diff options
| author | Jiahau Chang <jiahau@gmail.com> | 2017-07-20 14:48:27 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-07-20 14:40:35 +0200 |
| commit | 9da5a1092b13468839b1a864b126cacfb72ad016 (patch) | |
| tree | 150639fa1c21c53e0d6988bd3b2f5d1a10e2e904 /drivers/usb/host/xhci.c | |
| parent | 4b895868bb2da60a386a17cde3bf9ecbc70c79f4 (diff) | |
xhci: Bad Ethernet performance plugged in ASM1042A host
When USB Ethernet is plugged in ASMEDIA ASM1042A xHCI host, bad
performance was manifesting in Web browser use (like download
large file such as ISO image). It is known limitation of
ASM1042A that is not compatible with driver scheduling,
As a workaround we can modify flow control handling of ASM1042A.
The register we modify is changes the behavior
[use quirk bit 28, usleep_range 40-60us, empty non-pci function -Mathias]
Cc: <stable@vger.kernel.org>
Signed-off-by: Jiahau Chang <Lars_chang@asmedia.com.tw>
Signed-off-by: Ian Pilcher <arequipeno@gmail.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb/host/xhci.c')
| -rw-r--r-- | drivers/usb/host/xhci.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c index 56f85df013db..51326425f9cc 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -198,6 +198,9 @@ int xhci_reset(struct xhci_hcd *xhci) if (ret) return ret; + if (xhci->quirks & XHCI_ASMEDIA_MODIFY_FLOWCONTROL) + usb_asmedia_modifyflowcontrol(to_pci_dev(xhci_to_hcd(xhci)->self.controller)); + xhci_dbg_trace(xhci, trace_xhci_dbg_init, "Wait for controller to be ready for doorbell rings"); /* @@ -1085,6 +1088,9 @@ int xhci_resume(struct xhci_hcd *xhci, bool hibernated) if ((xhci->quirks & XHCI_COMP_MODE_QUIRK) && !comp_timer_running) compliance_mode_recovery_timer_init(xhci); + if (xhci->quirks & XHCI_ASMEDIA_MODIFY_FLOWCONTROL) + usb_asmedia_modifyflowcontrol(to_pci_dev(hcd->self.controller)); + /* Re-enable port polling. */ xhci_dbg(xhci, "%s: starting port polling.\n", __func__); set_bit(HCD_FLAG_POLL_RH, &xhci->shared_hcd->flags); |