1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Driver for Renesas RZ/G2L MIPI CSI-2 Receiver
4  *
5  * Copyright (C) 2022 Renesas Electronics Corp.
6  */
7 
8 #include <linux/clk.h>
9 #include <linux/delay.h>
10 #include <linux/interrupt.h>
11 #include <linux/io.h>
12 #include <linux/module.h>
13 #include <linux/of.h>
14 #include <linux/of_device.h>
15 #include <linux/of_graph.h>
16 #include <linux/platform_device.h>
17 #include <linux/pm_runtime.h>
18 #include <linux/reset.h>
19 #include <linux/sys_soc.h>
20 #include <linux/units.h>
21 
22 #include <media/v4l2-ctrls.h>
23 #include <media/v4l2-device.h>
24 #include <media/v4l2-fwnode.h>
25 #include <media/v4l2-mc.h>
26 #include <media/v4l2-subdev.h>
27 
28 /* LINK registers */
29 /* Module Configuration Register */
30 #define CSI2nMCG			0x0
31 #define CSI2nMCG_SDLN			GENMASK(11, 8)
32 
33 /* Module Control Register 0 */
34 #define CSI2nMCT0			0x10
35 #define CSI2nMCT0_VDLN(x)		((x) << 0)
36 
37 /* Module Control Register 2 */
38 #define CSI2nMCT2			0x18
39 #define CSI2nMCT2_FRRSKW(x)		((x) << 16)
40 #define CSI2nMCT2_FRRCLK(x)		((x) << 0)
41 
42 /* Module Control Register 3 */
43 #define CSI2nMCT3			0x1c
44 #define CSI2nMCT3_RXEN			BIT(0)
45 
46 /* Reset Control Register */
47 #define CSI2nRTCT			0x28
48 #define CSI2nRTCT_VSRST			BIT(0)
49 
50 /* Reset Status Register */
51 #define CSI2nRTST			0x2c
52 #define CSI2nRTST_VSRSTS		BIT(0)
53 
54 /* Receive Data Type Enable Low Register */
55 #define CSI2nDTEL			0x60
56 
57 /* Receive Data Type Enable High Register */
58 #define CSI2nDTEH			0x64
59 
60 /* DPHY registers */
61 /* D-PHY Control Register 0 */
62 #define CSIDPHYCTRL0			0x400
63 #define CSIDPHYCTRL0_EN_LDO1200		BIT(1)
64 #define CSIDPHYCTRL0_EN_BGR		BIT(0)
65 
66 /* D-PHY Timing Register 0 */
67 #define CSIDPHYTIM0			0x404
68 #define CSIDPHYTIM0_TCLK_MISS(x)	((x) << 24)
69 #define CSIDPHYTIM0_T_INIT(x)		((x) << 0)
70 
71 /* D-PHY Timing Register 1 */
72 #define CSIDPHYTIM1			0x408
73 #define CSIDPHYTIM1_THS_PREPARE(x)	((x) << 24)
74 #define CSIDPHYTIM1_TCLK_PREPARE(x)	((x) << 16)
75 #define CSIDPHYTIM1_THS_SETTLE(x)	((x) << 8)
76 #define CSIDPHYTIM1_TCLK_SETTLE(x)	((x) << 0)
77 
78 /* D-PHY Skew Adjustment Function */
79 #define CSIDPHYSKW0			0x460
80 #define CSIDPHYSKW0_UTIL_DL0_SKW_ADJ(x)	((x) & 0x3)
81 #define CSIDPHYSKW0_UTIL_DL1_SKW_ADJ(x)	(((x) & 0x3) << 4)
82 #define CSIDPHYSKW0_UTIL_DL2_SKW_ADJ(x)	(((x) & 0x3) << 8)
83 #define CSIDPHYSKW0_UTIL_DL3_SKW_ADJ(x)	(((x) & 0x3) << 12)
84 #define CSIDPHYSKW0_DEFAULT_SKW		CSIDPHYSKW0_UTIL_DL0_SKW_ADJ(1) | \
85 					CSIDPHYSKW0_UTIL_DL1_SKW_ADJ(1) | \
86 					CSIDPHYSKW0_UTIL_DL2_SKW_ADJ(1) | \
87 					CSIDPHYSKW0_UTIL_DL3_SKW_ADJ(1)
88 
89 #define VSRSTS_RETRIES			20
90 
91 #define RZG2L_CSI2_MIN_WIDTH		320
92 #define RZG2L_CSI2_MIN_HEIGHT		240
93 #define RZG2L_CSI2_MAX_WIDTH		2800
94 #define RZG2L_CSI2_MAX_HEIGHT		4095
95 
96 #define RZG2L_CSI2_DEFAULT_WIDTH	RZG2L_CSI2_MIN_WIDTH
97 #define RZG2L_CSI2_DEFAULT_HEIGHT	RZG2L_CSI2_MIN_HEIGHT
98 #define RZG2L_CSI2_DEFAULT_FMT		MEDIA_BUS_FMT_UYVY8_1X16
99 
100 enum rzg2l_csi2_pads {
101 	RZG2L_CSI2_SINK = 0,
102 	RZG2L_CSI2_SOURCE,
103 	NR_OF_RZG2L_CSI2_PAD,
104 };
105 
106 struct rzg2l_csi2 {
107 	struct device *dev;
108 	void __iomem *base;
109 	struct reset_control *presetn;
110 	struct reset_control *cmn_rstb;
111 	struct clk *sysclk;
