diff options
Diffstat (limited to 'drivers/usb/core/hcd.c')
| -rw-r--r-- | drivers/usb/core/hcd.c | 17 |
1 files changed, 14 insertions, 3 deletions
diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c index 06eea8848ccc..4db3add28b44 100644 --- a/drivers/usb/core/hcd.c +++ b/drivers/usb/core/hcd.c @@ -1251,7 +1251,8 @@ void usb_hcd_unlink_urb_from_ep(struct usb_hcd *hcd, struct urb *urb) EXPORT_SYMBOL_GPL(usb_hcd_unlink_urb_from_ep); /* - * Some usb host controllers can only perform dma using a small SRAM area. + * Some usb host controllers can only perform dma using a small SRAM area, + * or have restrictions on addressable DRAM. * The usb core itself is however optimized for host controllers that can dma * using regular system memory - like pci devices doing bus mastering. * @@ -3117,8 +3118,18 @@ int usb_hcd_setup_local_mem(struct usb_hcd *hcd, phys_addr_t phys_addr, if (IS_ERR(hcd->localmem_pool)) return PTR_ERR(hcd->localmem_pool); - local_mem = devm_memremap(hcd->self.sysdev, phys_addr, - size, MEMREMAP_WC); + /* + * if a physical SRAM address was passed, map it, otherwise + * allocate system memory as a buffer. + */ + if (phys_addr) + local_mem = devm_memremap(hcd->self.sysdev, phys_addr, + size, MEMREMAP_WC); + else + local_mem = dmam_alloc_attrs(hcd->self.sysdev, size, &dma, + GFP_KERNEL, + DMA_ATTR_WRITE_COMBINE); + if (IS_ERR(local_mem)) return PTR_ERR(local_mem); |