1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * MIPI CSI-2 Receiver Subdev for Freescale i.MX6 SOC.
4  *
5  * Copyright (c) 2012-2017 Mentor Graphics Inc.
6  */
7 #include <linux/clk.h>
8 #include <linux/interrupt.h>
9 #include <linux/io.h>
10 #include <linux/iopoll.h>
11 #include <linux/irq.h>
12 #include <linux/module.h>
13 #include <linux/of_graph.h>
14 #include <linux/platform_device.h>
15 #include <media/v4l2-device.h>
16 #include <media/v4l2-fwnode.h>
17 #include <media/v4l2-mc.h>
18 #include <media/v4l2-subdev.h>
19 #include "imx-media.h"
20 
21 /*
22  * there must be 5 pads: 1 input pad from sensor, and
23  * the 4 virtual channel output pads
24  */
25 #define CSI2_SINK_PAD       0
26 #define CSI2_NUM_SINK_PADS  1
27 #define CSI2_NUM_SRC_PADS   4
28 #define CSI2_NUM_PADS       5
29 
30 /*
31  * The default maximum bit-rate per lane in Mbps, if the
32  * source subdev does not provide V4L2_CID_LINK_FREQ.
33  */
34 #define CSI2_DEFAULT_MAX_MBPS 849
35 
36 struct csi2_dev {
37 	struct device          *dev;
38 	struct v4l2_subdev      sd;
39 	struct v4l2_async_notifier notifier;
40 	struct media_pad       pad[CSI2_NUM_PADS];
41 	struct clk             *dphy_clk;
42 	struct clk             *pllref_clk;
43 	struct clk             *pix_clk; /* what is this? */
44 	void __iomem           *base;
45 
46 	struct v4l2_subdev	*remote;
47 	unsigned int		remote_pad;
48 	unsigned short		data_lanes;
49 
50 	/* lock to protect all members below */
51 	struct mutex lock;
52 
53 	struct v4l2_mbus_framefmt format_mbus;
54 
55 	int                     stream_count;
56 	struct v4l2_subdev      *src_sd;
57 	bool                    sink_linked[CSI2_NUM_SRC_PADS];
58 };
59 
60 #define DEVICE_NAME "imx6-mipi-csi2"
61 
62 /* Register offsets */
63 #define CSI2_VERSION            0x000
64 #define CSI2_N_LANES            0x004
65 #define CSI2_PHY_SHUTDOWNZ      0x008
66 #define CSI2_DPHY_RSTZ          0x00c
67 #define CSI2_RESETN             0x010
68 #define CSI2_PHY_STATE          0x014
69 #define PHY_STOPSTATEDATA_BIT   4
70 #define PHY_STOPSTATEDATA(n)    BIT(PHY_STOPSTATEDATA_BIT + (n))
71 #define PHY_RXCLKACTIVEHS       BIT(8)
72 #define PHY_RXULPSCLKNOT        BIT(9)
73 #define PHY_STOPSTATECLK        BIT(10)
74 #define CSI2_DATA_IDS_1         0x018
75 #define CSI2_DATA_IDS_2         0x01c
76 #define CSI2_ERR1               0x020
77 #define CSI2_ERR2               0x024
78 #define CSI2_MSK1               0x028
79 #define CSI2_MSK2               0x02c
80 #define CSI2_PHY_TST_CTRL0      0x030
81 #define PHY_TESTCLR		BIT(0)
82 #define PHY_TESTCLK		BIT(1)
83 #define CSI2_PHY_TST_CTRL1      0x034
84 #define PHY_TESTEN		BIT(16)
85 /*
86  * i.MX CSI2IPU Gasket registers follow. The CSI2IPU gasket is
87  * not part of the MIPI CSI-2 core, but its registers fall in the
88  * same register map range.
89  */
90 #define CSI2IPU_GASKET		0xf00
91 #define CSI2IPU_YUV422_YUYV	BIT(2)
92 
93 static inline struct csi2_dev *sd_to_dev(struct v4l2_subdev *sdev)
94 {
95 	return container_of(sdev, struct csi2_dev, sd);
96 }
97 
98 static inline struct csi2_dev *notifier_to_dev(struct v4l2_async_notifier *n)
99 {
100 	return container_of(n, struct csi2_dev, notifier);
101 }
102 
103 /*
104  * The required sequence of MIPI CSI-2 startup as specified in the i.MX6
105  * reference manual is as follows:
106  *
107  * 1. Deassert presetn signal (global reset).
