* [PATCH AUTOSEL 4.19 075/128] PM / devfreq: passive: Use non-devm notifiers
[not found] <20190922185418.2158-1-sashal@kernel.org>
@ 2019-09-22 18:53 ` Sasha Levin
2019-09-23 20:38 ` Leonard Crestez
2019-09-22 18:53 ` [PATCH AUTOSEL 4.19 076/128] PM / devfreq: exynos-bus: Correct clock enable sequence Sasha Levin
1 sibling, 1 reply; 4+ messages in thread
From: Sasha Levin @ 2019-09-22 18:53 UTC (permalink / raw)
To: linux-kernel, stable
Cc: Leonard Crestez, Chanwoo Choi, MyungJoo Ham, Sasha Levin,
linux-pm
From: Leonard Crestez <leonard.crestez@nxp.com>
[ Upstream commit 0ef7c7cce43f6ecc2b96d447e69b2900a9655f7c ]
The devfreq passive governor registers and unregisters devfreq
transition notifiers on DEVFREQ_GOV_START/GOV_STOP using devm wrappers.
If devfreq itself is registered with devm then a warning is triggered on
rmmod from devm_devfreq_unregister_notifier. Call stack looks like this:
devm_devfreq_unregister_notifier+0x30/0x40
devfreq_passive_event_handler+0x4c/0x88
devfreq_remove_device.part.8+0x6c/0x9c
devm_devfreq_dev_release+0x18/0x20
release_nodes+0x1b0/0x220
devres_release_all+0x78/0x84
device_release_driver_internal+0x100/0x1c0
driver_detach+0x4c/0x90
bus_remove_driver+0x7c/0xd0
driver_unregister+0x2c/0x58
platform_driver_unregister+0x10/0x18
imx_devfreq_platdrv_exit+0x14/0xd40 [imx_devfreq]
This happens because devres_release_all will first remove all the nodes
into a separate todo list so the nested devres_release from
devm_devfreq_unregister_notifier won't find anything.
Fix the warning by calling the non-devm APIS for frequency notification.
Using devm wrappers is not actually useful for a governor anyway: it
relies on the devfreq core to correctly match the GOV_START/GOV_STOP
notifications.
Fixes: 996133119f57 ("PM / devfreq: Add new passive governor")
Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
Acked-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/devfreq/governor_passive.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/devfreq/governor_passive.c b/drivers/devfreq/governor_passive.c
index 3bc29acbd54e8..22fd41b4c1098 100644
--- a/drivers/devfreq/governor_passive.c
+++ b/drivers/devfreq/governor_passive.c
@@ -168,12 +168,12 @@ static int devfreq_passive_event_handler(struct devfreq *devfreq,
p_data->this = devfreq;
nb->notifier_call = devfreq_passive_notifier_call;
- ret = devm_devfreq_register_notifier(dev, parent, nb,
+ ret = devfreq_register_notifier(parent, nb,
DEVFREQ_TRANSITION_NOTIFIER);
break;
case DEVFREQ_GOV_STOP:
- devm_devfreq_unregister_notifier(dev, parent, nb,
- DEVFREQ_TRANSITION_NOTIFIER);
+ WARN_ON(devfreq_unregister_notifier(parent, nb,
+ DEVFREQ_TRANSITION_NOTIFIER));
break;
default:
break;
--
2.20.1
^ permalink raw reply related [flat|nested] 4+ messages in thread* [PATCH AUTOSEL 4.19 076/128] PM / devfreq: exynos-bus: Correct clock enable sequence
[not found] <20190922185418.2158-1-sashal@kernel.org>
2019-09-22 18:53 ` [PATCH AUTOSEL 4.19 075/128] PM / devfreq: passive: Use non-devm notifiers Sasha Levin
@ 2019-09-22 18:53 ` Sasha Levin
1 sibling, 0 replies; 4+ messages in thread
From: Sasha Levin @ 2019-09-22 18:53 UTC (permalink / raw)
To: linux-kernel, stable
Cc: Kamil Konieczny, Chanwoo Choi, MyungJoo Ham, Sasha Levin,
linux-pm, linux-samsung-soc
From: Kamil Konieczny <k.konieczny@partner.samsung.com>
[ Upstream commit 2c2b20e0da89c76759ee28c6824413ab2fa3bfc6 ]
Regulators should be enabled before clocks to avoid h/w hang. This
require change in exynos_bus_probe() to move exynos_bus_parse_of()
after exynos_bus_parent_parse_of() and change in error handling.
Similar change is needed in exynos_bus_exit() where clock should be
disabled before regulators.
Signed-off-by: Kamil Konieczny <k.konieczny@partner.samsung.com>
Acked-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/devfreq/exynos-bus.c | 31 +++++++++++++++++--------------
1 file changed, 17 insertions(+), 14 deletions(-)
diff --git a/drivers/devfreq/exynos-bus.c b/drivers/devfreq/exynos-bus.c
index c25658b265988..24a9658348d78 100644
--- a/drivers/devfreq/exynos-bus.c
+++ b/drivers/devfreq/exynos-bus.c
@@ -194,11 +194,10 @@ static void exynos_bus_exit(struct device *dev)
if (ret < 0)
dev_warn(dev, "failed to disable the devfreq-event devices\n");
- if (bus->regulator)
- regulator_disable(bus->regulator);
-
dev_pm_opp_of_remove_table(dev);
clk_disable_unprepare(bus->clk);
+ if (bus->regulator)
+ regulator_disable(bus->regulator);
}
/*
@@ -386,6 +385,7 @@ static int exynos_bus_probe(struct platform_device *pdev)
struct exynos_bus *bus;
int ret, max_state;
unsigned long min_freq, max_freq;
+ bool passive = false;
if (!np) {
dev_err(dev, "failed to find devicetree node\n");
@@ -399,27 +399,27 @@ static int exynos_bus_probe(struct platform_device *pdev)
bus->dev = &pdev->dev;
platform_set_drvdata(pdev, bus);
- /* Parse the device-tree to get the resource information */
- ret = exynos_bus_parse_of(np, bus);
- if (ret < 0)
- return ret;
-
profile = devm_kzalloc(dev, sizeof(*profile), GFP_KERNEL);
- if (!profile) {
- ret = -ENOMEM;
- goto err;
- }
+ if (!profile)
+ return -ENOMEM;
node = of_parse_phandle(dev->of_node, "devfreq", 0);
if (node) {
of_node_put(node);
- goto passive;
+ passive = true;
} else {
ret = exynos_bus_parent_parse_of(np, bus);
+ if (ret < 0)
+ return ret;
}
+ /* Parse the device-tree to get the resource information */
+ ret = exynos_bus_parse_of(np, bus);
if (ret < 0)
- goto err;
+ goto err_reg;
+
+ if (passive)
+ goto passive;
/* Initialize the struct profile and governor data for parent device */
profile->polling_ms = 50;
@@ -510,6 +510,9 @@ static int exynos_bus_probe(struct platform_device *pdev)
err:
dev_pm_opp_of_remove_table(dev);
clk_disable_unprepare(bus->clk);
+err_reg:
+ if (!passive)
+ regulator_disable(bus->regulator);
return ret;
}
--
2.20.1
^ permalink raw reply related [flat|nested] 4+ messages in thread