7  *   Copyright (C) 2016 T-Platforms. All Rights Reserved.
36  * IDT PCIe-switch NTB Linux driver
39  * Serge Semin <fancer.lancer@gmail.com>, <Sergey.Semin@t-platforms.ru>
42  *           NOTE of the IDT 89HPESx SMBus-slave interface driver
44  * IDT PCIe-switches. IDT provides a simple SMBus interface to perform IO-
47  * binary sysfs-file in the device directory:
48  * /sys/bus/i2c/devices/<bus>-<devaddr>/eeprom
49  * In case if read-only flag is specified in the dts-node of device desription,
50  * User-space applications won't be able to write to the EEPROM sysfs-node.
52  * data of device CSRs. This driver exposes debugf-file to perform simple IO
54  * next file is created in the specific debugfs-directory:
56  * Format of the debugfs-node is:
57  * $ cat /sys/kernel/debug/idt_csr/<bus>-<devaddr>/<devname>;
60  * If User-space application wishes to change current CSR address,
61  * it can just write a proper value to the sysfs-file:
62  * $ echo "<CSR address>" > /sys/kernel/debug/idt_csr/<bus>-<devaddr>/<devname>
66  *        /sys/kernel/debug/idt_csr/<bus>-<devaddr>/<devname>;
81 #include <linux/i2c.h>
86 #define IDT_89HPESX_DESC	"IDT 89HPESx SMBus-slave interface driver"
92 MODULE_AUTHOR("T-platforms");
95  * csr_dbgdir - CSR read/write operations Debugfs directory
100  * struct idt_89hpesx_dev - IDT 89HPESx device data structure
102  * @eero:	EEPROM Read-only flag
107  * @iniccode:	Initialial command code value for IO-operations
115  * @client:	i2c client used to perform IO operations
117  * @ee_file:	EEPROM read/write sysfs-file
142  * struct idt_smb_seq - sequence of data to be read/written from/to IDT 89HPESx
144  * @bytecnt:	Byte count of operation
154  * struct idt_eeprom_seq - sequence of data to be read/written from/to EEPROM
168  * struct idt_csr_seq - sequence of data to be read/written from/to CSR
207  * @EEPROM_WR_CNT:	Bytes count to perform write operation
208  * @EEPROM_WRRD_CNT:	Bytes count to write before reading
209  * @EEPROM_RD_CNT:	Bytes count to perform read operation
212  * @EEPROM_TOUT:	Timeout before retry read operation if eeprom is busy
234  * @CSR_WR_CNT:		Bytes count to perform write operation
235  * @CSR_WRRD_CNT:	Bytes count to write before reading
236  * @CSR_RD_CNT:		Bytes count to perform read operation
266  * @idt_smb_safe:	Generate a retry loop on corresponding SMBus method
274 	} while (__retry-- && __sts < 0); \
279  *                         i2c bus level IO-operations
284  * idt_smb_write_byte() - SMBus write method when I2C_SMBUS_BYTE_DATA operation
296 	/* Loop over the supplied data sending byte one-by-one */  in idt_smb_write_byte()
297 	for (idx = 0; idx < seq->bytecnt; idx++) {  in idt_smb_write_byte()
299 		ccode = seq->ccode | CCODE_BYTE;  in idt_smb_write_byte()
302 		if (idx == seq->bytecnt - 1)  in idt_smb_write_byte()
306 		sts = idt_smb_safe(write_byte, pdev->client, ccode,  in idt_smb_write_byte()
307 			seq->data[idx]);  in idt_smb_write_byte()
316  * idt_smb_read_byte() - SMBus read method when I2C_SMBUS_BYTE_DATA operation
328 	/* Loop over the supplied buffer receiving byte one-by-one */  in idt_smb_read_byte()
329 	for (idx = 0; idx < seq->bytecnt; idx++) {  in idt_smb_read_byte()
331 		ccode = seq->ccode | CCODE_BYTE;  in idt_smb_read_byte()
