Re: [PATCH 5/9] i2c: qcom-cci: Use dev_err_probe in probe function

[Dmitry Baryshkov <dmitry.baryshkov@linaro.org>]

On Mon, 21 Aug 2023 at 23:39, Harshit Mogalapalli
<harshit.m.mogalapalli@oracle.com> wrote:
>
> Hi,
>
> On 18/08/23 4:36 pm, Dmitry Baryshkov wrote:
> > On 28/07/2023 04:31, 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@huawei.com>
> >> ---
> >>   drivers/i2c/busses/i2c-qcom-cci.c | 6 ++----
> >>   1 file changed, 2 insertions(+), 4 deletions(-)
> >
> > Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> >
> >>
> >> diff --git a/drivers/i2c/busses/i2c-qcom-cci.c
> >> b/drivers/i2c/busses/i2c-qcom-cci.c
> >> index 622dc14add9d..cf13abec05f1 100644
> >> --- a/drivers/i2c/busses/i2c-qcom-cci.c
> >> +++ b/drivers/i2c/busses/i2c-qcom-cci.c
> >> @@ -588,10 +588,8 @@ static int cci_probe(struct platform_device *pdev)
> >>       /* Clocks */
> >>       ret = devm_clk_bulk_get_all(dev, &cci->clocks);
> >> -    if (ret < 1) {
> >> -        dev_err(dev, "failed to get clocks %d\n", ret);
> >> -        return ret;
> >> -    }
> >> +    if (ret < 1)
> >> +        return dev_err_probe(dev, ret, "failed to get clocks\n");
>
> Description:
> -----------
>   * devm_clk_bulk_get_all - managed get multiple clk consumers
>   * @dev: device for clock "consumer"
>   * @clks: pointer to the clk_bulk_data table of consumer
>   *
>   * Returns a positive value for the number of clocks obtained while the
>   * clock references are stored in the clk_bulk_data table in @clks field.
>   * Returns 0 if there're none and a negative value if something failed.
> -----------
>
> When ret = 0;
>
> "zero" is passed to dev_err_probe and we are returning success(zero)
> from probe function.
>
> Based on other instances of devm_clk_bulk_get_all() API, can we fix it
> by changing condition like this?
>
> diff --git a/drivers/i2c/busses/i2c-qcom-cci.c
> b/drivers/i2c/busses/i2c-qcom-cci.c
> index cf13abec05f1..cea6f70d2b8d 100644
> --- a/drivers/i2c/busses/i2c-qcom-cci.c
> +++ b/drivers/i2c/busses/i2c-qcom-cci.c
> @@ -588,7 +588,7 @@ static int cci_probe(struct platform_device *pdev)
>          /* Clocks */
>
>          ret = devm_clk_bulk_get_all(dev, &cci->clocks);
> -       if (ret < 1)
> +       if (ret < 0)
>                  return dev_err_probe(dev, ret, "failed to get clocks\n");

Only if it succeeded with something like:

if (!ret)
    return dev_err_probe(dev, -EINVAL, "Not enough clocks in DT\n");

But it is a separate topic and should be a part of the separate patch.

>          cci->nclocks = ret;
>
>
> Thanks,
> Harshit
>
> >>       cci->nclocks = ret;
> >>       /* Retrieve CCI clock rate */
> >



-- 
With best wishes
Dmitry