xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

USB: remove uses of URB_NO_SETUP_DMA_MAP

Browse Source 
This patch (as1350) removes all usages of coherent buffers for USB
control-request setup-packet buffers.  There's no good reason to
reserve coherent memory for these things; control requests are hardly
ever used in large quantity (the major exception is firmware
transfers, and they aren't time-critical).  Furthermore, only seven
drivers used it.  We might as well always use streaming DMA mappings
for setup-packet buffers, and remove some extra complexity from
usbcore.

The DMA-mapping portion of hcd.c is currently in flux.  A separate
patch will be submitted to remove support for URB_NO_SETUP_DMA_MAP
after everything else settles down.  The removal should go smoothly,
as by then nobody will be using it.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Alan Stern
2010-03-05 15:10:17 -05:00
committed by Greg Kroah-Hartman
parent 749da5f82f
commit 0ede76fcec
13 changed files with 27 additions and 75 deletions
Download Patch File Download Diff File Expand all files Collapse all files

9
drivers/usb/misc/usbtest.c
View File

@@ -977,15 +977,13 @@ test_ctrl_queue (struct usbtest_dev *dev, struct usbtest_param *param)
if (!u)
goto cleanup;
reqp = usb_buffer_alloc (udev, sizeof *reqp, GFP_KERNEL,
&u->setup_dma);
reqp = kmalloc(sizeof *reqp, GFP_KERNEL);
if (!reqp)
goto cleanup;
reqp->setup = req;
reqp->number = i % NUM_SUBCASES;
reqp->expected = expected;
u->setup_packet = (char *) &reqp->setup;
u->transfer_flags |= URB_NO_SETUP_DMA_MAP;
u->context = &context;
u->complete = ctrl_complete;
@@ -1017,10 +1015,7 @@ cleanup:
if (!urb [i])
continue;
urb [i]->dev = udev;
if (urb [i]->setup_packet)
usb_buffer_free (udev, sizeof (struct usb_ctrlrequest),
urb [i]->setup_packet,
urb [i]->setup_dma);
kfree(urb[i]->setup_packet);
simple_free_urb (urb [i]);
}
kfree (urb);