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1// SPDX-License-Identifier: GPL-2.0+2/*3 * Maxim MAX9286 GMSL Deserializer Driver4 *5 * Copyright (C) 2017-2019 Jacopo Mondi6 * Copyright (C) 2017-2019 Kieran Bingham7 * Copyright (C) 2017-2019 Laurent Pinchart8 * Copyright (C) 2017-2019 Niklas Söderlund9 * Copyright (C) 2016 Renesas Electronics Corporation10 * Copyright (C) 2015 Cogent Embedded, Inc.11 */12 13#include <linux/delay.h>14#include <linux/device.h>15#include <linux/fwnode.h>16#include <linux/gpio/consumer.h>17#include <linux/gpio/driver.h>18#include <linux/gpio/machine.h>19#include <linux/i2c.h>20#include <linux/i2c-mux.h>21#include <linux/module.h>22#include <linux/of_graph.h>23#include <linux/regulator/consumer.h>24#include <linux/slab.h>25 26#include <media/v4l2-async.h>27#include <media/v4l2-ctrls.h>28#include <media/v4l2-device.h>29#include <media/v4l2-fwnode.h>30#include <media/v4l2-subdev.h>31 32/* Register 0x00 */33#define MAX9286_MSTLINKSEL_AUTO		(7 << 5)34#define MAX9286_MSTLINKSEL(n)		((n) << 5)35#define MAX9286_EN_VS_GEN		BIT(4)36#define MAX9286_LINKEN(n)		(1 << (n))37/* Register 0x01 */38#define MAX9286_FSYNCMODE_ECU		(3 << 6)39#define MAX9286_FSYNCMODE_EXT		(2 << 6)40#define MAX9286_FSYNCMODE_INT_OUT	(1 << 6)41#define MAX9286_FSYNCMODE_INT_HIZ	(0 << 6)42#define MAX9286_GPIEN			BIT(5)43#define MAX9286_ENLMO_RSTFSYNC		BIT(2)44#define MAX9286_FSYNCMETH_AUTO		(2 << 0)45#define MAX9286_FSYNCMETH_SEMI_AUTO	(1 << 0)46#define MAX9286_FSYNCMETH_MANUAL	(0 << 0)47#define MAX9286_REG_FSYNC_PERIOD_L	0x0648#define MAX9286_REG_FSYNC_PERIOD_M	0x0749#define MAX9286_REG_FSYNC_PERIOD_H	0x0850/* Register 0x0a */51#define MAX9286_FWDCCEN(n)		(1 << ((n) + 4))52#define MAX9286_REVCCEN(n)		(1 << (n))53/* Register 0x0c */54#define MAX9286_HVEN			BIT(7)55#define MAX9286_EDC_6BIT_HAMMING	(2 << 5)56#define MAX9286_EDC_6BIT_CRC		(1 << 5)57#define MAX9286_EDC_1BIT_PARITY		(0 << 5)58#define MAX9286_DESEL			BIT(4)59#define MAX9286_INVVS			BIT(3)60#define MAX9286_INVHS			BIT(2)61#define MAX9286_HVSRC_D0		(2 << 0)62#define MAX9286_HVSRC_D14		(1 << 0)63#define MAX9286_HVSRC_D18		(0 << 0)64/* Register 0x0f */65#define MAX9286_0X0F_RESERVED		BIT(3)66/* Register 0x12 */67#define MAX9286_CSILANECNT(n)		(((n) - 1) << 6)68#define MAX9286_CSIDBL			BIT(5)69#define MAX9286_DBL			BIT(4)70#define MAX9286_DATATYPE_USER_8BIT	(11 << 0)71#define MAX9286_DATATYPE_USER_YUV_12BIT	(10 << 0)72#define MAX9286_DATATYPE_USER_24BIT	(9 << 0)73#define MAX9286_DATATYPE_RAW14		(8 << 0)74#define MAX9286_DATATYPE_RAW12		(7 << 0)75#define MAX9286_DATATYPE_RAW10		(6 << 0)76#define MAX9286_DATATYPE_RAW8		(5 << 0)77#define MAX9286_DATATYPE_YUV422_10BIT	(4 << 0)78#define MAX9286_DATATYPE_YUV422_8BIT	(3 << 0)79#define MAX9286_DATATYPE_RGB555		(2 << 0)80#define MAX9286_DATATYPE_RGB565		(1 << 0)81#define MAX9286_DATATYPE_RGB888		(0 << 0)82/* Register 0x15 */83#define MAX9286_CSI_IMAGE_TYP		BIT(7)84#define MAX9286_VC(n)			((n) << 5)85#define MAX9286_VCTYPE			BIT(4)86#define MAX9286_CSIOUTEN		BIT(3)87#define MAX9286_SWP_ENDIAN		BIT(2)88#define MAX9286_EN_CCBSYB_CLK_STR	BIT(1)89#define MAX9286_EN_GPI_CCBSYB		BIT(0)90/* Register 0x1b */91#define MAX9286_SWITCHIN(n)		(1 << ((n) + 4))92#define MAX9286_ENEQ(n)			(1 << (n))93/* Register 0x1c */94#define MAX9286_HIGHIMM(n)		BIT((n) + 4)95#define MAX9286_I2CSEL			BIT(2)96#define MAX9286_HIBW			BIT(1)97#define MAX9286_BWS			BIT(0)98/* Register 0x27 */99#define MAX9286_LOCKED			BIT(7)100/* Register 0x31 */101#define MAX9286_FSYNC_LOCKED		BIT(6)102/* Register 0x34 */103#define MAX9286_I2CLOCACK		BIT(7)104#define MAX9286_I2CSLVSH_1046NS_469NS	(3 << 5)105#define MAX9286_I2CSLVSH_938NS_352NS	(2 << 5)106#define MAX9286_I2CSLVSH_469NS_234NS	(1 << 5)107#define MAX9286_I2CSLVSH_352NS_117NS	(0 << 5)108#define MAX9286_I2CMSTBT_837KBPS	(7 << 2)109#define MAX9286_I2CMSTBT_533KBPS	(6 << 2)110#define MAX9286_I2CMSTBT_339KBPS	(5 << 2)111#define MAX9286_I2CMSTBT_173KBPS	(4 << 2)112#define MAX9286_I2CMSTBT_105KBPS	(3 << 2)113#define MAX9286_I2CMSTBT_84KBPS		(2 << 2)114#define MAX9286_I2CMSTBT_28KBPS		(1 << 2)115#define MAX9286_I2CMSTBT_8KBPS		(0 << 2)116#define MAX9286_I2CSLVTO_NONE		(3 << 0)117#define MAX9286_I2CSLVTO_1024US		(2 << 0)118#define MAX9286_I2CSLVTO_256US		(1 << 0)119#define MAX9286_I2CSLVTO_64US		(0 << 0)120/* Register 0x3b */121#define MAX9286_REV_TRF(n)		((n) << 4)122#define MAX9286_REV_AMP(n)		((((n) - 30) / 10) << 1) /* in mV */123#define MAX9286_REV_AMP_X		BIT(0)124#define MAX9286_REV_AMP_HIGH		170125/* Register 0x3f */126#define MAX9286_EN_REV_CFG		BIT(6)127#define MAX9286_REV_FLEN(n)		((n) - 20)128/* Register 0x49 */129#define MAX9286_VIDEO_DETECT_MASK	0x0f130/* Register 0x69 */131#define MAX9286_LFLTBMONMASKED		BIT(7)132#define MAX9286_LOCKMONMASKED		BIT(6)133#define MAX9286_AUTOCOMBACKEN		BIT(5)134#define MAX9286_AUTOMASKEN		BIT(4)135#define MAX9286_MASKLINK(n)		((n) << 0)136 137/*138 * The sink and source pads are created to match the OF graph port numbers so139 * that their indexes can be used interchangeably.140 */141#define MAX9286_NUM_GMSL		4142#define MAX9286_N_SINKS			4143#define MAX9286_N_PADS			5144#define MAX9286_SRC_PAD			4145 146struct max9286_format_info {147	u32 code;148	u8 datatype;149};150 151struct max9286_i2c_speed {152	u32 rate;153	u8 mstbt;154};155 156struct max9286_source {157	struct v4l2_subdev *sd;158	struct fwnode_handle *fwnode;159	struct regulator *regulator;160};161 162struct max9286_asd {163	struct v4l2_async_connection base;164	struct max9286_source *source;165};166 167static inline struct max9286_asd *168to_max9286_asd(struct v4l2_async_connection *asd)169{170	return container_of(asd, struct max9286_asd, base);171}172 173struct max9286_priv {174	struct i2c_client *client;175	struct gpio_desc *gpiod_pwdn;176	struct v4l2_subdev sd;177	struct media_pad pads[MAX9286_N_PADS];178	struct regulator *regulator;179 180	struct gpio_chip gpio;181	u8 gpio_state;182 183	struct i2c_mux_core *mux;184	unsigned int