xref: /linux/drivers/media/platform/cadence/cdns-csi2rx.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Driver for Cadence MIPI-CSI2 RX Controller v1.3
4  *
5  * Copyright (C) 2017 Cadence Design Systems Inc.
6  */
7 
8 #include <linux/clk.h>
9 #include <linux/delay.h>
10 #include <linux/io.h>
11 #include <linux/iopoll.h>
12 #include <linux/module.h>
13 #include <linux/of.h>
14 #include <linux/of_graph.h>
15 #include <linux/phy/phy.h>
16 #include <linux/platform_device.h>
17 #include <linux/reset.h>
18 #include <linux/slab.h>
19 
20 #include <media/v4l2-ctrls.h>
21 #include <media/v4l2-device.h>
22 #include <media/v4l2-fwnode.h>
23 #include <media/v4l2-subdev.h>
24 
25 #define CSI2RX_DEVICE_CFG_REG			0x000
26 
27 #define CSI2RX_SOFT_RESET_REG			0x004
28 #define CSI2RX_SOFT_RESET_PROTOCOL			BIT(1)
29 #define CSI2RX_SOFT_RESET_FRONT				BIT(0)
30 
31 #define CSI2RX_STATIC_CFG_REG			0x008
32 #define CSI2RX_STATIC_CFG_DLANE_MAP(llane, plane)	((plane) << (16 + (llane) * 4))
33 #define CSI2RX_STATIC_CFG_LANES_MASK			GENMASK(11, 8)
34 
35 #define CSI2RX_DPHY_LANE_CTRL_REG		0x40
36 #define CSI2RX_DPHY_CL_RST			BIT(16)
37 #define CSI2RX_DPHY_DL_RST(i)			BIT((i) + 12)
38 #define CSI2RX_DPHY_CL_EN			BIT(4)
39 #define CSI2RX_DPHY_DL_EN(i)			BIT(i)
40 
41 #define CSI2RX_STREAM_BASE(n)		(((n) + 1) * 0x100)
42 
43 #define CSI2RX_STREAM_CTRL_REG(n)		(CSI2RX_STREAM_BASE(n) + 0x000)
44 #define CSI2RX_STREAM_CTRL_SOFT_RST			BIT(4)
45 #define CSI2RX_STREAM_CTRL_STOP				BIT(1)
46 #define CSI2RX_STREAM_CTRL_START			BIT(0)
47 
48 #define CSI2RX_STREAM_STATUS_REG(n)		(CSI2RX_STREAM_BASE(n) + 0x004)
49 #define CSI2RX_STREAM_STATUS_RDY			BIT(31)
50 
51 #define CSI2RX_STREAM_DATA_CFG_REG(n)		(CSI2RX_STREAM_BASE(n) + 0x008)
52 #define CSI2RX_STREAM_DATA_CFG_VC_SELECT(n)		BIT((n) + 16)
53 
54 #define CSI2RX_STREAM_CFG_REG(n)		(CSI2RX_STREAM_BASE(n) + 0x00c)
55 #define CSI2RX_STREAM_CFG_FIFO_MODE_LARGE_BUF		(1 << 8)
56 
57 #define CSI2RX_LANES_MAX	4
58 #define CSI2RX_STREAMS_MAX	4
59 
60 enum csi2rx_pads {
61 	CSI2RX_PAD_SINK,
62 	CSI2RX_PAD_SOURCE_STREAM0,
63 	CSI2RX_PAD_SOURCE_STREAM1,
64 	CSI2RX_PAD_SOURCE_STREAM2,
65 	CSI2RX_PAD_SOURCE_STREAM3,
66 	CSI2RX_PAD_MAX,
67 };
68 
69 struct csi2rx_fmt {
70 	u32				code;
71 	u8				bpp;
72 };
73 
74 struct csi2rx_priv {
75 	struct device			*dev;
76 	unsigned int			count;
77 
78 	/*
79 	 * Used to prevent race conditions between multiple,
80 	 * concurrent calls to start and stop.
