Re: [RFT v2] mfd: exynos-lpass: Handle return value of clk_prepare_enable

[Marek Szyprowski]

Hi All,

On 2017-08-10 08:01, Krzysztof Kozlowski wrote:
> On Wed, Aug 09, 2017 at 10:18:10AM +0530, Arvind Yadav wrote:
> > clk_prepare_enable() can fail here and we must check its return value.
> > we must call pm_runtime_disable() and pm_runtime_set_suspended(),
> > If exynos_lpass_probe is not successful.
> >
> > Signed-off-by: Arvind Yadav <arvind.yadav.cs@xxxxxxxxx>
> > ---
> > changes in v2:
> >               added regmap_exit(lpass->top) and blank line before return.
> >
> >   drivers/mfd/exynos-lpass.c | 23 +++++++++++++++++------
> >   1 file changed, 17 insertions(+), 6 deletions(-)
> For me looks ok although this requires testing and I do not have
> Exynos with LPASS (e.g. Exynos5433). Maybe folks from Samsung (Polish
> R&D or HQ as they are working on it) could help (Cced).

Works fine on Exynos5433 based TM2e.

Tested-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>

> Best regards,
> Krzysztof
>
> > diff --git a/drivers/mfd/exynos-lpass.c b/drivers/mfd/exynos-lpass.c
> > index ca829f8..1ab7210 100644
> > --- a/drivers/mfd/exynos-lpass.c
> > +++ b/drivers/mfd/exynos-lpass.c
> > @@ -73,9 +73,13 @@ static void exynos_lpass_core_sw_reset(struct exynos_lpass *lpass, int mask)
> >   	regmap_write(lpass->top, SFR_LPASS_CORE_SW_RESET, val);
> >   }
> >   
> > -static void exynos_lpass_enable(struct exynos_lpass *lpass)
> > +static int exynos_lpass_enable(struct exynos_lpass *lpass)
> >   {
> > -	clk_prepare_enable(lpass->sfr0_clk);
> > +	int ret;
> > +
> > +	ret = clk_prepare_enable(lpass->sfr0_clk);
> > +	if (ret)
> > +		return ret;
> >   
> >   	/* Unmask SFR, DMA and I2S interrupt */
> >   	regmap_write(lpass->top, SFR_LPASS_INTR_CA5_MASK,
> > @@ -87,6 +91,8 @@ static void exynos_lpass_enable(struct exynos_lpass *lpass)
> >   	exynos_lpass_core_sw_reset(lpass, LPASS_I2S_SW_RESET);
> >   	exynos_lpass_core_sw_reset(lpass, LPASS_DMA_SW_RESET);
> >   	exynos_lpass_core_sw_reset(lpass, LPASS_MEM_SW_RESET);
> > +
> > +	return 0;
> >   }
> >   
> >   static void exynos_lpass_disable(struct exynos_lpass *lpass)
> > @@ -112,6 +118,7 @@ static int exynos_lpass_probe(struct platform_device *pdev)
> >   	struct exynos_lpass *lpass;
> >   	void __iomem *base_top;
> >   	struct resource *res;
> > +	int ret;
> >   
> >   	lpass = devm_kzalloc(dev, sizeof(*lpass), GFP_KERNEL);
> >   	if (!lpass)
> > @@ -136,7 +143,13 @@ static int exynos_lpass_probe(struct platform_device *pdev)
> >   	platform_set_drvdata(pdev, lpass);
> >   	pm_runtime_set_active(dev);
> >   	pm_runtime_enable(dev);
> > -	exynos_lpass_enable(lpass);
> > +	ret = exynos_lpass_enable(lpass);
> > +	if (ret) {
> > +		pm_runtime_disable(dev);
> > +		pm_runtime_set_suspended(dev);
> > +		regmap_exit(lpass->top);
> > +		return ret;
> > +	}
> >   
> >   	return devm_of_platform_populate(dev);
> >   }
> > @@ -167,9 +180,7 @@ static int __maybe_unused exynos_lpass_resume(struct device *dev)
> >   {
> >   	struct exynos_lpass *lpass = dev_get_drvdata(dev);
> >   
> > -	exynos_lpass_enable(lpass);
> > -
> > -	return 0;
> > +	return exynos_lpass_enable(lpass);
> >   }
> >   
> >   static const struct dev_pm_ops lpass_pm_ops = {
> > --
> > 1.9.1

Best regards
--
Marek Szyprowski, PhD
Samsung R&D Institute Poland