xref: /linux/drivers/media/i2c/ds90ub913.c (revision fbf5df34a4dbcd09d433dd4f0916bf9b2ddb16de)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Driver for the Texas Instruments DS90UB913 video serializer
4  *
5  * Based on a driver from Luca Ceresoli <luca@lucaceresoli.net>
6  *
7  * Copyright (c) 2019 Luca Ceresoli <luca@lucaceresoli.net>
8  * Copyright (c) 2023 Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
9  */
10 
11 #include <linux/bitfield.h>
12 #include <linux/clk-provider.h>
13 #include <linux/clk.h>
14 #include <linux/delay.h>
15 #include <linux/gpio/driver.h>
16 #include <linux/i2c-atr.h>
17 #include <linux/i2c.h>
18 #include <linux/kernel.h>
19 #include <linux/module.h>
20 #include <linux/property.h>
21 #include <linux/regmap.h>
22 
23 #include <media/i2c/ds90ub9xx.h>
24 #include <media/v4l2-fwnode.h>
25 #include <media/v4l2-mediabus.h>
26 #include <media/v4l2-subdev.h>
27 
28 #define UB913_PAD_SINK			0
29 #define UB913_PAD_SOURCE		1
30 
31 /*
32  * UB913 has 4 gpios, but gpios 3 and 4 are reserved for external oscillator
33  * mode. Thus we only support 2 gpios for now.
34  */
35 #define UB913_NUM_GPIOS			2
36 
37 #define UB913_REG_RESET_CTL			0x01
38 #define UB913_REG_RESET_CTL_DIGITAL_RESET_1	BIT(1)
39 #define UB913_REG_RESET_CTL_DIGITAL_RESET_0	BIT(0)
40 
41 #define UB913_REG_GENERAL_CFG			0x03
42 #define UB913_REG_GENERAL_CFG_CRC_ERR_RESET	BIT(5)
43 #define UB913_REG_GENERAL_CFG_PCLK_RISING	BIT(0)
44 
45 #define UB913_REG_MODE_SEL			0x05
46 #define UB913_REG_MODE_SEL_MODE_OVERRIDE	BIT(5)
47 #define UB913_REG_MODE_SEL_MODE_UP_TO_DATE	BIT(4)
48 #define UB913_REG_MODE_SEL_MODE_MASK		GENMASK(3, 0)
49 
50 #define UB913_REG_CRC_ERRORS_LSB		0x0a
51 #define UB913_REG_CRC_ERRORS_MSB		0x0b
52 
53 #define UB913_REG_GENERAL_STATUS		0x0c
54 
55 #define UB913_REG_GPIO_CFG(n)			(0x0d + (n))
56 #define UB913_REG_GPIO_CFG_ENABLE(n)		BIT(0 + (n) * 4)
57 #define UB913_REG_GPIO_CFG_DIR_INPUT(n)		BIT(1 + (n) * 4)
58 #define UB913_REG_GPIO_CFG_REMOTE_EN(n)		BIT(2 + (n) * 4)
59 #define UB913_REG_GPIO_CFG_OUT_VAL(n)		BIT(3 + (n) * 4)
60 #define UB913_REG_GPIO_CFG_MASK(n)		(0xf << ((n) * 4))
61 
62 #define UB913_REG_SCL_HIGH_TIME			0x11
63 #define UB913_REG_SCL_LOW_TIME			0x12
64 
65 #define UB913_REG_PLL_OVR			0x35
66 
67 struct ub913_data {
68 	struct i2c_client	*client;
69 	struct regmap		*regmap;
70 	struct clk		*clkin;
71 
72 	struct gpio_chip	gpio_chip;
73 
74 	struct v4l2_subdev	sd;
75 	struct media_pad	pads[2];
76 
77 	struct v4l2_async_notifier	notifier;
78 
79 	struct v4l2_subdev	*source_sd;
80 	u16			source_sd_pad;
81 
82 	u64			enabled_source_streams;
83 
84 	struct clk_hw		*clkout_clk_hw;
85 
86 	struct ds90ub9xx_platform_data *plat_data;
87 
88 	bool			pclk_polarity_rising;
89 };
90 
91 static inline struct ub913_data *sd_to_ub913(struct v4l2_subdev *sd)
92 {
93 	return container_of(sd, struct ub913_data, sd);
94 }
95 
96 struct ub913_format_info {
97 	u32 incode;
98 	u32 outcode;
99 };
100 
101 static const struct ub913_format_info ub913_formats[] = {
102 	/* Only RAW10 with 8-bit payload is supported at the moment */
103 	{ .incode = MEDIA_BUS_FMT_YUYV8_2X8, .outcode = MEDIA_BUS_FMT_YUYV8_1X16 },
104 	{ .incode = MEDIA_BUS_FMT_UYVY8_2X8, .outcode = MEDIA_BUS_FMT_UYVY8_1X16 },
105 	{ .incode = MEDIA_BUS_FMT_VYUY8_2X8, .outcode = MEDIA_BUS_FMT_VYUY8_1X16 },
