Message-ID: <ad9e375e-fe4f-b4bd-aebd-26f5f0a6317b@linux.intel.com>
Date:   Thu, 26 Jan 2023 10:22:56 -0600
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From:   Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Subject: Re: [RFC PATCH v2 00/22] Introduce QC USB SND audio offloading
 support
To:     Wesley Cheng <quic_wcheng@quicinc.com>,
        srinivas.kandagatla@linaro.org, mathias.nyman@intel.com,
        perex@perex.cz, lgirdwood@gmail.com, andersson@kernel.org,
        krzysztof.kozlowski+dt@linaro.org, gregkh@linuxfoundation.org,
        Thinh.Nguyen@synopsys.com, broonie@kernel.org,
        bgoswami@quicinc.com, tiwai@suse.com, robh+dt@kernel.org,
        agross@kernel.org
Cc:     devicetree@vger.kernel.org, alsa-devel@alsa-project.org,
        linux-arm-msm@vger.kernel.org, linux-usb@vger.kernel.org,
        linux-kernel@vger.kernel.org, quic_jackp@quicinc.com,
        quic_plai@quicinc.com
References: <20230126031424.14582-1-quic_wcheng@quicinc.com>
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In-Reply-To: <20230126031424.14582-1-quic_wcheng@quicinc.com>
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This version has lots of improvements, but I am concerned
about hard-coded ops/callbacks that look racy and assume dependencies
between driver probes. How does this work if the probe is delayed on one
side for some reason? What happens is a driver is 'blacklisted' and
manually added later? The code has to deal with this sort of known unknowns.

I also still have a bit of heartburn with the notion that there would be
a completely separate card with all the control for volume/mute/etc
having to be duplicated.

It's still a lot of good work so thanks for sharing and pushing for this
capability.