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@xxxxxxxxxxxxxxxxxxx>
---
drivers/usb/host/ehci-hcd.c | 2 +-
drivers/usb/host/ehci-pci.c | 7 +++++++
drivers/usb/host/ehci.h | 1 +
3 files changed, 9 insertions(+), 1 deletion(-)
Index: usb-3.4/drivers/usb/host/ehci.h
===================================================================
--- usb-3.4.orig/drivers/usb/host/ehci.h
+++ usb-3.4/drivers/usb/host/ehci.h
@@ -149,6 +149,7 @@ struct ehci_hcd { /* one per controlle
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)
Index: usb-3.4/drivers/usb/host/ehci-hcd.c
===================================================================
--- usb-3.4.orig/drivers/usb/host/ehci-hcd.c
+++ usb-3.4/drivers/usb/host/ehci-hcd.c
@@ -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;
Index: usb-3.4/drivers/usb/host/ehci-pci.c
===================================================================
--- usb-3.4.orig/drivers/usb/host/ehci-pci.c
+++ usb-3.4/drivers/usb/host/ehci-pci.c
@@ -97,6 +97,13 @@ static int ehci_pci_setup(struct usb_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 */
--
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