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 1lBvaW-0003w3-0u for barebox@lists.infradead.org; Tue, 16 Feb 2021 08:20:04 +0000 Date: Tue, 16 Feb 2021 09:20:01 +0100 From: Michael Grzeschik Message-ID: <20210216082001.GB16279@pengutronix.de> References: <20210118190923.531-1-m.grzeschik@pengutronix.de> MIME-Version: 1.0 In-Reply-To: List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============4010703628670229986==" 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: Ahmad Fatoum Cc: barebox@lists.infradead.org --===============4010703628670229986== Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="LyciRD1jyfeSSjG0" Content-Disposition: inline --LyciRD1jyfeSSjG0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi! On Thu, Feb 11, 2021 at 01:03:54PM +0100, Ahmad Fatoum wrote: >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 behi= nd >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 I have reproduced that. My latest findings are that, when I debugged this, usb core on my board I was debugging was behaving uncommon. It was not setting the USB_PORT_STAT_C_CONNECTION in the first place. But the further patches I send did solve this. So this whole issue was due to an uncorrect configured over-current polarity setup. With my other patches applied I see this bit USB_PORT_STAT_C_CONNECTION set even without the power-cycle. My suggestion is to _revert_ this patch, as it is solving a bogus problem not related to the whole usb-core state machine. Thanks for testing! Michael >> >> 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 *us= b_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() >=3D hub->connect_timeout) { >> dev_dbg(&dev->dev, "port%d: timeout\n", port + 1); >> /* Remove this device from scanning list */ >> --=20 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 | --LyciRD1jyfeSSjG0 Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEElXvEUs6VPX6mDPT8C+njFXoeLGQFAmArgCsACgkQC+njFXoe LGTUVg//Z1tEB5tz1ltl2Qdk4tmkWeWp0/QMkG8J4L7ATPv9dwVJ7dahcoQ+qNdB uUDDgZowAatBCujcox7PlNgLc0dhZFhvZL3vkcPk08InOPoRD1GVwUQ44Azu/Fg/ CqQ934GU0DMq9zuw+PGgaKGUyyaRs7vzo/2eQkM+SCWKsmRGqFWOJPfDu3pt2gB4 RA/ihv6if1epEmJF6rJwPzY2T8ZJ7iS2nX4+8Fe4fkbMaWbl9oa14/uGiG7Z0a4H /zdlFnVRGy7Qv1Ga1nB6FhrOizKaiY+olbryDfVks+dnsqWzkEXDnU3V2cSTA5Dg 4I+Guf89ADYVh5LhxugiV1MgTnVRdZoylJx7JVSkmLQlBuMdniDnEczEy1F4RJoK bwKSfBB2pHD14xERoFMuCxAqAu+Tsj1fjzLUW524a15xffJaFEpD8+LPWxvJAbDc iCM/Hykf9lQvxC0RUaamte2rHkSxJ2SocV6gl5mVQwoneZxpQSpDjqTM5QowahI4 aAq58GQyKnAZD1sJtzbs0mzMlYYXU1jia/2+iFh6lIv/lseLLoAMjV+FPfRlrX8P cxXR49JlFlfqAQUyseItjEEVQ2gVY/eDv2hDrkd6sc32GSeM1aS3mkOKk5c/7Zva HaiHV7Mb63tzfjnsYIW87wktPclhetPLf8l1frmR0840t/XMER0= =iKLF -----END PGP SIGNATURE----- --LyciRD1jyfeSSjG0-- --===============4010703628670229986== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox --===============4010703628670229986==--