From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 90682C001DC for ; Thu, 20 Jul 2023 12:49:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230417AbjGTMta (ORCPT ); Thu, 20 Jul 2023 08:49:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52208 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229477AbjGTMt2 (ORCPT ); Thu, 20 Jul 2023 08:49:28 -0400 Received: from relay1-d.mail.gandi.net (relay1-d.mail.gandi.net [IPv6:2001:4b98:dc4:8::221]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8401E2137; Thu, 20 Jul 2023 05:49:26 -0700 (PDT) Received: by mail.gandi.net (Postfix) with ESMTPSA id A276E240014; Thu, 20 Jul 2023 12:49:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1689857364; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=KM2SNsZ/HAYwDzPK1l8Fn0Kjjd/fx0+8gmsPG5KrJWc=; b=FEh8dN41ecWrK2JCCbjB9zBgE9WkGGualnGygAJrZVYFkXIxDGxSUpQykjxr0AzozyZ7cU qz7K48c92QfNUdV05PdDAbooql7esT72PoDftVnhRhv0z5LSafebmRZPVg8GdxNM112wpI 6rKWJorJxONEzQO1uNbQY3PgEoNRkEhXnJP8HczlydnmBqvFkFTRxKw7j6eMNsY38tQFT5 Pye+lsCX9jqxH9R3wowxWVVUc5ua1IG70OeATVmszNu+hYev8lenMrAwDsL2sITr3/7InS 4cjaEtZT8ky9/jYANrNEnwpxxFsV98nKM86XXin2SI9R+EYsD4SexDjroj9E8A== Date: Thu, 20 Jul 2023 14:49:16 +0200 From: Luca Ceresoli To: Xu Yang Cc: Francesco Dolcini , Jun Li , "devicetree@vger.kernel.org" , "festevam@gmail.com" , "gregkh@linuxfoundation.org" , "kernel@pengutronix.de" , "linux-arm-kernel@lists.infradead.org" , dl-linux-imx , "linux-kernel@vger.kernel.org" , "linux-usb@vger.kernel.org" , "robh+dt@kernel.org" , "s.hauer@pengutronix.de" , "shawnguo@kernel.org" , Krzysztof Kozlowski , Francesco Dolcini Subject: Re: [EXT] Re: [PATCH v2 2/3] usb: chipidea: imx: support disabling runtime-pm Message-ID: <20230720144916.01d49adb@booty> In-Reply-To: References: <20230504162312.1506763-1-luca.ceresoli@bootlin.com> <20230505120618.2f4cf22c@booty> <20230508151756.785ec07e@booty> <20230529121825.71e9b6d6@booty> <20230717184537.6d6ed607@booty> <20230718142504.075d0186@booty> <20230719184831.75ae8658@booty> Organization: Bootlin X-Mailer: Claws Mail 4.0.0 (GTK+ 3.24.33; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-GND-Sasl: luca.ceresoli@bootlin.com Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Xu, On Thu, 20 Jul 2023 10:13:57 +0000 Xu Yang wrote: > Hi Luca, > > > > > -----Original Message----- > > > > > > > > Hello Xu, > > > > > > > > On Tue, 18 Jul 2023 08:31:48 +0000 > > > > Xu Yang wrote: > > > > > > > > > > -----Original Message----- > > > > > > > > > > > > Ciao Francesco, > > > > > > > > > > > > On Thu, 6 Jul 2023 12:23:43 +0200 > > > > > > Francesco Dolcini wrote: > > > > > > > > > > > > > Hello Luca, > > > > > > > > > > > > > > On Tue, May 30, 2023 at 11:22:51AM +0000, Jun Li wrote: > > > > > > > > Yes, your understanding is correct, talked with Xu(in CC), he will take this > > > > > > > > soon. > > > > > > > > > > > > > > A series was posted > > > > > > > > > > > > > > I had no time to try or look at it yet. > > > > > > > > > > > > Thanks for keeping me up to date on this topic, which is still totally > > > > > > relevant to me. > > > > > > > > > > > > I looked at the series, but it does not seem to be addressing the > > > > > > problem with USB host not detecting new devices when VBUS is not > > > > > > directly connected, e.g. in the Colibri imx6ull SoM. > > > > > > > > > > > > Xu, do you confirm the series at the link is _not_ solving the problem > > > > > > being discussed here? > > > > > > > > > > Have you tried this patchset? The upstream driver couldn't get correct > > > > > USB role from HW_USBPHY_CTRL