108  *        It's not clear what this "global reset" signal is (maybe APB
109  *        global reset), but in any case this step would be probably
110  *        be carried out during driver load in csi2_probe().
111  *
112  * 2. Configure MIPI Camera Sensor to put all Tx lanes in LP-11 state.
113  *        This must be carried out by the MIPI sensor's s_power(ON) subdev
114  *        op.
115  *
116  * 3. D-PHY initialization.
117  * 4. CSI2 Controller programming (Set N_LANES, deassert PHY_SHUTDOWNZ,
118  *    deassert PHY_RSTZ, deassert CSI2_RESETN).
119  * 5. Read the PHY status register (PHY_STATE) to confirm that all data and
120  *    clock lanes of the D-PHY are in LP-11 state.
121  * 6. Configure the MIPI Camera Sensor to start transmitting a clock on the
122  *    D-PHY clock lane.
123  * 7. CSI2 Controller programming - Read the PHY status register (PHY_STATE)
124  *    to confirm that the D-PHY is receiving a clock on the D-PHY clock lane.
125  *
126  * All steps 3 through 7 are carried out by csi2_s_stream(ON) here. Step
127  * 6 is accomplished by calling the source subdev's s_stream(ON) between
128  * steps 5 and 7.
129  */
130 
131 static void csi2_enable(struct csi2_dev *csi2, bool enable)
132 {
133 	if (enable) {
134 		writel(0x1, csi2->base + CSI2_PHY_SHUTDOWNZ);
135 		writel(0x1, csi2->base + CSI2_DPHY_RSTZ);
136 		writel(0x1, csi2->base + CSI2_RESETN);
137 	} else {
138 		writel(0x0, csi2->base + CSI2_PHY_SHUTDOWNZ);
139 		writel(0x0, csi2->base + CSI2_DPHY_RSTZ);
140 		writel(0x0, csi2->base + CSI2_RESETN);
141 	}
142 }
143 
144 static void csi2_set_lanes(struct csi2_dev *csi2, unsigned int lanes)
145 {
146 	writel(lanes - 1, csi2->base + CSI2_N_LANES);
147 }
148 
149 static void dw_mipi_csi2_phy_write(struct csi2_dev *csi2,
150 				   u32 test_code, u32 test_data)
151 {
152 	/* Clear PHY test interface */
153 	writel(PHY_TESTCLR, csi2->base + CSI2_PHY_TST_CTRL0);
154 	writel(0x0, csi2->base + CSI2_PHY_TST_CTRL1);
155 	writel(0x0, csi2->base + CSI2_PHY_TST_CTRL0);
156 
157 	/* Raise test interface strobe signal */
158 	writel(PHY_TESTCLK, csi2->base + CSI2_PHY_TST_CTRL0);
159 
160 	/* Configure address write on falling edge and lower strobe signal */
161 	writel(PHY_TESTEN | test_code, csi2->base + CSI2_PHY_TST_CTRL1);
162 	writel(0x0, csi2->base + CSI2_PHY_TST_CTRL0);
163 
164 	/* Configure data write on rising edge and raise strobe signal */
165 	writel(test_data, csi2->base + CSI2_PHY_TST_CTRL1);
166 	writel(PHY_TESTCLK, csi2->base + CSI2_PHY_TST_CTRL0);
167 
168 	/* Clear strobe signal */
169 	writel(0x0, csi2->base + CSI2_PHY_TST_CTRL0);
170 }
171 
172 /*
173  * This table is based on the table documented at
174  * https://community.nxp.com/docs/DOC-94312. It assumes
175  * a 27MHz D-PHY pll reference clock.