106 	{ .incode = MEDIA_BUS_FMT_YVYU8_2X8, .outcode = MEDIA_BUS_FMT_YVYU8_1X16 },
107 };
108 
109 static const struct ub913_format_info *ub913_find_format(u32 incode)
110 {
111 	unsigned int i;
112 
113 	for (i = 0; i < ARRAY_SIZE(ub913_formats); i++) {
114 		if (ub913_formats[i].incode == incode)
115 			return &ub913_formats[i];
116 	}
117 
118 	return NULL;
119 }
120 
121 static int ub913_read(const struct ub913_data *priv, u8 reg, u8 *val,
122 		      int *err)
123 {
124 	unsigned int v;
125 	int ret;
126 
127 	if (err && *err)
128 		return *err;
129 
130 	ret = regmap_read(priv->regmap, reg, &v);
131 	if (ret) {
132 		dev_err(&priv->client->dev,
133 			"Cannot read register 0x%02x: %d!\n", reg, ret);
134 		goto out;
135 	}
136 
137 	*val = v;
138 
139 out:
140 	if (ret && err)
141 		*err = ret;
142 
143 	return ret;
144 }
145 
146 static int ub913_write(const struct ub913_data *priv, u8 reg, u8 val,
147 		       int *err)
148 {
149 	int ret;
150 
151 	if (err && *err)
152 		return *err;
153 
154 	ret = regmap_write(priv->regmap, reg, val);
155 	if (ret < 0)
156 		dev_err(&priv->client->dev,
157 			"Cannot write register 0x%02x: %d!\n", reg, ret);
158 
159 	if (ret && err)
160 		*err = ret;
161 
162 	return ret;
163 }
164 
165 static int ub913_update_bits(const struct ub913_data *priv, u8 reg, u8 mask,
166 			     u8 val, int *err)
167 {
168 	int ret;
169 
170 	if (err && *err)
171 		return *err;
172 
173 	ret = regmap_update_bits(priv->regmap, reg, mask, val);
174 	if (ret < 0)
175 		dev_err(&priv->client->dev,
176 			"Cannot update register 0x%02x %d!\n", reg, ret);
177 
178 	if (ret && err)
179 		*err = ret;
180 
181 	return ret;
182 }
183 
184 /*
185  * GPIO chip
186  */
187 static int ub913_gpio_get_direction(struct gpio_chip *gc, unsigned int offset)
188 {
189 	return GPIO_LINE_DIRECTION_OUT;
190 }
191 
192 static int ub913_gpio_direction_out(struct gpio_chip *gc, unsigned int offset,
193 				    int value)
194 {
195 	struct ub913_data *priv = gpiochip_get_data(gc);
196 	unsigned int reg_idx = offset / 2;
197 	unsigned int field_idx = offset % 2;
198 
199 	return regmap_update_bits(priv->regmap, UB913_REG_GPIO_CFG(reg_idx),
200 				  UB913_REG_GPIO_CFG_MASK(field_idx),
201 				  UB913_REG_GPIO_CFG_ENABLE(field_idx) |
202 					  (value ? UB913_REG_GPIO_CFG_OUT_VAL(field_idx) :
203 						   0));
204 }
205 
206 static int ub913_gpio_set(struct gpio_chip *gc, unsigned int offset, int value)
207 {
208 	return ub913_gpio_direction_out(gc, offset, value);
209 }
210 
211 static int ub913_gpio_of_xlate(struct gpio_chip *gc,
212 			       const struct of_phandle_args *gpiospec,
213 			       u32 *flags)
214 {
215 	if (flags)
216 		*flags = gpiospec->args[1];
217 
218 	return gpiospec->args[0];
219 }
220 
221 static int ub913_gpiochip_probe(struct ub913_data *priv)
222 {
223 	struct device *dev = &priv->client->dev;
224 	struct gpio_chip *gc = &priv->gpio_chip;
225 	int ret;
226 
227 	/* Initialize GPIOs 0 and 1 to local control, tri-state */
228 	ub913_write(priv, UB913_REG_GPIO_CFG(0), 0, NULL);
229 
230 	gc->label = dev_name(dev);
231 	gc->parent = dev;
232 	gc->owner = THIS_MODULE;
233 	gc->base = -1;
234 	gc->can_sleep = true;
235 	gc->ngpio = UB913_NUM_GPIOS;
236 	gc->get_direction = ub913_gpio_get_direction;
