From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lee Jones Subject: Re: [PATCH v3 03/16] mfd: mfd-core: match device tree node against reg property Date: Mon, 8 Jun 2020 19:45:07 +0100 Message-ID: <20200608184507.GC4106@dell> References: <20200423174543.17161-1-michael@walle.cc> <20200423174543.17161-4-michael@walle.cc> <67e90dafd67c285158c2c6f67f92edb7@walle.cc> <20200515102848.GH271301@dell> <159e68b4ce53630ef906b2fcbca925bd@walle.cc> <20200608142413.GA4106@dell> <7566ef30fea9740f427f392aabde0eac@walle.cc> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Return-path: Content-Disposition: inline In-Reply-To: <7566ef30fea9740f427f392aabde0eac-QKn5cuLxLXY@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Michael Walle Cc: Andy Shevchenko , Linus Walleij , Bartosz Golaszewski , Rob Herring , Jean Delvare , Guenter Roeck , Thierry Reding , Uwe =?iso-8859-1?Q?Kleine-K=F6nig?= , Wim Van Sebroeck , Shawn Guo , Li Yang , Thomas Gleixner , Jason Cooper , Marc Zyngier , Mark Brown , Greg Kroah-Hartman , linux-gpio-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-hwmon-u79uwXL29TaqPxH82wqD4g@public.gmane.org List-Id: linux-pwm@vger.kernel.org On Mon, 08 Jun 2020, Michael Walle wrote: > Am 2020-06-08 16:24, schrieb Lee Jones: > > On Mon, 25 May 2020, Michael Walle wrote: > > > Am 2020-05-15 12:28, schrieb Lee Jones: > > > > On Thu, 30 Apr 2020, Michael Walle wrote: > > > > > > > > > Hi Lee, > > > > > > > > > > Am 2020-04-23 19:45, schrieb Michael Walle: > > > > > > There might be multiple children with the device tree compatible, for > > > > > > example if a MFD has multiple instances of the same function. In this > > > > > > case only the first is matched and the other children get a wrong > > > > > > of_node reference. > > > > > > Add a new option to match also against the unit address of the child > > > > > > node. Additonally, a new helper OF_MFD_CELL_REG is added. > > > > [...] > > > > > > > > diff --git a/include/linux/mfd/core.h b/include/linux/mfd/core.h > > > > > > index d01d1299e49d..c2c0ad6b14f3 100644 > > > > > > --- a/include/linux/mfd/core.h > > > > > > +++ b/include/linux/mfd/core.h > > > > > > @@ -13,8 +13,11 @@ > > > > > > #include > > > > > > > > > > > > #define MFD_RES_SIZE(arr) (sizeof(arr) / sizeof(struct resource)) > > > > > > +#define MFD_OF_REG_VALID BIT(31) > > > > > > > > What about 64bit platforms? > > > > > > The idea was to have this as a logical number. I.e. for now you may > > > only > > > have one subdevice per unique compatible string. In fact, if you > > > have a > > > look at the ab8500.c, there are multiple "stericsson,ab8500-pwm" > > > subdevices. But there is only one DT node for all three of it. I guess > > > this works as long as you don't use phandles to reference the pwm node > > > in the device tree. Or you don't want to use device tree properties > > > per subdevice (for example the "timeout-sec" of a watchdog device). > > > > This is not a good example, as the "stericsson,ab8500-pwm" is > > legitimate. Here we are registering 3 potential devices, but only > > instantiating 1 of them. > > Mh? > > static const struct mfd_cell ab8500_devs[] = { > .. > OF_MFD_CELL("ab8500-pwm", > NULL, NULL, 0, 1, "stericsson,ab8500-pwm"), > OF_MFD_CELL("ab8500-pwm", > NULL, NULL, 0, 2, "stericsson,ab8500-pwm"), > OF_MFD_CELL("ab8500-pwm", > NULL, NULL, 0, 3, "stericsson,ab8500-pwm"), > .. > } > > And in pwm-ab8500.c there are three offsets based on the pdev->id. > > Am I missing something here? Scrap what I said above. For some reason I had of_platform_populate() in my head. This will register and enumerate 3 devices. -- Lee Jones [李琼斯] Senior Technical Lead - Developer Services Linaro.org │ Open source software for Arm SoCs Follow Linaro: Facebook | Twitter | Blog