diff options
| author | Martin Kepplinger <martin.kepplinger@puri.sm> | 2021-07-04 09:54:02 +0200 |
|---|---|---|
| committer | Martin K. Petersen <martin.petersen@oracle.com> | 2021-07-21 23:48:34 -0400 |
| commit | ed4246d37f3b94e429d020cac692434a00bae4cc (patch) | |
| tree | 931be0a89e21c6786ef64fcbbb8d9f614e6bb29a /drivers/scsi/sd.c | |
| parent | f591a2e0548da88130c7b1c79f1f735273adc683 (diff) | |
scsi: sd: REQUEST SENSE for BLIST_IGN_MEDIA_CHANGE devices in runtime_resume()
For SD card reader devices that have the BLIST_IGN_MEDIA_CHANGE flag
set, a MEDIUM MAY HAVE CHANGED unit attention is established after
resuming from runtime suspend. Send a REQUEST SENSE to consume the UA.
The "downside" is that for these devices we now rely on users to not
change the medium (SD card) *during* a runtime suspend/resume cycle,
i.e. when not unmounting.
To enable runtime PM for an SD cardreader (device number 0:0:0:0), do:
echo 0 > /sys/module/block/parameters/events_dfl_poll_msecs
echo 1000 > /sys/bus/scsi/devices/0:0:0:0/power/autosuspend_delay_ms
echo auto > /sys/bus/scsi/devices/0:0:0:0/power/control
[mkp: use scsi_device flag instead of poking at BLIST]
Link: https://lore.kernel.org/r/20210704075403.147114-3-martin.kepplinger@puri.sm
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin Kepplinger <martin.kepplinger@puri.sm>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Diffstat (limited to 'drivers/scsi/sd.c')
| -rw-r--r-- | drivers/scsi/sd.c | 22 |
1 files changed, 21 insertions, 1 deletions
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index b8d55af763f9..e7ef4728d5eb 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -110,6 +110,7 @@ static void sd_shutdown(struct device *); static int sd_suspend_system(struct device *); static int sd_suspend_runtime(struct device *); static int sd_resume(struct device *); +static int sd_resume_runtime(struct device *); static void sd_rescan(struct device *); static blk_status_t sd_init_command(struct scsi_cmnd *SCpnt); static void sd_uninit_command(struct scsi_cmnd *SCpnt); @@ -604,7 +605,7 @@ static const struct dev_pm_ops sd_pm_ops = { .poweroff = sd_suspend_system, .restore = sd_resume, .runtime_suspend = sd_suspend_runtime, - .runtime_resume = sd_resume, + .runtime_resume = sd_resume_runtime, }; static struct scsi_driver sd_template = { @@ -3716,6 +3717,25 @@ static int sd_resume(struct device *dev) return ret; } +static int sd_resume_runtime(struct device *dev) +{ + struct scsi_disk *sdkp = dev_get_drvdata(dev); + struct scsi_device *sdp = sdkp->device; + + if (sdp->ignore_media_change) { + /* clear the device's sense data */ + static const u8 cmd[10] = { REQUEST_SENSE }; + + if (scsi_execute(sdp, cmd, DMA_NONE, NULL, 0, NULL, + NULL, sdp->request_queue->rq_timeout, 1, 0, + RQF_PM, NULL)) + sd_printk(KERN_NOTICE, sdkp, + "Failed to clear sense data\n"); + } + + return sd_resume(dev); +} + /** * init_sd - entry point for this driver (both when built in or when * a module). |