334 		if (idx == seq->bytecnt - 1)  in idt_smb_read_byte()
338 		sts = idt_smb_safe(read_byte, pdev->client, ccode);  in idt_smb_read_byte()
342 		seq->data[idx] = (u8)sts;  in idt_smb_read_byte()
349  * idt_smb_write_word() - SMBus write method when I2C_SMBUS_BYTE_DATA and
361 	/* Calculate the even count of data to send */  in idt_smb_write_word()
362 	evencnt = seq->bytecnt - (seq->bytecnt % 2);  in idt_smb_write_word()
367 		ccode = seq->ccode | CCODE_WORD;  in idt_smb_write_word()
370 		if (idx == evencnt - 2)  in idt_smb_write_word()
374 		sts = idt_smb_safe(write_word, pdev->client, ccode,  in idt_smb_write_word()
375 			*(u16 *)&seq->data[idx]);  in idt_smb_write_word()
381 	if (seq->bytecnt != evencnt) {  in idt_smb_write_word()
383 		ccode = seq->ccode | CCODE_BYTE | CCODE_END;  in idt_smb_write_word()
388 		sts = idt_smb_safe(write_byte, pdev->client, ccode,  in idt_smb_write_word()
389 			seq->data[idx]);  in idt_smb_write_word()
398  * idt_smb_read_word() - SMBus read method when I2C_SMBUS_BYTE_DATA and
410 	/* Calculate the even count of data to send */  in idt_smb_read_word()
411 	evencnt = seq->bytecnt - (seq->bytecnt % 2);  in idt_smb_read_word()
416 		ccode = seq->ccode | CCODE_WORD;  in idt_smb_read_word()
419 		if (idx == evencnt - 2)  in idt_smb_read_word()
423 		sts = idt_smb_safe(read_word, pdev->client, ccode);  in idt_smb_read_word()
427 		*(u16 *)&seq->data[idx] = (u16)sts;  in idt_smb_read_word()
431 	if (seq->bytecnt != evencnt) {  in idt_smb_read_word()
433 		ccode = seq->ccode | CCODE_BYTE | CCODE_END;  in idt_smb_read_word()
438 		sts = idt_smb_safe(read_byte, pdev->client, ccode);  in idt_smb_read_word()
442 		seq->data[idx] = (u8)sts;  in idt_smb_read_word()
449  * idt_smb_write_block() - SMBus write method when I2C_SMBUS_BLOCK_DATA
460 	if (seq->bytecnt > I2C_SMBUS_BLOCK_MAX)  in idt_smb_write_block()
461 		return -EINVAL;  in idt_smb_write_block()
464 	ccode = seq->ccode | CCODE_BLOCK | CCODE_START | CCODE_END;  in idt_smb_write_block()
467 	return idt_smb_safe(write_block, pdev->client, ccode, seq->bytecnt,  in idt_smb_write_block()
468 		seq->data);  in idt_smb_write_block()
472  * idt_smb_read_block() - SMBus read method when I2C_SMBUS_BLOCK_DATA
484 	if (seq->bytecnt > I2C_SMBUS_BLOCK_MAX)  in idt_smb_read_block()
485 		return -EINVAL;  in idt_smb_read_block()
488 	ccode = seq->ccode | CCODE_BLOCK | CCODE_START | CCODE_END;  in idt_smb_read_block()
491 	sts = idt_smb_safe(read_block, pdev->client, ccode, seq->data);  in idt_smb_read_block()
492 	if (sts != seq->bytecnt)  in idt_smb_read_block()
493 		return (sts < 0 ? sts : -ENODATA);  in idt_smb_read_block()
499  * idt_smb_write_i2c_block() - SMBus write method when I2C_SMBUS_I2C_BLOCK_DATA
513 	if (seq->bytecnt > I2C_SMBUS_BLOCK_MAX)  in idt_smb_write_i2c_block()
514 		return -EINVAL;  in idt_smb_write_i2c_block()
517 	buf[0] = seq->bytecnt;  in idt_smb_write_i2c_block()
518 	memcpy(&buf[1], seq->data, seq->bytecnt);  in idt_smb_write_i2c_block()
521 	ccode = seq->ccode | CCODE_BLOCK | CCODE_START | CCODE_END;  in idt_smb_write_i2c_block()
524 	return idt_smb_safe(write_i2c_block, pdev->client, ccode,  in idt_smb_write_i2c_block()
525 		seq->bytecnt + 1, buf);  in idt_smb_write_i2c_block()