237 	gc->direction_output = ub913_gpio_direction_out;
238 	gc->set = ub913_gpio_set;
239 	gc->of_xlate = ub913_gpio_of_xlate;
240 	gc->of_gpio_n_cells = 2;
241 
242 	ret = gpiochip_add_data(gc, priv);
243 	if (ret) {
244 		dev_err(dev, "Failed to add GPIOs: %d\n", ret);
245 		return ret;
246 	}
247 
248 	return 0;
249 }
250 
251 static void ub913_gpiochip_remove(struct ub913_data *priv)
252 {
253 	gpiochip_remove(&priv->gpio_chip);
254 }
255 
256 static const struct regmap_config ub913_regmap_config = {
257 	.name = "ds90ub913",
258 	.reg_bits = 8,
259 	.val_bits = 8,
260 	.reg_format_endian = REGMAP_ENDIAN_DEFAULT,
261 	.val_format_endian = REGMAP_ENDIAN_DEFAULT,
262 };
263 
264 /*
265  * V4L2
266  */
267 
268 static int ub913_enable_streams(struct v4l2_subdev *sd,
269 				struct v4l2_subdev_state *state, u32 pad,
270 				u64 streams_mask)
271 {
272 	struct ub913_data *priv = sd_to_ub913(sd);
273 	u64 sink_streams;
274 	int ret;
275 
276 	sink_streams = v4l2_subdev_state_xlate_streams(state, UB913_PAD_SOURCE,
277 						       UB913_PAD_SINK,
278 						       &streams_mask);
279 
280 	ret = v4l2_subdev_enable_streams(priv->source_sd, priv->source_sd_pad,
281 					 sink_streams);
282 	if (ret)
283 		return ret;
284 
285 	priv->enabled_source_streams |= streams_mask;
286 
287 	return 0;
288 }
289 
290 static int ub913_disable_streams(struct v4l2_subdev *sd,
291 				 struct v4l2_subdev_state *state, u32 pad,
292 				 u64 streams_mask)
293 {
294 	struct ub913_data *priv = sd_to_ub913(sd);
295 	u64 sink_streams;
296 	int ret;
297 
298 	sink_streams = v4l2_subdev_state_xlate_streams(state, UB913_PAD_SOURCE,
299 						       UB913_PAD_SINK,
300 						       &streams_mask);
301 
302 	ret = v4l2_subdev_disable_streams(priv->source_sd, priv->source_sd_pad,
303 					  sink_streams);
304 	if (ret)
305 		return ret;
306 
307 	priv->enabled_source_streams &= ~streams_mask;
308 
309 	return 0;
310 }
311 
312 static int _ub913_set_routing(struct v4l2_subdev *sd,
313 			      struct v4l2_subdev_state *state,
314 			      struct v4l2_subdev_krouting *routing)
315 {
316 	static const struct v4l2_mbus_framefmt in_format = {
317 		.width = 640,
318 		.height = 480,
319 		.code = MEDIA_BUS_FMT_UYVY8_2X8,
320 		.field = V4L2_FIELD_NONE,
321 		.colorspace = V4L2_COLORSPACE_SRGB,
322 		.ycbcr_enc = V4L2_YCBCR_ENC_601,
323 		.quantization = V4L2_QUANTIZATION_LIM_RANGE,
324 		.xfer_func = V4L2_XFER_FUNC_SRGB,
325 	};
326 	static const struct v4l2_mbus_framefmt out_format = {
327 		.width = 640,
328 		.height = 480,
329 		.code = MEDIA_BUS_FMT_UYVY8_1X16,
330 		.field = V4L2_FIELD_NONE,
331 		.colorspace = V4L2_COLORSPACE_SRGB,
332 		.ycbcr_enc = V4L2_YCBCR_ENC_601,
333 		.quantization = V4L2_QUANTIZATION_LIM_RANGE,
334 		.xfer_func = V4L2_XFER_FUNC_SRGB,
335 	};
336 	struct v4l2_subdev_route *route;
337 	int ret;
338 
339 	ret = v4l2_subdev_routing_validate(sd, routing,
340 					   V4L2_SUBDEV_ROUTING_ONLY_1_TO_1);
341 	if (ret)
342 		return ret;
343 
344 	ret = v4l2_subdev_set_routing(sd, state, routing);
345 	if (ret)
346 		return ret;
347 
348 	for_each_active_route(&state->routing, route) {
349 		struct v4l2_mbus_framefmt *fmt;
350 
351 		fmt = v4l2_subdev_state_get_format(state, route->sink_pad,
352 						   route->sink_stream);
353 		*fmt = in_format;
354 		fmt = v4l2_subdev_state_get_format(state, route->source_pad,
