From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mika Westerberg Subject: Re: [PATCH V2] i2c-designware: Add Intel Baytrail PMIC I2C bus support Date: Tue, 11 Nov 2014 13:50:28 +0200 Message-ID: <20141111115028.GH1454@lahna.fi.intel.com> References: <1410543367-6565-1-git-send-email-david.e.box@linux.intel.com> <1411497626-7984-1-git-send-email-david.e.box@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1411497626-7984-1-git-send-email-david.e.box-VuQAYsv1563Yd54FQh9/CA@public.gmane.org> Sender: linux-i2c-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: "David E. Box" Cc: wsa-z923LK4zBo2bacvFa/9K2g@public.gmane.org, jdelvare-l3A5Bk7waGM@public.gmane.org, arnd-r2nGTMty4D4@public.gmane.org, maxime.ripard-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org, dianders-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org, u.kleine-koenig-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org, laurent.pinchart+renesas-ryLnwIuWjnjg/C1BVhZhaw@public.gmane.org, boris.brezillon-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org, maxime.coquelin-qxv4g6HH51o@public.gmane.org, andrew-g2DYL2Zd6BY@public.gmane.org, sjg-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org, markus.mayer-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org, ch.naveen-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org, jacob.jun.pan-VuQAYsv1563Yd54FQh9/CA@public.gmane.org, max.schwarz-BGeptl67XyCzQB+pC5nmwQ@public.gmane.org, skuribay-e+AXbWqSrlAAvxtiuMwx3w@public.gmane.org, Romain.Baeriswyl-ux6zf3SgZrrQT0dZR+AlfA@public.gmane.org, wenkai.du-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org, chiau.ee.chew-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org, christian.ruppert-ux6zf3SgZrrQT0dZR+AlfA@public.gmane.org, alan-VuQAYsv1563Yd54FQh9/CA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-i2c@vger.kernel.org On Tue, Sep 23, 2014 at 11:40:26AM -0700, David E. Box wrote: > +void baytrail_evaluate_sem(struct dw_i2c_dev *dev) > +{ > + acpi_status status; > + unsigned long long shared_host = 0; > + acpi_handle handle; > + > + if (!dev || !dev->dev) { > + pr_err("%s:%d: device is NULL\n", __func__, __LINE__); Not sure if it is useful to print things like above. > + return; > + } > + > + handle = ACPI_HANDLE(dev->dev); > + if (!handle) > + return; > + > + status = acpi_evaluate_integer(handle, "_SEM", NULL, &shared_host); Maybe it is better to check first if the operation succeeded before touching shared_host? if (ACPI_SUCCESS(status) && shared_host) { } Otherwise ACPI parts look good to me. > + > + if (shared_host) { > + dev_info(dev->dev, "I2C bus managed by PUNIT\n"); > + dev->has_hw_lock = true; > + dev->pm_runtime_disabled = true; > + } > +} > +EXPORT_SYMBOL(baytrail_evaluate_sem);