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authorMartin Kepplinger <martin.kepplinger@puri.sm>2021-07-04 09:54:02 +0200
committerMartin K. Petersen <martin.petersen@oracle.com>2021-07-21 23:48:34 -0400
commited4246d37f3b94e429d020cac692434a00bae4cc (patch)
tree931be0a89e21c6786ef64fcbbb8d9f614e6bb29a /drivers/scsi/sd.c
parentf591a2e0548da88130c7b1c79f1f735273adc683 (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.c22
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).