On Fri, Jun 03, 2016 at 02:35:08PM +0200, Krzysztof Kozlowski wrote: > On 06/03/2016 04:02 AM, Rob Herring wrote: > > On Wed, Jun 01, 2016 at 10:02:15AM +0200, Krzysztof Kozlowski wrote: > >> Some devices need real hard-reset by cutting the power. During power > >> sequence turn off and on the regulator, if it is provided. > >> > >> Additionally add support for instantiating the pwrseq-simple device on a > >> generic property 'power-sequence'. The device will attach itself to the > >> node containing the property and parse the node's properties like > >> reset-gpios, ext-supply etc. > >> > >> Signed-off-by: Krzysztof Kozlowski <k.kozlowski@xxxxxxxxxxx> > >> --- > >> .../bindings/power/pwrseq/pwrseq-simple.txt | 29 +++++++- > >> drivers/power/pwrseq/pwrseq_simple.c | 85 +++++++++++++++++++++- > >> 2 files changed, 107 insertions(+), 7 deletions(-) > >> > >> diff --git a/Documentation/devicetree/bindings/power/pwrseq/pwrseq-simple.txt b/Documentation/devicetree/bindings/power/pwrseq/pwrseq-simple.txt > >> index ce0e76749671..a8c3f13ee83f 100644 > >> --- a/Documentation/devicetree/bindings/power/pwrseq/pwrseq-simple.txt > >> +++ b/Documentation/devicetree/bindings/power/pwrseq/pwrseq-simple.txt > >> @@ -1,11 +1,17 @@ > >> -* The simple MMC power sequence provider > >> +* The simple power sequence provider > >> > >> -The purpose of the simple MMC power sequence provider is to supports a set of > >> +The purpose of the simple power sequence provider is to supports a set of > >> common properties between various SOC designs. It thus enables us to use the > >> same provider for several SOC designs. > >> > >> -Required properties: > >> -- compatible : contains "mmc-pwrseq-simple". > >> +The driver supports two types of bindings: > >> +1. Separate node > >> + Required properties: > >> + - compatible : contains "mmc-pwrseq-simple". > > > > Please note that this is not recommended for new users. > > Sure. > > > > >> + > >> +2. Property for any node > >> + Required properties: > >> + - power-sequence > >> > >> Optional properties: > >> - reset-gpios : contains a list of GPIO specifiers. The reset GPIOs are asserted > >> @@ -16,6 +22,7 @@ Optional properties: > >> See ../clocks/clock-bindings.txt for details. > >> - clock-names : Must include the following entry: > >> "ext_clock" (External clock provided to the card). > >> +- ext-supply : External regulator supply > > > > What happens when there are 2 supplies? > > > > I'd prefer the name not be genericish and use the real supply names. > > Then the power seq code should just turn on all supplies it finds. If > > the order or timing to turn on matters, then sorry, no generic sequence. > > Understood. I'll change the code to use any supply. > > As for the genericness of this approach, Sylwester Nawrocki pointed an > old thread: > [PATCH v6 0/4] Runtime Interpreted Power Sequences > https://lkml.org/lkml/2012/9/12/127 > > How do you like that approach? > Rob, I am trying to implement the dts layout you suggested (see below), but I find it is very hard to it due to the device is still not created, without device, it is hard to manage the resources under this device ( Eg, de-initialization for probe deferral case). So, a common driver is suitable for this power sequence case. &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>; reset-gpios = <&gpio4 5 GPIO_ACTIVE_LOW>; /* hub reset pin */ reset-duration-us = <10>; clocks = <&clks IMX6SX_CLK_CKO>; }; }; -- Best Regards, Peter Chen -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
