RE: [EXT] [PATCH] i2c: busses: Fix a reference count leak.

[Andy Duan]

From: wu000273@xxxxxxx <wu000273@xxxxxxx> Sent: Sunday, June 14, 2020 6:12 AM
> From: Qiushi Wu <wu000273@xxxxxxx>
> 
> pm_runtime_get_sync() increments the runtime PM usage counter even
> when it returns an error code. Thus call pm_runtime_put_noidle() if
> pm_runtime_get_sync() fails.
> 
> Fixes: 13d6eb20fc79 ("i2c: imx-lpi2c: add runtime pm support")
> Signed-off-by: Qiushi Wu <wu000273@xxxxxxx>

Again, which case can trigger the issue ?
> ---
>  drivers/i2c/busses/i2c-imx-lpi2c.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/i2c/busses/i2c-imx-lpi2c.c
> b/drivers/i2c/busses/i2c-imx-lpi2c.c
> index 9db6ccded5e9..85b9c1fc7681 100644
> --- a/drivers/i2c/busses/i2c-imx-lpi2c.c
> +++ b/drivers/i2c/busses/i2c-imx-lpi2c.c
> @@ -260,8 +260,10 @@ static int lpi2c_imx_master_enable(struct
> lpi2c_imx_struct *lpi2c_imx)
>         int ret;
> 
>         ret = pm_runtime_get_sync(lpi2c_imx->adapter.dev.parent);
> -       if (ret < 0)
> +       if (ret < 0) {
> +               pm_runtime_put_noidle(lpi2c_imx->adapter.dev.parent);
>                 return ret;
> +       }
> 
>         temp = MCR_RST;
>         writel(temp, lpi2c_imx->base + LPI2C_MCR);
> --
> 2.17.1