Re: [PATCH linux v5 1/2] Documentation: dt-bindings: Document bindings for ASPEED AST2400/AST2500 PWM and Fan tach controller device driver
From: Rob Herring <robh@kernel.org>
Date: 2017-03-30 22:46:20
Also in:
linux-hwmon, lkml, openbmc
On Fri, Mar 24, 2017 at 11:17:22AM -0700, Jaghathiswari Rankappagounder Natarajan wrote:
quoted hunk ↗ jump to hunk
This binding provides interface for adding values related to ASPEED AST2400/2500 PWM and Fan tach controller support. The PWM controller can support upto 8 PWM output ports. The Fan tach controller can support upto 16 tachometer inputs. Signed-off-by: Jaghathiswari Rankappagounder Natarajan <redacted> --- v5: - Changed the naming scheme to aspeed,ast2400/2500-pwm-tacho - Removed gpio pin muxing - Added aspeed vendor prefix for fan-tach-ch - Changed to fan@0/1 - Changed reg to 32 bits v4: - Used 'reg' v3: - Made the structure more common v2: - Removed '_' in node and property names - Gave some explanation for the properties used .../devicetree/bindings/hwmon/aspeed-pwm-tacho.txt | 68 ++++++++++++++++++++++ 1 file changed, 68 insertions(+) create mode 100644 Documentation/devicetree/bindings/hwmon/aspeed-pwm-tacho.txtdiff --git a/Documentation/devicetree/bindings/hwmon/aspeed-pwm-tacho.txt b/Documentation/devicetree/bindings/hwmon/aspeed-pwm-tacho.txt new file mode 100644 index 000000000000..f96d32bfcdfa --- /dev/null +++ b/Documentation/devicetree/bindings/hwmon/aspeed-pwm-tacho.txt@@ -0,0 +1,68 @@ +ASPEED AST2400/AST2500 PWM and Fan Tacho controller device driver + +The ASPEED PWM controller can support upto 8 PWM outputs. The ASPEED Fan Tacho +controller can support upto 16 Fan tachometer inputs. + +There can be upto 8 fans supported. Each fan can have one PWM output and +one/two Fan tach inputs. + +Required properties for pwm-tacho node: +- #address-cells : should be 1. + +- #size-cells : should be 1. + +- reg : address and length of the register set for the device. + +- pinctrl-names : a pinctrl state named "default" must be defined. + +- pinctrl-0 : phandle referencing pin configuration of the PWM ports. + +- compatible : should be "aspeed,ast2400-pwm-tacho" for AST2400 and + "aspeed,ast2500-pwm-tacho" for AST2500. + +- clocks : a fixed clock providing input clock frequency(PWM + and Fan Tach clock) + +fan subnode format: +=================== +Under fan subnode there can upto 8 child nodes, with each child node +representing a fan. If there are 8 fans each fan can have one PWM port and +one/two Fan tach inputs. + +Required properties for each child node: +- reg : should specify PWM source port. + integer value in the range 0 to 7 with 0 indicating PWM port A and + 7 indicating PWM port H. + +- aspeed-fan-tach-ch : should specify the Fan tach input channel.
aspeed,fan-tach-ch With that, Acked-by: Rob Herring <robh@kernel.org>
+ integer value in the range 0 through 15, with 0 indicating
+ Fan tach channel 0 and 15 indicating Fan tach channel 15.
+ Atleast one Fan tach input channel is required.
+
+Examples:
+
+pwm_tacho_fixed_clk: fixedclk {
+ compatible = "fixed-clock";
+ #clock-cells = <0>;
+ clock-frequency = <24000000>;
+}
+
+pwm_tacho: pwmtachocontroller@1e786000 {
+ #address-cells = <1>;
+ #size-cells = <1>;
+ reg = <0x1E786000 0x1000>;
+ compatible = "aspeed,ast2500-pwm-tacho";
+ clocks = <&pwm_tacho_fixed_clk>;
+ pinctrl-names = "default";
+ pinctrl-0 = <&pinctrl_pwm0_default &pinctrl_pwm1_default>;
+
+ fan@0 {
+ reg = <0x00>;
+ aspeed-fan-tach-ch = /bits/ 8 <0x00>;
+ };
+
+ fan@1 {
+ reg = <0x01>;
+ aspeed-fan-tach-ch = /bits/ 8 <0x01 0x02>;
+ };
+};
--
2.12.1.578.ge9c3154ca4-goog