1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Driver for Cadence MIPI-CSI2 TX Controller
4  *
5  * Copyright (C) 2017-2019 Cadence Design Systems Inc.
6  */
7 
8 #include <linux/clk.h>
9 #include <linux/delay.h>
10 #include <linux/io.h>
11 #include <linux/module.h>
12 #include <linux/mutex.h>
13 #include <linux/of.h>
14 #include <linux/of_graph.h>
15 #include <linux/platform_device.h>
16 #include <linux/slab.h>
17 
18 #include <media/mipi-csi2.h>
19 #include <media/v4l2-ctrls.h>
20 #include <media/v4l2-device.h>
21 #include <media/v4l2-fwnode.h>
22 #include <media/v4l2-subdev.h>
23 
24 #define CSI2TX_DEVICE_CONFIG_REG	0x00
25 #define CSI2TX_DEVICE_CONFIG_STREAMS_MASK	GENMASK(6, 4)
26 #define CSI2TX_DEVICE_CONFIG_HAS_DPHY		BIT(3)
27 #define CSI2TX_DEVICE_CONFIG_LANES_MASK		GENMASK(2, 0)
28 
29 #define CSI2TX_CONFIG_REG		0x20
30 #define CSI2TX_CONFIG_CFG_REQ			BIT(2)
31 #define CSI2TX_CONFIG_SRST_REQ			BIT(1)
32 
33 #define CSI2TX_DPHY_CFG_REG		0x28
34 #define CSI2TX_DPHY_CFG_CLK_RESET		BIT(16)
35 #define CSI2TX_DPHY_CFG_LANE_RESET(n)		BIT((n) + 12)
36 #define CSI2TX_DPHY_CFG_MODE_MASK		GENMASK(9, 8)
37 #define CSI2TX_DPHY_CFG_MODE_LPDT		(2 << 8)
38 #define CSI2TX_DPHY_CFG_MODE_HS			(1 << 8)
39 #define CSI2TX_DPHY_CFG_MODE_ULPS		(0 << 8)
40 #define CSI2TX_DPHY_CFG_CLK_ENABLE		BIT(4)
41 #define CSI2TX_DPHY_CFG_LANE_ENABLE(n)		BIT(n)
42 
43 #define CSI2TX_DPHY_CLK_WAKEUP_REG	0x2c
44 #define CSI2TX_DPHY_CLK_WAKEUP_ULPS_CYCLES(n)	((n) & 0xffff)
45 
46 #define CSI2TX_DT_CFG_REG(n)		(0x80 + (n) * 8)
47 #define CSI2TX_DT_CFG_DT(n)			(((n) & 0x3f) << 2)
48 
49 #define CSI2TX_DT_FORMAT_REG(n)		(0x84 + (n) * 8)
50 #define CSI2TX_DT_FORMAT_BYTES_PER_LINE(n)	(((n) & 0xffff) << 16)
51 #define CSI2TX_DT_FORMAT_MAX_LINE_NUM(n)	((n) & 0xffff)
52 
53 #define CSI2TX_STREAM_IF_CFG_REG(n)	(0x100 + (n) * 4)
54 #define CSI2TX_STREAM_IF_CFG_FILL_LEVEL(n)	((n) & 0x1f)
55 
56 /* CSI2TX V2 Registers */
57 #define CSI2TX_V2_DPHY_CFG_REG			0x28
58 #define CSI2TX_V2_DPHY_CFG_RESET		BIT(16)
59 #define CSI2TX_V2_DPHY_CFG_CLOCK_MODE		BIT(10)
60 #define CSI2TX_V2_DPHY_CFG_MODE_MASK		GENMASK(9, 8)
61 #define CSI2TX_V2_DPHY_CFG_MODE_LPDT		(2 << 8)
62 #define CSI2TX_V2_DPHY_CFG_MODE_HS		(1 << 8)
63 #define CSI2TX_V2_DPHY_CFG_MODE_ULPS		(0 << 8)
64 #define CSI2TX_V2_DPHY_CFG_CLK_ENABLE		BIT(4)
65 #define CSI2TX_V2_DPHY_CFG_LANE_ENABLE(n)	BIT(n)
66 
67 #define CSI2TX_LANES_MAX	4
68 #define CSI2TX_STREAMS_MAX	4
69 
70 enum csi2tx_pads {
71 	CSI2TX_PAD_SOURCE,
72 	CSI2TX_PAD_SINK_STREAM0,
73 	CSI2TX_PAD_SINK_STREAM1,
74 	CSI2TX_PAD_SINK_STREAM2,
75 	CSI2TX_PAD_SINK_STREAM3,
76 	CSI2TX_PAD_MAX,
77 };
78 
79 struct csi2tx_fmt {
80 	u32	mbus;
81 	u32	dt;
82 	u32	bpp;
83 };
84 
85 struct csi2tx_priv;
86 
87 /* CSI2TX Variant Operations */
88 struct csi2tx_vops {
89 	void (*dphy_setup)(struct csi2tx_priv *csi2tx);
90 };
91 
92 struct csi2tx_priv {
93 	struct device			*dev;
94 	unsigned int			count;
95 
96 	/*
97 	 * Used to prevent race conditions between multiple,
98 	 * concurrent calls to start and stop.
