Sergey, can you test whether this fixes your issue?
Sarah Sharp
8<----------------------------------------------------------->8
Commit 9df89d85b407690afa46ddfbccc80bec6869971d "usbcore: set
lpm_capable field for LPM capable root hubs" was created under the
assumption that all USB host controllers should have USB 3.0 Link PM
enabled for all devices under the hosts.
Unfortunately, that's not the case. The xHCI driver relies on knowledge
of the host hardware scheduler to calculate the LPM U1/U2 timeout
values, and it only sets lpm_capable to one for Intel host controllers
(that have the XHCI_LPM_SUPPORT quirk set).
When LPM is enabled for some Fresco Logic hosts, it causes failures with
a AgeStar 3UBT USB 3.0 hard drive dock:
Jan 11 13:59:03 sg-laptop kernel: usb 3-1: new SuperSpeed USB device number 2 using xhci_hcd
Jan 11 13:59:03 sg-laptop kernel: usb 3-1: Set SEL for device-initiated U1 failed.
Jan 11 13:59:08 sg-laptop kernel: usb 3-1: Set SEL for device-initiated U2 failed.
Jan 11 13:59:08 sg-laptop kernel: usb-storage 3-1:1.0: USB Mass Storage device detected
Jan 11 13:59:08 sg-laptop mtp-probe[613]: checking bus 3, device 2: "/sys/devices/pci0000:00/0000:00:1c.3/0000:04:00.0/usb3/3-1"
Jan 11 13:59:08 sg-laptop mtp-probe[613]: bus: 3, device: 2 was not an MTP device
Jan 11 13:59:08 sg-laptop kernel: scsi6 : usb-storage 3-1:1.0
Jan 11 13:59:13 sg-laptop kernel: usb 3-1: Set SEL for device-initiated U1 failed.
Jan 11 13:59:18 sg-laptop kernel: usb 3-1: Set SEL for device-initiated U2 failed.
Jan 11 13:59:18 sg-laptop kernel: usbcore: registered new interface driver usb-storage
Jan 11 13:59:40 sg-laptop kernel: usb 3-1: reset SuperSpeed USB device number 2 using xhci_hcd
Jan 11 13:59:41 sg-laptop kernel: usb 3-1: device descriptor read/8, error -71
Jan 11 13:59:41 sg-laptop kernel: usb 3-1: reset SuperSpeed USB device number 2 using xhci_hcd
Jan 11 13:59:46 sg-laptop kernel: usb 3-1: device descriptor read/8, error -110
Jan 11 13:59:46 sg-laptop kernel: scsi 6:0:0:0: Device offlined - not ready after error recovery
Jan 11 13:59:46 sg-laptop kernel: usb 3-1: USB disconnect, device number 2
lspci for the affected host:
04:00.0 0c03: 1b73:1000 (rev 04) (prog-if 30 [XHCI])
Subsystem: 1043:1039
Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
Latency: 0, Cache Line Size: 64 bytes
Interrupt: pin A routed to IRQ 19
Region 0: Memory at dd200000 (32-bit, non-prefetchable) [size=64K]
Capabilities: [50] Power Management version 3
Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA PME(D0+,D1-,D2-,D3hot+,D3cold-)
Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME-
Capabilities: [68] MSI: Enable- Count=1/1 Maskable- 64bit+
Address: 0000000000000000 Data: 0000
Capabilities: [80] Express (v1) Endpoint, MSI 00
DevCap: MaxPayload 128 bytes, PhantFunc 0, Latency L0s <2us, L1 <32us
ExtTag- AttnBtn- AttnInd- PwrInd- RBE+ FLReset-
DevCtl: Report errors: Correctable- Non-Fatal- Fatal- Unsupported-
RlxdOrd+ ExtTag- PhantFunc- AuxPwr- NoSnoop+
MaxPayload 128 bytes, MaxReadReq 512 bytes
DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr- TransPend-
LnkCap: Port #0, Speed 2.5GT/s, Width x1, ASPM L0s L1, Latency L0 unlimited, L1 unlimited
ClockPM- Surprise- LLActRep- BwNot-
LnkCtl: ASPM Disabled; RCB 64 bytes Disabled- Retrain- CommClk+
ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
LnkSta: Speed 2.5GT/s, Width x1, TrErr- Train- SlotClk+ DLActive- BWMgmt- ABWMgmt-
Kernel driver in use: xhci_hcd
Kernel modules: xhci_hcd
The xHCI driver shouldn't really be mucking with USB core internal
fields, so rip that out. Instead, indicate the xHCI driver doesn't
support Link PM on this host by clearing the U1 and U2 exit latencies in
the roothub SuperSpeed Extended Capabilities BOS descriptor.
