[PATCH 2/3] scsi: add hooks for host runtime power management

Lin Ming
2011-11-02T06:21:39Z

Adds ->suspend and ->resume callbacks in struct scsi_host_template
to do host runtime power management.

Signed-off-by: Lin Ming <ming.m.lin@intel.com>
---
drivers/scsi/scsi_pm.c | 34 +++++++++++++++++++++++++++++++---
include/scsi/scsi_host.h | 8 ++++++++
2 files changed, 39 insertions(+), 3 deletions(-)

diff --git a/drivers/scsi/scsi_pm.c b/drivers/scsi/scsi_pm.c
index 1be6c5a..5742bed2 100644
--- a/drivers/scsi/scsi_pm.c
+++ b/drivers/scsi/scsi_pm.c
@@ -42,6 +42,28 @@ static int scsi_dev_type_resume(struct device *dev)
return err;
}

+static int scsi_host_suspend(struct device *dev)
+{
+ struct Scsi_Host *shost = dev_to_shost(dev);
+ int err = 0;
+
+ if (shost->hostt->suspend)
+ err = shost->hostt->suspend(shost);
+
+ return err;
+}
+
+static int scsi_host_resume(struct device *dev)
+{
+ struct Scsi_Host *shost = dev_to_shost(dev);
+ int err = 0;
+
+ if (shost->hostt->resume)
+ err = shost->hostt->resume(shost);
+
+ return err;
+}
+
#ifdef CONFIG_PM_SLEEP

static int scsi_bus_suspend_common(struct device *dev, pm_message_t msg)
@@ -106,7 +128,10 @@ static int scsi_runtime_suspend(struct device *dev)
round_jiffies_up_relative(HZ/10)));
}

- /* Insert hooks here for targets, hosts, and transport classes */
+ /* Insert hooks here for targets and transport classes */
+
+ if (scsi_is_host_device(dev))
+ err = scsi_host_suspend(dev);

return err;
}
@@ -119,7 +144,10 @@ static int scsi_runtime_resume(struct device *dev)
if (scsi_is_sdev_device(dev))
err = scsi_dev_type_resume(dev);

- /* Insert hooks here for targets, hosts, and transport classes */
+ /* Insert hooks here for targets and transport classes */
+
+ if (scsi_is_host_device(dev))
+ err = scsi_host_resume(dev);

return err;
}
@@ -132,7 +160,7 @@ static int scsi_runtime_idle(struct device *dev)

/* Insert hooks here for targets, hosts, and transport classes */

- if (scsi_is_sdev_device(dev))
+ if (scsi_is_sdev_device(dev) || scsi_is_host_device(dev))
err = pm_schedule_suspend(dev, 100);
else
err = pm_runtime_suspend(dev);
diff --git a/include/scsi/scsi_host.h b/include/scsi/scsi_host.h
index f1f2644..512e2a0 100644
--- a/include/scsi/scsi_host.h
+++ b/include/scsi/scsi_host.h
@@ -356,6 +356,14 @@ struct scsi_host_template {
enum blk_eh_timer_return (*eh_timed_out)(struct scsi_cmnd *);

/*
+ * Optional routine for scsi host runtime pm.
+ *
+ * Status: OPTIONAL
+ */
+ int (*suspend)(struct Scsi_Host *);
+ int (*resume)(struct Scsi_Host *);
+
+ /*
* Name of proc directory
*/
const char *proc_name;
--
1.7.2.5