4.19-stable review patch. If anyone has any objections, please let me know.
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From: Vamshi Gajjela vamshigajjela@google.com
commit ab9fd06cb8f0db0854291833fc40c789e43a361f upstream.
The ufshcd_add_delay_before_dme_cmd() always introduces a delay of MIN_DELAY_BEFORE_DME_CMDS_US between DME commands even when it's not required. The delay is added when the UFS host controller supplies the quirk UFSHCD_QUIRK_DELAY_BEFORE_DME_CMDS.
Fix the logic to update hba->last_dme_cmd_tstamp to ensure subsequent DME commands have the correct delay in the range of 0 to MIN_DELAY_BEFORE_DME_CMDS_US.
Update the timestamp at the end of the function to ensure it captures the latest time after any necessary delay has been applied.
Signed-off-by: Vamshi Gajjela vamshigajjela@google.com Link: https://lore.kernel.org/r/20240724135126.1786126-1-vamshigajjela@google.com Fixes: cad2e03d8607 ("ufs: add support to allow non standard behaviours (quirks)") Cc: stable@vger.kernel.org Reviewed-by: Bart Van Assche bvanassche@acm.org Signed-off-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/scsi/ufs/ufshcd.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-)
--- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -3592,11 +3592,16 @@ static inline void ufshcd_add_delay_befo min_sleep_time_us = MIN_DELAY_BEFORE_DME_CMDS_US - delta; else - return; /* no more delay required */ + min_sleep_time_us = 0; /* no more delay required */ }
- /* allow sleep for extra 50us if needed */ - usleep_range(min_sleep_time_us, min_sleep_time_us + 50); + if (min_sleep_time_us > 0) { + /* allow sleep for extra 50us if needed */ + usleep_range(min_sleep_time_us, min_sleep_time_us + 50); + } + + /* update the last_dme_cmd_tstamp */ + hba->last_dme_cmd_tstamp = ktime_get(); }
/**