81 	 */
82 	struct mutex			lock;
83 
84 	void __iomem			*base;
85 	struct clk			*sys_clk;
86 	struct clk			*p_clk;
87 	struct clk			*pixel_clk[CSI2RX_STREAMS_MAX];
88 	struct reset_control		*sys_rst;
89 	struct reset_control		*p_rst;
90 	struct reset_control		*pixel_rst[CSI2RX_STREAMS_MAX];
91 	struct phy			*dphy;
92 
93 	u8				lanes[CSI2RX_LANES_MAX];
94 	u8				num_lanes;
95 	u8				max_lanes;
96 	u8				max_streams;
97 	bool				has_internal_dphy;
98 
99 	struct v4l2_subdev		subdev;
100 	struct v4l2_async_notifier	notifier;
101 	struct media_pad		pads[CSI2RX_PAD_MAX];
102 
103 	/* Remote source */
104 	struct v4l2_subdev		*source_subdev;
105 	int				source_pad;
106 };
107 
108 static const struct csi2rx_fmt formats[] = {
109 	{ .code	= MEDIA_BUS_FMT_YUYV8_1X16, .bpp = 16, },
110 	{ .code	= MEDIA_BUS_FMT_UYVY8_1X16, .bpp = 16, },
111 	{ .code	= MEDIA_BUS_FMT_YVYU8_1X16, .bpp = 16, },
112 	{ .code	= MEDIA_BUS_FMT_VYUY8_1X16, .bpp = 16, },
113 	{ .code	= MEDIA_BUS_FMT_SBGGR8_1X8, .bpp = 8, },
114 	{ .code	= MEDIA_BUS_FMT_SGBRG8_1X8, .bpp = 8, },
115 	{ .code	= MEDIA_BUS_FMT_SGRBG8_1X8, .bpp = 8, },
116 	{ .code	= MEDIA_BUS_FMT_SRGGB8_1X8, .bpp = 8, },
117 	{ .code	= MEDIA_BUS_FMT_Y8_1X8,     .bpp = 8, },
118 	{ .code	= MEDIA_BUS_FMT_SBGGR10_1X10, .bpp = 10, },
119 	{ .code	= MEDIA_BUS_FMT_SGBRG10_1X10, .bpp = 10, },
120 	{ .code	= MEDIA_BUS_FMT_SGRBG10_1X10, .bpp = 10, },
121 	{ .code	= MEDIA_BUS_FMT_SRGGB10_1X10, .bpp = 10, },
122 	{ .code	= MEDIA_BUS_FMT_RGB565_1X16,  .bpp = 16, },
123 	{ .code	= MEDIA_BUS_FMT_RGB888_1X24,  .bpp = 24, },
124 	{ .code	= MEDIA_BUS_FMT_BGR888_1X24,  .bpp = 24, },
125 };
126 
127 static const struct csi2rx_fmt *csi2rx_get_fmt_by_code(u32 code)
128 {
129 	unsigned int i;
130 
131 	for (i = 0; i < ARRAY_SIZE(formats); i++)
132 		if (formats[i].code == code)
133 			return &formats[i];
134 
135 	return NULL;
136 }
137 
138 static inline
139 struct csi2rx_priv *v4l2_subdev_to_csi2rx(struct v4l2_subdev *subdev)
140 {
141 	return container_of(subdev, struct csi2rx_priv, subdev);
142 }
143 
144 static void csi2rx_reset(struct csi2rx_priv *csi2rx)
145 {
146 	unsigned int i;
147 
148 	/* Reset module */
149 	writel(CSI2RX_SOFT_RESET_PROTOCOL | CSI2RX_SOFT_RESET_FRONT,
150 	       csi2rx->base + CSI2RX_SOFT_RESET_REG);
151 	/* Reset individual streams. */
152 	for (i = 0; i < csi2rx->max_streams; i++) {
153 		writel(CSI2RX_STREAM_CTRL_SOFT_RST,
154 		       csi2rx->base + CSI2RX_STREAM_CTRL_REG(i));
155 	}
156 
157 	usleep_range(10, 20);
158 
159 	/* Clear resets */
160 	writel(0, csi2rx->base + CSI2RX_SOFT_RESET_REG);
161 	for (i = 0; i < csi2rx->max_streams; i++)
162 		writel(0, csi2rx->base + CSI2RX_STREAM_CTRL_REG(i));
163 }
164 
165 static int csi2rx_configure_ext_dphy(struct csi2rx_priv *csi2rx)
166 {
167 	union phy_configure_opts opts = { };
168 	struct phy_configure_opts_mipi_dphy *cfg = &opts.mipi_dphy;
