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1// SPDX-License-Identifier: GPL-2.0+2 3/*4 * Multifunction core driver for Zodiac Inflight Innovations RAVE5 * Supervisory Processor(SP) MCU that is connected via dedicated UART6 * port7 *8 * Copyright (C) 2017 Zodiac Inflight Innovations9 */10 11#include <linux/atomic.h>12#include <linux/crc-itu-t.h>13#include <linux/delay.h>14#include <linux/export.h>15#include <linux/init.h>16#include <linux/slab.h>17#include <linux/kernel.h>18#include <linux/mfd/rave-sp.h>19#include <linux/module.h>20#include <linux/of.h>21#include <linux/of_platform.h>22#include <linux/sched.h>23#include <linux/serdev.h>24#include <linux/unaligned.h>25 26/*27 * UART protocol using following entities:28 *  - message to MCU => ACK response29 *  - event from MCU => event ACK30 *31 * Frame structure:32 * <STX> <DATA> <CHECKSUM> <ETX>33 * Where:34 * - STX - is start of transmission character35 * - ETX - end of transmission36 * - DATA - payload37 * - CHECKSUM - checksum calculated on <DATA>38 *39 * If <DATA> or <CHECKSUM> contain one of control characters, then it is40 * escaped using <DLE> control code. Added <DLE> does not participate in41 * checksum calculation.42 */43#define RAVE_SP_STX			0x0244#define RAVE_SP_ETX			0x0345#define RAVE_SP_DLE			0x1046 47#define RAVE_SP_MAX_DATA_SIZE		6448#define RAVE_SP_CHECKSUM_8B2C		149#define RAVE_SP_CHECKSUM_CCITT		250#define RAVE_SP_CHECKSUM_SIZE		RAVE_SP_CHECKSUM_CCITT51/*52 * We don't store STX, ETX and unescaped bytes, so Rx is only53 * DATA + CSUM54 */55#define RAVE_SP_RX_BUFFER_SIZE				\56	(RAVE_SP_MAX_DATA_SIZE + RAVE_SP_CHECKSUM_SIZE)57 58#define RAVE_SP_STX_ETX_SIZE		259/*60 * For Tx we have to have space for everything, STX, EXT and61 * potentially stuffed DATA + CSUM data + csum62 */63#define RAVE_SP_TX_BUFFER_SIZE				\64	(RAVE_SP_STX_ETX_SIZE + 2 * RAVE_SP_RX_BUFFER_SIZE)65 66/**67 * enum rave_sp_deframer_state - Possible state for de-framer68 *69 * @RAVE_SP_EXPECT_SOF:		 Scanning input for start-of-frame marker70 * @RAVE_SP_EXPECT_DATA:	 Got start of frame marker, collecting frame71 * @RAVE_SP_EXPECT_ESCAPED_DATA: Got escape character, collecting escaped byte72 */73enum rave_sp_deframer_state {74	RAVE_SP_EXPECT_SOF,75	RAVE_SP_EXPECT_DATA,76	RAVE_SP_EXPECT_ESCAPED_DATA,77};78 79/**80 * struct rave_sp_deframer - Device protocol deframer81 *82 * @state:  Current state of the deframer83 * @data:   Buffer used to collect deframed data84 * @length: Number of bytes de-framed so far85 */86struct rave_sp_deframer {87	enum rave_sp_deframer_state state;88	unsigned char data[RAVE_SP_RX_BUFFER_SIZE];89	size_t length;90};91 92/**93 * struct rave_sp_reply - Reply as per RAVE device protocol94 *95 * @length:	Expected reply length96 * @data:	Buffer to store reply payload in97 * @code:	Expected reply code98 * @ackid:	Expected reply ACK ID99 * @received:   Successful reply reception completion100 */101struct rave_sp_reply {102	size_t length;103	void  *data;104	u8     code;105	u8     ackid;106	struct completion received;107};108 109/**110 * struct rave_sp_checksum - Variant specific checksum implementation details111 *112 * @length:	Calculated checksum length113 * @subroutine:	Utilized checksum algorithm implementation114 */115struct rave_sp_checksum {116	size_t length;117	void (*subroutine)(const u8 *, size_t, u8 *);118};119 120struct rave_sp_version {121	u8     hardware;122	__le16 major;123	u8     minor;124	u8     letter[2];125} __packed;126 127struct rave_sp_status {128	struct rave_sp_version bootloader_version;129	struct rave_sp_version firmware_version;130	u16 rdu_eeprom_flag;131	u16 dds_eeprom_flag;132	u8  pic_flag;133	u8  orientation;134	u32 etc;135	s16 temp[2];136	u8  backlight_current[3];137	u8  dip_switch;138	u8  host_interrupt;139	u16 voltage_28;140	u8  i2c_device_status;141	u8  power_status;142	u8  general_status;143	u8  deprecated1;144	u8  power_led_status;145	u8  deprecated2;146	u8  periph_power_shutoff;147} __packed;148 149/**150 * struct rave_sp_variant_cmds - Variant specific command routines151 *152 * @translate:	Generic to variant specific command mapping routine153 * @get_status: Variant specific implementation of CMD_GET_STATUS154 */155struct rave_sp_variant_cmds {156	int (*translate)(enum rave_sp_command);157	int (*get_status)(struct rave_sp *sp, struct rave_sp_status *);158};159 160/**161 * struct rave_sp_variant - RAVE supervisory processor core variant162 *163 * @checksum:	Variant specific checksum implementation164 * @cmd:	Variant specific command pointer table165 *166 */167struct rave_sp_variant {168	const struct rave_sp_checksum *checksum;169	struct rave_sp_variant_cmds cmd;170};171 172/**173 * struct rave_sp - RAVE supervisory processor core174 *175 * @serdev:			Pointer to underlying serdev176 * @deframer:			Stored state of the protocol deframer177 * @ackid:			ACK ID used in last reply sent to the device178 * @bus_lock:			Lock to serialize access to the device179 * @reply_lock:			Lock protecting @reply180 * @reply:			Pointer to memory to store reply payload181 *182 * @variant:			Device variant specific information183 * @event_notifier_list:	Input event notification chain184 *185 * @part_number_firmware:	Firmware version186 * @part_number_bootloader:	Bootloader version187 */188struct rave_sp {189	struct serdev_device *serdev;190	struct rave_sp_deframer deframer;191	atomic_t ackid;192	struct mutex bus_lock;193	struct mutex reply_lock;194	struct rave_sp_reply *reply;195 196	const struct rave_sp_variant *variant;197	struct blocking_notifier_head event_notifier_list;198 199	const char *part_number_firmware;200	const char *part_number_bootloader;201};202 203static bool rave_sp_id_is_event(u8 code)204{205	return (code & 0xF0) == RAVE_SP_EVNT_BASE;206}207 208static void rave_sp_unregister_event_notifier(struct device *dev, void *res)209{210	struct rave_sp *sp = dev_get_drvdata(dev->parent);211	struct notifier_block *nb = *(struct notifier_block **)res;212	struct blocking_notifier_head *bnh = &sp->event_notifier_list;213 214	WARN_ON(blocking_notifier_chain_unregister(bnh, nb));215}216 217int devm_rave_sp_register_event_notifier(struct device *dev,218					 struct notifier_block *nb)219{220	struct rave_sp *sp = dev_get_drvdata(dev->parent);221	struct notifier_block **rcnb;222	int ret;223 224	rcnb = devres_alloc(rave_sp_unregister_event_notifier,225			    sizeof(*rcnb), GFP_KERNEL);226	if (!rcnb)227		return -ENOMEM;228 229	ret = blocking_notifier_chain_register(&sp->event_notifier_list, nb);230	if (!ret) {231		*rcnb = nb;232		devres_add(dev, rcnb);233	} else {234		devres_free(rcnb);235	}236 237	return ret;238}239EXPORT_SYMBOL_GPL(devm_rave_sp_register_event_notifier);240 