2021-05-21 20:23:14

by Christophe JAILLET

[permalink] [raw]
Subject: [PATCH] usb: dwc3: meson-g12a: Disable the regulator in the error handling path of the probe

If an error occurs after a successful 'regulator_enable()' call,
'regulator_disable()' must be called.

Fix the error handling path of the probe accordingly.

The remove function doesn't need to be fixed, because the
'regulator_disable()' call is already hidden in 'dwc3_meson_g12a_suspend()'
which is called via 'pm_runtime_set_suspended()' in the remove function.

Fixes: c99993376f72 ("usb: dwc3: Add Amlogic G12A DWC3 glue")
Signed-off-by: Christophe JAILLET <[email protected]>
---
Please review carefully.

I'm not that sure about:
The remove function doesn't need to be fixed, because the
'regulator_disable()' call is already hidden in 'dwc3_meson_g12a_suspend()'
which is called via 'pm_runtime_set_suspended()' in the remove function.

This is more a guess than anything else!
---
drivers/usb/dwc3/dwc3-meson-g12a.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/dwc3/dwc3-meson-g12a.c b/drivers/usb/dwc3/dwc3-meson-g12a.c
index bdf1f98dfad8..804957525130 100644
--- a/drivers/usb/dwc3/dwc3-meson-g12a.c
+++ b/drivers/usb/dwc3/dwc3-meson-g12a.c
@@ -772,13 +772,13 @@ static int dwc3_meson_g12a_probe(struct platform_device *pdev)

ret = priv->drvdata->usb_init(priv);
if (ret)
- goto err_disable_clks;
+ goto err_disable_regulator;

/* Init PHYs */
for (i = 0 ; i < PHY_COUNT ; ++i) {
ret = phy_init(priv->phys[i]);
if (ret)
- goto err_disable_clks;
+ goto err_disable_regulator;
}

/* Set PHY Power */
@@ -816,6 +816,10 @@ static int dwc3_meson_g12a_probe(struct platform_device *pdev)
for (i = 0 ; i < PHY_COUNT ; ++i)
phy_exit(priv->phys[i]);

+err_disable_regulator:
+ if (priv->vbus)
+ regulator_disable(priv->vbus);
+
err_disable_clks:
clk_bulk_disable_unprepare(priv->drvdata->num_clks,
priv->drvdata->clks);
--
2.30.2


2021-05-23 16:05:21

by Martin Blumenstingl

[permalink] [raw]
Subject: Re: [PATCH] usb: dwc3: meson-g12a: Disable the regulator in the error handling path of the probe

Hi Christophe,

On Fri, May 21, 2021 at 6:55 PM Christophe JAILLET
<[email protected]> wrote:
>
> If an error occurs after a successful 'regulator_enable()' call,
> 'regulator_disable()' must be called.
>
> Fix the error handling path of the probe accordingly.
>
> The remove function doesn't need to be fixed, because the
> 'regulator_disable()' call is already hidden in 'dwc3_meson_g12a_suspend()'
> which is called via 'pm_runtime_set_suspended()' in the remove function.
>
> Fixes: c99993376f72 ("usb: dwc3: Add Amlogic G12A DWC3 glue")
> Signed-off-by: Christophe JAILLET <[email protected]>
for me this makes sense so:
Reviewed-by: Martin Blumenstingl <[email protected]>

> ---
> Please review carefully.
>
> I'm not that sure about:
> The remove function doesn't need to be fixed, because the
> 'regulator_disable()' call is already hidden in 'dwc3_meson_g12a_suspend()'
> which is called via 'pm_runtime_set_suspended()' in the remove function.
>
> This is more a guess than anything else!
I am not 100% sure about the suspend code-path, so I am hoping that
someone else (for example Neil) can also review your patch


Best regards,
Martin

2021-06-01 08:49:03

by Neil Armstrong

[permalink] [raw]
Subject: Re: [PATCH] usb: dwc3: meson-g12a: Disable the regulator in the error handling path of the probe

On 23/05/2021 18:03, Martin Blumenstingl wrote:
> Hi Christophe,
>
> On Fri, May 21, 2021 at 6:55 PM Christophe JAILLET
> <[email protected]> wrote:
>>
>> If an error occurs after a successful 'regulator_enable()' call,
>> 'regulator_disable()' must be called.
>>
>> Fix the error handling path of the probe accordingly.
>>
>> The remove function doesn't need to be fixed, because the
>> 'regulator_disable()' call is already hidden in 'dwc3_meson_g12a_suspend()'
>> which is called via 'pm_runtime_set_suspended()' in the remove function.
>>
>> Fixes: c99993376f72 ("usb: dwc3: Add Amlogic G12A DWC3 glue")
>> Signed-off-by: Christophe JAILLET <[email protected]>
> for me this makes sense so:
> Reviewed-by: Martin Blumenstingl <[email protected]>

Acked-by: Neil Armstrong <[email protected]>

>
>> ---
>> Please review carefully.
>>
>> I'm not that sure about:
>> The remove function doesn't need to be fixed, because the
>> 'regulator_disable()' call is already hidden in 'dwc3_meson_g12a_suspend()'
>> which is called via 'pm_runtime_set_suspended()' in the remove function.
>>
>> This is more a guess than anything else!
> I am not 100% sure about the suspend code-path, so I am hoping that
> someone else (for example Neil) can also review your patch

Not 100% sure aswell, but the probe function is wrong anyway and must be fixed by this patch, so LGTM.

Neil

>
>
> Best regards,
> Martin
>