On Mon, 2017-11-27 at 16:54 +0300, Mika Westerberg wrote:
> Hi,
>
> It turns out that the Cannon Lake GPIO driver in Windows uses
> different
> GPIO numbering scheme than what Linux uses. Instead of hardware
> numbers it
> has "banks" of 32 pins even if the hardware group actually does not
> have
> that many pins. This is problematic for Linux because BIOS uses the
> same
> Windows numbering scheme in ACPI GpioIo/GpioInt resources, making
> Linux to
> pick a wrong pin.
>
> For example the SD card detection GPIO resource in BIOS ACPI tables
> looks
> like:
>
> GpioInt (...) {231} // vSD3_CD_B
>
> Where the real hardware number would be 180 instead of 231.
>
> Unfortunately changing the BIOS and the Windows driver is not possible
> for
> Cannon Lake anymore so we need to handle it in Linux instead. This
> should
> be done properly in future platforms.
>
> The patch series updates the Intel pinctrl driver to allow passing
> custom
> GPIO number space, taking advantage of pin ranges supported by the
> pinctrl
> core. However, before we can add these pin ranges we need to drop the
> custom Cherryview GPIO/ACPI translation first and make the driver to
> use
> direct mapping instead (which turns out to be much simpler).
>
> Once that is done we update the Cannon Lake pinctrl driver to align
> with
> the Windows GPIO driver numbering scheme.
For all three:
Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
>
> Mika Westerberg (3):
> gpio / ACPI: Drop unnecessary ACPI GPIO to Linux GPIO translation
> pinctrl: intel: Allow custom GPIO base for pad groups
> pinctrl: cannonlake: Align GPIO number space with Windows
>
> drivers/gpio/gpiolib-acpi.c | 75 +-------------
> drivers/pinctrl/intel/pinctrl-cannonlake.c | 65 ++++++------
> drivers/pinctrl/intel/pinctrl-cherryview.c | 59 ++++-------
> drivers/pinctrl/intel/pinctrl-intel.c | 156
> +++++++++++++++++++++--------
> drivers/pinctrl/intel/pinctrl-intel.h | 3 +
> 5 files changed, 176 insertions(+), 182 deletions(-)
>
--
Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Intel Finland Oy
--
To unsubscribe from this list: send the line "unsubscribe linux-acpi" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
