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-common.h>
16#include <media/v4l2-device.h>
17#include <media/v4l2-fwnode.h>
18#include <media/v4l2-mc.h>
19#include <media/v4l2-subdev.h>
20#include "imx-media.h"
21
22/*
23 * there must be 5 pads: 1 input pad from sensor, and
24 * the 4 virtual channel output pads
25 */
26#define CSI2_SINK_PAD       0
27#define CSI2_NUM_SINK_PADS  1
28#define CSI2_NUM_SRC_PADS   4
29#define CSI2_NUM_PADS       5
30
31/*
32 * The default maximum bit-rate per lane in Mbps, if the
33 * source subdev does not provide V4L2_CID_LINK_FREQ.
34 */
35#define CSI2_DEFAULT_MAX_MBPS 849
36
37struct csi2_dev {
38	struct device          *dev;
39	struct v4l2_subdev      sd;
40	struct v4l2_async_notifier notifier;
41	struct media_pad       pad[CSI2_NUM_PADS];
42	struct clk             *dphy_clk;
43	struct clk             *pllref_clk;
44	struct clk             *pix_clk; /* what is this? */
45	void __iomem           *base;
46
47	struct v4l2_subdev	*remote;
48	unsigned int		remote_pad;
49	unsigned short		data_lanes;
50
51	/* lock to protect all members below */
52	struct mutex lock;
53
54	struct v4l2_mbus_framefmt format_mbus;
55
56	int                     stream_count;
57	struct v4l2_subdev      *src_sd;
58	bool                    sink_linked[CSI2_NUM_SRC_PADS];
59};
60
61#define DEVICE_NAME "imx6-mipi-csi2"
62
63/* Register offsets */
64#define CSI2_VERSION            0x000
65#define CSI2_N_LANES            0x004
66#define CSI2_PHY_SHUTDOWNZ      0x008
67#define CSI2_DPHY_RSTZ          0x00c
68#define CSI2_RESETN             0x010
69#define CSI2_PHY_STATE          0x014
70#define PHY_STOPSTATEDATA_BIT   4
71#define PHY_STOPSTATEDATA(n)    BIT(PHY_STOPSTATEDATA_BIT + (n))
72#define PHY_RXCLKACTIVEHS       BIT(8)
73#define PHY_RXULPSCLKNOT        BIT(9)
74#define PHY_STOPSTATECLK        BIT(10)
75#define CSI2_DATA_IDS_1         0x018
76#define CSI2_DATA_IDS_2         0x01c
77#define CSI2_ERR1               0x020
78#define CSI2_ERR2               0x024
79#define CSI2_MSK1               0x028
80#define CSI2_MSK2               0x02c
81#define CSI2_PHY_TST_CTRL0      0x030
82#define PHY_TESTCLR		BIT(0)
83#define PHY_TESTCLK		BIT(1)
84#define CSI2_PHY_TST_CTRL1      0x034
85#define PHY_TESTEN		BIT(16)
86/*
87 * i.MX CSI2IPU Gasket registers follow. The CSI2IPU gasket is
88 * not part of the MIPI CSI-2 core, but its registers fall in the
89 * same register map range.
90 */
91#define CSI2IPU_GASKET		0xf00
92#define CSI2IPU_YUV422_YUYV	BIT(2)
93
94static inline struct csi2_dev *sd_to_dev(struct v4l2_subdev *sdev)
95{
96	return container_of(sdev, struct csi2_dev, sd);
97}
98
99static inline struct csi2_dev *notifier_to_dev(struct v4l2_async_notifier *n)
100{
101	return container_of(n, struct csi2_dev, notifier);
102}
103
104/*
105 * The required sequence of MIPI CSI-2 startup as specified in the i.MX6
106 * reference manual is as follows:
107 *
108 * 1. Deassert presetn signal (global reset).
109 *        It's not clear what this "global reset" signal is (maybe APB
110 *        global reset), but in any case this step would be probably
111 *        be carried out during driver load in csi2_probe().
112 *
113 * 2. Configure MIPI Camera Sensor to put all Tx lanes in LP-11 state.
114 *        This must be carried out by the MIPI sensor's s_power(ON) subdev
115 *        op.
