[PATCH 04/20] i2c: viai2c-wmt: Fix clock leak in wmt_i2c_probe()

[PATCH 04/20] i2c: viai2c-wmt: Fix clock leak in wmt_i2c_probe()

[Wentao Liang]

In wmt_i2c_probe(), i2c->clk is acquired using of_clk_get(). If any
subsequent operation fails or when the module is unloaded, the clock
reference count is never decremented via clk_put(), leading to a
resource leak.

Switch to devm_clk_get() so that the clock is automatically managed
and released.

Fixes: 560746eb79d3 ("i2c: vt8500: Add support for I2C bus on Wondermedia SoCs")
Cc: stable@vger.kernel.org
Signed-off-by: Wentao Liang <vulab@iscas.ac.cn>
---
 drivers/i2c/busses/i2c-viai2c-wmt.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/i2c/busses/i2c-viai2c-wmt.c b/drivers/i2c/busses/i2c-viai2c-wmt.c
index 2cf3cc0165fb..74ca93b44347 100644
--- a/drivers/i2c/busses/i2c-viai2c-wmt.c
+++ b/drivers/i2c/busses/i2c-viai2c-wmt.c
@@ -117,7 +117,7 @@ static int wmt_i2c_probe(struct platform_device *pdev)
 		return dev_err_probe(&pdev->dev, err,
 				"failed to request irq %i\n", i2c->irq);
 
-	i2c->clk = of_clk_get(np, 0);
+	i2c->clk = devm_clk_get(&pdev->dev, NULL);
 	if (IS_ERR(i2c->clk))
 		return dev_err_probe(&pdev->dev, PTR_ERR(i2c->clk),
 				     "unable to request clock\n");
-- 
2.34.1

Re: [PATCH 04/20] i2c: viai2c-wmt: Fix clock leak in wmt_i2c_probe()

[Alexey Charkov]

On Wed, Sep 16, 2026 at 11:07 AM Wentao Liang <vulab@iscas.ac.cn> wrote:
>
> In wmt_i2c_probe(), i2c->clk is acquired using of_clk_get(). If any
> subsequent operation fails or when the module is unloaded, the clock
> reference count is never decremented via clk_put(), leading to a
> resource leak.
>
> Switch to devm_clk_get() so that the clock is automatically managed
> and released.
>
> Fixes: 560746eb79d3 ("i2c: vt8500: Add support for I2C bus on Wondermedia SoCs")
> Cc: stable@vger.kernel.org
> Signed-off-by: Wentao Liang <vulab@iscas.ac.cn>
> ---
>  drivers/i2c/busses/i2c-viai2c-wmt.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/i2c/busses/i2c-viai2c-wmt.c b/drivers/i2c/busses/i2c-viai2c-wmt.c
> index 2cf3cc0165fb..74ca93b44347 100644
> --- a/drivers/i2c/busses/i2c-viai2c-wmt.c
> +++ b/drivers/i2c/busses/i2c-viai2c-wmt.c
> @@ -117,7 +117,7 @@ static int wmt_i2c_probe(struct platform_device *pdev)
>                 return dev_err_probe(&pdev->dev, err,
>                                 "failed to request irq %i\n", i2c->irq);
>
> -       i2c->clk = of_clk_get(np, 0);
> +       i2c->clk = devm_clk_get(&pdev->dev, NULL);

Maybe we could go for devm_clk_get_enabled and drop some more
boilerplate which follows in wmt_i2c_reset_hardware, while at it?

Backporting this to stable seems like a stretch to me, though (it's
quite old code, so there would be quite a lot of backporting for a
rarely hit resource leak).

Best regards,
Alexey

Re: [PATCH 04/20] i2c: viai2c-wmt: Fix clock leak in wmt_i2c_probe()

[Andi Shyti]

Hi Wentao,

On Wed, Sep 16, 2026 at 11:17:49AM +0400, Alexey Charkov wrote:
> On Wed, Sep 16, 2026 at 11:07 AM Wentao Liang <vulab@iscas.ac.cn> wrote:
> >
> > In wmt_i2c_probe(), i2c->clk is acquired using of_clk_get(). If any
> > subsequent operation fails or when the module is unloaded, the clock
> > reference count is never decremented via clk_put(), leading to a
> > resource leak.
> >
> > Switch to devm_clk_get() so that the clock is automatically managed
> > and released.
> >
> > Fixes: 560746eb79d3 ("i2c: vt8500: Add support for I2C bus on Wondermedia SoCs")
> > Cc: stable@vger.kernel.org
> > Signed-off-by: Wentao Liang <vulab@iscas.ac.cn>

this is 4/20 but where are the rest of the patches?

> > ---
> >  drivers/i2c/busses/i2c-viai2c-wmt.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/i2c/busses/i2c-viai2c-wmt.c b/drivers/i2c/busses/i2c-viai2c-wmt.c
> > index 2cf3cc0165fb..74ca93b44347 100644
> > --- a/drivers/i2c/busses/i2c-viai2c-wmt.c
> > +++ b/drivers/i2c/busses/i2c-viai2c-wmt.c
> > @@ -117,7 +117,7 @@ static int wmt_i2c_probe(struct platform_device *pdev)
> >                 return dev_err_probe(&pdev->dev, err,
> >                                 "failed to request irq %i\n", i2c->irq);
> >
> > -       i2c->clk = of_clk_get(np, 0);
> > +       i2c->clk = devm_clk_get(&pdev->dev, NULL);
> 
> Maybe we could go for devm_clk_get_enabled and drop some more
> boilerplate which follows in wmt_i2c_reset_hardware, while at it?
> 
> Backporting this to stable seems like a stretch to me, though (it's
> quite old code, so there would be quite a lot of backporting for a
> rarely hit resource leak).

Alexey asked a question. Wouldn't it be good to follow up?

Unfortunately, this is becoming quite common with LLM generated
patches, where questions are often left unanswered, perhaps
because the patches are not fully understood by committers.

I think the patch is correct, though, and Alexey's suggestions
can be addressed after this is merged.

With some disappointment, I'm pushing this patch to
i2c/i2c-fixes-2.

Andi