[PATCH] ARM: imx6: Fix PCIe reset gpio polarity on Toradex Apalis

Bjorn Helgaas
2016-04-20T00:48:55Z

On Fri, Apr 01, 2016 at 02:41:46PM +0200, Petr ?tetiar wrote:
> In commit 5c5fb40de8f14 "PCI: imx6: Add support for active-low reset GPIO"
> I've made GPIO reset polarity aware, which made the PCIe working on Apalis SoM
> (reset active-high), but it has broken PCIe on several other i.MX6 boards
> (reset active-low) due to wrong logic level. It has made the default reset
> logic active-high, but it was active-low since beginning due to the bug in the
> reset code:
>
> gpio_set_value_cansleep(imx6_pcie->reset_gpio, 0);
> msleep(100);
> gpio_set_value_cansleep(imx6_pcie->reset_gpio, 1);
>
> This breakage couldn't be fixed correctly by fixing the reset code snippet
> mentioned above and fixing the broken DTBs, as we can't touch the DTBs, so the
> 5c5fb40de8f14 commit is going to be reverted, making PCIe reset broken on
> Apalis modules again.
>
> As suggested by Fabio, to fix this situation in backward compatible manner, we
> should introduce new boolean DT property reset-gpio-active-high, which would
> set PCIe reset GPIO polarity as needed. This patch series tries to do so.

I applied both of these (the original Toradex Apalis Ixora DTS fix and
the v3 "Add reset-gpio-active-high" change) to pci/host-imx6 for v4.7,
with Lucas' Reviewed-by, Rob's Acked-by, and Tim's Tested-by. Thanks,
Petr!