mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-24 13:13:57 +08:00
d6ae0d578d
Commit 002176db (misc: at25: Parse dt settings) added device tree
bindings the differ significantly in style from the I2C EEPROM
bindings and don't seem well vetted. Here I deprecate (but still
support) the "at25,*" properties, and add what I hope is a better
alternative. These new bindings also happen to be deployed in the
field and were previously submitted for consideration here:
https://lists.ozlabs.org/pipermail/devicetree-discuss/2012-May/015556.html
The advantages of the new bindings are that they are similar to the
I2C EEPROMs and they don't conflate read-only and the address width
modes in a binary encoded blob.
Signed-off-by: David Daney <david.daney@cavium.com>
Cc: Alexandre Pereira da Silva <aletes.xgr@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Michael Hennerich <michael.hennerich@analog.com>
Cc: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
36 lines
1.0 KiB
Plaintext
36 lines
1.0 KiB
Plaintext
EEPROMs (SPI) compatible with Atmel at25.
|
|
|
|
Required properties:
|
|
- compatible : "atmel,at25".
|
|
- reg : chip select number
|
|
- spi-max-frequency : max spi frequency to use
|
|
- pagesize : size of the eeprom page
|
|
- size : total eeprom size in bytes
|
|
- address-width : number of address bits (one of 8, 16, or 24)
|
|
|
|
Optional properties:
|
|
- spi-cpha : SPI shifted clock phase, as per spi-bus bindings.
|
|
- spi-cpol : SPI inverse clock polarity, as per spi-bus bindings.
|
|
- read-only : this parameter-less property disables writes to the eeprom
|
|
|
|
Obsolete legacy properties are can be used in place of "size", "pagesize",
|
|
"address-width", and "read-only":
|
|
- at25,byte-len : total eeprom size in bytes
|
|
- at25,addr-mode : addr-mode flags, as defined in include/linux/spi/eeprom.h
|
|
- at25,page-size : size of the eeprom page
|
|
|
|
Additional compatible properties are also allowed.
|
|
|
|
Example:
|
|
at25@0 {
|
|
compatible = "atmel,at25", "st,m95256";
|
|
reg = <0>
|
|
spi-max-frequency = <5000000>;
|
|
spi-cpha;
|
|
spi-cpol;
|
|
|
|
pagesize = <64>;
|
|
size = <32768>;
|
|
address-width = <16>;
|
|
};
|