RE: [PATCH v3] clk: imx8qxp: Defer instead of failing probe

[Peng Fan]

Hi Diogo,

> Subject: [PATCH v3] clk: imx8qxp: Defer instead of failing probe
> 
> When of_clk_parent_fill is ran without all the parent clocks having
> been probed then the probe function will return -EINVAL, making it so
> that the probe isn't attempted again. As fw_devlink is on by default
> this does not usually happen, but if fw_devlink is disabled then it is
> very possible that the parent clock will be probed after the lpcg first
> attempt.

Did you meet issue with fw_devlink disabled?

> 
> Signed-off-by: Diogo Silva <diogo.pais@xxxxxxxxxxxxx>
> ---
> v2: change from dev_warn to dev_err_probe
> v3: refresh patch
> ---
>  drivers/clk/imx/clk-imx8qxp-lpcg.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/clk/imx/clk-imx8qxp-lpcg.c b/drivers/clk/imx/clk-
> imx8qxp-lpcg.c
> index d0ccaa040225..cae8f6060fe8 100644
> --- a/drivers/clk/imx/clk-imx8qxp-lpcg.c
> +++ b/drivers/clk/imx/clk-imx8qxp-lpcg.c
> @@ -225,8 +225,8 @@ static int imx_lpcg_parse_clks_from_dt(struct
> platform_device *pdev,
> 
>         ret = of_clk_parent_fill(np, parent_names, count);
>         if (ret != count) {
> -               dev_err(&pdev->dev, "failed to get clock parent names\n");
> -               return count;
> +               return dev_err_probe(&pdev->dev, -EPROBE_DEFER,
> +                                    "failed to get all clock parent
> + names\n");
>         }

The change is not enough, you also need to handle
        ret = imx_lpcg_parse_clks_from_dt(pdev, np);                                                
        if (!ret)                                                                                   
                return 0;
->
        ret = imx_lpcg_parse_clks_from_dt(pdev, np);                                                
        if (!ret)                                                                                   
                return 0;
        if (ret == -EPROBE_DEFER)
                return ret;

Regards,
Peng.

> 
>         ret = of_property_read_string_array(np, "clock-output-names",
> --
> 2.34.1
> ________________________________________
> From: Abel Vesa <abel.vesa@xxxxxxxxxx>
> Sent: Wednesday, August 28, 2024 10:31 AM
> To: Diogo Manuel Pais Silva
> Cc: Peng Fan; abelvesa@xxxxxxxxxx; linux-clk@xxxxxxxxxxxxxxx;
> shawnguo@xxxxxxxxxx; kernel@xxxxxxxxxxxxxx;
> s.hauer@xxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx;
> sboyd@xxxxxxxxxx; mturquette@xxxxxxxxxxxx; festevam@xxxxxxxxx;
> imx@xxxxxxxxxxxxxxx; EMC: linux-kernel@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH v2] clk: imx8qxp: Defer instead of failing probe
> 
> On 24-07-02 08:10:44, Diogo Manuel Pais Silva wrote:
> > When of_clk_parent_fill is ran without all the parent clocks having
> been probed then the probe function will return -EINVAL, making it so
> that the probe isn't attempted again. As fw_devlink is on by default
> this does not usually happen, but if fw_devlink is disabled then it is
> very possible that the parent clock will be probed after the lpcg first
> attempt.
> >
> > Signed-off-by: Diogo Silva <diogo.pais@xxxxxxxxxxxxx>
> 
> This patch doesn't apply cleanly.
> 
> Please respin.
> 
> Thanks!
> 
> > ---
> > v2: change from dev_warn to dev_err_probe
> > ---
> >  drivers/clk/imx/clk-imx8qxp-lpcg.c | 4 ++--
> >  1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/clk/imx/clk-imx8qxp-lpcg.c
> > b/drivers/clk/imx/clk-imx8qxp-lpcg.c
> > index d0ccaa040225..7bd9b745edbe 100644
> > --- a/drivers/clk/imx/clk-imx8qxp-lpcg.c
> > +++ b/drivers/clk/imx/clk-imx8qxp-lpcg.c
> > @@ -225,8 +225,8 @@ static int
> imx_lpcg_parse_clks_from_dt(struct
> > platform_device *pdev,
> >
> >       ret = of_clk_parent_fill(np, parent_names, count);
> >       if (ret != count) {
> > -             dev_err(&pdev->dev, "failed to get clock parent names\n");
> > -             return count;
> > +             return dev_err_probe(&pdev->dev, -EPROBE_DEFER,
> > +                             "failed to get all clock parent
> > + names\n");
> >       }
> >
> >       ret = of_property_read_string_array(np, "clock-output-names",
> > --
> > 2.34.1
> CONFIDENTIALITY: The contents of this e-mail are confidential and
> intended only for the above addressee(s). If you are not the intended
> recipient, or the person responsible for delivering it to the intended
> recipient, copying or delivering it to anyone else or using it in any
> unauthorized manner is prohibited and may be unlawful. If you receive
> this e-mail by mistake, please notify the sender and the systems
> administrator at straymail@xxxxxxxxxx immediately.