RE: [EXT] [PATCH] [v3] i2c: imx-lpi2c: Fix runtime PM imbalance on error

[Andy Duan <fugang.duan@nxp.com>]

From: Dinghao Liu <dinghao.liu@zju.edu.cn> Sent: Monday, June 1, 2020 2:17 PM
> pm_runtime_get_sync() increments the runtime PM usage counter even the
> call returns an error code. Thus a corresponding decrement is needed on the
> error handling path to keep the counter balanced.
> 
> Fix this by adding the missed function call.
> 
> Fixes: 13d6eb20fc79a ("i2c: imx-lpi2c: add runtime pm support")
> Co-developed-by: Markus Elfring <Markus.Elfring@web.de>
> Signed-off-by: Markus Elfring <Markus.Elfring@web.de>
> Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn>

Reviewed-by: Fugang Duan <fugang.duan@nxp.com>
> ---
> 
> Changelog:
> 
> v2: - Use pm_runtime_put_noidle() instead of
>       pm_runtime_put_autosuspend().
> 
> v3: - Refine commit message.
> ---
>  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 94743ba581fe..bdee02dff284 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