The patches of this series were originally in the series "Add suspend to
ram support for PCIe on J7200" [1].
There is no changes compared to the patches in the series [1].
The goal is to wakeup the controller during the suspend stage to be able
to use it during suspend_noirq stage.
As autosuspend is enabled, the controller can be suspended at suspend_noirq
stage. But runtime pm is disabled in suspend_late stage. So it's not
possible to wakeup the controller during suspend_noirq.
The trick is to force the wakeup of the controller during suspend stage.
[1] https://lore.kernel.org/all/[email protected]/
Signed-off-by: Thomas Richard <[email protected]>
---
Thomas Richard (2):
i2c: omap: switch to NOIRQ_SYSTEM_SLEEP_PM_OPS() and RUNTIME_PM_OPS()
i2c: omap: wakeup the controller during suspend() callback
drivers/i2c/busses/i2c-omap.c | 36 +++++++++++++++++++++++++++++-------
1 file changed, 29 insertions(+), 7 deletions(-)
---
base-commit: 0719fea199617c798ad3a9158916066ac17219b2
change-id: 20240613-i2c-omap-wakeup-controller-during-suspend-895adf95a005
Best regards,
--
Thomas Richard <[email protected]>
Replace SET_NOIRQ_SYSTEM_SLEEP_PM_OPS() and SET_RUNTIME_PM_OPS() by
NOIRQ_SYSTEM_SLEEP_PM_OPS() and RUNTIME_PM_OPS().
The usage of pm_ptr() and these more recent macros allows the compiler to
see and drop the dead code.
The unnecessary '__maybe_unused' annotations on PM functions can be
removed.
Signed-off-by: Thomas Richard <[email protected]>
---
drivers/i2c/busses/i2c-omap.c | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)
diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 30a5ea282a8b..410c8b37f768 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -1534,7 +1534,7 @@ static void omap_i2c_remove(struct platform_device *pdev)
pm_runtime_disable(&pdev->dev);
}
-static int __maybe_unused omap_i2c_runtime_suspend(struct device *dev)
+static int omap_i2c_runtime_suspend(struct device *dev)
{
struct omap_i2c_dev *omap = dev_get_drvdata(dev);
@@ -1560,7 +1560,7 @@ static int __maybe_unused omap_i2c_runtime_suspend(struct device *dev)
return 0;
}
-static int __maybe_unused omap_i2c_runtime_resume(struct device *dev)
+static int omap_i2c_runtime_resume(struct device *dev)
{
struct omap_i2c_dev *omap = dev_get_drvdata(dev);
@@ -1575,10 +1575,10 @@ static int __maybe_unused omap_i2c_runtime_resume(struct device *dev)
}
static const struct dev_pm_ops omap_i2c_pm_ops = {
- SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
- pm_runtime_force_resume)
- SET_RUNTIME_PM_OPS(omap_i2c_runtime_suspend,
- omap_i2c_runtime_resume, NULL)
+ NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+ pm_runtime_force_resume)
+ RUNTIME_PM_OPS(omap_i2c_runtime_suspend,
+ omap_i2c_runtime_resume, NULL)
};
static struct platform_driver omap_i2c_driver = {
@@ -1586,7 +1586,7 @@ static struct platform_driver omap_i2c_driver = {
.remove_new = omap_i2c_remove,
.driver = {
.name = "omap_i2c",
- .pm = &omap_i2c_pm_ops,
+ .pm = pm_ptr(&omap_i2c_pm_ops),
.of_match_table = of_match_ptr(omap_i2c_of_match),
},
};
--
2.39.2
A device may need the controller up during suspend_noirq() or
resume_noirq().
But if the controller is autosuspended, there is no way to wakeup it during
suspend_noirq() or resume_noirq() because runtime pm is disabled at this
time.
The suspend() callback wakes up the controller, so it is available until
its suspend_noirq() callback (pm_runtime_force_suspend()).
During the resume, it's restored by resume_noirq() callback
(pm_runtime_force_resume()). Then resume() callback enables autosuspend.
So the controller is up during a little time slot in suspend and resume
sequences even if it's not used.
Reviewed-by: Andi Shyti <[email protected]>
Acked-by: Wolfram Sang <[email protected]>
Reviewed-by: Tony Lindgren <[email protected]>
Signed-off-by: Thomas Richard <[email protected]>
---
drivers/i2c/busses/i2c-omap.c | 22 ++++++++++++++++++++++
1 file changed, 22 insertions(+)
diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 410c8b37f768..35a3f0a64986 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -1574,9 +1574,31 @@ static int omap_i2c_runtime_resume(struct device *dev)
return 0;
}
+static int omap_i2c_suspend(struct device *dev)
+{
+ /*
+ * If the controller is autosuspended, there is no way to wakeup it once
+ * runtime pm is disabled (in suspend_late()).
+ * But a device may need the controller up during suspend_noirq() or
+ * resume_noirq().
+ * Wakeup the controller while runtime pm is enabled, so it is available
+ * until its suspend_noirq(), and from resume_noirq().
+ */
+ return pm_runtime_resume_and_get(dev);
+}
+
+static int omap_i2c_resume(struct device *dev)
+{
+ pm_runtime_mark_last_busy(dev);
+ pm_runtime_put_autosuspend(dev);
+
+ return 0;
+}
+
static const struct dev_pm_ops omap_i2c_pm_ops = {
NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
pm_runtime_force_resume)
+ SYSTEM_SLEEP_PM_OPS(omap_i2c_suspend, omap_i2c_resume)
RUNTIME_PM_OPS(omap_i2c_runtime_suspend,
omap_i2c_runtime_resume, NULL)
};
--
2.39.2
Hi
On Thu, 13 Jun 2024 15:13:26 +0200, Thomas Richard wrote:
> The patches of this series were originally in the series "Add suspend to
> ram support for PCIe on J7200" [1].
> There is no changes compared to the patches in the series [1].
>
> The goal is to wakeup the controller during the suspend stage to be able
> to use it during suspend_noirq stage.
> As autosuspend is enabled, the controller can be suspended at suspend_noirq
> stage. But runtime pm is disabled in suspend_late stage. So it's not
> possible to wakeup the controller during suspend_noirq.
> The trick is to force the wakeup of the controller during suspend stage.
>
> [...]
Applied to i2c/i2c-host on
git://git.kernel.org/pub/scm/linux/kernel/git/andi.shyti/linux.git
Thank you,
Andi
Patches applied
===============
[1/2] i2c: omap: switch to NOIRQ_SYSTEM_SLEEP_PM_OPS() and RUNTIME_PM_OPS()
commit: 659eb16247d04f442a014fe2dd8b7fa936dfccb5
[2/2] i2c: omap: wakeup the controller during suspend() callback
commit: 8a2ebb775a497a95a79a8ac83027a4f159c36f32