From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1lAAhP-00042l-Q3 for barebox@lists.infradead.org; Thu, 11 Feb 2021 12:03:56 +0000 References: <20210118190923.531-1-m.grzeschik@pengutronix.de> From: Ahmad Fatoum Message-ID: Date: Thu, 11 Feb 2021 13:03:54 +0100 MIME-Version: 1.0 In-Reply-To: <20210118190923.531-1-m.grzeschik@pengutronix.de> Content-Language: en-US List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "barebox" Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: Re: [PATCH] usb: hub: fix state change check for not powercycled ports To: Michael Grzeschik , barebox@lists.infradead.org Hello, On 18.01.21 20:09, Michael Grzeschik wrote: > Since we don't power cycle the ports on start since patch "19bb0b2a usb: > hub: Do not power-cycle usb devices on init" it is possible that the > device on this port is already active from a previous enumeration. This > way barebox will never get any change in USB_PORT_STAT_C_CONNECTION bit > change. > > Although the device will probably still work fine after the following > port reset, the current code will always miss reenumerating these still > plugged devices. This patch fixes this by ignoring the check for > STAT_C_CONNECTION bit and only go for USB_PORT_STAT_CONNECTION which > should be enough. This breaks USB enumeration for me on an i.MX6Q. The USB flash driver behind the hub is detected twice, which barebox doesn't like at all: barebox@Embest MarS Board i.MX6Dual:/ usb -s usb: USB: scanning bus for devices... usb1: Bus 001 Device 001: ID 0000:0000 EHCI Host Controller usb1-0: Bus 001 Device 002: ID 1a40:0101 USB 2.0 Hub [MTT] usb1-0-1: Bus 001 Device 003: ID 058f:6387 Mass Storage Using index 0 for the new disk usb1-0-1: Bus 001 Device 004: ID 058f:6387 Mass Storage ERROR: register_device: already registered usb1-0-1 ERROR: usb1-0-1: Failed to register device: Invalid argument usb: 3 USB Device(s) found Bus 001 Device 001: ID 0000:0000 EHCI Host Controller Bus 001 Device 002: ID 1a40:0101 USB 2.0 Hub [MTT] Bus 001 Device 003: ID 058f:6387 Mass Storage This seems to corrupt some internal barebox state as reading /dev/disk0.0 will hang. Reading /dev/disk0 is fine however. With this patch reverted it however works: usb: USB: scanning bus for devices... usb1: Bus 001 Device 001: ID 0000:0000 EHCI Host Controller usb1-0: Bus 001 Device 002: ID 1a40:0101 USB 2.0 Hub [MTT] usb1-0-1: Bus 001 Device 003: ID 058f:6387 Mass Storage Using index 0 for the new disk usb: 3 USB Device(s) found Bus 001 Device 001: ID 0000:0000 EHCI Host Controller Bus 001 Device 002: ID 1a40:0101 USB 2.0 Hub [MTT] Bus 001 Device 003: ID 058f:6387 Mass Storage The USB drive is not self-powered. It doesn't make a difference whether it's done directly after cold reset or: usb -s boot bnet usb -s Cheers, Ahmad > > Signed-off-by: Michael Grzeschik > --- > drivers/usb/core/hub.c | 3 +-- > 1 file changed, 1 insertion(+), 2 deletions(-) > > diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c > index 01653d8c20..d1112248ee 100644 > --- a/drivers/usb/core/hub.c > +++ b/drivers/usb/core/hub.c > @@ -336,8 +336,7 @@ static void usb_scan_port(struct usb_device_scan *usb_scan) > dev_dbg(&dev->dev, "port%d: Status 0x%04x Change 0x%04x\n", > port + 1, portstatus, portchange); > > - if (!(portchange & USB_PORT_STAT_C_CONNECTION) || > - !(portstatus & USB_PORT_STAT_CONNECTION)) { > + if (!(portstatus & USB_PORT_STAT_CONNECTION)) { > if (get_time_ns() >= hub->connect_timeout) { > dev_dbg(&dev->dev, "port%d: timeout\n", port + 1); > /* Remove this device from scanning list */ > -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 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