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_graph.h>
15 #include <linux/platform_device.h>
16 #include <linux/pm_runtime.h>
17 #include <linux/reset.h>
18 #include <linux/sys_soc.h>
19 #include <linux/units.h>
20 
21 #include <media/v4l2-ctrls.h>
22 #include <media/v4l2-device.h>
23 #include <media/v4l2-fwnode.h>
24 #include <media/v4l2-mc.h>
25 #include <media/v4l2-subdev.h>
26 
27 /* LINK registers */
28 /* Module Configuration Register */
29 #define CSI2nMCG			0x0
30 #define CSI2nMCG_SDLN			GENMASK(11, 8)
31 
32 /* Module Control Register 0 */
33 #define CSI2nMCT0			0x10
34 #define CSI2nMCT0_VDLN(x)		((x) << 0)
35 
36 /* Module Control Register 2 */
37 #define CSI2nMCT2			0x18
38 #define CSI2nMCT2_FRRSKW(x)		((x) << 16)
39 #define CSI2nMCT2_FRRCLK(x)		((x) << 0)
40 
41 /* Module Control Register 3 */
42 #define CSI2nMCT3			0x1c
43 #define CSI2nMCT3_RXEN			BIT(0)
44 
45 /* Reset Control Register */
46 #define CSI2nRTCT			0x28
47 #define CSI2nRTCT_VSRST			BIT(0)
48 
49 /* Reset Status Register */
50 #define CSI2nRTST			0x2c
51 #define CSI2nRTST_VSRSTS		BIT(0)
52 
53 /* Receive Data Type Enable Low Register */
54 #define CSI2nDTEL			0x60
55 
56 /* Receive Data Type Enable High Register */
57 #define CSI2nDTEH			0x64
58 
59 /* DPHY registers */
60 /* D-PHY Control Register 0 */
61 #define CSIDPHYCTRL0			0x400
62 #define CSIDPHYCTRL0_EN_LDO1200		BIT(1)
63 #define CSIDPHYCTRL0_EN_BGR		BIT(0)
64 
65 /* D-PHY Timing Register 0 */
66 #define CSIDPHYTIM0			0x404
67 #define CSIDPHYTIM0_TCLK_MISS(x)	((x) << 24)
68 #define CSIDPHYTIM0_T_INIT(x)		((x) << 0)
69 
70 /* D-PHY Timing Register 1 */
71 #define CSIDPHYTIM1			0x408
72 #define CSIDPHYTIM1_THS_PREPARE(x)	((x) << 24)
73 #define CSIDPHYTIM1_TCLK_PREPARE(x)	((x) << 16)
74 #define CSIDPHYTIM1_THS_SETTLE(x)	((x) << 8)
75 #define CSIDPHYTIM1_TCLK_SETTLE(x)	((x) << 0)
76 
77 /* D-PHY Skew Adjustment Function */
78 #define CSIDPHYSKW0			0x460
79 #define CSIDPHYSKW0_UTIL_DL0_SKW_ADJ(x)	((x) & 0x3)
80 #define CSIDPHYSKW0_UTIL_DL1_SKW_ADJ(x)	(((x) & 0x3) << 4)
81 #define CSIDPHYSKW0_UTIL_DL2_SKW_ADJ(x)	(((x) & 0x3) << 8)
82 #define CSIDPHYSKW0_UTIL_DL3_SKW_ADJ(x)	(((x) & 0x3) << 12)
83 #define CSIDPHYSKW0_DEFAULT_SKW		(CSIDPHYSKW0_UTIL_DL0_SKW_ADJ(1) | \
84 					 CSIDPHYSKW0_UTIL_DL1_SKW_ADJ(1) | \
85 					 CSIDPHYSKW0_UTIL_DL2_SKW_ADJ(1) | \
86 					 CSIDPHYSKW0_UTIL_DL3_SKW_ADJ(1))
87 
88 #define VSRSTS_RETRIES			20
89 
90 #define RZG2L_CSI2_MIN_WIDTH		320
91 #define RZG2L_CSI2_MIN_HEIGHT		240
92 #define RZG2L_CSI2_MAX_WIDTH		2800
93 #define RZG2L_CSI2_MAX_HEIGHT		4095
94 
95 #define RZG2L_CSI2_DEFAULT_WIDTH	RZG2L_CSI2_MIN_WIDTH
96 #define RZG2L_CSI2_DEFAULT_HEIGHT	RZG2L_CSI2_MIN_HEIGHT
97 #define RZG2L_CSI2_DEFAULT_FMT		MEDIA_BUS_FMT_UYVY8_1X16
98 
99 enum rzg2l_csi2_pads {
100 	RZG2L_CSI2_SINK = 0,
101 	RZG2L_CSI2_SOURCE,
102 	NR_OF_RZG2L_CSI2_PAD,
103 };
104 
105 struct rzg2l_csi2 {
106 	struct device *dev;
107 	void __iomem *base;
108 	struct reset_control *presetn;
109 	struct reset_control *cmn_rstb;
110 	struct clk *sysclk;
111 	unsigned long vclk_rate;
112 
113 	struct v4l2_subdev subdev;
114 	struct media_pad pads[NR_OF_RZG2L_CSI2_PAD];
115 
116 	struct v4l2_async_notifier notifier;
117 	struct v4l2_subdev *remote_source;
118 
119 	unsigned short lanes;
120 	unsigned long hsfreq;
121 
