2022-04-23 17:12:14

by Bjorn Andersson

[permalink] [raw]
Subject: Re: [PATCH v2 1/5] scsi: ufs: qcom: Fix acquiring the optional reset control line

On Sat 23 Apr 07:02 PDT 2022, Manivannan Sadhasivam wrote:

> On Qcom UFS platforms, the reset control line seems to be optional
> (for SoCs like MSM8996 and probably for others too). The current logic
> tries to mimic the `devm_reset_control_get_optional()` API but it also
> continues the probe if there is an error with the declared reset line in
> DT/ACPI.
>
> In an ideal case, if the reset line is not declared in DT/ACPI, the probe
> should continue. But if there is problem in acquiring the declared reset
> line (like EPROBE_DEFER) it should fail and return the appropriate error
> code.
>
> Signed-off-by: Manivannan Sadhasivam <[email protected]>
> ---
> drivers/scsi/ufs/ufs-qcom.c | 10 +++++-----
> 1 file changed, 5 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/scsi/ufs/ufs-qcom.c b/drivers/scsi/ufs/ufs-qcom.c
> index 0d2e950d0865..bee81b45299e 100644
> --- a/drivers/scsi/ufs/ufs-qcom.c
> +++ b/drivers/scsi/ufs/ufs-qcom.c
> @@ -1002,13 +1002,13 @@ static int ufs_qcom_init(struct ufs_hba *hba)
> host->hba = hba;
> ufshcd_set_variant(hba, host);
>
> - /* Setup the reset control of HCI */
> - host->core_reset = devm_reset_control_get(hba->dev, "rst");
> + /* Setup the optional reset control of HCI */
> + host->core_reset = devm_reset_control_get_optional(hba->dev, "rst");
> if (IS_ERR(host->core_reset)) {
> err = PTR_ERR(host->core_reset);
> - dev_warn(dev, "Failed to get reset control %d\n", err);
> - host->core_reset = NULL;
> - err = 0;
> + if (err != -EPROBE_DEFER)

dev_err_probe() does this comparison internally, so you can omit it
here.

With that removed, feel free to add my:
Reviewed-by: Bjorn Andersson <[email protected]>

Regards,
Bjorn

> + dev_err_probe(dev, err, "Failed to get reset control\n");
> + goto out_variant_clear;
> }
>
> /* Fire up the reset controller. Failure here is non-fatal. */
> --
> 2.25.1
>


2022-04-26 10:28:27

by Andrew Halaney

[permalink] [raw]
Subject: Re: [PATCH v2 1/5] scsi: ufs: qcom: Fix acquiring the optional reset control line

On Sat, Apr 23, 2022 at 07:59:17AM -0700, Bjorn Andersson wrote:
> On Sat 23 Apr 07:02 PDT 2022, Manivannan Sadhasivam wrote:
>
> > On Qcom UFS platforms, the reset control line seems to be optional
> > (for SoCs like MSM8996 and probably for others too). The current logic
> > tries to mimic the `devm_reset_control_get_optional()` API but it also
> > continues the probe if there is an error with the declared reset line in
> > DT/ACPI.
> >
> > In an ideal case, if the reset line is not declared in DT/ACPI, the probe
> > should continue. But if there is problem in acquiring the declared reset
> > line (like EPROBE_DEFER) it should fail and return the appropriate error
> > code.
> >
> > Signed-off-by: Manivannan Sadhasivam <[email protected]>
> > ---
> > drivers/scsi/ufs/ufs-qcom.c | 10 +++++-----
> > 1 file changed, 5 insertions(+), 5 deletions(-)
> >
> > diff --git a/drivers/scsi/ufs/ufs-qcom.c b/drivers/scsi/ufs/ufs-qcom.c
> > index 0d2e950d0865..bee81b45299e 100644
> > --- a/drivers/scsi/ufs/ufs-qcom.c
> > +++ b/drivers/scsi/ufs/ufs-qcom.c
> > @@ -1002,13 +1002,13 @@ static int ufs_qcom_init(struct ufs_hba *hba)
> > host->hba = hba;
> > ufshcd_set_variant(hba, host);
> >
> > - /* Setup the reset control of HCI */
> > - host->core_reset = devm_reset_control_get(hba->dev, "rst");
> > + /* Setup the optional reset control of HCI */
> > + host->core_reset = devm_reset_control_get_optional(hba->dev, "rst");
> > if (IS_ERR(host->core_reset)) {
> > err = PTR_ERR(host->core_reset);
> > - dev_warn(dev, "Failed to get reset control %d\n", err);
> > - host->core_reset = NULL;
> > - err = 0;
> > + if (err != -EPROBE_DEFER)
>
> dev_err_probe() does this comparison internally, so you can omit it
> here.
>
> With that removed, feel free to add my:
> Reviewed-by: Bjorn Andersson <[email protected]>
>
> Regards,
> Bjorn

+1; well with that change in place:
Reviewed-by: Andrew Halaney <[email protected]>

Thanks,
Andrew

>
> > + dev_err_probe(dev, err, "Failed to get reset control\n");
> > + goto out_variant_clear;
> > }
> >
> > /* Fire up the reset controller. Failure here is non-fatal. */
> > --
> > 2.25.1
> >
>