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Guenter Roeck3ce88592012-08-18 09:06:27 -07001Kernel driver spi-sc18is602
2===========================
3
4Supported chips:
5 * NXP SI18IS602/602B/603
6 Datasheet: http://www.nxp.com/documents/data_sheet/SC18IS602_602B_603.pdf
7
8Author:
9 Guenter Roeck <linux@roeck-us.net>
10
11
12Description
13-----------
14
15This driver provides connects a NXP SC18IS602/603 I2C-bus to SPI bridge to the
16kernel's SPI core subsystem.
17
18The driver does not probe for supported chips, since the SI18IS602/603 does not
19support Chip ID registers. You will have to instantiate the devices explicitly.
20Please see Documentation/i2c/instantiating-devices for details.
21
22
23Usage Notes
24-----------
25
26This driver requires the I2C adapter driver to support raw I2C messages. I2C
27adapter drivers which can only handle the SMBus protocol are not supported.
28
29The maximum SPI message size supported by SC18IS602/603 is 200 bytes. Attempts
30to initiate longer transfers will fail with -EINVAL. EEPROM read operations and
31similar large accesses have to be split into multiple chunks of no more than
32200 bytes per SPI message (128 bytes of data per message is recommended). This
33means that programs such as "cp" or "od", which automatically use large block
34sizes to access a device, can not be used directly to read data from EEPROM.
35Programs such as dd, where the block size can be specified, should be used
36instead.