122 	bool dphy_enabled;
123 };
124 
125 struct rzg2l_csi2_timings {
126 	u32 t_init;
127 	u32 tclk_miss;
128 	u32 tclk_settle;
129 	u32 ths_settle;
130 	u32 tclk_prepare;
131 	u32 ths_prepare;
132 	u32 max_hsfreq;
133 };
134 
135 static const struct rzg2l_csi2_timings rzg2l_csi2_global_timings[] = {
136 	{
137 		.max_hsfreq = 80,
138 		.t_init = 79801,
139 		.tclk_miss = 4,
140 		.tclk_settle = 23,
141 		.ths_settle = 31,
142 		.tclk_prepare = 10,
143 		.ths_prepare = 19,
144 	},
145 	{
146 		.max_hsfreq = 125,
147 		.t_init = 79801,
148 		.tclk_miss = 4,
149 		.tclk_settle = 23,
150 		.ths_settle = 28,
151 		.tclk_prepare = 10,
152 		.ths_prepare = 19,
153 	},
154 	{
155 		.max_hsfreq = 250,
156 		.t_init = 79801,
157 		.tclk_miss = 4,
158 		.tclk_settle = 23,
159 		.ths_settle = 22,
160 		.tclk_prepare = 10,
161 		.ths_prepare = 16,
162 	},
163 	{
164 		.max_hsfreq = 360,
165 		.t_init = 79801,
166 		.tclk_miss = 4,
167 		.tclk_settle = 18,
168 		.ths_settle = 19,
169 		.tclk_prepare = 10,
170 		.ths_prepare = 10,
171 	},
172 	{
173 		.max_hsfreq = 1500,
174 		.t_init = 79801,
175 		.tclk_miss = 4,
176 		.tclk_settle = 18,
177 		.ths_settle = 18,
178 		.tclk_prepare = 10,
179 		.ths_prepare = 10,
180 	},
181 };
182 
183 struct rzg2l_csi2_format {
184 	u32 code;
185 	unsigned int datatype;
186 	unsigned int bpp;
187 };
188 
189 static const struct rzg2l_csi2_format rzg2l_csi2_formats[] = {
190 	{ .code = MEDIA_BUS_FMT_UYVY8_1X16,	.datatype = 0x1e, .bpp = 16 },
191 };
192 
193 static inline struct rzg2l_csi2 *sd_to_csi2(struct v4l2_subdev *sd)
194 {
195 	return container_of(sd, struct rzg2l_csi2, subdev);
196 }
197 
198 static const struct rzg2l_csi2_format *rzg2l_csi2_code_to_fmt(unsigned int code)
199 {
200 	unsigned int i;
201 
202 	for (i = 0; i < ARRAY_SIZE(rzg2l_csi2_formats); i++)
203 		if (rzg2l_csi2_formats[i].code == code)
204 			return &rzg2l_csi2_formats[i];
205 
206 	return NULL;
207 }
208 
209 static inline struct rzg2l_csi2 *notifier_to_csi2(struct v4l2_async_notifier *n)
210 {
211 	return container_of(n, struct rzg2l_csi2, notifier);
212 }
213 
214 static u32 rzg2l_csi2_read(struct rzg2l_csi2 *csi2, unsigned int reg)
215 {
216 	return ioread32(csi2->base + reg);
217 }
218 
219 static void rzg2l_csi2_write(struct rzg2l_csi2 *csi2, unsigned int reg,
220 			     u32 data)
221 {
222 	iowrite32(data, csi2->base + reg);
223 }
224 
225 static void rzg2l_csi2_set(struct rzg2l_csi2 *csi2, unsigned int reg, u32 set)
226 {
227 	rzg2l_csi2_write(csi2, reg, rzg2l_csi2_read(csi2, reg) | set);
228 }
229 
230 static void rzg2l_csi2_clr(struct rzg2l_csi2 *csi2, unsigned int reg, u32 clr)
231 {
232 	rzg2l_csi2_write(csi2, reg, rzg2l_csi2_read(csi2, reg) & ~clr);
233 }
234 
235 static int rzg2l_csi2_calc_mbps(struct rzg2l_csi2 *csi2)
236 {
237 	struct v4l2_subdev *source = csi2->remote_source;
238 	const struct rzg2l_csi2_format *format;
239 	const struct v4l2_mbus_framefmt *fmt;
240 	struct v4l2_subdev_state *state;
241 	struct v4l2_ctrl *ctrl;
242 	u64 mbps;
243 
244 	/* Read the pixel rate control from remote. */
245 	ctrl = v4l2_ctrl_find(source->ctrl_handler, V4L2_CID_PIXEL_RATE);
246 	if (!ctrl) {
247 		dev_err(csi2->dev, "no pixel rate control in subdev %s\n",
248 			source->name);
249 		return -EINVAL;
250 	}
251 
