From mboxrd@z Thu Jan 1 00:00:00 1970 From: thomas.petazzoni@free-electrons.com (Thomas Petazzoni) Date: Thu, 24 Apr 2014 15:26:20 +0200 Subject: [PATCH v2 0/7] ARM: berlin: add pinctrl support In-Reply-To: References: <1398268276-9696-1-git-send-email-antoine.tenart@free-electrons.com> Message-ID: <20140424152620.39eae472@skate> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Dear Linus Walleij, On Thu, 24 Apr 2014 14:52:20 +0200, Linus Walleij wrote: > > Tested on the Berlin BG2Q. > > So now I need some advice from the mvebu pinctrl maintainers > (Thomas, Sebastian etc): > > - Is this a totally different pin controller so that drivers/pinctrl/mvebu > can not be used? It is. The CPU families are completely different, made from completely separate divisions of Marvell. Just think that they come from different companies :-) On the mvebu side, each pin can be independently configured to a different function: there is a 4-bits field for each pin to configure the function. On the berlin side, pins are only configured in groups. You can't independently set the functions of each pin: you can set a function to a pre-defined set of pins. > - Really? Yes. > - OK can you help me review this thing? Sure. I believe Sebastian already had a very detailed look so he can provide his review. > - Should the base folder really be named "berlin" or is this going to > be part of a bigger family of pin controllers so a more neutral name > should be sought? berlin is the name of the mach- directory in arch/arm, and that's really the code name for this SoC family. > - Why do hardware engineers seek to reinvent wheels like pin > controllers, GPIO and DMA engines all the time :-/ I guess Russell already gave you a good answer to this question :-) Thomas -- Thomas Petazzoni, CTO, Free Electrons Embedded Linux, Kernel and Android engineering http://free-electrons.com