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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=no 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 3F8E0C33C9E for ; Thu, 30 Jan 2020 10:47:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1ACA0206D3 for ; Thu, 30 Jan 2020 10:47:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726885AbgA3KrU convert rfc822-to-8bit (ORCPT ); Thu, 30 Jan 2020 05:47:20 -0500 Received: from mail-oi1-f193.google.com ([209.85.167.193]:44305 "EHLO mail-oi1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726873AbgA3KrU (ORCPT ); Thu, 30 Jan 2020 05:47:20 -0500 Received: by mail-oi1-f193.google.com with SMTP id d62so2990447oia.11; Thu, 30 Jan 2020 02:47:18 -0800 (PST) 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:content-transfer-encoding; bh=bPds3H999b4sbHrI2xdAWDEqcLze26VG68J4dxk2Yzk=; b=hMJEGbqCGoXqKSMm7XRaHGmbjlgrwgA35iGbJ6tjlpXkjSz9HM5pUHHn8ZIiiHeeLe 2Lnhbyqpw+Kb4JkIdM0qHToDd85qVJ74mIho77RoWzEXha+ZabgI7sQ+ZQZGD9ueR0dc o9k+GGWM5kOd9qDV/fH92l9MF0QHEmejEGBcJCcszmMeZh80CQTVDt9jtjgbS8QYY3or RkfExkDASbxI10MM3qf4Z+Q+HK7c/BuegdFSB87HbsNB4nP1XQXxtexFG1AZ5CEZiYFH cIPlB6BSsVlvTHd8O5zJ5GS0wHqQDSTsFim6TYB318kTYV8LiE3Zm8JDFjYd9iWH4gF2 ZtIQ== X-Gm-Message-State: APjAAAW2hfsMAlsVDdNYmMVVWbSgEEe4z3wQ0PKacILSF//G5ty5OCMB NtfdQXhJaCY7uehkiwAXKNzW55U/KWzJYh6KNEY= X-Google-Smtp-Source: APXvYqxIIIUZohrSHPenmUgXJVSQveonFR4aBuAgIfsx5KeWWKf4XoO8s9HK9UDm6Zq9rBqeQiGzkmicCj+rhBlMZPs= X-Received: by 2002:aca:48cd:: with SMTP id v196mr2530305oia.102.1580381238139; Thu, 30 Jan 2020 02:47:18 -0800 (PST) MIME-Version: 1.0 References: <20200117153056.31363-1-geert+renesas@glider.be> In-Reply-To: From: Geert Uytterhoeven Date: Thu, 30 Jan 2020 11:47:06 +0100 Message-ID: Subject: Re: [PATCH v2] dmaengine: Create symlinks between DMA channels and slaves To: Marek Szyprowski Cc: Geert Uytterhoeven , Vinod Koul , Dan Williams , dmaengine@vger.kernel.org, Linux-Renesas , Linux Kernel Mailing List Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT Sender: dmaengine-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org Hi Marek, On Thu, Jan 30, 2020 at 11:33 AM Marek Szyprowski wrote: > On 30.01.2020 09:30, Geert Uytterhoeven wrote: > > On Wed, Jan 29, 2020 at 6:47 PM Marek Szyprowski > > wrote: > >> On 17.01.2020 16:30, Geert Uytterhoeven wrote: > >>> Currently it is not easy to find out which DMA channels are in use, and > >>> which slave devices are using which channels. > >>> > >>> Fix this by creating two symlinks between the DMA channel and the actual > >>> slave device when a channel is requested: > >>> 1. A "slave" symlink from DMA channel to slave device, > >>> 2. A "dma:" symlink slave device to DMA channel. > >>> When the channel is released, the symlinks are removed again. > >>> The latter requires keeping track of the slave device and the channel > >>> name in the dma_chan structure. > >>> > >>> Note that this is limited to channel request functions for requesting an > >>> exclusive slave channel that take a device pointer (dma_request_chan() > >>> and dma_request_slave_channel*()). > >>> > >>> Signed-off-by: Geert Uytterhoeven > >>> Tested-by: Niklas Söderlund > >> This patch breaks booting on almost all Exynos based boards: > >> > >> https://lore.kernel.org/linux-samsung-soc/20200129161113.GE3928@sirena.org.uk/T/#u > > Sorry for the breakage. > > No problem, that's why we have linux-next. Not really: by that time it had been upstream for 2 days :-( Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds