+++ /dev/null
-From a44147a09baf8c46cc0b02332df3a4656e0659d5 Mon Sep 17 00:00:00 2001
-From: Arne Fitzenreiter <arne_f@ipfire.org>
-Date: Mon, 10 Dec 2018 13:12:00 +0100
-Subject: [PATCH] Revert "usb: dwc2: Fix DMA alignment to start at allocated
- boundary"
-
-This reverts commit 68fc92a0f3913d539d1ac68a861f895e34099e46.
----
- drivers/usb/dwc2/hcd.c | 44 +++++++++++++++++++++-----------------------
- 1 file changed, 21 insertions(+), 23 deletions(-)
-
-diff --git a/drivers/usb/dwc2/hcd.c b/drivers/usb/dwc2/hcd.c
-index fa20ec4..4b81d08 100644
---- a/drivers/usb/dwc2/hcd.c
-+++ b/drivers/usb/dwc2/hcd.c
-@@ -2644,29 +2644,34 @@ static int dwc2_alloc_split_dma_aligned_buf(struct dwc2_hsotg *hsotg,
-
- #define DWC2_USB_DMA_ALIGN 4
-
-+struct dma_aligned_buffer {
-+ void *kmalloc_ptr;
-+ void *old_xfer_buffer;
-+ u8 data[0];
-+};
-+
- static void dwc2_free_dma_aligned_buffer(struct urb *urb)
- {
-- void *stored_xfer_buffer;
-+ struct dma_aligned_buffer *temp;
-
- if (!(urb->transfer_flags & URB_ALIGNED_TEMP_BUFFER))
- return;
-
-- /* Restore urb->transfer_buffer from the end of the allocated area */
-- memcpy(&stored_xfer_buffer, urb->transfer_buffer +
-- urb->transfer_buffer_length, sizeof(urb->transfer_buffer));
-+ temp = container_of(urb->transfer_buffer,
-+ struct dma_aligned_buffer, data);
-
- if (usb_urb_dir_in(urb))
-- memcpy(stored_xfer_buffer, urb->transfer_buffer,
-+ memcpy(temp->old_xfer_buffer, temp->data,
- urb->transfer_buffer_length);
-- kfree(urb->transfer_buffer);
-- urb->transfer_buffer = stored_xfer_buffer;
-+ urb->transfer_buffer = temp->old_xfer_buffer;
-+ kfree(temp->kmalloc_ptr);
-
- urb->transfer_flags &= ~URB_ALIGNED_TEMP_BUFFER;
- }
-
- static int dwc2_alloc_dma_aligned_buffer(struct urb *urb, gfp_t mem_flags)
- {
-- void *kmalloc_ptr;
-+ struct dma_aligned_buffer *temp, *kmalloc_ptr;
- size_t kmalloc_size;
-
- if (urb->num_sgs || urb->sg ||
-@@ -2674,29 +2679,22 @@ static int dwc2_alloc_dma_aligned_buffer(struct urb *urb, gfp_t mem_flags)
- !((uintptr_t)urb->transfer_buffer & (DWC2_USB_DMA_ALIGN - 1)))
- return 0;
-
-- /*
-- * Allocate a buffer with enough padding for original transfer_buffer
-- * pointer. This allocation is guaranteed to be aligned properly for
-- * DMA
-- */
-+ /* Allocate a buffer with enough padding for alignment */
- kmalloc_size = urb->transfer_buffer_length +
-- sizeof(urb->transfer_buffer);
-+ sizeof(struct dma_aligned_buffer) + DWC2_USB_DMA_ALIGN - 1;
-
- kmalloc_ptr = kmalloc(kmalloc_size, mem_flags);
- if (!kmalloc_ptr)
- return -ENOMEM;
-
-- /*
-- * Position value of original urb->transfer_buffer pointer to the end
-- * of allocation for later referencing
-- */
-- memcpy(kmalloc_ptr + urb->transfer_buffer_length,
-- &urb->transfer_buffer, sizeof(urb->transfer_buffer));
--
-+ /* Position our struct dma_aligned_buffer such that data is aligned */
-+ temp = PTR_ALIGN(kmalloc_ptr + 1, DWC2_USB_DMA_ALIGN) - 1;
-+ temp->kmalloc_ptr = kmalloc_ptr;
-+ temp->old_xfer_buffer = urb->transfer_buffer;
- if (usb_urb_dir_out(urb))
-- memcpy(kmalloc_ptr, urb->transfer_buffer,
-+ memcpy(temp->data, urb->transfer_buffer,
- urb->transfer_buffer_length);
-- urb->transfer_buffer = kmalloc_ptr;
-+ urb->transfer_buffer = temp->data;
-
- urb->transfer_flags |= URB_ALIGNED_TEMP_BUFFER;
-
---
-2.7.4
-