From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kuo-Jung Su Date: Wed, 8 May 2013 13:41:57 +0800 Subject: [U-Boot] [PATCH v4 1/2] usb: ehci: add Faraday USB 2.0 EHCI support In-Reply-To: <201305080509.19149.marex@denx.de> References: <1367907970-11903-1-git-send-email-dantesu@gmail.com> <201305072342.36205.marex@denx.de> <201305080509.19149.marex@denx.de> Message-ID: List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de 2013/5/8 Marek Vasut : > Dear Kuo-Jung Su, > > [...] > >> >> --- a/common/usb_hub.c >> >> +++ b/common/usb_hub.c >> >> @@ -419,6 +419,14 @@ static int usb_hub_configure(struct usb_device >> >> *dev) >> >> >> >> portstatus = le16_to_cpu(portsts->wPortStatus); >> >> portchange = le16_to_cpu(portsts->wPortChange); >> >> >> >> +#ifdef CONFIG_USB_EHCI_FARADAY >> >> + /* Faraday EHCI needs a long long delay here */ >> >> + if (!portchange && !portstatus) { >> >> + if (get_timer(start) < 250) >> >> + continue; >> >> + } >> >> +#endif >> > >> > I'd say just call a weak function here, in case some other non-EHCI >> > compliant controller happened to need this too. btw. does it need to be >> > 250 ms or can you poll for readiness somehow ? >> >> Got it, thanks. I'll add a weak function later, >> and about the 250 ms is actually an estimated value. >> The delay time is actually board specific, it looks to me >> that it's somehow related to the number of usb host controllers >> and the attached usb flash drivers. >> >> For example: >> >> 1. A369 - FUSBH200: a usb flash driver attached >> A369 - FOTG210: nothing attached >> => no extra delay required. >> >> 2. A369 - FUSBH200: nothing attached >> A369 - FOTG210: a usb flash driver attached >> => no extra delay required. >> >> 3. A369 - FUSBH200: a usb flash driver attached >> A369 - FOTG210: a usb flash driver attached >> => The 2nd ehci host requires 200 ms extra delay to detect the attached >> device. So I put a 250ms here for safe. > > Urgh, isn't it a PHY problem then? Or can this not be solved like > board/genesi/mx51_efikamx/efikamx-usb.c board_ehci_hcd_postinit() or such > function? > It looks to me that it's something related to root hub reset. And now I've found that adding a extra delay to usb_hub_power_on() would help to resolve this issue. So I plan to add a new macro constant for it. For example: 1. Add this to README: CONFIG_USB_HUB_MIN_POWER_ON_DELAY defines the minimum interval for usb hub power-on delay.(minimum 100msec) 2. Update usb_hub.c as bellow: static void usb_hub_power_on(struct usb_hub_device *hub) { ...... /* Wait at least 100 msec for power to become stable */ mdelay(max(pgood_delay, USB_HUB_MIN_POWER_ON_DELAY)); } > [...] > > Best regards, > Marek Vasut -- Best wishes, Kuo-Jung Su