *priv = bridge_to_ch7033_priv(bridge);
336
337	regmap_write(priv->regmap, 0x03, 0x04);
338	regmap_update_bits(priv->regmap, 0x52, RESETDB, 0x00);
339}
340
341static void ch7033_bridge_enable(struct drm_bridge *bridge)
342{
343	struct ch7033_priv *priv = bridge_to_ch7033_priv(bridge);
344
345	regmap_write(priv->regmap, 0x03, 0x04);
346	regmap_update_bits(priv->regmap, 0x52, RESETDB, RESETDB);
347}
348
349static void ch7033_bridge_mode_set(struct drm_bridge *bridge,
350				   const struct drm_display_mode *mode,
351				   const struct drm_display_mode *adjusted_mode)
352{
353	struct ch7033_priv *priv = bridge_to_ch7033_priv(bridge);
354	int hbporch = mode->hsync_start - mode->hdisplay;
355	int hsynclen = mode->hsync_end - mode->hsync_start;
356	int vbporch = mode->vsync_start - mode->vdisplay;
357	int vsynclen = mode->vsync_end - mode->vsync_start;
358
359	/*
360	 * Page 4
361	 */
362	regmap_write(priv->regmap, 0x03, 0x04);
363
364	/* Turn everything off to set all the registers to their defaults. */
365	regmap_write(priv->regmap, 0x52, 0x00);
366	/* Bring I/O block up. */
367	regmap_write(priv->regmap, 0x52, RESETIB);
368
369	/*
370	 * Page 0
371	 */
372	regmap_write(priv->regmap, 0x03, 0x00);
373
374	/* Bring up parts we need from the power down. */
375	regmap_update_bits(priv->regmap, 0x07, DRI_PD | IO_PD, 0);
376	regmap_update_bits(priv->regmap, 0x08, DRI_PDDRI | PDDAC | PANEN, 0);
377	regmap_update_bits(priv->regmap, 0x09, DPD | GCKOFF |
378					       HDMI_PD | VGA_PD, 0);
379	regmap_update_bits(priv->regmap, 0x0a, HD_DVIB, 0);
380
381	/* Horizontal input timing. */
382	regmap_write(priv->regmap, 0x0b, (mode->htotal >> 8) << 3 |
383					 (mode->hdisplay >> 8));
384	regmap_write(priv->regmap, 0x0c, mode->hdisplay);
385	regmap_write(priv->regmap, 0x0d, mode->htotal);
386	regmap_write(priv->regmap, 0x0e, (hsynclen >> 8) << 3 |
387					 (hbporch >> 8));
388	regmap_write(priv->regmap, 0x0f, hbporch);
389	regmap_write(priv->regmap, 0x10, hsynclen);
390
391	/* Vertical input timing. */
392	regmap_write(priv->regmap, 0x11, (mode->vtotal >> 8) << 3 |
393					 (mode->vdisplay >> 8));
394	regmap_write(priv->regmap, 0x12, mode->vdisplay);
395	regmap_write(priv->regmap, 0x13, mode->vtotal);
396	regmap_write(priv->regmap, 0x14, ((vsynclen >> 8) << 3) |
397					 (vbporch >> 8));
398	regmap_write(priv->regmap, 0x15, vbporch);
399	regmap_write(priv->regmap, 0x16, vsynclen);
400
401	/* Input color swap. */
402	regmap_update_bits(priv->regmap, 0x18, SWAP, BYTE_SWAP_BGR);
403
404	/* Input clock and sync polarity. */
405	regmap_update_bits(priv->regmap, 0x19, 0x1, mode->clock >> 16);
406	regmap_update_bits(priv->regmap, 0x19, HPO_I | VPO_I | GCLKFREQ,
407			   (mode->flags & DRM_MODE_FLAG_PHSYNC) ? HPO_I : 0 |
408			   (mode->flags & DRM_MODE_FLAG_PVSYNC) ? VPO_I : 0 |
409			   mode->clock >> 16);
410	regmap_write(priv->regmap, 0x1a, mode->clock >> 8);
411	regmap_write(priv->regmap, 0x1b, mode->clock);
412
413	/* Horizontal output timing. */
414	regmap_write(priv->regmap, 0x1f, (mode->htotal >> 8) << 3 |
415					 (mode->hdisplay >> 8));
416	regmap_write(priv->regmap, 0x20, mode->hdisplay);