99 	 */
100 	struct mutex			lock;
101 
102 	void __iomem			*base;
103 
104 	struct csi2tx_vops		*vops;
105 
106 	struct clk			*esc_clk;
107 	struct clk			*p_clk;
108 	struct clk			*pixel_clk[CSI2TX_STREAMS_MAX];
109 
110 	struct v4l2_subdev		subdev;
111 	struct media_pad		pads[CSI2TX_PAD_MAX];
112 	struct v4l2_mbus_framefmt	pad_fmts[CSI2TX_PAD_MAX];
113 
114 	bool				has_internal_dphy;
115 	u8				lanes[CSI2TX_LANES_MAX];
116 	unsigned int			num_lanes;
117 	unsigned int			max_lanes;
118 	unsigned int			max_streams;
119 };
120 
121 static const struct csi2tx_fmt csi2tx_formats[] = {
122 	{
123 		.mbus	= MEDIA_BUS_FMT_UYVY8_1X16,
124 		.bpp	= 2,
125 		.dt	= MIPI_CSI2_DT_YUV422_8B,
126 	},
127 	{
128 		.mbus	= MEDIA_BUS_FMT_RGB888_1X24,
129 		.bpp	= 3,
130 		.dt	= MIPI_CSI2_DT_RGB888,
131 	},
132 };
133 
134 static const struct v4l2_mbus_framefmt fmt_default = {
135 	.width		= 1280,
136 	.height		= 720,
137 	.code		= MEDIA_BUS_FMT_RGB888_1X24,
138 	.field		= V4L2_FIELD_NONE,
139 	.colorspace	= V4L2_COLORSPACE_DEFAULT,
140 };
141 
142 static inline
143 struct csi2tx_priv *v4l2_subdev_to_csi2tx(struct v4l2_subdev *subdev)
144 {
145 	return container_of(subdev, struct csi2tx_priv, subdev);
146 }
147 
148 static const struct csi2tx_fmt *csi2tx_get_fmt_from_mbus(u32 mbus)
149 {
150 	unsigned int i;
151 
152 	for (i = 0; i < ARRAY_SIZE(csi2tx_formats); i++)
153 		if (csi2tx_formats[i].mbus == mbus)
154 			return &csi2tx_formats[i];
155 
156 	return NULL;
157 }
158 
159 static int csi2tx_enum_mbus_code(struct v4l2_subdev *subdev,
160 				 struct v4l2_subdev_state *sd_state,
161 				 struct v4l2_subdev_mbus_code_enum *code)
162 {
163 	if (code->pad || code->index >= ARRAY_SIZE(csi2tx_formats))
164 		return -EINVAL;
165 
166 	code->code = csi2tx_formats[code->index].mbus;
167 
168 	return 0;
169 }
170 
171 static struct v4l2_mbus_framefmt *
172 __csi2tx_get_pad_format(struct v4l2_subdev *subdev,
173 			struct v4l2_subdev_state *sd_state,
174 			struct v4l2_subdev_format *fmt)
175 {
176 	struct csi2tx_priv *csi2tx = v4l2_subdev_to_csi2tx(subdev);
177 
178 	if (fmt->which == V4L2_SUBDEV_FORMAT_TRY)
179 		return v4l2_subdev_get_try_format(subdev, sd_state,
180 						  fmt->pad);
181 
182 	return &csi2tx->pad_fmts[fmt->pad];
183 }
184 
185 static int csi2tx_get_pad_format(struct v4l2_subdev *subdev,
186 				 struct v4l2_subdev_state *sd_state,
187 				 struct v4l2_subdev_format *fmt)
188 {
189 	const struct v4l2_mbus_framefmt *format;
190 
191 	/* Multiplexed pad? */
192 	if (fmt->pad == CSI2TX_PAD_SOURCE)
193 		return -EINVAL;
194 
