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Re: [PATCH v2 1/4] ACPI / property: Allow holes in reference properties

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On Thu, Sep 29, 2016 at 3:39 PM, Mika Westerberg
<mika.westerberg@linux.intel.com> wrote:
> DT allows holes or empty phandles for references. This is used for example
> in SPI subsystem where some chip selects are native and others are regular
> GPIOs. In ACPI _DSD we currently do not support this but instead the
> preceding reference consumes all following integer arguments.
>
> For example we would like to support something like the below ASL fragment
> for SPI:
>
>   Package () {
>       "cs-gpios",
>       Package () {
>           ^GPIO, 19, 0, 0, // GPIO CS0
>           0,               // Native CS
>           ^GPIO, 20, 0, 0, // GPIO CS1
>       }
>   }
>
> The zero in the middle means "no entry" or NULL reference. To support this
> we change acpi_data_get_property_reference() to take firmware node and
> num_args as argument and rename it to __acpi_node_get_property_reference().
> The function returns -ENOENT if the given index resolves to "no entry"
> reference and -ENODATA when there are no more entries in the property.
>
> We then add static inline wrapper acpi_node_get_property_reference() that
> passes MAX_ACPI_REFERENCE_ARGS as num_args to support the existing
> behaviour which some drivers have been relying on.
>
> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

The patch looks good to me and I don't see any reason to defer it, so
I'm queuing it up for the next ACPI pull request.

Thanks,
Rafael

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[PATCH v2 0/4] ACPI / gpio: Updates to properties Mika Westerberg <mika.westerberg@linux.intel.com> - 2016-09-29 15:50 +0200
  [PATCH v2 1/4] ACPI / property: Allow holes in reference properties Mika Westerberg <mika.westerberg@linux.intel.com> - 2016-09-29 15:50 +0200
    Re: [PATCH v2 1/4] ACPI / property: Allow holes in reference properties "Rafael J. Wysocki" <rafael@kernel.org> - 2016-10-11 22:50 +0200
  [PATCH v2 3/4] ACPI / gpio: Add hogging support Mika Westerberg <mika.westerberg@linux.intel.com> - 2016-09-29 15:50 +0200
  [PATCH v2 4/4] ACPI / gpio: Allow holes in list of GPIOs for a device Mika Westerberg <mika.westerberg@linux.intel.com> - 2016-09-29 15:50 +0200
  Re: [PATCH v2 0/4] ACPI / gpio: Updates to properties Andy Shevchenko <andy.shevchenko@gmail.com> - 2016-10-07 19:20 +0200

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