[PATCH] Enable the clock before calling clk_get_rate().

[PATCH] Enable the clock before calling clk_get_rate().

[Stefan Potyra]

Found by Linux Driver Verification project (linuxtesting.org).

Fixes: 142168eba9dc spi: bcm63xx-hsspi: add bcm63xx HSSPI driver
Signed-off-by: Stefan Potyra <Stefan.Potyra@elektrobit.com>
---
 drivers/spi/spi-bcm63xx-hsspi.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/spi/spi-bcm63xx-hsspi.c b/drivers/spi/spi-bcm63xx-hsspi.c
index cbcba614b253..46cd9b683d22 100644
--- a/drivers/spi/spi-bcm63xx-hsspi.c
+++ b/drivers/spi/spi-bcm63xx-hsspi.c
@@ -352,6 +352,10 @@ static int bcm63xx_hsspi_probe(struct platform_device *pdev)
 	if (IS_ERR(clk))
 		return PTR_ERR(clk);
 
+	ret = clk_prepare_enable(clk);
+	if (ret)
+		return ret;
+
 	rate = clk_get_rate(clk);
 	if (!rate) {
 		struct clk *pll_clk = devm_clk_get(dev, "pll");
@@ -364,10 +368,6 @@ static int bcm63xx_hsspi_probe(struct platform_device *pdev)
 			return -EINVAL;
 	}
 
-	ret = clk_prepare_enable(clk);
-	if (ret)
-		return ret;
-
 	master = spi_alloc_master(&pdev->dev, sizeof(*bs));
 	if (!master) {
 		ret = -ENOMEM;
-- 
2.17.0

[PATCH] Enable the clock before calling clk_get_rate().

[Florian Fainelli]

+Jonas,

On 04/19/2018 06:03 AM, Stefan Potyra wrote:
> Found by Linux Driver Verification project (linuxtesting.org).

Please use a commit subject which matches what was used before:

git log --no-merges --oneline drivers/spi/spi-bcm63xx-hsspi.c
378da4a65f3a spi/bcm63xx-hspi: fix error return code in
bcm63xx_hsspi_probe()
c3c25ea712c9 spi/bcm63xx-hspi: Fix checkpatch warnings
0b85a8421790 spi: bcm63xx-hsspi: Export OF device ID table as module aliases
7ab2463550e2 spi/bcm63xx-hsspi: allow for probing through devicetree
ff18e1ef04e2 spi/bcm63xx-hsspi: allow providing clock rate through a
second clock
f4d862237715 spi/bcm63xx-hsspi: add support for dual spi read/write
14ac00e033c5 spi: drop owner assignment from platform_drivers
e4745fef5595 spi: Remove unneeded include of linux/workqueue.h
1480916ebd6f spi: bcm63xx-hsspi: Use SIMPLE_DEV_PM_OPS macro
aa0fe82629f1 spi: Use reinit_completion at appropriate places
937ebf9cd34a spi/bcm63xx-hsspi: fix pm sleep support
7d255695804f spi/bcm63xx-hsspi: use devm_register_master()
dea5de1b37c0 spi/bcm63xx-hsspi: check result of clk_prepare_enable
b1bdd4f883e1 spi: bcm63xx-hsspi: Use devm_clk_get()
87917528cc92 spi: bcm63xx-hsspi: checking for ERR_PTR instead of NULL
142168eba9dc spi: bcm63xx-hsspi: add bcm63xx HSSPI driver

> 
> Fixes: 142168eba9dc spi: bcm63xx-hsspi: add bcm63xx HSSPI driver

Please include the commit title in ("<title>") as is indicated in the
SubmittingPatches document.

Thank you

> Signed-off-by: Stefan Potyra <Stefan.Potyra@elektrobit.com>
> ---
>  drivers/spi/spi-bcm63xx-hsspi.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/spi/spi-bcm63xx-hsspi.c b/drivers/spi/spi-bcm63xx-hsspi.c
> index cbcba614b253..46cd9b683d22 100644
> --- a/drivers/spi/spi-bcm63xx-hsspi.c
> +++ b/drivers/spi/spi-bcm63xx-hsspi.c
> @@ -352,6 +352,10 @@ static int bcm63xx_hsspi_probe(struct platform_device *pdev)
>  	if (IS_ERR(clk))
>  		return PTR_ERR(clk);
>  
> +	ret = clk_prepare_enable(clk);
> +	if (ret)
> +		return ret;
> +
>  	rate = clk_get_rate(clk);
>  	if (!rate) {
>  		struct clk *pll_clk = devm_clk_get(dev, "pll");
> @@ -364,10 +368,6 @@ static int bcm63xx_hsspi_probe(struct platform_device *pdev)
>  			return -EINVAL;
>  	}
>  
> -	ret = clk_prepare_enable(clk);
> -	if (ret)
> -		return ret;
> -
>  	master = spi_alloc_master(&pdev->dev, sizeof(*bs));
>  	if (!master) {
>  		ret = -ENOMEM;
> 

-- 
Florian

[PATCH v2] spi/bcm63xx-hspi: Enable the clock before calling clk_get_rate().

[Mark Brown]

On Tue, Apr 24, 2018 at 06:16:05PM +0200, Stefan Potyra wrote:

> +	ret = clk_prepare_enable(clk);
> +	if (ret)
> +		return ret;
> +
>  	rate = clk_get_rate(clk);
>  	if (!rate) {
>  		struct clk *pll_clk = devm_clk_get(dev, "pll");
> @@ -364,10 +368,6 @@ static int bcm63xx_hsspi_probe(struct platform_device *pdev)
>  			return -EINVAL;
>  	}
>  
> -	ret = clk_prepare_enable(clk);
> -	if (ret)
> -		return ret;
> -

We can return an error after the clock was enabled, this will leake the
clock if that happens.
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[PATCH v3] spi/bcm63xx-hspi: Enable the clock before calling

[Mark Brown]

On Wed, Apr 25, 2018 at 03:47:30PM +0200, Stefan Potyra wrote:

> +	ret = clk_prepare_enable(clk);
> +	if (ret)
> +		return ret;
> +
>  	rate = clk_get_rate(clk);
>  	if (!rate) {
>  		struct clk *pll_clk = devm_clk_get(dev, "pll");
>  
> -		if (IS_ERR(pll_clk))
> -			return PTR_ERR(pll_clk);
> +		if (IS_ERR(pll_clk)) {
> +			ret = PTR_ERR(pll_clk);
> +			goto out_disable_clk;
> +		}
> +
>  
>  		rate = clk_get_rate(pll_clk);

Isn't this just showing the same problem with not enabling the pll_clk
before getting the rate that you're trying to fix for the main clk?
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[PATCH v4] spi/bcm63xx-hspi: Enable the clock before calling clk_get_rate().

[Mark Brown]

On Wed, Apr 25, 2018 at 06:49:06PM +0200, Stefan Potyra wrote:

> Additionally, prepare/enable the pll_clk before calling clk_get_rate()
> for the same reason.

I don't see this change in the code:

>  		struct clk *pll_clk = devm_clk_get(dev, "pll");
>  
> -		if (IS_ERR(pll_clk))
> -			return PTR_ERR(pll_clk);
> +		if (IS_ERR(pll_clk)) {
> +			ret = PTR_ERR(pll_clk);
> +			goto out_disable_clk;
> +		}
> +
>  
>  		rate = clk_get_rate(pll_clk);
> -		if (!rate)
> -			return -EINVAL;

Did you forget a git add?
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