112 	unsigned long vclk_rate;
113 
114 	struct v4l2_subdev subdev;
115 	struct media_pad pads[NR_OF_RZG2L_CSI2_PAD];
116 
117 	struct v4l2_async_notifier notifier;
118 	struct v4l2_subdev *remote_source;
119 
120 	unsigned short lanes;
121 	unsigned long hsfreq;
122 
123 	bool dphy_enabled;
124 };
125 
126 struct rzg2l_csi2_timings {
127 	u32 t_init;
128 	u32 tclk_miss;
129 	u32 tclk_settle;
130 	u32 ths_settle;
131 	u32 tclk_prepare;
132 	u32 ths_prepare;
133 	u32 max_hsfreq;
134 };
135 
136 static const struct rzg2l_csi2_timings rzg2l_csi2_global_timings[] = {
137 	{
138 		.max_hsfreq = 80,
139 		.t_init = 79801,
140 		.tclk_miss = 4,
141 		.tclk_settle = 23,
142 		.ths_settle = 31,
143 		.tclk_prepare = 10,
144 		.ths_prepare = 19,
145 	},
146 	{
147 		.max_hsfreq = 125,
148 		.t_init = 79801,
149 		.tclk_miss = 4,
150 		.tclk_settle = 23,
151 		.ths_settle = 28,
152 		.tclk_prepare = 10,
153 		.ths_prepare = 19,
154 	},
155 	{
156 		.max_hsfreq = 250,
157 		.t_init = 79801,
158 		.tclk_miss = 4,
159 		.tclk_settle = 23,
160 		.ths_settle = 22,
161 		.tclk_prepare = 10,
162 		.ths_prepare = 16,
163 	},
164 	{
165 		.max_hsfreq = 360,
166 		.t_init = 79801,
167 		.tclk_miss = 4,
168 		.tclk_settle = 18,
169 		.ths_settle = 19,
170 		.tclk_prepare = 10,
171 		.ths_prepare = 10,
172 	},
173 	{
174 		.max_hsfreq = 1500,
175 		.t_init = 79801,
176 		.tclk_miss = 4,
177 		.tclk_settle = 18,
178 		.ths_settle = 18,
179 		.tclk_prepare = 10,
180 		.ths_prepare = 10,
181 	},
182 };
183 
184 struct rzg2l_csi2_format {
185 	u32 code;
186 	unsigned int datatype;
187 	unsigned int bpp;
188 };
189 
190 static const struct rzg2l_csi2_format rzg2l_csi2_formats[] = {
191 	{ .code = MEDIA_BUS_FMT_UYVY8_1X16,	.datatype = 0x1e, .bpp = 16 },
192 };
193 
194 static inline struct rzg2l_csi2 *sd_to_csi2(struct v4l2_subdev *sd)
195 {
196 	return container_of(sd, struct rzg2l_csi2, subdev);
197 }
198 
199 static const struct rzg2l_csi2_format *rzg2l_csi2_code_to_fmt(unsigned int code)
200 {
201 	unsigned int i;
202 
203 	for (i = 0; i < ARRAY_SIZE(rzg2l_csi2_formats); i++)
204 		if (rzg2l_csi2_formats[i].code == code)
205 			return &rzg2l_csi2_formats[i];
206 
207 	return NULL;
208 }
209 
210 static inline struct rzg2l_csi2 *notifier_to_csi2(struct v4l2_async_notifier *n)
211 {
212 	return container_of(n, struct rzg2l_csi2, notifier);
213 }
214 
215 static u32 rzg2l_csi2_read(struct rzg2l_csi2 *csi2, unsigned int reg)
216 {
217 	return ioread32(csi2->base + reg);
218 }
219 
220 static void rzg2l_csi2_write(struct rzg2l_csi2 *csi2, unsigned int reg,
221 			     u32 data)
222 {
223 	iowrite32(data, csi2->base + reg);
224 }
225 
226 static void rzg2l_csi2_set(struct rzg2l_csi2 *csi2, unsigned int reg, u32 set)
227 {
228 	rzg2l_csi2_write(csi2, reg, rzg2l_csi2_read(csi2, reg) | set);
229 }
230 
231 static void rzg2l_csi2_clr(struct rzg2l_csi2 *csi2, unsigned int reg, u32 clr)
232 {
233 	rzg2l_csi2_write(csi2, reg, rzg2l_csi2_read(csi2, reg) & ~clr);
234 }
235 
236 static int rzg2l_csi2_calc_mbps(struct rzg2l_csi2 *csi2)
237 {
238 	struct v4l2_subdev *source = csi2->remote_source;
239 	const struct rzg2l_csi2_format *format;
240 	const struct v4l2_mbus_framefmt *fmt;
241 	struct v4l2_subdev_state *state;
242 	struct v4l2_ctrl *ctrl;
243 	u64 mbps;
244 
245 	/* Read the pixel rate control from remote. */
