Re: [PATCH] clk: imx: scu: Fix pm_runtime_get_sync() error checking

From: Stephen Boyd <sboyd@kernel.org>
To: Abel Vesa <abel.vesa@nxp.com>,
	Dong Aisheng <aisheng.dong@nxp.com>,
	Fabio Estevam <festevam@gmail.com>,
	Miaoqian Lin <linmq006@gmail.com>,
	Michael Turquette <mturquette@baylibre.com>,
	NXP Linux Team <linux-imx@nxp.com>,
	Pengutronix Kernel Team <kernel@pengutronix.de>,
	Sascha Hauer <s.hauer@pengutronix.de>,
	Shawn Guo <shawnguo@kernel.org>,
	linux-arm-kernel@lists.infradead.org, linux-clk@vger.kernel.org,
	linux-kernel@vger.kernel.org
Cc: linmq006@gmail.com
Subject: Re: [PATCH] clk: imx: scu: Fix pm_runtime_get_sync() error checking
Date: Thu, 21 Apr 2022 18:20:57 -0700	[thread overview]
Message-ID: <20220422012059.52267C385A5@smtp.kernel.org> (raw)
In-Reply-To: <20220412065719.17735-1-linmq006@gmail.com>

Quoting Miaoqian Lin (2022-04-11 23:57:18)
> If the device is already in a runtime PM enabled state
> pm_runtime_get_sync() will return 1, so a test for negative
> value should be used to check for errors.

Maybe it should use pm_runtime_resume_and_get() instead?

> 
> Fixes: 78edeb080330 ("clk: imx: scu: add runtime pm support")
> Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
> ---
>  drivers/clk/imx/clk-scu.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/clk/imx/clk-scu.c b/drivers/clk/imx/clk-scu.c
> index 083da31dc3ea..18c6190eeffd 100644
> --- a/drivers/clk/imx/clk-scu.c
> +++ b/drivers/clk/imx/clk-scu.c
> @@ -529,7 +529,7 @@ static int imx_clk_scu_probe(struct platform_device *pdev)
>                 pm_runtime_enable(dev);
>  
>                 ret = pm_runtime_get_sync(dev);
> -               if (ret) {
> +               if (ret < 0) {
>                         pm_genpd_remove_device(dev);
>                         pm_runtime_disable(dev);
>                         return ret;
> -- 
> 2.17.1
>