Hi Arnd, > -----Original Message----- > From: Arnd Bergmann [mailto:a...@arndb.de] > Sent: Monday, September 01, 2014 4:07 PM > To: Lee Jones > Cc: Pankaj Dubey; linux-arm-ker...@lists.infradead.org; linux-samsung- > s...@vger.kernel.org; linux-kernel@vger.kernel.org; kgene....@samsung.com; > li...@arm.linux.org.uk; vikas.saj...@samsung.com; jo...@samsung.com; > naus...@samsung.com; thomas...@samsung.com; chow....@samsung.com; > Tomasz Figa; broo...@kernel.org > Subject: Re: [PATCH] mfd: syscon: Decouple syscon interface from syscon devices > > On Monday 01 September 2014 08:49:18 Lee Jones wrote: > > On Fri, 22 Aug 2014, Pankaj Dubey wrote: > > > > > From: Tomasz Figa <t.f...@samsung.com> > > > > > > Currently a syscon entity can be only registered directly through a > > > platform device that binds to a dedicated driver. However in certain > > > use cases it is desirable to make a device used with another driver > > > a syscon interface provider. For example, certain SoCs (e.g. Exynos) > > > contain system controller blocks which perform various functions > > > such as power domain control, CPU power management, low power mode > > > control, but in addition contain certain IP integration glue, such > > > as various signal masks, coprocessor power control, etc. In such > > > case, there is a need to have a dedicated driver for such system > > > controller but also share registers with other drivers. The latter > > > is where the syscon interface is helpful. > > > > > > This patch decouples syscon object from syscon driver, so that it > > > can be registered from any driver in addition to the original > > > "syscon" platform driver. > > > > > > Signed-off-by: Tomasz Figa <t.f...@samsung.com> > > > Signed-off-by: Pankaj Dubey <pankaj.du...@samsung.com> > > > --- > > > > > > RFC patch [1] was posted by Tomasz Figa. This patch addresses some > > > of comments given by Arnd to RFC patch, and further decouples syscon > > > from device model. It also gives flexibility of registering with > > > syscon at early stage using device_node object. > > > > It would be helpful if Arnd gave this revision his blessing (Ack). > > I never saw a reason why we don't take this all the way as discussed a few times: > Completely remove the dependency of syscon on having a platform driver for it, and > make it possible to just call > syscon_regmap_lookup_by_phandle() without having to register it first. >
Please have a look at this thread [1], where we discussed the need of syscon as platform device. Looks like still there are users of syscon_regmap_lookup_by_pdevname (clps711x.c). So we can't make it completely independent of platform_device. [1] https://www.mail-archive.com/linux-samsung-soc@vger.kernel.org/msg35708.html > Arnd -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/