mux_channel;185	bool mux_open;186 187	/* The initial reverse control channel amplitude. */188	u32 init_rev_chan_mv;189	u32 rev_chan_mv;190	u8 i2c_mstbt;191	u32 bus_width;192 193	bool use_gpio_poc;194	u32 gpio_poc[2];195 196	struct v4l2_ctrl_handler ctrls;197	struct v4l2_ctrl *pixelrate_ctrl;198	unsigned int pixelrate;199 200	unsigned int nsources;201	unsigned int source_mask;202	unsigned int route_mask;203	unsigned int bound_sources;204	unsigned int csi2_data_lanes;205	struct max9286_source sources[MAX9286_NUM_GMSL];206	struct v4l2_async_notifier notifier;207};208 209static struct max9286_source *next_source(struct max9286_priv *priv,210					  struct max9286_source *source)211{212	if (!source)213		source = &priv->sources[0];214	else215		source++;216 217	for (; source < &priv->sources[MAX9286_NUM_GMSL]; source++) {218		if (source->fwnode)219			return source;220	}221 222	return NULL;223}224 225#define for_each_source(priv, source) \226	for ((source) = NULL; ((source) = next_source((priv), (source))); )227 228#define to_index(priv, source) ((source) - &(priv)->sources[0])229 230static inline struct max9286_priv *sd_to_max9286(struct v4l2_subdev *sd)231{232	return container_of(sd, struct max9286_priv, sd);233}234 235static const struct max9286_format_info max9286_formats[] = {236	{237		.code = MEDIA_BUS_FMT_UYVY8_1X16,238		.datatype = MAX9286_DATATYPE_YUV422_8BIT,239	}, {240		.code = MEDIA_BUS_FMT_VYUY8_1X16,241		.datatype = MAX9286_DATATYPE_YUV422_8BIT,242	}, {243		.code = MEDIA_BUS_FMT_YUYV8_1X16,244		.datatype = MAX9286_DATATYPE_YUV422_8BIT,245	}, {246		.code = MEDIA_BUS_FMT_YVYU8_1X16,247		.datatype = MAX9286_DATATYPE_YUV422_8BIT,248	}, {249		.code = MEDIA_BUS_FMT_SBGGR12_1X12,250		.datatype = MAX9286_DATATYPE_RAW12,251	}, {252		.code = MEDIA_BUS_FMT_SGBRG12_1X12,253		.datatype = MAX9286_DATATYPE_RAW12,254	}, {255		.code = MEDIA_BUS_FMT_SGRBG12_1X12,256		.datatype = MAX9286_DATATYPE_RAW12,257	}, {258		.code = MEDIA_BUS_FMT_SRGGB12_1X12,259		.datatype = MAX9286_DATATYPE_RAW12,260	},261};262 263static const struct max9286_i2c_speed max9286_i2c_speeds[] = {264	{ .rate =   8470, .mstbt = MAX9286_I2CMSTBT_8KBPS },265	{ .rate =  28300, .mstbt = MAX9286_I2CMSTBT_28KBPS },266	{ .rate =  84700, .mstbt = MAX9286_I2CMSTBT_84KBPS },267	{ .rate = 105000, .mstbt = MAX9286_I2CMSTBT_105KBPS },268	{ .rate = 173000, .mstbt = MAX9286_I2CMSTBT_173KBPS },269	{ .rate = 339000, .mstbt = MAX9286_I2CMSTBT_339KBPS },270	{ .rate = 533000, .mstbt = MAX9286_I2CMSTBT_533KBPS },271	{ .rate = 837000, .mstbt = MAX9286_I2CMSTBT_837KBPS },272};273 274/* -----------------------------------------------------------------------------275 * I2C IO276 */277 278static int max9286_read(struct max9286_priv *priv, u8 reg)279{280	int ret;281 282	ret = i2c_smbus_read_byte_data(priv->client, reg);283	if (ret < 0)284		dev_err(&priv->client->dev,285			"%s: register 0x%02x read failed (%d)\n",286			__func__, reg, ret);287 288	return ret;289}290 291static int max9286_write(struct max9286_priv *priv, u8 reg, u8 val)292{293	int ret;294 295	ret = i2c_smbus_write_byte_data(priv->client, reg, val);296	if (ret < 0)297		dev_err(&priv->client->dev,298			"%s: register 0x%02x write failed (%d)\n",299			__func__, reg, ret);300 301	return ret;302}303 304/* -----------------------------------------------------------------------------305 * I2C Multiplexer306 */307 308static void max9286_i2c_mux_configure(struct max9286_priv *priv, u8 conf)309{310	max9286_write(priv, 0x0a, conf);311 312	/*313	 * We must sleep after any change to the forward or reverse channel314	 * configuration.315	 */316	usleep_range(3000, 5000);317}318 319static void max9286_i2c_mux_open(struct max9286_priv *priv)320{321	/* Open all channels on the MAX9286 */322	max9286_i2c_mux_configure(priv, 0xff);323 324	priv->mux_open = true;325}326 327static void max9286_i2c_mux_close(struct max9286_priv *priv)328{329	/*330	 * Ensure that both the forward and reverse channel are disabled on the331	 * mux, and that the channel ID is invalidated to ensure we reconfigure332	 * on the next max9286_i2c_mux_select() call.333	 */334	max9286_i2c_mux_configure(priv, 0x00);335 336	priv->mux_open = false;337	priv->mux_channel = -1;338}339 340static int max9286_i2c_mux_select(struct i2c_mux_core *muxc, u32 chan)341{342	struct max9286_priv *priv = i2c_mux_priv(muxc);343 344	/* Channel select is disabled when configured in the opened state. */345	if (priv->mux_open)346		return 0;347 348	if (priv->mux_channel == chan)349		return 0;350 351	priv->mux_channel = chan;352 353	max9286_i2c_mux_configure(priv, MAX9286_FWDCCEN(chan) |354					MAX9286_REVCCEN(chan));355 356	return 0;357}358 359static int max9286_i2c_mux_init(struct max9286_priv *priv)360{361	struct max9286_source *source;362	int ret;363 364	if (!i2c_check_functionality(priv->client->adapter,365				     I2C_FUNC_SMBUS_WRITE_BYTE_DATA))366		return -ENODEV;367 368	priv->mux = i2c_mux_alloc(priv->client->adapter, &priv->client->dev,369				  priv->nsources, 0, I2C_MUX_LOCKED,370				  max9286_i2c_mux_select, NULL);371	if (!priv->mux)372		return -ENOMEM;373 374	priv->mux->priv = priv;375 376	for_each_source(priv, source) {377		unsigned int index = to_index(priv, source);378 379		ret = i2c_mux_add_adapter(priv->mux, 0, index);380		if (ret < 0)381			goto error;382	}383 384	return 0;385 386error:387	i2c_mux_del_adapters(priv->mux);388	return ret;389}390 391static void max9286_configure_i2c(struct max9286_priv *priv, bool localack)392{393	u8 config = MAX9286_I2CSLVSH_469NS_234NS | MAX9286_I2CSLVTO_1024US |394		    priv->i2c_mstbt;395 396	if (localack)397		config |= MAX9286_I2CLOCACK;398 399	max9286_write(priv, 0x34, config);400	usleep_range(3000, 5000);401}402 403static void max9286_reverse_channel_setup(struct max9286_priv *priv,404					  unsigned int chan_amplitude)405{406	u8 chan_config;407 408	if (priv->rev_chan_mv == chan_amplitude)409		return;410 411	priv->rev_chan_mv = chan_amplitude;412 413	/* Reverse