355 						   route->source_stream);
356 		*fmt = out_format;
357 	}
358 
359 	return 0;
360 }
361 
362 static int ub913_set_routing(struct v4l2_subdev *sd,
363 			     struct v4l2_subdev_state *state,
364 			     enum v4l2_subdev_format_whence which,
365 			     struct v4l2_subdev_krouting *routing)
366 {
367 	struct ub913_data *priv = sd_to_ub913(sd);
368 
369 	if (which == V4L2_SUBDEV_FORMAT_ACTIVE && priv->enabled_source_streams)
370 		return -EBUSY;
371 
372 	return _ub913_set_routing(sd, state, routing);
373 }
374 
375 static int ub913_set_fmt(struct v4l2_subdev *sd,
376 			 struct v4l2_subdev_state *state,
377 			 struct v4l2_subdev_format *format)
378 {
379 	struct ub913_data *priv = sd_to_ub913(sd);
380 	struct v4l2_mbus_framefmt *fmt;
381 	const struct ub913_format_info *finfo;
382 
383 	if (format->which == V4L2_SUBDEV_FORMAT_ACTIVE &&
384 	    priv->enabled_source_streams)
385 		return -EBUSY;
386 
387 	/* Source format is fully defined by the sink format, so not settable */
388 	if (format->pad == UB913_PAD_SOURCE)
389 		return v4l2_subdev_get_fmt(sd, state, format);
390 
391 	finfo = ub913_find_format(format->format.code);
392 	if (!finfo) {
393 		finfo = &ub913_formats[0];
394 		format->format.code = finfo->incode;
395 	}
396 
397 	/* Set sink format */
398 	fmt = v4l2_subdev_state_get_format(state, format->pad, format->stream);
399 	if (!fmt)
400 		return -EINVAL;
401 
402 	*fmt = format->format;
403 
404 	/* Propagate to source format, and adjust the mbus code */
405 	fmt = v4l2_subdev_state_get_opposite_stream_format(state, format->pad,
406 							   format->stream);
407 	if (!fmt)
408 		return -EINVAL;
409 
410 	*fmt = format->format;
411 
412 	fmt->code = finfo->outcode;
413 
414 	return 0;
415 }
416 
417 static int ub913_init_state(struct v4l2_subdev *sd,
418 			    struct v4l2_subdev_state *state)
419 {
420 	struct v4l2_subdev_route routes[] = {
421 		{
422 			.sink_pad = UB913_PAD_SINK,
423 			.sink_stream = 0,
424 			.source_pad = UB913_PAD_SOURCE,
425 			.source_stream = 0,
426 			.flags = V4L2_SUBDEV_ROUTE_FL_ACTIVE,
427 		},
428 	};
429 
430 	struct v4l2_subdev_krouting routing = {
431 		.num_routes = ARRAY_SIZE(routes),
432 		.routes = routes,
433 	};
434 
435 	return _ub913_set_routing(sd, state, &routing);
436 }
437 
438 static int ub913_log_status(struct v4l2_subdev *sd)
439 {
440 	struct ub913_data *priv = sd_to_ub913(sd);
441 	struct device *dev = &priv->client->dev;
442 	u8 v, v1, v2;
443 	int ret;
444 
445 	ret = ub913_read(priv, UB913_REG_MODE_SEL, &v, NULL);
446 	if (ret)
447 		return ret;
448 
449 	dev_info(dev, "MODE_SEL %#02x\n", v);
450 
451 	ub913_read(priv, UB913_REG_CRC_ERRORS_LSB, &v1, &ret);
452 	ub913_read(priv, UB913_REG_CRC_ERRORS_MSB, &v2, &ret);
453 	if (ret)
454 		return ret;
455 
456 	dev_info(dev, "CRC errors %u\n", v1 | (v2 << 8));
457 
458 	/* clear CRC errors */
459 	ub913_read(priv, UB913_REG_GENERAL_CFG, &v, &ret);
460 	ub913_write(priv, UB913_REG_GENERAL_CFG,
461 		    v | UB913_REG_GENERAL_CFG_CRC_ERR_RESET, &ret);
462 	ub913_write(priv, UB913_REG_GENERAL_CFG, v, &ret);
463 
464 	if (ret)
465 		return ret;
466 
467 	ret = ub913_read(priv, UB913_REG_GENERAL_STATUS, &v, NULL);
468 	if (ret)
469 		return ret;
470 
471 	dev_info(dev, "GENERAL_STATUS %#02x\n", v);
472 
473 	ret = ub913_read(priv, UB913_REG_PLL_OVR, &v, NULL);
474 	if (ret)
475 		return ret;
476 
477 	dev_info(dev, "PLL_OVR %#02x\n", v);
478 
479 	return 0;
480 }
481 
482 static const struct v4l2_subdev_core_ops ub913_subdev_core_ops = {
483 	.log_status = ub913_log_status,
484 };
485 
486 static const struct v4l2_subdev_pad_ops ub913_pad_ops = {
487 	.enable_streams = ub913_enable_streams,
488 	.disable_streams = ub913_disable_streams,
489 	.set_routing = ub913_set_routing,
490 	.get_frame_desc = v4l2_subdev_get_frame_desc_passthrough,
491 	.get_fmt = v4l2_subdev_get_fmt,
492 	.set_fmt = ub913_set_fmt,
493 };
494 
495 static const struct v4l2_subdev_ops ub913_subdev_ops = {
496 	.core = &ub913_subdev_core_ops,
497 	.pad = &ub913_pad_ops,
498 };
499 
500 static const struct v4l2_subdev_internal_ops ub913_internal_ops = {
501 	.init_state = ub913_init_state,
502 };
503 
504 static const struct media_entity_operations ub913_entity_ops = {
505 	.link_validate = v4l2_subdev_link_validate,
506 };
507 
508 static int ub913_notify_bound(struct v4l2_async_notifier *notifier,
509 			      struct v4l2_subdev *source_subdev,
510 			      struct v4l2_async_connection *asd)
511 {
512 	struct ub913_data *priv = sd_to_ub913(notifier->sd);
513 	struct device *dev = &priv->client->dev;
514 	int ret;
515 
516 	ret = media_entity_get_fwnode_pad(&source_subdev->entity,
517 					  source_subdev->fwnode,
518 					  MEDIA_PAD_FL_SOURCE);
519 	if (ret < 0) {
520 		dev_err(dev, "Failed to find pad for %s\n",
521 			source_subdev->name);
522 		return ret;
523 	}
524 
525 	priv->source_sd = source_subdev;
526 	priv->source_sd_pad = ret;
527 
528 	ret = media_create_pad_link(&source_subdev->entity, priv->source_sd_pad,
529 				    &priv->sd.entity, UB913_PAD_SINK,
530 				    MEDIA_LNK_FL_ENABLED |
531 					    MEDIA_LNK_FL_IMMUTABLE);
532 	if (ret) {
533 		dev_err(dev, "Unable to link %s:%u -> %s:0\n",
534 			source_subdev->name, priv->source_sd_pad,
535 			priv->sd.name);
536 		return ret;
537 	}
538 
539 	return 0;
540 }
541 
542 static const struct v4l2_async_notifier_operations ub913_notify_ops = {
543 	.bound = ub913_notify_bound,
544 };
545 
546 static int ub913_v4l2_notifier_register(struct ub913_data *priv)
547 {
548 	struct device *dev = &priv->client->dev;
549 	struct v4l2_async_connection *asd;
550 	struct fwnode_handle *ep_fwnode;
551 	int ret;
552 
553 	ep_fwnode = fwnode_graph_get_endpoint_by_id(dev_fwnode(dev),
554 						    UB913_PAD_SINK, 0, 0);
555 	if (!ep_fwnode) {
556 		dev_err(dev, "No graph endpoint\n");
557 		return -ENODEV;
558 	}
559 
560 	v4l2_async_subdev_nf_init(&priv->notifier, &priv->sd);
561 
562 	asd = v4l2_async_nf_add_fwnode_remote(&priv->notifier, ep_fwnode,
563 					      struct v4l2_async_connection);
564 
565 	fwnode_handle_put(ep_fwnode);
566 
567 	if (IS_ERR(asd)) {
568 		dev_err(dev, "Failed to add subdev: %pe", asd);
569 		v4l2_async_nf_cleanup(&priv->notifier);
570 		return PTR_ERR(asd);
571 	}
572 
573 	priv->notifier.ops = &ub913_notify_ops;
574 
575 	ret = v4l2_async_nf_register(&priv->notifier);
576 	if (ret) {
577 		dev_err(dev, "Failed to register subdev_notifier");
578 		v4l2_async_nf_cleanup(&priv->notifier);
579 		return ret;
580 	}
581 
582 	return 0;
583 }
584 
585 static void ub913_v4l2_nf_unregister(struct ub913_data *priv)
