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Date:   Wed, 02 Mar 2022 09:27:45 +0100
Message-ID: <s5hsfs0oj26.wl-tiwai@suse.de>
From:   Takashi Iwai <tiwai@suse.de>
To:     Zhen Ni <nizhen@uniontech.com>
Cc:     perex@perex.cz, tiwai@suse.com, alsa-devel@alsa-project.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] ALSA: intel_hdmi: Fix reference to PCM buffer address
In-Reply-To: <20220302074241.30469-1-nizhen@uniontech.com>
References: <20220302074241.30469-1-nizhen@uniontech.com>
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On Wed, 02 Mar 2022 08:42:41 +0100,
Zhen Ni wrote:
> 
> PCM buffers might be allocated dynamically when the buffer
> preallocation failed or a larger buffer is requested, and it's not
> guaranteed that substream->dma_buffer points to the actually used
> buffer.  The driver needs to refer to substream->runtime->dma_addr
> instead for the buffer address.
> 
> Signed-off-by: Zhen Ni <nizhen@uniontech.com>

Thanks, applied now with Cc-to-stable.

I guess the had_pcm_mmap() can be dropped completely and replaced with
the standard mmap helper, as what we really want is rather wc.
But it can be done for 5.18.


Takashi