| Message ID | 20200628185426.5733-1-wsa+renesas@sang-engineering.com (mailing list archive) |
|---|---|
| State | Accepted |
| Delegated to: | Geert Uytterhoeven |
| Headers | show |
| Series | [v2] i2c: slave-eeprom: update documentation | expand |
Hi Wolfram, Thanks for your work. On 2020-06-28 20:54:26 +0200, Wolfram Sang wrote: > Add more details which have either been missing ever since or describe > recent additions. > > Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se> > --- > > Change since v1: add 'help' keyword to the Kconfig explanation > > Documentation/i2c/slave-eeprom-backend.rst | 22 +++++++++++++++++----- > drivers/i2c/Kconfig | 4 ++++ > 2 files changed, 21 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. > diff --git a/drivers/i2c/Kconfig b/drivers/i2c/Kconfig > index ef39c83aaf33..dbcbb8a6024e 100644 > --- a/drivers/i2c/Kconfig > +++ b/drivers/i2c/Kconfig > @@ -119,6 +119,10 @@ if I2C_SLAVE > config I2C_SLAVE_EEPROM > tristate "I2C eeprom slave driver" > > + help > + This backend makes Linux behave like an I2C EEPROM. Please read > + Documentation/i2c/slave-eeprom-backend.rst for further details. > + > endif > > config I2C_DEBUG_CORE > -- > 2.20.1 >
Hi Wolfram, On 28/06/20 20:54, Wolfram Sang wrote: > Add more details which have either been missing ever since or describe > recent additions. > > Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Luca Ceresoli <luca@lucaceresoli.net>
On Sun, Jun 28, 2020 at 08:54:26PM +0200, Wolfram Sang wrote: > Add more details which have either been missing ever since or describe > recent additions. > > Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Applied to for-current, thanks!
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. diff --git a/drivers/i2c/Kconfig b/drivers/i2c/Kconfig index ef39c83aaf33..dbcbb8a6024e 100644 --- a/drivers/i2c/Kconfig +++ b/drivers/i2c/Kconfig @@ -119,6 +119,10 @@ if I2C_SLAVE config I2C_SLAVE_EEPROM tristate "I2C eeprom slave driver" + help + This backend makes Linux behave like an I2C EEPROM. Please read + Documentation/i2c/slave-eeprom-backend.rst for further details. + endif config I2C_DEBUG_CORE
Add more details which have either been missing ever since or describe recent additions. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> --- Change since v1: add 'help' keyword to the Kconfig explanation Documentation/i2c/slave-eeprom-backend.rst | 22 +++++++++++++++++----- drivers/i2c/Kconfig | 4 ++++ 2 files changed, 21 insertions(+), 5 deletions(-)