2022-08-10 05:37:05

by Zev Weiss

[permalink] [raw]
Subject: [PATCH] hwmon: (nct6775) Fix platform driver suspend regression

Commit c3963bc0a0cf ("hwmon: (nct6775) Split core and platform
driver") introduced a slight change in nct6775_suspend() in order to
avoid an otherwise-needless symbol export for nct6775_update_device(),
replacing a call to that function with a simple dev_get_drvdata()
instead.

Though the exact details of how this happens aren't yet fully known,
it turns out that this breaks suspend/resume in at least some
circumstances. To fix this (possibly only temporarily until the
problem is better understood), just add the symbol export and return
to using nct6775_update_device() as was employed previously.

Reported-by: Zoltán Kővágó <[email protected]>
Tested-by: Zoltán Kővágó <[email protected]>
Fixes: c3963bc0a0cf ("hwmon: (nct6775) Split core and platform driver")
Cc: [email protected]
Signed-off-by: Zev Weiss <[email protected]>
---
drivers/hwmon/nct6775-core.c | 3 ++-
drivers/hwmon/nct6775-platform.c | 2 +-
drivers/hwmon/nct6775.h | 2 ++
3 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/hwmon/nct6775-core.c b/drivers/hwmon/nct6775-core.c
index 446964cbae4c..da9ec6983e13 100644
--- a/drivers/hwmon/nct6775-core.c
+++ b/drivers/hwmon/nct6775-core.c
@@ -1480,7 +1480,7 @@ static int nct6775_update_pwm_limits(struct device *dev)
return 0;
}

-static struct nct6775_data *nct6775_update_device(struct device *dev)
+struct nct6775_data *nct6775_update_device(struct device *dev)
{
struct nct6775_data *data = dev_get_drvdata(dev);
int i, j, err = 0;
@@ -1615,6 +1615,7 @@ static struct nct6775_data *nct6775_update_device(struct device *dev)
mutex_unlock(&data->update_lock);
return err ? ERR_PTR(err) : data;
}
+EXPORT_SYMBOL_GPL(nct6775_update_device);

/*
* Sysfs callback functions
diff --git a/drivers/hwmon/nct6775-platform.c b/drivers/hwmon/nct6775-platform.c
index ab30437221ce..41c97cfacfb8 100644
--- a/drivers/hwmon/nct6775-platform.c
+++ b/drivers/hwmon/nct6775-platform.c
@@ -359,7 +359,7 @@ static int __maybe_unused nct6775_suspend(struct device *dev)
{
int err;
u16 tmp;
- struct nct6775_data *data = dev_get_drvdata(dev);
+ struct nct6775_data *data = nct6775_update_device(dev);

if (IS_ERR(data))
return PTR_ERR(data);
diff --git a/drivers/hwmon/nct6775.h b/drivers/hwmon/nct6775.h
index 93f708148e65..be41848c3cd2 100644
--- a/drivers/hwmon/nct6775.h
+++ b/drivers/hwmon/nct6775.h
@@ -196,6 +196,8 @@ static inline int nct6775_write_value(struct nct6775_data *data, u16 reg, u16 va
return regmap_write(data->regmap, reg, value);
}

+struct nct6775_data *nct6775_update_device(struct device *dev);
+
bool nct6775_reg_is_word_sized(struct nct6775_data *data, u16 reg);
int nct6775_probe(struct device *dev, struct nct6775_data *data,
const struct regmap_config *regmapcfg);
--
2.37.1