246 	ctrl = v4l2_ctrl_find(source->ctrl_handler, V4L2_CID_PIXEL_RATE);
247 	if (!ctrl) {
248 		dev_err(csi2->dev, "no pixel rate control in subdev %s\n",
249 			source->name);
250 		return -EINVAL;
251 	}
252 
253 	state = v4l2_subdev_lock_and_get_active_state(&csi2->subdev);
254 	fmt = v4l2_subdev_get_pad_format(&csi2->subdev, state, RZG2L_CSI2_SINK);
255 	format = rzg2l_csi2_code_to_fmt(fmt->code);
256 	v4l2_subdev_unlock_state(state);
257 
258 	/*
259 	 * Calculate hsfreq in Mbps
260 	 * hsfreq = (pixel_rate * bits_per_sample) / number_of_lanes
261 	 */
262 	mbps = v4l2_ctrl_g_ctrl_int64(ctrl) * format->bpp;
263 	do_div(mbps, csi2->lanes * 1000000);
264 
265 	return mbps;
266 }
267 
268 /* -----------------------------------------------------------------------------
269  * DPHY setting
270  */
271 
272 static int rzg2l_csi2_dphy_disable(struct rzg2l_csi2 *csi2)
273 {
274 	int ret;
275 
276 	/* Reset the CRU (D-PHY) */
277 	ret = reset_control_assert(csi2->cmn_rstb);
278 	if (ret)
279 		return ret;
280 
281 	/* Stop the D-PHY clock */
282 	clk_disable_unprepare(csi2->sysclk);
283 
284 	/* Cancel the EN_LDO1200 register setting */
285 	rzg2l_csi2_clr(csi2, CSIDPHYCTRL0, CSIDPHYCTRL0_EN_LDO1200);
286 
287 	/* Cancel the EN_BGR register setting */
288 	rzg2l_csi2_clr(csi2, CSIDPHYCTRL0, CSIDPHYCTRL0_EN_BGR);
289 
290 	csi2->dphy_enabled = false;
291 
292 	return 0;
293 }
294 
295 static int rzg2l_csi2_dphy_enable(struct rzg2l_csi2 *csi2)
296 {
297 	const struct rzg2l_csi2_timings *dphy_timing;
298 	u32 dphytim0, dphytim1;
299 	unsigned int i;
300 	int mbps;
301 	int ret;
302 
303 	mbps = rzg2l_csi2_calc_mbps(csi2);
304 	if (mbps < 0)
305 		return mbps;
306 
307 	csi2->hsfreq = mbps;
308 
309 	/* Set DPHY timing parameters */
310 	for (i = 0; i < ARRAY_SIZE(rzg2l_csi2_global_timings); ++i) {
311 		dphy_timing = &rzg2l_csi2_global_timings[i];
312 
313 		if (csi2->hsfreq <= dphy_timing->max_hsfreq)
314 			break;
315 	}
316 
317 	if (i >= ARRAY_SIZE(rzg2l_csi2_global_timings))
318 		return -EINVAL;
319 
320 	/* Set D-PHY timing parameters */
321 	dphytim0 = CSIDPHYTIM0_TCLK_MISS(dphy_timing->tclk_miss) |
322 			CSIDPHYTIM0_T_INIT(dphy_timing->t_init);
323 	dphytim1 = CSIDPHYTIM1_THS_PREPARE(dphy_timing->ths_prepare) |
324 			CSIDPHYTIM1_TCLK_PREPARE(dphy_timing->tclk_prepare) |
325 			CSIDPHYTIM1_THS_SETTLE(dphy_timing->ths_settle) |
326 			CSIDPHYTIM1_TCLK_SETTLE(dphy_timing->tclk_settle);
327 	rzg2l_csi2_write(csi2, CSIDPHYTIM0, dphytim0);
328 	rzg2l_csi2_write(csi2, CSIDPHYTIM1, dphytim1);
329 
330 	/* Enable D-PHY power control 0 */
331 	rzg2l_csi2_write(csi2, CSIDPHYSKW0, CSIDPHYSKW0_DEFAULT_SKW);
332 
333 	/* Set the EN_BGR bit */
334 	rzg2l_csi2_set(csi2, CSIDPHYCTRL0, CSIDPHYCTRL0_EN_BGR);
335 
336 	/* Delay 20us to be stable */
337 	usleep_range(20, 40);
338 
339 	/* Enable D-PHY power control 1 */
340 	rzg2l_csi2_set(csi2, CSIDPHYCTRL0, CSIDPHYCTRL0_EN_LDO1200);
341 
342 	/* Delay 10us to be stable */
343 	usleep_range(10, 20);
344 
345 	/* Start supplying the internal clock for the D-PHY block */
346 	ret = clk_prepare_enable(csi2->sysclk);
347 	if (ret)
348 		rzg2l_csi2_dphy_disable(csi2);
349 
350 	csi2->dphy_enabled = true;
351 
352 	return ret;
353 }
354 
355 static int rzg2l_csi2_dphy_setting(struct v4l2_subdev *sd, bool on)
356 {
357 	struct rzg2l_csi2 *csi2 = sd_to_csi2(sd);
358 