169 	struct v4l2_subdev_format sd_fmt = {
170 		.which	= V4L2_SUBDEV_FORMAT_ACTIVE,
171 		.pad	= CSI2RX_PAD_SINK,
172 	};
173 	const struct csi2rx_fmt *fmt;
174 	s64 link_freq;
175 	int ret;
176 
177 	ret = v4l2_subdev_call_state_active(&csi2rx->subdev, pad, get_fmt,
178 					    &sd_fmt);
179 	if (ret < 0)
180 		return ret;
181 
182 	fmt = csi2rx_get_fmt_by_code(sd_fmt.format.code);
183 
184 	link_freq = v4l2_get_link_freq(csi2rx->source_subdev->ctrl_handler,
185 				       fmt->bpp, 2 * csi2rx->num_lanes);
186 	if (link_freq < 0)
187 		return link_freq;
188 
189 	ret = phy_mipi_dphy_get_default_config_for_hsclk(link_freq,
190 							 csi2rx->num_lanes, cfg);
191 	if (ret)
192 		return ret;
193 
194 	ret = phy_power_on(csi2rx->dphy);
195 	if (ret)
196 		return ret;
197 
198 	ret = phy_configure(csi2rx->dphy, &opts);
199 	if (ret) {
200 		phy_power_off(csi2rx->dphy);
201 		return ret;
202 	}
203 
204 	return 0;
205 }
206 
207 static int csi2rx_start(struct csi2rx_priv *csi2rx)
208 {
209 	unsigned int i;
210 	unsigned long lanes_used = 0;
211 	u32 reg;
212 	int ret;
213 
214 	ret = clk_prepare_enable(csi2rx->p_clk);
215 	if (ret)
216 		return ret;
217 
218 	reset_control_deassert(csi2rx->p_rst);
219 	csi2rx_reset(csi2rx);
220 
221 	reg = csi2rx->num_lanes << 8;
222 	for (i = 0; i < csi2rx->num_lanes; i++) {
223 		reg |= CSI2RX_STATIC_CFG_DLANE_MAP(i, csi2rx->lanes[i]);
224 		set_bit(csi2rx->lanes[i], &lanes_used);
225 	}
226 
227 	/*
228 	 * Even the unused lanes need to be mapped. In order to avoid
229 	 * to map twice to the same physical lane, keep the lanes used
230 	 * in the previous loop, and only map unused physical lanes to
231 	 * the rest of our logical lanes.
232 	 */
233 	for (i = csi2rx->num_lanes; i < csi2rx->max_lanes; i++) {
234 		unsigned int idx = find_first_zero_bit(&lanes_used,
235 						       csi2rx->max_lanes);
236 		set_bit(idx, &lanes_used);
237 		reg |= CSI2RX_STATIC_CFG_DLANE_MAP(i, i + 1);
238 	}
239 
240 	writel(reg, csi2rx->base + CSI2RX_STATIC_CFG_REG);
241 
242 	/* Enable DPHY clk and data lanes. */
243 	if (csi2rx->dphy) {
244 		reg = CSI2RX_DPHY_CL_EN | CSI2RX_DPHY_CL_RST;
245 		for (i = 0; i < csi2rx->num_lanes; i++) {
246 			reg |= CSI2RX_DPHY_DL_EN(csi2rx->lanes[i] - 1);
247 			reg |= CSI2RX_DPHY_DL_RST(csi2rx->lanes[i] - 1);
248 		}
249 
250 		writel(reg, csi2rx->base + CSI2RX_DPHY_LANE_CTRL_REG);
251 
252 		ret = csi2rx_configure_ext_dphy(csi2rx);
253 		if (ret) {
254 			dev_err(csi2rx->dev,
255 				"Failed to configure external DPHY: %d\n", ret);
256 			goto err_disable_pclk;
257 		}
258 	}
259 
260 	/*
261 	 * Create a static mapping between the CSI virtual channels
262 	 * and the output stream.
263 	 *
264 	 * This should be enhanced, but v4l2 lacks the support for
265 	 * changing that mapping dynamically.
266 	 *
267 	 * We also cannot enable and disable independent streams here,
268 	 * hence the reference counting.
