Re: [PATCH v2 1/2] phy: tegra: xusb: add utmi pad power on/down ops
From: Vinod Koul
Date: Tue Sep 20 2022 - 02:36:12 EST
On 14-09-22, 10:59, JC Kuo wrote:
> On 9/13/22 22:34, Vinod Koul wrote:
> > On 06-09-22, 10:43, JC Kuo wrote:
> > Thanks for this explanation... It helps!
> >
> > Just a suggestion, can this be moved into phy_init() you have detected
> > connection in phy_power_on(), the transceiver can be enabled in
> > phy_int... Would that work?
> > That would work, too. However, because Tegra USB has separate phys for USB3 SS
> and USB2, I'd like to keep the USB2 phy operations as they are now, so that USB
> host and device controller drivers do not have to distinguish the phy type and
> invoke different phy stubs. Furthermore, PD_ZI=0 does really power on the USB2
> phy, partially.
>
> For example:
> 1. in .probe(),
> for_each_usb_phy {
> phy_init(phy);
> }
>
> for_each_usb3_phy {
> phy_power_on(phy);
> };
>
> 2. upon detecting connection,
>
> phy_power_on(the_target_usb2_phy);
It should be always phy_init() in probe and once detection
phy_power_on()
that should be generic flow for all...
--
~Vinod