252 	state = v4l2_subdev_lock_and_get_active_state(&csi2->subdev);
253 	fmt = v4l2_subdev_get_pad_format(&csi2->subdev, state, RZG2L_CSI2_SINK);
254 	format = rzg2l_csi2_code_to_fmt(fmt->code);
255 	v4l2_subdev_unlock_state(state);
256 
257 	/*
258 	 * Calculate hsfreq in Mbps
259 	 * hsfreq = (pixel_rate * bits_per_sample) / number_of_lanes
260 	 */
261 	mbps = v4l2_ctrl_g_ctrl_int64(ctrl) * format->bpp;
262 	do_div(mbps, csi2->lanes * 1000000);
263 
264 	return mbps;
265 }
266 
267 /* -----------------------------------------------------------------------------
268  * DPHY setting
269  */
270 
271 static int rzg2l_csi2_dphy_disable(struct rzg2l_csi2 *csi2)
272 {
273 	int ret;
274 
275 	/* Reset the CRU (D-PHY) */
276 	ret = reset_control_assert(csi2->cmn_rstb);
277 	if (ret)
278 		return ret;
279 
280 	/* Stop the D-PHY clock */
281 	clk_disable_unprepare(csi2->sysclk);
282 
283 	/* Cancel the EN_LDO1200 register setting */
284 	rzg2l_csi2_clr(csi2, CSIDPHYCTRL0, CSIDPHYCTRL0_EN_LDO1200);
285 
286 	/* Cancel the EN_BGR register setting */
287 	rzg2l_csi2_clr(csi2, CSIDPHYCTRL0, CSIDPHYCTRL0_EN_BGR);
288 
289 	csi2->dphy_enabled = false;
290 
291 	return 0;
292 }
293 
294 static int rzg2l_csi2_dphy_enable(struct rzg2l_csi2 *csi2)
295 {
296 	const struct rzg2l_csi2_timings *dphy_timing;
297 	u32 dphytim0, dphytim1;
298 	unsigned int i;
299 	int mbps;
300 	int ret;
301 
302 	mbps = rzg2l_csi2_calc_mbps(csi2);
303 	if (mbps < 0)
304 		return mbps;
305 
306 	csi2->hsfreq = mbps;
307 
308 	/* Set DPHY timing parameters */
309 	for (i = 0; i < ARRAY_SIZE(rzg2l_csi2_global_timings); ++i) {
310 		dphy_timing = &rzg2l_csi2_global_timings[i];
311 
312 		if (csi2->hsfreq <= dphy_timing->max_hsfreq)
313 			break;
314 	}
315 
316 	if (i >= ARRAY_SIZE(rzg2l_csi2_global_timings))
317 		return -EINVAL;
318 
319 	/* Set D-PHY timing parameters */
320 	dphytim0 = CSIDPHYTIM0_TCLK_MISS(dphy_timing->tclk_miss) |
321 			CSIDPHYTIM0_T_INIT(dphy_timing->t_init);
322 	dphytim1 = CSIDPHYTIM1_THS_PREPARE(dphy_timing->ths_prepare) |
323 			CSIDPHYTIM1_TCLK_PREPARE(dphy_timing->tclk_prepare) |
324 			CSIDPHYTIM1_THS_SETTLE(dphy_timing->ths_settle) |
325 			CSIDPHYTIM1_TCLK_SETTLE(dphy_timing->tclk_settle);
326 	rzg2l_csi2_write(csi2, CSIDPHYTIM0, dphytim0);
327 	rzg2l_csi2_write(csi2, CSIDPHYTIM1, dphytim1);
328 
329 	/* Enable D-PHY power control 0 */
330 	rzg2l_csi2_write(csi2, CSIDPHYSKW0, CSIDPHYSKW0_DEFAULT_SKW);
331 
332 	/* Set the EN_BGR bit */
333 	rzg2l_csi2_set(csi2, CSIDPHYCTRL0, CSIDPHYCTRL0_EN_BGR);
334 
335 	/* Delay 20us to be stable */
336 	usleep_range(20, 40);
337 
338 	/* Enable D-PHY power control 1 */
339 	rzg2l_csi2_set(csi2, CSIDPHYCTRL0, CSIDPHYCTRL0_EN_LDO1200);
340 
341 	/* Delay 10us to be stable */
342 	usleep_range(10, 20);
343 
344 	/* Start supplying the internal clock for the D-PHY block */
345 	ret = clk_prepare_enable(csi2->sysclk);
346 	if (ret)
347 		rzg2l_csi2_dphy_disable(csi2);
348 
349 	csi2->dphy_enabled = true;
350 
351 	return ret;
352 }
353 
354 static int rzg2l_csi2_dphy_setting(struct v4l2_subdev *sd, bool on)
355 {
356 	struct rzg2l_csi2 *csi2 = sd_to_csi2(sd);
357 
358 	if (on)
359 		return rzg2l_csi2_dphy_enable(csi2);
360 
361 	return rzg2l_csi2_dphy_disable(csi2);
362 }
363 
364 static void rzg2l_csi2_mipi_link_enable(struct rzg2l_csi2 *csi2)
365 {
