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authorDavid Brown <davidb@codeaurora.org>2011-03-16 22:13:16 -0700
committerDavid Brown <davidb@codeaurora.org>2011-03-16 22:13:16 -0700
commit92c260f755c42337c550d8ac1f8ccd1b32bffb20 (patch)
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parent05e34754518b6a90d5c392790c032575fab12d66 (diff)
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Merge remote branch 'rmk/for-linus' into for-linus
* rmk/for-linus: (1557 commits) ARM: 6806/1: irq: introduce entry and exit functions for chained handlers ARM: 6781/1: Thumb-2: Work around buggy Thumb-2 short branch relocations in gas ARM: 6747/1: P2V: Thumb2 support ARM: 6798/1: aout-core: zero thread debug registers in a.out core dump ARM: 6796/1: Footbridge: Fix I/O mappings for NOMMU mode ARM: 6784/1: errata: no automatic Store Buffer drain on Cortex-A9 ARM: 6772/1: errata: possible fault MMU translations following an ASID switch ARM: 6776/1: mach-ux500: activate fix for errata 753970 ARM: 6794/1: SPEAr: Append UL to device address macros. ARM: 6793/1: SPEAr: Remove unused *_SIZE macros from spear*.h files ARM: 6792/1: SPEAr: Replace SIZE macro's with SZ_4K macros ARM: 6791/1: SPEAr3xx: Declare device structures after shirq code ARM: 6790/1: SPEAr: Clock Framework: Rename usbd clock and align apb_clk entry ARM: 6789/1: SPEAr3xx: Rename sdio to sdhci ARM: 6788/1: SPEAr: Include mach/hardware.h instead of mach/spear.h ARM: 6787/1: SPEAr: Reorder #includes in .h & .c files. ARM: 6681/1: SPEAr: add debugfs support to clk API ARM: 6703/1: SPEAr: update clk API support ARM: 6679/1: SPEAr: make clk API functions more generic ARM: 6737/1: SPEAr: formalized timer support ... Conflicts: arch/arm/mach-msm/board-msm7x27.c arch/arm/mach-msm/board-msm7x30.c arch/arm/mach-msm/board-qsd8x50.c arch/arm/mach-msm/board-sapphire.c arch/arm/mach-msm/include/mach/memory.h
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+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.
+
+The SPI master node requires the following 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.
+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
+assigning chip select numbers. Since SPI chip select configuration is
+flexible and non-standardized, it is left out of this binding with the
+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.
+
+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 example for an MPC5200 SPI bus:
+ spi@f00 {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ compatible = "fsl,mpc5200b-spi","fsl,mpc5200-spi";
+ reg = <0xf00 0x20>;
+ interrupts = <2 13 0 2 14 0>;
+ interrupt-parent = <&mpc5200_pic>;
+
+ ethernet-switch@0 {
+ compatible = "micrel,ks8995m";
+ spi-max-frequency = <1000000>;
+ reg = <0>;
+ };
+
+ codec@1 {
+ compatible = "ti,tlv320aic26";
+ spi-max-frequency = <100000>;
+ reg = <1>;
+ };
+ };