Hi Maintainer, Thanks so much for the quick reply. I would like to back ported to older kernels, but I can not figure out to which version is suitable, I can have a check later But merge into the new release version is also acceptable as I think. Thanks again. B.R Yuan Fang -----邮件原件----- 发件人: Greg KH [mailto:gregkh@xxxxxxxxxxxxxxxxxxx] 发送时间: 2021年6月11日 15:26 收件人: Yuan Fang 抄送: linux-usb@xxxxxxxxxxxxxxx; balbi@xxxxxxxxxx; Fang, Yuan 主题: Re: [PATCH] drivers/usb/dwc3: Set PHY ready after soft reset done On Fri, Jun 11, 2021 at 03:18:05PM +0800, Yuan Fang wrote: > It's more safe to set PHY ready after soft reset done > > Let's consider a test case like this: > I have a usb PHY which don't need SW initial before access it, But i > have a wrong PHY clock default setting in PHY register which means PHY > is not ready in fact. > in dwc3_core_init, dwc3_core_get_phy will return 0 despite usb get > PHYs with return -ENODEV, and set phys_ready=true but at this point, > we can not say phys is ready or at least it not safe to do that. > then, go on with dwc3_core_soft_reset,dwc3 reset core and PHY, as > phy->init is NULL in this case, so, usb_phy_init do nothing and go on > with a while loop which cost 1000* > 20 ms, and return with -ETIMEDOUT > check phys_ready is set to TRUE but actually not. > Move phys_ready after soft reset done is more reasonable and don't see > side-effect yet. > > Signed-off-by: Yuan Fang <yuan.fang@xxxxxxxxxxxxxxx> What commit does this "fix"? Should it also be backported to older kernels? If so, how far back? thanks, greg k-h