channel transmission time: default to 1. */414	chan_config = MAX9286_REV_TRF(1);415 416	/*417	 * Reverse channel setup.418	 *419	 * - Enable custom reverse channel configuration (through register 0x3f)420	 *   and set the first pulse length to 35 clock cycles.421	 * - Adjust reverse channel amplitude: values > 130 are programmed422	 *   using the additional +100mV REV_AMP_X boost flag423	 */424	max9286_write(priv, 0x3f, MAX9286_EN_REV_CFG | MAX9286_REV_FLEN(35));425 426	if (chan_amplitude > 100) {427		/* It is not possible to express values (100 < x < 130) */428		chan_amplitude = max(30U, chan_amplitude - 100);429		chan_config |= MAX9286_REV_AMP_X;430	}431	max9286_write(priv, 0x3b, chan_config | MAX9286_REV_AMP(chan_amplitude));432	usleep_range(2000, 2500);433}434 435/*436 * max9286_check_video_links() - Make sure video links are detected and locked437 *438 * Performs safety checks on video link status. Make sure they are detected439 * and all enabled links are locked.440 *441 * Returns 0 for success, -EIO for errors.442 */443static int max9286_check_video_links(struct max9286_priv *priv)444{445	unsigned int i;446	int ret;447 448	/*449	 * Make sure valid video links are detected.450	 * The delay is not characterized in de-serializer manual, wait up451	 * to 5 ms.452	 */453	for (i = 0; i < 10; i++) {454		ret = max9286_read(priv, 0x49);455		if (ret < 0)456			return -EIO;457 458		if ((ret & MAX9286_VIDEO_DETECT_MASK) == priv->source_mask)459			break;460 461		usleep_range(350, 500);462	}463 464	if (i == 10) {465		dev_err(&priv->client->dev,466			"Unable to detect video links: 0x%02x\n", ret);467		return -EIO;468	}469 470	/* Make sure all enabled links are locked (4ms max). */471	for (i = 0; i < 10; i++) {472		ret = max9286_read(priv, 0x27);473		if (ret < 0)474			return -EIO;475 476		if (ret & MAX9286_LOCKED)477			break;478 479		usleep_range(350, 450);480	}481 482	if (i == 10) {483		dev_err(&priv->client->dev, "Not all enabled links locked\n");484		return -EIO;485	}486 487	return 0;488}489 490/*491 * max9286_check_config_link() - Detect and wait for configuration links492 *493 * Determine if the configuration channel is up and settled for a link.494 *495 * Returns 0 for success, -EIO for errors.496 */497static int max9286_check_config_link(struct max9286_priv *priv,498				     unsigned int source_mask)499{500	unsigned int conflink_mask = (source_mask & 0x0f) << 4;501	unsigned int i;502	int ret;503 504	/*505	 * Make sure requested configuration links are detected.506	 * The delay is not characterized in the chip manual: wait up507	 * to 5 milliseconds.508	 */509	for (i = 0; i < 10; i++) {510		ret = max9286_read(priv, 0x49);511		if (ret < 0)512			return -EIO;513 514		ret &= 0xf0;515		if (ret == conflink_mask)516			break;517 518		usleep_range(350, 500);519	}520 521	if (ret != conflink_mask) {522		dev_err(&priv->client->dev,523			"Unable to detect configuration links: 0x%02x expected 0x%02x\n",524			ret, conflink_mask);525		return -EIO;526	}527 528	dev_info(&priv->client->dev,529		 "Successfully detected configuration links after %u loops: 0x%02x\n",530		 i, conflink_mask);531 532	return 0;533}534 535static void max9286_set_video_format(struct max9286_priv *priv,536				     const struct v4l2_mbus_framefmt *format)537{538	const struct max9286_format_info *info = NULL;539	unsigned int i;540 541	for (i = 0; i < ARRAY_SIZE(max9286_formats); ++i) {542		if (max9286_formats[i].code == format->code) {543			info = &max9286_formats[i];544			break;545		}546	}547 548	if (WARN_ON(!info))549		return;550 551	/*552	 * Video format setup: disable CSI output, set VC according to Link553	 * number, enable I2C clock stretching when CCBSY is low, enable CCBSY554	 * in external GPI-to-GPO mode.555	 */556	max9286_write(priv, 0x15, MAX9286_VCTYPE | MAX9286_EN_CCBSYB_CLK_STR |557		      MAX9286_EN_GPI_CCBSYB);558 559	/* Enable CSI-2 Lane D0-D3 only, DBL mode. */560	max9286_write(priv, 0x12, MAX9286_CSIDBL | MAX9286_DBL |561		      MAX9286_CSILANECNT(priv->csi2_data_lanes) |562		      info->datatype);563 564	/*565	 * Enable HS/VS encoding, use HS as line valid source, use D14/15 for566	 * HS/VS, invert VS.567	 */568	max9286_write(priv, 0x0c, MAX9286_HVEN | MAX9286_DESEL |569		      MAX9286_INVVS | MAX9286_HVSRC_D14);570}571 572static void max9286_set_fsync_period(struct max9286_priv *priv,573				     struct v4l2_subdev_state *state)574{575	const struct v4l2_fract *interval;576	u32 fsync;577 578	interval = v4l2_subdev_state_get_interval(state, MAX9286_SRC_PAD);579	if (!interval->numerator || !interval->denominator) {580		/*581		 * Special case, a null interval enables automatic FRAMESYNC582		 * mode. FRAMESYNC is taken from the slowest link.583		 */584		max9286_write(priv, 0x01, MAX9286_FSYNCMODE_INT_HIZ |585			      MAX9286_FSYNCMETH_AUTO);586		return;587	}588 589	/*590	 * Manual FRAMESYNC591	 *592	 * The FRAMESYNC generator is configured with a period expressed as a593	 * number of PCLK periods.594	 */595	fsync = div_u64((u64)priv->pixelrate * interval->numerator,596			interval->denominator);597 598	dev_dbg(&priv->client->dev, "fsync period %u (pclk %u)\n", fsync,599		priv->pixelrate);600 601	max9286_write(priv, 0x01, MAX9286_FSYNCMODE_INT_OUT |602		      MAX9286_FSYNCMETH_MANUAL);603 604	max9286_write(priv, 0x06, (fsync >> 0) & 0xff);605	max9286_write(priv, 0x07, (fsync >> 8) & 0xff);606	max9286_write(priv, 0x08, (fsync >> 16) & 0xff);607}608 609/* -----------------------------------------------------------------------------610 * V4L2 Subdev611 */612 613static int max9286_set_pixelrate(struct max9286_priv *priv)614{615	struct max9286_source *source = NULL;616	u64 pixelrate = 0;617 618	for_each_source(priv, source) {619		struct v4l2_ctrl *ctrl;620		u64 source_rate = 0;621 622		/* Pixel rate is mandatory to be reported by sources. */623		ctrl = v4l2_ctrl_find(source->sd->ctrl_handler,624				      V4L2_CID_PIXEL_RATE);625		if (!ctrl) {626			pixelrate = 0;627			