529  * idt_smb_read_i2c_block() - SMBus read method when I2C_SMBUS_I2C_BLOCK_DATA
544 	if (seq->bytecnt > I2C_SMBUS_BLOCK_MAX)  in idt_smb_read_i2c_block()
545 		return -EINVAL;  in idt_smb_read_i2c_block()
548 	ccode = seq->ccode | CCODE_BLOCK | CCODE_START | CCODE_END;  in idt_smb_read_i2c_block()
551 	sts = idt_smb_safe(read_i2c_block, pdev->client, ccode,  in idt_smb_read_i2c_block()
552 		seq->bytecnt + 1, buf);  in idt_smb_read_i2c_block()
553 	if (sts != seq->bytecnt + 1)  in idt_smb_read_i2c_block()
554 		return (sts < 0 ? sts : -ENODATA);  in idt_smb_read_i2c_block()
555 	if (buf[0] != seq->bytecnt)  in idt_smb_read_i2c_block()
556 		return -ENODATA;  in idt_smb_read_i2c_block()
559 	memcpy(seq->data, &buf[1], seq->bytecnt);  in idt_smb_read_i2c_block()
565  *                          EEPROM IO-operations
570  * idt_eeprom_read_byte() - read just one byte from EEPROM
578 	struct device *dev = &pdev->client->dev;  in idt_eeprom_read_byte()
581 	int ret, retry;  in idt_eeprom_read_byte()  local
584 	smbseq.ccode = pdev->iniccode | CCODE_EEPROM;  in idt_eeprom_read_byte()
591 	retry = RETRY_CNT;  in idt_eeprom_read_byte()
595 		eeseq.cmd = pdev->inieecmd | EEPROM_OP_READ;  in idt_eeprom_read_byte()
596 		eeseq.eeaddr = pdev->eeaddr;  in idt_eeprom_read_byte()
598 		ret = pdev->smb_write(pdev, &smbseq);  in idt_eeprom_read_byte()
607 		ret = pdev->smb_read(pdev, &smbseq);  in idt_eeprom_read_byte()
615 		if (retry && (eeseq.cmd & EEPROM_NAERR)) {  in idt_eeprom_read_byte()
616 			dev_dbg(dev, "EEPROM busy, retry reading after %d ms",  in idt_eeprom_read_byte()
627 			ret = -EREMOTEIO;  in idt_eeprom_read_byte()
634 	} while (retry--);  in idt_eeprom_read_byte()
641  * idt_eeprom_write() - EEPROM write operation
650 	struct device *dev = &pdev->client->dev;  in idt_eeprom_write()
657 	smbseq.ccode = pdev->iniccode | CCODE_EEPROM;  in idt_eeprom_write()
660 	/* Send data byte-by-byte, checking if it is successfully written */  in idt_eeprom_write()
663 		mutex_lock(&pdev->smb_mtx);  in idt_eeprom_write()
667 		eeseq.cmd = pdev->inieecmd | EEPROM_OP_WRITE;  in idt_eeprom_write()
668 		eeseq.eeaddr = pdev->eeaddr;  in idt_eeprom_write()
671 		ret = pdev->smb_write(pdev, &smbseq);  in idt_eeprom_write()
692 			ret = -EREMOTEIO;  in idt_eeprom_write()
698 		mutex_unlock(&pdev->smb_mtx);  in idt_eeprom_write()
707  * idt_eeprom_read() - EEPROM read operation
719 	/* Read data byte-by-byte, retrying if it wasn't successful */  in idt_eeprom_read()
722 		mutex_lock(&pdev->smb_mtx);  in idt_eeprom_read()
728 		mutex_unlock(&pdev->smb_mtx);  in idt_eeprom_read()
739  *                          CSR IO-operations
744  * idt_csr_write() - CSR write operation
752 	struct device *dev = &pdev->client->dev;  in idt_csr_write()
758 	smbseq.ccode = pdev->iniccode | CCODE_CSR;  in idt_csr_write()
762 	mutex_lock(&pdev->smb_mtx);  in idt_csr_write()
766 	csrseq.cmd = pdev->inicsrcmd | CSR_OP_WRITE;  in idt_csr_write()
769 	ret = pdev->smb_write(pdev, &smbseq);  in idt_csr_write()
778 	csrseq.cmd = pdev->inicsrcmd | CSR_OP_READ;  in idt_csr_write()
779 	ret = pdev->smb_write(pdev, &smbseq);  in idt_csr_write()
788 	ret = pdev->smb_read(pdev, &smbseq);  in idt_csr_write()
798 		ret = -EREMOTEIO;  in idt_csr_write()
