diff options
author | Tom Rini <trini@konsulko.com> | 2018-08-01 09:26:15 -0400 |
---|---|---|
committer | Tom Rini <trini@konsulko.com> | 2018-08-01 09:26:15 -0400 |
commit | 61523dde17d1539b8ea361e25909acfdfc465155 (patch) | |
tree | 03e544bf27cadc6d62f91e2c29c80ddfc3dff660 /doc/device-tree-bindings/gpio/snps,creg-gpio.txt | |
parent | 20a619c61775d99aaed07cf69ce449de054358a4 (diff) | |
parent | 8f590063ba635264303b1713c421df331743fd46 (diff) |
Merge tag 'arc-updates-for-2018.09-rc2' of git://git.denx.de/u-boot-arc
That's a set of prety minor changes and fixes for ARC.
Among them:
* Improvement in CREG GPIO driver used on ARC dev boards
that allow us to re-use the driver for SPI's chip select
* Enable SPI-flsh on AXS10x boards which allows to update
U-Boot binary that gets loaded by boot-ROM
* Fix accommodating always utilized unaligned access by
GCC for ARC starting from 8.1.0
Diffstat (limited to 'doc/device-tree-bindings/gpio/snps,creg-gpio.txt')
-rw-r--r-- | doc/device-tree-bindings/gpio/snps,creg-gpio.txt | 43 |
1 files changed, 43 insertions, 0 deletions
diff --git a/doc/device-tree-bindings/gpio/snps,creg-gpio.txt b/doc/device-tree-bindings/gpio/snps,creg-gpio.txt new file mode 100644 index 0000000000..46ceb65c53 --- /dev/null +++ b/doc/device-tree-bindings/gpio/snps,creg-gpio.txt @@ -0,0 +1,43 @@ +GPIO via CREG (control registers) driver + +31 9 7 5 0 < bit number +| | | | | +[ not used | gpio-1 | gpio-0 | <-shift-> ] < 32 bit register + ^ ^ + | | + write 0x2 == set output to "1" (activate) + write 0x3 == set output to "0" (deactivate) + +Required properties: +- compatible : "snps,creg-gpio" +- reg : Exactly one register range with length 0x4. +- #gpio-cells : Should be one - the pin number. +- gpio-controller : Marks the device node as a GPIO controller. +- gpio-count: Number of GPIO pins. +- gpio-bit-per-line: Number of bits per gpio line (see picture). +- gpio-first-shift: Shift (in bits) of the first GPIO field in register + (see picture). +- gpio-activate-val: Value should be set in corresponding field to set + output to "1" (see picture). Applied to all GPIO ports. +- gpio-deactivate-val: Value should be set in corresponding field to set + output to "0" (see picture). Applied to all GPIO ports. + +Optional properties: +- gpio-bank-name: name of bank (as default driver name is used is used) +- gpio-default-val: array of default output values (must me 0 or 1) + +Example (see picture): + +gpio: gpio@f00014b0 { + compatible = "snps,creg-gpio"; + reg = <0xf00014b0 0x4>; + gpio-controller; + #gpio-cells = <1>; + gpio-bank-name = "hsdk-spi-cs"; + gpio-count = <2>; + gpio-first-shift = <5>; + gpio-bit-per-line = <2>; + gpio-activate-val = <2>; + gpio-deactivate-val = <3>; + gpio-default-val = <1 1>; +}; |