116 *
117 * 3. D-PHY initialization.
118 * 4. CSI2 Controller programming (Set N_LANES, deassert PHY_SHUTDOWNZ,
119 *    deassert PHY_RSTZ, deassert CSI2_RESETN).
120 * 5. Read the PHY status register (PHY_STATE) to confirm that all data and
121 *    clock lanes of the D-PHY are in LP-11 state.
122 * 6. Configure the MIPI Camera Sensor to start transmitting a clock on the
123 *    D-PHY clock lane.
124 * 7. CSI2 Controller programming - Read the PHY status register (PHY_STATE)
125 *    to confirm that the D-PHY is receiving a clock on the D-PHY clock lane.
126 *
127 * All steps 3 through 7 are carried out by csi2_s_stream(ON) here. Step
128 * 6 is accomplished by calling the source subdev's s_stream(ON) between
129 * steps 5 and 7.
130 */
131
132static void csi2_enable(struct csi2_dev *csi2, bool enable)
133{
134	if (enable) {
135		writel(0x1, csi2->base + CSI2_PHY_SHUTDOWNZ);
136		writel(0x1, csi2->base + CSI2_DPHY_RSTZ);
137		writel(0x1, csi2->base + CSI2_RESETN);
138	} else {
139		writel(0x0, csi2->base + CSI2_PHY_SHUTDOWNZ);
140		writel(0x0, csi2->base + CSI2_DPHY_RSTZ);
141		writel(0x0, csi2->base + CSI2_RESETN);
142	}
143}
144
145static void csi2_set_lanes(struct csi2_dev *csi2, unsigned int lanes)
146{
147	writel(lanes - 1, csi2->base + CSI2_N_LANES);
148}
149
150static void dw_mipi_csi2_phy_write(struct csi2_dev *csi2,
151				   u32 test_code, u32 test_data)
152{
153	/* Clear PHY test interface */
154	writel(PHY_TESTCLR, csi2->base + CSI2_PHY_TST_CTRL0);
155	writel(0x0, csi2->base + CSI2_PHY_TST_CTRL1);
156	writel(0x0, csi2->base + CSI2_PHY_TST_CTRL0);
157
158	/* Raise test interface strobe signal */
159	writel(PHY_TESTCLK, csi2->base + CSI2_PHY_TST_CTRL0);
160
161	/* Configure address write on falling edge and lower strobe signal */
162	writel(PHY_TESTEN | test_code, csi2->base + CSI2_PHY_TST_CTRL1);
163	writel(0x0, csi2->base + CSI2_PHY_TST_CTRL0);
164
165	/* Configure data write on rising edge and raise strobe signal */
166	writel(test_data, csi2->base + CSI2_PHY_TST_CTRL1);
167	writel(PHY_TESTCLK, csi2->base + CSI2_PHY_TST_CTRL0);
168
169	/* Clear strobe signal */
170	writel(0x0, csi2->base + CSI2_PHY_TST_CTRL0);
171}
172
173/*
174 * This table is based on the table documented at
175 * https://community.nxp.com/docs/DOC-94312. It assumes
176 * a 27MHz D-PHY pll reference clock.
