Documentation/spi/spi-sc18is602

   1 Kernel driver spi-sc18is602
   2 ===========================
   3
   4 Supported chips:
   5   * NXP SI18IS602/602B/603
   6     Datasheet: http://www.nxp.com/documents/data_sheet/SC18IS602_602B_603.pdf
   7
   8 Author:
   9         Guenter Roeck <linux@roeck-us.net>
  10
  11
  12 Description
  13 -----------
  14
  15 This driver provides connects a NXP SC18IS602/603 I2C-bus to SPI bridge to the
  16 kernel's SPI core subsystem.
  17
  18 The driver does not probe for supported chips, since the SI18IS602/603 does not
  19 support Chip ID registers. You will have to instantiate the devices explicitly.
  20 Please see Documentation/i2c/instantiating-devices for details.
  21
  22
  23 Usage Notes
  24 -----------
  25
  26 This driver requires the I2C adapter driver to support raw I2C messages. I2C
  27 adapter drivers which can only handle the SMBus protocol are not supported.
  28
  29 The maximum SPI message size supported by SC18IS602/603 is 200 bytes. Attempts
  30 to initiate longer transfers will fail with -EINVAL. EEPROM read operations and
  31 similar large accesses have to be split into multiple chunks of no more than
  32 200 bytes per SPI message (128 bytes of data per message is recommended). This
  33 means that programs such as "cp" or "od", which automatically use large block
  34 sizes to access a device, can not be used directly to read data from EEPROM.
  35 Programs such as dd, where the block size can be specified, should be used
  36 instead.