On Mon, Sep 23, 2013 at 03:55:33PM +0530, Vinod Koul wrote:
> On Fri, Sep 20, 2013 at 12:15:39AM +0100, Russell King wrote:
> > register_platform_device_full() can setup the DMA mask provided the
> > appropriate member is set in struct platform_device_info. So lets
> > make that be the case. This avoids a direct reference to the DMA
> > masks by this driver.
> >
> > Signed-off-by: Russell King <rmk+kernel@xxxxxxxxxxxxxxxx>
> Acked-by: Vinod Koul <vinod.koul@xxxxxxxxx>
>
> This also brings me question that should we force the driver to use the
> dma_set_mask_and_coherent() API or they have below flexiblity too?
There's two issues here:
1. dma_set_mask_and_coherent() will only work if dev->dma_mask points at
some storage for the mask. This needs to have .dma_mask in the
platform_device_info initialised.
2. Yes, this driver should also be calling the appropriate DMA mask setting
functions in addition to having the mask initialized at device creation
time.
Here's a replacement patch, though maybe it would be better to roll all
the additions of dma_set_mask_and_coherent() in drivers/dma into one
patch? In other words, combine the addition of this with these two
patches:
dma: pl330: add dma_set_mask_and_coherent() call
dma: pl08x: add dma_set_mask_and_coherent() call
8<=====
From: Russell King <rmk+kernel@xxxxxxxxxxxxxxxx>
Subject: [PATCH] DMA-API: dma: edma.c: no need to explicitly initialize DMA
masks
register_platform_device_full() can setup the DMA mask provided the
appropriate member is set in struct platform_device_info. So lets
make that be the case. This avoids a direct reference to the DMA
masks by this driver.
While here, add the dma_set_mask_and_coherent() call which the DMA API
requires DMA-using drivers to call.
Signed-off-by: Russell King <rmk+kernel@xxxxxxxxxxxxxxxx>
---
drivers/dma/edma.c | 10 ++++++----
1 files changed, 6 insertions(+), 4 deletions(-)
diff --git a/drivers/dma/edma.c b/drivers/dma/edma.c
index ff50ff4..fd5e48c 100644
--- a/drivers/dma/edma.c
+++ b/drivers/dma/edma.c
@@ -631,6 +631,10 @@ static int edma_probe(struct platform_device *pdev)
struct edma_cc *ecc;
int ret;
+ ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
+ if (ret)
+ return ret;
+
ecc = devm_kzalloc(&pdev->dev, sizeof(*ecc), GFP_KERNEL);
if (!ecc) {
dev_err(&pdev->dev, "Can't allocate controller\n");
@@ -702,11 +706,13 @@ static struct platform_device *pdev0, *pdev1;
static const struct platform_device_info edma_dev_info0 = {
.name = "edma-dma-engine",
.id = 0,
+ .dma_mask = DMA_BIT_MASK(32),
};
static const struct platform_device_info edma_dev_info1 = {
.name = "edma-dma-engine",
.id = 1,
+ .dma_mask = DMA_BIT_MASK(32),
};
static int edma_init(void)
@@ -720,8 +726,6 @@ static int edma_init(void)
ret = PTR_ERR(pdev0);
goto out;
}
- pdev0->dev.dma_mask = &pdev0->dev.coherent_dma_mask;
- pdev0->dev.coherent_dma_mask = DMA_BIT_MASK(32);
}
if (EDMA_CTLRS == 2) {
@@ -731,8 +735,6 @@ static int edma_init(void)
platform_device_unregister(pdev0);
ret = PTR_ERR(pdev1);
}
- pdev1->dev.dma_mask = &pdev1->dev.coherent_dma_mask;
- pdev1->dev.coherent_dma_mask = DMA_BIT_MASK(32);
}
out:
--
1.7.4.4
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