359 	if (on)
360 		return rzg2l_csi2_dphy_enable(csi2);
361 
362 	return rzg2l_csi2_dphy_disable(csi2);
363 }
364 
365 static void rzg2l_csi2_mipi_link_enable(struct rzg2l_csi2 *csi2)
366 {
367 	unsigned long vclk_rate = csi2->vclk_rate / HZ_PER_MHZ;
368 	u32 frrskw, frrclk, frrskw_coeff, frrclk_coeff;
369 
370 	/* Select data lanes */
371 	rzg2l_csi2_write(csi2, CSI2nMCT0, CSI2nMCT0_VDLN(csi2->lanes));
372 
373 	frrskw_coeff = 3 * vclk_rate * 8;
374 	frrclk_coeff = frrskw_coeff / 2;
375 	frrskw = DIV_ROUND_UP(frrskw_coeff, csi2->hsfreq);
376 	frrclk = DIV_ROUND_UP(frrclk_coeff, csi2->hsfreq);
377 	rzg2l_csi2_write(csi2, CSI2nMCT2, CSI2nMCT2_FRRSKW(frrskw) |
378 			 CSI2nMCT2_FRRCLK(frrclk));
379 
380 	/*
381 	 * Select data type.
382 	 * FS, FE, LS, LE, Generic Short Packet Codes 1 to 8,
383 	 * Generic Long Packet Data Types 1 to 4 YUV422 8-bit,
384 	 * RGB565, RGB888, RAW8 to RAW20, User-defined 8-bit
385 	 * data types 1 to 8
386 	 */
387 	rzg2l_csi2_write(csi2, CSI2nDTEL, 0xf778ff0f);
388 	rzg2l_csi2_write(csi2, CSI2nDTEH, 0x00ffff1f);
389 
390 	/* Enable LINK reception */
391 	rzg2l_csi2_write(csi2, CSI2nMCT3, CSI2nMCT3_RXEN);
392 }
393 
394 static void rzg2l_csi2_mipi_link_disable(struct rzg2l_csi2 *csi2)
395 {
396 	unsigned int timeout = VSRSTS_RETRIES;
397 
398 	/* Stop LINK reception */
399 	rzg2l_csi2_clr(csi2, CSI2nMCT3, CSI2nMCT3_RXEN);
400 
401 	/* Request a software reset of the LINK Video Pixel Interface */
402 	rzg2l_csi2_write(csi2, CSI2nRTCT, CSI2nRTCT_VSRST);
403 
404 	/* Make sure CSI2nRTST.VSRSTS bit is cleared */
405 	while (timeout--) {
406 		if (!(rzg2l_csi2_read(csi2, CSI2nRTST) & CSI2nRTST_VSRSTS))
407 			break;
408 		usleep_range(100, 200);
409 	};
410 
411 	if (!timeout)
412 		dev_err(csi2->dev, "Clearing CSI2nRTST.VSRSTS timed out\n");
413 }
414 
415 static int rzg2l_csi2_mipi_link_setting(struct v4l2_subdev *sd, bool on)
416 {
417 	struct rzg2l_csi2 *csi2 = sd_to_csi2(sd);
418 
419 	if (on)
420 		rzg2l_csi2_mipi_link_enable(csi2);
421 	else
422 		rzg2l_csi2_mipi_link_disable(csi2);
423 
424 	return 0;
425 }
426 
427 static int rzg2l_csi2_s_stream(struct v4l2_subdev *sd, int enable)
428 {
429 	struct rzg2l_csi2 *csi2 = sd_to_csi2(sd);
430 	int s_stream_ret = 0;
431 	int ret;
432 
433 	if (enable) {
434 		int ret;
435 
436 		ret = pm_runtime_resume_and_get(csi2->dev);
437 		if (ret)
438 			return ret;
439 
440 		ret = rzg2l_csi2_mipi_link_setting(sd, 1);
441 		if (ret)
442 			goto err_pm_put;
443 
444 		ret = reset_control_deassert(csi2->cmn_rstb);
445 		if (ret)
446 			goto err_mipi_link_disable;
447 	}
448 
449 	ret = v4l2_subdev_call(csi2->remote_source, video, s_stream, enable);
450 	if (ret)
451 		s_stream_ret = ret;
452 
453 	if (enable && ret)
454 		goto err_assert_rstb;
455 
456 	if (!enable) {
457 		ret = rzg2l_csi2_dphy_setting(sd, 0);
458 		if (ret && !s_stream_ret)
459 			s_stream_ret = ret;
460 		ret = rzg2l_csi2_mipi_link_setting(sd, 0);
461 		if (ret && !s_stream_ret)
462 			s_stream_ret = ret;
463 
464 		pm_runtime_put_sync(csi2->dev);
465 	}
466 
467 	return s_stream_ret;
468 
469 err_assert_rstb:
470 	reset_control_assert(csi2->cmn_rstb);
471 err_mipi_link_disable:
472 	rzg2l_csi2_mipi_link_setting(sd, 0);
473 err_pm_put:
474 	pm_runtime_put_sync(csi2->dev);
475 	return ret;
476 }
477 
478 static int rzg2l_csi2_pre_streamon(struct v4l2_subdev *sd, u32 flags)