break;628		}629 630		/* All source must report the same pixel rate. */631		source_rate = v4l2_ctrl_g_ctrl_int64(ctrl);632		if (!pixelrate) {633			pixelrate = source_rate;634		} else if (pixelrate != source_rate) {635			dev_err(&priv->client->dev,636				"Unable to calculate pixel rate\n");637			return -EINVAL;638		}639	}640 641	if (!pixelrate) {642		dev_err(&priv->client->dev,643			"No pixel rate control available in sources\n");644		return -EINVAL;645	}646 647	priv->pixelrate = pixelrate;648 649	/*650	 * The CSI-2 transmitter pixel rate is the single source rate multiplied651	 * by the number of available sources.652	 */653	return v4l2_ctrl_s_ctrl_int64(priv->pixelrate_ctrl,654				      pixelrate * priv->nsources);655}656 657static int max9286_notify_bound(struct v4l2_async_notifier *notifier,658				struct v4l2_subdev *subdev,659				struct v4l2_async_connection *asd)660{661	struct max9286_priv *priv = sd_to_max9286(notifier->sd);662	struct max9286_source *source = to_max9286_asd(asd)->source;663	unsigned int index = to_index(priv, source);664	unsigned int src_pad;665	int ret;666 667	ret = media_entity_get_fwnode_pad(&subdev->entity,668					  source->fwnode,669					  MEDIA_PAD_FL_SOURCE);670	if (ret < 0) {671		dev_err(&priv->client->dev,672			"Failed to find pad for %s\n", subdev->name);673		return ret;674	}675 676	priv->bound_sources |= BIT(index);677	source->sd = subdev;678	src_pad = ret;679 680	ret = media_create_pad_link(&source->sd->entity, src_pad,681				    &priv->sd.entity, index,682				    MEDIA_LNK_FL_ENABLED |683				    MEDIA_LNK_FL_IMMUTABLE);684	if (ret) {685		dev_err(&priv->client->dev,686			"Unable to link %s:%u -> %s:%u\n",687			source->sd->name, src_pad, priv->sd.name, index);688		return ret;689	}690 691	dev_dbg(&priv->client->dev, "Bound %s pad: %u on index %u\n",692		subdev->name, src_pad, index);693 694	/*695	 * As we register a subdev notifiers we won't get a .complete() callback696	 * here, so we have to use bound_sources to identify when all remote697	 * serializers have probed.698	 */699	if (priv->bound_sources != priv->source_mask)700		return 0;701 702	/*703	 * All enabled sources have probed and enabled their reverse control704	 * channels:705	 *706	 * - Increase the reverse channel amplitude to compensate for the707	 *   remote ends high threshold708	 * - Verify all configuration links are properly detected709	 * - Disable auto-ack as communication on the control channel are now710	 *   stable.711	 */712	max9286_reverse_channel_setup(priv, MAX9286_REV_AMP_HIGH);713	max9286_check_config_link(priv, priv->source_mask);714	max9286_configure_i2c(priv, false);715 716	return max9286_set_pixelrate(priv);717}718 719static void max9286_notify_unbind(struct v4l2_async_notifier *notifier,720				  struct v4l2_subdev *subdev,721				  struct v4l2_async_connection *asd)722{723	struct max9286_priv *priv = sd_to_max9286(notifier->sd);724	struct max9286_source *source = to_max9286_asd(asd)->source;725	unsigned int index = to_index(priv, source);726 727	source->sd = NULL;728	priv->bound_sources &= ~BIT(index);729}730 731static const struct v4l2_async_notifier_operations max9286_notify_ops = {732	.bound = max9286_notify_bound,733	.unbind = max9286_notify_unbind,734};735 736static int max9286_v4l2_notifier_register(struct max9286_priv *priv)737{738	struct device *dev = &priv->client->dev;739	struct max9286_source *source = NULL;740	int ret;741 742	if (!priv->nsources)743		return 0;744 745	v4l2_async_subdev_nf_init(&priv->notifier, &priv->sd);746 747	for_each_source(priv, source) {748		unsigned int i = to_index(priv, source);749		struct max9286_asd *mas;750 751		mas = v4l2_async_nf_add_fwnode(&priv->notifier, source->fwnode,752					       struct max9286_asd);753		if (IS_ERR(mas)) {754			dev_err(dev, "Failed to add subdev for source %u: %ld",755				i, PTR_ERR(mas));756			v4l2_async_nf_cleanup(&priv->notifier);757			return PTR_ERR(mas);758		}759 760		mas->source = source;761	}762 763	priv->notifier.ops = &max9286_notify_ops;764 765	ret = v4l2_async_nf_register(&priv->notifier);766	if (ret) {767		dev_err(dev, "Failed to register subdev_notifier");768		v4l2_async_nf_cleanup(&priv->notifier);769		return ret;770	}771 772	return 0;773}774 775static void max9286_v4l2_notifier_unregister(struct max9286_priv *priv)776{777	if (!priv->nsources)778		return;779 780	v4l2_async_nf_unregister(&priv->notifier);781	v4l2_async_nf_cleanup(&priv->notifier);782}783 784static int max9286_s_stream(struct v4l2_subdev *sd, int enable)785{786	struct max9286_priv *priv = sd_to_max9286(sd);787	struct v4l2_subdev_state *state;788	struct max9286_source *source;789	unsigned int i;790	bool sync = false;791	int ret = 0;792 793	state = v4l2_subdev_lock_and_get_active_state(sd);794 795	if (enable) {796		const struct v4l2_mbus_framefmt *format;797 798		/*799		 * Get the format from the source pad, as all formats must be800		 * identical.801		 */802		format = v4l2_subdev_state_get_format(state, MAX9286_SRC_PAD);803 804		max9286_set_video_format(priv, format);805		max9286_set_fsync_period(priv, state);806 807		/*808		 * The frame sync between cameras is transmitted across the809		 * reverse channel as GPIO. We must open all channels while810		 * streaming to allow this synchronisation signal to be shared.811		 */812		max9286_i2c_mux_open(priv);813 814		/* Start all cameras. */815		for_each_source(priv, source) {816			ret = v4l2_subdev_call(source->sd, video, s_stream, 1);817			if (ret)818				goto unlock;819		}820 821		ret = max9286_check_video_links(priv);822		if (ret)823			goto unlock;824 825		/*826		 * Wait until frame synchronization is locked.827		 *828		 * Manual says frame sync locking should take ~6 VTS.829		 * From practical experience at least 8 are required. Give830		 * 12 complete frames time (~400ms at 30 fps) to achieve frame831		 * locking before returning error.832		 */833		for (i = 0; i < 40; i++) {834			if (max9286_read(priv, 0x31) & MAX9286_FSYNC_LOCKED) {835				