417	regmap_write(priv->regmap, 0x21, mode->htotal);
418
419	/* Vertical output timing. */
420	regmap_write(priv->regmap, 0x25, (mode->vtotal >> 8) << 3 |
421					 (mode->vdisplay >> 8));
422	regmap_write(priv->regmap, 0x26, mode->vdisplay);
423	regmap_write(priv->regmap, 0x27, mode->vtotal);
424
425	/* VGA channel bypass */
426	regmap_update_bits(priv->regmap, 0x2b, VFMT, 9);
427
428	/* Output sync polarity. */
429	regmap_update_bits(priv->regmap, 0x2e, HPO_O | VPO_O,
430			   (mode->flags & DRM_MODE_FLAG_PHSYNC) ? HPO_O : 0 |
431			   (mode->flags & DRM_MODE_FLAG_PVSYNC) ? VPO_O : 0);
432
433	/* HDMI horizontal output timing. */
434	regmap_update_bits(priv->regmap, 0x54, HWO_HDMI_HI | HOO_HDMI_HI,
435					       (hsynclen >> 8) << 3 |
436					       (hbporch >> 8));
437	regmap_write(priv->regmap, 0x55, hbporch);
438	regmap_write(priv->regmap, 0x56, hsynclen);
439
440	/* HDMI vertical output timing. */
441	regmap_update_bits(priv->regmap, 0x57, VWO_HDMI_HI | VOO_HDMI_HI,
442					       (vsynclen >> 8) << 3 |
443					       (vbporch >> 8));
444	regmap_write(priv->regmap, 0x58, vbporch);
445	regmap_write(priv->regmap, 0x59, vsynclen);
446
447	/* Pick HDMI, not LVDS. */
448	regmap_update_bits(priv->regmap, 0x7e, HDMI_LVDS_SEL, HDMI_LVDS_SEL);
449
450	/*
451	 * Page 1
452	 */
453	regmap_write(priv->regmap, 0x03, 0x01);
454
455	/* No idea what these do, but VGA is wobbly and blinky without them. */
456	regmap_update_bits(priv->regmap, 0x07, CKINV, CKINV);
457	regmap_update_bits(priv->regmap, 0x08, DISPON, DISPON);
458
459	/* DRI PLL */
460	regmap_update_bits(priv->regmap, 0x0c, DRI_PLL_DIVSEL, DRI_PLL_DIVSEL);
461	if (mode->clock <= 40000) {
462		regmap_update_bits(priv->regmap, 0x0c, DRI_PLL_N1_1 |
463						       DRI_PLL_N1_0 |
464						       DRI_PLL_N3_1 |
465						       DRI_PLL_N3_0,
466						       0);
467	} else if (mode->clock < 80000) {
468		regmap_update_bits(priv->regmap, 0x0c, DRI_PLL_N1_1 |
469						       DRI_PLL_N1_0 |
470						       DRI_PLL_N3_1 |
471						       DRI_PLL_N3_0,
472						       DRI_PLL_N3_0 |
473						       DRI_PLL_N1_0);
474	} else {
475		regmap_update_bits(priv->regmap, 0x0c, DRI_PLL_N1_1 |
476						       DRI_PLL_N1_0 |
477						       DRI_PLL_N3_1 |
478						       DRI_PLL_N3_0,
479						       DRI_PLL_N3_1 |
480						       DRI_PLL_N1_1);
481	}
482
483	/* This seems to be color calibration for VGA. */
484	regmap_write(priv->regmap, 0x64, 0x29); /* LSB Blue */
485	regmap_write(priv->regmap, 0x65, 0x29); /* LSB Green */
486	regmap_write(priv->regmap, 0x66, 0x29); /* LSB Red */
487	regmap_write(priv->regmap, 0x67, 0x00); /* MSB Blue */
488	regmap_write(priv->regmap, 0x68, 0x00); /* MSB Green */
489	regmap_write(priv->regmap, 0x69, 0x00); /* MSB Red */
490
491	regmap_update_bits(priv->regmap, 0x6b, DRI_PD_SER, 0x00);
492	regmap_update_bits(priv->regmap, 0x6c, DRI_PLL_PD, 0x00);
493
494	/*
495	 * Page 3
496	 */
497	regmap_write(priv->regmap, 0x03, 0x03);
498
499	/* More bypasses and apparently another HDMI/LVDS selector. */
500	regmap_update_bits(priv->regmap, 0x28, VGACLK_BP | HM_LV_SEL,
501					       VGACLK_BP | HM_LV_SEL);
502	regmap_update_bits(priv->regmap, 0x2a, HDMICLK_BP | HDMI_BP,
