From mboxrd@z Thu Jan 1 00:00:00 1970 From: marex@denx.de (Marek Vasut) Date: Sun, 28 Oct 2012 23:48:48 +0100 Subject: [PATCH v2 1/5] ARM: PXA: Add z2-usb-switch driver In-Reply-To: References: <201210282338.03505.marex@denx.de> Message-ID: <201210282348.48681.marex@denx.de> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Dear Vasily Khoruzhick, > On Mon, Oct 29, 2012 at 1:38 AM, Marek Vasut wrote: > > Dear Vasily Khoruzhick, > > > >> On Mon, Oct 29, 2012 at 12:57 AM, Marek Vasut wrote: > >> > Dear Vasily Khoruzhick, > >> > >> Dear Marek Vasut, > >> > >> >> This driver controls mode of USB port #2 pins - device or host. > >> > > >> > Please supply proper commit message. This short message describes > >> > nothing. > >> > >> OK, "This driver allows user to choose USB port #2 mode between device > >> and host" - that would be OK? > > > > Please describe why is this needed at all and what it does. > > Because one might need USB device and USB host functionality provided > by USB port #2? > It switches pins mode from device to host and backwards. Good, now compile it into the commit message for v3 please. > > [...] > > > >> > I wonder if we have no better means to control enforcement of mode. > >> > >> Why? sysfs fits nicely. > > > > Because if there is already an API to implement this OTG in kernel, you > > should use that and not reinvent wheel. > > One needs to select USB mode manually (btw, Z2 can't even power USB > device properly, only 3.3v or external 5v). > There's no way to determine what type of device (device/host) > connected to Z2 at the moment. Good, so your OTG is software controlled. [...] Best regards, Marek Vasut