Re: [PATCH linux v1 1/2] Documentation: dt-bindings: Document bindings for ASPEED AST2400/AST2500 pwm and fan tach controller device driver
On Fri, Jan 27, 2017 at 1:32 AM, Jaghathiswari Rankappagounder Natarajan wrote: > > > On Fri, Jan 13, 2017 at 8:21 AM, Rob Herring wrote: >> >> On Mon, Jan 09, 2017 at 01:59:34PM -0800, Jaghathiswari Rankappagounder >> Natarajan wrote: >> > 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. >> > PWM clock types M, N and 0 are three types just to have three >> > independent >> > PWM sources. >> > >> > Signed-off-by: Jaghathiswari Rankappagounder Natarajan >> > >> > --- >> > .../devicetree/bindings/hwmon/aspeed-pwm-tacho.txt | 153 >> > + >> >> Perhaps bindings/pwm/... even though this is more than just PWM. > > The corresponding hwmon driver is present in /drivers/hwmon/. So would it > make more > > sense to include the devicetree document for that driver in > /devicetree/bindings/hwmon/. > > In future if there any more hwmon related functionalities are added to this > driver then /devicetree/bindings/hwmon/ would be more relevant. > > >> >> >> > 1 file changed, 153 insertions(+) >> > create mode 100644 >> > Documentation/devicetree/bindings/hwmon/aspeed-pwm-tacho.txt >> > >> > diff --git >> > a/Documentation/devicetree/bindings/hwmon/aspeed-pwm-tacho.txt >> > b/Documentation/devicetree/bindings/hwmon/aspeed-pwm-tacho.txt >> > new file mode 100644 >> > index ..8f346409ee8c >> > --- /dev/null >> > +++ b/Documentation/devicetree/bindings/hwmon/aspeed-pwm-tacho.txt >> > @@ -0,0 +1,153 @@ >> > +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 tachometer inputs. The PWM controller >> > supports >> > +3 types of frequency mode PWM for fan speed control. PWM clock types M, >> > N and 0 >> > +are 3 types of frequency mode PWM just to have 3 independent PWM >> > sources. >> > + >> > +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 >> > AST2400/AST2500 PWM >> > + ports. >> > + >> > +- compatible : should be "aspeed,aspeed2400-pwm-tacho" for AST2400 or >> > +"aspeed,aspeed2500-pwm-tacho" for AST2500. >> > + >> > +- clocks : a fixed clock providing input clock frequency(PWM >> > +and Fan Tach clock) >> > + >> > +type_values subnode format: >> >> Don't use '_' in node or property names. > > Done. >> >> >> > +=== >> > +Under type_values subnode there can be upto 3 child nodes indicating >> > type M/N/O >> > +values. Atleast one child node is required. >> > + >> > +Required properties for the child node(type M/N/O): >> > +- pwm_period : indicates type M/N/O PWM period, as per the >> > AST2400/AST2500 >> > +datasheet. integer value in the range 0 to 255. >> >> >> > + >> > +- pwm_clock_division_l : indicates type M/N/O PWM clock division L >> > value, >> > + as per the AST2400/AST2500 datasheet. >> > + integer value in the range 0 to 15. >> > + 0 here indicates divide 1, 1 indicates divide 2, >> > + 2 indicates divide 4, 3 indicates divide 6, and >> > so on >> > + till 15 indicates divide 30. >> > + >> > +- pwm_clock_division_h : indicates type M/N/O PWM clock division H >> > value, >> > + as per the AST2400/AST2500 datasheet. >> > + integer value in the range 0 to 15. >> > + 0 here indicates divide 1, 1 indicates divide 2, >> > + 2 indicates divide 4, 3 indicates divide 8, and >> > so on >> > + till 15 indicates divide 32768. >> >> Can't you have a single divider value and driver convert to register >> values? Really, you should specify the PWM period in ns/us and calculate >> the divider based on the input clock freq. (i.e. use the clock binding). >> There's already PWM binding to specify the period. >> >> I think you should have a node for the fan using the PWM binding and >> perhaps moving some of these properties to the fan node. > > > There are three different types M, N, O. These three types are just to have > > different PWM/Fan Tach settings. Each type can have the following settings: > > PWM related: > > 1) PWM period > > 2) PWM clock division high > > 3) PWM clock division low > > Fan Tach related: > > 1) Fan Tach type enable > > 2) Fan Tach clock division > > 3) Fan Tach mode selecti