269 	 */
270 	for (i = 0; i < csi2rx->max_streams; i++) {
271 		ret = clk_prepare_enable(csi2rx->pixel_clk[i]);
272 		if (ret)
273 			goto err_disable_pixclk;
274 
275 		reset_control_deassert(csi2rx->pixel_rst[i]);
276 
277 		writel(CSI2RX_STREAM_CFG_FIFO_MODE_LARGE_BUF,
278 		       csi2rx->base + CSI2RX_STREAM_CFG_REG(i));
279 
280 		/*
281 		 * Enable one virtual channel. When multiple virtual channels
282 		 * are supported this will have to be changed.
283 		 */
284 		writel(CSI2RX_STREAM_DATA_CFG_VC_SELECT(0),
285 		       csi2rx->base + CSI2RX_STREAM_DATA_CFG_REG(i));
286 
287 		writel(CSI2RX_STREAM_CTRL_START,
288 		       csi2rx->base + CSI2RX_STREAM_CTRL_REG(i));
289 	}
290 
291 	ret = clk_prepare_enable(csi2rx->sys_clk);
292 	if (ret)
293 		goto err_disable_pixclk;
294 
295 	reset_control_deassert(csi2rx->sys_rst);
296 
297 	ret = v4l2_subdev_call(csi2rx->source_subdev, video, s_stream, true);
298 	if (ret)
299 		goto err_disable_sysclk;
300 
301 	clk_disable_unprepare(csi2rx->p_clk);
302 
303 	return 0;
304 
305 err_disable_sysclk:
306 	clk_disable_unprepare(csi2rx->sys_clk);
307 err_disable_pixclk:
308 	for (; i > 0; i--) {
309 		reset_control_assert(csi2rx->pixel_rst[i - 1]);
310 		clk_disable_unprepare(csi2rx->pixel_clk[i - 1]);
311 	}
312 
313 	if (csi2rx->dphy) {
314 		writel(0, csi2rx->base + CSI2RX_DPHY_LANE_CTRL_REG);
315 		phy_power_off(csi2rx->dphy);
316 	}
317 err_disable_pclk:
318 	clk_disable_unprepare(csi2rx->p_clk);
319 
320 	return ret;
321 }
322 
323 static void csi2rx_stop(struct csi2rx_priv *csi2rx)
324 {
325 	unsigned int i;
326 	u32 val;
327 	int ret;
328 
329 	clk_prepare_enable(csi2rx->p_clk);
330 	reset_control_assert(csi2rx->sys_rst);
331 	clk_disable_unprepare(csi2rx->sys_clk);
332 
333 	for (i = 0; i < csi2rx->max_streams; i++) {
334 		writel(CSI2RX_STREAM_CTRL_STOP,
335 		       csi2rx->base + CSI2RX_STREAM_CTRL_REG(i));
336 
337 		ret = readl_relaxed_poll_timeout(csi2rx->base +
338 						 CSI2RX_STREAM_STATUS_REG(i),
339 						 val,
340 						 !(val & CSI2RX_STREAM_STATUS_RDY),
341 						 10, 10000);
342 		if (ret)
343 			dev_warn(csi2rx->dev,
344 				 "Failed to stop streaming on pad%u\n", i);
345 
346 		reset_control_assert(csi2rx->pixel_rst[i]);
347 		clk_disable_unprepare(csi2rx->pixel_clk[i]);
348 	}
349 
350 	reset_control_assert(csi2rx->p_rst);
351 	clk_disable_unprepare(csi2rx->p_clk);
352 
353 	if (v4l2_subdev_call(csi2rx->source_subdev, video, s_stream, false))
354 		dev_warn(csi2rx->dev, "Couldn't disable our subdev\n");
355 
356 	if (csi2rx->dphy) {
357 		writel(0, csi2rx->base + CSI2RX_DPHY_LANE_CTRL_REG);
358 
359 		if (phy_power_off(csi2rx->dphy))
360 			dev_warn(csi2rx->dev, "Couldn't power off DPHY\n");
361 	}
362 }
363 
364 static int csi2rx_s_stream(struct v4l2_subdev *subdev, int enable)
365 {
366 	struct csi2rx_priv *csi2rx = v4l2_subdev_to_csi2rx(subdev);
367 	int ret = 0;
368 
369 	mutex_lock(&csi2rx->lock);
370 
371 	if (enable) {
372 		/*
373 		 * If we're not the first users, there's no need to
374 		 * enable the whole controller.