804 	mutex_unlock(&pdev->smb_mtx);  in idt_csr_write()
810  * idt_csr_read() - CSR read operation
817 	struct device *dev = &pdev->client->dev;  in idt_csr_read()
823 	smbseq.ccode = pdev->iniccode | CCODE_CSR;  in idt_csr_read()
827 	mutex_lock(&pdev->smb_mtx);  in idt_csr_read()
831 	csrseq.cmd = pdev->inicsrcmd | CSR_OP_READ;  in idt_csr_read()
833 	ret = pdev->smb_write(pdev, &smbseq);  in idt_csr_read()
842 	ret = pdev->smb_read(pdev, &smbseq);  in idt_csr_read()
852 		ret = -EREMOTEIO;  in idt_csr_read()
861 	mutex_unlock(&pdev->smb_mtx);  in idt_csr_read()
867  *                          Sysfs/debugfs-nodes IO-operations
872  * eeprom_write() - EEPROM sysfs-node write callback
874  * @kobj:	Pointer to the kernel object related to the sysfs-node
878  * @count:	Number of bytes to write
882 			    char *buf, loff_t off, size_t count)  in eeprom_write()  argument
891 	ret = idt_eeprom_write(pdev, (u16)off, (u16)count, (u8 *)buf);  in eeprom_write()
892 	return (ret != 0 ? ret : count);  in eeprom_write()
896  * eeprom_read() - EEPROM sysfs-node read callback
898  * @kobj:	Pointer to the kernel object related to the sysfs-node
902  * @count:	Number of bytes to write
906 			   char *buf, loff_t off, size_t count)  in eeprom_read()  argument
915 	ret = idt_eeprom_read(pdev, (u16)off, (u16)count, (u8 *)buf);  in eeprom_read()
916 	return (ret != 0 ? ret : count);  in eeprom_read()
920  * idt_dbgfs_csr_write() - CSR debugfs-node write callback
923  * @count:	Size of the buffer
935 				   size_t count, loff_t *offp)  in idt_dbgfs_csr_write()  argument
937 	struct idt_89hpesx_dev *pdev = filep->private_data;  in idt_dbgfs_csr_write()
943 	/* Copy data from User-space */  in idt_dbgfs_csr_write()
944 	buf = kmalloc(count + 1, GFP_KERNEL);  in idt_dbgfs_csr_write()
946 		return -ENOMEM;  in idt_dbgfs_csr_write()
948 	ret = simple_write_to_buffer(buf, count, offp, ubuf, count);  in idt_dbgfs_csr_write()
951 	buf[count] = 0;  in idt_dbgfs_csr_write()
954 	colon_ch = strnchr(buf, count, ':');  in idt_dbgfs_csr_write()
963 		csraddr_len = colon_ch - buf;  in idt_dbgfs_csr_write()
967 			ret = -ENOMEM;  in idt_dbgfs_csr_write()
977 		csraddr_len = strnlen(csraddr_str, count);  in idt_dbgfs_csr_write()
988 		ret = -EINVAL;  in idt_dbgfs_csr_write()
993 	pdev->csr = (csraddr >> 2);  in idt_dbgfs_csr_write()
1001 		ret = idt_csr_write(pdev, pdev->csr, csrval);  in idt_dbgfs_csr_write()
1011 	/* Free buffer allocated for data retrieved from User-space */  in idt_dbgfs_csr_write()
1015 	return (ret != 0 ? ret : count);  in idt_dbgfs_csr_write()
1019  * idt_dbgfs_csr_read() - CSR debugfs-node read callback
1022  * @count:	Size of the buffer
1029 				  size_t count, loff_t *offp)  in idt_dbgfs_csr_read()  argument
1031 	struct idt_89hpesx_dev *pdev = filep->private_data;  in idt_dbgfs_csr_read()
1037 	ret = idt_csr_read(pdev, pdev->csr, &csrval);  in idt_dbgfs_csr_read()
1042 	csraddr = ((u32)pdev->csr << 2);  in idt_dbgfs_csr_read()
1048 	/* Copy data to User-space */  in idt_dbgfs_csr_read()
1049 	return simple_read_from_buffer(ubuf, count, offp, buf, size);  in idt_dbgfs_csr_read()
1053  * eeprom_attribute - EEPROM sysfs-node attributes
1056  * be read-only as well if the corresponding flag is specified in OF node.
1061  * csr_dbgfs_ops - CSR debugfs-node read/write operations
1076  * idt_set_defval() - disable EEPROM access by default
1082 	pdev->eesize = 0;  in idt_set_defval()
1083 	pdev->eero = true;  in idt_set_defval()
1084 	pdev->inieecmd = 0;  in idt_set_defval()
1085 	pdev->eeaddr = 0;  in idt_set_defval()
1091  * idt_ee_match_id() - check whether the node belongs to compatible EEPROMs
1107 	while (id->name[0]) {  in idt_ee_match_id()
1108 		if (strcmp(devname, id->name) == 0)  in idt_ee_match_id()
1116  * idt_get_fw_data() - get IDT i2c-device parameters from device tree
1121 	struct device *dev = &pdev->client->dev;  in idt_get_fw_data()
1144 	pdev->eesize = (u32)ee_id->driver_data;  in idt_get_fw_data()
1151 		pdev->inieecmd = 0;  in idt_get_fw_data()
1152 		pdev->eeaddr = EEPROM_DEF_ADDR << 1;  in idt_get_fw_data()
1154 		pdev->inieecmd = EEPROM_USA;  in idt_get_fw_data()
1155 		pdev->eeaddr = eeprom_addr << 1;  in idt_get_fw_data()
1158 	/* Check EEPROM 'read-only' flag */  in idt_get_fw_data()
1159 	if (fwnode_property_read_bool(fwnode, "read-only"))  in idt_get_fw_data()
1160 		pdev->eero = true;  in idt_get_fw_data()
1161 	else /* if (!fwnode_property_read_bool(node, "read-only")) */  in idt_get_fw_data()
1162 		pdev->eero = false;  in idt_get_fw_data()
1165 		pdev->eesize, pdev->eeaddr);  in idt_get_fw_data()
1169  * idt_create_pdev() - create and init data structure of the driver
1170  * @client:	i2c client of IDT PCIe-switch device
1177 	pdev = devm_kmalloc(&client->dev, sizeof(struct idt_89hpesx_dev),  in idt_create_pdev()
1180 		return ERR_PTR(-ENOMEM);  in idt_create_pdev()
1183 	pdev->client = client;  in idt_create_pdev()
1189 	/* Initialize basic CSR CMD field - use full DWORD-sized r/w ops */  in idt_create_pdev()
1190 	pdev->inicsrcmd = CSR_DWE;  in idt_create_pdev()
1191 	pdev->csr = CSR_DEF;  in idt_create_pdev()
1194 	if (i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_PEC)) {  in idt_create_pdev()
1195 		pdev->iniccode = CCODE_PEC;  in idt_create_pdev()
1196 		client->flags |= I2C_CLIENT_PEC;  in idt_create_pdev()
1198 		pdev->iniccode = 0;  in idt_create_pdev()
1205  * idt_free_pdev() - free data structure of the driver
1211 	i2c_set_clientdata(pdev->client, NULL);  in idt_free_pdev()
1215  * idt_set_smbus_ops() - set supported SMBus operations
1221 	struct i2c_adapter *adapter = pdev->client->adapter;  in idt_set_smbus_ops()
1222 	struct device *dev = &pdev->client->dev;  in idt_set_smbus_ops()
1224 	/* Check i2c adapter read functionality */  in idt_set_smbus_ops()
1227 		pdev->smb_read = idt_smb_read_block;  in idt_set_smbus_ops()
1228 		dev_dbg(dev, "SMBus block-read op chosen");  in idt_set_smbus_ops()
1231 		pdev->smb_read = idt_smb_read_i2c_block;  in idt_set_smbus_ops()
1232 		dev_dbg(dev, "SMBus i2c-block-read op chosen");  in idt_set_smbus_ops()
1237 		pdev->smb_read = idt_smb_read_word;  in idt_set_smbus_ops()
1241 		pdev->smb_read = idt_smb_read_byte;  in idt_set_smbus_ops()
1245 		return -EPFNOSUPPORT;  in idt_set_smbus_ops()
1248 	/* Check i2c adapter write functionality */  in idt_set_smbus_ops()
1251 		pdev->smb_write = idt_smb_write_block;  in idt_set_smbus_ops()
1252 		dev_dbg(dev, "SMBus block-write op chosen");  in idt_set_smbus_ops()
1255 		pdev->smb_write = idt_smb_write_i2c_block;  in idt_set_smbus_ops()
