Re: [RFC] Freescale MC13783 PMIC support

[Sascha Hauer <s.hauer@pengutronix.de>]

Hi Antonio,

On Tue, Aug 11, 2009 at 02:05:00PM +0200, Antonio Ospite wrote:
> On Tue, 11 Aug 2009 11:07:42 +0200
> Sascha Hauer <s.hauer@pengutronix.de> wrote:
> 
> > Hi all,
> > 
> > This series adds support for the Freescale MC13783 PMIC. The MC13783
> > is connected via SPI, the first patch adds basic support for it in
> > drivers/mfd. The rest of the patches can be applied independently.
> > Individual Maintainers are on Cc, the whole series can be found on
> > lkml and the Arm Linux Kernel mailing list.
> > Please ignore the previous mail which lacked the intrductory mail.
> > 
> > Sascha
> >
> 
> Hi Sascha,
> 
> the MC13783 is also named Atlas, isn't it?
> Maybe you can add this name somewhere in comments or in Kconfig entry
> to help greppers and web crawlers.
> 
> BTW, I only took a very brief look to some of your patches, and here's
> some humble thoughts, sorry if I don't comment patch by patch.
> 
> There is a driver queued for inclusion in 2.6.31 for the PCAP2
> PMIC, which is quite similar to MC13783. This driver uses the irq_chip
> mechanism to expose the PMIC IRQs to be used as general IRQs in
> sub-devices drivers (which you call client-devices AFAICS).

I can change the driver if there's consensus to do so.

> Also, it
> passed all the reviews so maybe you can give it a look to take some
> other solution already accepted by reviewers, like passing sub-devices
> via platform data (some of the phones which use PCAP2 don't have
> touchscreen, for instance),

This is indeed a useful feature. What I don't like about the pcap
approach is that the generation of the correct struct pcap_subdev
devices with the correct names is left to the board code.
Maybe we can also use the flags approach I already started with
MC13783_USE_TOUCHSCREEN which can be passed to the platform_data?

> generalize the driver so to handle multiple
> PMICs in one system (quite unlikely scenario?),

All functions take a struct mc13783 * so I think it should work with
multiple PMICs already.

> read actual pressure
> in TS driver.

This is left as an exercise for people who have the hardware which
supports this feature ;)

Sascha


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