177 */
178static const struct {
179	u32 max_mbps;
180	u32 hsfreqrange_sel;
181} hsfreq_map[] = {
182	{ 90, 0x00}, {100, 0x20}, {110, 0x40}, {125, 0x02},
183	{140, 0x22}, {150, 0x42}, {160, 0x04}, {180, 0x24},
184	{200, 0x44}, {210, 0x06}, {240, 0x26}, {250, 0x46},
185	{270, 0x08}, {300, 0x28}, {330, 0x48}, {360, 0x2a},
186	{400, 0x4a}, {450, 0x0c}, {500, 0x2c}, {550, 0x0e},
187	{600, 0x2e}, {650, 0x10}, {700, 0x30}, {750, 0x12},
188	{800, 0x32}, {850, 0x14}, {900, 0x34}, {950, 0x54},
189	{1000, 0x74},
190};
191
192static int max_mbps_to_hsfreqrange_sel(u32 max_mbps)
193{
194	int i;
195
196	for (i = 0; i < ARRAY_SIZE(hsfreq_map); i++)
197		if (hsfreq_map[i].max_mbps > max_mbps)
198			return hsfreq_map[i].hsfreqrange_sel;
199
200	return -EINVAL;
201}
202
203static int csi2_dphy_init(struct csi2_dev *csi2)
204{
205	struct v4l2_ctrl *ctrl;
206	u32 mbps_per_lane;
207	int sel;
208
209	ctrl = v4l2_ctrl_find(csi2->src_sd->ctrl_handler,
210			      V4L2_CID_LINK_FREQ);
211	if (!ctrl)
212		mbps_per_lane = CSI2_DEFAULT_MAX_MBPS;
213	else
214		mbps_per_lane = DIV_ROUND_UP_ULL(2 * ctrl->qmenu_int[ctrl->val],
215						 USEC_PER_SEC);
216
217	sel = max_mbps_to_hsfreqrange_sel(mbps_per_lane);
218	if (sel < 0)
219		return sel;
220
221	dw_mipi_csi2_phy_write(csi2, 0x44, sel);
222
223	return 0;
224}
225
226/*
227 * Waits for ultra-low-power state on D-PHY clock lane. This is currently
228 * unused and may not be needed at all, but keep around just in case.
229 */
230static int __maybe_unused csi2_dphy_wait_ulp(struct csi2_dev *csi2)
231{
232	u32 reg;
233	int ret;
234
235	/* wait for ULP on clock lane */
236	ret = readl_poll_timeout(csi2->base + CSI2_PHY_STATE, reg,
237				 !(reg & PHY_RXULPSCLKNOT), 0, 500000);
238	if (ret) {
239		v4l2_err(&csi2->sd, "ULP timeout, phy_state = 0x%08x\n", reg);
240		return ret;
241	}
242
243	/* wait until no errors on bus */
244	ret = readl_poll_timeout(csi2->base + CSI2_ERR1, reg,
245				 reg == 0x0, 0, 500000);
246	if (ret) {
247		v4l2_err(&csi2->sd, "stable bus timeout, err1 = 0x%08x\n", reg);
248		return ret;
249	}
250
251	return 0;
252}
253
254/* Waits for low-power LP-11 state on data and clock lanes. */
255static void csi2_dphy_wait_stopstate(struct csi2_dev *csi2, unsigned int lanes)
256{
257	u32 mask, reg;
258	int ret;
259
260	mask = PHY_STOPSTATECLK | (((1 << lanes) - 1) << PHY_STOPSTATEDATA_BIT);
261
262	ret = readl_poll_timeout(csi2->base + CSI2_PHY_STATE, reg,
263				 (reg & mask) == mask, 0, 500000);
264	if (ret) {
265		v4l2_warn(&csi2->sd, "LP-11 wait timeout, likely a sensor driver bug, expect capture failures.\n");
266		v4l2_warn(&csi2->sd, "phy_state = 0x%08x\n", reg);
267	}
268}
269
270/* Wait for active clock on the clock lane. */
271static int csi2_dphy_wait_clock_lane(struct csi2_dev *csi2)
272{
273	u32 reg;
274	int ret;
275
276	ret = readl_poll_timeout(csi2->base + CSI2_PHY_STATE, reg,
277				 (reg & PHY_RXCLKACTIVEHS), 0, 500000);
278	if (ret) {
279		v4l2_err(&csi2->sd, "clock lane timeout, phy_state = 0x%08x\n",
280			 reg);
281		return ret;
282	}
283
284	return 0;
285}
286
287/* Setup the i.MX CSI2IPU Gasket */
288static void csi2ipu_gasket_init(struct csi2_dev *csi2)
289{
290	u32 reg = 0;
291
292	switch (csi2->format_mbus.code) {
293	case MEDIA_BUS_FMT_YUYV8_2X8:
294	case MEDIA_BUS_FMT_YUYV8_1X16:
