diff options
Diffstat (limited to 'meta-rcar-gen3-adas/recipes-kernel/linux/linux-renesas/0083-spi-Document-DT-bindings-for-SPI-controllers-in-slav.patch')
| -rw-r--r-- | meta-rcar-gen3-adas/recipes-kernel/linux/linux-renesas/0083-spi-Document-DT-bindings-for-SPI-controllers-in-slav.patch | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/meta-rcar-gen3-adas/recipes-kernel/linux/linux-renesas/0083-spi-Document-DT-bindings-for-SPI-controllers-in-slav.patch b/meta-rcar-gen3-adas/recipes-kernel/linux/linux-renesas/0083-spi-Document-DT-bindings-for-SPI-controllers-in-slav.patch new file mode 100644 index 0000000..0266378 --- /dev/null +++ b/meta-rcar-gen3-adas/recipes-kernel/linux/linux-renesas/0083-spi-Document-DT-bindings-for-SPI-controllers-in-slav.patch @@ -0,0 +1,118 @@ +From c71da12ba9738ac1441fb431100cb03662ba9ac1 Mon Sep 17 00:00:00 2001 +From: Geert Uytterhoeven <geert+renesas@glider.be> +Date: Fri, 17 Jun 2016 18:05:32 +0200 +Subject: [PATCH 1/7] spi: Document DT bindings for SPI controllers in slave + mode + +Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> +Reviewed-by: Rob Herring <robh@kernel.org> +--- + Documentation/devicetree/bindings/spi/spi-bus.txt | 76 ++++++++++++--------- + 1 file changed, 45 insertions(+), 31 deletions(-) + +diff --git a/Documentation/devicetree/bindings/spi/spi-bus.txt b/Documentation/devicetree/bindings/spi/spi-bus.txt +index 4b1d6e7..1f6e86f 100644 +--- a/Documentation/devicetree/bindings/spi/spi-bus.txt ++++ b/Documentation/devicetree/bindings/spi/spi-bus.txt +@@ -1,17 +1,23 @@ + SPI (Serial Peripheral Interface) busses + +-SPI busses can be described with a node for the SPI master device +-and a set of child nodes for each SPI slave on the bus. For this +-discussion, it is assumed that the system's SPI controller is in +-SPI master mode. This binding does not describe SPI controllers +-in slave mode. ++SPI busses can be described with a node for the SPI controller device ++and a set of child nodes for each SPI slave on the bus. The system's SPI ++controller may be described for use in SPI master mode or in SPI slave mode, ++but not for both at the same time. + +-The SPI master node requires the following properties: ++The SPI controller node requires the following properties: ++- compatible - Name of SPI bus controller following generic names ++ recommended practice. ++ ++In master mode, the SPI controller node requires the following additional ++properties: + - #address-cells - number of cells required to define a chip select + address on the SPI bus. + - #size-cells - should be zero. +-- compatible - name of SPI bus controller following generic names +- recommended practice. ++ ++In slave mode, the SPI controller node requires one additional property: ++- spi-slave - Empty property. ++ + No other properties are required in the SPI bus node. It is assumed + that a driver for an SPI bus device will understand that it is an SPI bus. + However, the binding does not attempt to define the specific method for +@@ -21,7 +27,7 @@ assumption that board specific platform code will be used to manage + chip selects. Individual drivers can define additional properties to + support describing the chip select layout. + +-Optional properties: ++Optional properties (master mode only): + - cs-gpios - gpios chip select. + - num-cs - total number of chipselects. + +@@ -41,28 +47,36 @@ cs1 : native + cs2 : &gpio1 1 0 + cs3 : &gpio1 2 0 + +-SPI slave nodes must be children of the SPI master node and can +-contain the following properties. +-- reg - (required) chip select address of device. +-- compatible - (required) name of SPI device following generic names +- recommended practice. +-- spi-max-frequency - (required) Maximum SPI clocking speed of device in Hz. +-- spi-cpol - (optional) Empty property indicating device requires +- inverse clock polarity (CPOL) mode. +-- spi-cpha - (optional) Empty property indicating device requires +- shifted clock phase (CPHA) mode. +-- spi-cs-high - (optional) Empty property indicating device requires +- chip select active high. +-- spi-3wire - (optional) Empty property indicating device requires +- 3-wire mode. +-- spi-lsb-first - (optional) Empty property indicating device requires +- LSB first mode. +-- spi-tx-bus-width - (optional) The bus width (number of data wires) that is +- used for MOSI. Defaults to 1 if not present. +-- spi-rx-bus-width - (optional) The bus width (number of data wires) that is +- used for MISO. Defaults to 1 if not present. +-- spi-rx-delay-us - (optional) Microsecond delay after a read transfer. +-- spi-tx-delay-us - (optional) Microsecond delay after a write transfer. ++ ++SPI slave nodes must be children of the SPI controller node. ++ ++In master mode, one or more slave nodes (up to the number of chip selects) can ++be present. Required properties are: ++- compatible - Name of SPI device following generic names recommended ++ practice. ++- reg - Chip select address of device. ++- spi-max-frequency - Maximum SPI clocking speed of device in Hz. ++ ++In slave mode, the (single) slave node is optional. ++If present, it must be called "slave". Required properties are: ++- compatible - Name of SPI device following generic names recommended ++ practice. ++ ++All slave nodes can contain the following optional properties: ++- spi-cpol - Empty property indicating device requires inverse clock ++ polarity (CPOL) mode. ++- spi-cpha - Empty property indicating device requires shifted clock ++ phase (CPHA) mode. ++- spi-cs-high - Empty property indicating device requires chip select ++ active high. ++- spi-3wire - Empty property indicating device requires 3-wire mode. ++- spi-lsb-first - Empty property indicating device requires LSB first mode. ++- spi-tx-bus-width - The bus width (number of data wires) that is used for MOSI. ++ Defaults to 1 if not present. ++- spi-rx-bus-width - The bus width (number of data wires) that is used for MISO. ++ Defaults to 1 if not present. ++- spi-rx-delay-us - Microsecond delay after a read transfer. ++- spi-tx-delay-us - Microsecond delay after a write transfer. + + Some SPI controllers and devices support Dual and Quad SPI transfer mode. + It allows data in the SPI system to be transferred using 2 wires (DUAL) or 4 +-- +1.7.10.4 |