479 {
480 	return rzg2l_csi2_dphy_setting(sd, 1);
481 }
482 
483 static int rzg2l_csi2_post_streamoff(struct v4l2_subdev *sd)
484 {
485 	struct rzg2l_csi2 *csi2 = sd_to_csi2(sd);
486 
487 	/*
488 	 * In ideal case D-PHY will be disabled in s_stream(0) callback
489 	 * as mentioned in the HW manual. The below will only happen when
490 	 * pre_streamon succeeds and further down the line s_stream(1)
491 	 * fails so we need to undo things in post_streamoff.
492 	 */
493 	if (csi2->dphy_enabled)
494 		return rzg2l_csi2_dphy_setting(sd, 0);
495 
496 	return 0;
497 }
498 
499 static int rzg2l_csi2_set_format(struct v4l2_subdev *sd,
500 				 struct v4l2_subdev_state *state,
501 				 struct v4l2_subdev_format *fmt)
502 {
503 	struct v4l2_mbus_framefmt *src_format;
504 	struct v4l2_mbus_framefmt *sink_format;
505 
506 	src_format = v4l2_subdev_get_pad_format(sd, state, RZG2L_CSI2_SOURCE);
507 	if (fmt->pad == RZG2L_CSI2_SOURCE) {
508 		fmt->format = *src_format;
509 		return 0;
510 	}
511 
512 	sink_format = v4l2_subdev_get_pad_format(sd, state, RZG2L_CSI2_SINK);
513 
514 	if (!rzg2l_csi2_code_to_fmt(fmt->format.code))
515 		sink_format->code = rzg2l_csi2_formats[0].code;
516 	else
517 		sink_format->code = fmt->format.code;
518 
519 	sink_format->field = V4L2_FIELD_NONE;
520 	sink_format->colorspace = fmt->format.colorspace;
521 	sink_format->xfer_func = fmt->format.xfer_func;
522 	sink_format->ycbcr_enc = fmt->format.ycbcr_enc;
523 	sink_format->quantization = fmt->format.quantization;
524 	sink_format->width = clamp_t(u32, fmt->format.width,
525 				     RZG2L_CSI2_MIN_WIDTH, RZG2L_CSI2_MAX_WIDTH);
526 	sink_format->height = clamp_t(u32, fmt->format.height,
527 				      RZG2L_CSI2_MIN_HEIGHT, RZG2L_CSI2_MAX_HEIGHT);
528 	fmt->format = *sink_format;
529 
530 	/* propagate format to source pad */
531 	*src_format = *sink_format;
532 
533 	return 0;
534 }
535 
536 static int rzg2l_csi2_init_config(struct v4l2_subdev *sd,
537 				  struct v4l2_subdev_state *sd_state)
538 {
539 	struct v4l2_subdev_format fmt = { .pad = RZG2L_CSI2_SINK, };
540 
541 	fmt.format.width = RZG2L_CSI2_DEFAULT_WIDTH;
542 	fmt.format.height = RZG2L_CSI2_DEFAULT_HEIGHT;
543 	fmt.format.field = V4L2_FIELD_NONE;
544 	fmt.format.code = RZG2L_CSI2_DEFAULT_FMT;
545 	fmt.format.colorspace = V4L2_COLORSPACE_SRGB;
546 	fmt.format.ycbcr_enc = V4L2_YCBCR_ENC_DEFAULT;
547 	fmt.format.quantization = V4L2_QUANTIZATION_DEFAULT;
548 	fmt.format.xfer_func = V4L2_XFER_FUNC_DEFAULT;
549 
550 	return rzg2l_csi2_set_format(sd, sd_state, &fmt);
551 }
552 
553 static int rzg2l_csi2_enum_mbus_code(struct v4l2_subdev *sd,
554 				     struct v4l2_subdev_state *sd_state,
555 				     struct v4l2_subdev_mbus_code_enum *code)
556 {
557 	if (code->index >= ARRAY_SIZE(rzg2l_csi2_formats))
558 		return -EINVAL;
559 
560 	code->code = rzg2l_csi2_formats[code->index].code;
561 
562 	return 0;
563 }
564 
565 static int rzg2l_csi2_enum_frame_size(struct v4l2_subdev *sd,
566 				      struct v4l2_subdev_state *sd_state,
567 				      struct v4l2_subdev_frame_size_enum *fse)
568 {
569 	if (fse->index != 0)
570 		return -EINVAL;
571 
572 	fse->min_width = RZG2L_CSI2_MIN_WIDTH;
573 	fse->min_height = RZG2L_CSI2_MIN_HEIGHT;
574 	fse->max_width = RZG2L_CSI2_MAX_WIDTH;
575 	fse->max_height = RZG2L_CSI2_MAX_HEIGHT;
576 
577 	return 0;
578 }
579 
