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Diffstat (limited to 'Documentation/spi/spi-sc18is602')
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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. | ||