176  */
177 static const struct {
178 	u32 max_mbps;
179 	u32 hsfreqrange_sel;
180 } hsfreq_map[] = {
181 	{ 90, 0x00}, {100, 0x20}, {110, 0x40}, {125, 0x02},
182 	{140, 0x22}, {150, 0x42}, {160, 0x04}, {180, 0x24},
183 	{200, 0x44}, {210, 0x06}, {240, 0x26}, {250, 0x46},
184 	{270, 0x08}, {300, 0x28}, {330, 0x48}, {360, 0x2a},
185 	{400, 0x4a}, {450, 0x0c}, {500, 0x2c}, {550, 0x0e},
186 	{600, 0x2e}, {650, 0x10}, {700, 0x30}, {750, 0x12},
187 	{800, 0x32}, {850, 0x14}, {900, 0x34}, {950, 0x54},
188 	{1000, 0x74},
189 };
190 
191 static int max_mbps_to_hsfreqrange_sel(u32 max_mbps)
192 {
193 	int i;
194 
195 	for (i = 0; i < ARRAY_SIZE(hsfreq_map); i++)
196 		if (hsfreq_map[i].max_mbps > max_mbps)
197 			return hsfreq_map[i].hsfreqrange_sel;
198 
199 	return -EINVAL;
200 }
201 
202 static int csi2_dphy_init(struct csi2_dev *csi2)
203 {
204 	struct v4l2_ctrl *ctrl;
205 	u32 mbps_per_lane;
206 	int sel;
207 
208 	ctrl = v4l2_ctrl_find(csi2->src_sd->ctrl_handler,
209 			      V4L2_CID_LINK_FREQ);
210 	if (!ctrl)
211 		mbps_per_lane = CSI2_DEFAULT_MAX_MBPS;
212 	else
213 		mbps_per_lane = DIV_ROUND_UP_ULL(2 * ctrl->qmenu_int[ctrl->val],
214 						 USEC_PER_SEC);
215 
216 	sel = max_mbps_to_hsfreqrange_sel(mbps_per_lane);
217 	if (sel < 0)
218 		return sel;
219 
220 	dw_mipi_csi2_phy_write(csi2, 0x44, sel);
221 
222 	return 0;
223 }
224 
225 /*
226  * Waits for ultra-low-power state on D-PHY clock lane. This is currently
227  * unused and may not be needed at all, but keep around just in case.
228  */
229 static int __maybe_unused csi2_dphy_wait_ulp(struct csi2_dev *csi2)
230 {
231 	u32 reg;
232 	int ret;
233 
234 	/* wait for ULP on clock lane */
235 	ret = readl_poll_timeout(csi2->base + CSI2_PHY_STATE, reg,
236 				 !(reg & PHY_RXULPSCLKNOT), 0, 500000);
237 	if (ret) {
238 		v4l2_err(&csi2->sd, "ULP timeout, phy_state = 0x%08x\n", reg);
239 		return ret;
240 	}
241 
242 	/* wait until no errors on bus */
243 	ret = readl_poll_timeout(csi2->base + CSI2_ERR1, reg,
244 				 reg == 0x0, 0, 500000);
245 	if (ret) {
246 		v4l2_err(&csi2->sd, "stable bus timeout, err1 = 0x%08x\n", reg);
247 		return ret;
248 	}
249 
250 	return 0;
251 }
252 
253 /* Waits for low-power LP-11 state on data and clock lanes. */
254 static void csi2_dphy_wait_stopstate(struct csi2_dev *csi2, unsigned int lanes)
255 {
256 	u32 mask, reg;
257 	int ret;
258 
259 	mask = PHY_STOPSTATECLK | (((1 << lanes) - 1) << PHY_STOPSTATEDATA_BIT);
260 
261 	ret = readl_poll_timeout(csi2->base + CSI2_PHY_STATE, reg,
262 				 (reg & mask) == mask, 0, 500000);
263 	if (ret) {
264 		v4l2_warn(&csi2->sd, "LP-11 wait timeout, likely a sensor driver bug, expect capture failures.\n");
265 		v4l2_warn(&csi2->sd, "phy_state = 0x%08x\n", reg);
266 	}
267 }
268 
269 /* Wait for active clock on the clock lane. */
270 static int csi2_dphy_wait_clock_lane(struct csi2_dev *csi2)
271 {
272 	u32 reg;
273 	int ret;
274 
275 	ret = readl_poll_timeout(csi2->base + CSI2_PHY_STATE, reg,
276 				 (reg & PHY_RXCLKACTIVEHS), 0, 500000);
277 	if (ret) {
278 		v4l2_err(&csi2->sd, "clock lane timeout, phy_state = 0x%08x\n",
279 			 reg);
280 		return ret;
281 	}
282 
283 	return 0;
