[PATCH] clk: palmas: unprepare clock on provider registration failure

[PATCH] clk: palmas: unprepare clock on provider registration failure

[Myeonghun Pak]

palmas_clks_init_configure() prepares the clock when an external control
pin is configured.  If the subsequent of_clk_add_hw_provider() call fails,
palmas_clks_probe() returns the error without dropping that prepare
reference.

Unprepare the clock on that error path when external control is active, so
the probe failure path balances the successful clk_prepare().

This issue was identified during our ongoing static-analysis research while
reviewing kernel code.

Fixes: 942d1d674931 ("clk: Add driver for Palmas clk32kg and clk32kgaudio clocks")
Co-developed-by: Ijae Kim <ae878000@gmail.com>
Signed-off-by: Ijae Kim <ae878000@gmail.com>
Signed-off-by: Myeonghun Pak <mhun512@gmail.com>

---
 drivers/clk/clk-palmas.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/clk/clk-palmas.c b/drivers/clk/clk-palmas.c
index 39049f62db..ab9df2eedb 100644
--- a/drivers/clk/clk-palmas.c
+++ b/drivers/clk/clk-palmas.c
@@ -265,8 +265,11 @@ static int palmas_clks_probe(struct platform_device *pdev)
 	}
 
 	ret = of_clk_add_hw_provider(node, of_clk_hw_simple_get, &cinfo->hw);
-	if (ret < 0)
+	if (ret < 0) {
 		dev_err(&pdev->dev, "Fail to add clock driver, %d\n", ret);
+		if (cinfo->ext_control_pin)
+			clk_unprepare(cinfo->hw.clk);
+	}
 	return ret;
 }
 
-- 
2.47.1

Re: [PATCH] clk: palmas: unprepare clock on provider registration failure

[Brian Masney]

Hi Myeonghun,

Thanks for the patch!

On Tue, Jun 23, 2026 at 06:07:34PM +0900, Myeonghun Pak wrote:
> palmas_clks_init_configure() prepares the clock when an external control
> pin is configured.  If the subsequent of_clk_add_hw_provider() call fails,
> palmas_clks_probe() returns the error without dropping that prepare
> reference.
> 
> Unprepare the clock on that error path when external control is active, so
> the probe failure path balances the successful clk_prepare().
> 
> This issue was identified during our ongoing static-analysis research while
> reviewing kernel code.
> 
> Fixes: 942d1d674931 ("clk: Add driver for Palmas clk32kg and clk32kgaudio clocks")
> Co-developed-by: Ijae Kim <ae878000@gmail.com>
> Signed-off-by: Ijae Kim <ae878000@gmail.com>
> Signed-off-by: Myeonghun Pak <mhun512@gmail.com>
> 
> ---
>  drivers/clk/clk-palmas.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/clk/clk-palmas.c b/drivers/clk/clk-palmas.c
> index 39049f62db..ab9df2eedb 100644
> --- a/drivers/clk/clk-palmas.c
> +++ b/drivers/clk/clk-palmas.c
> @@ -265,8 +265,11 @@ static int palmas_clks_probe(struct platform_device *pdev)
>  	}
>  
>  	ret = of_clk_add_hw_provider(node, of_clk_hw_simple_get, &cinfo->hw);
> -	if (ret < 0)
> +	if (ret < 0) {
>  		dev_err(&pdev->dev, "Fail to add clock driver, %d\n", ret);
> +		if (cinfo->ext_control_pin)
> +			clk_unprepare(cinfo->hw.clk);
> +	}

The driver currently only calls clk_unprepare() on an error path in
palmas_clks_init_configure(). It leaks when the driver is removed.

I think the cleanest approach to fixing this is to convert over to use
devm_of_clk_add_hw_provider().

Brian