Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932662AbbHGQUw (ORCPT ); Fri, 7 Aug 2015 12:20:52 -0400 Received: from www.linutronix.de ([62.245.132.108]:51158 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932319AbbHGQUu (ORCPT ); Fri, 7 Aug 2015 12:20:50 -0400 Message-ID: <55C4DADC.9070004@linutronix.de> Date: Fri, 07 Aug 2015 18:20:44 +0200 From: Sebastian Andrzej Siewior User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Icedove/31.7.0 MIME-Version: 1.0 To: Peter Hurley , Russell King - ARM Linux CC: Peter Ujfalusi , Vinod Koul , Dan Williams , dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org, nsekhar@ti.com, linux-omap@vger.kernel.org, linux-serial@vger.kernel.org, john.ogness@linutronix.de, Greg KH Subject: Re: [PATCH] dma: omap-dma: add support for pause of non-cyclic transfers References: <1438936917-7254-1-git-send-email-bigeasy@linutronix.de> <55C47DE1.9020902@ti.com> <55C48A1E.3070007@linutronix.de> <20150807132241.GN7576@n2100.arm.linux.org.uk> <55C4B5AE.10309@linutronix.de> <20150807135727.GP7576@n2100.arm.linux.org.uk> <55C4CA00.3060206@hurleysoftware.com> <20150807152939.GQ7576@n2100.arm.linux.org.uk> <55C4D7AF.8060305@hurleysoftware.com> In-Reply-To: <55C4D7AF.8060305@hurleysoftware.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1090 Lines: 26 On 08/07/2015 06:07 PM, Peter Hurley wrote: >> If we look at what 8250-dma.c is doing: >> >> if (dma->rx_running) { >> dmaengine_pause(dma->rxchan); >> >> It's 8250-dma.c which is silently _ignoring_ the return code, failing >> to check that the operation it requested worked. Maybe this should be >> WARN_ON(dmaengine_pause(dma->rxchan)) or at least it should print a >> message? > > Thanks for the suggestion; I'll hold on to that and push it after we add > the 8250 omap dma pause in mainline. I have a patch ready with WARN_ON_ONCE() for 8250-omap and 8250-dma. This warning would trigger on am335x/edma until v4.2-rc1 and omap-dma based version is open. I could post it if you want me to. Besides that those two, there are four other drivers ignoring the return code dmaengine_pause(). Sebastian -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/