Currently there are 4 driver flags to control system suspend/resume
behavior: DPM_FLAG_NO_DIRECT_COMPLETE, DPM_FLAG_SMART_PREPARE,
DPM_FLAG_SMART_SUSPEND and DPM_FLAG_MAY_SKIP_RESUME. Make these flags
visible in sysfs as read-only to get a brief understanding of the
expected behavior of each device during suspend/resume, so as to
facilitate suspend/resume debugging/tuning.
For example:
/sys/devices/pci0000:00/0000:00:15.1/power/driver_flags:4
(DPM_FLAG_SMART_SUSPEND)
/sys/devices/pci0000:00/0000:00:07.3/power/driver_flags:5
(DPM_FLAG_NO_DIRECT_COMPLETE | DPM_FLAG_SMART_SUSPEND)
Acked-by: Len Brown <[email protected]>
Signed-off-by: Chen Yu <[email protected]>
---
drivers/base/power/sysfs.c | 29 ++++++++++++++++++++++++++++-
1 file changed, 28 insertions(+), 1 deletion(-)
diff --git a/drivers/base/power/sysfs.c b/drivers/base/power/sysfs.c
index a1474fb67db9..48313a1040a5 100644
--- a/drivers/base/power/sysfs.c
+++ b/drivers/base/power/sysfs.c
@@ -607,6 +607,13 @@ static ssize_t async_store(struct device *dev, struct device_attribute *attr,
static DEVICE_ATTR_RW(async);
+static ssize_t driver_flags_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ return sysfs_emit(buf, "%x\n", dev->power.driver_flags);
+}
+static DEVICE_ATTR_RO(driver_flags);
+
#endif /* CONFIG_PM_SLEEP */
#endif /* CONFIG_PM_ADVANCED_DEBUG */
@@ -691,6 +698,20 @@ static const struct attribute_group pm_qos_flags_attr_group = {
.attrs = pm_qos_flags_attrs,
};
+static struct attribute *pm_driver_flags_attrs[] = {
+#ifdef CONFIG_PM_ADVANCED_DEBUG
+#ifdef CONFIG_PM_SLEEP
+ &dev_attr_driver_flags.attr,
+#endif
+#endif
+ NULL,
+};
+
+static const struct attribute_group pm_driver_flags_attr_group = {
+ .name = power_group_name,
+ .attrs = pm_driver_flags_attrs,
+};
+
int dpm_sysfs_add(struct device *dev)
{
int rc;
@@ -719,11 +740,17 @@ int dpm_sysfs_add(struct device *dev)
if (rc)
goto err_wakeup;
}
- rc = pm_wakeup_source_sysfs_add(dev);
+ rc = sysfs_merge_group(&dev->kobj, &pm_driver_flags_attr_group);
if (rc)
goto err_latency;
+
+ rc = pm_wakeup_source_sysfs_add(dev);
+ if (rc)
+ goto err_flags;
return 0;
+ err_flags:
+ sysfs_unmerge_group(&dev->kobj, &pm_driver_flags_attr_group);
err_latency:
sysfs_unmerge_group(&dev->kobj, &pm_qos_latency_tolerance_attr_group);
err_wakeup:
--
2.17.1
On Thu, Oct 22, 2020 at 11:23:24AM +0800, Chen Yu wrote:
> Currently there are 4 driver flags to control system suspend/resume
> behavior: DPM_FLAG_NO_DIRECT_COMPLETE, DPM_FLAG_SMART_PREPARE,
> DPM_FLAG_SMART_SUSPEND and DPM_FLAG_MAY_SKIP_RESUME. Make these flags
> visible in sysfs as read-only to get a brief understanding of the
> expected behavior of each device during suspend/resume, so as to
> facilitate suspend/resume debugging/tuning.
>
> For example:
> /sys/devices/pci0000:00/0000:00:15.1/power/driver_flags:4
> (DPM_FLAG_SMART_SUSPEND)
>
> /sys/devices/pci0000:00/0000:00:07.3/power/driver_flags:5
> (DPM_FLAG_NO_DIRECT_COMPLETE | DPM_FLAG_SMART_SUSPEND)
>
> Acked-by: Len Brown <[email protected]>
> Signed-off-by: Chen Yu <[email protected]>
> ---
> drivers/base/power/sysfs.c | 29 ++++++++++++++++++++++++++++-
> 1 file changed, 28 insertions(+), 1 deletion(-)
There is no Documentataion/ABI/ entry for your new file, which makes
this patch impossible to properly review by anyone, and prevents it from
being able to be accepted.
Please fix.
thanks,
greg k-h
Hi Greg,
thanks for taking a look at this.
On Thu, Oct 22, 2020 at 07:31:43AM +0200, Greg Kroah-Hartman wrote:
> On Thu, Oct 22, 2020 at 11:23:24AM +0800, Chen Yu wrote:
> > Currently there are 4 driver flags to control system suspend/resume
> > behavior: DPM_FLAG_NO_DIRECT_COMPLETE, DPM_FLAG_SMART_PREPARE,
> > DPM_FLAG_SMART_SUSPEND and DPM_FLAG_MAY_SKIP_RESUME. Make these flags
> > visible in sysfs as read-only to get a brief understanding of the
> > expected behavior of each device during suspend/resume, so as to
> > facilitate suspend/resume debugging/tuning.
> >
> > For example:
> > /sys/devices/pci0000:00/0000:00:15.1/power/driver_flags:4
> > (DPM_FLAG_SMART_SUSPEND)
> >
> > /sys/devices/pci0000:00/0000:00:07.3/power/driver_flags:5
> > (DPM_FLAG_NO_DIRECT_COMPLETE | DPM_FLAG_SMART_SUSPEND)
> >
> > Acked-by: Len Brown <[email protected]>
> > Signed-off-by: Chen Yu <[email protected]>
> > ---
> > drivers/base/power/sysfs.c | 29 ++++++++++++++++++++++++++++-
> > 1 file changed, 28 insertions(+), 1 deletion(-)
>
> There is no Documentataion/ABI/ entry for your new file, which makes
> this patch impossible to properly review by anyone, and prevents it from
> being able to be accepted.
>
> Please fix.
>
Okay, will add the entry in the document.
thanks,
Chenyu
> thanks,
>
> greg k-h