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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 10/10/24 12:52 AM, SEO HOYOUNG wrote: > Performance problems may occur if there is a problem with the > asymmetric connected lane such as h/w failure. > Currently, only check connected lane for rx/tx is checked if it is not 0. > But it should also be checked if it is asymmetrically connected. > > Signed-off-by: SEO HOYOUNG > --- > drivers/ufs/core/ufshcd.c | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c > index 24a32e2fd75e..387eec6f19ef 100644 > --- a/drivers/ufs/core/ufshcd.c > +++ b/drivers/ufs/core/ufshcd.c > @@ -4540,6 +4540,14 @@ static int ufshcd_get_max_pwr_mode(struct ufs_hba *hba) > return -EINVAL; > } > > + if (pwr_info->lane_rx != pwr_info->lane_tx) { > + dev_err(hba->dev, "%s: asymmetric connected lanes. rx=%d, tx=%d\n", > + __func__, > + pwr_info->lane_rx, > + pwr_info->lane_tx); > + return -EINVAL; > + } > + > /* > * First, get the maximum gears of HS speed. > * If a zero value, it means there is no HSGEAR capability. It seems to me that symmetry of the number of lanes is required by the UFS standard? From the UFS standard: "An equal number of downstream and upstream lanes shall be provided in each link." Hence: Reviewed-by: Bart Van Assche