From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from metis.ext.pengutronix.de ([2001:6f8:1178:4:290:27ff:fe1d:cc33]) by merlin.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1T74lU-0004Pm-Rt for barebox@lists.infradead.org; Thu, 30 Aug 2012 13:26:33 +0000 Date: Thu, 30 Aug 2012 15:26:31 +0200 From: Steffen Trumtrar Message-ID: <20120830132631.GA20930@pengutronix.de> References: <1346329850-3866-1-git-send-email-s.trumtrar@pengutronix.de> <1346329850-3866-4-git-send-email-s.trumtrar@pengutronix.de> <20120830150350.4ba00098@eb-e6520> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20120830150350.4ba00098@eb-e6520> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Sender: barebox-bounces@lists.infradead.org Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: Re: [PATCH 3/3] usb: use ep-specific pwrgood delay To: Eric =?iso-8859-1?Q?B=E9nard?= Cc: barebox@lists.infradead.org Hi Eric, > Hi Steffen, > = > Le Thu, 30 Aug 2012 14:30:50 +0200, > Steffen Trumtrar a =E9crit : > = > > In usb_hub_configure the hub is asked for its descriptor and among othe= r things > > its bPwrOn2PwrGood time. In the actual hub_power_on function this infor= mation > > was not used and a hardcoded value was used instead. For some hubs this= delay > > is to short. So, use the delay the hub wants. > > = > > Signed-off-by: Steffen Trumtrar > > Signed-off-by: Michael Grzeschik > > --- > > drivers/usb/core/usb.c | 3 ++- > > 1 file changed, 2 insertions(+), 1 deletion(-) > > = > > diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c > > index 81ae9f1..48bc121 100644 > > --- a/drivers/usb/core/usb.c > > +++ b/drivers/usb/core/usb.c > > @@ -948,7 +948,8 @@ static void usb_hub_power_on(struct usb_hub_device = *hub) > > usb_set_port_feature(dev, i + 1, USB_PORT_FEAT_POWER); > > USB_HUB_PRINTF("port %d returns %lX\n", i + 1, dev->status); > > } > > - mdelay(20); > > + /* power on is encoded in 2ms increments -> times 2 for the actual de= lay */ > > + mdelay(hub->desc.bPwrOn2PwrGood*2); > > } > > = > > #define MAX_TRIES 5 > = > I tested you patch on my MX35 board and it doesn't work (the hub > requires 50 ms, the mdelay is thus 100 ms and in the end that's not > enough to see the USB mass storage connected to the hub) but > mdelay(hub->desc.bPwrOn2PwrGood*3) works fine. > Is it possible to increase this delay (*3 instead of *2) ? > = > Thanks > Eric > = Where does your 50ms come from? From the debug messages of the usb-tool? It has the same factor of times 2. Have you tried hardcoding mdelay(100)? I first thought about doing it the same way linux does it and use max(pwrgood, 100). But 100ms minimum wouldn't help you either. I don't really like the idea of just guessing a value. But if necessary, I'm surely willing to change this patch. Greetings Steffen -- = Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox