pinctrl: Align Cannon Lake GPIO number space with Windows

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.

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(-)

2.15.0