375 		 */
376 		if (!csi2rx->count) {
377 			ret = csi2rx_start(csi2rx);
378 			if (ret)
379 				goto out;
380 		}
381 
382 		csi2rx->count++;
383 	} else {
384 		csi2rx->count--;
385 
386 		/*
387 		 * Let the last user turn off the lights.
388 		 */
389 		if (!csi2rx->count)
390 			csi2rx_stop(csi2rx);
391 	}
392 
393 out:
394 	mutex_unlock(&csi2rx->lock);
395 	return ret;
396 }
397 
398 static int csi2rx_enum_mbus_code(struct v4l2_subdev *subdev,
399 				 struct v4l2_subdev_state *state,
400 				 struct v4l2_subdev_mbus_code_enum *code_enum)
401 {
402 	if (code_enum->index >= ARRAY_SIZE(formats))
403 		return -EINVAL;
404 
405 	code_enum->code = formats[code_enum->index].code;
406 
407 	return 0;
408 }
409 
410 static int csi2rx_set_fmt(struct v4l2_subdev *subdev,
411 			  struct v4l2_subdev_state *state,
412 			  struct v4l2_subdev_format *format)
413 {
414 	struct v4l2_mbus_framefmt *fmt;
415 	unsigned int i;
416 
417 	/* No transcoding, source and sink formats must match. */
418 	if (format->pad != CSI2RX_PAD_SINK)
419 		return v4l2_subdev_get_fmt(subdev, state, format);
420 
421 	if (!csi2rx_get_fmt_by_code(format->format.code))
422 		format->format.code = formats[0].code;
423 
424 	format->format.field = V4L2_FIELD_NONE;
425 
426 	/* Set sink format */
427 	fmt = v4l2_subdev_state_get_format(state, format->pad);
428 	*fmt = format->format;
429 
430 	/* Propagate to source formats */
431 	for (i = CSI2RX_PAD_SOURCE_STREAM0; i < CSI2RX_PAD_MAX; i++) {
432 		fmt = v4l2_subdev_state_get_format(state, i);
433 		*fmt = format->format;
434 	}
435 
436 	return 0;
437 }
438 
439 static int csi2rx_init_state(struct v4l2_subdev *subdev,
440 			     struct v4l2_subdev_state *state)
441 {
442 	struct v4l2_subdev_format format = {
443 		.pad = CSI2RX_PAD_SINK,
444 		.format = {
445 			.width = 640,
446 			.height = 480,
447 			.code = MEDIA_BUS_FMT_UYVY8_1X16,
448 			.field = V4L2_FIELD_NONE,
449 			.colorspace = V4L2_COLORSPACE_SRGB,
450 			.ycbcr_enc = V4L2_YCBCR_ENC_601,
451 			.quantization = V4L2_QUANTIZATION_LIM_RANGE,
452 			.xfer_func = V4L2_XFER_FUNC_SRGB,
453 		},
454 	};
455 
456 	return csi2rx_set_fmt(subdev, state, &format);
457 }
458 
459 static const struct v4l2_subdev_pad_ops csi2rx_pad_ops = {
460 	.enum_mbus_code	= csi2rx_enum_mbus_code,
461 	.get_fmt	= v4l2_subdev_get_fmt,
462 	.set_fmt	= csi2rx_set_fmt,
463 };
464 
465 static const struct v4l2_subdev_video_ops csi2rx_video_ops = {
466 	.s_stream	= csi2rx_s_stream,
467 };
468 
469 static const struct v4l2_subdev_ops csi2rx_subdev_ops = {
470 	.video		= &csi2rx_video_ops,
471 	.pad		= &csi2rx_pad_ops,
472 };
473 
474 static const struct v4l2_subdev_internal_ops csi2rx_internal_ops = {
475 	.init_state	= csi2rx_init_state,
476 };
477 
478 static const struct media_entity_operations csi2rx_media_ops = {
479 	.link_validate = v4l2_subdev_link_validate,
480 };
481 
482 static int csi2rx_async_bound(struct v4l2_async_notifier *notifier,
483 			      struct v4l2_subdev *s_subdev,
484 			      struct v4l2_async_connection *asd)
485 {
