diff options
| author | subhashj@codeaurora.org <subhashj@codeaurora.org> | 2016-11-23 16:33:08 -0800 |
|---|---|---|
| committer | Martin K. Petersen <martin.petersen@oracle.com> | 2016-11-29 12:06:57 -0500 |
| commit | 0b257734344aa89b565bd148ff94f29aa873ffa6 (patch) | |
| tree | 25ae4aacf23e0c3cb81cb3cfdcf9830b99516f6d /drivers/scsi/ufs | |
| parent | f37e9f8cf8bc681250880f8c1372fb882c9379b8 (diff) | |
scsi: ufs: optimize system suspend handling
Consider following sequence of events:
1. UFS is runtime suspended, link_state = Hibern8, device_state = sleep
2. System goes into system suspend, ufshcd_system_suspend() brings both
link and device to active state and then puts the device in Power_Down
state and link in OFF state.
3. System resumes at some later point in time, ufshcd_system_resume()
doesn't do anything as UFS state is runtime suspended. Note that link
is still on OFF state and device is in Power_Down state.
4. Now system again goes into suspend without any UFS accesses before it.
ufshcd_system_suspend() again brings both link and device to active
state and then puts the device in Power_Down state and link if OFF
state. But it's unnecessary to bring the link & device in active state
as both link and device are already in desired low power states. This
change fixes this issue by adding proper state checks in
ufshcd_system_suspend().
Reviewed-by: Gilad Broner <gbroner@codeaurora.org>
Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Diffstat (limited to 'drivers/scsi/ufs')
| -rw-r--r-- | drivers/scsi/ufs/ufshcd.c | 15 |
1 files changed, 6 insertions, 9 deletions
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index b82607856607..4b6cc0773681 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -6272,16 +6272,13 @@ int ufshcd_system_suspend(struct ufs_hba *hba) if (!hba || !hba->is_powered) return 0; - if (pm_runtime_suspended(hba->dev)) { - if (hba->rpm_lvl == hba->spm_lvl) - /* - * There is possibility that device may still be in - * active state during the runtime suspend. - */ - if ((ufs_get_pm_lvl_to_dev_pwr_mode(hba->spm_lvl) == - hba->curr_dev_pwr_mode) && !hba->auto_bkops_enabled) - goto out; + if ((ufs_get_pm_lvl_to_dev_pwr_mode(hba->spm_lvl) == + hba->curr_dev_pwr_mode) && + (ufs_get_pm_lvl_to_link_pwr_state(hba->spm_lvl) == + hba->uic_link_state)) + goto out; + if (pm_runtime_suspended(hba->dev)) { /* * UFS device and/or UFS link low power states during runtime * suspend seems to be different than what is expected during |