USB: EHCI: work around bug in the Philips ISP1562 controller

This patch (as1556) works around a bug in the Philips ISP1562 EHCI
controller.  Although the controller claims to support frame-list
lengths smaller than the default of 1024 for its periodic schedule, in
fact smaller values don't work.  A new quirk flag is added to indicate
when the bug is present, and if it is then the schedule size is left
at the default value.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Alan Stern 2012-05-14 13:48:16 -04:00 committed by Greg Kroah-Hartman
parent 65b8e5cbdd
commit 1996e6c572
3 changed files with 9 additions and 1 deletions

View File

@ -639,7 +639,7 @@ static int ehci_init(struct usb_hcd *hcd)
INIT_LIST_HEAD(&ehci->cached_itd_list);
INIT_LIST_HEAD(&ehci->cached_sitd_list);
if (HCC_PGM_FRAMELISTLEN(hcc_params)) {
if (HCC_PGM_FRAMELISTLEN(hcc_params) && !ehci->sched_size_bug) {
/* periodic schedule size can be smaller than default */
switch (EHCI_TUNE_FLS) {
case 0: ehci->periodic_size = 1024; break;

View File

@ -97,6 +97,13 @@ static int ehci_pci_setup(struct usb_hcd *hcd)
break;
}
break;
case PCI_VENDOR_ID_PHILIPS:
/*
* Philips controllers set HCC_PGM_FRAMELISTLEN, but
* they don't implement schedule sizes shorter than 1024.
*/
ehci->sched_size_bug = 1;
}
/* cache this readonly data; minimize chip reads */

View File

@ -149,6 +149,7 @@ struct ehci_hcd { /* one per controller */
unsigned use_dummy_qh:1; /* AMD Frame List table quirk*/
unsigned has_synopsys_hc_bug:1; /* Synopsys HC */
unsigned frame_index_bug:1; /* MosChip (AKA NetMos) */
unsigned sched_size_bug:1; /* Philips */
/* required for usb32 quirk */
#define OHCI_CTRL_HCFS (3 << 6)