284 }
285 
286 /* Setup the i.MX CSI2IPU Gasket */
287 static void csi2ipu_gasket_init(struct csi2_dev *csi2)
288 {
289 	u32 reg = 0;
290 
291 	switch (csi2->format_mbus.code) {
292 	case MEDIA_BUS_FMT_YUYV8_2X8:
293 	case MEDIA_BUS_FMT_YUYV8_1X16:
294 		reg = CSI2IPU_YUV422_YUYV;
295 		break;
296 	default:
297 		break;
298 	}
299 
300 	writel(reg, csi2->base + CSI2IPU_GASKET);
301 }
302 
303 static int csi2_get_active_lanes(struct csi2_dev *csi2, unsigned int *lanes)
304 {
305 	struct v4l2_mbus_config mbus_config = { 0 };
306 	int ret;
307 
308 	*lanes = csi2->data_lanes;
309 
310 	ret = v4l2_subdev_call(csi2->remote, pad, get_mbus_config,
311 			       csi2->remote_pad, &mbus_config);
312 	if (ret == -ENOIOCTLCMD) {
313 		dev_dbg(csi2->dev, "No remote mbus configuration available\n");
314 		return 0;
315 	}
316 
317 	if (ret) {
318 		dev_err(csi2->dev, "Failed to get remote mbus configuration\n");
319 		return ret;
320 	}
321 
322 	if (mbus_config.type != V4L2_MBUS_CSI2_DPHY) {
323 		dev_err(csi2->dev, "Unsupported media bus type %u\n",
324 			mbus_config.type);
325 		return -EINVAL;
326 	}
327 
328 	if (mbus_config.bus.mipi_csi2.num_data_lanes > csi2->data_lanes) {
329 		dev_err(csi2->dev,
330 			"Unsupported mbus config: too many data lanes %u\n",
331 			mbus_config.bus.mipi_csi2.num_data_lanes);
332 		return -EINVAL;
333 	}
334 
335 	*lanes = mbus_config.bus.mipi_csi2.num_data_lanes;
336 
337 	return 0;
338 }
339 
340 static int csi2_start(struct csi2_dev *csi2)
341 {
342 	unsigned int lanes;
343 	int ret;
344 
345 	ret = clk_prepare_enable(csi2->pix_clk);
346 	if (ret)
347 		return ret;
348 
349 	/* setup the gasket */
350 	csi2ipu_gasket_init(csi2);
351 
352 	/* Step 3 */
353 	ret = csi2_dphy_init(csi2);
354 	if (ret)
355 		goto err_disable_clk;
356 
357 	ret = csi2_get_active_lanes(csi2, &lanes);
358 	if (ret)
359 		goto err_disable_clk;
360 
361 	/* Step 4 */
362 	csi2_set_lanes(csi2, lanes);
363 	csi2_enable(csi2, true);
364 
365 	/* Step 5 */
366 	ret = v4l2_subdev_call(csi2->src_sd, video, pre_streamon,
367 			       V4L2_SUBDEV_PRE_STREAMON_FL_MANUAL_LP);
368 	if (ret && ret != -ENOIOCTLCMD)
369 		goto err_assert_reset;
370 	csi2_dphy_wait_stopstate(csi2, lanes);
371 
372 	/* Step 6 */
373 	ret = v4l2_subdev_call(csi2->src_sd, video, s_stream, 1);
374 	ret = (ret && ret != -ENOIOCTLCMD) ? ret : 0;
375 	if (ret)
376 		goto err_stop_lp11;
377 
378 	/* Step 7 */
379 	ret = csi2_dphy_wait_clock_lane(csi2);
380 	if (ret)
381 		goto err_stop_upstream;
382 
383 	return 0;
384 
385 err_stop_upstream:
386 	v4l2_subdev_call(csi2->src_sd, video, s_stream, 0);
387 err_stop_lp11:
388 	v4l2_subdev_call(csi2->src_sd, video, post_streamoff);
389 err_assert_reset:
390 	csi2_enable(csi2, false);
391 err_disable_clk:
392 	clk_disable_unprepare(csi2->pix_clk);
393 	return ret;
394 }
395 
396 static void csi2_stop(struct csi2_dev *csi2)
397 {
398 	/* stop upstream */
399 	v4l2_subdev_call(csi2->src_sd, video, s_stream, 0);
400 	v4l2_subdev_call(csi2->src_sd, video, post_streamoff);
401 
402 	csi2_enable(csi2, false);
403 	clk_disable_unprepare(csi2->pix_clk);
404 }
405 
406 /*
407  * V4L2 subdev operations.
