Message-ID: <9a05953e-fc43-3223-2c96-8e12eac93bf4@suse.com>
Date:   Thu, 9 Mar 2023 12:32:48 +0100
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Subject: Re: [PATCH v3 27/28] sound: usb: card: Allow for rediscovery of
 connected USB SND devices
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To:     Wesley Cheng <quic_wcheng@quicinc.com>,
        srinivas.kandagatla@linaro.org, mathias.nyman@intel.com,
        perex@perex.cz, broonie@kernel.org, lgirdwood@gmail.com,
        krzysztof.kozlowski+dt@linaro.org, agross@kernel.org,
        Thinh.Nguyen@synopsys.com, bgoswami@quicinc.com,
        andersson@kernel.org, robh+dt@kernel.org,
        gregkh@linuxfoundation.org, tiwai@suse.com
Cc:     linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org,
        alsa-devel@alsa-project.org, devicetree@vger.kernel.org,
        linux-usb@vger.kernel.org, quic_jackp@quicinc.com,
        quic_plai@quicinc.com
References: <20230308235751.495-1-quic_wcheng@quicinc.com>
 <20230308235751.495-28-quic_wcheng@quicinc.com>
From:   Oliver Neukum <oneukum@suse.com>
In-Reply-To: <20230308235751.495-28-quic_wcheng@quicinc.com>
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On 09.03.23 00:57, Wesley Cheng wrote:
  
> +/*
> + * in case the platform driver was not ready at the time of USB SND
> + * device connect, expose an API to discover all connected USB devices
> + * so it can populate any dependent resources/structures.
> + */
> +void snd_usb_rediscover_devices(void)
> +{
> +	int i;
> +
> +	mutex_lock(&register_mutex);
> +	for (i = 0; i < SNDRV_CARDS; i++) {
> +		if (usb_chip[i])
> +			if (platform_ops && platform_ops->connect_cb)

Really check this every time?

	Regards
		Oliver