Re: [PATCH linux v1 1/2] Documentation: dt-bindings: Document bindings for ASPEED AST2400/AST2500 pwm and fan tach controller device driver
On Mon, Jan 09, 2017 at 01:59:34PM -0800, Jaghathiswari Rankappagounder Natarajan wrote: > 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. > PWM clock types M, N and 0 are three types just to have three independent > PWM sources. > > Signed-off-by: Jaghathiswari Rankappagounder Natarajan > --- > .../devicetree/bindings/hwmon/aspeed-pwm-tacho.txt | 153 > + Perhaps bindings/pwm/... even though this is more than just PWM. > 1 file changed, 153 insertions(+) > create mode 100644 > Documentation/devicetree/bindings/hwmon/aspeed-pwm-tacho.txt > > diff --git a/Documentation/devicetree/bindings/hwmon/aspeed-pwm-tacho.txt > b/Documentation/devicetree/bindings/hwmon/aspeed-pwm-tacho.txt > new file mode 100644 > index ..8f346409ee8c > --- /dev/null > +++ b/Documentation/devicetree/bindings/hwmon/aspeed-pwm-tacho.txt > @@ -0,0 +1,153 @@ > +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 tachometer inputs. The PWM controller supports > +3 types of frequency mode PWM for fan speed control. PWM clock types M, N > and 0 > +are 3 types of frequency mode PWM just to have 3 independent PWM sources. > + > +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 AST2400/AST2500 > PWM > + ports. > + > +- compatible : should be "aspeed,aspeed2400-pwm-tacho" for AST2400 or > +"aspeed,aspeed2500-pwm-tacho" for AST2500. > + > +- clocks : a fixed clock providing input clock frequency(PWM > +and Fan Tach clock) > + > +type_values subnode format: Don't use '_' in node or property names. > +=== > +Under type_values subnode there can be upto 3 child nodes indicating type > M/N/O > +values. Atleast one child node is required. > + > +Required properties for the child node(type M/N/O): > +- pwm_period : indicates type M/N/O PWM period, as per the AST2400/AST2500 > +datasheet. integer value in the range 0 to 255. > + > +- pwm_clock_division_l : indicates type M/N/O PWM clock division L value, > + as per the AST2400/AST2500 datasheet. > + integer value in the range 0 to 15. > + 0 here indicates divide 1, 1 indicates divide 2, > + 2 indicates divide 4, 3 indicates divide 6, and so on > + till 15 indicates divide 30. > + > +- pwm_clock_division_h : indicates type M/N/O PWM clock division H value, > + as per the AST2400/AST2500 datasheet. > + integer value in the range 0 to 15. > + 0 here indicates divide 1, 1 indicates divide 2, > + 2 indicates divide 4, 3 indicates divide 8, and so on > + till 15 indicates divide 32768. Can't you have a single divider value and driver convert to register values? Really, you should specify the PWM period in ns/us and calculate the divider based on the input clock freq. (i.e. use the clock binding). There's already PWM binding to specify the period. I think you should have a node for the fan using the PWM binding and perhaps moving some of these properties to the fan node. > + > +- fan_tach_enable : indicates fan tach enable of type M/N/O as per the > + AST2400/AST2500 datasheet. boolean value. > + > +- fan_tach_clock_division : indicates fan tach clock division as per the > + AST2400/AST2500 datasheet. > + integer value in the range 0 to 7. > + 0 indicates divide 4, 1 indicates divide 16, > + 2 indicates divide 64, 3 indicates divide 256 > + and so on till 7 indicates divide 65536. > + > +- fan_tach_mode_selection : indicates fan tach mode mode selection as per the > + AST2400/AST2500 datasheet. integer value in the > + range 0 to 2. 0 indicates falling edge, 1 indicates > + rising edge and 2 indicates both edges. > + > +- fan_tach_period : indicates fan tach period as per the AST2400/AST2500 > + datasheet. integer value (can be upto 16 bits long). > + > +pwm_port subnode format: > + > +Under pwm_port subnode there can upto 8 child nodes each indicating values > +for one of the 8 PWM output ports. > + > +Required properties for each child node(starti