486 	struct v4l2_subdev *subdev = notifier->sd;
487 	struct csi2rx_priv *csi2rx = v4l2_subdev_to_csi2rx(subdev);
488 
489 	csi2rx->source_pad = media_entity_get_fwnode_pad(&s_subdev->entity,
490 							 asd->match.fwnode,
491 							 MEDIA_PAD_FL_SOURCE);
492 	if (csi2rx->source_pad < 0) {
493 		dev_err(csi2rx->dev, "Couldn't find output pad for subdev %s\n",
494 			s_subdev->name);
495 		return csi2rx->source_pad;
496 	}
497 
498 	csi2rx->source_subdev = s_subdev;
499 
500 	dev_dbg(csi2rx->dev, "Bound %s pad: %d\n", s_subdev->name,
501 		csi2rx->source_pad);
502 
503 	return media_create_pad_link(&csi2rx->source_subdev->entity,
504 				     csi2rx->source_pad,
505 				     &csi2rx->subdev.entity, 0,
506 				     MEDIA_LNK_FL_ENABLED |
507 				     MEDIA_LNK_FL_IMMUTABLE);
508 }
509 
510 static const struct v4l2_async_notifier_operations csi2rx_notifier_ops = {
511 	.bound		= csi2rx_async_bound,
512 };
513 
514 static int csi2rx_get_resources(struct csi2rx_priv *csi2rx,
515 				struct platform_device *pdev)
516 {
517 	unsigned char i;
518 	u32 dev_cfg;
519 	int ret;
520 
521 	csi2rx->base = devm_platform_ioremap_resource(pdev, 0);
522 	if (IS_ERR(csi2rx->base))
523 		return PTR_ERR(csi2rx->base);
524 
525 	csi2rx->sys_clk = devm_clk_get(&pdev->dev, "sys_clk");
526 	if (IS_ERR(csi2rx->sys_clk)) {
527 		dev_err(&pdev->dev, "Couldn't get sys clock\n");
528 		return PTR_ERR(csi2rx->sys_clk);
529 	}
530 
531 	csi2rx->p_clk = devm_clk_get(&pdev->dev, "p_clk");
532 	if (IS_ERR(csi2rx->p_clk)) {
533 		dev_err(&pdev->dev, "Couldn't get P clock\n");
534 		return PTR_ERR(csi2rx->p_clk);
535 	}
536 
537 	csi2rx->sys_rst = devm_reset_control_get_optional_exclusive(&pdev->dev,
538 								    "sys");
539 	if (IS_ERR(csi2rx->sys_rst))
540 		return PTR_ERR(csi2rx->sys_rst);
541 
542 	csi2rx->p_rst = devm_reset_control_get_optional_exclusive(&pdev->dev,
543 								  "reg_bank");
544 	if (IS_ERR(csi2rx->p_rst))
545 		return PTR_ERR(csi2rx->p_rst);
546 
547 	csi2rx->dphy = devm_phy_optional_get(&pdev->dev, "dphy");
548 	if (IS_ERR(csi2rx->dphy)) {
549 		dev_err(&pdev->dev, "Couldn't get external D-PHY\n");
550 		return PTR_ERR(csi2rx->dphy);
551 	}
552 
553 	ret = clk_prepare_enable(csi2rx->p_clk);
554 	if (ret) {
555 		dev_err(&pdev->dev, "Couldn't prepare and enable P clock\n");
556 		return ret;
557 	}
558 
559 	dev_cfg = readl(csi2rx->base + CSI2RX_DEVICE_CFG_REG);
560 	clk_disable_unprepare(csi2rx->p_clk);
561 
562 	csi2rx->max_lanes = dev_cfg & 7;
563 	if (csi2rx->max_lanes > CSI2RX_LANES_MAX) {
564 		dev_err(&pdev->dev, "Invalid number of lanes: %u\n",
565 			csi2rx->max_lanes);
566 		return -EINVAL;
567 	}
568 
569 	csi2rx->max_streams = (dev_cfg >> 4) & 7;
570 	if (csi2rx->max_streams > CSI2RX_STREAMS_MAX) {
571 		dev_err(&pdev->dev, "Invalid number of streams: %u\n",
572 			csi2rx->max_streams);
573 		return -EINVAL;
574 	}
575 
576 	csi2rx->has_internal_dphy = dev_cfg & BIT(3) ? true : false;
577 
578 	/*
579 	 * FIXME: Once we'll have internal D-PHY support, the check
580 	 * will need to be removed.