366 	unsigned long vclk_rate = csi2->vclk_rate / HZ_PER_MHZ;
367 	u32 frrskw, frrclk, frrskw_coeff, frrclk_coeff;
368 
369 	/* Select data lanes */
370 	rzg2l_csi2_write(csi2, CSI2nMCT0, CSI2nMCT0_VDLN(csi2->lanes));
371 
372 	frrskw_coeff = 3 * vclk_rate * 8;
373 	frrclk_coeff = frrskw_coeff / 2;
374 	frrskw = DIV_ROUND_UP(frrskw_coeff, csi2->hsfreq);
375 	frrclk = DIV_ROUND_UP(frrclk_coeff, csi2->hsfreq);
376 	rzg2l_csi2_write(csi2, CSI2nMCT2, CSI2nMCT2_FRRSKW(frrskw) |
377 			 CSI2nMCT2_FRRCLK(frrclk));
378 
379 	/*
380 	 * Select data type.
381 	 * FS, FE, LS, LE, Generic Short Packet Codes 1 to 8,
382 	 * Generic Long Packet Data Types 1 to 4 YUV422 8-bit,
383 	 * RGB565, RGB888, RAW8 to RAW20, User-defined 8-bit
384 	 * data types 1 to 8
385 	 */
386 	rzg2l_csi2_write(csi2, CSI2nDTEL, 0xf778ff0f);
387 	rzg2l_csi2_write(csi2, CSI2nDTEH, 0x00ffff1f);
388 
389 	/* Enable LINK reception */
390 	rzg2l_csi2_write(csi2, CSI2nMCT3, CSI2nMCT3_RXEN);
391 }
392 
393 static void rzg2l_csi2_mipi_link_disable(struct rzg2l_csi2 *csi2)
394 {
395 	unsigned int timeout = VSRSTS_RETRIES;
396 
397 	/* Stop LINK reception */
398 	rzg2l_csi2_clr(csi2, CSI2nMCT3, CSI2nMCT3_RXEN);
399 
400 	/* Request a software reset of the LINK Video Pixel Interface */
401 	rzg2l_csi2_write(csi2, CSI2nRTCT, CSI2nRTCT_VSRST);
402 
403 	/* Make sure CSI2nRTST.VSRSTS bit is cleared */
404 	while (--timeout) {
405 		if (!(rzg2l_csi2_read(csi2, CSI2nRTST) & CSI2nRTST_VSRSTS))
406 			break;
407 		usleep_range(100, 200);
408 	}
409 
410 	if (!timeout)
411 		dev_err(csi2->dev, "Clearing CSI2nRTST.VSRSTS timed out\n");
412 }
413 
414 static int rzg2l_csi2_mipi_link_setting(struct v4l2_subdev *sd, bool on)
415 {
416 	struct rzg2l_csi2 *csi2 = sd_to_csi2(sd);
417 
418 	if (on)
419 		rzg2l_csi2_mipi_link_enable(csi2);
420 	else
421 		rzg2l_csi2_mipi_link_disable(csi2);
422 
423 	return 0;
424 }
425 
426 static int rzg2l_csi2_s_stream(struct v4l2_subdev *sd, int enable)
427 {
428 	struct rzg2l_csi2 *csi2 = sd_to_csi2(sd);
429 	int s_stream_ret = 0;
430 	int ret;
431 
432 	if (enable) {
433 		ret = pm_runtime_resume_and_get(csi2->dev);
434 		if (ret)
435 			return ret;
436 
437 		ret = rzg2l_csi2_mipi_link_setting(sd, 1);
438 		if (ret)
439 			goto err_pm_put;
440 
441 		ret = reset_control_deassert(csi2->cmn_rstb);
442 		if (ret)
443 			goto err_mipi_link_disable;
444 	}
445 
446 	ret = v4l2_subdev_call(csi2->remote_source, video, s_stream, enable);
447 	if (ret)
448 		s_stream_ret = ret;
449 
450 	if (enable && ret)
451 		goto err_assert_rstb;
452 
453 	if (!enable) {
454 		ret = rzg2l_csi2_dphy_setting(sd, 0);
455 		if (ret && !s_stream_ret)
456 			s_stream_ret = ret;
457 		ret = rzg2l_csi2_mipi_link_setting(sd, 0);
458 		if (ret && !s_stream_ret)
459 			s_stream_ret = ret;
460 
461 		pm_runtime_put_sync(csi2->dev);
462 	}
463 
464 	return s_stream_ret;
465 
466 err_assert_rstb:
467 	reset_control_assert(csi2->cmn_rstb);
468 err_mipi_link_disable:
469 	rzg2l_csi2_mipi_link_setting(sd, 0);
470 err_pm_put:
471 	pm_runtime_put_sync(csi2->dev);
472 	return ret;
473 }
474 
475 static int rzg2l_csi2_pre_streamon(struct v4l2_subdev *sd, u32 flags)
476 {
477 	return rzg2l_csi2_dphy_setting(sd, 1);
478 }
479 
480 static int rzg2l_csi2_post_streamoff(struct v4l2_subdev *sd)
481 {