580 static const struct v4l2_subdev_video_ops rzg2l_csi2_video_ops = {
581 	.s_stream = rzg2l_csi2_s_stream,
582 	.pre_streamon = rzg2l_csi2_pre_streamon,
583 	.post_streamoff = rzg2l_csi2_post_streamoff,
584 };
585 
586 static const struct v4l2_subdev_pad_ops rzg2l_csi2_pad_ops = {
587 	.enum_mbus_code = rzg2l_csi2_enum_mbus_code,
588 	.init_cfg = rzg2l_csi2_init_config,
589 	.enum_frame_size = rzg2l_csi2_enum_frame_size,
590 	.set_fmt = rzg2l_csi2_set_format,
591 	.get_fmt = v4l2_subdev_get_fmt,
592 };
593 
594 static const struct v4l2_subdev_ops rzg2l_csi2_subdev_ops = {
595 	.video	= &rzg2l_csi2_video_ops,
596 	.pad	= &rzg2l_csi2_pad_ops,
597 };
598 
599 /* -----------------------------------------------------------------------------
600  * Async handling and registration of subdevices and links.
601  */
602 
603 static int rzg2l_csi2_notify_bound(struct v4l2_async_notifier *notifier,
604 				   struct v4l2_subdev *subdev,
605 				   struct v4l2_async_subdev *asd)
606 {
607 	struct rzg2l_csi2 *csi2 = notifier_to_csi2(notifier);
608 
609 	csi2->remote_source = subdev;
610 
611 	dev_dbg(csi2->dev, "Bound subdev: %s pad\n", subdev->name);
612 
613 	return media_create_pad_link(&subdev->entity, RZG2L_CSI2_SINK,
614 				     &csi2->subdev.entity, 0,
615 				     MEDIA_LNK_FL_ENABLED |
616 				     MEDIA_LNK_FL_IMMUTABLE);
617 }
618 
619 static void rzg2l_csi2_notify_unbind(struct v4l2_async_notifier *notifier,
620 				     struct v4l2_subdev *subdev,
621 				     struct v4l2_async_subdev *asd)
622 {
623 	struct rzg2l_csi2 *csi2 = notifier_to_csi2(notifier);
624 
625 	csi2->remote_source = NULL;
626 
627 	dev_dbg(csi2->dev, "Unbind subdev %s\n", subdev->name);
628 }
629 
630 static const struct v4l2_async_notifier_operations rzg2l_csi2_notify_ops = {
631 	.bound = rzg2l_csi2_notify_bound,
632 	.unbind = rzg2l_csi2_notify_unbind,
633 };
634 
635 static int rzg2l_csi2_parse_v4l2(struct rzg2l_csi2 *csi2,
636 				 struct v4l2_fwnode_endpoint *vep)
637 {
638 	/* Only port 0 endpoint 0 is valid. */
639 	if (vep->base.port || vep->base.id)
640 		return -ENOTCONN;
641 
642 	csi2->lanes = vep->bus.mipi_csi2.num_data_lanes;
643 
644 	return 0;
645 }
646 
647 static int rzg2l_csi2_parse_dt(struct rzg2l_csi2 *csi2)
648 {
649 	struct v4l2_fwnode_endpoint v4l2_ep = {
650 		.bus_type = V4L2_MBUS_CSI2_DPHY
651 	};
652 	struct v4l2_async_subdev *asd;
653 	struct fwnode_handle *fwnode;
654 	struct fwnode_handle *ep;
655 	int ret;
656 
657 	ep = fwnode_graph_get_endpoint_by_id(dev_fwnode(csi2->dev), 0, 0, 0);
658 	if (!ep) {
659 		dev_err(csi2->dev, "Not connected to subdevice\n");
660 		return -EINVAL;
661 	}
662 
663 	ret = v4l2_fwnode_endpoint_parse(ep, &v4l2_ep);
664 	if (ret) {
665 		dev_err(csi2->dev, "Could not parse v4l2 endpoint\n");
666 		fwnode_handle_put(ep);
667 		return -EINVAL;
668 	}
669 
670 	ret = rzg2l_csi2_parse_v4l2(csi2, &v4l2_ep);
671 	if (ret) {
672 		fwnode_handle_put(ep);
673 		return ret;
674 	}
675 
676 	fwnode = fwnode_graph_get_remote_endpoint(ep);
677 	fwnode_handle_put(ep);
678 
679 	v4l2_async_nf_init(&csi2->notifier);
680 	csi2->notifier.ops = &rzg2l_csi2_notify_ops;
681 
682 	asd = v4l2_async_nf_add_fwnode(&csi2->notifier, fwnode,
683 				       struct v4l2_async_subdev);
684 	fwnode_handle_put(fwnode);
685 	if (IS_ERR(asd))
686 		return PTR_ERR(asd);
687 
