On Monday, November 03, 2014 02:22:10 PM Linus Walleij wrote:
> On Sat, Oct 25, 2014 at 12:05 AM, Rafael J. Wysocki <rjw@xxxxxxxxxxxxx> wrote:
>
> > From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
> >
> > Provide a way for device drivers using GPIOs described by ACPI
> > GpioIo resources in _CRS to tell the GPIO subsystem what names
> > (connection IDs) to associate with specific GPIO pins defined
> > in there.
> >
> > To do that, a driver needs to define a mapping table as a
> > NULL-terminated array of struct acpi_gpio_mapping objects
> > that each contain a name, a pointer to an array of pin data
> > (struct acpi_gpio_params) objects and the size of that array.
> >
> > Each struct acpi_gpio_params object consists of three fields,
> > crs_entry_index, pin_index, active_low, representing the index of
>
> I prefer that you call the second thing "line_index" rather than
> "pin_index". Not all GPIOs in the world are tied to physical pins.
> Also it is easy to confuse stuff with the pin control terminology
> if it's called "pin".
>
> > the target GpioIo()/GpioInt() resource in _CRS starting from zero,
> > the index of the target pin in that resource starting from zero,
> > and the active-low flag for that pin, respectively.
> >
> > Next, the mapping table needs to be passed as the second argument to
> > acpi_dev_add_driver_gpios() that will register it with the ACPI device
> > object pointed to by its first argument. That object must represent
> > the ACPI namespace node containing the _CRS object referred to by the
> > GPIO mapping. That should be done in the driver's .probe() routine.
> >
> > On removal, the driver should unregister its GPIO mapping table
> > by calling acpi_dev_remove_driver_gpios() on the ACPI device
> > object where that table was previously registered.
> >
> > Included are fixes from Mika Westerberg.
> >
> > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
>
> And "pin" is mentioned several times in the commit message.
> I prefer that we talk about "lines".
>
> (...)
>
> > +struct acpi_gpio_params {
> > + unsigned int crs_entry_index;
> > + unsigned int pin_index;
>
> So line_index;
>
> > + bool active_low;
> > +};
>
> With that change:
> Reviewed-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
OK, made the changes and added your Reviewed-by.
One semi-related question though. Alexandre ACKed the patch before, so
what did that mean from the GPIO subsystem's perspective? Was the patch
approved, not approved, semi-approved?
Rafael
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