patch "hid-sensor: Fix suspend/resume delay" added to staging-linus

PATCH [email protected] 2 participants 2 messages Jul 13, 2015 – Jul 14, 2015

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Stable branch HID IIO HID sensor hub drivers

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[email protected]

author maintainer Applied

2015-07-13 21:18 UTC #0 lore raw

This is a note to let you know that I've just added the patch titled

hid-sensor: Fix suspend/resume delay

to my staging git tree which can be found at
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging.git
in the staging-linus branch.

The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.)

The patch will hopefully also be merged in Linus's tree for the next -rc kernel release.

If you have any questions about this process, please let me know.

Quoted 1 line

From 1e25aa9641e8f3fa39cd5e46b4afcafd7f12a44b Mon Sep 17 00:00:00 2001

From: Srinivas Pandruvada <[email protected]>
Date: Mon, 1 Jun 2015 16:36:27 -0700
Subject: hid-sensor: Fix suspend/resume delay

By default all the sensors are runtime suspended state (lowest power state). During Linux suspend process, all the run time suspended devices are resumed and then suspended. This caused all sensors to power up and introduced delay in suspend time, when we introduced runtime PM for HID sensors. The opposite process happens during resume process.

To fix this, we do powerup process of the sensors only when the request is issued from user (raw or tiggerred). In this way when runtime, resume calls for powerup it will simply return as this will not match user requested state.

Note this is a regression fix as the increase in suspend / resume times can be substantial (report of 8 seconds on Len's laptop!)

Signed-off-by Srinivas Pandruvada <[email protected]>

Tested-by Len Brown <[email protected]>

Cc <[email protected]>

Signed-off-by Jonathan Cameron <[email protected]>

---
 drivers/iio/common/hid-sensors/hid-sensor-trigger.c | 11 ++++++++++-
 include/linux/hid-sensor-hub.h                      |  1 +
 2 files changed, 11 insertions(+), 1 deletion(-)

drivers/iio/common/hid-sensors/hid-sensor-trigger.c +10 -1

index 610fc98f88ef..595511022795 100644
@@ -36,6 +36,8 @@ static int _hid_sensor_power_state(struct hid_sensor_common *st, bool state)
 	s32 poll_value = 0;
 
 	if (state) {
+		if (!atomic_read(&st->user_requested_state))
+			return 0;
 		if (sensor_hub_device_open(st->hsdev))
 			return -EIO;

@@ -52,8 +54,12 @@ static int _hid_sensor_power_state(struct hid_sensor_common *st, bool state)
 
 		poll_value = hid_sensor_read_poll_value(st);
 	} else {
-		if (!atomic_dec_and_test(&st->data_ready))
+		int val;
+
+		val = atomic_dec_if_positive(&st->data_ready);
+		if (val < 0)
 			return 0;
+
 		sensor_hub_device_close(st->hsdev);
 		state_val = hid_sensor_get_usage_index(st->hsdev,
 			st->power_state.report_id,

@@ -92,9 +98,11 @@ EXPORT_SYMBOL(hid_sensor_power_state);
 
 int hid_sensor_power_state(struct hid_sensor_common *st, bool state)
 {
+
 #ifdef CONFIG_PM
 	int ret;
 
+	atomic_set(&st->user_requested_state, state);
 	if (state)
 		ret = pm_runtime_get_sync(&st->pdev->dev);
 	else {

@@ -109,6 +117,7 @@ int hid_sensor_power_state(struct hid_sensor_common *st, bool state)
 
  	return 0;
 #else
+	atomic_set(&st->user_requested_state, state);
 	return _hid_sensor_power_state(st, state);
 #endif
 }

include/linux/hid-sensor-hub.h +1 -0

index 0408421d885f..cd224dfd94d8 100644
@@ -230,6 +230,7 @@ struct hid_sensor_common {
 	struct platform_device *pdev;
 	unsigned usage_id;
 	atomic_t data_ready;
+	atomic_t user_requested_state;
 	struct iio_trigger *trigger;
 	struct hid_sensor_hub_attribute_info poll;
 	struct hid_sensor_hub_attribute_info report_state;

Signature · 1 line

2.4.5

Brown, Len

2015-07-14 02:18 UTC #1 lore raw

This patch fixes a regression starting in Linux-4.0, and thus should also be targeted to -stable.

