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| author |   Adamski, Krzysztof (Nokia - PL/Wroclaw) <krzysztof.adamski@nokia.com> | 2019-05-29 14:33:52 +0000 |
|---|---|---|
| committer |   Guenter Roeck <linux@roeck-us.net> | 2019-06-05 18:36:27 -0700 |
| commit | 38463721ec3c39acdabed3a89016ce6bb32a7543 (patch) | |
| tree | 4154a311c4aee5f43ada5b80fc0e148bec4c5b58 /drivers/hwmon/pmbus | |
| parent | hwmon: (core) add thermal sensors only if dev->of_node is present (diff) | |
| download | linux-dev-38463721ec3c39acdabed3a89016ce6bb32a7543.tar.xz linux-dev-38463721ec3c39acdabed3a89016ce6bb32a7543.zip | |
hwmon: (pmbus/core) mutex_lock write in pmbus_set_samples
update_lock is a mutex intended to protect write operations. It was not
taken, however, when _pmbus_write_word_data is called from
pmbus_set_samples() function which may cause problems especially when
some PMBUS_VIRT_* operation is implemented as a read-modify-write cycle.
This patch makes sure the lock is held during the operation.
Fixes: 49c4455dccf2 ("hwmon: (pmbus) Introduce PMBUS_VIRT_*_SAMPLES registers")
Signed-off-by: Krzysztof Adamski <krzysztof.adamski@nokia.com>
Reviewed-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
[groeck: Declared and initialized missing 'data' variable]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Diffstat (limited to 'drivers/hwmon/pmbus')
| -rw-r--r-- | drivers/hwmon/pmbus/pmbus_core.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c index ef7ee90ee785..48c2d5ae42a6 100644 --- a/drivers/hwmon/pmbus/pmbus_core.c +++ b/drivers/hwmon/pmbus/pmbus_core.c @@ -1942,11 +1942,14 @@ static ssize_t pmbus_set_samples(struct device *dev, long val; struct i2c_client *client = to_i2c_client(dev->parent); struct pmbus_samples_reg *reg = to_samples_reg(devattr); + struct pmbus_data *data = i2c_get_clientdata(client); if (kstrtol(buf, 0, &val) < 0) return -EINVAL; + mutex_lock(&data->update_lock); ret = _pmbus_write_word_data(client, reg->page, reg->attr->reg, val); + mutex_unlock(&data->update_lock); return ret ? : count; } |