This will also disable LPM for external devices that have the U1 and U2
exit latencies set to zero. This was already effectively done with
commit ae8963adb4ad8c5f2a89ca1d99fb7bb721e7599f "usb: Don't enable LPM
if the exit latency is zero." Leave that code in place, in case there
are devices out there that set one exit latency value to zero, but set
the other to a valid value.
Also, change messages about missing Link PM information from warning
level to info level. Only print a warning about the first device that
doesn't support LPM, to avoid log spam. Further, cleanup some
unnecessary line breaks.
Signed-off-by: Sarah Sharp <sarah.a.sharp@xxxxxxxxxxxxxxx>
Reported-by: Sergey Galanov <sergey.e.galanov@xxxxxxxxx>
Cc: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
---
drivers/usb/core/hub.c | 25 ++++++++++++++-----------
drivers/usb/host/xhci-hub.c | 8 +++++---
drivers/usb/host/xhci-pci.c | 6 ------
3 files changed, 19 insertions(+), 20 deletions(-)
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index babba885978d..3345fd771cf6 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -141,24 +141,27 @@ int usb_device_supports_lpm(struct usb_device *udev)
return 0;
}
- /* All USB 3.0 must support LPM, but we need their max exit latency
- * information from the SuperSpeed Extended Capabilities BOS descriptor.
+ /*
+ * According to the USB 3.0 spec, all USB 3.0 devices must support LPM.
+ * However, there are some that don't, and they set the U1/U2 exit
+ * latencies to zero.
*/
if (!udev->bos->ss_cap) {
- dev_warn(&udev->dev, "No LPM exit latency info found. "
- "Power management will be impacted.\n");
+ dev_info(&udev->dev, "No LPM exit latency info found, disabling LPM.\n");
return 0;
}
- /* udev is root hub */
- if (!udev->parent)
- return 1;
+ if (udev->bos->ss_cap->bU1devExitLat == 0 &&
+ udev->bos->ss_cap->bU2DevExitLat == 0) {
+ if (udev->parent)
+ dev_info(&udev->dev, "LPM exit latency is zeroed, disabling LPM.\n");
+ else
+ dev_info(&udev->dev, "We don't know the algorithms for LPM for this host, disabling LPM.\n");
+ return 0;
+ }
- if (udev->parent->lpm_capable)
+ if (!udev->parent || udev->parent->lpm_capable)
return 1;
-
- dev_warn(&udev->dev, "Parent hub missing LPM exit latency info. "
- "Power management will be impacted.\n");
return 0;
}
diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c
index 9992fbfec85f..1ad6bc1951c7 100644
--- a/drivers/usb/host/xhci-hub.c
+++ b/drivers/usb/host/xhci-hub.c
@@ -732,9 +732,11 @@ int xhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
/* Set the U1 and U2 exit latencies. */
memcpy(buf, &usb_bos_descriptor,
USB_DT_BOS_SIZE + USB_DT_USB_SS_CAP_SIZE);
- temp = readl(&xhci->cap_regs->hcs_params3);
- buf[12] = HCS_U1_LATENCY(temp);
- put_unaligned_le16(HCS_U2_LATENCY(temp), &buf[13]);
+ if ((xhci->quirks & XHCI_LPM_SUPPORT)) {
+ temp = readl(&xhci->cap_regs->hcs_params3);
+ buf[12] = HCS_U1_LATENCY(temp);
+ put_unaligned_le16(HCS_U2_LATENCY(temp), &buf[13]);
+ }
/* Indicate whether the host has LTM support. */
temp = readl(&xhci->cap_regs->hcc_params);
diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c
index 3c898c12a06b..e42c318a4404 100644
--- a/drivers/usb/host/xhci-pci.c
+++ b/drivers/usb/host/xhci-pci.c
@@ -217,12 +217,6 @@ static int xhci_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
goto put_usb3_hcd;
/* Roothub already marked as USB 3.0 speed */
- /* We know the LPM timeout algorithms for this host, let the USB core
- * enable and disable LPM for devices under the USB 3.0 roothub.
- */
- if (xhci->quirks & XHCI_LPM_SUPPORT)
- hcd_to_bus(xhci->shared_hcd)->root_hub->lpm_capable = 1;
-
return 0;
put_usb3_hcd:
--
1.8.5.2
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