path: root/Documentation/spi/spi-sc18is602
diff options
authorGuenter Roeck <linux@roeck-us.net>2012-08-18 09:06:27 -0700
committerMark Brown <broonie@opensource.wolfsonmicro.com>2012-08-22 19:34:51 +0100
commit3ce8859e2e72713d3619285cab609d05c3591fc4 (patch)
treec5ac44e96198137f34559e1fd493c9d6b02960b1 /Documentation/spi/spi-sc18is602
parent21879213652aca6e3fe250fc8e02c68e71c5e18a (diff)
spi: Master driver for NXP SC18IS602/603
This driver adds support for NXP SC18IS602/603 I2C to SPI bus bridge. Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
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+Kernel driver spi-sc18is602
+Supported chips:
+ * NXP SI18IS602/602B/603
+ Datasheet: http://www.nxp.com/documents/data_sheet/SC18IS602_602B_603.pdf
+ Guenter Roeck <linux@roeck-us.net>
+This driver provides connects a NXP SC18IS602/603 I2C-bus to SPI bridge to the
+kernel's SPI core subsystem.
+The driver does not probe for supported chips, since the SI18IS602/603 does not
+support Chip ID registers. You will have to instantiate the devices explicitly.
+Please see Documentation/i2c/instantiating-devices for details.
+Usage Notes
+This driver requires the I2C adapter driver to support raw I2C messages. I2C
+adapter drivers which can only handle the SMBus protocol are not supported.
+The maximum SPI message size supported by SC18IS602/603 is 200 bytes. Attempts
+to initiate longer transfers will fail with -EINVAL. EEPROM read operations and
+similar large accesses have to be split into multiple chunks of no more than
+200 bytes per SPI message (128 bytes of data per message is recommended). This
+means that programs such as "cp" or "od", which automatically use large block
+sizes to access a device, can not be used directly to read data from EEPROM.
+Programs such as dd, where the block size can be specified, should be used