From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paul Mundt Date: Tue, 18 Sep 2012 07:22:38 +0000 Subject: Re: GPIO request failure with PCF pinmux Message-Id: <20120918072238.GM13568@linux-sh.org> List-Id: References: <6045802.ynsOILKLIK@avalon> In-Reply-To: <6045802.ynsOILKLIK@avalon> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-sh@vger.kernel.org On Fri, Sep 14, 2012 at 10:36:34PM +0200, Laurent Pinchart wrote: > And while I'm at it, trying to set the pin to the PWM function doesn't seem to > work anymore on v3.6. It looks like the pin stays configured as a GPIO. How am > I supposed to configure pinmuxing from the driver ? Documentation/pinctrl.txt > doesn't help much, and the code isn't easy to understand. There's probably no > registered mapping (whatever a mapping is), are they supposed to come from DT > ? For the moment requesting as a function as before should be fine, although it's possible that your config-as-gpio reconfig-as-function flow has tripped up some of the logic. Both were tested independently, but as you can tell I've overlooked the reuse of the same pin by the same driver in different ways case. And yes, you've hit on the next phase of the pfc rework. At present we have a GPIO shim that enables function requests via the GPIO API as before, but it's not the way we want to go forward and remains there only for backwards compatability. More work needs to be done both in the drivers and the board/platform to make use of pinctrl mappings. I have some work in progress for sh-sci, but ran out of time to get it merged for this merge window. The DT support is something else that has to be worked out. I personally have no interest in supporting DT, as I view the entire endeavour as nothing but a solution in search of a problem. If someone wants DT support for this they're welcome to hack something up, though. I won't oppose DT changes going in, regardless of whether they're ultimately a waste of time or not.