| Message ID | 1467882892-27589-2-git-send-email-peter.chen@nxp.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Am Donnerstag, den 07.07.2016, 17:14 +0800 schrieb Peter Chen: > Add binding doc for generic power sequence library. > > Signed-off-by: Peter Chen <peter.chen@nxp.com> > --- > .../bindings/power/pwrseq/pwrseq-generic.txt | 56 ++++++++++++++++++++++ > 1 file changed, 56 insertions(+) > create mode 100644 Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt > > diff --git a/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt b/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt > new file mode 100644 > index 0000000..4b23834 > --- /dev/null > +++ b/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt > @@ -0,0 +1,56 @@ > +The generic power sequence library > + > +Some hard-wired USB/MMC devices need to do power sequence to let the > +device work normally, the typical power sequence like: enable USB > +PHY clock, toggle reset pin, etc. But current Linux USB driver > +lacks of such code to do it, it may cause some hard-wired USB devices > +works abnormal or can't be recognized by controller at all. The > +power sequence will be done before this device can be found at USB > +bus. > + > +The power sequence properties is under the device node. > + > +Required properties: > +- power-sequence: this device needs to do power sequence before enumeration > + > +Optional properties: > +- clocks: the input clock for device. > +- clock-name: must be "pwrseq-clk" The "-clk" in the clock name is redundant. > +- pwrseq-reset-gpios: Should specify the GPIO for reset. > +- pwrseq-reset-duration-us: the duration in microsecond for assert reset signal. I understand you want to make it explicit that this GPIO is for the pwrseq library, but are we really gaining anything over just calling these reset-gpios and reset-duration-us? The same applies to the clock name above. > +Below is the example of USB power sequence properties on USB device > +nodes which have two level USB hubs. > + > +&usbotg1 { > + vbus-supply = <®_usb_otg1_vbus>; > + pinctrl-names = "default"; > + pinctrl-0 = <&pinctrl_usb_otg1_id>; > + status = "okay"; > + > + #address-cells = <1>; > + #size-cells = <0>; > + hub: genesys@1 { > + compatible = "usb5e3,608"; > + reg = <1>; > + > + power-sequence; > + clocks = <&clks IMX6SX_CLK_CKO>; > + clock-names = "pwrseq-clk"; > + pwrseq-reset-gpios = <&gpio4 5 GPIO_ACTIVE_LOW>; /* hub reset pin */ > + pwrseq-reset-duration-us = <10>; > + > + #address-cells = <1>; > + #size-cells = <0>; > + ethernet: asix@1 { > + compatible = "usbb95,1708"; > + reg = <1>; > + > + power-sequence; > + clocks = <&clks IMX6SX_CLK_IPG>; > + clock-names = "pwrseq-clk"; > + pwrseq-reset-gpios = <&gpio4 6 GPIO_ACTIVE_LOW>; /* ethernet_rst */ > + pwrseq-reset-duration-us = <15>; > + }; This looks weird. The hub and ethernet chips don't have "pwrseq" clock and reset input pins. I'd remove the clock-names and pwrseq- reset prefix. regards Philipp
On 07/07/2016 02:47 AM, Philipp Zabel wrote: > Am Donnerstag, den 07.07.2016, 17:14 +0800 schrieb Peter Chen: >> Add binding doc for generic power sequence library. >> >> Signed-off-by: Peter Chen <peter.chen@nxp.com> >> --- >> .../bindings/power/pwrseq/pwrseq-generic.txt | 56 ++++++++++++++++++++++ >> 1 file changed, 56 insertions(+) >> create mode 100644 Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt >> >> diff --git a/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt b/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt >> new file mode 100644 >> index 0000000..4b23834 >> --- /dev/null >> +++ b/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt >> @@ -0,0 +1,56 @@ >> +The generic power sequence library >> + >> +Some hard-wired USB/MMC devices need to do power sequence to let the >> +device work normally, the typical power sequence like: enable USB >> +PHY clock, toggle reset pin, etc. But current Linux USB driver >> +lacks of such code to do it, it may cause some hard-wired USB devices >> +works abnormal or can't be recognized by controller at all. The >> +power sequence will be done before this device can be found at USB >> +bus. >> + >> +The power sequence properties is under the device node. >> + >> +Required properties: >> +- power-sequence: this device needs to do power sequence before enumeration >> + >> +Optional properties: >> +- clocks: the input clock for device. >> +- clock-name: must be "pwrseq-clk" > The "-clk" in the clock name is redundant. > >> +- pwrseq-reset-gpios: Should specify the GPIO for reset. >> +- pwrseq-reset-duration-us: the duration in microsecond for assert reset signal. > I understand you want to make it explicit that this GPIO is for the > pwrseq library, but are