[PATCH] PCI: amlogic: Fix reset assertion via gpio descriptor

Remi Pommarel repk at triplefau.lt
Mon Sep 2 07:43:07 PDT 2019


On Mon, Sep 02, 2019 at 11:55:36AM +0100, Andrew Murray wrote:
> On Sun, Sep 01, 2019 at 03:39:15PM +0200, Remi Pommarel wrote:
> > Normally asserting reset signal on gpio would be achieved with:
> > 	gpiod_set_value_cansleep(reset_gpio, 1);
> > 
> > Meson PCI driver set reset value to '0' instead of '1' as it takes into
> > account the PERST# signal polarity. The polarity should be taken care
> > in the device tree instead.
> > 
> > This fixes the reset assertion meaning and moves out the polarity
> > configuration in DT (please note that there is no DT currently using
> > this driver).
> 
> The device tree bindings for this give an example configuration:
> 
>         pcie: pcie at f9800000 {
>                         compatible = "amlogic,axg-pcie", "snps,dw-pcie";
>                         reg = <0x0 0xf9800000 0x0 0x400000
>                                         0x0 0xff646000 0x0 0x2000
>                                         0x0 0xff644000 0x0 0x2000
>                                         0x0 0xf9f00000 0x0 0x100000>;
>                         reg-names = "elbi", "cfg", "phy", "config";
>                         reset-gpios = <&gpio GPIOX_19 GPIO_ACTIVE_HIGH>;
> 
> Is the 'reset-gpios' line still consistent with this change, or does
> this need to be updated as well?

Good catch, the polarity of the reset gpio will more likely be
GPIO_ACTIVE_LOW.

Do you want a separate patch for that or can I just include it in v2 ?

Thanks.

-- 
Remi



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