408  */
409 
410 static int csi2_s_stream(struct v4l2_subdev *sd, int enable)
411 {
412 	struct csi2_dev *csi2 = sd_to_dev(sd);
413 	int i, ret = 0;
414 
415 	mutex_lock(&csi2->lock);
416 
417 	if (!csi2->src_sd) {
418 		ret = -EPIPE;
419 		goto out;
420 	}
421 
422 	for (i = 0; i < CSI2_NUM_SRC_PADS; i++) {
423 		if (csi2->sink_linked[i])
424 			break;
425 	}
426 	if (i >= CSI2_NUM_SRC_PADS) {
427 		ret = -EPIPE;
428 		goto out;
429 	}
430 
431 	/*
432 	 * enable/disable streaming only if stream_count is
433 	 * going from 0 to 1 / 1 to 0.
434 	 */
435 	if (csi2->stream_count != !enable)
436 		goto update_count;
437 
438 	dev_dbg(csi2->dev, "stream %s\n", enable ? "ON" : "OFF");
439 	if (enable)
440 		ret = csi2_start(csi2);
441 	else
442 		csi2_stop(csi2);
443 	if (ret)
444 		goto out;
445 
446 update_count:
447 	csi2->stream_count += enable ? 1 : -1;
448 	if (csi2->stream_count < 0)
449 		csi2->stream_count = 0;
450 out:
451 	mutex_unlock(&csi2->lock);
452 	return ret;
453 }
454 
455 static int csi2_link_setup(struct media_entity *entity,
456 			   const struct media_pad *local,
457 			   const struct media_pad *remote, u32 flags)
458 {
459 	struct v4l2_subdev *sd = media_entity_to_v4l2_subdev(entity);
460 	struct csi2_dev *csi2 = sd_to_dev(sd);
461 	struct v4l2_subdev *remote_sd;
462 	int ret = 0;
463 
464 	dev_dbg(csi2->dev, "link setup %s -> %s", remote->entity->name,
465 		local->entity->name);
466 
467 	remote_sd = media_entity_to_v4l2_subdev(remote->entity);
468 
469 	mutex_lock(&csi2->lock);
470 
471 	if (local->flags & MEDIA_PAD_FL_SOURCE) {
472 		if (flags & MEDIA_LNK_FL_ENABLED) {
473 			if (csi2->sink_linked[local->index - 1]) {
474 				ret = -EBUSY;
475 				goto out;
476 			}
477 			csi2->sink_linked[local->index - 1] = true;
478 		} else {
479 			csi2->sink_linked[local->index - 1] = false;
480 		}
481 	} else {
482 		if (flags & MEDIA_LNK_FL_ENABLED) {
483 			if (csi2->src_sd) {
484 				ret = -EBUSY;
485 				goto out;
486 			}
487 			csi2->src_sd = remote_sd;
488 		} else {
489 			csi2->src_sd = NULL;
490 		}
491 	}
492 
493 out:
494 	mutex_unlock(&csi2->lock);
495 	return ret;
496 }
497 
498 static struct v4l2_mbus_framefmt *
499 __csi2_get_fmt(struct csi2_dev *csi2, struct v4l2_subdev_state *sd_state,
500 	       unsigned int pad, enum v4l2_subdev_format_whence which)
501 {
502 	if (which == V4L2_SUBDEV_FORMAT_TRY)
503 		return v4l2_subdev_get_try_format(&csi2->sd, sd_state, pad);
504 	else
505 		return &csi2->format_mbus;
506 }
507 
508 static int csi2_get_fmt(struct v4l2_subdev *sd,
509 			struct v4l2_subdev_state *sd_state,
510 			struct v4l2_subdev_format *sdformat)
511 {
512 	struct csi2_dev *csi2 = sd_to_dev(sd);