482 	struct rzg2l_csi2 *csi2 = sd_to_csi2(sd);
483 
484 	/*
485 	 * In ideal case D-PHY will be disabled in s_stream(0) callback
486 	 * as mentioned in the HW manual. The below will only happen when
487 	 * pre_streamon succeeds and further down the line s_stream(1)
488 	 * fails so we need to undo things in post_streamoff.
489 	 */
490 	if (csi2->dphy_enabled)
491 		return rzg2l_csi2_dphy_setting(sd, 0);
492 
493 	return 0;
494 }
495 
496 static int rzg2l_csi2_set_format(struct v4l2_subdev *sd,
497 				 struct v4l2_subdev_state *state,
498 				 struct v4l2_subdev_format *fmt)
499 {
500 	struct v4l2_mbus_framefmt *src_format;
501 	struct v4l2_mbus_framefmt *sink_format;
502 
503 	src_format = v4l2_subdev_get_pad_format(sd, state, RZG2L_CSI2_SOURCE);
504 	if (fmt->pad == RZG2L_CSI2_SOURCE) {
505 		fmt->format = *src_format;
506 		return 0;
507 	}
508 
509 	sink_format = v4l2_subdev_get_pad_format(sd, state, RZG2L_CSI2_SINK);
510 
511 	if (!rzg2l_csi2_code_to_fmt(fmt->format.code))
512 		sink_format->code = rzg2l_csi2_formats[0].code;
513 	else
514 		sink_format->code = fmt->format.code;
515 
516 	sink_format->field = V4L2_FIELD_NONE;
517 	sink_format->colorspace = fmt->format.colorspace;
518 	sink_format->xfer_func = fmt->format.xfer_func;
519 	sink_format->ycbcr_enc = fmt->format.ycbcr_enc;
520 	sink_format->quantization = fmt->format.quantization;
521 	sink_format->width = clamp_t(u32, fmt->format.width,
522 				     RZG2L_CSI2_MIN_WIDTH, RZG2L_CSI2_MAX_WIDTH);
523 	sink_format->height = clamp_t(u32, fmt->format.height,
524 				      RZG2L_CSI2_MIN_HEIGHT, RZG2L_CSI2_MAX_HEIGHT);
525 	fmt->format = *sink_format;
526 
527 	/* propagate format to source pad */
528 	*src_format = *sink_format;
529 
530 	return 0;
531 }
532 
533 static int rzg2l_csi2_init_config(struct v4l2_subdev *sd,
534 				  struct v4l2_subdev_state *sd_state)
535 {
536 	struct v4l2_subdev_format fmt = { .pad = RZG2L_CSI2_SINK, };
537 
538 	fmt.format.width = RZG2L_CSI2_DEFAULT_WIDTH;
539 	fmt.format.height = RZG2L_CSI2_DEFAULT_HEIGHT;
540 	fmt.format.field = V4L2_FIELD_NONE;
541 	fmt.format.code = RZG2L_CSI2_DEFAULT_FMT;
542 	fmt.format.colorspace = V4L2_COLORSPACE_SRGB;
543 	fmt.format.ycbcr_enc = V4L2_YCBCR_ENC_DEFAULT;
544 	fmt.format.quantization = V4L2_QUANTIZATION_DEFAULT;
545 	fmt.format.xfer_func = V4L2_XFER_FUNC_DEFAULT;
546 
547 	return rzg2l_csi2_set_format(sd, sd_state, &fmt);
548 }
549 
550 static int rzg2l_csi2_enum_mbus_code(struct v4l2_subdev *sd,
551 				     struct v4l2_subdev_state *sd_state,
552 				     struct v4l2_subdev_mbus_code_enum *code)
553 {
554 	if (code->index >= ARRAY_SIZE(rzg2l_csi2_formats))
555 		return -EINVAL;
556 
557 	code->code = rzg2l_csi2_formats[code->index].code;
558 
559 	return 0;
560 }
561 
562 static int rzg2l_csi2_enum_frame_size(struct v4l2_subdev *sd,
563 				      struct v4l2_subdev_state *sd_state,
564 				      struct v4l2_subdev_frame_size_enum *fse)
565 {
566 	if (fse->index != 0)
567 		return -EINVAL;
568 
569 	fse->min_width = RZG2L_CSI2_MIN_WIDTH;
570 	fse->min_height = RZG2L_CSI2_MIN_HEIGHT;
571 	fse->max_width = RZG2L_CSI2_MAX_WIDTH;
572 	fse->max_height = RZG2L_CSI2_MAX_HEIGHT;
573 
574 	return 0;
575 }
576 
577 static const struct v4l2_subdev_video_ops rzg2l_csi2_video_ops = {
578 	.s_stream = rzg2l_csi2_s_stream,
