Re: [PATCH] i.MX6 PCIe: Fix imx6_pcie_deassert_core_reset() polarity

From: Fabio Estevam
Date: Wed Mar 30 2016 - 08:46:18 EST


On Wed, Mar 30, 2016 at 9:06 AM, Petr Åtetiar <ynezz@xxxxxxx> wrote:

> I'm really puzzled by this :-) With your patch applied I get following on
> Toradex Apalis modules:
>
> DTS: reset-gpio = <&gpio1 28 GPIO_ACTIVE_LOW>;
> dmesg: imx6q-pcie 1ffc000.pcie: phy link never came up
> gpio: gpio-28 ( |reset ) out hi
> pin voltage: 0V
>
> DTS: reset-gpio = <&gpio1 28 GPIO_ACTIVE_HIGH>;
> dmesg: ath9k 0000:01:00.0: enabling device (0140 -> 0142)
> gpio: gpio-28 ( |reset ) out lo
> pin voltage: 3V3
>
> So Toradex Apalis is actually active-high? Thanks.

Yes, exactly. That's why you need to introduce a new property to
handle the active-high case, so that old dtb's are not broken.