195 	format = __csi2tx_get_pad_format(subdev, sd_state, fmt);
196 	if (!format)
197 		return -EINVAL;
198 
199 	fmt->format = *format;
200 
201 	return 0;
202 }
203 
204 static int csi2tx_set_pad_format(struct v4l2_subdev *subdev,
205 				 struct v4l2_subdev_state *sd_state,
206 				 struct v4l2_subdev_format *fmt)
207 {
208 	const struct v4l2_mbus_framefmt *src_format = &fmt->format;
209 	struct v4l2_mbus_framefmt *dst_format;
210 
211 	/* Multiplexed pad? */
212 	if (fmt->pad == CSI2TX_PAD_SOURCE)
213 		return -EINVAL;
214 
215 	if (!csi2tx_get_fmt_from_mbus(fmt->format.code))
216 		src_format = &fmt_default;
217 
218 	dst_format = __csi2tx_get_pad_format(subdev, sd_state, fmt);
219 	if (!dst_format)
220 		return -EINVAL;
221 
222 	*dst_format = *src_format;
223 
224 	return 0;
225 }
226 
227 static const struct v4l2_subdev_pad_ops csi2tx_pad_ops = {
228 	.enum_mbus_code	= csi2tx_enum_mbus_code,
229 	.get_fmt	= csi2tx_get_pad_format,
230 	.set_fmt	= csi2tx_set_pad_format,
231 };
232 
233 /* Set Wake Up value in the D-PHY */
234 static void csi2tx_dphy_set_wakeup(struct csi2tx_priv *csi2tx)
235 {
236 	writel(CSI2TX_DPHY_CLK_WAKEUP_ULPS_CYCLES(32),
237 	       csi2tx->base + CSI2TX_DPHY_CLK_WAKEUP_REG);
238 }
239 
240 /*
241  * Finishes the D-PHY initialization
242  * reg dphy cfg value to be used
243  */
244 static void csi2tx_dphy_init_finish(struct csi2tx_priv *csi2tx, u32 reg)
245 {
246 	unsigned int i;
247 
248 	udelay(10);
249 
250 	/* Enable our (clock and data) lanes */
251 	reg |= CSI2TX_DPHY_CFG_CLK_ENABLE;
252 	for (i = 0; i < csi2tx->num_lanes; i++)
253 		reg |= CSI2TX_DPHY_CFG_LANE_ENABLE(csi2tx->lanes[i] - 1);
254 	writel(reg, csi2tx->base + CSI2TX_DPHY_CFG_REG);
255 
256 	udelay(10);
257 
258 	/* Switch to HS mode */
259 	reg &= ~CSI2TX_DPHY_CFG_MODE_MASK;
260 	writel(reg | CSI2TX_DPHY_CFG_MODE_HS,
261 	       csi2tx->base + CSI2TX_DPHY_CFG_REG);
262 }
263 
264 /* Configures D-PHY in CSIv1.3 */
265 static void csi2tx_dphy_setup(struct csi2tx_priv *csi2tx)
266 {
267 	u32 reg;
268 	unsigned int i;
269 
270 	csi2tx_dphy_set_wakeup(csi2tx);
271 
272 	/* Put our lanes (clock and data) out of reset */
273 	reg = CSI2TX_DPHY_CFG_CLK_RESET | CSI2TX_DPHY_CFG_MODE_LPDT;
274 	for (i = 0; i < csi2tx->num_lanes; i++)
275 		reg |= CSI2TX_DPHY_CFG_LANE_RESET(csi2tx->lanes[i] - 1);
276 	writel(reg, csi2tx->base + CSI2TX_DPHY_CFG_REG);
277 
278 	csi2tx_dphy_init_finish(csi2tx, reg);
279 }
280 
281 /* Configures D-PHY in CSIv2 */
282 static void csi2tx_v2_dphy_setup(struct csi2tx_priv *csi2tx)
283 {
284 	u32 reg;
285 
286 	csi2tx_dphy_set_wakeup(csi2tx);
287 
