From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pandy Gao Subject: RE: [Patch V1 2/2] spi: fsl-lpspi: add VLLS mode support Date: Wed, 18 Jan 2017 03:50:16 +0000 Message-ID: References: <1483522697-6691-1-git-send-email-pandy.gao@nxp.com> <1483522697-6691-2-git-send-email-pandy.gao@nxp.com> <20170109193350.aufenjuhtge5e3lu@sirena.org.uk> <20170117190407.p5ad3dz7ixqm4vz6@sirena.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Cc: "linux-spi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" To: Mark Brown Return-path: In-Reply-To: <20170117190407.p5ad3dz7ixqm4vz6-GFdadSzt00ze9xe1eoZjHA@public.gmane.org> Content-Language: en-US Sender: linux-spi-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: From: Mark Brown Sent: Wednesday, January 18, 2= 017 3:04 AM > To: Pandy Gao > Cc: linux-spi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org > Subject: Re: [Patch V1 2/2] spi: fsl-lpspi: add VLLS mode support >=20 > On Tue, Jan 17, 2017 at 07:03:28AM +0000, Pandy Gao wrote: >=20 > > > > The patch recovers the pinctrl setting when exit VLLS mode. >=20 > > > Why is this a change here and not in the pinctrl driver? It sounds > > > like it's the pinctrl driver that's forgetting the settings and > > > should be restoring them on resume but perhaps I'm missing > something here. >=20 > > If the pinctrl driver restores the setting on resume, then all device > > node should be scanned, which is irregular. >=20 > What would restoring the configuration have to do with scanning the > device tree? The changelog says this is just reapplying the same > settings we started out with so it's just a case of restoring the state o= f > the device after a runtime resume which is a perfectly normal thing for > a driver to do. We can reapply the initial settings as the configurations defined in device node iomuxc in pinctrl driver. However, I think there are some limitations. For example, conflicts may exist between enet1grp and ecspi3grp, which is not easy for the pinctrl driver to find out. &iomuxc { pinctrl_ecspi3: ecspi3grp=20 { ... }; pinctrl_enet1: enet1grp { ... }; } Best Regards Gao Pan -- To unsubscribe from this list: send the line "unsubscribe linux-spi" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html