[U-Boot] GPIO driver for Freescale QorIQ T2080

[Joakim Tjernlund]

On Wed, 2016-05-11 at 11:54 +0200, Mario Six wrote:
> On Tue, May 10, 2016 at 1:22 AM, Hamish Martin <
> Hamish.Martin at alliedtelesis.co.nz> wrote:
> 
> > 
> > Hi,
> > 
> > I'm looking for uboot driver support for the Freescale QorIQ T2080 CPU.
> > This has 4 blocks of GPIOs similar to the single block defined in
> > arch/powerpc/include/asm/mpc85xx_gpio.h.
> > 
> > If someone is working on a driver for that CPU or similar, let me know.
> > Ideally this would fit the new driver model. I'd be happy to help test
> > it out and debug it.
> > 
> > Alternatively, if you know another way to drive those GPIO blocks with
> > existing code, feel free to suggest a way.
> > 
> > Cheers,
> > Hamish Martin.
> > 
> Hi Hamish,
> 
> I posted v2 of a patch series for a MPC85xx GPIO DM driver just yesterday;
> it was
> tested on a P1022, but it's quite likely that it will work with other
> QorIQs,
> too (it's basically arpc/powerpc/include/asm/mpc85xx_gpio.h turned into a
> proper DM driver).

I have not read you patch but I wanted to mention a defect in QorIO:
It cannot read back the DAT register, it always read the pin values.
This means one needs to hold the DAT register in a RAM copy or risk
malfunction when using open drain etc.

See GPIO for QorIO in the kernel for details.

 Jocke