288 	/* Put our lanes (clock and data) out of reset */
289 	reg = CSI2TX_V2_DPHY_CFG_RESET | CSI2TX_V2_DPHY_CFG_MODE_LPDT;
290 	writel(reg, csi2tx->base + CSI2TX_V2_DPHY_CFG_REG);
291 
292 	csi2tx_dphy_init_finish(csi2tx, reg);
293 }
294 
295 static void csi2tx_reset(struct csi2tx_priv *csi2tx)
296 {
297 	writel(CSI2TX_CONFIG_SRST_REQ, csi2tx->base + CSI2TX_CONFIG_REG);
298 
299 	udelay(10);
300 }
301 
302 static int csi2tx_start(struct csi2tx_priv *csi2tx)
303 {
304 	struct media_entity *entity = &csi2tx->subdev.entity;
305 	struct media_link *link;
306 	unsigned int i;
307 
308 	csi2tx_reset(csi2tx);
309 
310 	writel(CSI2TX_CONFIG_CFG_REQ, csi2tx->base + CSI2TX_CONFIG_REG);
311 
312 	udelay(10);
313 
314 	if (csi2tx->vops && csi2tx->vops->dphy_setup) {
315 		csi2tx->vops->dphy_setup(csi2tx);
316 		udelay(10);
317 	}
318 
319 	/*
320 	 * Create a static mapping between the CSI virtual channels
321 	 * and the input streams.
322 	 *
323 	 * This should be enhanced, but v4l2 lacks the support for
324 	 * changing that mapping dynamically at the moment.
325 	 *
326 	 * We're protected from the userspace setting up links at the
327 	 * same time by the upper layer having called
328 	 * media_pipeline_start().
329 	 */
330 	list_for_each_entry(link, &entity->links, list) {
331 		struct v4l2_mbus_framefmt *mfmt;
332 		const struct csi2tx_fmt *fmt;
333 		unsigned int stream;
334 		int pad_idx = -1;
335 
336 		/* Only consider our enabled input pads */
337 		for (i = CSI2TX_PAD_SINK_STREAM0; i < CSI2TX_PAD_MAX; i++) {
338 			struct media_pad *pad = &csi2tx->pads[i];
339 
340 			if ((pad == link->sink) &&
341 			    (link->flags & MEDIA_LNK_FL_ENABLED)) {
342 				pad_idx = i;
343 				break;
344 			}
345 		}
346 
347 		if (pad_idx < 0)
348 			continue;
349 
350 		mfmt = &csi2tx->pad_fmts[pad_idx];
351 		fmt = csi2tx_get_fmt_from_mbus(mfmt->code);
352 		if (!fmt)
353 			continue;
354 
355 		stream = pad_idx - CSI2TX_PAD_SINK_STREAM0;
356 
357 		/*
358 		 * We use the stream ID there, but it's wrong.
359 		 *
360 		 * A stream could very well send a data type that is
361 		 * not equal to its stream ID. We need to find a
362 		 * proper way to address it.
363 		 */
364 		writel(CSI2TX_DT_CFG_DT(fmt->dt),
365 		       csi2tx->base + CSI2TX_DT_CFG_REG(stream));
366 
367 		writel(CSI2TX_DT_FORMAT_BYTES_PER_LINE(mfmt->width * fmt->bpp) |
368 		       CSI2TX_DT_FORMAT_MAX_LINE_NUM(mfmt->height + 1),
369 		       csi2tx->base + CSI2TX_DT_FORMAT_REG(stream));
370 
371 		/*
372 		 * TODO: This needs to be calculated based on the
373 		 * output CSI2 clock rate.
