From mboxrd@z Thu Jan 1 00:00:00 1970 From: Laurent Pinchart Subject: Re: [PATCH] media: i2c: adv7343: fix the DT binding properties Date: Mon, 23 Sep 2013 13:50:51 +0200 Message-ID: <3002978.Cb6jL1xtkE@avalon> References: <1379073471-7244-1-git-send-email-prabhakar.csengg@gmail.com> <523C1AE0.9020603@samsung.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Return-path: In-Reply-To: Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Prabhakar Lad Cc: Sylwester Nawrocki , Stephen Warren , DLOS , LMML , "devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , LAK , Sekhar Nori , LDOC , Rob Herring , Hans Verkuil , Pawel Moll , Mark Rutland , Ian Campbell , Rob Landley , Sakari Ailus List-Id: devicetree@vger.kernel.org On Monday 23 September 2013 08:18:52 Prabhakar Lad wrote: > On Fri, Sep 20, 2013 at 3:22 PM, Sylwester Nawrocki wrote: > > On 09/20/2013 10:11 AM, Prabhakar Lad wrote: > >> OK I will, just send out a fix up patch which fixes the mismatch between > >> names for the rc-cycle, and later send out a patch which removes the > >> platform data usage for next release with proper DT bindings. > > > > I think the binding need to be fully corrected now, I just meant to not > > touch the board file, i.e. leave non-dt support unchanged. > > Ok > > >> I'm OK with making regulator properties as optional, But still it would > >> change the meaning of what DT is, we know that the VDD/VDD_IO .. etc > >> pins are required properties (but still making them as optional) :-( > >> > >> I think there might several devices where this situation may arise so > >> just thinking of a alternative solution. > >> > >> say we have property 'software-regulator' which takes true/false(0/1) > >> If set to true we make the regulators as required property or else we > >> assume it is handled and ignore it ? > > > > I don't think this is a good idea. You would have to add a similar > > platform data flag for non-dt, it doesn't sound right. I can see two > > options here: > > > > 1. Make the regulator properties mandatory and, e.g. define a fixed > > voltage GPIO regulator in DT with an empty 'gpio' property. Then > > pass a phandle to that regulator in the adv7343 *-supply properties. > > For non-dt similarly a fixed voltage regulator(s) and voltage > > supplies would need to be defined in the board files. > > > > 2. Make the properties optional and use (devm_)regulator_get_optional() > > calls in the driver (a recently added function). I must admit I don't > > fully understand description of this function, it currently looks > > pretty much same as (devm_)regulator_get(). Thus the driver would > > need to be handling regulator supplies only when non ERR_PTR() is > > returned from regulator_get_optional() and otherwise assume a non > > critical error. There is already quite a few example occurrences of > > regulator_get_optional() usage. > > Thanks for pointing it I'll choose option 2 and post the patch. Isn't regulator_get_optional() intended for devices that can have supplies unconnected in normal use ? The ADV7343 supplies are mandatory from a hardware point of view, so I think we should use regulator_get(). Otherwise the driver won't be able to tell the difference between a regulator that isn't present yet (for instance because the regulator device/driver hasn't been probed yet), which should result in deferred probing, and an always-on regulator that has been left out. -- Regards, Laurent Pinchart -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html