2017-07-24 17:42:11

by Robin Murphy

[permalink] [raw]
Subject: [PATCH] qtfnmac: Tidy up DMA mask setting

As the only caller of dma_supported() outside of DMA API internals, the
qtfnmac driver stands out and invites scrutiny. Thankfully, it's not
being used for evil, but it is entirely redundant, since it open-codes a
check that the DMA mask setting functions are going to perform anyway.
In fact, the whole qtnf_pcie_init_dma_mask() function is nothing more
than a rather long-winded implementation of dma_set_mask_and_coherent(),
so let's just use that directly.

Signed-off-by: Robin Murphy <[email protected]>
---
.../net/wireless/quantenna/qtnfmac/pearl/pcie.c | 28 +---------------------
1 file changed, 1 insertion(+), 27 deletions(-)

diff --git a/drivers/net/wireless/quantenna/qtnfmac/pearl/pcie.c b/drivers/net/wireless/quantenna/qtnfmac/pearl/pcie.c
index 7fc4f0d6a9ad..2c065ffda070 100644
--- a/drivers/net/wireless/quantenna/qtnfmac/pearl/pcie.c
+++ b/drivers/net/wireless/quantenna/qtnfmac/pearl/pcie.c
@@ -274,32 +274,6 @@ static int qtnf_pcie_init_memory(struct qtnf_pcie_bus_priv *priv)
return 0;
}

-static int
-qtnf_pcie_init_dma_mask(struct qtnf_pcie_bus_priv *priv, u64 dma_mask)
-{
- int ret;
-
- ret = dma_supported(&priv->pdev->dev, dma_mask);
- if (!ret) {
- pr_err("DMA mask %llu not supported\n", dma_mask);
- return ret;
- }
-
- ret = pci_set_dma_mask(priv->pdev, dma_mask);
- if (ret) {
- pr_err("failed to set DMA mask %llu\n", dma_mask);
- return ret;
- }
-
- ret = pci_set_consistent_dma_mask(priv->pdev, dma_mask);
- if (ret) {
- pr_err("failed to set consistent DMA mask %llu\n", dma_mask);
- return ret;
- }
-
- return ret;
-}
-
static void qtnf_tune_pcie_mps(struct qtnf_pcie_bus_priv *priv)
{
struct pci_dev *pdev = priv->pdev;
@@ -1212,7 +1186,7 @@ static int qtnf_pcie_probe(struct pci_dev *pdev, const struct pci_device_id *id)
goto err_base;
}

- ret = qtnf_pcie_init_dma_mask(pcie_priv, DMA_BIT_MASK(32));
+ ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
if (ret) {
pr_err("PCIE DMA mask init failed\n");
goto err_base;
--
2.12.2.dirty


2017-07-25 22:01:09

by Sergey Matyukevich

[permalink] [raw]
Subject: Re: [PATCH] qtfnmac: Tidy up DMA mask setting

> As the only caller of dma_supported() outside of DMA API internals, the
> qtfnmac driver stands out and invites scrutiny. Thankfully, it's not
> being used for evil, but it is entirely redundant, since it open-codes a
> check that the DMA mask setting functions are going to perform anyway.
> In fact, the whole qtnf_pcie_init_dma_mask() function is nothing more
> than a rather long-winded implementation of dma_set_mask_and_coherent(),
> so let's just use that directly.
>
> Signed-off-by: Robin Murphy <[email protected]>


Nice, thanks you !

Acked-by: Sergey Matyukevich <[email protected]>

2017-08-03 09:57:39

by Kalle Valo

[permalink] [raw]
Subject: Re: qtfnmac: Tidy up DMA mask setting

Robin Murphy <[email protected]> wrote:

> As the only caller of dma_supported() outside of DMA API internals, the
> qtfnmac driver stands out and invites scrutiny. Thankfully, it's not
> being used for evil, but it is entirely redundant, since it open-codes a
> check that the DMA mask setting functions are going to perform anyway.
> In fact, the whole qtnf_pcie_init_dma_mask() function is nothing more
> than a rather long-winded implementation of dma_set_mask_and_coherent(),
> so let's just use that directly.
>
> Signed-off-by: Robin Murphy <[email protected]>
> Acked-by: Sergey Matyukevich <[email protected]>

There's a typo in title prefix, I'll fix it to "qtnfmac:".

--
https://patchwork.kernel.org/patch/9859961/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches

2017-08-03 10:01:15

by Kalle Valo

[permalink] [raw]
Subject: Re: qtnfmac: Tidy up DMA mask setting

Robin Murphy <[email protected]> wrote:

> As the only caller of dma_supported() outside of DMA API internals, the
> qtfnmac driver stands out and invites scrutiny. Thankfully, it's not
> being used for evil, but it is entirely redundant, since it open-codes a
> check that the DMA mask setting functions are going to perform anyway.
> In fact, the whole qtnf_pcie_init_dma_mask() function is nothing more
> than a rather long-winded implementation of dma_set_mask_and_coherent(),
> so let's just use that directly.
>
> Signed-off-by: Robin Murphy <[email protected]>
> Acked-by: Sergey Matyukevich <[email protected]>

Patch applied to wireless-drivers-next.git, thanks.

13cb8a5845ff qtnfmac: Tidy up DMA mask setting

--
https://patchwork.kernel.org/patch/9859961/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches