Re: [PATCH 1/2] misc: rtsx: Move Realtek Card Reader Driver to misc

From: Arnd Bergmann
Date: Tue Oct 24 2017 - 05:52:14 EST


On Mon, Oct 23, 2017 at 11:35 AM, Lee Jones <lee.jones@xxxxxxxxxx> wrote:
> On Thu, 19 Oct 2017, Arnd Bergmann wrote:
>
>> On Thu, Oct 19, 2017 at 5:22 AM, <rui_feng@xxxxxxxxxxxxxx> wrote:
>> > From: Rui Feng <rui_feng@xxxxxxxxxxxxxx>
>> >
>> > Because Realtek PCIE card reader driver is a pcie driver,
>> > and it bridges mmc subsystem and memstick subsystem, it's
>> > not a mfd driver. Greg and Lee Jones had a discussion about
>> > where to put the driver, the result is that misc is a good
>> > place for it, so I move all files to misc. If I don't move
>> > it to a right place, I can't add any patch for this driver.
>> >
>> > Signed-off-by: Rui Feng <rui_feng@xxxxxxxxxxxxxx>
>> > ---
>> > drivers/memstick/host/rtsx_pci_ms.c | 2 +-
>> > drivers/mfd/Kconfig | 11 -----------
>> > drivers/mfd/Makefile | 2 --
>> > drivers/misc/Kconfig | 1 +
>> > drivers/misc/Makefile | 1 +
>> > drivers/misc/realtek/Kconfig | 10 ++++++++++
>> > drivers/misc/realtek/Makefile | 3 +++
>> > drivers/{mfd => misc/realtek}/rtl8411.c | 1 -
>> > drivers/{mfd => misc/realtek}/rts5209.c | 1 -
>> > drivers/{mfd => misc/realtek}/rts5227.c | 1 -
>>
>> Thanks for redoing the patch. If Lee and Greg want to see it moved
>> here, I won't object, but I'd still like to understand the distinction better,
>> since there are likely going to be other drivers in the same situation
>> (either adding into misc or mfd) and it would be good if we can all
>> give consistent advice.
>>
>> Greg, Lee: can you come up with a simple definition of what an
>> MFD is that this driver does not fit into? What about other
>> PCI drivers like intel-lpss-pci and lpc_ich? Are they different
>> from this one or should they also be moved out of MFD?
>
> MFDs drivers don't *do* anything. They handle shared resources,
> register featureful devices residing in other subsystems and provide
> simple shared functionality pertaining to the chip as a whole.
>
> These card reader devices *are* the featureful drivers and brim with
> useful functionality.
>
> intel-lpss-pci and lpc_ich conform to the aforementioned definition.

Ok. I think we have some other drivers in MFD that fall into similar
categories as rtsx, maybe the db8500 prcmu for instance, but it
does sound like a reasonable definition. If we ever get too many
drivers like rtsx in drivers/misc, we may have to come up with a
new place for them.

For now

Acked-by: Arnd Bergmann <arnd@xxxxxxxx>

to the current patch series.

Arnd