295		reg = CSI2IPU_YUV422_YUYV;
296		break;
297	default:
298		break;
299	}
300
301	writel(reg, csi2->base + CSI2IPU_GASKET);
302}
303
304static int csi2_get_active_lanes(struct csi2_dev *csi2, unsigned int *lanes)
305{
306	struct v4l2_mbus_config mbus_config = { 0 };
307	int ret;
308
309	*lanes = csi2->data_lanes;
310
311	ret = v4l2_subdev_call(csi2->remote, pad, get_mbus_config,
312			       csi2->remote_pad, &mbus_config);
313	if (ret == -ENOIOCTLCMD) {
314		dev_dbg(csi2->dev, "No remote mbus configuration available\n");
315		return 0;
316	}
317
318	if (ret) {
319		dev_err(csi2->dev, "Failed to get remote mbus configuration\n");
320		return ret;
321	}
322
323	if (mbus_config.type != V4L2_MBUS_CSI2_DPHY) {
324		dev_err(csi2->dev, "Unsupported media bus type %u\n",
325			mbus_config.type);
326		return -EINVAL;
327	}
328
329	if (mbus_config.bus.mipi_csi2.num_data_lanes > csi2->data_lanes) {
330		dev_err(csi2->dev,
331			"Unsupported mbus config: too many data lanes %u\n",
332			mbus_config.bus.mipi_csi2.num_data_lanes);
333		return -EINVAL;
334	}
335
336	*lanes = mbus_config.bus.mipi_csi2.num_data_lanes;
337
338	return 0;
339}
340
341static int csi2_start(struct csi2_dev *csi2)
342{
343	unsigned int lanes;
344	int ret;
345
346	ret = clk_prepare_enable(csi2->pix_clk);
347	if (ret)
348		return ret;
349
350	/* setup the gasket */
351	csi2ipu_gasket_init(csi2);
352
353	/* Step 3 */
354	ret = csi2_dphy_init(csi2);
355	if (ret)
356		goto err_disable_clk;
357
358	ret = csi2_get_active_lanes(csi2, &lanes);
359	if (ret)
360		goto err_disable_clk;
361
362	/* Step 4 */
363	csi2_set_lanes(csi2, lanes);
364	csi2_enable(csi2, true);
365
366	/* Step 5 */
367	ret = v4l2_subdev_call(csi2->src_sd, video, pre_streamon,
368			       V4L2_SUBDEV_PRE_STREAMON_FL_MANUAL_LP);
369	if (ret && ret != -ENOIOCTLCMD)
370		goto err_assert_reset;
371	csi2_dphy_wait_stopstate(csi2, lanes);
372
373	/* Step 6 */
374	ret = v4l2_subdev_call(csi2->src_sd, video, s_stream, 1);
375	ret = (ret && ret != -ENOIOCTLCMD) ? ret : 0;
376	if (ret)
377		goto err_stop_lp11;
378
379	/* Step 7 */
380	ret = csi2_dphy_wait_clock_lane(csi2);
381	if (ret)
382		goto err_stop_upstream;
383
384	return 0;
385
386err_stop_upstream:
387	v4l2_subdev_call(csi2->src_sd, video, s_stream, 0);
388err_stop_lp11:
389	v4l2_subdev_call(csi2->src_sd, video, post_streamoff);
390err_assert_reset:
391	csi2_enable(csi2, false);
392err_disable_clk:
393	clk_disable_unprepare(csi2->pix_clk);
394	return ret;
395}
396
397static void csi2_stop(struct csi2_dev *csi2)
398{
399	/* stop upstream */
400	v4l2_subdev_call(csi2->src_sd, video, s_stream, 0);
401	v4l2_subdev_call(csi2->src_sd, video, post_streamoff);
402
403	csi2_enable(csi2, false);
404	clk_disable_unprepare(csi2->pix_clk);
405}
406
407/*
408 * V4L2 subdev operations.
409 */
410
411static int csi2_s_stream(struct v4l2_subdev *sd, int enable)
412{
413	struct csi2_dev *csi2 = sd_to_dev(sd);
414	int i, ret = 0;
415
416	mutex_lock(&csi2->lock);
417
418	if (!csi2->src_sd) {
419		ret = -EPIPE;
420		goto out;
421	}
422
423	for (i = 0; i < CSI2_NUM_SRC_PADS; i++) {
424		if (csi2->sink_linked[i])
425			break;
426	}
427	if (i >= CSI2_NUM_SRC_PADS) {
428		ret = -EPIPE;
429		goto out;
430	}
431
432	/*
433	 * enable/disable streaming only if stream_count is
434	 * going from 0 to 1 / 1 to 0.