241static void csum_8b2c(const u8 *buf, size_t size, u8 *crc)242{243	*crc = *buf++;244	size--;245 246	while (size--)247		*crc += *buf++;248 249	*crc = 1 + ~(*crc);250}251 252static void csum_ccitt(const u8 *buf, size_t size, u8 *crc)253{254	const u16 calculated = crc_itu_t(0xffff, buf, size);255 256	/*257	 * While the rest of the wire protocol is little-endian,258	 * CCITT-16 CRC in RDU2 device is sent out in big-endian order.259	 */260	put_unaligned_be16(calculated, crc);261}262 263static void *stuff(unsigned char *dest, const unsigned char *src, size_t n)264{265	while (n--) {266		const unsigned char byte = *src++;267 268		switch (byte) {269		case RAVE_SP_STX:270		case RAVE_SP_ETX:271		case RAVE_SP_DLE:272			*dest++ = RAVE_SP_DLE;273			fallthrough;274		default:275			*dest++ = byte;276		}277	}278 279	return dest;280}281 282static int rave_sp_write(struct rave_sp *sp, const u8 *data, u8 data_size)283{284	const size_t checksum_length = sp->variant->checksum->length;285	unsigned char frame[RAVE_SP_TX_BUFFER_SIZE];286	unsigned char crc[RAVE_SP_CHECKSUM_SIZE];287	unsigned char *dest = frame;288	size_t length;289 290	if (WARN_ON(checksum_length > sizeof(crc)))291		return -ENOMEM;292 293	if (WARN_ON(data_size > sizeof(frame)))294		return -ENOMEM;295 296	sp->variant->checksum->subroutine(data, data_size, crc);297 298	*dest++ = RAVE_SP_STX;299	dest = stuff(dest, data, data_size);300	dest = stuff(dest, crc, checksum_length);301	*dest++ = RAVE_SP_ETX;302 303	length = dest - frame;304 305	print_hex_dump_debug("rave-sp tx: ", DUMP_PREFIX_NONE,306			     16, 1, frame, length, false);307 308	return serdev_device_write(sp->serdev, frame, length, HZ);309}310 311static u8 rave_sp_reply_code(u8 command)312{313	/*314	 * There isn't a single rule that describes command code ->315	 * ACK code transformation, but, going through various316	 * versions of ICDs, there appear to be three distinct groups317	 * that can be described by simple transformation.318	 */319	switch (command) {320	case 0xA0 ... 0xBE:321		/*322		 * Commands implemented by firmware found in RDU1 and323		 * older devices all seem to obey the following rule324		 */325		return command + 0x20;326	case 0xE0 ... 0xEF:327		/*328		 * Events emitted by all versions of the firmare use329		 * least significant bit to get an ACK code330		 */331		return command | 0x01;332	default:333		/*334		 * Commands implemented by firmware found in RDU2 are335		 * similar to "old" commands, but they use slightly336		 * different offset337		 */338		return command + 0x40;339	}340}341 342int rave_sp_exec(struct rave_sp *sp,343		 void *__data,  size_t data_size,344		 void *reply_data, size_t reply_data_size)345{346	struct rave_sp_reply reply = {347		.data     = reply_data,348		.length   = reply_data_size,349		.received = COMPLETION_INITIALIZER_ONSTACK(reply.received),350	};351	unsigned char *data = __data;352	int command, ret = 0;353	u8 ackid;354 355	command = sp->variant->cmd.translate(data[0]);356	if (command < 0)357		return command;358 359	ackid       = atomic_inc_return(&sp->ackid);360	reply.ackid = ackid;361	reply.code  = rave_sp_reply_code((u8)command);362 363	mutex_lock(&sp->bus_lock);364 365	mutex_lock(&sp->reply_lock);366	sp->reply = &reply;367	mutex_unlock(&sp->reply_lock);368 369	data[0] = command;370	