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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 8716BC7EE24 for ; Tue, 6 Jun 2023 12:13:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=luJepynxyCzwWALIqh6PW/AwWOuC+MHoTHBW4cCEMmY=; b=eu7hjb1wURBg3C iBofHu3zZcZAt8VREbJE+i0GpWJVGDXqEq3re9gBMzFBhrG1R89IzFVME4e2ZCYKVztfcJABllu2h UW2NOU6deik8MyYmfSKaKXhGRaYqSF+ocB0auMpuJch3HDzEG8DUVPpP9MsA0OiVh7CrDvIu8WLcs YlQXmNvlrfA+PyMPrOa+JYJH0u1uAjXnXhQXOVW0connyag07atxbo4J/JDVGapBibOzkSKEkns4v jJJcKv41GaZ3Mqv74wXcfiYEVInyAS/HEbvpGXQUeOfY+klpL5FTHBoZOlWbseftSECZXb8QLVl5F pySl2VooBqxJB8BZln6w==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1q6VZ8-001anQ-1P; Tue, 06 Jun 2023 12:13:34 +0000 Received: from muru.com ([72.249.23.125]) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1q6VZ5-001als-1i; Tue, 06 Jun 2023 12:13:32 +0000 Received: from localhost (localhost [127.0.0.1]) by muru.com (Postfix) with ESMTPS id 5D36580AE; Tue, 6 Jun 2023 12:13:26 +0000 (UTC) Date: Tue, 6 Jun 2023 15:13:25 +0300 From: Tony Lindgren To: Chen-Yu Tsai Cc: Greg Kroah-Hartman , Jiri Slaby , Matthias Brugger , John Ogness , AngeloGioacchino Del Regno , linux-serial@vger.kernel.org, linux-mediatek@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] serial: 8250_mtk: Simplify clock sequencing and runtime PM Message-ID: <20230606121325.GB14287@atomide.com> References: <20230606091747.2031168-1-wenst@chromium.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20230606091747.2031168-1-wenst@chromium.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230606_051331_627473_37DB78D5 X-CRM114-Status: GOOD ( 11.72 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org * Chen-Yu Tsai [230606 09:19]: > The 8250_mtk driver's runtime PM support has some issues: > > - The bus clock is enabled (through runtime PM callback) later than a > register write > - runtime PM resume callback directly called in probe, but no > pm_runtime_set_active() call is present > - UART PM function calls the callbacks directly, _and_ calls runtime > PM API > - runtime PM callbacks try to do reference counting, adding yet another > count between runtime PM and clocks > > This fragile setup worked in a way, but broke recently with runtime PM > support added to the serial core. The system would hang when the UART > console was probed and brought up. Great, looks like a good for Linux next to me: Reviewed-by: Tony Lindgren _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel