Re: mfd: Core driver for Winbond chips

From: Guenter Roeck
Date: Tue Apr 09 2013 - 07:36:40 EST


On Tue, Apr 09, 2013 at 11:37:01AM +0200, Samuel Ortiz wrote:
> Hi Guenter,
>
> On Sat, Mar 23, 2013 at 10:49:14AM -0700, Guenter Roeck wrote:
> > MFD core driver for various variants of Winbond/Nuvoton SuperIO chips.
> >
> > Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
> > ---
> > drivers/mfd/Kconfig | 22 +++
> > drivers/mfd/Makefile | 1 +
> > drivers/mfd/w83627hf-core.c | 324 ++++++++++++++++++++++++++++++++++++++++++
> > include/linux/mfd/w83627hf.h | 131 +++++++++++++++++
> > 4 files changed, 478 insertions(+)
> > create mode 100644 drivers/mfd/w83627hf-core.c
> > create mode 100644 include/linux/mfd/w83627hf.h
> This driver looks overall good to me. Is this your final version, or should I
> expect any follow up patch ?
>
Hi Samuel,

I was waiting for feedback from Wim, who submitted a similar driver, about his
thoughts. Key question is how to reserve access to the shared resource - either
through an exported function in the mfd driver requesting a mutex, or through
request_muxed_region(). I am going back and forth myself on which one is better.

Maybe it does not really matter, but using a function has the slight advantage
that it auto-loads and locks the mfd module while one of its client modules
is loaded. If we use request_muxed_region, that is not the case and the client
module must use another means to request and lock the mfd module.

Maybe you have an opinion ?

Thanks,
Guenter
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/