374 		 */
375 		writel(CSI2TX_STREAM_IF_CFG_FILL_LEVEL(4),
376 		       csi2tx->base + CSI2TX_STREAM_IF_CFG_REG(stream));
377 	}
378 
379 	/* Disable the configuration mode */
380 	writel(0, csi2tx->base + CSI2TX_CONFIG_REG);
381 
382 	return 0;
383 }
384 
385 static void csi2tx_stop(struct csi2tx_priv *csi2tx)
386 {
387 	writel(CSI2TX_CONFIG_CFG_REQ | CSI2TX_CONFIG_SRST_REQ,
388 	       csi2tx->base + CSI2TX_CONFIG_REG);
389 }
390 
391 static int csi2tx_s_stream(struct v4l2_subdev *subdev, int enable)
392 {
393 	struct csi2tx_priv *csi2tx = v4l2_subdev_to_csi2tx(subdev);
394 	int ret = 0;
395 
396 	mutex_lock(&csi2tx->lock);
397 
398 	if (enable) {
399 		/*
400 		 * If we're not the first users, there's no need to
401 		 * enable the whole controller.
402 		 */
403 		if (!csi2tx->count) {
404 			ret = csi2tx_start(csi2tx);
405 			if (ret)
406 				goto out;
407 		}
408 
409 		csi2tx->count++;
410 	} else {
411 		csi2tx->count--;
412 
413 		/*
414 		 * Let the last user turn off the lights.
415 		 */
416 		if (!csi2tx->count)
417 			csi2tx_stop(csi2tx);
418 	}
419 
420 out:
421 	mutex_unlock(&csi2tx->lock);
422 	return ret;
423 }
424 
425 static const struct v4l2_subdev_video_ops csi2tx_video_ops = {
426 	.s_stream	= csi2tx_s_stream,
427 };
428 
429 static const struct v4l2_subdev_ops csi2tx_subdev_ops = {
430 	.pad		= &csi2tx_pad_ops,
431 	.video		= &csi2tx_video_ops,
432 };
433 
434 static int csi2tx_get_resources(struct csi2tx_priv *csi2tx,
435 				struct platform_device *pdev)
436 {
437 	unsigned int i;
438 	u32 dev_cfg;
439 	int ret;
440 
441 	csi2tx->base = devm_platform_ioremap_resource(pdev, 0);
442 	if (IS_ERR(csi2tx->base))
443 		return PTR_ERR(csi2tx->base);
444 
445 	csi2tx->p_clk = devm_clk_get(&pdev->dev, "p_clk");
446 	if (IS_ERR(csi2tx->p_clk)) {
447 		dev_err(&pdev->dev, "Couldn't get p_clk\n");
448 		return PTR_ERR(csi2tx->p_clk);
449 	}
450 
451 	csi2tx->esc_clk = devm_clk_get(&pdev->dev, "esc_clk");
452 	if (IS_ERR(csi2tx->esc_clk)) {
453 		dev_err(&pdev->dev, "Couldn't get the esc_clk\n");
454 		return PTR_ERR(csi2tx->esc_clk);
455 	}
456 
457 	ret = clk_prepare_enable(csi2tx->p_clk);
458 	if (ret) {
459 		dev_err(&pdev->dev, "Couldn't prepare and enable p_clk\n");
460 		return ret;
461 	}
462 
463 	dev_cfg = readl(csi2tx->base + CSI2TX_DEVICE_CONFIG_REG);
464 	clk_disable_unprepare(csi2tx->p_clk);
465 
466 	csi2tx->max_lanes = dev_cfg & CSI2TX_DEVICE_CONFIG_LANES_MASK;
467 	if (csi2tx->max_lanes > CSI2TX_LANES_MAX) {
468 		dev_err(&pdev->dev, "Invalid number of lanes: %u\n",
469 			csi2tx->max_lanes);
470 		return -EINVAL;
471 	}
472 
473 	csi2tx->max_streams = (dev_cfg & CSI2TX_DEVICE_CONFIG_STREAMS_MASK) >> 4;