688 	ret = v4l2_async_subdev_nf_register(&csi2->subdev, &csi2->notifier);
689 	if (ret)
690 		v4l2_async_nf_cleanup(&csi2->notifier);
691 
692 	return ret;
693 }
694 
695 static int rzg2l_validate_csi2_lanes(struct rzg2l_csi2 *csi2)
696 {
697 	int lanes;
698 	int ret;
699 
700 	if (csi2->lanes != 1 && csi2->lanes != 2 && csi2->lanes != 4) {
701 		dev_err(csi2->dev, "Unsupported number of data-lanes: %u\n",
702 			csi2->lanes);
703 		return -EINVAL;
704 	}
705 
706 	ret = pm_runtime_resume_and_get(csi2->dev);
707 	if (ret)
708 		return ret;
709 
710 	/* Checking the maximum lanes support for CSI-2 module */
711 	lanes = (rzg2l_csi2_read(csi2, CSI2nMCG) & CSI2nMCG_SDLN) >> 8;
712 	if (lanes < csi2->lanes) {
713 		dev_err(csi2->dev,
714 			"Failed to support %d data lanes\n", csi2->lanes);
715 		ret = -EINVAL;
716 	}
717 
718 	pm_runtime_put_sync(csi2->dev);
719 
720 	return ret;
721 }
722 
723 /* -----------------------------------------------------------------------------
724  * Platform Device Driver.
725  */
726 
727 static const struct media_entity_operations rzg2l_csi2_entity_ops = {
728 	.link_validate = v4l2_subdev_link_validate,
729 };
730 
731 static int rzg2l_csi2_probe(struct platform_device *pdev)
732 {
733 	struct rzg2l_csi2 *csi2;
734 	struct clk *vclk;
735 	int ret;
736 
737 	csi2 = devm_kzalloc(&pdev->dev, sizeof(*csi2), GFP_KERNEL);
738 	if (!csi2)
739 		return -ENOMEM;
740 
741 	csi2->base = devm_platform_ioremap_resource(pdev, 0);
742 	if (IS_ERR(csi2->base))
743 		return PTR_ERR(csi2->base);
744 
745 	csi2->cmn_rstb = devm_reset_control_get_exclusive(&pdev->dev, "cmn-rstb");
746 	if (IS_ERR(csi2->cmn_rstb))
747 		return dev_err_probe(&pdev->dev, PTR_ERR(csi2->cmn_rstb),
748 				     "Failed to get cpg cmn-rstb\n");
749 
750 	csi2->presetn = devm_reset_control_get_shared(&pdev->dev, "presetn");
751 	if (IS_ERR(csi2->presetn))
752 		return dev_err_probe(&pdev->dev, PTR_ERR(csi2->presetn),
753 				     "Failed to get cpg presetn\n");
754 
755 	csi2->sysclk = devm_clk_get(&pdev->dev, "system");
756 	if (IS_ERR(csi2->sysclk))
757 		return dev_err_probe(&pdev->dev, PTR_ERR(csi2->sysclk),
758 				     "Failed to get system clk\n");
759 
760 	vclk = clk_get(&pdev->dev, "video");
761 	if (IS_ERR(vclk))
762 		return dev_err_probe(&pdev->dev, PTR_ERR(vclk),
763 				     "Failed to get video clock\n");
764 	csi2->vclk_rate = clk_get_rate(vclk);
765 	clk_put(vclk);
766 
767 	csi2->dev = &pdev->dev;
768 
769 	platform_set_drvdata(pdev, csi2);
770 
771 	ret = rzg2l_csi2_parse_dt(csi2);
772 	if (ret)
773 		return ret;
774 
775 	pm_runtime_enable(&pdev->dev);
776 
777 	ret = rzg2l_validate_csi2_lanes(csi2);
778 	if (ret)
779 		goto error_pm;
780 
781 	csi2->subdev.dev = &pdev->dev;
782 	v4l2_subdev_init(&csi2->subdev, &rzg2l_csi2_subdev_ops);
783 	v4l2_set_subdevdata(&csi2->subdev, &pdev->dev);
784 	snprintf(csi2->subdev.name, sizeof(csi2->subdev.name),
785 		 "csi-%s", dev_name(&pdev->dev));
786 	csi2->subdev.flags = V4L2_SUBDEV_FL_HAS_DEVNODE;
787 
788 	csi2->subdev.entity.function = MEDIA_ENT_F_VID_IF_BRIDGE;
789 	csi2->subdev.entity.ops = &rzg2l_csi2_entity_ops;
790 
791 	csi2->pads[RZG2L_CSI2_SINK].flags = MEDIA_PAD_FL_SINK;
792 	/*
793 	 * TODO: RZ/G2L CSI2 supports 4 virtual channels, as virtual
794 	 * channels should be implemented by streams API which is under
795 	 * development lets hardcode to VC0 for now.