579 	.pre_streamon = rzg2l_csi2_pre_streamon,
580 	.post_streamoff = rzg2l_csi2_post_streamoff,
581 };
582 
583 static const struct v4l2_subdev_pad_ops rzg2l_csi2_pad_ops = {
584 	.enum_mbus_code = rzg2l_csi2_enum_mbus_code,
585 	.init_cfg = rzg2l_csi2_init_config,
586 	.enum_frame_size = rzg2l_csi2_enum_frame_size,
587 	.set_fmt = rzg2l_csi2_set_format,
588 	.get_fmt = v4l2_subdev_get_fmt,
589 };
590 
591 static const struct v4l2_subdev_ops rzg2l_csi2_subdev_ops = {
592 	.video	= &rzg2l_csi2_video_ops,
593 	.pad	= &rzg2l_csi2_pad_ops,
594 };
595 
596 /* -----------------------------------------------------------------------------
597  * Async handling and registration of subdevices and links.
598  */
599 
600 static int rzg2l_csi2_notify_bound(struct v4l2_async_notifier *notifier,
601 				   struct v4l2_subdev *subdev,
602 				   struct v4l2_async_connection *asd)
603 {
604 	struct rzg2l_csi2 *csi2 = notifier_to_csi2(notifier);
605 
606 	csi2->remote_source = subdev;
607 
608 	dev_dbg(csi2->dev, "Bound subdev: %s pad\n", subdev->name);
609 
610 	return media_create_pad_link(&subdev->entity, RZG2L_CSI2_SINK,
611 				     &csi2->subdev.entity, 0,
612 				     MEDIA_LNK_FL_ENABLED |
613 				     MEDIA_LNK_FL_IMMUTABLE);
614 }
615 
616 static void rzg2l_csi2_notify_unbind(struct v4l2_async_notifier *notifier,
617 				     struct v4l2_subdev *subdev,
618 				     struct v4l2_async_connection *asd)
619 {
620 	struct rzg2l_csi2 *csi2 = notifier_to_csi2(notifier);
621 
622 	csi2->remote_source = NULL;
623 
624 	dev_dbg(csi2->dev, "Unbind subdev %s\n", subdev->name);
625 }
626 
627 static const struct v4l2_async_notifier_operations rzg2l_csi2_notify_ops = {
628 	.bound = rzg2l_csi2_notify_bound,
629 	.unbind = rzg2l_csi2_notify_unbind,
630 };
631 
632 static int rzg2l_csi2_parse_v4l2(struct rzg2l_csi2 *csi2,
633 				 struct v4l2_fwnode_endpoint *vep)
634 {
635 	/* Only port 0 endpoint 0 is valid. */
636 	if (vep->base.port || vep->base.id)
637 		return -ENOTCONN;
638 
639 	csi2->lanes = vep->bus.mipi_csi2.num_data_lanes;
640 
641 	return 0;
642 }
643 
644 static int rzg2l_csi2_parse_dt(struct rzg2l_csi2 *csi2)
645 {
646 	struct v4l2_fwnode_endpoint v4l2_ep = {
647 		.bus_type = V4L2_MBUS_CSI2_DPHY
648 	};
649 	struct v4l2_async_connection *asd;
650 	struct fwnode_handle *fwnode;
651 	struct fwnode_handle *ep;
652 	int ret;
653 
654 	ep = fwnode_graph_get_endpoint_by_id(dev_fwnode(csi2->dev), 0, 0, 0);
655 	if (!ep) {
656 		dev_err(csi2->dev, "Not connected to subdevice\n");
657 		return -EINVAL;
658 	}
659 
660 	ret = v4l2_fwnode_endpoint_parse(ep, &v4l2_ep);
661 	if (ret) {
662 		dev_err(csi2->dev, "Could not parse v4l2 endpoint\n");
663 		fwnode_handle_put(ep);
664 		return -EINVAL;
665 	}
666 
667 	ret = rzg2l_csi2_parse_v4l2(csi2, &v4l2_ep);
668 	if (ret) {
669 		fwnode_handle_put(ep);
670 		return ret;
671 	}
672 
673 	fwnode = fwnode_graph_get_remote_endpoint(ep);
674 	fwnode_handle_put(ep);
675 
676 	v4l2_async_subdev_nf_init(&csi2->notifier, &csi2->subdev);
677 	csi2->notifier.ops = &rzg2l_csi2_notify_ops;
678 
679 	asd = v4l2_async_nf_add_fwnode(&csi2->notifier, fwnode,
680 				       struct v4l2_async_connection);
681 	fwnode_handle_put(fwnode);
682 	if (IS_ERR(asd))
683 		return PTR_ERR(asd);
684 
685 	ret = v4l2_async_nf_register(&csi2->notifier);
