Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 42 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/eeprom/at25.txt b/Documentation/devicetree/bindings/eeprom/at25.txt
new file mode 100644
index 000000000..b3bde97dc
--- /dev/null
+++ b/Documentation/devicetree/bindings/eeprom/at25.txt
@@ -0,0 +1,42 @@
+EEPROMs (SPI) compatible with Atmel at25.
+
+Required properties:
+- compatible : Should be "<vendor>,<type>", and generic value "atmel,at25".
+  Example "<vendor>,<type>" values:
+    "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
+
+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;
+
+		pagesize = <64>;
+		size = <32768>;
+		address-width = <16>;
+	};