sync = true;836				break;837			}838			usleep_range(9000, 11000);839		}840 841		if (!sync) {842			dev_err(&priv->client->dev,843				"Failed to get frame synchronization\n");844			ret = -EXDEV; /* Invalid cross-device link */845			goto unlock;846		}847 848		/*849		 * Configure the CSI-2 output to line interleaved mode (W x (N850		 * x H), as opposed to the (N x W) x H mode that outputs the851		 * images stitched side-by-side) and enable it.852		 */853		max9286_write(priv, 0x15, MAX9286_CSI_IMAGE_TYP | MAX9286_VCTYPE |854			      MAX9286_CSIOUTEN | MAX9286_EN_CCBSYB_CLK_STR |855			      MAX9286_EN_GPI_CCBSYB);856	} else {857		max9286_write(priv, 0x15, MAX9286_VCTYPE |858			      MAX9286_EN_CCBSYB_CLK_STR |859			      MAX9286_EN_GPI_CCBSYB);860 861		/* Stop all cameras. */862		for_each_source(priv, source)863			v4l2_subdev_call(source->sd, video, s_stream, 0);864 865		max9286_i2c_mux_close(priv);866	}867 868unlock:869	v4l2_subdev_unlock_state(state);870 871	return ret;872}873 874static int max9286_get_frame_interval(struct v4l2_subdev *sd,875				      struct v4l2_subdev_state *sd_state,876				      struct v4l2_subdev_frame_interval *interval)877{878	if (interval->pad != MAX9286_SRC_PAD)879		return -EINVAL;880 881	interval->interval = *v4l2_subdev_state_get_interval(sd_state,882							     interval->pad);883 884	return 0;885}886 887static int max9286_set_frame_interval(struct v4l2_subdev *sd,888				      struct v4l2_subdev_state *sd_state,889				      struct v4l2_subdev_frame_interval *interval)890{891	if (interval->pad != MAX9286_SRC_PAD)892		return -EINVAL;893 894	*v4l2_subdev_state_get_interval(sd_state,895					interval->pad) = interval->interval;896 897	return 0;898}899 900static int max9286_enum_mbus_code(struct v4l2_subdev *sd,901				  struct v4l2_subdev_state *sd_state,902				  struct v4l2_subdev_mbus_code_enum *code)903{904	if (code->pad || code->index >= ARRAY_SIZE(max9286_formats))905		return -EINVAL;906 907	code->code = max9286_formats[code->index].code;908 909	return 0;910}911 912static int max9286_set_fmt(struct v4l2_subdev *sd,913			   struct v4l2_subdev_state *state,914			   struct v4l2_subdev_format *format)915{916	struct max9286_priv *priv = sd_to_max9286(sd);917	struct max9286_source *source;918	unsigned int i;919 920	/*921	 * Disable setting format on the source pad: format is propagated922	 * from the sinks.923	 */924	if (format->pad == MAX9286_SRC_PAD)925		return v4l2_subdev_get_fmt(sd, state, format);926 927	/* Validate the format. */928	for (i = 0; i < ARRAY_SIZE(max9286_formats); ++i) {929		if (max9286_formats[i].code == format->format.code)930			break;931	}932 933	if (i == ARRAY_SIZE(max9286_formats))934		format->format.code = max9286_formats[0].code;935 936	/*937	 * Apply the same format on all the other pad as all links must have the938	 * same format.939	 */940	for_each_source(priv, source) {941		unsigned int index = to_index(priv, source);942 943		*v4l2_subdev_state_get_format(state, index) = format->format;944	}945 946	*v4l2_subdev_state_get_format(state, MAX9286_SRC_PAD) = format->format;947 948	return 0;949}950 951static const struct v4l2_subdev_video_ops max9286_video_ops = {952	.s_stream	= max9286_s_stream,953};954 955static const struct v4l2_subdev_pad_ops max9286_pad_ops = {956	.enum_mbus_code = max9286_enum_mbus_code,957	.get_fmt	= v4l2_subdev_get_fmt,958	.set_fmt	= max9286_set_fmt,959	.get_frame_interval = max9286_get_frame_interval,960	.set_frame_interval = max9286_set_frame_interval,961};962 963static const struct v4l2_subdev_ops max9286_subdev_ops = {964	.video		= &max9286_video_ops,965	.pad		= &max9286_pad_ops,966};967 968static const struct v4l2_mbus_framefmt max9286_default_format = {969	.width		= 1280,970	.height		= 800,971	.code		= MEDIA_BUS_FMT_UYVY8_1X16,972	.colorspace	= V4L2_COLORSPACE_SRGB,973	.field		= V4L2_FIELD_NONE,974	.ycbcr_enc	= V4L2_YCBCR_ENC_DEFAULT,975	.quantization	= V4L2_QUANTIZATION_DEFAULT,976	.xfer_func	= V4L2_XFER_FUNC_DEFAULT,977};978 979static int max9286_init_state(struct v4l2_subdev *sd,980			      struct v4l2_subdev_state *state)981{982	struct v4l2_fract *interval;983 984	for (unsigned int i = 0; i < MAX9286_N_PADS; i++)985		*v4l2_subdev_state_get_format(state, i) = max9286_default_format;986 987	/*988	 * Special case: a null interval enables automatic FRAMESYNC mode.989	 *990	 * FRAMESYNC is taken from the slowest link. See register 0x01991	 * configuration.992	 */993	interval = v4l2_subdev_state_get_interval(state, MAX9286_SRC_PAD);994	interval->numerator = 0;995	interval->denominator = 0;996 997	return 0;998}999 1000static const struct v4l2_subdev_internal_ops max9286_subdev_internal_ops = {1001	.init_state = max9286_init_state,1002};1003 1004static const struct media_entity_operations max9286_media_ops = {1005	.link_validate = v4l2_subdev_link_validate1006};1007 1008static int max9286_s_ctrl(struct v4l2_ctrl *ctrl)1009{1010	switch (ctrl->id) {1011	case V4L2_CID_PIXEL_RATE:1012		return 0;1013	default:1014		return -EINVAL;1015	}1016}1017 1018static const struct v4l2_ctrl_ops max9286_ctrl_ops = {1019	.s_ctrl = max9286_s_ctrl,1020};1021 1022static int max9286_v4l2_register(struct max9286_priv *priv)1023{1024	struct device *dev = &priv->client->dev;1025	int ret;1026	int i;1027 1028	/* Register v4l2 async notifiers for connected Camera subdevices */1029	ret = max9286_v4l2_notifier_register(priv);1030	if (ret) {1031		dev_err(dev, "Unable to register V4L2 async notifiers\n");1032		return ret;1033	}1034 1035	/* Configure V4L2 for the MAX9286 itself */1036	v4l2_i2c_subdev_init(&priv->sd, priv->client, &max9286_subdev_ops);1037	priv->sd.internal_ops = &max9286_subdev_internal_ops;1038	priv->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;1039 1040	v4l2_ctrl_handler_init(&priv->ctrls, 1);1041	priv->pixelrate_ctrl = v4l2_ctrl_new_std(&priv->ctrls,1042						 &max9286_ctrl_ops,1043						 V4L2_CID_PIXEL_RATE,1044						 1, INT_MAX, 1, 50000000);1045 1046	