data[1] = ackid;371 372	rave_sp_write(sp, data, data_size);373 374	if (!wait_for_completion_timeout(&reply.received, HZ)) {375		dev_err(&sp->serdev->dev, "Command timeout\n");376		ret = -ETIMEDOUT;377 378		mutex_lock(&sp->reply_lock);379		sp->reply = NULL;380		mutex_unlock(&sp->reply_lock);381	}382 383	mutex_unlock(&sp->bus_lock);384	return ret;385}386EXPORT_SYMBOL_GPL(rave_sp_exec);387 388static void rave_sp_receive_event(struct rave_sp *sp,389				  const unsigned char *data, size_t length)390{391	u8 cmd[] = {392		[0] = rave_sp_reply_code(data[0]),393		[1] = data[1],394	};395 396	rave_sp_write(sp, cmd, sizeof(cmd));397 398	blocking_notifier_call_chain(&sp->event_notifier_list,399				     rave_sp_action_pack(data[0], data[2]),400				     NULL);401}402 403static void rave_sp_receive_reply(struct rave_sp *sp,404				  const unsigned char *data, size_t length)405{406	struct device *dev = &sp->serdev->dev;407	struct rave_sp_reply *reply;408	const  size_t payload_length = length - 2;409 410	mutex_lock(&sp->reply_lock);411	reply = sp->reply;412 413	if (reply) {414		if (reply->code == data[0] && reply->ackid == data[1] &&415		    payload_length >= reply->length) {416			/*417			 * We are relying on memcpy(dst, src, 0) to be a no-op418			 * when handling commands that have a no-payload reply419			 */420			memcpy(reply->data, &data[2], reply->length);421			complete(&reply->received);422			sp->reply = NULL;423		} else {424			dev_err(dev, "Ignoring incorrect reply\n");425			dev_dbg(dev, "Code:   expected = 0x%08x received = 0x%08x\n",426				reply->code, data[0]);427			dev_dbg(dev, "ACK ID: expected = 0x%08x received = 0x%08x\n",428				reply->ackid, data[1]);429			dev_dbg(dev, "Length: expected = %zu received = %zu\n",430				reply->length, payload_length);431		}432	}433 434	mutex_unlock(&sp->reply_lock);435}436 437static void rave_sp_receive_frame(struct rave_sp *sp,438				  const unsigned char *data,439				  size_t length)440{441	const size_t checksum_length = sp->variant->checksum->length;442	const size_t payload_length  = length - checksum_length;443	const u8 *crc_reported       = &data[payload_length];444	struct device *dev           = &sp->serdev->dev;445	u8 crc_calculated[RAVE_SP_CHECKSUM_SIZE];446 447	if (unlikely(checksum_length > sizeof(crc_calculated))) {448		dev_warn(dev, "Checksum too long, dropping\n");449		return;450	}451 452	print_hex_dump_debug("rave-sp rx: ", DUMP_PREFIX_NONE,453			     16, 1, data, length, false);454 455	if (unlikely(length <= checksum_length)) {456		dev_warn(dev, "Dropping short frame\n");457		return;458	}459 460	sp->variant->checksum->subroutine(data, payload_length,461					  crc_calculated);462 463	if (memcmp(crc_calculated, crc_reported, checksum_length)) {464		dev_warn(dev, "Dropping bad frame\n");465		return;466	}467 468	if (rave_sp_id_is_event(data[0]))469		rave_sp_receive_event(sp, data, length);470	else471		rave_sp_receive_reply(sp, data, length);472}473 474static size_t rave_sp_receive_buf(struct serdev_device *serdev,475				  const u8 *buf, size_t size)476{477	struct device *dev = &serdev->dev;478	struct rave_sp *sp = dev_get_drvdata(dev);479	struct rave_sp_deframer *deframer = &sp->deframer;480	const u8 *src = buf;481	const u8 *end = buf + size;482 483	while (src < end) {484		const u8 byte = *src++;485 486		switch (deframer->state) {487		