From mboxrd@z Thu Jan 1 00:00:00 1970 From: b.zolnierkie@samsung.com (Bartlomiej Zolnierkiewicz) Date: Tue, 10 Jan 2017 13:05:58 +0100 Subject: [PATCH] usb: dwc3-exynos fix unspecified suspend clk error handling In-Reply-To: <20170110022131.31042-1-shuahkh@osg.samsung.com> References: <20170110022131.31042-1-shuahkh@osg.samsung.com> Message-ID: <1641038.u0riMiuGF5@amdc3058> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi, On Monday, January 09, 2017 07:21:31 PM Shuah Khan wrote: > Fix dwc3_exynos_probe() to call clk_prepare_enable() only when suspend > clock is specified. Call clk_disable_unprepare() from remove and probe > error path only when susp_clk has been set from remove and probe error > paths. It is legal to call clk_prepare_enable() and clk_disable_unprepare() for NULL clock. Also your patch changes susp_clk handling while leaves axius_clk handling (which also can be NULL) untouched. Do you actually see some runtime problem with the current code? If not then the patch should probably be dropped. Best regards, -- Bartlomiej Zolnierkiewicz Samsung R&D Institute Poland Samsung Electronics > Signed-off-by: Shuah Khan > --- > drivers/usb/dwc3/dwc3-exynos.c | 10 ++++++---- > 1 file changed, 6 insertions(+), 4 deletions(-) > > diff --git a/drivers/usb/dwc3/dwc3-exynos.c b/drivers/usb/dwc3/dwc3-exynos.c > index e27899b..f97a3d7 100644 > --- a/drivers/usb/dwc3/dwc3-exynos.c > +++ b/drivers/usb/dwc3/dwc3-exynos.c > @@ -131,8 +131,8 @@ static int dwc3_exynos_probe(struct platform_device *pdev) > if (IS_ERR(exynos->susp_clk)) { > dev_info(dev, "no suspend clk specified\n"); > exynos->susp_clk = NULL; > - } > - clk_prepare_enable(exynos->susp_clk); > + } else > + clk_prepare_enable(exynos->susp_clk); > > if (of_device_is_compatible(node, "samsung,exynos7-dwusb3")) { > exynos->axius_clk = devm_clk_get(dev, "usbdrd30_axius_clk"); > @@ -196,7 +196,8 @@ static int dwc3_exynos_probe(struct platform_device *pdev) > regulator_disable(exynos->vdd33); > err2: > clk_disable_unprepare(exynos->axius_clk); > - clk_disable_unprepare(exynos->susp_clk); > + if (exynos->susp_clk) > + clk_disable_unprepare(exynos->susp_clk); > clk_disable_unprepare(exynos->clk); > return ret; > } > @@ -210,7 +211,8 @@ static int dwc3_exynos_remove(struct platform_device *pdev) > platform_device_unregister(exynos->usb3_phy); > > clk_disable_unprepare(exynos->axius_clk); > - clk_disable_unprepare(exynos->susp_clk); > + if (exynos->susp_clk) > + clk_disable_unprepare(exynos->susp_clk); > clk_disable_unprepare(exynos->clk); > > regulator_disable(exynos->vdd33);