[PATCH v2] crypto: ccree - Remove a useless dma_supported() call

[PATCH v2] crypto: ccree - Remove a useless dma_supported() call

[Christophe JAILLET]

There is no point in calling dma_supported() before calling
dma_set_coherent_mask(). This function already calls dma_supported() and
returns an error (-EIO) if it fails.

So remove the superfluous dma_supported() call.

Moreover, setting a larger DMA mask will never fail when setting a smaller
one will succeed, so the whole "while" loop can be removed as well. (see
[1])

While at it, fix the name of the function reported in a dev_err().

[1]: https://lore.kernel.org/all/YteQ6Vx2C03UtCkG@infradead.org/

Suggested-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
---
 drivers/crypto/ccree/cc_driver.c | 13 +++----------
 1 file changed, 3 insertions(+), 10 deletions(-)

diff --git a/drivers/crypto/ccree/cc_driver.c b/drivers/crypto/ccree/cc_driver.c
index 7d1bee86d581..cadead18b59e 100644
--- a/drivers/crypto/ccree/cc_driver.c
+++ b/drivers/crypto/ccree/cc_driver.c
@@ -372,17 +372,10 @@ static int init_cc_resources(struct platform_device *plat_dev)
 		dev->dma_mask = &dev->coherent_dma_mask;
 
 	dma_mask = DMA_BIT_MASK(DMA_BIT_MASK_LEN);
-	while (dma_mask > 0x7fffffffUL) {
-		if (dma_supported(dev, dma_mask)) {
-			rc = dma_set_coherent_mask(dev, dma_mask);
-			if (!rc)
-				break;
-		}
-		dma_mask >>= 1;
-	}
-
+	rc = dma_set_coherent_mask(dev, dma_mask);
 	if (rc) {
-		dev_err(dev, "Failed in dma_set_mask, mask=%llx\n", dma_mask);
+		dev_err(dev, "Failed in dma_set_coherent_mask, mask=%llx\n",
+			dma_mask);
 		return rc;
 	}
 
-- 
2.34.1

Re: [PATCH v2] crypto: ccree - Remove a useless dma_supported() call

[Gilad Ben-Yossef]

Hi,


On Wed, Jul 20, 2022 at 4:29 PM Christophe JAILLET
<christophe.jaillet@wanadoo.fr> wrote:
>
> There is no point in calling dma_supported() before calling
> dma_set_coherent_mask(). This function already calls dma_supported() and
> returns an error (-EIO) if it fails.
>
> So remove the superfluous dma_supported() call.
>
> Moreover, setting a larger DMA mask will never fail when setting a smaller
> one will succeed, so the whole "while" loop can be removed as well. (see
> [1])
>
> While at it, fix the name of the function reported in a dev_err().
>
> [1]: https://lore.kernel.org/all/YteQ6Vx2C03UtCkG@infradead.org/
>
> Suggested-by: Christoph Hellwig <hch@infradead.org>
> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
> ---
>  drivers/crypto/ccree/cc_driver.c | 13 +++----------
>  1 file changed, 3 insertions(+), 10 deletions(-)

Acked-by: Gilad Ben-Yossef <gilad@benyossef.com>

Thank you,
Gilad

>
> diff --git a/drivers/crypto/ccree/cc_driver.c b/drivers/crypto/ccree/cc_driver.c
> index 7d1bee86d581..cadead18b59e 100644
> --- a/drivers/crypto/ccree/cc_driver.c
> +++ b/drivers/crypto/ccree/cc_driver.c
> @@ -372,17 +372,10 @@ static int init_cc_resources(struct platform_device *plat_dev)
>                 dev->dma_mask = &dev->coherent_dma_mask;
>
>         dma_mask = DMA_BIT_MASK(DMA_BIT_MASK_LEN);
> -       while (dma_mask > 0x7fffffffUL) {
> -               if (dma_supported(dev, dma_mask)) {
> -                       rc = dma_set_coherent_mask(dev, dma_mask);
> -                       if (!rc)
> -                               break;
> -               }
> -               dma_mask >>= 1;
> -       }
> -
> +       rc = dma_set_coherent_mask(dev, dma_mask);
>         if (rc) {
> -               dev_err(dev, "Failed in dma_set_mask, mask=%llx\n", dma_mask);
> +               dev_err(dev, "Failed in dma_set_coherent_mask, mask=%llx\n",
> +                       dma_mask);
>                 return rc;
>         }
>
> --
> 2.34.1
>


-- 
Gilad Ben-Yossef
Chief Coffee Drinker

values of β will give rise to dom!

Re: [PATCH v2] crypto: ccree - Remove a useless dma_supported() call

[Herbert Xu]

On Wed, Jul 20, 2022 at 03:28:44PM +0200, Christophe JAILLET wrote:
> There is no point in calling dma_supported() before calling
> dma_set_coherent_mask(). This function already calls dma_supported() and
> returns an error (-EIO) if it fails.
> 
> So remove the superfluous dma_supported() call.
> 
> Moreover, setting a larger DMA mask will never fail when setting a smaller
> one will succeed, so the whole "while" loop can be removed as well. (see
> [1])
> 
> While at it, fix the name of the function reported in a dev_err().
> 
> [1]: https://lore.kernel.org/all/YteQ6Vx2C03UtCkG@infradead.org/
> 
> Suggested-by: Christoph Hellwig <hch@infradead.org>
> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
> ---
>  drivers/crypto/ccree/cc_driver.c | 13 +++----------
>  1 file changed, 3 insertions(+), 10 deletions(-)

Patch applied.  Thanks.
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt