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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2020-07-05 10:35:01 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-07-05 10:35:01 -0700 |
| commit | 7783485401e802b4802c93cb1b23deb7f0d168a4 (patch) | |
| tree | b841bb4488efc3b4e2e11a578f5d073b5d0eda44 /Documentation | |
| parent | 45a5ac7a5cc3c71739d240c422c3818a5bc97fc4 (diff) | |
| parent | 597911287fcd13c3a4b4aa3e0a52b33d431e0a8e (diff) | |
| download | linux-7783485401e802b4802c93cb1b23deb7f0d168a4.tar.bz2 | |
Merge branch 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c fixes from Wolfram Sang:
"The usual driver fixes and documentation updates"
* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: mlxcpld: check correct size of maximum RECV_LEN packet
i2c: add Kconfig help text for slave mode
i2c: slave-eeprom: update documentation
i2c: eg20t: Load module automatically if ID matches
i2c: designware: platdrv: Set class based on DMI
i2c: algo-pca: Add 0x78 as SCL stuck low status for PCA9665
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/i2c/slave-eeprom-backend.rst | 22 |
1 files changed, 17 insertions, 5 deletions
diff --git a/Documentation/i2c/slave-eeprom-backend.rst b/Documentation/i2c/slave-eeprom-backend.rst index 0b8cd83698e0..38d951f10302 100644 --- a/Documentation/i2c/slave-eeprom-backend.rst +++ b/Documentation/i2c/slave-eeprom-backend.rst @@ -1,14 +1,26 @@ ============================== -Linux I2C slave eeprom backend +Linux I2C slave EEPROM backend ============================== -by Wolfram Sang <wsa@sang-engineering.com> in 2014-15 +by Wolfram Sang <wsa@sang-engineering.com> in 2014-20 -This is a proof-of-concept backend which acts like an EEPROM on the connected -I2C bus. The memory contents can be modified from userspace via this file -located in sysfs:: +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. |