Re: [PATCH 0/3] Add SDHCI ACPI driver

Rafael J. Wysocki
2012-11-23T10:45:51Z

On Friday, November 23, 2012 12:13:13 PM Adrian Hunter wrote:
> On 23/11/12 11:34, Mika Westerberg wrote:
> > On Thu, Nov 22, 2012 at 10:24:33PM +0100, Rafael J. Wysocki wrote:
> >> On Thursday, November 22, 2012 04:46:10 PM Adrian Hunter wrote:
> >>> On 22/11/12 15:55, Chris Ball wrote:
> >>>> Hi,
> >>>>
> >>>> On Thu, Nov 22 2012, Adrian Hunter wrote:
> >>>>> Here is SDHCI ACPI driver. It is dependent on new ACPI Platform support
> >>>>> so I suggest Rafael takes the patches with Chris' Ack.
> >>>>>
> >>>>> Please note that I would prefer this to be queued for 3.8
> >>>>
> >>>> Looks fine:
> >>>>
> >>>> Acked-by: Chris Ball <cjb@laptop.org>
> >>>
> >>> Thank you!
> >>>
> >>>>
> >>>> I have some dumb questions, though -- what kind of platforms ship with
> >>>> these devices? Do they ever have the controller on PCI too, and what
> >>>> happens with sdhci-pci vs. sdhci-acpi in that case?
> >>>
> >>> Since the arrival of ACPI5, platform devices can be configured using ACPI
> >>> tables. PCI can also be used, but the firmware ensures that the same
> >>> device is not enumerated via both ACPI and PCI.
> >>>
> >>> Rafael can you take these patches?
> >>
> >> Well, I'd prefer pnpacpi/core.c to actually use acpi_platform_device_ids[]
> >> directly in addition to excluded_id_list[], so that duplicate entries don't
> >> have to be added to the both of them.
> >
> > How about having pnpacpi to check if the ACPI device is already bound to a
> > physical device and skip the device creation? Then we don't need to expose
> > the acpi_platform_device_ids[] list, and this is what the ->find_device()
> > code already does so why create the device in the first place?
>
> Yes, I was going to suggest that too. AFAICS pnpacpi has no concept of
> multiple physical nodes. Any objections?

Not from me.

Thanks,
Rafael

> > diff --git a/drivers/pnp/pnpacpi/core.c b/drivers/pnp/pnpacpi/core.c
> > index 5b17cc8..4dc2e64 100644
> > --- a/drivers/pnp/pnpacpi/core.c
> > +++ b/drivers/pnp/pnpacpi/core.c
> > @@ -243,6 +243,10 @@ static int __init pnpacpi_add_device(struct acpi_device *device)
> > char *pnpid;
> > struct acpi_hardware_id *id;
> >
> > + /* Skip devices that are already bound */
> > + if (device->physical_node_count)
> > + return 0;
> > +
> > /*
> > * If a PnPacpi device is not present , the device
> > * driver should not be loaded.
> >
> >
>
>
--
I speak only for myself.
Rafael J. Wysocki, Intel Open Source Technology Center.