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 */
21 enum {
22 	DRI_PD		= BIT(3),
23 	IO_PD		= BIT(5),
24 };
25 
26 /* Page 0, Register 0x08 */
27 enum {
28 	DRI_PDDRI	= GENMASK(7, 4),
29 	PDDAC		= GENMASK(3, 1),
30 	PANEN		= BIT(0),
31 };
32 
33 /* Page 0, Register 0x09 */
34 enum {
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 */
46 enum {
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 */
58 enum {
59 	IDF		= GENMASK(7, 4),
60 	INTEN		= BIT(3),
61 	SWAP		= GENMASK(2, 0),
62 };
63 
64 enum {
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 */
74 enum {
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 */
83 enum {
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 */
93 enum {
94 	SWAPS		= GENMASK(7, 4),
95 	VFMT		= GENMASK(3, 0),
96 };
97 
98 /* Page 0, Register 0x54 */
99 enum {
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 */
107 enum {
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 */
114 enum {
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 */
123 enum {
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 */
134 enum {
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 */
144 enum {
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 */
155 enum {
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 */
164 enum {
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 */
173 enum {
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 */
182 enum {
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 */
192 enum {
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 
200 struct 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 
ch7033_connector_detect(struct drm_connector * connector,bool force)213 static 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 
221 static 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 
ch7033_connector_get_modes(struct drm_connector * connector)230 static int ch7033_connector_get_modes(struct drm_connector *connector)
231 {
232 	struct ch7033_priv *priv = conn_to_ch7033_priv(connector);
233 	struct edid *edid;
234 	int ret;
235 
236 	edid = drm_bridge_get_edid(priv->next_bridge, connector);
237 	drm_connector_update_edid_property(connector, edid);
238 	if (edid) {
239 		ret = drm_add_edid_modes(connector, edid);
240 		kfree(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 
ch7033_connector_best_encoder(struct drm_connector * connector)249 static 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 
257 static 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 
ch7033_hpd_event(void * arg,enum drm_connector_status status)262 static 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 
ch7033_bridge_attach(struct drm_bridge * bridge,enum drm_bridge_attach_flags flags)270 static 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 
ch7033_bridge_detach(struct drm_bridge * bridge)311 static 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 
ch7033_bridge_mode_valid(struct drm_bridge * bridge,const struct drm_display_info * info,const struct drm_display_mode * mode)320 static 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 
ch7033_bridge_disable(struct drm_bridge * bridge)333 static 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 
ch7033_bridge_enable(struct drm_bridge * bridge)341 static 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 
ch7033_bridge_mode_set(struct drm_bridge * bridge,const struct drm_display_mode * mode,const struct drm_display_mode * adjusted_mode)349 static 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 
516 static 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 
525 static const struct regmap_config ch7033_regmap_config = {
526 	.reg_bits = 8,
527 	.val_bits = 8,
528 	.max_register = 0x7f,
529 };
530 
ch7033_probe(struct i2c_client * client)531 static 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 
ch7033_remove(struct i2c_client * client)585 static 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 
593 static const struct of_device_id ch7033_dt_ids[] = {
594 	{ .compatible = "chrontel,ch7033", },
595 	{ }
596 };
597 MODULE_DEVICE_TABLE(of, ch7033_dt_ids);
598 
599 static const struct i2c_device_id ch7033_ids[] = {
600 	{ "ch7033", 0 },
601 	{ }
602 };
603 MODULE_DEVICE_TABLE(i2c, ch7033_ids);
604 
605 static 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 
615 module_i2c_driver(ch7033_driver);
616 
617 MODULE_AUTHOR("Lubomir Rintel <lkundrak@v3.sk>");
618 MODULE_DESCRIPTION("Chrontel CH7033 Video Encoder Driver");
619 MODULE_LICENSE("GPL v2");
620