usb: add a hcd_uses_dma helper

The USB buffer allocation code is the only place in the usb core (and in
fact the whole kernel) that uses is_device_dma_capable, while the URB
mapping code uses the uses_dma flag in struct usb_bus.  Switch the buffer
allocation to use the uses_dma flag used by the rest of the USB code,
and create a helper in hcd.h that checks this flag as well as the
CONFIG_HAS_DMA to simplify the caller a bit.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20190811080520.21712-3-hch@lst.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/core/buffer.c b/drivers/usb/core/buffer.c
index 1a5b3dcae930052a171a589583ad18188f7dceb5..6cf22c27f2d24e3eb74f631cd2adb07e8c685ce6 100644 (file)
--- a/drivers/usb/core/buffer.c
+++ b/drivers/usb/core/buffer.c
@@ -66,9 +66,7 @@ int hcd_buffer_create(struct usb_hcd *hcd)
        char            name[16];
        int             i, size;
 
-       if (hcd->localmem_pool ||
-           !IS_ENABLED(CONFIG_HAS_DMA) ||
-           !is_device_dma_capable(hcd->self.sysdev))
+       if (hcd->localmem_pool || !hcd_uses_dma(hcd))
                return 0;
 
        for (i = 0; i < HCD_BUFFER_POOLS; i++) {
@@ -129,8 +127,7 @@ void *hcd_buffer_alloc(
                return gen_pool_dma_alloc(hcd->localmem_pool, size, dma);
 
        /* some USB hosts just use PIO */
-       if (!IS_ENABLED(CONFIG_HAS_DMA) ||
-           !is_device_dma_capable(bus->sysdev)) {
+       if (!hcd_uses_dma(hcd)) {
                *dma = ~(dma_addr_t) 0;
                return kmalloc(size, mem_flags);
        }
@@ -160,8 +157,7 @@ void hcd_buffer_free(
                return;
        }
 
-       if (!IS_ENABLED(CONFIG_HAS_DMA) ||
-           !is_device_dma_capable(bus->sysdev)) {
+       if (!hcd_uses_dma(hcd)) {
                kfree(addr);
                return;
        }

diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c
index 2ccbc2f83570141c7dc6c3b3bfe882ca5286eac3..8592c0344fe81f1458cacf1eaf55bfa516049121 100644 (file)
--- a/drivers/usb/core/hcd.c
+++ b/drivers/usb/core/hcd.c
@@ -1412,7 +1412,7 @@ int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
        if (usb_endpoint_xfer_control(&urb->ep->desc)) {
                if (hcd->self.uses_pio_for_control)
                        return ret;
-               if (IS_ENABLED(CONFIG_HAS_DMA) && hcd->self.uses_dma) {
+               if (hcd_uses_dma(hcd)) {
                        if (is_vmalloc_addr(urb->setup_packet)) {
                                WARN_ONCE(1, "setup packet is not dma capable\n");
                                return -EAGAIN;
@@ -1446,7 +1446,7 @@ int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
        dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
        if (urb->transfer_buffer_length != 0
            && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) {
-               if (IS_ENABLED(CONFIG_HAS_DMA) && hcd->self.uses_dma) {
+               if (hcd_uses_dma(hcd)) {
                        if (urb->num_sgs) {
                                int n;
 

diff --git a/drivers/usb/dwc2/hcd.c b/drivers/usb/dwc2/hcd.c
index ee144ff8af5b1195f08ce0466d0586231f3d0dd3..111787a137eead0bd65e554bc2a9705ad39dbcc9 100644 (file)
--- a/drivers/usb/dwc2/hcd.c
+++ b/drivers/usb/dwc2/hcd.c
@@ -4608,7 +4608,7 @@ static int _dwc2_hcd_urb_enqueue(struct usb_hcd *hcd, struct urb *urb,
 
        buf = urb->transfer_buffer;
 
-       if (hcd->self.uses_dma) {
+       if (hcd_uses_dma(hcd)) {
                if (!buf && (urb->transfer_dma & 3)) {
                        dev_err(hsotg->dev,
                                "%s: unaligned transfer with no transfer_buffer",

diff --git a/include/linux/usb.h b/include/linux/usb.h
index 83d35d993e8c91cda28eb4f6f0ff222750a4a1db..e87826e23d593026f4d2fb2432f418f716585b67 100644 (file)
--- a/include/linux/usb.h
+++ b/include/linux/usb.h
@@ -1457,7 +1457,7 @@ typedef void (*usb_complete_t)(struct urb *);
  * field rather than determining a dma address themselves.
  *
  * Note that transfer_buffer must still be set if the controller
- * does not support DMA (as indicated by bus.uses_dma) and when talking
+ * does not support DMA (as indicated by hcd_uses_dma()) and when talking
  * to root hub. If you have to trasfer between highmem zone and the device
  * on such controller, create a bounce buffer or bail out with an error.
  * If transfer_buffer cannot be set (is in highmem) and the controller is DMA

diff --git a/include/linux/usb/hcd.h b/include/linux/usb/hcd.h
index bab27ccc8ff564eb70d364746e1fc317c0fd3fb2..a20e7815d814cb1fd6f84c91730d8584f8381fe4 100644 (file)
--- a/include/linux/usb/hcd.h
+++ b/include/linux/usb/hcd.h
@@ -422,6 +422,9 @@ static inline bool hcd_periodic_completion_in_progress(struct usb_hcd *hcd,
        return hcd->high_prio_bh.completing_ep == ep;
 }
 
+#define hcd_uses_dma(hcd) \
+       (IS_ENABLED(CONFIG_HAS_DMA) && (hcd)->self.uses_dma)
+
 extern int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb);
 extern int usb_hcd_check_unlink_urb(struct usb_hcd *hcd, struct urb *urb,
                int status);