513 	struct v4l2_mbus_framefmt *fmt;
514 
515 	mutex_lock(&csi2->lock);
516 
517 	fmt = __csi2_get_fmt(csi2, sd_state, sdformat->pad, sdformat->which);
518 
519 	sdformat->format = *fmt;
520 
521 	mutex_unlock(&csi2->lock);
522 
523 	return 0;
524 }
525 
526 static int csi2_set_fmt(struct v4l2_subdev *sd,
527 			struct v4l2_subdev_state *sd_state,
528 			struct v4l2_subdev_format *sdformat)
529 {
530 	struct csi2_dev *csi2 = sd_to_dev(sd);
531 	struct v4l2_mbus_framefmt *fmt;
532 	int ret = 0;
533 
534 	if (sdformat->pad >= CSI2_NUM_PADS)
535 		return -EINVAL;
536 
537 	mutex_lock(&csi2->lock);
538 
539 	if (csi2->stream_count > 0) {
540 		ret = -EBUSY;
541 		goto out;
542 	}
543 
544 	/* Output pads mirror active input pad, no limits on input pads */
545 	if (sdformat->pad != CSI2_SINK_PAD)
546 		sdformat->format = csi2->format_mbus;
547 
548 	fmt = __csi2_get_fmt(csi2, sd_state, sdformat->pad, sdformat->which);
549 
550 	*fmt = sdformat->format;
551 out:
552 	mutex_unlock(&csi2->lock);
553 	return ret;
554 }
555 
556 static int csi2_registered(struct v4l2_subdev *sd)
557 {
558 	struct csi2_dev *csi2 = sd_to_dev(sd);
559 
560 	/* set a default mbus format  */
561 	return imx_media_init_mbus_fmt(&csi2->format_mbus,
562 				      IMX_MEDIA_DEF_PIX_WIDTH,
563 				      IMX_MEDIA_DEF_PIX_HEIGHT, 0,
564 				      V4L2_FIELD_NONE, NULL);
565 }
566 
567 static const struct media_entity_operations csi2_entity_ops = {
568 	.link_setup = csi2_link_setup,
569 	.link_validate = v4l2_subdev_link_validate,
570 	.get_fwnode_pad = v4l2_subdev_get_fwnode_pad_1_to_1,
571 };
572 
573 static const struct v4l2_subdev_video_ops csi2_video_ops = {
574 	.s_stream = csi2_s_stream,
575 };
576 
577 static const struct v4l2_subdev_pad_ops csi2_pad_ops = {
578 	.init_cfg = imx_media_init_cfg,
579 	.get_fmt = csi2_get_fmt,
580 	.set_fmt = csi2_set_fmt,
581 };
582 
583 static const struct v4l2_subdev_ops csi2_subdev_ops = {
584 	.video = &csi2_video_ops,
585 	.pad = &csi2_pad_ops,
586 };
587 
588 static const struct v4l2_subdev_internal_ops csi2_internal_ops = {
589 	.registered = csi2_registered,
590 };
591 
592 static int csi2_notify_bound(struct v4l2_async_notifier *notifier,
593 			     struct v4l2_subdev *sd,
594 			     struct v4l2_async_subdev *asd)
595 {
596 	struct csi2_dev *csi2 = notifier_to_dev(notifier);
597 	struct media_pad *sink = &csi2->sd.entity.pads[CSI2_SINK_PAD];
598 	int pad;
599 
600 	pad = media_entity_get_fwnode_pad(&sd->entity, asd->match.fwnode,
601 					  MEDIA_PAD_FL_SOURCE);
602 	if (pad < 0) {
603 		dev_err(csi2->dev, "Failed to find pad for %s\n", sd->name);
604 		return pad;
605 	}
606 
607 	csi2->remote = sd;
