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=-0.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,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 8780FCA9ED3 for ; Mon, 4 Nov 2019 08:27:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5A1CB222CE for ; Mon, 4 Nov 2019 08:27:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="W9kqiDQ9" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727320AbfKDI1W (ORCPT ); Mon, 4 Nov 2019 03:27:22 -0500 Received: from mail-il1-f194.google.com ([209.85.166.194]:43551 "EHLO mail-il1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726100AbfKDI1W (ORCPT ); Mon, 4 Nov 2019 03:27:22 -0500 Received: by mail-il1-f194.google.com with SMTP id j2so11871366ilc.10; Mon, 04 Nov 2019 00:27:22 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc; bh=HX4pBaoGeNQiQ+yt/czMAU0I4DAG8i9or/oZi9FPxrA=; b=W9kqiDQ9H6TBYA6EcpFgXwkd1ww7ZKsT2zyowkzPMfKN4YVvECqYHFNqcisKcs65Kk q5u5OPB/FgY9l1YV1ZSKIUBi3rPU9yIYTDQuCkSZbGymlKTuB2FEviFyZWugv98foIPI 3x9QkmCNURX4PfLY/HJ1CUUuYZvmQxH5YuPrJ9Aqe/SqFCYweQn84SL9R17UI5R8f5Lx 1w41qnyT3bMi/5NVlEwuLKRFhng03Ho7Hv1RrClIIepNa6dFYP5ePuUS3Fdc4rhOzmrE 6944AZzIB5M88aKEDACrSUhxtzbdFw6bf7eVXi0c13JkVKXTQJaWqDZde9NYVcjvsI4t 69Bg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=HX4pBaoGeNQiQ+yt/czMAU0I4DAG8i9or/oZi9FPxrA=; b=Gsih8xBpzdbte0YP93AioRbdN07c1u+urcm79VOehTEdCZn0ckEfRVTHQKCPmxiKcT qLUma1wnicWu9lXHJPNgcEoeMNtjMrF+lA9OqeZ2KenBql/qBHRVxLx7Gkyz88ztVig9 JBNF4KxwVL65FRYbDN5k/Au2I4p9OBgHZPU7KyhTdcyt639JQdC++o5c65frypx8+ELu /Sl2YV2NfoGvsFubnpsB1AikvFu49FEmDeZGKNa+rtqY5BRIOA5YCZNniuVzm8xE+iLq OR0zmcDDeTIfLeLtCJ0p2Zb1W6Etbew+xbzm8CGHnsWGRC/eGheOV2Msw3Yblg5o2+mN 8fQQ== X-Gm-Message-State: APjAAAVmVHbU+GM8warlUAJMbw9bc0D9qeG1iEsaDTWHl71JNj6xyqjL 2tzg2oDvXOR33IlO7MLFAIwkqEb1EdLqej2bD8E= X-Google-Smtp-Source: APXvYqyuDJikbS+1zmxs0fj3VNP0HAfX0NYxrm42A9cOVaQnPX48CUpkmsJ+WiHDhDI/Wl8EF5mvTyRVDLJGe7oNJhI= X-Received: by 2002:a92:b00f:: with SMTP id x15mr26048913ilh.280.1572856041383; Mon, 04 Nov 2019 00:27:21 -0800 (PST) MIME-Version: 1.0 Received: by 2002:ad5:4348:0:0:0:0:0 with HTTP; Mon, 4 Nov 2019 00:27:20 -0800 (PST) In-Reply-To: References: From: youling 257 Date: Mon, 4 Nov 2019 16:27:20 +0800 Message-ID: Subject: Re: ALSA: pcm: use dma_can_mmap() to check if a device supports dma_mmap_* To: Takashi Iwai Cc: linux-xtensa@linux-xtensa.org, Michal Simek , Vladimir Murzin , linux-parisc@vger.kernel.org, linux-sh@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, Helge Deller , x86@kernel.org, Linux Kernel Mailing List , linux-m68k@lists.linux-m68k.org, Robin Murphy , linux-arm-kernel@lists.infradead.org, hch@lst.de, gregkh@google.com Content-Type: text/plain; charset="UTF-8" Sender: linux-parisc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-parisc@vger.kernel.org This driver https://android.googlesource.com/kernel/common/+/refs/heads/android-mainline/drivers/usb/gadget/function/f_audio_source.c 2019-11-04 16:02 GMT+08:00, Takashi Iwai : > Exactly which driver is hit? The code path is via hw_support_mmap() > and it's currently: > > static bool hw_support_mmap(struct snd_pcm_substream *substream) > { > if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_MMAP)) > return false; > > if (substream->ops->mmap || > substream->dma_buffer.dev.type != SNDRV_DMA_TYPE_DEV) > return true; > > return dma_can_mmap(substream->dma_buffer.dev.dev); > } > > so at least the driver has already set the SNDRV_DMA_TYPE_DEV > explicitly (it's non-zero) and some device object, but the device > object was invalid for dma_can_mmap() call. > > This smells more like a driver-side issue, not in the core side. > > > thanks, > > Takashi >