796 	 */
797 	csi2->pads[RZG2L_CSI2_SOURCE].flags = MEDIA_PAD_FL_SOURCE;
798 	ret = media_entity_pads_init(&csi2->subdev.entity, 2, csi2->pads);
799 	if (ret)
800 		goto error_pm;
801 
802 	ret = v4l2_subdev_init_finalize(&csi2->subdev);
803 	if (ret < 0)
804 		goto error_async;
805 
806 	ret = v4l2_async_register_subdev(&csi2->subdev);
807 	if (ret < 0)
808 		goto error_subdev;
809 
810 	return 0;
811 
812 error_subdev:
813 	v4l2_subdev_cleanup(&csi2->subdev);
814 error_async:
815 	v4l2_async_nf_unregister(&csi2->notifier);
816 	v4l2_async_nf_cleanup(&csi2->notifier);
817 	media_entity_cleanup(&csi2->subdev.entity);
818 error_pm:
819 	pm_runtime_disable(&pdev->dev);
820 
821 	return ret;
822 }
823 
824 static int rzg2l_csi2_remove(struct platform_device *pdev)
825 {
826 	struct rzg2l_csi2 *csi2 = platform_get_drvdata(pdev);
827 
828 	v4l2_async_nf_unregister(&csi2->notifier);
829 	v4l2_async_nf_cleanup(&csi2->notifier);
830 	v4l2_async_unregister_subdev(&csi2->subdev);
831 	v4l2_subdev_cleanup(&csi2->subdev);
832 	media_entity_cleanup(&csi2->subdev.entity);
833 	pm_runtime_disable(&pdev->dev);
834 
835 	return 0;
836 }
837 
838 static int __maybe_unused rzg2l_csi2_pm_runtime_suspend(struct device *dev)
839 {
840 	struct rzg2l_csi2 *csi2 = dev_get_drvdata(dev);
841 
842 	reset_control_assert(csi2->presetn);
843 
844 	return 0;
845 }
846 
847 static int __maybe_unused rzg2l_csi2_pm_runtime_resume(struct device *dev)
848 {
849 	struct rzg2l_csi2 *csi2 = dev_get_drvdata(dev);
850 
851 	return reset_control_deassert(csi2->presetn);
852 }
853 
854 static const struct dev_pm_ops rzg2l_csi2_pm_ops = {
855 	SET_RUNTIME_PM_OPS(rzg2l_csi2_pm_runtime_suspend, rzg2l_csi2_pm_runtime_resume, NULL)
856 };
857 
858 static const struct of_device_id rzg2l_csi2_of_table[] = {
859 	{ .compatible = "renesas,rzg2l-csi2", },
860 	{ /* sentinel */ }
861 };
862 
863 static struct platform_driver rzg2l_csi2_pdrv = {
864 	.remove	= rzg2l_csi2_remove,
865 	.probe	= rzg2l_csi2_probe,
866 	.driver	= {
867 		.name = "rzg2l-csi2",
868 		.of_match_table = rzg2l_csi2_of_table,
869 		.pm = &rzg2l_csi2_pm_ops,
870 	},
871 };
872 
873 module_platform_driver(rzg2l_csi2_pdrv);
874 
875 MODULE_AUTHOR("Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>");
876 MODULE_DESCRIPTION("Renesas RZ/G2L MIPI CSI2 receiver driver");
877 MODULE_LICENSE("GPL");
878