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 X-Spam-Level: X-Spam-Status: No, score=-6.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2ADACC35247 for ; Tue, 4 Feb 2020 20:41:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DF24F20674 for ; Tue, 4 Feb 2020 20:41:06 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="oDz9EmeV" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727514AbgBDUlG (ORCPT ); Tue, 4 Feb 2020 15:41:06 -0500 Received: from mail-io1-f66.google.com ([209.85.166.66]:36930 "EHLO mail-io1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727444AbgBDUlF (ORCPT ); Tue, 4 Feb 2020 15:41:05 -0500 Received: by mail-io1-f66.google.com with SMTP id k24so22532613ioc.4 for ; Tue, 04 Feb 2020 12:41:05 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=wOEFiVFO7z0I5vVtCBqbR+q7KXZ5cgDDuFWgR6+ESQI=; b=oDz9EmeV2dNsaRXLclripWbOSUDtCFkMSbQgv2fEEVGhr68Z1aR47cMAXFv5OG9B+H /LAQ3AOnKe5E4sKxl/zZb4ffxZgiU0tVGXZOeaW442tynUC/PCeUXn/0kcVLgip1S+07 Ot12iNUtuq6cfx2vf18LaplgsGx9ziub4gOks= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=wOEFiVFO7z0I5vVtCBqbR+q7KXZ5cgDDuFWgR6+ESQI=; b=dJX1bTMj67c+8csPQJFvqFPaQhz3bowQjsauztx4nw5LuqN/L8KN6fOoUEU7MYLBfU Pp8ffPxUQK3cQpSQvVsIr32iw8N4YXsgcsiXmnWWHNAdhrPrcYyeqenUggsFqijzL5dm qtGCVbHfh22UbvjVgWzziOkijg8AtHpe3rpPyI1ED2k3/bmZ0NSOEKhUW7bXtlHzqQ9h rfo/kjljyXLFW1mborwHxfmO4yOvVu0A4EhZb/jryYGl5rKpG6z7UtSS5F8ghfm+0pof +TUrqDSEZHmKgXIHgjNuLbTrXcOoBd1GrUMQ9mCAxVGePLfmC3tGa+vkkjTGxiSHNG4g AG1w== X-Gm-Message-State: APjAAAWCoBrhGoFFN5lBhn8hk2QjvbESaGPCD+2gIxi0CRe2itG5IdMx vfxEEooQbt2YMa+TmBGmuIMxbBLGjDB3pQsDcvd8JA== X-Google-Smtp-Source: APXvYqyWs6qpExTQt//uPVVYWCPZ31eudUJW7D6SC26QzVPCxXKpz3W7CUi1Xoz7T61PkrX+M8wwI4okQsOWIbOn49w= X-Received: by 2002:a6b:ec0f:: with SMTP id c15mr23939350ioh.149.1580848864881; Tue, 04 Feb 2020 12:41:04 -0800 (PST) MIME-Version: 1.0 References: <20200203225356.203946-1-yichengli@chromium.org> <54cbade6-c552-4877-a8d7-d2be9930cefd@samsung.com> In-Reply-To: <54cbade6-c552-4877-a8d7-d2be9930cefd@samsung.com> From: Gwendal Grignou Date: Tue, 4 Feb 2020 12:40:51 -0800 Message-ID: Subject: Re: [PATCH v6] platform/chrome: cros_ec: Query EC protocol version if EC transitions between RO/RW To: Marek Szyprowski Cc: Yicheng Li , LKML , Benson Leung , Enric Balletbo i Serra , Guenter Roeck , Lee Jones , Andy Shevchenko , Jonathan Cameron , Evan Green , Rushikesh S Kadam , Thomas Gleixner Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Reviewed-by: Gwendal Grignou On Mon, Feb 3, 2020 at 11:30 PM Marek Szyprowski wrote: > > Hi > > On 03.02.2020 23:53, Yicheng Li wrote: > > RO and RW of EC may have different EC protocol version. If EC transitions > > between RO and RW, but AP does not reboot (this is true for fingerprint > > microcontroller / cros_fp, but not true for main ec / cros_ec), the AP > > still uses the protocol version queried before transition, which can > > cause problems. In the case of fingerprint microcontroller, this causes > > AP to send the wrong version of EC_CMD_GET_NEXT_EVENT to RO in the > > interrupt handler, which in turn prevents RO to clear the interrupt > > line to AP, in an infinite loop. > > > > Once an EC_HOST_EVENT_INTERFACE_READY is received, we know that there > > might have been a transition between RO and RW, so re-query the protocol. > > > > Signed-off-by: Yicheng Li > > Tested-by: Marek Szyprowski > > Works fine on Samsung Exynos-based Chromebooks: Snow, Peach-Pit and > Peach-Pi. > > > --- > > Hi Enric and Marek, > > > >> This patch landed recently in linux-next as commit > >> 241a69ae8ea8e2defec751fe55dac1287aa044b8. Sadly, it causes following > >> kernel oops on any key press on Samsung Exynos-based Chromebooks (Snow, > >> Peach-Pit and Peach-Pi): > > > >> Many thanks for report the issue, we will take a look ASAP and revert > >> this commit meanwhile. > > > >> Simply removing the BUG_ON() from cros_ec_get_host_event() function > >> fixes the issue, but I don't know the protocol details to judge if this > >> is the correct way of fixing it. > > The issue was those Samsung Chromebooks (Snow, Peach-Pit and Peach-Pi) > > do not support mkbp events, yet we applied the same thing to them, which > > we shouldn't. This v6 should fix it: I Just added a check > > > > if (ec_dev->mkbp_event_supported) > > > > in cros_ec_register(). > > > > > > > > drivers/platform/chrome/cros_ec.c | 29 +++++++++++++++++++++ > > include/linux/platform_data/cros_ec_proto.h | 3 +++ > > 2 files changed, 32 insertions(+) > > > > diff --git a/drivers/platform/chrome/cros_ec.c b/drivers/platform/chrome/cros_ec.c > > index 9b2d07422e17..f16804db805b 100644 > > --- a/drivers/platform/chrome/cros_ec.c > > +++ b/drivers/platform/chrome/cros_ec.c > > @@ -104,6 +104,23 @@ static int cros_ec_sleep_event(struct cros_ec_device *ec_dev, u8 sleep_event) > > return ret; > > } > > > > +static int cros_ec_ready_event(struct notifier_block *nb, > > + unsigned long queued_during_suspend, void *_notify) > > +{ > > + struct cros_ec_device *ec_dev = container_of(nb, struct cros_ec_device, > > + notifier_ready); > > + u32 host_event = cros_ec_get_host_event(ec_dev); > > + > > + if (host_event & EC_HOST_EVENT_MASK(EC_HOST_EVENT_INTERFACE_READY)) { > > + mutex_lock(&ec_dev->lock); > > + cros_ec_query_all(ec_dev); > > + mutex_unlock(&ec_dev->lock); > > + return NOTIFY_OK; > > + } > > + > > + return NOTIFY_DONE; > > +} > > + > > /** > > * cros_ec_register() - Register a new ChromeOS EC, using the provided info. > > * @ec_dev: Device to register. > > @@ -201,6 +218,18 @@ int cros_ec_register(struct cros_ec_device *ec_dev) > > dev_dbg(ec_dev->dev, "Error %d clearing sleep event to ec", > > err); > > > > + if (ec_dev->mkbp_event_supported) { > > + /* > > + * Register the notifier for EC_HOST_EVENT_INTERFACE_READY > > + * event. > > + */ > > + ec_dev->notifier_ready.notifier_call = cros_ec_ready_event; > > + err = blocking_notifier_chain_register( > > + &ec_dev->event_notifier, &ec_dev->notifier_ready); > > + if (err) > > + return err; > > + } > > + > > dev_info(dev, "Chrome EC device registered\n"); > > > > return 0; > > diff --git a/include/linux/platform_data/cros_ec_proto.h b/include/linux/platform_data/cros_ec_proto.h > > index 0d4e4aaed37a..a1c545c464e7 100644 > > --- a/include/linux/platform_data/cros_ec_proto.h > > +++ b/include/linux/platform_data/cros_ec_proto.h > > @@ -121,6 +121,8 @@ struct cros_ec_command { > > * @event_data: Raw payload transferred with the MKBP event. > > * @event_size: Size in bytes of the event data. > > * @host_event_wake_mask: Mask of host events that cause wake from suspend. > > + * @notifier_ready: The notifier_block to let the kernel re-query EC > > + * communication protocol when the EC sends EC_HOST_EVENT_INTERFACE_READY. > > * @ec: The platform_device used by the mfd driver to interface with the > > * main EC. > > * @pd: The platform_device used by the mfd driver to interface with the > > @@ -161,6 +163,7 @@ struct cros_ec_device { > > int event_size; > > u32 host_event_wake_mask; > > u32 last_resume_result; > > + struct notifier_block notifier_ready; > > > > /* The platform devices used by the mfd driver */ > > struct platform_device *ec; > > Best regards > -- > Marek Szyprowski, PhD > Samsung R&D Institute Poland >