Patchwork [U-Boot,v4,1/3] USB: make usb_kbd obey USB DMA alignment requirements

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Submitter Allen Martin
Date Oct. 24, 2012, 6:32 p.m.
Message ID <1351103526-10797-1-git-send-email-amartin@nvidia.com>
Download mbox | patch
Permalink /patch/193904/
State Awaiting Upstream
Delegated to: Marek Vasut
Headers show

Comments

Allen Martin - Oct. 24, 2012, 6:32 p.m.
Change usb_kbd driver to obey alignment requirements for USB DMA on
the buffer used for data transfer.  This is necessary for
architectures that enable dcache and enable USB DMA.

Signed-off-by: Allen Martin <amartin@nvidia.com>
---
v4: dynamically allocate xfer buffer, add alignment and roundup to buffer
    instead of entire pdata struct
v3: add comment about alignemnt requirement
v2: use memalign instead of __align()
---
 common/usb_kbd.c |    5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)
Stephen Warren - Oct. 24, 2012, 6:54 p.m.
On 10/24/2012 12:32 PM, Allen Martin wrote:
> Change usb_kbd driver to obey alignment requirements for USB DMA on
> the buffer used for data transfer.  This is necessary for
> architectures that enable dcache and enable USB DMA.

Tested-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>

Patch

diff --git a/common/usb_kbd.c b/common/usb_kbd.c
index 19f01db..24467ce 100644
--- a/common/usb_kbd.c
+++ b/common/usb_kbd.c
@@ -112,7 +112,7 @@  struct usb_kbd_pdata {
 	uint32_t	usb_out_pointer;
 	uint8_t		usb_kbd_buffer[USB_KBD_BUFFER_LEN];
 
-	uint8_t		new[8];
+	uint8_t		*new;
 	uint8_t		old[8];
 
 	uint8_t		flags;
@@ -435,6 +435,9 @@  static int usb_kbd_probe(struct usb_device *dev, unsigned int ifnum)
 	/* Clear private data */
 	memset(data, 0, sizeof(struct usb_kbd_pdata));
 
+	/* allocate input buffer aligned and sized to USB DMA alignment */
+	data->new = memalign(USB_DMA_MINALIGN, roundup(8, USB_DMA_MINALIGN));
+
 	/* Insert private data into USB device structure */
 	dev->privptr = data;