435	 */
436	if (csi2->stream_count != !enable)
437		goto update_count;
438
439	dev_dbg(csi2->dev, "stream %s\n", enable ? "ON" : "OFF");
440	if (enable)
441		ret = csi2_start(csi2);
442	else
443		csi2_stop(csi2);
444	if (ret)
445		goto out;
446
447update_count:
448	csi2->stream_count += enable ? 1 : -1;
449	if (csi2->stream_count < 0)
450		csi2->stream_count = 0;
451out:
452	mutex_unlock(&csi2->lock);
453	return ret;
454}
455
456static int csi2_link_setup(struct media_entity *entity,
457			   const struct media_pad *local,
458			   const struct media_pad *remote, u32 flags)
459{
460	struct v4l2_subdev *sd = media_entity_to_v4l2_subdev(entity);
461	struct csi2_dev *csi2 = sd_to_dev(sd);
462	struct v4l2_subdev *remote_sd;
463	int ret = 0;
464
465	dev_dbg(csi2->dev, "link setup %s -> %s", remote->entity->name,
466		local->entity->name);
467
468	remote_sd = media_entity_to_v4l2_subdev(remote->entity);
469
470	mutex_lock(&csi2->lock);
471
472	if (local->flags & MEDIA_PAD_FL_SOURCE) {
473		if (flags & MEDIA_LNK_FL_ENABLED) {
474			if (csi2->sink_linked[local->index - 1]) {
475				ret = -EBUSY;
476				goto out;
477			}
478			csi2->sink_linked[local->index - 1] = true;
479		} else {
480			csi2->sink_linked[local->index - 1] = false;
481		}
482	} else {
483		if (flags & MEDIA_LNK_FL_ENABLED) {
484			if (csi2->src_sd) {
485				ret = -EBUSY;
486				goto out;
487			}
488			csi2->src_sd = remote_sd;
489		} else {
490			csi2->src_sd = NULL;
491		}
492	}
493
494out:
495	mutex_unlock(&csi2->lock);
496	return ret;
497}
498
499static struct v4l2_mbus_framefmt *
500__csi2_get_fmt(struct csi2_dev *csi2, struct v4l2_subdev_state *sd_state,
501	       unsigned int pad, enum v4l2_subdev_format_whence which)
502{
503	if (which == V4L2_SUBDEV_FORMAT_TRY)
504		return v4l2_subdev_state_get_format(sd_state, pad);
505	else
506		return &csi2->format_mbus;
507}
508
509static int csi2_get_fmt(struct v4l2_subdev *sd,
510			struct v4l2_subdev_state *sd_state,
511			struct v4l2_subdev_format *sdformat)
512{
513	struct csi2_dev *csi2 = sd_to_dev(sd);
514	struct v4l2_mbus_framefmt *fmt;
515
516	mutex_lock(&csi2->lock);
517
518	fmt = __csi2_get_fmt(csi2, sd_state, sdformat->pad, sdformat->which);
519
520	sdformat->format = *fmt;
521
522	mutex_unlock(&csi2->lock);
523
524	return 0;
525}
526
527static int csi2_set_fmt(struct v4l2_subdev *sd,
528			struct v4l2_subdev_state *sd_state,
529			struct v4l2_subdev_format *sdformat)
530{
531	struct csi2_dev *csi2 = sd_to_dev(sd);
532	struct v4l2_mbus_framefmt *fmt;
533	int ret = 0;
534
535	if (sdformat->pad >= CSI2_NUM_PADS)
536		return -EINVAL;
537
538	mutex_lock(&csi2->lock);
539
540	if (csi2->stream_count > 0) {
541		ret = -EBUSY;
542		goto out;
543	}
544
545	/* Output pads mirror active input pad, no limits on input pads */
546	if (sdformat->pad != CSI2_SINK_PAD)
547		sdformat->format = csi2->format_mbus;
548
549	fmt = __csi2_get_fmt(csi2, sd_state, sdformat->pad, sdformat->which);
