Re: [PATCH v4 1/4] ufs: core: Remove redundant wb check

[Bean Huo]

On 08.12.22 12:31 AM, Bart Van Assche wrote:
> On 11/27/22 04:08, Arthur Simchaev wrote:
> > We used to use the extended-feature field in the device descriptor,
> > as an indication that the device supports ufs2.2 or later.
> > Remove that as this check is specifically done few lines above.
> >
> > Reviewed-by: Bean Huo <beanhuo@xxxxxxxxxx>
> > Signed-off-by: Arthur Simchaev <Arthur.Simchaev@xxxxxxx>
> > ---
> >   drivers/ufs/core/ufshcd.c | 4 ----
> >   1 file changed, 4 deletions(-)
> >
> > diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
> > index 2dbe249..2e47c69 100644
> > --- a/drivers/ufs/core/ufshcd.c
> > +++ b/drivers/ufs/core/ufshcd.c
> > @@ -7608,10 +7608,6 @@ static void ufshcd_wb_probe(struct ufs_hba 
> > *hba, const u8 *desc_buf)
> >            (hba->dev_quirks & 
> > UFS_DEVICE_QUIRK_SUPPORT_EXTENDED_FEATURES)))
> >           goto wb_disabled;
> >   -    if (hba->desc_size[QUERY_DESC_IDN_DEVICE] <
> > -        DEVICE_DESC_PARAM_EXT_UFS_FEATURE_SUP + 4)
> > -        goto wb_disabled;
> > -
> >       ext_ufs_feature = get_unaligned_be32(desc_buf +
> >                       DEVICE_DESC_PARAM_EXT_UFS_FEATURE_SUP);
>
> Does this code really have to be removed? I see a check of the
> UFS_DEVICE_QUIRK_SUPPORT_EXTENDED_FEATURES flag above the removed
> code but no check of the descriptor size?
it is not necessary to check this, but if you have concern, we could 
change to like this:


        if (desc_buf[DEVICE_DESC_PARAM_LEN] <
            DEVICE_DESC_PARAM_EXT_UFS_FEATURE_SUP + 4)
                goto wb_disabled;

then   hba->desc_size could be removed.

Kind regards,

Bean