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Message-ID: <53edd2e5-ffc3-4406-baac-3582edcdbf93@ti.com>
Date:   Mon, 27 Nov 2023 15:10:45 +0530
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Subject: Re: [PATCH v2] iio: adc: ti_am335x_adc: Fix return value check of
 tiadc_request_dma()
Content-Language: en-US
To:     Jonathan Cameron <jic23@kernel.org>,
        Wadim Egorov <w.egorov@phytec.de>
CC:     <lars@metafoo.de>, <robh@kernel.org>, <heiko@sntech.de>,
        <peter.ujfalusi@ti.com>, <mugunthanvnm@ti.com>,
        <linux-iio@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        <nm@ti.com>, <upstream@lists.phytec.de>
References: <20230925134427.214556-1-w.egorov@phytec.de>
 <20231005150917.2d0c833e@jic23-huawei>
From:   Bhavya Kapoor <b-kapoor@ti.com>
In-Reply-To: <20231005150917.2d0c833e@jic23-huawei>
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On 05/10/23 7:39 pm, Jonathan Cameron wrote:
> On Mon, 25 Sep 2023 15:44:27 +0200
> Wadim Egorov <w.egorov@phytec.de> wrote:
>
>> Fix wrong handling of a DMA request where the probing only failed
>> if -EPROPE_DEFER was returned. Instead, let us fail if a non -ENODEV
>> value is returned. This makes DMAs explicitly optional. Even if the
>> DMA request is unsuccessfully, the ADC can still work properly.
>> We do also handle the defer probe case by making use of dev_err_probe().
>>
>> Fixes: f438b9da75eb ("drivers: iio: ti_am335x_adc: add dma support")
>> Signed-off-by: Wadim Egorov <w.egorov@phytec.de>
> +CC Bhavya,
>
> Could you take a look at this given you had comments on v1.
>
> Thanks,
>
> Jonathan

Hi Jonathan, Patch Looks Good To Me and Should now work fine for every case.

Regards

~B-Kapoor

>
>> ---
>> v2:
>>    - Update description
>>    - Drop line break after Fixes tag
>>    - Move decision about optional DMA into probe/caller
>> ---
>>   drivers/iio/adc/ti_am335x_adc.c | 4 +++-
>>   1 file changed, 3 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/iio/adc/ti_am335x_adc.c b/drivers/iio/adc/ti_am335x_adc.c
>> index 8db7a01cb5fb..5f8795986995 100644
>> --- a/drivers/iio/adc/ti_am335x_adc.c
>> +++ b/drivers/iio/adc/ti_am335x_adc.c
>> @@ -670,8 +670,10 @@ static int tiadc_probe(struct platform_device *pdev)
>>   	platform_set_drvdata(pdev, indio_dev);
>>   
>>   	err = tiadc_request_dma(pdev, adc_dev);
>> -	if (err && err == -EPROBE_DEFER)
>> +	if (err && err != -ENODEV) {
>> +		dev_err_probe(&pdev->dev, err, "DMA request failed\n");
>>   		goto err_dma;
>> +	}
>>   
>>   	return 0;
>>