| ============================== |
| Linux I2C slave EEPROM backend |
| ============================== |
| |
| by Wolfram Sang <wsa@sang-engineering.com> in 2014-20 |
| |
| This backend simulates an EEPROM on the connected I2C bus. Its memory contents |
| can be accessed from userspace via this file located in sysfs:: |
| |
| /sys/bus/i2c/devices/<device-directory>/slave-eeprom |
| |
| The following types are available: 24c02, 24c32, 24c64, and 24c512. Read-only |
| variants are also supported. The name needed for instantiating has the form |
| 'slave-<type>[ro]'. Examples follow: |
| |
| 24c02, read/write, address 0x64: |
| # echo slave-24c02 0x1064 > /sys/bus/i2c/devices/i2c-1/new_device |
| |
| 24c512, read-only, address 0x42: |
| # echo slave-24c512ro 0x1042 > /sys/bus/i2c/devices/i2c-1/new_device |
| |
| You can also preload data during boot if a device-property named |
| 'firmware-name' contains a valid filename (DT or ACPI only). |
| |
| As of 2015, Linux doesn't support poll on binary sysfs files, so there is no |
| notification when another master changed the content. |