1256 		dev_dbg(dev, "SMBus i2c-block-write op chosen");  in idt_set_smbus_ops()
1261 		pdev->smb_write = idt_smb_write_word;  in idt_set_smbus_ops()
1265 		pdev->smb_write = idt_smb_write_byte;  in idt_set_smbus_ops()
1269 		return -EPFNOSUPPORT;  in idt_set_smbus_ops()
1273 	mutex_init(&pdev->smb_mtx);  in idt_set_smbus_ops()
1279  * idt_check_dev() - check whether it's really IDT 89HPESx device
1281  * Return status of i2c adapter check operation
1285 	struct device *dev = &pdev->client->dev;  in idt_check_dev()
1299 		return -ENODEV;  in idt_check_dev()
1309  * idt_create_sysfs_files() - create sysfs attribute files
1315 	struct device *dev = &pdev->client->dev;  in idt_create_sysfs_files()
1319 	if (pdev->eesize == 0) {  in idt_create_sysfs_files()
1320 		dev_dbg(dev, "Skip creating sysfs-files");  in idt_create_sysfs_files()
1325 	pdev->ee_file = devm_kmalloc(dev, sizeof(*pdev->ee_file), GFP_KERNEL);  in idt_create_sysfs_files()
1326 	if (!pdev->ee_file)  in idt_create_sysfs_files()
1327 		return -ENOMEM;  in idt_create_sysfs_files()
1330 	memcpy(pdev->ee_file, &bin_attr_eeprom, sizeof(*pdev->ee_file));  in idt_create_sysfs_files()
1332 	/* In case of read-only EEPROM get rid of write ability */  in idt_create_sysfs_files()
1333 	if (pdev->eero) {  in idt_create_sysfs_files()
1334 		pdev->ee_file->attr.mode &= ~0200;  in idt_create_sysfs_files()
1335 		pdev->ee_file->write = NULL;  in idt_create_sysfs_files()
1338 	pdev->ee_file->size = pdev->eesize;  in idt_create_sysfs_files()
1339 	ret = sysfs_create_bin_file(&dev->kobj, pdev->ee_file);  in idt_create_sysfs_files()
1341 		dev_err(dev, "Failed to create EEPROM sysfs-node");  in idt_create_sysfs_files()
1349  * idt_remove_sysfs_files() - remove sysfs attribute files
1354 	struct device *dev = &pdev->client->dev;  in idt_remove_sysfs_files()
1357 	if (pdev->eesize == 0)  in idt_remove_sysfs_files()
1361 	sysfs_remove_bin_file(&dev->kobj, pdev->ee_file);  in idt_remove_sysfs_files()
1365  * idt_create_dbgfs_files() - create debugfs files
1371 	struct i2c_client *cli = pdev->client;  in idt_create_dbgfs_files()
1375 	snprintf(fname, CSRNAME_LEN, "%d-%04hx", cli->adapter->nr, cli->addr);  in idt_create_dbgfs_files()
1376 	pdev->csr_dir = debugfs_create_dir(fname, csr_dbgdir);  in idt_create_dbgfs_files()
1379 	debugfs_create_file(cli->name, 0600, pdev->csr_dir, pdev,  in idt_create_dbgfs_files()
1384  * idt_remove_dbgfs_files() - remove debugfs files
1389 	/* Remove CSR directory and it sysfs-node */  in idt_remove_dbgfs_files()
1390 	debugfs_remove_recursive(pdev->csr_dir);  in idt_remove_dbgfs_files()
1394  * idt_probe() - IDT 89HPESx driver probe() callback method
1433  * idt_remove() - IDT 89HPESx driver remove() callback method
1452  * ee_ids - array of supported EEPROMs
1462 MODULE_DEVICE_TABLE(i2c, ee_ids);
1465  * idt_ids - supported IDT 89HPESx devices
1499 	/* { "89hpes3t3", 0 }, // No SMBus-slave iface */
1502 	/* { "89hpes4t4", 0 }, // No SMBus-slave iface */
1522 MODULE_DEVICE_TABLE(i2c, idt_ids);
1581  * idt_driver - IDT 89HPESx driver structure
1594  * idt_init() - IDT 89HPESx driver init() callback method
1602 	/* Add new i2c-device driver */  in idt_init()
1608  * idt_exit() - IDT 89HPESx driver exit() callback method
1615 	/* Unregister i2c-device driver */  in idt_exit()