474 	if (csi2tx->max_streams > CSI2TX_STREAMS_MAX) {
475 		dev_err(&pdev->dev, "Invalid number of streams: %u\n",
476 			csi2tx->max_streams);
477 		return -EINVAL;
478 	}
479 
480 	csi2tx->has_internal_dphy = !!(dev_cfg & CSI2TX_DEVICE_CONFIG_HAS_DPHY);
481 
482 	for (i = 0; i < csi2tx->max_streams; i++) {
483 		char clk_name[16];
484 
485 		snprintf(clk_name, sizeof(clk_name), "pixel_if%u_clk", i);
486 		csi2tx->pixel_clk[i] = devm_clk_get(&pdev->dev, clk_name);
487 		if (IS_ERR(csi2tx->pixel_clk[i])) {
488 			dev_err(&pdev->dev, "Couldn't get clock %s\n",
489 				clk_name);
490 			return PTR_ERR(csi2tx->pixel_clk[i]);
491 		}
492 	}
493 
494 	return 0;
495 }
496 
497 static int csi2tx_check_lanes(struct csi2tx_priv *csi2tx)
498 {
499 	struct v4l2_fwnode_endpoint v4l2_ep = { .bus_type = 0 };
500 	struct device_node *ep;
501 	int ret, i;
502 
503 	ep = of_graph_get_endpoint_by_regs(csi2tx->dev->of_node, 0, 0);
504 	if (!ep)
505 		return -EINVAL;
506 
507 	ret = v4l2_fwnode_endpoint_parse(of_fwnode_handle(ep), &v4l2_ep);
508 	if (ret) {
509 		dev_err(csi2tx->dev, "Could not parse v4l2 endpoint\n");
510 		goto out;
511 	}
512 
513 	if (v4l2_ep.bus_type != V4L2_MBUS_CSI2_DPHY) {
514 		dev_err(csi2tx->dev, "Unsupported media bus type: 0x%x\n",
515 			v4l2_ep.bus_type);
516 		ret = -EINVAL;
517 		goto out;
518 	}
519 
520 	csi2tx->num_lanes = v4l2_ep.bus.mipi_csi2.num_data_lanes;
521 	if (csi2tx->num_lanes > csi2tx->max_lanes) {
522 		dev_err(csi2tx->dev,
523 			"Current configuration uses more lanes than supported\n");
524 		ret = -EINVAL;
525 		goto out;
526 	}
527 
528 	for (i = 0; i < csi2tx->num_lanes; i++) {
529 		if (v4l2_ep.bus.mipi_csi2.data_lanes[i] < 1) {
530 			dev_err(csi2tx->dev, "Invalid lane[%d] number: %u\n",
531 				i, v4l2_ep.bus.mipi_csi2.data_lanes[i]);
532 			ret = -EINVAL;
533 			goto out;
534 		}
535 	}
536 
537 	memcpy(csi2tx->lanes, v4l2_ep.bus.mipi_csi2.data_lanes,
538 	       sizeof(csi2tx->lanes));
539 
540 out:
541 	of_node_put(ep);
542 	return ret;
543 }
544 
545 static const struct csi2tx_vops csi2tx_vops = {
546 	.dphy_setup = csi2tx_dphy_setup,
547 };
548 
549 static const struct csi2tx_vops csi2tx_v2_vops = {
550 	.dphy_setup = csi2tx_v2_dphy_setup,
551 };
552 
553 static const struct of_device_id csi2tx_of_table[] = {
554 	{
555 		.compatible = "cdns,csi2tx",
556 		.data = &csi2tx_vops
557 	},
558 	{
559 		.compatible = "cdns,csi2tx-1.3",
560 		.data = &csi2tx_vops
561 	},
562 	{
563 		.compatible = "cdns,csi2tx-2.1",
564 		.data = &csi2tx_v2_vops
565 	},
566 	{ }
567 };
568 MODULE_DEVICE_TABLE(of, csi2tx_of_table);
569 
570 static int csi2tx_probe(struct platform_device *pdev)
571 {
572 	struct csi2tx_priv *csi2tx;
573 	const struct of_device_id *of_id;