we really gaining anything over just calling > these reset-gpios and reset-duration-us? > The same applies to the clock name above. using reset-gpios makes sense to me too. The above "power-sequence" might then be better called "reset-on-init", But really, if a device has a reset gpio shouldn't the default behavior be to reset it on boot and when coming back from sleep? Is a special property even needed? > >> +Below is the example of USB power sequence properties on USB device >> +nodes which have two level USB hubs. >> + >> +&usbotg1 { >> + vbus-supply = <®_usb_otg1_vbus>; >> + pinctrl-names = "default"; >> + pinctrl-0 = <&pinctrl_usb_otg1_id>; >> + status = "okay"; >> + >> + #address-cells = <1>; >> + #size-cells = <0>; >> + hub: genesys@1 { >> + compatible = "usb5e3,608"; >> + reg = <1>; >> + >> + power-sequence; >> + clocks = <&clks IMX6SX_CLK_CKO>; >> + clock-names = "pwrseq-clk"; >> + pwrseq-reset-gpios = <&gpio4 5 GPIO_ACTIVE_LOW>; /* hub reset pin */ >> + pwrseq-reset-duration-us = <10>; >> + >> + #address-cells = <1>; >> + #size-cells = <0>; >> + ethernet: asix@1 { >> + compatible = "usbb95,1708"; >> + reg = <1>; >> + >> + power-sequence; >> + clocks = <&clks IMX6SX_CLK_IPG>; >> + clock-names = "pwrseq-clk"; >> + pwrseq-reset-gpios = <&gpio4 6 GPIO_ACTIVE_LOW>; /* ethernet_rst */ >> + pwrseq-reset-duration-us = <15>; >> + }; > This looks weird. The hub and ethernet chips don't have "pwrseq" clock > and reset input pins. I'd remove the clock-names and pwrseq- reset > prefix. > > regards > Philipp > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
On Thu, Jul 07, 2016 at 11:47:14AM +0200, Philipp Zabel wrote: > Am Donnerstag, den 07.07.2016, 17:14 +0800 schrieb Peter Chen: > > Add binding doc for generic power sequence library. > > > > Signed-off-by: Peter Chen <peter.chen@nxp.com> > > --- > > .../bindings/power/pwrseq/pwrseq-generic.txt | 56 ++++++++++++++++++++++ > > 1 file changed, 56 insertions(+) > > create mode 100644 Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt > > > > diff --git a/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt b/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt > > new file mode 100644 > > index 0000000..4b23834 > > --- /dev/null > > +++ b/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt > > @@ -0,0 +1,56 @@ > > +The generic power sequence library > > + > > +Some hard-wired USB/MMC devices need to do power sequence to let the > > +device work normally, the typical power sequence like: enable USB > > +PHY clock, toggle reset pin, etc. But current Linux USB driver > > +lacks of such code to do it, it may cause some hard-wired USB devices > > +works abnormal or can't be recognized by controller at all. The > > +power sequence will be done before this device can be found at USB > > +bus. > > + > > +The power sequence properties is under the device node. > > + > > +Required properties: > > +- power-sequence: this device needs to do power sequence before enumeration > > + > > +Optional properties: > > +- clocks: the input clock for device. > > +- clock-name: must be "pwrseq-clk" > > The "-clk" in the clock name is redundant. > > > +- pwrseq-reset-gpios: Should specify the GPIO for reset. > > +- pwrseq-reset-duration-us: the duration in microsecond for assert reset signal. > > I understand you want to make it explicit that this GPIO is for the > pwrseq library, but are we really gaining anything over just calling > these reset-gpios and reset-duration-us? > The same applies to the clock name above. > > > +Below is the example of USB power sequence properties on USB device > > +nodes which have two level USB hubs. > > + > > +&usbotg1 { > > + vbus-supply = <®_usb_otg1_vbus>; > > + pinctrl-names = "default"; > > + pinctrl-0 = <&pinctrl_usb_otg1_id>; > > + status = "okay"; > > + > > + #address-cells = <1>; > > + #size-cells = <0>; > > + hub: genesys@1 { > > + compatible = "usb5e3,608"; > > + reg = <1>; > > + > > + power-sequence; > > + clocks = <&clks IMX6SX_CLK_CKO>; > > + clock-names = "pwrseq-clk"; > > + pwrseq-reset-gpios = <&gpio4 5 GPIO_ACTIVE_LOW>; /* hub reset pin */ > > + pwrseq-reset-duration-us = <10>; > > + > > + #address-cells = <1>; > > + #size-cells = <0>; > > + ethernet: asix@1 { > > + compatible = "usbb95,1708"; > > + reg = <1>; > > + > > + power-sequence; > > + clocks = <&clks IMX6SX_CLK_IPG>; > > + clock-names = "pwrseq-clk"; > > + pwrseq-reset-gpios = <&gpio4 6 GPIO_ACTIVE_LOW>; /* ethernet_rst */ > > + pwrseq-reset-duration-us = <15>; > > + }; > > This looks weird. The hub and ethernet chips don't have "pwrseq" clock > and reset input pins. I'd remove the clock-names and pwrseq- reset > prefix. > I agree with you, and will keep property name like last version [1].
