Message-ID: <e1291152-2c74-514c-00a5-526564d7d827@linaro.org>
Date:   Thu, 26 Jan 2023 16:35:50 +0000
MIME-Version: 1.0
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101
 Thunderbird/102.4.2
Subject: Re: [RFC PATCH v2 11/22] ASoC: qcom: Add USB backend ASoC driver for
 Q6
To:     Wesley Cheng <quic_wcheng@quicinc.com>, 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:     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: <20230126031424.14582-1-quic_wcheng@quicinc.com>
 <20230126031424.14582-12-quic_wcheng@quicinc.com>
Content-Language: en-US
From:   Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
In-Reply-To: <20230126031424.14582-12-quic_wcheng@quicinc.com>
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 7bit
Precedence: bulk


On 26/01/2023 03:14, Wesley Cheng wrote:
> +}
> +
> +static int q6usb_dai_dev_probe(struct platform_device *pdev)
> +{
...
> +	data->priv.domain = iommu_domain_alloc(pdev->dev.bus);
> +	if (!data->priv.domain) {
> +		dev_err(&pdev->dev, "failed to allocate iommu domain\n");
> +		return -ENODEV;
> +	}
> +
> +	/* attach to external processor iommu */
> +	ret = iommu_attach_device(data->priv.domain, &pdev->dev);
> +	if (ret) {
> +		dev_err(&pdev->dev, "failed to attach device ret = %d\n", ret);
> +		goto free_domain;
> +	}
> +
Why are we doing this manually here? device core should take care of 
attaching iommu to the device instance.

...


> +detach_device:
> +	iommu_detach_device(data->priv.domain, &pdev->dev);
> +free_domain:
> +	iommu_domain_free(data->priv.domain);
> +
> +	return ret;
> +}
> +
> +static int q6usb_dai_dev_remove(struct platform_device *pdev)
> +{
> +	struct q6usb_port_data *data = platform_get_drvdata(pdev);
> +
> +	iommu_detach_device(data->priv.domain, &pdev->dev);
> +	iommu_domain_free(data->priv.domain);
> +