priv->sd.ctrl_handler = &priv->ctrls;1047	ret = priv->ctrls.error;1048	if (ret)1049		goto err_async;1050 1051	priv->sd.entity.function = MEDIA_ENT_F_VID_IF_BRIDGE;1052	priv->sd.entity.ops = &max9286_media_ops;1053 1054	priv->pads[MAX9286_SRC_PAD].flags = MEDIA_PAD_FL_SOURCE;1055	for (i = 0; i < MAX9286_SRC_PAD; i++)1056		priv->pads[i].flags = MEDIA_PAD_FL_SINK;1057	ret = media_entity_pads_init(&priv->sd.entity, MAX9286_N_PADS,1058				     priv->pads);1059	if (ret)1060		goto err_async;1061 1062	priv->sd.state_lock = priv->ctrls.lock;1063	ret = v4l2_subdev_init_finalize(&priv->sd);1064	if (ret)1065		goto err_async;1066 1067	ret = v4l2_async_register_subdev(&priv->sd);1068	if (ret < 0) {1069		dev_err(dev, "Unable to register subdevice\n");1070		goto err_subdev;1071	}1072 1073	return 0;1074 1075err_subdev:1076	v4l2_subdev_cleanup(&priv->sd);1077err_async:1078	v4l2_ctrl_handler_free(&priv->ctrls);1079	max9286_v4l2_notifier_unregister(priv);1080 1081	return ret;1082}1083 1084static void max9286_v4l2_unregister(struct max9286_priv *priv)1085{1086	v4l2_subdev_cleanup(&priv->sd);1087	v4l2_ctrl_handler_free(&priv->ctrls);1088	v4l2_async_unregister_subdev(&priv->sd);1089	max9286_v4l2_notifier_unregister(priv);1090}1091 1092/* -----------------------------------------------------------------------------1093 * Probe/Remove1094 */1095 1096static int max9286_setup(struct max9286_priv *priv)1097{1098	/*1099	 * Link ordering values for all enabled links combinations. Orders must1100	 * be assigned sequentially from 0 to the number of enabled links1101	 * without leaving any hole for disabled links. We thus assign orders to1102	 * enabled links first, and use the remaining order values for disabled1103	 * links are all links must have a different order value;1104	 */1105	static const u8 link_order[] = {1106		(3 << 6) | (2 << 4) | (1 << 2) | (0 << 0), /* xxxx */1107		(3 << 6) | (2 << 4) | (1 << 2) | (0 << 0), /* xxx0 */1108		(3 << 6) | (2 << 4) | (0 << 2) | (1 << 0), /* xx0x */1109		(3 << 6) | (2 << 4) | (1 << 2) | (0 << 0), /* xx10 */1110		(3 << 6) | (0 << 4) | (2 << 2) | (1 << 0), /* x0xx */1111		(3 << 6) | (1 << 4) | (2 << 2) | (0 << 0), /* x1x0 */1112		(3 << 6) | (1 << 4) | (0 << 2) | (2 << 0), /* x10x */1113		(3 << 6) | (1 << 4) | (1 << 2) | (0 << 0), /* x210 */1114		(0 << 6) | (3 << 4) | (2 << 2) | (1 << 0), /* 0xxx */1115		(1 << 6) | (3 << 4) | (2 << 2) | (0 << 0), /* 1xx0 */1116		(1 << 6) | (3 << 4) | (0 << 2) | (2 << 0), /* 1x0x */1117		(2 << 6) | (3 << 4) | (1 << 2) | (0 << 0), /* 2x10 */1118		(1 << 6) | (0 << 4) | (3 << 2) | (2 << 0), /* 10xx */1119		(2 << 6) | (1 << 4) | (3 << 2) | (0 << 0), /* 21x0 */1120		(2 << 6) | (1 << 4) | (0 << 2) | (3 << 0), /* 210x */1121		(3 << 6) | (2 << 4) | (1 << 2) | (0 << 0), /* 3210 */1122	};1123	int cfg;1124 1125	/*1126	 * Set the I2C bus speed.1127	 *1128	 * Enable I2C Local Acknowledge during the probe sequences of the camera1129	 * only. This should be disabled after the mux is initialised.1130	 */1131	max9286_configure_i2c(priv, true);1132	max9286_reverse_channel_setup(priv, priv->init_rev_chan_mv);1133 1134	/*1135	 * Enable GMSL links, mask unused ones and autodetect link1136	 * used as CSI clock source.1137	 */1138	max9286_write(priv, 0x00, MAX9286_MSTLINKSEL_AUTO | priv->route_mask);1139	max9286_write(priv, 0x0b, link_order[priv->route_mask]);1140	max9286_write(priv, 0x69, (0xf & ~priv->route_mask));1141 1142	max9286_set_video_format(priv, &max9286_default_format);1143 1144	cfg = max9286_read(priv, 0x1c);1145	if (cfg < 0)1146		return cfg;1147 1148	dev_dbg(&priv->client->dev, "power-up config: %s immunity, %u-bit bus\n",1149		cfg & MAX9286_HIGHIMM(0) ? "high" : "legacy",1150		cfg & MAX9286_BWS ? 32 : cfg & MAX9286_HIBW ? 27 : 24);1151 1152	if (priv->bus_width) {1153		cfg &= ~(MAX9286_HIBW | MAX9286_BWS);1154 1155		if (priv->bus_width == 27)1156			cfg |= MAX9286_HIBW;1157		else if (priv->bus_width == 32)1158			cfg |= MAX9286_BWS;1159 1160		max9286_write(priv, 0x1c, cfg);1161	}1162 1163	/*1164	 * The overlap window seems to provide additional validation by tracking1165	 * the delay between vsync and frame sync, generating an error if the1166	 * delay is bigger than the programmed window, though it's not yet clear1167	 * what value should be set.1168	 *1169	 * As it's an optional value and can be disabled, we do so by setting1170	 * a 0 overlap value.1171	 */1172	max9286_write(priv, 0x63, 0);1173	max9286_write(priv, 0x64, 0);1174 1175	/*1176	 * Wait for 2ms to allow the link to resynchronize after the1177	 * configuration change.1178	 */1179	usleep_range(2000, 5000);1180 1181	return 0;1182}1183 1184static int max9286_gpio_set(struct max9286_priv *priv, unsigned int offset,1185			    int value)1186{1187	if (value)1188		priv->gpio_state |= BIT(offset);1189	else1190		priv->gpio_state &= ~BIT(offset);1191 1192	return max9286_write(priv, 0x0f,1193			     MAX9286_0X0F_RESERVED | priv->gpio_state);1194}1195 1196static void max9286_gpiochip_set(struct gpio_chip *chip,1197				 unsigned int offset, int value)1198{1199	struct max9286_priv *priv = gpiochip_get_data(chip);1200 1201	max9286_gpio_set(priv, offset, value);1202}1203 1204static int max9286_gpiochip_get(struct gpio_chip *chip, unsigned int offset)1205{1206	struct max9286_priv *priv = gpiochip_get_data(chip);1207 1208	return priv->gpio_state & BIT(offset);1209}1210 1211static int max9286_register_gpio(struct max9286_priv *priv)1212{1213	struct device *dev = &priv->client->dev;1214	struct gpio_chip *gpio = &priv->gpio;1215	int ret;1216 1217	/* Configure the GPIO */1218	gpio->label = dev_name(dev);1219	gpio->parent = dev;1220	gpio->owner = THIS_MODULE;1221	gpio->ngpio = 2;1222	gpio->base = -1;1223	gpio->set = max9286_gpiochip_set;1224	gpio->get = max9286_gpiochip_get;1225	gpio->can_sleep = true;1226 1227	ret = devm_gpiochip_add_data(dev, gpio, priv);1228	if (ret)1229		dev_err(dev, "Unable to create gpio_chip\n");1230 1231	return ret;1232}1233 1234static