Convert the binding document for at25 EEPROMs from txt to yaml.

Signed-off-by: Christian Eggers <ceggers@arri.de>
---
On Tuesday, 4 August 2020, 00:12:06 CEST, Rob Herring wrote:

quoted

On Sun, Aug 02, 2020 at 07:46:26PM +0200, Christian Eggers wrote:

quoted

As there is virtually an infinite list of possible vendors and products
for such type of hardware, is there any value to use expressions like in
the at24 binding?

Maybe so, but there are only 4 compatible strings to document in the
tree. That's not a lot to cover and we already have some of them in
free-form text. If the infinite number becomes a problem we can always
address that later. I'm sure that less than infinite buyers/products
will prevent infinite producers.

Added the following devices to the new yaml binding:
- Examples from description of previous txt binding.
- Result of grepping .dts and .dtsi files for atmel,at25
- Devices I personally use (dts files not mainlined yet).

 .../devicetree/bindings/eeprom/at25.txt       |  46 +------
 .../devicetree/bindings/eeprom/at25.yaml      | 129 ++++++++++++++++++
 2 files changed, 130 insertions(+), 45 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/eeprom/at25.yaml

diff --git a/Documentation/devicetree/bindings/eeprom/at25.txt b/Documentation/devicetree/bindings/eeprom/at25.txt
index fe91ecf1f61b..d9ef7dc5fb8e 100644
--- a/Documentation/devicetree/bindings/eeprom/at25.txt
+++ b/Documentation/devicetree/bindings/eeprom/at25.txt

@@ -1,45 +1 @@
-EEPROMs (SPI) compatible with Atmel at25.
-
-Required properties:
-- compatible : Should be "<vendor>,<type>", and generic value "atmel,at25".
-  Example "<vendor>,<type>" values:
-    "anvo,anv32e61w"
-    "microchip,25lc040"
-    "st,m95m02"
-    "st,m95256"
-
-- 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, 9, 16, or 24).
-  For 9 bits, the MSB of the address is sent as bit 3 of the instruction
-  byte, before the address byte.
-
-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
-- wp-gpios : GPIO to which the write-protect pin of the chip is connected
-
-Obsolete legacy properties 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:
-	eeprom@0 {
-		compatible = "st,m95256", "atmel,at25";
-		reg = <0>;
-		spi-max-frequency = <5000000>;
-		spi-cpha;
-		spi-cpol;
-		wp-gpios = <&gpio1 3 0>;
-
-		pagesize = <64>;
-		size = <32768>;
-		address-width = <16>;
-	};
+This file has been moved to at25.yaml.