diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/devicetree/bindings/spi/spi-sc18is602.txt | 23 | ||||
| -rw-r--r-- | Documentation/spi/spi-sc18is602 | 36 |
2 files changed, 59 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/spi/spi-sc18is602.txt b/Documentation/devicetree/bindings/spi/spi-sc18is602.txt new file mode 100644 index 000000000000..02f9033270a2 --- /dev/null +++ b/Documentation/devicetree/bindings/spi/spi-sc18is602.txt @@ -0,0 +1,23 @@ +NXP SC18IS602/SCIS603 + +Required properties: + - compatible : Should be one of + "nxp,sc18is602" + "nxp,sc18is602b" + "nxp,sc18is603" + - reg: I2C bus address + +Optional properties: + - clock-frequency : external oscillator clock frequency. If not + specified, the SC18IS602 default frequency (7372000) will be used. + +The clock-frequency property is relevant and needed only if the chip has an +external oscillator (SC18IS603). + +Example: + + sc18is603@28 { + compatible = "nxp,sc18is603"; + reg = <0x28>; + clock-frequency = <14744000>; + } diff --git a/Documentation/spi/spi-sc18is602 b/Documentation/spi/spi-sc18is602 new file mode 100644 index 000000000000..a45702865a38 --- /dev/null +++ b/Documentation/spi/spi-sc18is602 @@ -0,0 +1,36 @@ +Kernel driver spi-sc18is602 +=========================== + +Supported chips: + * NXP SI18IS602/602B/603 + Datasheet: http://www.nxp.com/documents/data_sheet/SC18IS602_602B_603.pdf + +Author: + Guenter Roeck <linux@roeck-us.net> + + +Description +----------- + +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 +instead. |