On Thu, Jul 07, 2016 at 04:53:07PM -0700, Joshua Clayton wrote: > > > On 07/07/2016 02:47 AM, Philipp Zabel wrote: > > Am Donnerstag, den 07.07.2016, 17:14 +0800 schrieb Peter Chen: > >> Add binding doc for generic power sequence library. > >> > >> Signed-off-by: Peter Chen <peter.chen@nxp.com> > >> --- > >> .../bindings/power/pwrseq/pwrseq-generic.txt | 56 ++++++++++++++++++++++ > >> 1 file changed, 56 insertions(+) > >> create mode 100644 Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt > >> > >> diff --git a/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt b/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt > >> new file mode 100644 > >> index 0000000..4b23834 > >> --- /dev/null > >> +++ b/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt > >> @@ -0,0 +1,56 @@ > >> +The generic power sequence library > >> + > >> +Some hard-wired USB/MMC devices need to do power sequence to let the > >> +device work normally, the typical power sequence like: enable USB > >> +PHY clock, toggle reset pin, etc. But current Linux USB driver > >> +lacks of such code to do it, it may cause some hard-wired USB devices > >> +works abnormal or can't be recognized by controller at all. The > >> +power sequence will be done before this device can be found at USB > >> +bus. > >> + > >> +The power sequence properties is under the device node. > >> + > >> +Required properties: > >> +- power-sequence: this device needs to do power sequence before enumeration > >> + > >> +Optional properties: > >> +- clocks: the input clock for device. > >> +- clock-name: must be "pwrseq-clk" > > The "-clk" in the clock name is redundant. > > > >> +- pwrseq-reset-gpios: Should specify the GPIO for reset. > >> +- pwrseq-reset-duration-us: the duration in microsecond for assert reset signal. > > I understand you want to make it explicit that this GPIO is for the > > pwrseq library, but are we really gaining anything over just calling > > these reset-gpios and reset-duration-us? > > The same applies to the clock name above. > using reset-gpios makes sense to me too. > The above "power-sequence" might then be better called "reset-on-init", > But really, if a device has a reset gpio shouldn't the default behavior be to > reset it on boot and when coming back from sleep? > Is a special property even needed? The power sequence does not include reset process only, it may include clock and power as well.
diff --git a/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt b/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt new file mode 100644 index 0000000..4b23834 --- /dev/null +++ b/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt @@ -0,0 +1,56 @@ +The generic power sequence library + +Some hard-wired USB/MMC devices need to do power sequence to let the +device work normally, the typical power sequence like: enable USB +PHY clock, toggle reset pin, etc. But current Linux USB driver +lacks of such code to do it, it may cause some hard-wired USB devices +works abnormal or can't be recognized by controller at all. The +power sequence will be done before this device can be found at USB +bus. + +The power sequence properties is under the device node. + +Required properties: +- power-sequence: this device needs to do power sequence before enumeration + +Optional properties: +- clocks: the input clock for device. +- clock-name: must be "pwrseq-clk" +- pwrseq-reset-gpios: Should specify the GPIO for reset. +- pwrseq-reset-duration-us: the duration in microsecond for assert reset signal. + +Below is the example of USB power sequence properties on USB device +nodes which have two level USB hubs. + +&usbotg1 { + vbus-supply = <®_usb_otg1_vbus>; + pinctrl-names = "default"; + pinctrl-0 = <&pinctrl_usb_otg1_id>; + status = "okay"; + + #address-cells = <1>; + #size-cells = <0>; + hub: genesys@1 { + compatible = "usb5e3,608"; + reg = <1>; + + power-sequence; + clocks = <&clks IMX6SX_CLK_CKO>; + clock-names = "pwrseq-clk"; + pwrseq-reset-gpios = <&gpio4 5 GPIO_ACTIVE_LOW>; /* hub reset pin */ + pwrseq-reset-duration-us = <10>; + + #address-cells = <1>; + #size-cells = <0>; + ethernet: asix@1 { + compatible = "usbb95,1708"; + reg = <1>; + + power-sequence; + clocks = <&clks IMX6SX_CLK_IPG>; + clock-names = "pwrseq-clk"; + pwrseq-reset-gpios = <&gpio4 6 GPIO_ACTIVE_LOW>; /* ethernet_rst */ + pwrseq-reset-duration-us = <15>; + }; + }; +};
Add binding doc for generic power sequence library. Signed-off-by: Peter Chen <peter.chen@nxp.com> --- .../bindings/power/pwrseq/pwrseq-generic.txt | 56 ++++++++++++++++++++++ 1 file changed, 56 insertions(+) create mode 100644 Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt