From: Stanislaw Gruszka <stf_xl@xxxxx>
On some systems rt2800usb and mt7601u devices are unable to operate since
commit f8f80be501aa ("xhci: Use soft retry to recover faster from
transaction errors")
Seems that some xHCI controllers can not perform Soft Retry correctly,
affecting those devices.
To avoid the problem add xhci->quirks flag that restore pre soft retry
xhci behaviour for affected xHCI controllers. Currently those are
AMD_PROMONTORYA_4 and AMD_PROMONTORYA_2, since it was confirmed
by the users: on those xHCI hosts issue happen and is gone after
disabling Soft Retry.
[minor commit message rewording for checkpatch -Mathias]
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202541
Fixes: f8f80be501aa ("xhci: Use soft retry to recover faster from transaction errors")
Cc: <stable@xxxxxxxxxxxxxxx> # 4.20+
Reported-by: Bernhard <bernhard.gebetsberger@xxxxxx>
Tested-by: Bernhard <bernhard.gebetsberger@xxxxxx>
Signed-off-by: Stanislaw Gruszka <stf_xl@xxxxx>
Signed-off-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>
---
drivers/usb/host/xhci-pci.c | 5 +++++
drivers/usb/host/xhci-ring.c | 3 ++-
drivers/usb/host/xhci.h | 1 +
3 files changed, 8 insertions(+), 1 deletion(-)
diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c
index 84da8406d5b4..1f989a49c8c6 100644
--- a/drivers/usb/host/xhci-pci.c
+++ b/drivers/usb/host/xhci-pci.c
@@ -295,6 +295,11 @@ static void xhci_pci_quirks(struct device *dev, struct xhci_hcd *xhci)
pdev->device == 0x9026)
xhci->quirks |= XHCI_RESET_PLL_ON_DISCONNECT;
+ if (pdev->vendor == PCI_VENDOR_ID_AMD &&
+ (pdev->device == PCI_DEVICE_ID_AMD_PROMONTORYA_2 ||
+ pdev->device == PCI_DEVICE_ID_AMD_PROMONTORYA_4))
+ xhci->quirks |= XHCI_NO_SOFT_RETRY;
+
if (xhci->quirks & XHCI_RESET_ON_RESUME)
xhci_dbg_trace(xhci, trace_xhci_dbg_quirks,
"QUIRK: Resetting on resume");
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index 5e548a1c93ab..ce38076901e2 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -2484,7 +2484,8 @@ static int process_bulk_intr_td(struct xhci_hcd *xhci, struct xhci_td *td,
remaining = 0;
break;
case COMP_USB_TRANSACTION_ERROR:
- if ((ep_ring->err_count++ > MAX_SOFT_RETRY) ||
+ if (xhci->quirks & XHCI_NO_SOFT_RETRY ||
+ (ep_ring->err_count++ > MAX_SOFT_RETRY) ||
le32_to_cpu(slot_ctx->tt_info) & TT_SLOT)
break;
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index d41de5dc0452..ca822ad3b65b 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1891,6 +1891,7 @@ struct xhci_hcd {
#define XHCI_SKIP_PHY_INIT BIT_ULL(37)
#define XHCI_DISABLE_SPARSE BIT_ULL(38)
#define XHCI_SG_TRB_CACHE_SIZE_QUIRK BIT_ULL(39)
+#define XHCI_NO_SOFT_RETRY BIT_ULL(40)
unsigned int num_active_eps;
unsigned int limit_active_eps;
--
2.25.1