686 	if (ret)
687 		v4l2_async_nf_cleanup(&csi2->notifier);
688 
689 	return ret;
690 }
691 
692 static int rzg2l_validate_csi2_lanes(struct rzg2l_csi2 *csi2)
693 {
694 	int lanes;
695 	int ret;
696 
697 	if (csi2->lanes != 1 && csi2->lanes != 2 && csi2->lanes != 4) {
698 		dev_err(csi2->dev, "Unsupported number of data-lanes: %u\n",
699 			csi2->lanes);
700 		return -EINVAL;
701 	}
702 
703 	ret = pm_runtime_resume_and_get(csi2->dev);
704 	if (ret)
705 		return ret;
706 
707 	/* Checking the maximum lanes support for CSI-2 module */
708 	lanes = (rzg2l_csi2_read(csi2, CSI2nMCG) & CSI2nMCG_SDLN) >> 8;
709 	if (lanes < csi2->lanes) {
710 		dev_err(csi2->dev,
711 			"Failed to support %d data lanes\n", csi2->lanes);
712 		ret = -EINVAL;
713 	}
714 
715 	pm_runtime_put_sync(csi2->dev);
716 
717 	return ret;
718 }
719 
720 /* -----------------------------------------------------------------------------
721  * Platform Device Driver.
722  */
723 
724 static const struct media_entity_operations rzg2l_csi2_entity_ops = {
725 	.link_validate = v4l2_subdev_link_validate,
726 };
727 
728 static int rzg2l_csi2_probe(struct platform_device *pdev)
729 {
730 	struct rzg2l_csi2 *csi2;
731 	struct clk *vclk;
732 	int ret;
733 
734 	csi2 = devm_kzalloc(&pdev->dev, sizeof(*csi2), GFP_KERNEL);
735 	if (!csi2)
736 		return -ENOMEM;
737 
738 	csi2->base = devm_platform_ioremap_resource(pdev, 0);
739 	if (IS_ERR(csi2->base))
740 		return PTR_ERR(csi2->base);
741 
742 	csi2->cmn_rstb = devm_reset_control_get_exclusive(&pdev->dev, "cmn-rstb");
743 	if (IS_ERR(csi2->cmn_rstb))
744 		return dev_err_probe(&pdev->dev, PTR_ERR(csi2->cmn_rstb),
745 				     "Failed to get cpg cmn-rstb\n");
746 
747 	csi2->presetn = devm_reset_control_get_shared(&pdev->dev, "presetn");
748 	if (IS_ERR(csi2->presetn))
749 		return dev_err_probe(&pdev->dev, PTR_ERR(csi2->presetn),
750 				     "Failed to get cpg presetn\n");
751 
752 	csi2->sysclk = devm_clk_get(&pdev->dev, "system");
753 	if (IS_ERR(csi2->sysclk))
754 		return dev_err_probe(&pdev->dev, PTR_ERR(csi2->sysclk),
755 				     "Failed to get system clk\n");
756 
757 	vclk = clk_get(&pdev->dev, "video");
758 	if (IS_ERR(vclk))
759 		return dev_err_probe(&pdev->dev, PTR_ERR(vclk),
760 				     "Failed to get video clock\n");
761 	csi2->vclk_rate = clk_get_rate(vclk);
762 	clk_put(vclk);
763 
764 	csi2->dev = &pdev->dev;
765 
766 	platform_set_drvdata(pdev, csi2);
767 
768 	ret = rzg2l_csi2_parse_dt(csi2);
769 	if (ret)
770 		return ret;
771 
772 	pm_runtime_enable(&pdev->dev);
773 
774 	ret = rzg2l_validate_csi2_lanes(csi2);
775 	if (ret)
776 		goto error_pm;
777 
778 	csi2->subdev.dev = &pdev->dev;
779 	v4l2_subdev_init(&csi2->subdev, &rzg2l_csi2_subdev_ops);
780 	v4l2_set_subdevdata(&csi2->subdev, &pdev->dev);
781 	snprintf(csi2->subdev.name, sizeof(csi2->subdev.name),
782 		 "csi-%s", dev_name(&pdev->dev));
783 	csi2->subdev.flags = V4L2_SUBDEV_FL_HAS_DEVNODE;
784 
785 	csi2->subdev.entity.function = MEDIA_ENT_F_VID_IF_BRIDGE;
786 	csi2->subdev.entity.ops = &rzg2l_csi2_entity_ops;
787 
788 	csi2->pads[RZG2L_CSI2_SINK].flags = MEDIA_PAD_FL_SINK;
789 	/*
790 	 * TODO: RZ/G2L CSI2 supports 4 virtual channels, as virtual
791 	 * channels should be implemented by streams API which is under
792 	 * development lets hardcode to VC0 for now.