int max9286_parse_gpios(struct max9286_priv *priv)1235{1236	struct device *dev = &priv->client->dev;1237	int ret;1238 1239	/*1240	 * Parse the "gpio-poc" vendor property. If the property is not1241	 * specified the camera power is controlled by a regulator.1242	 */1243	ret = of_property_read_u32_array(dev->of_node, "maxim,gpio-poc",1244					 priv->gpio_poc, 2);1245	if (ret == -EINVAL) {1246		/*1247		 * If gpio lines are not used for the camera power, register1248		 * a gpio controller for consumers.1249		 */1250		return max9286_register_gpio(priv);1251	}1252 1253	/* If the property is specified make sure it is well formed. */1254	if (ret || priv->gpio_poc[0] > 1 ||1255	    (priv->gpio_poc[1] != GPIO_ACTIVE_HIGH &&1256	     priv->gpio_poc[1] != GPIO_ACTIVE_LOW)) {1257		dev_err(dev, "Invalid 'gpio-poc' property\n");1258		return -EINVAL;1259	}1260 1261	priv->use_gpio_poc = true;1262	return 0;1263}1264 1265static int max9286_poc_power_on(struct max9286_priv *priv)1266{1267	struct max9286_source *source;1268	unsigned int enabled = 0;1269	int ret;1270 1271	/* Enable the global regulator if available. */1272	if (priv->regulator)1273		return regulator_enable(priv->regulator);1274 1275	if (priv->use_gpio_poc)1276		return max9286_gpio_set(priv, priv->gpio_poc[0],1277					!priv->gpio_poc[1]);1278 1279	/* Otherwise use the per-port regulators. */1280	for_each_source(priv, source) {1281		ret = regulator_enable(source->regulator);1282		if (ret < 0)1283			goto error;1284 1285		enabled |= BIT(to_index(priv, source));1286	}1287 1288	return 0;1289 1290error:1291	for_each_source(priv, source) {1292		if (enabled & BIT(to_index(priv, source)))1293			regulator_disable(source->regulator);1294	}1295 1296	return ret;1297}1298 1299static int max9286_poc_power_off(struct max9286_priv *priv)1300{1301	struct max9286_source *source;1302	int ret = 0;1303 1304	if (priv->regulator)1305		return regulator_disable(priv->regulator);1306 1307	if (priv->use_gpio_poc)1308		return max9286_gpio_set(priv, priv->gpio_poc[0],1309					priv->gpio_poc[1]);1310 1311	for_each_source(priv, source) {1312		int err;1313 1314		err = regulator_disable(source->regulator);1315		if (!ret)1316			ret = err;1317	}1318 1319	return ret;1320}1321 1322static int max9286_poc_enable(struct max9286_priv *priv, bool enable)1323{1324	int ret;1325 1326	if (enable)1327		ret = max9286_poc_power_on(priv);1328	else1329		ret = max9286_poc_power_off(priv);1330 1331	if (ret < 0)1332		dev_err(&priv->client->dev, "Unable to turn power %s\n",1333			enable ? "on" : "off");1334 1335	return ret;1336}1337 1338static int max9286_init(struct max9286_priv *priv)1339{1340	struct i2c_client *client = priv->client;1341	int ret;1342 1343	ret = max9286_poc_enable(priv, true);1344	if (ret)1345		return ret;1346 1347	ret = max9286_setup(priv);1348	if (ret) {1349		dev_err(&client->dev, "Unable to setup max9286\n");1350		goto err_poc_disable;1351	}1352 1353	/*1354	 * Register all V4L2 interactions for the MAX9286 and notifiers for1355	 * any subdevices connected.1356	 */1357	ret = max9286_v4l2_register(priv);1358	if (ret) {1359		dev_err(&client->dev, "Failed to register with V4L2\n");1360		goto err_poc_disable;1361	}1362 1363	ret = max9286_i2c_mux_init(priv);1364	if (ret) {1365		dev_err(&client->dev, "Unable to initialize I2C multiplexer\n");1366		goto err_v4l2_register;1367	}1368 1369	/* Leave the mux channels disabled until they are selected. */1370	max9286_i2c_mux_close(priv);1371 1372	return 0;1373 1374err_v4l2_register:1375	max9286_v4l2_unregister(priv);1376err_poc_disable:1377	max9286_poc_enable(priv, false);1378 1379	return ret;1380}1381 1382static void max9286_cleanup_dt(struct max9286_priv *priv)1383{1384	struct max9286_source *source;1385 1386	for_each_source(priv, source) {1387		fwnode_handle_put(source->fwnode);1388		source->fwnode = NULL;1389	}1390}1391 1392static int max9286_parse_dt(struct max9286_priv *priv)1393{1394	struct device *dev = &priv->client->dev;1395	struct device_node *i2c_mux;1396	struct device_node *node = NULL;1397	unsigned int i2c_mux_mask = 0;1398	u32 reverse_channel_microvolt;1399	u32 i2c_clk_freq = 105000;1400	unsigned int i;1401 1402	/* Balance the of_node_put() performed by of_find_node_by_name(). */1403	of_node_get(dev->of_node);1404	i2c_mux = of_find_node_by_name(dev->of_node, "i2c-mux");1405	if (!i2c_mux) {1406		dev_err(dev, "Failed to find i2c-mux node\n");1407		return -EINVAL;1408	}1409 1410	/* Identify which i2c-mux channels are enabled */1411	for_each_child_of_node(i2c_mux, node) {1412		u32 id = 0;1413 1414		of_property_read_u32(node, "reg", &id);1415		if (id >= MAX9286_NUM_GMSL)1416			continue;1417 1418		if (!of_device_is_available(node)) {1419			dev_dbg(dev, "Skipping disabled I2C bus port %u\n", id);1420			continue;1421		}1422 1423		i2c_mux_mask |= BIT(id);1424	}1425	of_node_put(i2c_mux);1426 1427	/* Parse the endpoints */1428	for_each_endpoint_of_node(dev->of_node, node) {1429		struct max9286_source *source;1430		struct of_endpoint ep;1431 1432		of_graph_parse_endpoint(node, &ep);1433		dev_dbg(dev, "Endpoint %pOF on port %d",1434			ep.local_node, ep.port);1435 1436		if (ep.port > MAX9286_NUM_GMSL) {1437			dev_err(dev, "Invalid endpoint %s on port %d",1438				of_node_full_name(ep.local_node), ep.port);1439			continue;1440		}1441 1442		/* For the source endpoint just parse the bus configuration. */1443		if (ep.port == MAX9286_SRC_PAD) {1444			struct v4l2_fwnode_endpoint vep = {1445				.bus_type = V4L2_MBUS_CSI2_DPHY1446			};1447			int ret;1448 1449			ret = v4l2_fwnode_endpoint_parse(1450					of_fwnode_handle(node), &vep);1451			if (ret) {1452				of_node_put(node);1453				return ret;1454			}1455 1456			priv->csi2_data_lanes =1457				vep.bus.mipi_csi2.num_data_lanes;1458 1459			continue;1460		}1461 1462		/* Skip if the corresponding GMSL link is unavailable. */1463		if (!