From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rob Herring Subject: Re: [PATCH 2/4] doc: dt-binding: ci-hdrc-usb2: add i.mx specific binding "need-three-clocks" Date: Wed, 16 Sep 2015 08:54:25 -0500 Message-ID: <55F97491.5060105@kernel.org> References: <1442368183-8103-1-git-send-email-peter.chen@freescale.com> <1442368183-8103-2-git-send-email-peter.chen@freescale.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1442368183-8103-2-git-send-email-peter.chen-KZfg59tc24xl57MIdRCFDg@public.gmane.org> Sender: linux-usb-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Peter Chen Cc: shawn.guo-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org, linux-usb-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, kernel-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org, fabio.estevam-KZfg59tc24xl57MIdRCFDg@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, pawel.moll-5wv7dgnIgG8@public.gmane.org, mark.rutland-5wv7dgnIgG8@public.gmane.org List-Id: devicetree@vger.kernel.org On 09/15/2015 08:49 PM, Peter Chen wrote: > Some SoCs needs three clock to let controller work, but others only > need one, add one property to differentiate this. A given licensed IP block is going to have the same number of clock inputs from SOC to SOC. So different numbers of clocks is a bit suspect. I guess there can be variations in bus clocks or other outside logic. > > Signed-off-by: Peter Chen > --- > Documentation/devicetree/bindings/usb/ci-hdrc-usb2.txt | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/Documentation/devicetree/bindings/usb/ci-hdrc-usb2.txt b/Documentation/devicetree/bindings/usb/ci-hdrc-usb2.txt > index f15a317..4900092 100644 > --- a/Documentation/devicetree/bindings/usb/ci-hdrc-usb2.txt > +++ b/Documentation/devicetree/bindings/usb/ci-hdrc-usb2.txt > @@ -54,6 +54,9 @@ i.mx specific properties > argument that indicate usb controller index > - disable-over-current: disable over current detect > - external-vbus-divider: enables off-chip resistor divider for Vbus > +- need-three-clocks: the SoC before imx6 series (except for imx23/imx28) > + needs three clcoks for controller, others only need one. Without this > + property, the driver will consider this controller only need one clock. That's pretty ugly and unnecessary. Either use the compatible string to determine if you have 3 clocks or just always try to retrieve the 3 clocks in the driver and fall back to 1. Rob -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html