mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-21 08:46:49 +07:00
9a0d440427
This patch adds binding information for IBM/AMCC/APM GPIO Controllers of the PowerPC 4XX series and compatible SoCs. The "PowerPC 405EP Embedded Processor Data Sheet" has the following to say about the GPIO controllers: " - Controller functions and GPIO registers are programmed and accessed via memory-mapped OPB bus master accesses - All GPIOs are pin-shared with other functions. DCRs control whether a particular pin that has GPIO capabilities acts as a GPIO or is used for another purpose. - Each GPIO outputs is separately programmable to emulate an open-drain driver (i.e. drives to zero, threestated if output bit is 1) " The ppc4xx_gpio.c driver is part of the platform/sysdev drivers in arch/powerpc/sysdev. Signed-off-by: Christian Lamparter <chunkeey@googlemail.com> Signed-off-by: Rob Herring <robh@kernel.org>
25 lines
799 B
Plaintext
25 lines
799 B
Plaintext
* IBM/AMCC/APM GPIO Controller for PowerPC 4XX series and compatible SoCs
|
|
|
|
All GPIOs are pin-shared with other functions. DCRs control whether a
|
|
particular pin that has GPIO capabilities acts as a GPIO or is used for
|
|
another purpose. GPIO outputs are separately programmable to emulate
|
|
an open-drain driver.
|
|
|
|
Required properties:
|
|
- compatible: must be "ibm,ppc4xx-gpio"
|
|
- reg: address and length of the register set for the device
|
|
- #gpio-cells: must be set to 2. The first cell is the pin number
|
|
and the second cell is used to specify the gpio polarity:
|
|
0 = active high
|
|
1 = active low
|
|
- gpio-controller: marks the device node as a gpio controller.
|
|
|
|
Example:
|
|
|
|
GPIO0: gpio@ef600b00 {
|
|
compatible = "ibm,ppc4xx-gpio";
|
|
reg = <0xef600b00 0x00000048>;
|
|
#gpio-cells = <2>;
|
|
gpio-controller;
|
|
};
|