USB: drop HCD_LOCAL_MEM flag

With the addition of the local memory allocator, the HCD_LOCAL_MEM
flag can be dropped and the checks against it replaced with a check
for the localmem_pool ptr being initialized.

Signed-off-by: Laurentiu Tudor <laurentiu.tudor@nxp.com>
Tested-by: Fredrik Noring <noring@nocrew.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>

2 files changed, 9 insertions, 14 deletions

diff --git a/drivers/usb/core/buffer.c b/drivers/usb/core/buffer.c
index d2064ad7ad14..1359b78a624e 100644
--- a/drivers/usb/core/buffer.c
+++ b/drivers/usb/core/buffer.c
@@ -68,7 +68,7 @@ int hcd_buffer_create(struct usb_hcd *hcd)
 
 	if (!IS_ENABLED(CONFIG_HAS_DMA) ||
 	    (!is_device_dma_capable(hcd->self.sysdev) &&
-	     !(hcd->driver->flags & HCD_LOCAL_MEM)))
+	     !hcd->localmem_pool))
 		return 0;
 
 	for (i = 0; i < HCD_BUFFER_POOLS; i++) {
@@ -130,8 +130,7 @@ void *hcd_buffer_alloc(
 
 	/* some USB hosts just use PIO */
 	if (!IS_ENABLED(CONFIG_HAS_DMA) ||
-	    (!is_device_dma_capable(bus->sysdev) &&
-	     !(hcd->driver->flags & HCD_LOCAL_MEM))) {
+	    !is_device_dma_capable(bus->sysdev)) {
 		*dma = ~(dma_addr_t) 0;
 		return kmalloc(size, mem_flags);
 	}
@@ -162,8 +161,7 @@ void hcd_buffer_free(
 	}
 
 	if (!IS_ENABLED(CONFIG_HAS_DMA) ||
-	    (!is_device_dma_capable(bus->sysdev) &&
-	     !(hcd->driver->flags & HCD_LOCAL_MEM))) {
+	    !is_device_dma_capable(bus->sysdev)) {
 		kfree(addr);
 		return;
 	}
diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c
index 29b96e5e8621..fe631d18c1ed 100644
--- a/drivers/usb/core/hcd.c
+++ b/drivers/usb/core/hcd.c
@@ -1347,14 +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...
  *
@@ -1364,9 +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".
@@ -1533,7 +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,
@@ -1603,7 +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,