From mboxrd@z Thu Jan 1 00:00:00 1970 From: Brian Norris Subject: Re: [PATCH v6] mwifiex: parse device tree node for PCIe Date: Wed, 26 Oct 2016 13:56:34 -0700 Message-ID: <20161026205634.GA13170@localhost> References: <1477070156-109965-1-git-send-email-rajatja@google.com> <1477084869-15612-1-git-send-email-rajatja@google.com> <20161026201735.GA10192@localhost> <20161026204648.GD3989@dtor-ws> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-wireless-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Rajat Jain Cc: Dmitry Torokhov , linux-wireless-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Xinming Hu , Amitkumar Karwar , Brian Norris , Kalle Valo , Rob Herring , Rajat Jain List-Id: devicetree@vger.kernel.org On Wed, Oct 26, 2016 at 01:51:48PM -0700, Rajat Jain wrote: > On Wed, Oct 26, 2016 at 1:46 PM, Dmitry Torokhov > wrote: > On Wed, Oct 26, 2016 at 01:17:36PM -0700, Brian Norris wrote: > Sorry, I just saw this... Why do we need devicetree data for > discoverable bus (PCI)? How does the driver work on systems that do not > use DT? Why do we need them to behave differently? > > There are a couple of out-of-band GPIO pins from Marvell chip that can > serve as wake-up pins (wake up the CPU when asserted). The Marvell chip > has to be told which GPIO pin is to be used as the wake-up pin. The pin to > be used is system / platform dependent. (On some systems it could be > GPIO13, on others it could be GPIO14 etc depending on how the marvell chip > is wired up to the CPU). There's also calibration data. See "marvell,caldata*" and "marvell,wakeup-pin" properties. Currently only for SDIO, in Documentation/devicetree/bindings/net/wireless/marvell-sd8xxx.txt, but we're adding support for PCIe. Brian