586 {
587 	v4l2_async_nf_unregister(&priv->notifier);
588 	v4l2_async_nf_cleanup(&priv->notifier);
589 }
590 
591 static int ub913_register_clkout(struct ub913_data *priv)
592 {
593 	struct device *dev = &priv->client->dev;
594 	const char *name;
595 	int ret;
596 
597 	name = kasprintf(GFP_KERNEL, "ds90ub913.%s.clk_out", dev_name(dev));
598 	if (!name)
599 		return -ENOMEM;
600 
601 	priv->clkout_clk_hw = devm_clk_hw_register_fixed_factor(dev, name,
602 		__clk_get_name(priv->clkin), 0, 1, 2);
603 
604 	kfree(name);
605 
606 	if (IS_ERR(priv->clkout_clk_hw))
607 		return dev_err_probe(dev, PTR_ERR(priv->clkout_clk_hw),
608 				     "Cannot register clkout hw\n");
609 
610 	ret = devm_of_clk_add_hw_provider(dev, of_clk_hw_simple_get,
611 					  priv->clkout_clk_hw);
612 	if (ret)
613 		return dev_err_probe(dev, ret,
614 				     "Cannot add OF clock provider\n");
615 
616 	return 0;
617 }
618 
619 static int ub913_i2c_master_init(struct ub913_data *priv)
620 {
621 	/* i2c fast mode */
622 	u32 scl_high = 600 + 300; /* high period + rise time, ns */
623 	u32 scl_low = 1300 + 300; /* low period + fall time, ns */
624 	unsigned long ref;
625 	int ret;
626 
627 	ref = clk_get_rate(priv->clkin) / 2;
628 
629 	scl_high = div64_u64((u64)scl_high * ref, 1000000000);
630 	scl_low = div64_u64((u64)scl_low * ref, 1000000000);
631 
632 	ret = ub913_write(priv, UB913_REG_SCL_HIGH_TIME, scl_high, NULL);
633 	if (ret)
634 		return ret;
635 
636 	ret = ub913_write(priv, UB913_REG_SCL_LOW_TIME, scl_low, NULL);
637 	if (ret)
638 		return ret;
639 
640 	return 0;
641 }
642 
643 static int ub913_add_i2c_adapter(struct ub913_data *priv)
644 {
645 	struct device *dev = &priv->client->dev;
646 	struct i2c_atr_adap_desc desc = { };
647 	struct fwnode_handle *i2c_handle;
648 	int ret;
649 
650 	i2c_handle = device_get_named_child_node(dev, "i2c");
651 	if (!i2c_handle)
652 		return 0;
653 
654 	desc.chan_id = priv->plat_data->port;
655 	desc.parent = dev;
656 	desc.bus_handle = i2c_handle;
657 	desc.num_aliases = 0;
658 
659 	ret = i2c_atr_add_adapter(priv->plat_data->atr, &desc);
660 
661 	fwnode_handle_put(i2c_handle);
662 
663 	if (ret)
664 		return ret;
665 
666 	return 0;
667 }
668 
669 static int ub913_parse_dt(struct ub913_data *priv)
670 {
671 	struct device *dev = &priv->client->dev;
672 	struct v4l2_fwnode_endpoint vep = {
673 		.bus_type = V4L2_MBUS_PARALLEL,
674 	};
675 	struct fwnode_handle *ep_fwnode;
676 	int ret;
677 
678 	ep_fwnode = fwnode_graph_get_endpoint_by_id(dev_fwnode(dev),
679 						    UB913_PAD_SINK, 0, 0);
680 	if (!ep_fwnode)
681 		return dev_err_probe(dev, -ENOENT, "No sink endpoint\n");
682 
683 	ret = v4l2_fwnode_endpoint_parse(ep_fwnode, &vep);
684 
685 	fwnode_handle_put(ep_fwnode);
686 
687 	if (ret)
688 		return dev_err_probe(dev, ret,
689 				     "failed to parse sink endpoint data\n");
690 
691 	if (vep.bus.parallel.flags & V4L2_MBUS_PCLK_SAMPLE_RISING)
692 		priv->pclk_polarity_rising = true;
693 	else if (vep.bus.parallel.flags & V4L2_MBUS_PCLK_SAMPLE_FALLING)
694 		priv->pclk_polarity_rising = false;
695 	else
696 		return dev_err_probe(dev, -EINVAL,
697 				     "bad value for 'pclk-sample'\n");
698 
699 	return 0;
700 }
701 
702 static int ub913_hw_init(struct ub913_data *priv)
703 {
704 	struct device *dev = &priv->client->dev;
705 	bool mode_override;
706 	u8 mode;
707 	int ret;
708 	u8 v;
709 
710 	ret = ub913_read(priv, UB913_REG_MODE_SEL, &v, NULL);
711 	if (ret)
712 		return ret;
713 
714 	if (!(v & UB913_REG_MODE_SEL_MODE_UP_TO_DATE))
715 		return dev_err_probe(dev, -ENODEV,
716 				     "Mode value not stabilized\n");
717 
718 	mode_override = v & UB913_REG_MODE_SEL_MODE_OVERRIDE;
719 	mode = v & UB913_REG_MODE_SEL_MODE_MASK;
720 
721 	dev_dbg(dev, "mode from %s: %#x\n",
722 		mode_override ? "reg" : "deserializer", mode);
723 
724 	ret = ub913_i2c_master_init(priv);
725 	if (ret)
726 		return dev_err_probe(dev, ret, "i2c master init failed\n");
727 
728 	ret = ub913_update_bits(priv, UB913_REG_GENERAL_CFG,
729 				UB913_REG_GENERAL_CFG_PCLK_RISING,
730 				FIELD_PREP(UB913_REG_GENERAL_CFG_PCLK_RISING,
731 					   priv->pclk_polarity_rising), NULL);
732 
733 	if (ret)
734 		return ret;
735 
736 	return 0;
737 }
738 
739 static int ub913_subdev_init(struct ub913_data *priv)
740 {
741 	struct device *dev = &priv->client->dev;
742 	int ret;
743 
744 	v4l2_i2c_subdev_init(&priv->sd, priv->client, &ub913_subdev_ops);
745 	priv->sd.internal_ops = &ub913_internal_ops;
746 	priv->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE | V4L2_SUBDEV_FL_STREAMS;
747 	priv->sd.entity.function = MEDIA_ENT_F_VID_IF_BRIDGE;
748 	priv->sd.entity.ops = &ub913_entity_ops;
749 
750 	priv->pads[0].flags = MEDIA_PAD_FL_SINK;
751 	priv->pads[1].flags = MEDIA_PAD_FL_SOURCE;
752 
753 	ret = media_entity_pads_init(&priv->sd.entity, 2, priv->pads);
754 	if (ret)
755 		return dev_err_probe(dev, ret, "Failed to init pads\n");
756 
757 	ret = v4l2_subdev_init_finalize(&priv->sd);
758 	if (ret)
759 		goto err_entity_cleanup;
760 
761 	ret = ub913_v4l2_notifier_register(priv);
762 	if (ret) {
763 		dev_err_probe(dev, ret,
764 			      "v4l2 subdev notifier register failed\n");
765 		goto err_subdev_cleanup;
766 	}
767 
768 	ret = v4l2_async_register_subdev(&priv->sd);
769 	if (ret) {
770 		dev_err_probe(dev, ret, "v4l2_async_register_subdev error\n");
771 		goto err_unreg_notif;
772 	}
773 
774 	return 0;
775 
776 err_unreg_notif:
777 	ub913_v4l2_nf_unregister(priv);
778 err_subdev_cleanup:
779 	v4l2_subdev_cleanup(&priv->sd);
780 err_entity_cleanup:
781 	media_entity_cleanup(&priv->sd.entity);
782 
783 	return ret;
784 }
785 
786 static void ub913_subdev_uninit(struct ub913_data *priv)
787 {
788 	v4l2_async_unregister_subdev(&priv->sd);
789 	ub913_v4l2_nf_unregister(priv);
790 	v4l2_subdev_cleanup(&priv->sd);
791 	media_entity_cleanup(&priv->sd.entity);
792 }
793 
794 static int ub913_probe(struct i2c_client *client)
795 {
796 	struct device *dev = &client->dev;
797 	struct ub913_data *priv;
798 	int ret;
799 
800 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
801 	if (!priv)
802 		return -ENOMEM;
803 
804 	priv->client = client;
805 
806 	priv->plat_data = dev_get_platdata(&client->dev);
807 	if (!priv->plat_data)
808 		return dev_err_probe(dev, -ENODEV, "Platform data missing\n");
809 
810 	priv->regmap = devm_regmap_init_i2c(client, &ub913_regmap_config);
811 	if (IS_ERR(priv->regmap))
812 		return dev_err_probe(dev, PTR_ERR(priv->regmap),
813 				     "Failed to init regmap\n");
814 
815 	/*
816 	 * ub913 can also work without ext clock, but that is not supported by
817 	 * the driver yet.