550
551	*fmt = sdformat->format;
552out:
553	mutex_unlock(&csi2->lock);
554	return ret;
555}
556
557static int csi2_registered(struct v4l2_subdev *sd)
558{
559	struct csi2_dev *csi2 = sd_to_dev(sd);
560
561	/* set a default mbus format  */
562	return imx_media_init_mbus_fmt(&csi2->format_mbus,
563				      IMX_MEDIA_DEF_PIX_WIDTH,
564				      IMX_MEDIA_DEF_PIX_HEIGHT, 0,
565				      V4L2_FIELD_NONE, NULL);
566}
567
568/* --------------- CORE OPS --------------- */
569
570static int csi2_log_status(struct v4l2_subdev *sd)
571{
572	struct csi2_dev *csi2 = sd_to_dev(sd);
573
574	v4l2_info(sd, "-----MIPI CSI status-----\n");
575	v4l2_info(sd, "VERSION: 0x%x\n",
576		  readl(csi2->base + CSI2_VERSION));
577	v4l2_info(sd, "N_LANES: 0x%x\n",
578		  readl(csi2->base + CSI2_N_LANES));
579	v4l2_info(sd, "PHY_SHUTDOWNZ: 0x%x\n",
580		  readl(csi2->base + CSI2_PHY_SHUTDOWNZ));
581	v4l2_info(sd, "DPHY_RSTZ: 0x%x\n",
582		  readl(csi2->base + CSI2_DPHY_RSTZ));
583	v4l2_info(sd, "RESETN: 0x%x\n",
584		  readl(csi2->base + CSI2_RESETN));
585	v4l2_info(sd, "PHY_STATE: 0x%x\n",
586		  readl(csi2->base + CSI2_PHY_STATE));
587	v4l2_info(sd, "DATA_IDS_1: 0x%x\n",
588		  readl(csi2->base + CSI2_DATA_IDS_1));
589	v4l2_info(sd, "DATA_IDS_2: 0x%x\n",
590		  readl(csi2->base + CSI2_DATA_IDS_2));
591	v4l2_info(sd, "ERR1: 0x%x\n",
592		  readl(csi2->base + CSI2_ERR1));
593	v4l2_info(sd, "ERR2: 0x%x\n",
594		  readl(csi2->base + CSI2_ERR2));
595	v4l2_info(sd, "MSK1: 0x%x\n",
596		  readl(csi2->base + CSI2_MSK1));
597	v4l2_info(sd, "MSK2: 0x%x\n",
598		  readl(csi2->base + CSI2_MSK2));
599	v4l2_info(sd, "PHY_TST_CTRL0: 0x%x\n",
600		  readl(csi2->base + CSI2_PHY_TST_CTRL0));
601	v4l2_info(sd, "PHY_TST_CTRL1: 0x%x\n",
602		  readl(csi2->base + CSI2_PHY_TST_CTRL1));
603
604	return 0;
605}
606
607static const struct v4l2_subdev_core_ops csi2_core_ops = {
608	.log_status = csi2_log_status,
609};
610
611static const struct media_entity_operations csi2_entity_ops = {
612	.link_setup = csi2_link_setup,
613	.link_validate = v4l2_subdev_link_validate,
614	.get_fwnode_pad = v4l2_subdev_get_fwnode_pad_1_to_1,
615};
616
617static const struct v4l2_subdev_video_ops csi2_video_ops = {
618	.s_stream = csi2_s_stream,
619};
620
621static const struct v4l2_subdev_pad_ops csi2_pad_ops = {
622	.get_fmt = csi2_get_fmt,
623	.set_fmt = csi2_set_fmt,
624};
625
626static const struct v4l2_subdev_ops csi2_subdev_ops = {
627	.core = &csi2_core_ops,
628	.video = &csi2_video_ops,
629	.pad = &csi2_pad_ops,
630};
631
632static const struct v4l2_subdev_internal_ops csi2_internal_ops = {
633	.init_state = imx_media_init_state,
634	.registered = csi2_registered,
635};
636
637static int csi2_notify_bound(struct v4l2_async_notifier *notifier,
638			     struct v4l2_subdev *sd,
639			     struct v4l2_async_connection *asd)
640{
641	struct csi2_dev *csi2 = notifier_to_dev(notifier);