case RAVE_SP_EXPECT_SOF:488			if (byte == RAVE_SP_STX)489				deframer->state = RAVE_SP_EXPECT_DATA;490			break;491 492		case RAVE_SP_EXPECT_DATA:493			/*494			 * Treat special byte values first495			 */496			switch (byte) {497			case RAVE_SP_ETX:498				rave_sp_receive_frame(sp,499						      deframer->data,500						      deframer->length);501				/*502				 * Once we extracted a complete frame503				 * out of a stream, we call it done504				 * and proceed to bailing out while505				 * resetting the framer to initial506				 * state, regardless if we've consumed507				 * all of the stream or not.508				 */509				goto reset_framer;510			case RAVE_SP_STX:511				dev_warn(dev, "Bad frame: STX before ETX\n");512				/*513				 * If we encounter second "start of514				 * the frame" marker before seeing515				 * corresponding "end of frame", we516				 * reset the framer and ignore both:517				 * frame started by first SOF and518				 * frame started by current SOF.519				 *520				 * NOTE: The above means that only the521				 * frame started by third SOF, sent522				 * after this one will have a chance523				 * to get throught.524				 */525				goto reset_framer;526			case RAVE_SP_DLE:527				deframer->state = RAVE_SP_EXPECT_ESCAPED_DATA;528				/*529				 * If we encounter escape sequence we530				 * need to skip it and collect the531				 * byte that follows. We do it by532				 * forcing the next iteration of the533				 * encompassing while loop.534				 */535				continue;536			}537			/*538			 * For the rest of the bytes, that are not539			 * speical snoflakes, we do the same thing540			 * that we do to escaped data - collect it in541			 * deframer buffer542			 */543 544			fallthrough;545 546		case RAVE_SP_EXPECT_ESCAPED_DATA:547			if (deframer->length == sizeof(deframer->data)) {548				dev_warn(dev, "Bad frame: Too long\n");549				/*550				 * If the amount of data we've551				 * accumulated for current frame so552				 * far starts to exceed the capacity553				 * of deframer's buffer, there's554				 * nothing else we can do but to555				 * discard that data and start556				 * assemblying a new frame again557				 */558				goto reset_framer;559			}560 561			deframer->data[deframer->length++] = byte;562 563			/*564			 * We've extracted out special byte, now we565			 * can go back to regular data collecting566			 */567			deframer->state = RAVE_SP_EXPECT_DATA;568			break;569		}570	}571 572	/*573	 * The only way to get out of the above loop and end up here574	 * is throught consuming all of the supplied data, so here we575	 * report that we processed it all.576	 */577	return size;578 579reset_framer:580	/*581	 * NOTE: A number of codepaths that will drop us here will do582	 * so before consuming all 'size' bytes of the data passed by583	 * serdev layer. We rely on the fact that serdev layer will584	 * re-execute this handler with the remainder of the Rx bytes585	 * once we report actual number of bytes that we processed.586	 */587	deframer->state  = RAVE_SP_EXPECT_SOF;588	deframer->length = 0;589 590	return src - buf;591}592 593static int rave_sp_rdu1_cmd_translate(enum rave_sp_command command)594{595	if (command >= RAVE_SP_CMD_STATUS &&596	    command <= RAVE_SP_CMD_CONTROL_EVENTS)597		return command;598 599	return -EINVAL;600}601 602static int rave_sp_rdu2_cmd_translate(enum