608 	csi2->remote_pad = pad;
609 
610 	dev_dbg(csi2->dev, "Bound %s pad: %d\n", sd->name, pad);
611 
612 	return v4l2_create_fwnode_links_to_pad(sd, sink, 0);
613 }
614 
615 static void csi2_notify_unbind(struct v4l2_async_notifier *notifier,
616 			       struct v4l2_subdev *sd,
617 			       struct v4l2_async_subdev *asd)
618 {
619 	struct csi2_dev *csi2 = notifier_to_dev(notifier);
620 
621 	csi2->remote = NULL;
622 }
623 
624 static const struct v4l2_async_notifier_operations csi2_notify_ops = {
625 	.bound = csi2_notify_bound,
626 	.unbind = csi2_notify_unbind,
627 };
628 
629 static int csi2_async_register(struct csi2_dev *csi2)
630 {
631 	struct v4l2_fwnode_endpoint vep = {
632 		.bus_type = V4L2_MBUS_CSI2_DPHY,
633 	};
634 	struct v4l2_async_subdev *asd;
635 	struct fwnode_handle *ep;
636 	int ret;
637 
638 	v4l2_async_nf_init(&csi2->notifier);
639 
640 	ep = fwnode_graph_get_endpoint_by_id(dev_fwnode(csi2->dev), 0, 0,
641 					     FWNODE_GRAPH_ENDPOINT_NEXT);
642 	if (!ep)
643 		return -ENOTCONN;
644 
645 	ret = v4l2_fwnode_endpoint_parse(ep, &vep);
646 	if (ret)
647 		goto err_parse;
648 
649 	csi2->data_lanes = vep.bus.mipi_csi2.num_data_lanes;
650 
651 	dev_dbg(csi2->dev, "data lanes: %d\n", vep.bus.mipi_csi2.num_data_lanes);
652 	dev_dbg(csi2->dev, "flags: 0x%08x\n", vep.bus.mipi_csi2.flags);
653 
654 	asd = v4l2_async_nf_add_fwnode_remote(&csi2->notifier, ep,
655 					      struct v4l2_async_subdev);
656 	fwnode_handle_put(ep);
657 
658 	if (IS_ERR(asd))
659 		return PTR_ERR(asd);
660 
661 	csi2->notifier.ops = &csi2_notify_ops;
662 
663 	ret = v4l2_async_subdev_nf_register(&csi2->sd, &csi2->notifier);
664 	if (ret)
665 		return ret;
666 
667 	return v4l2_async_register_subdev(&csi2->sd);
668 
669 err_parse:
670 	fwnode_handle_put(ep);
671 	return ret;
672 }
673 
674 static int csi2_probe(struct platform_device *pdev)
675 {
676 	struct csi2_dev *csi2;
677 	struct resource *res;
678 	int i, ret;
679 
680 	csi2 = devm_kzalloc(&pdev->dev, sizeof(*csi2), GFP_KERNEL);
681 	if (!csi2)
682 		return -ENOMEM;
683 
684 	csi2->dev = &pdev->dev;
685 
686 	v4l2_subdev_init(&csi2->sd, &csi2_subdev_ops);
687 	v4l2_set_subdevdata(&csi2->sd, &pdev->dev);
688 	csi2->sd.internal_ops = &csi2_internal_ops;
689 	csi2->sd.entity.ops = &csi2_entity_ops;
690 	csi2->sd.dev = &pdev->dev;
691 	csi2->sd.owner = THIS_MODULE;
692 	csi2->sd.flags = V4L2_SUBDEV_FL_HAS_DEVNODE;
693 	strscpy(csi2->sd.name, DEVICE_NAME, sizeof(csi2->sd.name));
694 	csi2->sd.entity.function = MEDIA_ENT_F_VID_IF_BRIDGE;
695 	csi2->sd.grp_id = IMX_MEDIA_GRP_ID_CSI2;
696 
697 	for (i = 0; i < CSI2_NUM_PADS; i++) {
698 		csi2->pad[i].flags = (i == CSI2_SINK_PAD) ?
699 		MEDIA_PAD_FL_SINK : MEDIA_PAD_FL_SOURCE;
700 	}
701 
702 	ret = media_entity_pads_init(&csi2->sd.entity, CSI2_NUM_PADS,
703 				     csi2->pad);
704 	if (ret)
705 		return ret;
706 
707 	csi2->pllref_clk = devm_clk_get(&pdev->dev, "ref");
708 	if (IS_ERR(csi2->pllref_clk)) {
709 		v4l2_err(&csi2->sd, "failed to get pll reference clock\n");
710 		return PTR_ERR(csi2->pllref_clk);
711 	}
712 
713 	csi2->dphy_clk = devm_clk_get(&pdev->dev, "dphy");
714 	if (IS_ERR(csi2->dphy_clk)) {
715 		v4l2_err(&csi2->sd, "failed to get dphy clock\n");
716 		return PTR_ERR(csi2->dphy_clk);
717 	}
718 
719 	csi2->pix_clk = devm_clk_get(&pdev->dev, "pix");
720 	if (IS_ERR(csi2->pix_clk)) {
721 		v4l2_err(&csi2->sd, "failed to get pixel clock\n");
722 		return PTR_ERR(csi2->pix_clk);
723 	}
724 
725 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
726 	if (!res) {
727 		v4l2_err(&csi2->sd, "failed to get platform resources\n");
728 		return -ENODEV;
729 	}
730 
731 	csi2->base = devm_ioremap(&pdev->dev, res->start, PAGE_SIZE);
732 	if (!csi2->base)
733 		return -ENOMEM;
734 
735 	mutex_init(&csi2->lock);
736 
737 	ret = clk_prepare_enable(csi2->pllref_clk);
738 	if (ret) {
739 		v4l2_err(&csi2->sd, "failed to enable pllref_clk\n");
740 		goto rmmutex;
741 	}
742 
743 	ret = clk_prepare_enable(csi2->dphy_clk);
744 	if (ret) {
745 		v4l2_err(&csi2->sd, "failed to enable dphy_clk\n");
746 		goto pllref_off;
747 	}
748 
749 	platform_set_drvdata(pdev, &csi2->sd);
750 
751 	ret = csi2_async_register(csi2);
752 	if (ret)
753 		goto clean_notifier;
754 
755 	return 0;
756 
757 clean_notifier:
758 	v4l2_async_nf_unregister(&csi2->notifier);
759 	v4l2_async_nf_cleanup(&csi2->notifier);
760 	clk_disable_unprepare(csi2->dphy_clk);
761 pllref_off:
762 	clk_disable_unprepare(csi2->pllref_clk);
763 rmmutex:
764 	mutex_destroy(&csi2->lock);
765 	return ret;
766 }
767 
768 static int csi2_remove(struct platform_device *pdev)
769 {
770 	struct v4l2_subdev *sd = platform_get_drvdata(pdev);
771 	struct csi2_dev *csi2 = sd_to_dev(sd);
772 
773 	v4l2_async_nf_unregister(&csi2->notifier);
774 	v4l2_async_nf_cleanup(&csi2->notifier);
775 	v4l2_async_unregister_subdev(sd);
776 	clk_disable_unprepare(csi2->dphy_clk);
777 	clk_disable_unprepare(csi2->pllref_clk);
778 	mutex_destroy(&csi2->lock);
779 	media_entity_cleanup(&sd->entity);
780 
781 	return 0;
782 }
783 
784 static const struct of_device_id csi2_dt_ids[] = {
785 	{ .compatible = "fsl,imx6-mipi-csi2", },
786 	{ /* sentinel */ }
787 };
788 MODULE_DEVICE_TABLE(of, csi2_dt_ids);
789 
790 static struct platform_driver csi2_driver = {
791 	.driver = {
792 		.name = DEVICE_NAME,
793 		.of_match_table = csi2_dt_ids,
794 	},
795 	.probe = csi2_probe,
796 	.remove = csi2_remove,
797 };
798 
799 module_platform_driver(csi2_driver);
800 
801 MODULE_DESCRIPTION("i.MX5/6 MIPI CSI-2 Receiver driver");
802 MODULE_AUTHOR("Steve Longerbeam <steve_longerbeam@mentor.com>");
803 MODULE_LICENSE("GPL");
804