642	struct media_pad *sink = &csi2->sd.entity.pads[CSI2_SINK_PAD];
643	int pad;
644
645	pad = media_entity_get_fwnode_pad(&sd->entity, asd->match.fwnode,
646					  MEDIA_PAD_FL_SOURCE);
647	if (pad < 0) {
648		dev_err(csi2->dev, "Failed to find pad for %s\n", sd->name);
649		return pad;
650	}
651
652	csi2->remote = sd;
653	csi2->remote_pad = pad;
654
655	dev_dbg(csi2->dev, "Bound %s pad: %d\n", sd->name, pad);
656
657	return v4l2_create_fwnode_links_to_pad(sd, sink, 0);
658}
659
660static void csi2_notify_unbind(struct v4l2_async_notifier *notifier,
661			       struct v4l2_subdev *sd,
662			       struct v4l2_async_connection *asd)
663{
664	struct csi2_dev *csi2 = notifier_to_dev(notifier);
665
666	csi2->remote = NULL;
667}
668
669static const struct v4l2_async_notifier_operations csi2_notify_ops = {
670	.bound = csi2_notify_bound,
671	.unbind = csi2_notify_unbind,
672};
673
674static int csi2_async_register(struct csi2_dev *csi2)
675{
676	struct v4l2_fwnode_endpoint vep = {
677		.bus_type = V4L2_MBUS_CSI2_DPHY,
678	};
679	struct v4l2_async_connection *asd;
680	struct fwnode_handle *ep;
681	int ret;
682
683	v4l2_async_subdev_nf_init(&csi2->notifier, &csi2->sd);
684
685	ep = fwnode_graph_get_endpoint_by_id(dev_fwnode(csi2->dev), 0, 0,
686					     FWNODE_GRAPH_ENDPOINT_NEXT);
687	if (!ep)
688		return -ENOTCONN;
689
690	ret = v4l2_fwnode_endpoint_parse(ep, &vep);
691	if (ret)
692		goto err_parse;
693
694	csi2->data_lanes = vep.bus.mipi_csi2.num_data_lanes;
695
696	dev_dbg(csi2->dev, "data lanes: %d\n", vep.bus.mipi_csi2.num_data_lanes);
697	dev_dbg(csi2->dev, "flags: 0x%08x\n", vep.bus.mipi_csi2.flags);
698
699	asd = v4l2_async_nf_add_fwnode_remote(&csi2->notifier, ep,
700					      struct v4l2_async_connection);
701	fwnode_handle_put(ep);
702
703	if (IS_ERR(asd))
704		return PTR_ERR(asd);
705
706	csi2->notifier.ops = &csi2_notify_ops;
707
708	ret = v4l2_async_nf_register(&csi2->notifier);
709	if (ret)
710		return ret;
711
712	return v4l2_async_register_subdev(&csi2->sd);
713
714err_parse:
715	fwnode_handle_put(ep);
716	return ret;
717}
718
719static int csi2_probe(struct platform_device *pdev)
720{
721	struct csi2_dev *csi2;
722	struct resource *res;
723	int i, ret;
724
725	csi2 = devm_kzalloc(&pdev->dev, sizeof(*csi2), GFP_KERNEL);
726	if (!csi2)
727		return -ENOMEM;
728
729	csi2->dev = &pdev->dev;
730
731	v4l2_subdev_init(&csi2->sd, &csi2_subdev_ops);
732	v4l2_set_subdevdata(&csi2->sd, &pdev->dev);
733	csi2->sd.internal_ops = &csi2_internal_ops;
734	csi2->sd.entity.ops = &csi2_entity_ops;
735	csi2->sd.dev = &pdev->dev;
736	csi2->sd.owner = THIS_MODULE;
737	csi2->sd.flags = V4L2_SUBDEV_FL_HAS_DEVNODE;
738	strscpy(csi2->sd.name, DEVICE_NAME, sizeof(csi2->sd.name));
739	csi2->sd.entity.function = MEDIA_ENT_F_VID_IF_BRIDGE;
740	csi2->sd.grp_id = IMX_MEDIA_GRP_ID_CSI2;
741
742	for (i = 0; i < CSI2_NUM_PADS; i++) {
743		csi2->pad[i].flags = (i == CSI2_SINK_PAD) ?
