[PATCH 8/9] i2c: imx-lpi2c: Use dev_err_probe in probe function

Liao, Chang liaochang1 at huawei.com
Mon Aug 7 03:44:23 PDT 2023


Hi, Andi

在 2023/8/7 16:17, Andi Shyti 写道:
> On Mon, Aug 07, 2023 at 10:13:30AM +0800, Liao, Chang wrote:
>> Hi, Andi
>>
>> 在 2023/8/5 6:16, Andi Shyti 写道:
>>> On Wed, Aug 02, 2023 at 05:57:36PM +0800, Liao Chang wrote:
>>>> Use the dev_err_probe function instead of dev_err in the probe function
>>>> so that the printed messge includes the return value and also handles
>>>> -EPROBE_DEFER nicely.
>>>>
>>>> Signed-off-by: Liao Chang <liaochang1 at huawei.com>
>>>> ---
>>>>  drivers/i2c/busses/i2c-imx-lpi2c.c | 12 ++++--------
>>>>  1 file changed, 4 insertions(+), 8 deletions(-)
>>>>
>>>> diff --git a/drivers/i2c/busses/i2c-imx-lpi2c.c b/drivers/i2c/busses/i2c-imx-lpi2c.c
>>>> index c3287c887c6f..bfa788b3775b 100644
>>>> --- a/drivers/i2c/busses/i2c-imx-lpi2c.c
>>>> +++ b/drivers/i2c/busses/i2c-imx-lpi2c.c
>>>> @@ -569,10 +569,8 @@ static int lpi2c_imx_probe(struct platform_device *pdev)
>>>>  		sizeof(lpi2c_imx->adapter.name));
>>>>  
>>>>  	ret = devm_clk_bulk_get_all(&pdev->dev, &lpi2c_imx->clks);
>>>> -	if (ret < 0) {
>>>> -		dev_err(&pdev->dev, "can't get I2C peripheral clock, ret=%d\n", ret);
>>>> -		return ret;
>>>> -	}
>>>> +	if (ret < 0)
>>>> +		return dev_err_probe(&pdev->dev, ret, "can't get I2C peripheral clock\n");
>>>
>>> you cut on this because the line was going over 100 characters? :)
>>>
>>> In theory you shouldn't change the print message when doing such
>>> changes and you can still split it as:
>>>
>>> 		return dev_err_probe(&pdev->dev, ret,
>>> 				     "can't get I2C peripheral clock, ret=%d\n",
>>> 				     ret);
>>>
>>> and you're even within the 80 characters.
>>
>> Since dev_err_probe always print the second parameter that happens to be the return value,
>> I remove the "ret=%d" from the original message to avoid a redundant error message.
>>
>> So is it better to keep the original message unchanged, even though dev_err_probe also prints
>> the return error value? Or is it better to make this change so that all error messages printed
>> in the probe function include the return value in a consistent style?
> 
> yes, you are right! Then please ignore this comment, but...
> 
>>>   	ret = devm_request_irq(&pdev->dev, irq, lpi2c_imx_isr, 0,
>>>   		pdev->name, lpi2c_imx);
>>> - 	if (ret) {
>>> - 		dev_err(&pdev->dev, "can't claim irq %d\n", irq);
>>> - 		return ret;
>>> - 	}
>>> + 	if (ret)
>>> + 		return dev_err_probe(&pdev->dev, ret, "can't claim irq %d\n", irq);
> 
> please make it coherent to this second part, as well, where the
> error number is printed.

Do you mean to convert it to the following?

    if (ret)
        return dev_err_probe(&pdev->dev, ret, "can't claim irq\n");

I understand that the style of error message printed by dev_err_probe is like
"error [ERRNO]: [customized message]", the [ERRNO] comes from 2nd parameter,
[customized message] comes from 3rd paramter, if the original [customized message]it
also print ERRNO, i intend to remove it in this patch, otherwise, I will just keep it.
In the above code, [customized message] intend to print irq but return value, so it is
better to keep the original message, right?

Thanks.

> 
> Thank you,
> Andi

-- 
BR
Liao, Chang



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