[PATCH 7/8] i2c: stm32f7: fix reference leak when pm_runtime_get_sync fails

From: Qinglang Miao
Date: Tue Dec 01 2020 - 04:25:02 EST


The PM reference count is not expected to be incremented on
return in these stm32f7_i2c_xx serious functions.

However, pm_runtime_get_sync will increment the PM reference
count even failed. Forgetting to putting operation will result
in a reference leak here.

Replace it with pm_runtime_resume_and_get to keep usage
counter balanced.

Fixes: ea6dd25deeb5 ("i2c: stm32f7: add PM_SLEEP suspend/resume support")
Reported-by: Hulk Robot <hulkci@xxxxxxxxxx>
Signed-off-by: Qinglang Miao <miaoqinglang@xxxxxxxxxx>
---
drivers/i2c/busses/i2c-stm32f7.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/i2c/busses/i2c-stm32f7.c b/drivers/i2c/busses/i2c-stm32f7.c
index f41f51a17..72fd5bdd6 100644
--- a/drivers/i2c/busses/i2c-stm32f7.c
+++ b/drivers/i2c/busses/i2c-stm32f7.c
@@ -1643,7 +1643,7 @@ static int stm32f7_i2c_xfer(struct i2c_adapter *i2c_adap,
i2c_dev->msg_id = 0;
f7_msg->smbus = false;

- ret = pm_runtime_get_sync(i2c_dev->dev);
+ ret = pm_runtime_resume_and_get(i2c_dev->dev);
if (ret < 0)
return ret;

@@ -1689,7 +1689,7 @@ static int stm32f7_i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr,
f7_msg->read_write = read_write;
f7_msg->smbus = true;

- ret = pm_runtime_get_sync(dev);
+ ret = pm_runtime_resume_and_get(dev);
if (ret < 0)
return ret;

@@ -1790,7 +1790,7 @@ static int stm32f7_i2c_reg_slave(struct i2c_client *slave)
if (ret)
return ret;

- ret = pm_runtime_get_sync(dev);
+ ret = pm_runtime_resume_and_get(dev);
if (ret < 0)
return ret;

@@ -1871,7 +1871,7 @@ static int stm32f7_i2c_unreg_slave(struct i2c_client *slave)

WARN_ON(!i2c_dev->slave[id]);

- ret = pm_runtime_get_sync(i2c_dev->dev);
+ ret = pm_runtime_resume_and_get(i2c_dev->dev);
if (ret < 0)
return ret;

@@ -2268,7 +2268,7 @@ static int stm32f7_i2c_regs_backup(struct stm32f7_i2c_dev *i2c_dev)
int ret;
struct stm32f7_i2c_regs *backup_regs = &i2c_dev->backup_regs;

- ret = pm_runtime_get_sync(i2c_dev->dev);
+ ret = pm_runtime_resume_and_get(i2c_dev->dev);
if (ret < 0)
return ret;

@@ -2290,7 +2290,7 @@ static int stm32f7_i2c_regs_restore(struct stm32f7_i2c_dev *i2c_dev)
int ret;
struct stm32f7_i2c_regs *backup_regs = &i2c_dev->backup_regs;

- ret = pm_runtime_get_sync(i2c_dev->dev);
+ ret = pm_runtime_resume_and_get(i2c_dev->dev);
if (ret < 0)
return ret;

--
2.23.0