818 	 */
819 	priv->clkin = devm_clk_get(dev, "clkin");
820 	if (IS_ERR(priv->clkin))
821 		return dev_err_probe(dev, PTR_ERR(priv->clkin),
822 				     "Cannot get CLKIN\n");
823 
824 	ret = ub913_parse_dt(priv);
825 	if (ret)
826 		return ret;
827 
828 	ret = ub913_hw_init(priv);
829 	if (ret)
830 		return ret;
831 
832 	ret = ub913_gpiochip_probe(priv);
833 	if (ret)
834 		return dev_err_probe(dev, ret, "Failed to init gpiochip\n");
835 
836 	ret = ub913_register_clkout(priv);
837 	if (ret) {
838 		dev_err_probe(dev, ret, "Failed to register clkout\n");
839 		goto err_gpiochip_remove;
840 	}
841 
842 	ret = ub913_subdev_init(priv);
843 	if (ret)
844 		goto err_gpiochip_remove;
845 
846 	ret = ub913_add_i2c_adapter(priv);
847 	if (ret) {
848 		dev_err_probe(dev, ret, "failed to add remote i2c adapter\n");
849 		goto err_subdev_uninit;
850 	}
851 
852 	return 0;
853 
854 err_subdev_uninit:
855 	ub913_subdev_uninit(priv);
856 err_gpiochip_remove:
857 	ub913_gpiochip_remove(priv);
858 
859 	return ret;
860 }
861 
862 static void ub913_remove(struct i2c_client *client)
863 {
864 	struct v4l2_subdev *sd = i2c_get_clientdata(client);
865 	struct ub913_data *priv = sd_to_ub913(sd);
866 
867 	i2c_atr_del_adapter(priv->plat_data->atr, priv->plat_data->port);
868 
869 	ub913_subdev_uninit(priv);
870 
871 	ub913_gpiochip_remove(priv);
872 }
873 
874 static const struct i2c_device_id ub913_id[] = {
875 	{ "ds90ub913a-q1" },
876 	{}
877 };
878 MODULE_DEVICE_TABLE(i2c, ub913_id);
879 
880 static const struct of_device_id ub913_dt_ids[] = {
881 	{ .compatible = "ti,ds90ub913a-q1" },
882 	{}
883 };
884 MODULE_DEVICE_TABLE(of, ub913_dt_ids);
885 
886 static struct i2c_driver ds90ub913_driver = {
887 	.probe		= ub913_probe,
888 	.remove		= ub913_remove,
889 	.id_table	= ub913_id,
890 	.driver = {
891 		.name	= "ds90ub913a",
892 		.of_match_table = ub913_dt_ids,
893 	},
894 };
895 module_i2c_driver(ds90ub913_driver);
896 
897 MODULE_LICENSE("GPL");
898 MODULE_DESCRIPTION("Texas Instruments DS90UB913 FPD-Link III Serializer Driver");
899 MODULE_AUTHOR("Luca Ceresoli <luca@lucaceresoli.net>");
900 MODULE_AUTHOR("Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>");
901 MODULE_IMPORT_NS("I2C_ATR");
902