(i2c_mux_mask & BIT(ep.port)))1464			continue;1465 1466		if (priv->sources[ep.port].fwnode) {1467			dev_err(dev,1468				"Multiple port endpoints are not supported: %d",1469				ep.port);1470 1471			continue;1472		}1473 1474		source = &priv->sources[ep.port];1475		source->fwnode = fwnode_graph_get_remote_endpoint(1476						of_fwnode_handle(node));1477		if (!source->fwnode) {1478			dev_err(dev,1479				"Endpoint %pOF has no remote endpoint connection\n",1480				ep.local_node);1481 1482			continue;1483		}1484 1485		priv->source_mask |= BIT(ep.port);1486		priv->nsources++;1487	}1488 1489	of_property_read_u32(dev->of_node, "maxim,bus-width", &priv->bus_width);1490	switch (priv->bus_width) {1491	case 0:1492		/*1493		 * The property isn't specified in the device tree, the driver1494		 * will keep the default value selected by the BWS pin.1495		 */1496	case 24:1497	case 27:1498	case 32:1499		break;1500	default:1501		dev_err(dev, "Invalid %s value %u\n", "maxim,bus-width",1502			priv->bus_width);1503		return -EINVAL;1504	}1505 1506	of_property_read_u32(dev->of_node, "maxim,i2c-remote-bus-hz",1507			     &i2c_clk_freq);1508	for (i = 0; i < ARRAY_SIZE(max9286_i2c_speeds); ++i) {1509		const struct max9286_i2c_speed *speed = &max9286_i2c_speeds[i];1510 1511		if (speed->rate == i2c_clk_freq) {1512			priv->i2c_mstbt = speed->mstbt;1513			break;1514		}1515	}1516 1517	if (i == ARRAY_SIZE(max9286_i2c_speeds)) {1518		dev_err(dev, "Invalid %s value %u\n", "maxim,i2c-remote-bus-hz",1519			i2c_clk_freq);1520		return -EINVAL;1521	}1522 1523	/*1524	 * Parse the initial value of the reverse channel amplitude from1525	 * the firmware interface and convert it to millivolts.1526	 *1527	 * Default it to 170mV for backward compatibility with DTBs that do not1528	 * provide the property.1529	 */1530	if (of_property_read_u32(dev->of_node,1531				 "maxim,reverse-channel-microvolt",1532				 &reverse_channel_microvolt))1533		priv->init_rev_chan_mv = 170;1534	else1535		priv->init_rev_chan_mv = reverse_channel_microvolt / 1000U;1536 1537	priv->route_mask = priv->source_mask;1538 1539	return 0;1540}1541 1542static int max9286_get_poc_supplies(struct max9286_priv *priv)1543{1544	struct device *dev = &priv->client->dev;1545	struct max9286_source *source;1546	int ret;1547 1548	/* Start by getting the global regulator. */1549	priv->regulator = devm_regulator_get_optional(dev, "poc");1550	if (!IS_ERR(priv->regulator))1551		return 0;1552 1553	if (PTR_ERR(priv->regulator) != -ENODEV)1554		return dev_err_probe(dev, PTR_ERR(priv->regulator),1555				     "Unable to get PoC regulator\n");1556 1557	/* If there's no global regulator, get per-port regulators. */1558	dev_dbg(dev,1559		"No global PoC regulator, looking for per-port regulators\n");1560	priv->regulator = NULL;1561 1562	for_each_source(priv, source) {1563		unsigned int index = to_index(priv, source);1564		char name[10];1565 1566		snprintf(name, sizeof(name), "port%u-poc", index);1567		source->regulator = devm_regulator_get(dev, name);1568		if (IS_ERR(source->regulator)) {1569			ret = PTR_ERR(source->regulator);1570			dev_err_probe(dev, ret,1571				      "Unable to get port %u PoC regulator\n",1572				      index);1573			return ret;1574		}1575	}1576 1577	return 0;1578}1579 1580static int max9286_probe(struct i2c_client *client)1581{1582	struct max9286_priv *priv;1583	int ret;1584 1585	priv = devm_kzalloc(&client->dev, sizeof(*priv), GFP_KERNEL);1586	if (!priv)1587		return -ENOMEM;1588 1589	priv->client = client;1590 1591	/* GPIO values default to high */1592	priv->gpio_state = BIT(0) | BIT(1);1593 1594	ret = max9286_parse_dt(priv);1595	if (ret)1596		goto err_cleanup_dt;1597 1598	priv->gpiod_pwdn = devm_gpiod_get_optional(&client->dev, "enable",1599						   GPIOD_OUT_HIGH);1600	if (IS_ERR(priv->gpiod_pwdn)) {1601		ret = PTR_ERR(priv->gpiod_pwdn);1602		goto err_cleanup_dt;1603	}1604 1605	gpiod_set_consumer_name(priv->gpiod_pwdn, "max9286-pwdn");1606	gpiod_set_value_cansleep(priv->gpiod_pwdn, 1);1607 1608	/* Wait at least 4ms before the I2C lines latch to the address */1609	if (priv->gpiod_pwdn)1610		usleep_range(4000, 5000);1611 1612	/*1613	 * The MAX9286 starts by default with all ports enabled, we disable all1614	 * ports early to ensure that all channels are disabled if we error out1615	 * and keep the bus consistent.1616	 */1617	max9286_i2c_mux_close(priv);1618 1619	/*1620	 * The MAX9286 initialises with auto-acknowledge enabled by default.1621	 * This can be invasive to other transactions on the same bus, so1622	 * disable it early. It will be enabled only as and when needed.1623	 */1624	max9286_configure_i2c(priv, false);1625 1626	ret = max9286_parse_gpios(priv);1627	if (ret)1628		goto err_powerdown;1629 1630	if (!priv->use_gpio_poc) {1631		ret = max9286_get_poc_supplies(priv);1632		if (ret)1633			goto err_cleanup_dt;1634	}1635 1636	ret = max9286_init(priv);1637	if (ret < 0)1638		goto err_cleanup_dt;1639 1640	return 0;1641 1642err_powerdown:1643	gpiod_set_value_cansleep(priv->gpiod_pwdn, 0);1644err_cleanup_dt:1645	max9286_cleanup_dt(priv);1646 1647	return ret;1648}1649 1650static void max9286_remove(struct i2c_client *client)1651{1652	struct max9286_priv *priv = sd_to_max9286(i2c_get_clientdata(client));1653 1654	i2c_mux_del_adapters(priv->mux);1655 1656	max9286_v4l2_unregister(priv);1657 1658	max9286_poc_enable(priv, false);1659 1660	gpiod_set_value_cansleep(priv->gpiod_pwdn, 0);1661 1662	max9286_cleanup_dt(priv);1663}1664 1665static const struct of_device_id max9286_dt_ids[] = {1666	{ .compatible = "maxim,max9286" },1667	{},1668};1669MODULE_DEVICE_TABLE(of, max9286_dt_ids);1670 1671static struct i2c_driver max9286_i2c_driver = {1672	.driver	= {1673		.name		= "max9286",1674		.of_match_table	= max9286_dt_ids,1675	},1676	.probe		= max9286_probe,1677	.remove		= max9286_remove,1678};1679 1680module_i2c_driver(max9286_i2c_driver);1681 1682MODULE_DESCRIPTION("Maxim MAX9286 GMSL Deserializer Driver");1683MODULE_AUTHOR("Jacopo Mondi, Kieran Bingham, Laurent Pinchart, Niklas Söderlund, Vladimir Barinov");1684MODULE_LICENSE("GPL");1685