RE: [PATCH v3 6/7] platform/mellanox: Introduce support for Mellanox register access driver

[Vadim Pasternak]

> -----Original Message-----
> From: Darren Hart [mailto:dvhart@xxxxxxxxxxxxx]
> Sent: Friday, June 01, 2018 7:53 PM
> To: Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx>
> Cc: Vadim Pasternak <vadimp@xxxxxxxxxxxx>; andy.shevchenko@xxxxxxxxx;
> linux-kernel@xxxxxxxxxxxxxxx; platform-driver-x86@xxxxxxxxxxxxxxx;
> jiri@xxxxxxxxxxx; Michael Shych <michaelsh@xxxxxxxxxxxx>;
> ivecera@xxxxxxxxxx
> Subject: Re: [PATCH v3 6/7] platform/mellanox: Introduce support for Mellanox
> register access driver
> 
> On Sun, May 27, 2018 at 05:34:45PM +0200, Greg Kroah-Hartman wrote:
> > On Sun, May 27, 2018 at 03:22:06PM +0000, Vadim Pasternak wrote:
> > >
> > >
> > > > -----Original Message-----
> > > > From: Greg KH [mailto:gregkh@xxxxxxxxxxxxxxxxxxx]
> > > > Sent: Sunday, May 27, 2018 6:14 PM
> > > > To: Vadim Pasternak <vadimp@xxxxxxxxxxxx>
> > > > Cc: dvhart@xxxxxxxxxxxxx; andy.shevchenko@xxxxxxxxx; linux-
> > > > kernel@xxxxxxxxxxxxxxx; platform-driver-x86@xxxxxxxxxxxxxxx;
> > > > jiri@xxxxxxxxxxx; Michael Shych <michaelsh@xxxxxxxxxxxx>;
> > > > ivecera@xxxxxxxxxx
> > > > Subject: Re: [PATCH v3 6/7] platform/mellanox: Introduce support
> > > > for Mellanox register access driver
> > > >
> > > > On Sun, May 27, 2018 at 04:47:43PM +0000, Vadim Pasternak wrote:
> > > > > Introduce new Mellanox platform driver to allow access to
> > > > > Mellanox programmable device register space trough sysfs interface.
> > > > > The driver purpose is to provide sysfs interface for user space
> > > > > for the registers essential for system control and monitoring.
> > > > > The sets of registers for sysfs access are supposed to be
> > > > > defined per system type bases and include the registers related
> > > > > to system resets operation, system reset causes monitoring and some
> kinds of mux selection.
> > > > >
> > > > > Signed-off-by: Vadim Pasternak <vadimp@xxxxxxxxxxxx>
> > > > > ---
> > > > > v1->v2:
> > > > >  Changed added by Vadim:
> > > > >  - Change ---help--- to help in Kconfig, according to new
> > > > > requirements;
> > > > > v2->v3:
> > > > >  Comments pointed out by Darren:
> > > > >  - Remove conditional assignment per attribute mode type, because
> mode
> > > > >    will guard against not permitted access.
> > > > >    Verified by Vadim.
> > > > > ---
> > > > >  drivers/platform/mellanox/Kconfig     |  11 ++
> > > > >  drivers/platform/mellanox/Makefile    |   1 +
> > > > >  drivers/platform/mellanox/mlxreg-io.c | 203
> > > > > ++++++++++++++++++++++++++++++++++
> > > > >  3 files changed, 215 insertions(+)  create mode 100644
> > > > > drivers/platform/mellanox/mlxreg-io.c
> > > > >
> > > > > diff --git a/drivers/platform/mellanox/Kconfig
> > > > > b/drivers/platform/mellanox/Kconfig
> > > > > index 591bccd..ddfae9fc 100644
> > > > > --- a/drivers/platform/mellanox/Kconfig
> > > > > +++ b/drivers/platform/mellanox/Kconfig
> > > > > @@ -23,4 +23,15 @@ config MLXREG_HOTPLUG
> > > > >  	  This driver handles hot-plug events for the power suppliers, power
> > > > >  	  cables and fans on the wide range Mellanox IB and Ethernet systems.
> > > > >
> > > > > +config MLXREG_IO
> > > > > +	tristate "Mellanox platform register access driver support"
> > > > > +	depends on REGMAP
> > > > > +	depends on HWMON
> > > > > +	help
> > > > > +	  This driver allows access to Mellanox programmable device
> register
> > > > > +	  space trough sysfs interface. The sets of registers for sysfs
> access
> > > > > +	  are defined per system type bases and includes the registers
> related
> > > > > +	  to system resets operation, system reset causes monitoring
> and some
> > > > > +	  kinds of mux selection.
> > > >
> > > > No Documentation/ABI/ entries for these new sysfs files?  Not good
> > > > :(
> > > >
> > >
> > > Thanks Greg for your comment.
> > >
> > > Should I call doc file like:
> > > Documentation/ABI/stable/sysfs-driver-mlxreg-io
> > > ?
> >
> > What ever matches the naming scheme for the driver, yes.
> 
> Vadim, I'm happy to help out with the docs if you like.
> 
> Will you be able to document this in a static way, or is this likely to change
> significantly from platform to platform? I ask because of the automated
> attribute creation in the code.
> 
> 
Hi Darren,

Will be great if you can help.
I actually already sent next version of patch with this file.
It'll be not have significant differences  between the different
platforms. However it'll be not the same.
I didn't mention I my file the systems for which the particular
attributes are relevant.

Thanks,
Vadim.

> --
> Darren Hart
> VMware Open Source Technology Center