2018-02-24 22:44:02

by Tobias Jordan

Subject: [PATCH] i2c: cadence: Fix PM device usage count

pm_runtime_get_sync() increases the device's usage count even when
reporting an error, so add a call to pm_runtime_put_noidle() in the
error branch.

Fixes: 7fa32329ca03 ("i2c: cadence: Move to sensible power management")
Signed-off-by: Tobias Jordan <[email protected]>
---
This is one of a number of patches for problems found using coccinelle
scripting in the SIL2LinuxMP project. The patch has been compile-tested;
it's based on linux-next-20180223.

For a discussion of the corresponding issue, see
https://marc.info/?l=linux-pm&m=151904483924999&w=2

drivers/i2c/busses/i2c-cadence.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/i2c/busses/i2c-cadence.c b/drivers/i2c/busses/i2c-cadence.c
index b13605718291..898faa7fbac5 100644
--- a/drivers/i2c/busses/i2c-cadence.c
+++ b/drivers/i2c/busses/i2c-cadence.c
@@ -574,8 +574,10 @@ static int cdns_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
bool hold_quirk;

ret = pm_runtime_get_sync(id->dev);
- if (ret < 0)
+ if (ret < 0) {
+ pm_runtime_put_noidle(id->dev);
return ret;
+ }
/* Check if the bus is free */
if (cdns_i2c_readreg(CDNS_I2C_SR_OFFSET) & CDNS_I2C_SR_BA) {
ret = -EAGAIN;
--
2.11.0

2018-02-26 09:21:51

by Nicholas Mc Guire

Subject: Re: [SIL2review] [PATCH] i2c: cadence: Fix PM device usage count

On Sat, Feb 24, 2018 at 11:42:38PM +0100, Tobias Jordan wrote:
> pm_runtime_get_sync() increases the device's usage count even when
> reporting an error, so add a call to pm_runtime_put_noidle() in the
> error branch.
>
> Fixes: 7fa32329ca03 ("i2c: cadence: Move to sensible power management")
> Signed-off-by: Tobias Jordan <[email protected]>
> ---
> This is one of a number of patches for problems found using coccinelle
> scripting in the SIL2LinuxMP project. The patch has been compile-tested;
> it's based on linux-next-20180223.
>
> For a discussion of the corresponding issue, see
> https://marc.info/?l=linux-pm&m=151904483924999&w=2

just wondering if that should not be above the --- as:

Link: https://marc.info/?l=linux-pm&m=151904483924999&w=2

notably as the discussion about why not to fix it in __pm_runtime_resume
would seem reasonable to carry into the mainline logs.

thx!
hforat

>
> drivers/i2c/busses/i2c-cadence.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/i2c/busses/i2c-cadence.c b/drivers/i2c/busses/i2c-cadence.c
> index b13605718291..898faa7fbac5 100644
> --- a/drivers/i2c/busses/i2c-cadence.c
> +++ b/drivers/i2c/busses/i2c-cadence.c
> @@ -574,8 +574,10 @@ static int cdns_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
> bool hold_quirk;
>
> ret = pm_runtime_get_sync(id->dev);
> - if (ret < 0)
> + if (ret < 0) {
> + pm_runtime_put_noidle(id->dev);
> return ret;
> + }
> /* Check if the bus is free */
> if (cdns_i2c_readreg(CDNS_I2C_SR_OFFSET) & CDNS_I2C_SR_BA) {
> ret = -EAGAIN;
> --
> 2.11.0
>
> _______________________________________________
> SIL2review mailing list
> [email protected]
> https://lists.osadl.org/mailman/listinfo/sil2review