581 	 */
582 	if (!csi2rx->dphy && csi2rx->has_internal_dphy) {
583 		dev_err(&pdev->dev, "Internal D-PHY not supported yet\n");
584 		return -EINVAL;
585 	}
586 
587 	for (i = 0; i < csi2rx->max_streams; i++) {
588 		char name[16];
589 
590 		snprintf(name, sizeof(name), "pixel_if%u_clk", i);
591 		csi2rx->pixel_clk[i] = devm_clk_get(&pdev->dev, name);
592 		if (IS_ERR(csi2rx->pixel_clk[i])) {
593 			dev_err(&pdev->dev, "Couldn't get clock %s\n", name);
594 			return PTR_ERR(csi2rx->pixel_clk[i]);
595 		}
596 
597 		snprintf(name, sizeof(name), "pixel_if%u", i);
598 		csi2rx->pixel_rst[i] =
599 			devm_reset_control_get_optional_exclusive(&pdev->dev,
600 								  name);
601 		if (IS_ERR(csi2rx->pixel_rst[i]))
602 			return PTR_ERR(csi2rx->pixel_rst[i]);
603 	}
604 
605 	return 0;
606 }
607 
608 static int csi2rx_parse_dt(struct csi2rx_priv *csi2rx)
609 {
610 	struct v4l2_fwnode_endpoint v4l2_ep = { .bus_type = 0 };
611 	struct v4l2_async_connection *asd;
612 	struct fwnode_handle *fwh;
613 	struct device_node *ep;
614 	int ret;
615 
616 	ep = of_graph_get_endpoint_by_regs(csi2rx->dev->of_node, 0, 0);
617 	if (!ep)
618 		return -EINVAL;
619 
620 	fwh = of_fwnode_handle(ep);
621 	ret = v4l2_fwnode_endpoint_parse(fwh, &v4l2_ep);
622 	if (ret) {
623 		dev_err(csi2rx->dev, "Could not parse v4l2 endpoint\n");
624 		of_node_put(ep);
625 		return ret;
626 	}
627 
628 	if (v4l2_ep.bus_type != V4L2_MBUS_CSI2_DPHY) {
629 		dev_err(csi2rx->dev, "Unsupported media bus type: 0x%x\n",
630 			v4l2_ep.bus_type);
631 		of_node_put(ep);
632 		return -EINVAL;
633 	}
634 
635 	memcpy(csi2rx->lanes, v4l2_ep.bus.mipi_csi2.data_lanes,
636 	       sizeof(csi2rx->lanes));
637 	csi2rx->num_lanes = v4l2_ep.bus.mipi_csi2.num_data_lanes;
638 	if (csi2rx->num_lanes > csi2rx->max_lanes) {
639 		dev_err(csi2rx->dev, "Unsupported number of data-lanes: %d\n",
640 			csi2rx->num_lanes);
641 		of_node_put(ep);
642 		return -EINVAL;
643 	}
644 
645 	v4l2_async_subdev_nf_init(&csi2rx->notifier, &csi2rx->subdev);
646 
647 	asd = v4l2_async_nf_add_fwnode_remote(&csi2rx->notifier, fwh,
648 					      struct v4l2_async_connection);
649 	of_node_put(ep);
650 	if (IS_ERR(asd)) {
651 		v4l2_async_nf_cleanup(&csi2rx->notifier);
652 		return PTR_ERR(asd);
653 	}
654 
655 	csi2rx->notifier.ops = &csi2rx_notifier_ops;
656 
657 	ret = v4l2_async_nf_register(&csi2rx->notifier);
658 	if (ret)
659 		v4l2_async_nf_cleanup(&csi2rx->notifier);
660 
661 	return ret;
662 }
663 
664 static int csi2rx_probe(struct platform_device *pdev)
665 {
666 	struct csi2rx_priv *csi2rx;
667 	unsigned int i;
668 	int ret;
669 
670 	csi2rx = kzalloc(sizeof(*csi2rx), GFP_KERNEL);
671 	if (!csi2rx)
672 		return -ENOMEM;
673 	platform_set_drvdata(pdev, csi2rx);
674 	csi2rx->dev = &pdev->dev;
675 	mutex_init(&csi2rx->lock);
676 
677 	ret = csi2rx_get_resources(csi2rx, pdev);
678 	if (ret)
