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-rw-r--r--doc/device-tree-bindings/mtd/spi/spi-flash.txt25
-rw-r--r--doc/device-tree-bindings/spi/soft-spi.txt34
2 files changed, 59 insertions, 0 deletions
diff --git a/doc/device-tree-bindings/mtd/spi/spi-flash.txt b/doc/device-tree-bindings/mtd/spi/spi-flash.txt
new file mode 100644
index 0000000..85522d8
--- /dev/null
+++ b/doc/device-tree-bindings/mtd/spi/spi-flash.txt
@@ -0,0 +1,25 @@
+* MTD SPI driver for serial flash chips
+
+Required properties:
+- #address-cells, #size-cells : Must be present if the device has sub-nodes
+ representing partitions.
+- compatible : Should be the manufacturer and the name of the chip. Bear in
+ mind that the DT binding is not U-Boot-only, but in case of
+ U-Boot, see spi_flash_params_table table in
+ drivers/mtd/spi/sf_params.c for the list of supported chips.
+- reg : Chip-Select number
+- spi-max-frequency : Maximum frequency of the SPI bus the chip can operate at
+
+Optional properties:
+ - memory-map : Address and size of the flash, if memory mapped. This may
+ apply to Intel chipsets, which tend to memory-map flash.
+
+Example:
+
+ flash: m25p80@0 {
+ #address-cells = <1>;
+ #size-cells = <1>;
+ compatible = "spansion,m25p80";
+ reg = <0>;
+ spi-max-frequency = <40000000>;
+ };
diff --git a/doc/device-tree-bindings/spi/soft-spi.txt b/doc/device-tree-bindings/spi/soft-spi.txt
new file mode 100644
index 0000000..d09c1a5
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+++ b/doc/device-tree-bindings/spi/soft-spi.txt
@@ -0,0 +1,34 @@
+Soft SPI
+
+The soft SPI bus implementation allows the use of GPIO pins to simulate a
+SPI bus. No SPI host is required for this to work. The down-side is that the
+performance will typically be much lower than a real SPI bus.
+
+The soft SPI node requires the following properties:
+
+compatible: "u-boot,soft-spi"
+soft_spi_cs: GPIO number to use for SPI chip select (output)
+soft_spi_sclk: GPIO number to use for SPI clock (output)
+soft_spi_mosi: GPIO number to use for SPI MOSI line (output)
+soft_spi_miso GPIO number to use for SPI MISO line (input)
+spi-delay-us: Number of microseconds of delay between each CS transition
+
+The GPIOs should be specified as required by the GPIO controller referenced.
+The first cell holds the phandle of the controller and the second cell
+typically holds the GPIO number.
+
+
+Example:
+
+ soft-spi {
+ compatible = "u-boot,soft-spi";
+ cs-gpio = <&gpio 235 0>; /* Y43 */
+ sclk-gpio = <&gpio 225 0>; /* Y31 */
+ mosi-gpio = <&gpio 227 0>; /* Y33 */
+ miso-gpio = <&gpio 224 0>; /* Y30 */
+ spi-delay-us = <1>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ cs@0 {
+ };
+ };