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author | Xenia Ragiadakou <burzalodowa@gmail.com> | 2013-08-14 05:55:19 +0300 |
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committer | Sarah Sharp <sarah.a.sharp@linux.intel.com> | 2013-08-13 21:16:42 -0700 |
commit | c10cf1189d7659ffd7dbe488a4cee7ec0dcdd9c6 (patch) | |
tree | eec5cbbdb43a74e0b74675732346a2dd2dc70fcb /drivers/usb/host/xhci-plat.c | |
parent | 68ffb01111500c769ceac055bdc2fb000322b2d7 (diff) | |
download | op-kernel-dev-c10cf1189d7659ffd7dbe488a4cee7ec0dcdd9c6.zip op-kernel-dev-c10cf1189d7659ffd7dbe488a4cee7ec0dcdd9c6.tar.gz |
xhci: fix dma mask setup in xhci.c
The function dma_set_mask() tests internally whether the dma_mask pointer
for the device is initialized and fails if the dma_mask pointer is NULL.
On pci platforms, the device dma_mask pointer is initialized, when pci
devices are enumerated, to point to the pci_dev->dma_mask which is 0xffffffff.
However, for non-pci platforms, the dma_mask pointer may not be initialized
and in that case dma_set_mask() will fail.
This patch initializes the dma_mask and the coherent_dma_mask to 32bits
in xhci_plat_probe(), before the call to usb_create_hcd() that sets the
"uses_dma" flag for the usb bus and the call to usb_add_hcd() that creates
coherent dma pools for the usb hcd.
Moreover, a call to dma_set_mask() does not set the device coherent_dma_mask.
Since the xhci-hcd driver calls dma_alloc_coherent() and dma_pool_alloc()
to allocate consistent DMA memory blocks, the coherent DMA address mask
has to be set explicitly.
This patch sets the coherent_dma_mask to 64bits in xhci_gen_setup() when
the xHC is capable for 64-bit DMA addressing.
If dma_set_mask() succeeds, for a given bitmask, it is guaranteed that
the given bitmask is also supported for consistent DMA mappings.
Other changes introduced in this patch are:
- The return value of dma_set_mask() is checked to ensure that the required
dma bitmask conforms with the host system's addressing capabilities.
- The dma_mask setup code for the non-primary hcd was removed since both
primary and non-primary hcd refer to the same generic device whose
dma_mask and coherent_dma_mask are already set during the setup of
the primary hcd.
- The code for reading the HCCPARAMS register to find out the addressing
capabilities of xHC was removed since its value is already cached in
xhci->hccparams.
- hcd->self.controller was replaced with the dev variable since it is
already available.
Signed-off-by: Xenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Diffstat (limited to 'drivers/usb/host/xhci-plat.c')
-rw-r--r-- | drivers/usb/host/xhci-plat.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c index 3fcdaea..be5e70d 100644 --- a/drivers/usb/host/xhci-plat.c +++ b/drivers/usb/host/xhci-plat.c @@ -15,6 +15,7 @@ #include <linux/module.h> #include <linux/slab.h> #include <linux/of.h> +#include <linux/dma-mapping.h> #include "xhci.h" @@ -105,6 +106,15 @@ static int xhci_plat_probe(struct platform_device *pdev) if (!res) return -ENODEV; + /* Initialize dma_mask and coherent_dma_mask to 32-bits */ + ret = dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(32)); + if (ret) + return ret; + if (!pdev->dev.dma_mask) + pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask; + else + dma_set_mask(&pdev->dev, DMA_BIT_MASK(32)); + hcd = usb_create_hcd(driver, &pdev->dev, dev_name(&pdev->dev)); if (!hcd) return -ENOMEM; |