register when the ID pin is float. This is > > > > > what this patchset is trying to fix. With this patch, condition > > > > > "(!vbus_is_on && !mxs_phy_is_otg_host(mxs_phy)" will always be false when > > > > > controller acts as host role, then __mxs_phy_disconnect_line(phy, true) > > > > > will never be called. So I think it doesn't matter whether VBUS is connected > > > > > or not when act as host mode. If you still have issue after apply this patchset, > > > > > please let me know. > > > > > > > > I tested this patchset on top of v6.5-rc2 and I confirm USB detection > > > > is still broken on the Colibri iMX6ULL. With or without the patches > > > > the behavior is the same: USB devices are detected only during boot, > > > > and anything connected after boot are never detected. > > > > > > Thanks for your feedback. As you said this issue will disappear with below change, right? > > > > > > diff --git a/drivers/usb/phy/phy-mxs-usb.c b/drivers/usb/phy/phy-mxs-usb.c > > > index e1a2b2ea098b..ec5ee790455e 100644 > > > --- a/drivers/usb/phy/phy-mxs-usb.c > > > +++ b/drivers/usb/phy/phy-mxs-usb.c > > > @@ -178,7 +178,6 @@ static const struct mxs_phy_data imx6sx_phy_data = { > > > }; > > > > > > static const struct mxs_phy_data imx6ul_phy_data = { > > > - .flags = MXS_PHY_DISCONNECT_LINE_WITHOUT_VBUS, > > > }; > > > > > > static const struct mxs_phy_data imx7ulp_phy_data = { > > > > Exactly. > > > > > So I guess something in __mxs_phy_disconnect_line(mxs_phy, true) is causing this behavior. > > > Could you please help to find which line to comment to make this issue disappear? > > To correct what I said: __mxs_phy_disconnect_line(mxs_phy, false) should > be called. > > I think the enable wakeup sequence should be follow for host-only port: > mxs_phy_set_wakeup(mxs_phy, true) > mxs_phy_disconnect_line(mxs_phy, true); > __mxs_phy_disconnect_line(mxs_phy, false); > > And disable wakeup sequence: > mxs_phy_set_wakeup(mxs_phy, false) > mxs_phy_disconnect_line(mxs_phy, false); > __mxs_phy_disconnect_line(mxs_phy, false); > > So "bool variable disconnect is false" all the time. > > > > > I did some tests and detection works by doing _any_ of the following > > two changes (or both of them). > > > > Change 1: > > > > --- a/drivers/usb/phy/phy-mxs-usb.c > > +++ b/drivers/usb/phy/phy-mxs-usb.c > > @@ -359,10 +359,6 @@ static void __mxs_phy_disconnect_line(struct mxs_phy *mxs_phy, bool disconnect) > > void __iomem *base = mxs_phy->phy.io_priv; > > u32 reg; > > > > - if (disconnect) > > - writel_relaxed(BM_USBPHY_DEBUG_CLKGATE, > > - base + HW_USBPHY_DEBUG_CLR); > > - > > Since disconnect = false, this code didn't get executed all the time. > Remove this will have no impact. But your test results didn't align > to this. Could you please help check the sequence? Is disconnect > true or false when __mxs_phy_disconnect_line is called? What I observe is that __mxs_phy_disconnect_line(..., true) is called. This happens during boot and after unplugging a device in case one was detected during boot. This is because in mxs_phy_disconnect_line() [0]: - on = 1 - !vbus_is_on = 1 - !mxs_phy_is_otg_host(mxs_phy) = 1 Which one(s) of those three would you expect to be 0? Some additional info about the !mxs_phy_is_otg_host(mxs_phy) value: with or without CONFIG_USB_OTG, it always has the same value because phyctrl always has the BM_USBPHY_CTRL_OTG_ID_VALUE bit set. [0] https://elixir.bootlin.com/linux/v6.5-rc2/source/drivers/usb/phy/phy-mxs-usb.c#L415 Luca -- Luca Ceresoli, Bootlin Embedded Linux and Kernel engineering https://bootlin.com