793 	 */
794 	csi2->pads[RZG2L_CSI2_SOURCE].flags = MEDIA_PAD_FL_SOURCE;
795 	ret = media_entity_pads_init(&csi2->subdev.entity, 2, csi2->pads);
796 	if (ret)
797 		goto error_pm;
798 
799 	ret = v4l2_subdev_init_finalize(&csi2->subdev);
800 	if (ret < 0)
801 		goto error_async;
802 
803 	ret = v4l2_async_register_subdev(&csi2->subdev);
804 	if (ret < 0)
805 		goto error_subdev;
806 
807 	return 0;
808 
809 error_subdev:
810 	v4l2_subdev_cleanup(&csi2->subdev);
811 error_async:
812 	v4l2_async_nf_unregister(&csi2->notifier);
813 	v4l2_async_nf_cleanup(&csi2->notifier);
814 	media_entity_cleanup(&csi2->subdev.entity);
815 error_pm:
816 	pm_runtime_disable(&pdev->dev);
817 
818 	return ret;
819 }
820 
821 static void rzg2l_csi2_remove(struct platform_device *pdev)
822 {
823 	struct rzg2l_csi2 *csi2 = platform_get_drvdata(pdev);
824 
825 	v4l2_async_nf_unregister(&csi2->notifier);
826 	v4l2_async_nf_cleanup(&csi2->notifier);
827 	v4l2_async_unregister_subdev(&csi2->subdev);
828 	v4l2_subdev_cleanup(&csi2->subdev);
829 	media_entity_cleanup(&csi2->subdev.entity);
830 	pm_runtime_disable(&pdev->dev);
831 }
832 
833 static int __maybe_unused rzg2l_csi2_pm_runtime_suspend(struct device *dev)
834 {
835 	struct rzg2l_csi2 *csi2 = dev_get_drvdata(dev);
836 
837 	reset_control_assert(csi2->presetn);
838 
839 	return 0;
840 }
841 
842 static int __maybe_unused rzg2l_csi2_pm_runtime_resume(struct device *dev)
843 {
844 	struct rzg2l_csi2 *csi2 = dev_get_drvdata(dev);
845 
846 	return reset_control_deassert(csi2->presetn);
847 }
848 
849 static const struct dev_pm_ops rzg2l_csi2_pm_ops = {
850 	SET_RUNTIME_PM_OPS(rzg2l_csi2_pm_runtime_suspend, rzg2l_csi2_pm_runtime_resume, NULL)
851 };
852 
853 static const struct of_device_id rzg2l_csi2_of_table[] = {
854 	{ .compatible = "renesas,rzg2l-csi2", },
855 	{ /* sentinel */ }
856 };
857 
858 static struct platform_driver rzg2l_csi2_pdrv = {
859 	.remove_new = rzg2l_csi2_remove,
860 	.probe	= rzg2l_csi2_probe,
861 	.driver	= {
862 		.name = "rzg2l-csi2",
863 		.of_match_table = rzg2l_csi2_of_table,
864 		.pm = &rzg2l_csi2_pm_ops,
865 	},
866 };
867 
868 module_platform_driver(rzg2l_csi2_pdrv);
869 
870 MODULE_AUTHOR("Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>");
871 MODULE_DESCRIPTION("Renesas RZ/G2L MIPI CSI2 receiver driver");
872 MODULE_LICENSE("GPL");
873