679 		goto err_free_priv;
680 
681 	ret = csi2rx_parse_dt(csi2rx);
682 	if (ret)
683 		goto err_free_priv;
684 
685 	csi2rx->subdev.owner = THIS_MODULE;
686 	csi2rx->subdev.dev = &pdev->dev;
687 	v4l2_subdev_init(&csi2rx->subdev, &csi2rx_subdev_ops);
688 	csi2rx->subdev.internal_ops = &csi2rx_internal_ops;
689 	v4l2_set_subdevdata(&csi2rx->subdev, &pdev->dev);
690 	snprintf(csi2rx->subdev.name, sizeof(csi2rx->subdev.name),
691 		 "%s.%s", KBUILD_MODNAME, dev_name(&pdev->dev));
692 
693 	/* Create our media pads */
694 	csi2rx->subdev.entity.function = MEDIA_ENT_F_VID_IF_BRIDGE;
695 	csi2rx->pads[CSI2RX_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
696 	for (i = CSI2RX_PAD_SOURCE_STREAM0; i < CSI2RX_PAD_MAX; i++)
697 		csi2rx->pads[i].flags = MEDIA_PAD_FL_SOURCE;
698 	csi2rx->subdev.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
699 	csi2rx->subdev.entity.ops = &csi2rx_media_ops;
700 
701 	ret = media_entity_pads_init(&csi2rx->subdev.entity, CSI2RX_PAD_MAX,
702 				     csi2rx->pads);
703 	if (ret)
704 		goto err_cleanup;
705 
706 	ret = v4l2_subdev_init_finalize(&csi2rx->subdev);
707 	if (ret)
708 		goto err_cleanup;
709 
710 	ret = v4l2_async_register_subdev(&csi2rx->subdev);
711 	if (ret < 0)
712 		goto err_free_state;
713 
714 	dev_info(&pdev->dev,
715 		 "Probed CSI2RX with %u/%u lanes, %u streams, %s D-PHY\n",
716 		 csi2rx->num_lanes, csi2rx->max_lanes, csi2rx->max_streams,
717 		 csi2rx->dphy ? "external" :
718 		 csi2rx->has_internal_dphy ? "internal" : "no");
719 
720 	return 0;
721 
722 err_free_state:
723 	v4l2_subdev_cleanup(&csi2rx->subdev);
724 err_cleanup:
725 	v4l2_async_nf_unregister(&csi2rx->notifier);
726 	v4l2_async_nf_cleanup(&csi2rx->notifier);
727 	media_entity_cleanup(&csi2rx->subdev.entity);
728 err_free_priv:
729 	kfree(csi2rx);
730 	return ret;
731 }
732 
733 static void csi2rx_remove(struct platform_device *pdev)
734 {
735 	struct csi2rx_priv *csi2rx = platform_get_drvdata(pdev);
736 
737 	v4l2_async_nf_unregister(&csi2rx->notifier);
738 	v4l2_async_nf_cleanup(&csi2rx->notifier);
739 	v4l2_async_unregister_subdev(&csi2rx->subdev);
740 	v4l2_subdev_cleanup(&csi2rx->subdev);
741 	media_entity_cleanup(&csi2rx->subdev.entity);
742 	kfree(csi2rx);
743 }
744 
745 static const struct of_device_id csi2rx_of_table[] = {
746 	{ .compatible = "starfive,jh7110-csi2rx" },
747 	{ .compatible = "cdns,csi2rx" },
748 	{ },
749 };
750 MODULE_DEVICE_TABLE(of, csi2rx_of_table);
751 
752 static struct platform_driver csi2rx_driver = {
753 	.probe	= csi2rx_probe,
754 	.remove = csi2rx_remove,
755 
756 	.driver	= {
757 		.name		= "cdns-csi2rx",
758 		.of_match_table	= csi2rx_of_table,
759 	},
760 };
761 module_platform_driver(csi2rx_driver);
762 MODULE_AUTHOR("Maxime Ripard <maxime.ripard@bootlin.com>");
763 MODULE_DESCRIPTION("Cadence CSI2-RX controller");
764 MODULE_LICENSE("GPL");
765