27 lines
1005 B
ReStructuredText
27 lines
1005 B
ReStructuredText
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==============================
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Linux I2C slave EEPROM backend
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==============================
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by Wolfram Sang <wsa@sang-engineering.com> in 2014-20
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This backend simulates an EEPROM on the connected I2C bus. Its memory contents
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can be accessed from userspace via this file located in sysfs::
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/sys/bus/i2c/devices/<device-directory>/slave-eeprom
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The following types are available: 24c02, 24c32, 24c64, and 24c512. Read-only
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variants are also supported. The name needed for instantiating has the form
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'slave-<type>[ro]'. Examples follow:
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24c02, read/write, address 0x64:
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# echo slave-24c02 0x1064 > /sys/bus/i2c/devices/i2c-1/new_device
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24c512, read-only, address 0x42:
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# echo slave-24c512ro 0x1042 > /sys/bus/i2c/devices/i2c-1/new_device
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You can also preload data during boot if a device-property named
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'firmware-name' contains a valid filename (DT or ACPI only).
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As of 2015, Linux doesn't support poll on binary sysfs files, so there is no
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notification when another master changed the content.
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