Re: [PATCH] ACPI: nfit: adjust annotation for why return 0 if fail to find NFIT at startup

From: Verma, Vishal L
Date: Tue Aug 07 2018 - 15:25:20 EST



On Tue, 2018-08-07 at 02:15 -0400, Ocean He wrote:
> From: Ocean He <hehy1@xxxxxxxxxx>

Just some minor nits in commit message wording:

>
> Add detail explanation why it's ok to return 0 if fail to find NFIT at
detailed ^for ^we ^an
> startup, refer to chapter 9.20.2 NVDIMM Root Device in ACPI 6.2 spec.
. Refer

Perhaps Dave can fixup while applying..
>
> Signed-off-by: Ocean He <hehy1@xxxxxxxxxx>
> ---
> v1: https://lists.01.org/pipermail/linux-nvdimm/2018-August/017311.html
> v2: Per Vishal's comments of v1, it turns out that it's right to keep
> "return 0" if NFIT not found at boot time. This v2 adjust annotation
> to avoid misunderstanding of "return 0".

Looks good, thanks for the update. Feel free to add:
Reviewed-by: Vishal Verma <vishal.l.verma@xxxxxxxxx>

>
> drivers/acpi/nfit/core.c | 8 +++++++-
> 1 file changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c
> index 7c47900..1b982fe 100644
> --- a/drivers/acpi/nfit/core.c
> +++ b/drivers/acpi/nfit/core.c
> @@ -3353,7 +3353,13 @@ static int acpi_nfit_add(struct acpi_device *adev)
>
> status = acpi_get_table(ACPI_SIG_NFIT, 0, &tbl);
> if (ACPI_FAILURE(status)) {
> - /* This is ok, we could have an nvdimm hotplugged later */
> + /* The NVDIMM root device allows OS to trigger enumeration of
> + * NVDIMMs through NFIT at boot time and re-enumeration at
> + * root level via the _FIT method during runtime.
> + * This is ok to return 0 here, we could have an nvdimm
> + * hotplugged later and evaluate _FIT method which returns
> + * data in the format of a series of NFIT Structures.
> + */
> dev_dbg(dev, "failed to find NFIT at startup\n");
> return 0;
> }