1 files changed, 20 insertions, 28 deletions

diff --git a/drivers/usb/chipidea/host.c b/drivers/usb/chipidea/host.c
index f40bd322f3c8..bec90385067b 100644
--- a/drivers/usb/chipidea/host.c
+++ b/drivers/usb/chipidea/host.c
@@ -31,8 +31,7 @@ struct ehci_ci_priv {
 };
 
 struct ci_hdrc_dma_aligned_buffer {
-	void *kmalloc_ptr;
-	void *old_xfer_buffer;
+	void *original_buffer;
 	u8 data[];
 };
 
@@ -418,59 +417,52 @@ static int ci_ehci_bus_suspend(struct usb_hcd *hcd)
 	return 0;
 }
 
-static void ci_hdrc_free_dma_aligned_buffer(struct urb *urb)
+static void ci_hdrc_free_dma_aligned_buffer(struct urb *urb, bool copy_back)
 {
 	struct ci_hdrc_dma_aligned_buffer *temp;
-	size_t length;
 
 	if (!(urb->transfer_flags & URB_ALIGNED_TEMP_BUFFER))
 		return;
+	urb->transfer_flags &= ~URB_ALIGNED_TEMP_BUFFER;
 
 	temp = container_of(urb->transfer_buffer,
 			    struct ci_hdrc_dma_aligned_buffer, data);
+	urb->transfer_buffer = temp->original_buffer;
+
+	if (copy_back && usb_urb_dir_in(urb)) {
+		size_t length;
 
-	if (usb_urb_dir_in(urb)) {
 		if (usb_pipeisoc(urb->pipe))
 			length = urb->transfer_buffer_length;
 		else
 			length = urb->actual_length;
 
-		memcpy(temp->old_xfer_buffer, temp->data, length);
+		memcpy(temp->original_buffer, temp->data, length);
 	}
-	urb->transfer_buffer = temp->old_xfer_buffer;
-	kfree(temp->kmalloc_ptr);
 
-	urb->transfer_flags &= ~URB_ALIGNED_TEMP_BUFFER;
+	kfree(temp);
 }
 
 static int ci_hdrc_alloc_dma_aligned_buffer(struct urb *urb, gfp_t mem_flags)
 {
-	struct ci_hdrc_dma_aligned_buffer *temp, *kmalloc_ptr;
-	const unsigned int ci_hdrc_usb_dma_align = 32;
-	size_t kmalloc_size;
+	struct ci_hdrc_dma_aligned_buffer *temp;
 
-	if (urb->num_sgs || urb->sg || urb->transfer_buffer_length == 0 ||
-	    !((uintptr_t)urb->transfer_buffer & (ci_hdrc_usb_dma_align - 1)))
+	if (urb->num_sgs || urb->sg || urb->transfer_buffer_length == 0)
+		return 0;
+	if (IS_ALIGNED((uintptr_t)urb->transfer_buffer, 4)
+	    && IS_ALIGNED(urb->transfer_buffer_length, 4))
 		return 0;
 
-	/* Allocate a buffer with enough padding for alignment */
-	kmalloc_size = urb->transfer_buffer_length +
-		       sizeof(struct ci_hdrc_dma_aligned_buffer) +
-		       ci_hdrc_usb_dma_align - 1;
-
-	kmalloc_ptr = kmalloc(kmalloc_size, mem_flags);
-	if (!kmalloc_ptr)
+	temp = kmalloc(sizeof(*temp) + ALIGN(urb->transfer_buffer_length, 4), mem_flags);
+	if (!temp)
 		return -ENOMEM;
 
-	/* Position our struct dma_aligned_buffer such that data is aligned */
-	temp = PTR_ALIGN(kmalloc_ptr + 1, ci_hdrc_usb_dma_align) - 1;
-	temp->kmalloc_ptr = kmalloc_ptr;
-	temp->old_xfer_buffer = urb->transfer_buffer;
 	if (usb_urb_dir_out(urb))
 		memcpy(temp->data, urb->transfer_buffer,
 		       urb->transfer_buffer_length);
-	urb->transfer_buffer = temp->data;
 
+	temp->original_buffer = urb->transfer_buffer;
+	urb->transfer_buffer = temp->data;
 	urb->transfer_flags |= URB_ALIGNED_TEMP_BUFFER;
 
 	return 0;
@@ -487,7 +479,7 @@ static int ci_hdrc_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
 
 	ret = usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
 	if (ret)
-		ci_hdrc_free_dma_aligned_buffer(urb);
+		ci_hdrc_free_dma_aligned_buffer(urb, false);
 
 	return ret;
 }
@@ -495,7 +487,7 @@ static int ci_hdrc_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
 static void ci_hdrc_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
 {
 	usb_hcd_unmap_urb_for_dma(hcd, urb);
-	ci_hdrc_free_dma_aligned_buffer(urb);
+	ci_hdrc_free_dma_aligned_buffer(urb, true);
 }
 
 static int ci_ehci_bus_resume(struct usb_hcd *hcd)