744		MEDIA_PAD_FL_SINK : MEDIA_PAD_FL_SOURCE;
745	}
746
747	ret = media_entity_pads_init(&csi2->sd.entity, CSI2_NUM_PADS,
748				     csi2->pad);
749	if (ret)
750		return ret;
751
752	csi2->pllref_clk = devm_clk_get(&pdev->dev, "ref");
753	if (IS_ERR(csi2->pllref_clk)) {
754		v4l2_err(&csi2->sd, "failed to get pll reference clock\n");
755		return PTR_ERR(csi2->pllref_clk);
756	}
757
758	csi2->dphy_clk = devm_clk_get(&pdev->dev, "dphy");
759	if (IS_ERR(csi2->dphy_clk)) {
760		v4l2_err(&csi2->sd, "failed to get dphy clock\n");
761		return PTR_ERR(csi2->dphy_clk);
762	}
763
764	csi2->pix_clk = devm_clk_get(&pdev->dev, "pix");
765	if (IS_ERR(csi2->pix_clk)) {
766		v4l2_err(&csi2->sd, "failed to get pixel clock\n");
767		return PTR_ERR(csi2->pix_clk);
768	}
769
770	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
771	if (!res) {
772		v4l2_err(&csi2->sd, "failed to get platform resources\n");
773		return -ENODEV;
774	}
775
776	csi2->base = devm_ioremap(&pdev->dev, res->start, PAGE_SIZE);
777	if (!csi2->base)
778		return -ENOMEM;
779
780	mutex_init(&csi2->lock);
781
782	ret = clk_prepare_enable(csi2->pllref_clk);
783	if (ret) {
784		v4l2_err(&csi2->sd, "failed to enable pllref_clk\n");
785		goto rmmutex;
786	}
787
788	ret = clk_prepare_enable(csi2->dphy_clk);
789	if (ret) {
790		v4l2_err(&csi2->sd, "failed to enable dphy_clk\n");
791		goto pllref_off;
792	}
793
794	platform_set_drvdata(pdev, &csi2->sd);
795
796	ret = csi2_async_register(csi2);
797	if (ret)
798		goto clean_notifier;
799
800	return 0;
801
802clean_notifier:
803	v4l2_async_nf_unregister(&csi2->notifier);
804	v4l2_async_nf_cleanup(&csi2->notifier);
805	clk_disable_unprepare(csi2->dphy_clk);
806pllref_off:
807	clk_disable_unprepare(csi2->pllref_clk);
808rmmutex:
809	mutex_destroy(&csi2->lock);
810	return ret;
811}
812
813static void csi2_remove(struct platform_device *pdev)
814{
815	struct v4l2_subdev *sd = platform_get_drvdata(pdev);
816	struct csi2_dev *csi2 = sd_to_dev(sd);
817
818	v4l2_async_nf_unregister(&csi2->notifier);
819	v4l2_async_nf_cleanup(&csi2->notifier);
820	v4l2_async_unregister_subdev(sd);
821	clk_disable_unprepare(csi2->dphy_clk);
822	clk_disable_unprepare(csi2->pllref_clk);
823	mutex_destroy(&csi2->lock);
824	media_entity_cleanup(&sd->entity);
825}
826
827static const struct of_device_id csi2_dt_ids[] = {
828	{ .compatible = "fsl,imx6-mipi-csi2", },
829	{ /* sentinel */ }
830};
831MODULE_DEVICE_TABLE(of, csi2_dt_ids);
832
833static struct platform_driver csi2_driver = {
834	.driver = {
835		.name = DEVICE_NAME,
836		.of_match_table = csi2_dt_ids,
837	},
838	.probe = csi2_probe,
839	.remove_new = csi2_remove,
840};
841
842module_platform_driver(csi2_driver);
843
844MODULE_DESCRIPTION("i.MX5/6 MIPI CSI-2 Receiver driver");
845MODULE_AUTHOR("Steve Longerbeam <steve_longerbeam@mentor.com>");
846MODULE_LICENSE("GPL");
847