574 	unsigned int i;
575 	int ret;
576 
577 	csi2tx = kzalloc(sizeof(*csi2tx), GFP_KERNEL);
578 	if (!csi2tx)
579 		return -ENOMEM;
580 	platform_set_drvdata(pdev, csi2tx);
581 	mutex_init(&csi2tx->lock);
582 	csi2tx->dev = &pdev->dev;
583 
584 	ret = csi2tx_get_resources(csi2tx, pdev);
585 	if (ret)
586 		goto err_free_priv;
587 
588 	of_id = of_match_node(csi2tx_of_table, pdev->dev.of_node);
589 	csi2tx->vops = (struct csi2tx_vops *)of_id->data;
590 
591 	v4l2_subdev_init(&csi2tx->subdev, &csi2tx_subdev_ops);
592 	csi2tx->subdev.owner = THIS_MODULE;
593 	csi2tx->subdev.dev = &pdev->dev;
594 	csi2tx->subdev.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
595 	snprintf(csi2tx->subdev.name, V4L2_SUBDEV_NAME_SIZE, "%s.%s",
596 		 KBUILD_MODNAME, dev_name(&pdev->dev));
597 
598 	ret = csi2tx_check_lanes(csi2tx);
599 	if (ret)
600 		goto err_free_priv;
601 
602 	/* Create our media pads */
603 	csi2tx->subdev.entity.function = MEDIA_ENT_F_VID_IF_BRIDGE;
604 	csi2tx->pads[CSI2TX_PAD_SOURCE].flags = MEDIA_PAD_FL_SOURCE;
605 	for (i = CSI2TX_PAD_SINK_STREAM0; i < CSI2TX_PAD_MAX; i++)
606 		csi2tx->pads[i].flags = MEDIA_PAD_FL_SINK;
607 
608 	/*
609 	 * Only the input pads are considered to have a format at the
610 	 * moment. The CSI link can multiplex various streams with
611 	 * different formats, and we can't expose this in v4l2 right
612 	 * now.
613 	 */
614 	for (i = CSI2TX_PAD_SINK_STREAM0; i < CSI2TX_PAD_MAX; i++)
615 		csi2tx->pad_fmts[i] = fmt_default;
616 
617 	ret = media_entity_pads_init(&csi2tx->subdev.entity, CSI2TX_PAD_MAX,
618 				     csi2tx->pads);
619 	if (ret)
620 		goto err_free_priv;
621 
622 	ret = v4l2_async_register_subdev(&csi2tx->subdev);
623 	if (ret < 0)
624 		goto err_free_priv;
625 
626 	dev_info(&pdev->dev,
627 		 "Probed CSI2TX with %u/%u lanes, %u streams, %s D-PHY\n",
628 		 csi2tx->num_lanes, csi2tx->max_lanes, csi2tx->max_streams,
629 		 csi2tx->has_internal_dphy ? "internal" : "no");
630 
631 	return 0;
632 
633 err_free_priv:
634 	kfree(csi2tx);
635 	return ret;
636 }
637 
638 static int csi2tx_remove(struct platform_device *pdev)
639 {
640 	struct csi2tx_priv *csi2tx = platform_get_drvdata(pdev);
641 
642 	v4l2_async_unregister_subdev(&csi2tx->subdev);
643 	kfree(csi2tx);
644 
645 	return 0;
646 }
647 
648 static struct platform_driver csi2tx_driver = {
649 	.probe	= csi2tx_probe,
650 	.remove	= csi2tx_remove,
651 
652 	.driver	= {
653 		.name		= "cdns-csi2tx",
654 		.of_match_table	= csi2tx_of_table,
655 	},
656 };
657 module_platform_driver(csi2tx_driver);
658 MODULE_AUTHOR("Maxime Ripard <maxime.ripard@bootlin.com>");
659 MODULE_DESCRIPTION("Cadence CSI2-TX controller");
660 MODULE_LICENSE("GPL");
661