I do not recommend that distros ship Linux Linux-4.0 or Linux-4.1 to users until this regression is fixed -- as some users will much prefer the kernel without the regression.

thanks,
-Len

Quoted 122 lines

-----Original Message-----
From: [email protected] [mailto:[email protected]]
Sent: Monday, July 13, 2015 5:19 PM
To: [email protected]; [email protected]; [email protected]; Brown, Len
Subject: patch "hid-sensor: Fix suspend/resume delay" added to staging- linus
This is a note to let you know that I've just added the patch titled
hid-sensor: Fix suspend/resume delay
to my staging git tree which can be found at
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging.git
in the staging-linus branch.
The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.)
The patch will hopefully also be merged in Linus's tree for the next -rc kernel release.
If you have any questions about this process, please let me know.
From 1e25aa9641e8f3fa39cd5e46b4afcafd7f12a44b Mon Sep 17 00:00:00 2001
From: Srinivas Pandruvada <[email protected]>
Date: Mon, 1 Jun 2015 16:36:27 -0700
Subject: hid-sensor: Fix suspend/resume delay
By default all the sensors are runtime suspended state (lowest power state). During Linux suspend process, all the run time suspended devices are resumed and then suspended. This caused all sensors to power up and introduced delay in suspend time, when we introduced runtime PM for HID sensors. The opposite process happens during resume process.
To fix this, we do powerup process of the sensors only when the request is issued from user (raw or tiggerred). In this way when runtime, resume calls for powerup it will simply return as this will not match user requested state.
Note this is a regression fix as the increase in suspend / resume times can be substantial (report of 8 seconds on Len's laptop!)
Signed-off-by Srinivas Pandruvada <[email protected]>
Tested-by Len Brown <[email protected]>
Cc <[email protected]>
Signed-off-by Jonathan Cameron <[email protected]>
---
 drivers/iio/common/hid-sensors/hid-sensor-trigger.c | 11 ++++++++++-
 include/linux/hid-sensor-hub.h                      |  1 +
 2 files changed, 11 insertions(+), 1 deletion(-)
drivers/iio/common/hid-sensors/hid-sensor-trigger.c +7 -1
index 610fc98f88ef..595511022795 100644
@@ -36,6 +36,8 @@ static int _hid_sensor_power_state(struct
 hid_sensor_common *st, bool state)
 	s32 poll_value = 0;
 
 	if (state) {
+		if (!atomic_read(&st->user_requested_state))
+			return 0;
 		if (sensor_hub_device_open(st->hsdev))
 			return -EIO;
@@ -52,8 +54,12 @@ static int _hid_sensor_power_state(struct
 hid_sensor_common *st, bool state)
 
 		poll_value = hid_sensor_read_poll_value(st);
 	} else {
-		if (!atomic_dec_and_test(&st->data_ready))
+		int val;
+
+		val = atomic_dec_if_positive(&st->data_ready);
+		if (val < 0)
 			return 0;
+
 		sensor_hub_device_close(st->hsdev);
 		state_val = hid_sensor_get_usage_index(st->hsdev,
drivers/iio/common/hid-sensors/hid-sensor-trigger.c +3 -0
 			st->power_state.report_id,
@@ -92,9 +98,11 @@ EXPORT_SYMBOL(hid_sensor_power_state);
 
 int hid_sensor_power_state(struct hid_sensor_common *st, bool state)
 {
+
 #ifdef CONFIG_PM
 	int ret;
 
+	atomic_set(&st->user_requested_state, state);
 	if (state)
 		ret = pm_runtime_get_sync(&st->pdev->dev);
 	else {
@@ -109,6 +117,7 @@ int hid_sensor_power_state(struct hid_sensor_common
 *st, bool state)
 
  	return 0;
 #else
+	atomic_set(&st->user_requested_state, state);
 	return _hid_sensor_power_state(st, state);
 #endif
}
include/linux/hid-sensor- renamed from include/linux/hid-sensor-hub.h +0 -0
hub.h
index 0408421d885f..cd224dfd94d8 100644
include/linux/hid-sensor-hub.h +1 -1
@@ -230,6 +230,7 @@ struct hid_sensor_common {
 	struct platform_device *pdev;
 	unsigned usage_id;
 	atomic_t data_ready;
+	atomic_t user_requested_state;
 	struct iio_trigger *trigger;
 	struct hid_sensor_hub_attribute_info poll;
 	struct hid_sensor_hub_attribute_info report_state;
--
2.4.5