diff options
Diffstat (limited to 'drivers/usb/core/hcd.c')
| -rw-r--r-- | drivers/usb/core/hcd.c | 51 |
1 files changed, 42 insertions, 9 deletions
diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c index 94d22551fc1b..88533938ce19 100644 --- a/drivers/usb/core/hcd.c +++ b/drivers/usb/core/hcd.c @@ -29,6 +29,8 @@ #include <linux/workqueue.h> #include <linux/pm_runtime.h> #include <linux/types.h> +#include <linux/genalloc.h> +#include <linux/io.h> #include <linux/phy/phy.h> #include <linux/usb.h> @@ -1345,14 +1347,14 @@ EXPORT_SYMBOL_GPL(usb_hcd_unlink_urb_from_ep); * using regular system memory - like pci devices doing bus mastering. * * To support host controllers with limited dma capabilities we provide dma - * bounce buffers. This feature can be enabled using the HCD_LOCAL_MEM flag. + * bounce buffers. This feature can be enabled by initializing + * hcd->localmem_pool using usb_hcd_setup_local_mem(). * For this to work properly the host controller code must first use the * function dma_declare_coherent_memory() to point out which memory area * that should be used for dma allocations. * - * The HCD_LOCAL_MEM flag then tells the usb code to allocate all data for - * dma using dma_alloc_coherent() which in turn allocates from the memory - * area pointed out with dma_declare_coherent_memory(). + * The initialized hcd->localmem_pool then tells the usb code to allocate all + * data for dma using the genalloc API. * * So, to summarize... * @@ -1362,9 +1364,6 @@ EXPORT_SYMBOL_GPL(usb_hcd_unlink_urb_from_ep); * (a) "normal" kernel memory is no good, and * (b) there's not enough to share * - * - The only *portable* hook for such stuff in the - * DMA framework is dma_declare_coherent_memory() - * * - So we use that, even though the primary requirement * is that the memory be "local" (hence addressable * by that device), not "coherent". @@ -1531,7 +1530,7 @@ int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb, urb->setup_dma)) return -EAGAIN; urb->transfer_flags |= URB_SETUP_MAP_SINGLE; - } else if (hcd->driver->flags & HCD_LOCAL_MEM) { + } else if (hcd->localmem_pool) { ret = hcd_alloc_coherent( urb->dev->bus, mem_flags, &urb->setup_dma, @@ -1601,7 +1600,7 @@ int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb, else urb->transfer_flags |= URB_DMA_MAP_SINGLE; } - } else if (hcd->driver->flags & HCD_LOCAL_MEM) { + } else if (hcd->localmem_pool) { ret = hcd_alloc_coherent( urb->dev->bus, mem_flags, &urb->transfer_dma, @@ -3039,6 +3038,40 @@ usb_hcd_platform_shutdown(struct platform_device *dev) } EXPORT_SYMBOL_GPL(usb_hcd_platform_shutdown); +int usb_hcd_setup_local_mem(struct usb_hcd *hcd, phys_addr_t phys_addr, + dma_addr_t dma, size_t size) +{ + int err; + void *local_mem; + + hcd->localmem_pool = devm_gen_pool_create(hcd->self.sysdev, 4, + dev_to_node(hcd->self.sysdev), + dev_name(hcd->self.sysdev)); + 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 (!local_mem) + return -ENOMEM; + + /* + * Here we pass a dma_addr_t but the arg type is a phys_addr_t. + * It's not backed by system memory and thus there's no kernel mapping + * for it. + */ + err = gen_pool_add_virt(hcd->localmem_pool, (unsigned long)local_mem, + dma, size, dev_to_node(hcd->self.sysdev)); + if (err < 0) { + dev_err(hcd->self.sysdev, "gen_pool_add_virt failed with %d\n", + err); + return err; + } + + return 0; +} +EXPORT_SYMBOL_GPL(usb_hcd_setup_local_mem); + /*-------------------------------------------------------------------------*/ #if IS_ENABLED(CONFIG_USB_MON) |