rave_sp_command command)603{604	if (command >= RAVE_SP_CMD_GET_FIRMWARE_VERSION &&605	    command <= RAVE_SP_CMD_GET_GPIO_STATE)606		return command;607 608	if (command == RAVE_SP_CMD_REQ_COPPER_REV) {609		/*610		 * As per RDU2 ICD 3.4.47 CMD_GET_COPPER_REV code is611		 * different from that for RDU1 and it is set to 0x28.612		 */613		return 0x28;614	}615 616	return rave_sp_rdu1_cmd_translate(command);617}618 619static int rave_sp_default_cmd_translate(enum rave_sp_command command)620{621	/*622	 * All of the following command codes were taken from "Table :623	 * Communications Protocol Message Types" in section 3.3624	 * "MESSAGE TYPES" of Rave PIC24 ICD.625	 */626	switch (command) {627	case RAVE_SP_CMD_GET_FIRMWARE_VERSION:628		return 0x11;629	case RAVE_SP_CMD_GET_BOOTLOADER_VERSION:630		return 0x12;631	case RAVE_SP_CMD_BOOT_SOURCE:632		return 0x14;633	case RAVE_SP_CMD_SW_WDT:634		return 0x1C;635	case RAVE_SP_CMD_PET_WDT:636		return 0x1D;637	case RAVE_SP_CMD_RESET:638		return 0x1E;639	case RAVE_SP_CMD_RESET_REASON:640		return 0x1F;641	case RAVE_SP_CMD_RMB_EEPROM:642		return 0x20;643	default:644		return -EINVAL;645	}646}647 648static const char *devm_rave_sp_version(struct device *dev,649					struct rave_sp_version *version)650{651	/*652	 * NOTE: The format string below uses %02d to display u16653	 * intentionally for the sake of backwards compatibility with654	 * legacy software.655	 */656	return devm_kasprintf(dev, GFP_KERNEL, "%02d%02d%02d.%c%c\n",657			      version->hardware,658			      le16_to_cpu(version->major),659			      version->minor,660			      version->letter[0],661			      version->letter[1]);662}663 664static int rave_sp_rdu1_get_status(struct rave_sp *sp,665				   struct rave_sp_status *status)666{667	u8 cmd[] = {668		[0] = RAVE_SP_CMD_STATUS,669		[1] = 0670	};671 672	return rave_sp_exec(sp, cmd, sizeof(cmd), status, sizeof(*status));673}674 675static int rave_sp_emulated_get_status(struct rave_sp *sp,676				       struct rave_sp_status *status)677{678	u8 cmd[] = {679		[0] = RAVE_SP_CMD_GET_FIRMWARE_VERSION,680		[1] = 0,681	};682	int ret;683 684	ret = rave_sp_exec(sp, cmd, sizeof(cmd), &status->firmware_version,685			   sizeof(status->firmware_version));686	if (ret)687		return ret;688 689	cmd[0] = RAVE_SP_CMD_GET_BOOTLOADER_VERSION;690	return rave_sp_exec(sp, cmd, sizeof(cmd), &status->bootloader_version,691			    sizeof(status->bootloader_version));692}693 694static int rave_sp_get_status(struct rave_sp *sp)695{696	struct device *dev = &sp->serdev->dev;697	struct rave_sp_status status;698	const char *version;699	int ret;700 701	ret = sp->variant->cmd.get_status(sp, &status);702	if (ret)703		return ret;704 705	version = devm_rave_sp_version(dev, &status.firmware_version);706	if (!version)707		return -ENOMEM;708 709	sp->part_number_firmware = version;710 711	version = devm_rave_sp_version(dev, &status.bootloader_version);712	if (!version)713		return -ENOMEM;714 715	sp->part_number_bootloader = version;716 717	return 0;718}719 720static const struct rave_sp_checksum rave_sp_checksum_8b2c = {721	.length     = 1,722	.subroutine = csum_8b2c,723};724 725static const struct rave_sp_checksum rave_sp_checksum_ccitt = {726	.length     = 2,727	.subroutine = csum_ccitt,728};729 730static const struct rave_sp_variant rave_sp_legacy = {731	.checksum = &rave_sp_checksum_ccitt,732	.cmd = {733		.translate = rave_sp_default_cmd_translate,734		.get_status = rave_sp_emulated_get_status,735	},736};737 738static const struct rave_sp_variant rave_sp_rdu1 = {739	.checksum = &rave_sp_checksum_8b2c,740	.cmd = {741		.translate = rave_sp_rdu1_cmd_translate,742		.get_status = rave_sp_rdu1_get_status,743	},744};745 746static const struct rave_sp_variant rave_sp_rdu2 = {747	.checksum = &rave_sp_checksum_ccitt,748	.cmd = {749		.translate = rave_sp_rdu2_cmd_translate,750		.get_status = rave_sp_emulated_get_status,751	},752};753 754static const struct of_device_id rave_sp_dt_ids[] = {755	{ .compatible = "zii,rave-sp-niu",  .data = &rave_sp_legacy },756	{ .compatible = "zii,rave-sp-mezz", .data = &rave_sp_legacy },757	{ .compatible = "zii,rave-sp-esb",  .data = &rave_sp_legacy },758	{ .compatible = "zii,rave-sp-rdu1", .data = &rave_sp_rdu1   },759	{ .compatible = "zii,rave-sp-rdu2", .data = &rave_sp_rdu2   },760	{ /* sentinel */ }761};762 763static const struct serdev_device_ops rave_sp_serdev_device_ops = {764	.receive_buf  = rave_sp_receive_buf,765	.write_wakeup = serdev_device_write_wakeup,766};767 768static int rave_sp_probe(struct serdev_device *serdev)769{770	struct device *dev = &serdev->dev;771	const char *unknown = "unknown\n";772	struct rave_sp *sp;773	u32 baud;774	int ret;775 776	if (of_property_read_u32(dev->of_node, "current-speed", &baud)) {777		dev_err(dev,778			"'current-speed' is not specified in device node\n");779		return -EINVAL;780	}781 782	sp = devm_kzalloc(dev, sizeof(*sp), GFP_KERNEL);783	if (!sp)784		return -ENOMEM;785 786	sp->serdev = serdev;787	dev_set_drvdata(dev, sp);788 789	sp->variant = of_device_get_match_data(dev);790	if (!sp->variant)791		return -ENODEV;792 793	mutex_init(&sp->bus_lock);794	mutex_init(&sp->reply_lock);795	BLOCKING_INIT_NOTIFIER_HEAD(&sp->event_notifier_list);796 797	serdev_device_set_client_ops(serdev, &rave_sp_serdev_device_ops);798	ret = devm_serdev_device_open(dev, serdev);799	if (ret)800		return ret;801 802	serdev_device_set_baudrate(serdev, baud);803	serdev_device_set_flow_control(serdev, false);804 805	ret = serdev_device_set_parity(serdev, SERDEV_PARITY_NONE);806	if (ret) {807		dev_err(dev, "Failed to set parity\n");808		return ret;809	}810 811	ret = rave_sp_get_status(sp);812	if (ret) {813		dev_warn(dev, "Failed to get firmware status: %d\n", ret);814		sp->part_number_firmware   = unknown;815		sp->part_number_bootloader = unknown;816	}817 818	/*819	 * Those strings already have a \n embedded, so there's no820	 * need to have one in format string.821	 */822	dev_info(dev, "Firmware version: %s",   sp->part_number_firmware);823	dev_info(dev, "Bootloader version: %s", sp->part_number_bootloader);824 825	return devm_of_platform_populate(dev);826}827 828MODULE_DEVICE_TABLE(of, rave_sp_dt_ids);829 830static struct serdev_device_driver rave_sp_drv = {831	.probe			= rave_sp_probe,832	.driver = {833		.name		= "rave-sp",834		.of_match_table	= rave_sp_dt_ids,835	},836};837module_serdev_device_driver(rave_sp_drv);838 839MODULE_LICENSE("GPL");840MODULE_AUTHOR("Andrey Vostrikov <andrey.vostrikov@cogentembedded.com>");841MODULE_AUTHOR("Nikita Yushchenko <nikita.yoush@cogentembedded.com>");842MODULE_AUTHOR("Andrey Smirnov <andrew.smirnov@gmail.com>");843MODULE_DESCRIPTION("RAVE SP core driver");844