lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

USB: make urb scatter-gather support more generic

Browse Source 
The WHCI HCD will also support urbs with scatter-gather lists.  Add a
usb_bus field to indicated how many sg list elements are supported by
the HCD.  Use this to decide whether to pass the scatter-list to the HCD
or not.

Make the usb-storage driver use this new field.

Signed-off-by: David Vrabel <david.vrabel@csr.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: Matthew Dharm <mdharm-usb@one-eyed-alien.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
David Vrabel
2009-08-24 14:44:30 +01:00
committed by Greg Kroah-Hartman
parent 09ce497e79
commit 4c1bd3d7a7
4 changed files with 14 additions and 7 deletions
Download Patch File Download Diff File Expand all files Collapse all files

10
drivers/usb/storage/usb.c
View File

@@ -843,6 +843,15 @@ static int usb_stor_scan_thread(void * __us)
complete_and_exit(&us->scanning_done, 0);
}
static unsigned int usb_stor_sg_tablesize(struct usb_interface *intf)
{
struct usb_device *usb_dev = interface_to_usbdev(intf);
if (usb_dev->bus->sg_tablesize) {
return usb_dev->bus->sg_tablesize;
}
return SG_ALL;
}
/* First part of general USB mass-storage probing */
int usb_stor_probe1(struct us_data **pus,
@@ -871,6 +880,7 @@ int usb_stor_probe1(struct us_data **pus,
* Allow 16-byte CDBs and thus > 2TB
*/
host->max_cmd_len = 16;
host->sg_tablesize = usb_stor_sg_tablesize(intf);
*pus = us = host_to_us(host);
memset(us, 0, sizeof(struct us_data));
mutex_init(&(us->dev_mutex));