503					       HDMICLK_BP | HDMI_BP);
504
505	/*
506	 * Page 4
507	 */
508	regmap_write(priv->regmap, 0x03, 0x04);
509
510	/* Output clock. */
511	regmap_write(priv->regmap, 0x10, mode->clock >> 16);
512	regmap_write(priv->regmap, 0x11, mode->clock >> 8);
513	regmap_write(priv->regmap, 0x12, mode->clock);
514}
515
516static const struct drm_bridge_funcs ch7033_bridge_funcs = {
517	.attach = ch7033_bridge_attach,
518	.detach = ch7033_bridge_detach,
519	.mode_valid = ch7033_bridge_mode_valid,
520	.disable = ch7033_bridge_disable,
521	.enable = ch7033_bridge_enable,
522	.mode_set = ch7033_bridge_mode_set,
523};
524
525static const struct regmap_config ch7033_regmap_config = {
526	.reg_bits = 8,
527	.val_bits = 8,
528	.max_register = 0x7f,
529};
530
531static int ch7033_probe(struct i2c_client *client)
532{
533	struct device *dev = &client->dev;
534	struct ch7033_priv *priv;
535	unsigned int val;
536	int ret;
537
538	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
539	if (!priv)
540		return -ENOMEM;
541
542	dev_set_drvdata(dev, priv);
543
544	ret = drm_of_find_panel_or_bridge(dev->of_node, 1, -1, NULL,
545					  &priv->next_bridge);
546	if (ret)
547		return ret;
548
549	priv->regmap = devm_regmap_init_i2c(client, &ch7033_regmap_config);
550	if (IS_ERR(priv->regmap)) {
551		dev_err(&client->dev, "regmap init failed\n");
552		return PTR_ERR(priv->regmap);
553	}
554
555	ret = regmap_read(priv->regmap, 0x00, &val);
556	if (ret < 0) {
557		dev_err(&client->dev, "error reading the model id: %d\n", ret);
558		return ret;
559	}
560	if ((val & 0xf7) != 0x56) {
561		dev_err(&client->dev, "the device is not a ch7033\n");
562		return -ENODEV;
563	}
564
565	regmap_write(priv->regmap, 0x03, 0x04);
566	ret = regmap_read(priv->regmap, 0x51, &val);
567	if (ret < 0) {
568		dev_err(&client->dev, "error reading the model id: %d\n", ret);
569		return ret;
570	}
571	if ((val & 0x0f) != 3) {
572		dev_err(&client->dev, "unknown revision %u\n", val);
573		return -ENODEV;
574	}
575
576	INIT_LIST_HEAD(&priv->bridge.list);
577	priv->bridge.funcs = &ch7033_bridge_funcs;
578	priv->bridge.of_node = dev->of_node;
579	drm_bridge_add(&priv->bridge);
580
581	dev_info(dev, "Chrontel CH7033 Video Encoder\n");
582	return 0;
583}
584
585static void ch7033_remove(struct i2c_client *client)
586{
587	struct device *dev = &client->dev;
588	struct ch7033_priv *priv = dev_get_drvdata(dev);
589
590	drm_bridge_remove(&priv->bridge);
591}
592
593static const struct of_device_id ch7033_dt_ids[] = {
594	{ .compatible = "chrontel,ch7033", },
595	{ }
596};
597MODULE_DEVICE_TABLE(of, ch7033_dt_ids);
598
599static const struct i2c_device_id ch7033_ids[] = {
600	{ "ch7033", 0 },
601	{ }
602};
603MODULE_DEVICE_TABLE(i2c, ch7033_ids);
604
605static struct i2c_driver ch7033_driver = {
606	.probe = ch7033_probe,
607	.remove = ch7033_remove,
608	.driver = {
609		.name = "ch7033",
610		.of_match_table = ch7033_dt_ids,
611	},
612	.id_table = ch7033_ids,
613};
614
615module_i2c_driver(ch7033_driver);
616
617MODULE_AUTHOR("Lubomir Rintel <lkundrak@v3.sk>");
618MODULE_DESCRIPTION("Chrontel CH7033 Video Encoder Driver");
619MODULE_LICENSE("GPL v2");
620