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Date: Wed, 8 May 2024 13:06:36 -0700
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Subject: Re: [PATCH v21 38/39] ASoC: qcom: Populate SoC components string
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To: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>,
        <srinivas.kandagatla@linaro.org>, <mathias.nyman@intel.com>,
        <perex@perex.cz>, <conor+dt@kernel.org>, <corbet@lwn.net>,
        <lgirdwood@gmail.com>, <andersson@kernel.org>, <krzk+dt@kernel.org>,
        <gregkh@linuxfoundation.org>, <Thinh.Nguyen@synopsys.com>,
        <broonie@kernel.org>, <bgoswami@quicinc.com>, <tiwai@suse.com>,
        <bagasdotme@gmail.com>, <robh@kernel.org>, <konrad.dybcio@linaro.org>
CC: <linux-kernel@vger.kernel.org>, <devicetree@vger.kernel.org>,
        <linux-sound@vger.kernel.org>, <linux-usb@vger.kernel.org>,
        <linux-arm-msm@vger.kernel.org>, <linux-doc@vger.kernel.org>,
        <alsa-devel@alsa-project.org>
References: <20240507195116.9464-1-quic_wcheng@quicinc.com>
 <20240507195116.9464-39-quic_wcheng@quicinc.com>
 <cb864ea4-95e3-4e99-920d-341188006291@linux.intel.com>
From: Wesley Cheng <quic_wcheng@quicinc.com>
In-Reply-To: <cb864ea4-95e3-4e99-920d-341188006291@linux.intel.com>
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Hi Pierre,

On 5/7/2024 2:40 PM, Pierre-Louis Bossart wrote:
> 
> 
> On 5/7/24 14:51, Wesley Cheng wrote:
>> For userspace to know about certain capabilities of the current platform
>> card, add tags to the components string that it can use to enable support
>> for that audio path.  In case of USB offloading, the "usboffldplybk: 1" tag
> 
> usboffloadplayback?
> 
> same question as before, do we need spaces?
> 

I think spaces are currently used as a delimiter, so I'll remove the spaces.

> And if we have controls, why do we need component strings? The component
> string is not dynamic to the best of my knowledge, this could be
> problematic if the card is no longer capable of supporting this stream,
> while a control can be updated at will.
> 

Maybe I misunderstood your comment here:

https://lore.kernel.org/linux-usb/925d7c03-c288-49a4-8bcd-395b32810d75@linux.intel.com/

At the time, I didn't include the kcontrols on the USB SND portion of 
it, which was added after this series.  My interpretation was that there 
were userspace entities that could query for general information about 
what the card supports based on the components string, or sound card 
name.  I treated this as an independent identifier, since the change to 
add the offload capable jack was present.

Thanks
Wesley Cheng