Correct ordering of phy_init and phy_power_on

From: Ahmad Fatoum
Date: Sun Dec 20 2020 - 18:27:18 EST


Hello,

I just noticed that USB controller drivers differ in the order in which they
do phy_init and phy_power_on. For example:

__dwc2_lowlevel_hw_enable():

ret = phy_power_on(hsotg->phy);
if (ret == 0)
ret = phy_init(hsotg->phy);

dwc3_core_init():

ret = dwc3_core_soft_reset(dwc); // internally does phy_init(dwc->usb2_generic_phy);
/* [snip] */
ret = phy_power_on(dwc->usb2_generic_phy);


My initial assumption has been init -> power_on, but at least the phy-stm32-usbphyc
(used with dwc2) is written with the assumption that exit -> power_off (and therefore
power_on -> init). If they are swapped, disabling fails.

So how was it meant to be?

Cheers,
Ahmad

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