From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marek Vasut Date: Wed, 6 Nov 2019 23:00:25 +0100 Subject: [U-Boot] [RESEND PATCH 3/5] usb: host: dwc2: force reset assert In-Reply-To: <3e13407a0c24443fb5325318de75e357@SFHDAG6NODE3.st.com> References: <20191014080025.11245-1-patrick.delaunay@st.com> <20191014080025.11245-4-patrick.delaunay@st.com> <3e13407a0c24443fb5325318de75e357@SFHDAG6NODE3.st.com> Message-ID: <5e90369b-c273-028e-ee27-bfd7249ae64e@denx.de> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On 11/6/19 7:27 PM, Patrick DELAUNAY wrote: > Hi, Hi, [...] >>> diff --git a/drivers/usb/host/dwc2.c b/drivers/usb/host/dwc2.c index >>> 51023b0c2c..3086411fc4 100644 >>> --- a/drivers/usb/host/dwc2.c >>> +++ b/drivers/usb/host/dwc2.c >>> @@ -1149,6 +1149,8 @@ static int dwc2_reset(struct udevice *dev) >>> return ret; >>> } >>> >>> + reset_assert_bulk(&priv->resets); >>> + udelay(2); >> >> Why is there a 2 uS delay ? > > I think: no real reason to have 2 us.... > > It was jus a reasonable time to be sure that the device reset is correctly > performed, the reset signal is propagated.... > > but perhaps that no delay is working... > I can test without delay if you prefer... > > PS: I use the same value than DWC2 gadget driver: > Added by my commit c2c74f97afff Isn't there a way to poll the IP to determine whether the reset completed ? [...] -- Best regards, Marek Vasut