Add U1/U2 feature support of xHCI for zhaoxin.
Since both Intel and Zhaoxin need to check the tier where the device is
located to determine whether to enabled U1/U2, remove the previous Intel
U1/U2 tier policy and add common policy in xhci_check_tier_policy.
If vendor has specific U1/U2 enable policy,quirks can be add to declare.
Suggested-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Weitao Wang <WeitaoWang-oc@xxxxxxxxxxx>
---
v1->v2
- Modify the description.
- Adjust U1/U2 tier enable policy.
drivers/usb/host/xhci.c | 43 +++++++++++++++++------------------------
1 file changed, 18 insertions(+), 25 deletions(-)
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 31d6ace9cace..b81a69126188 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -4802,7 +4802,7 @@ static u16 xhci_calculate_u1_timeout(struct xhci_hcd *xhci,
}
}
- if (xhci->quirks & XHCI_INTEL_HOST)
+ if (xhci->quirks & (XHCI_INTEL_HOST | XHCI_ZHAOXIN_HOST))
timeout_ns = xhci_calculate_intel_u1_timeout(udev, desc);
else
timeout_ns = udev->u1_params.sel;
@@ -4866,7 +4866,7 @@ static u16 xhci_calculate_u2_timeout(struct xhci_hcd *xhci,
}
}
- if (xhci->quirks & XHCI_INTEL_HOST)
+ if (xhci->quirks & (XHCI_INTEL_HOST | XHCI_ZHAOXIN_HOST))
timeout_ns = xhci_calculate_intel_u2_timeout(udev, desc);
else
timeout_ns = udev->u2_params.sel;
@@ -4938,37 +4938,30 @@ static int xhci_update_timeout_for_interface(struct xhci_hcd *xhci,
return 0;
}
-static int xhci_check_intel_tier_policy(struct usb_device *udev,
+static int xhci_check_tier_policy(struct xhci_hcd *xhci,
+ struct usb_device *udev,
enum usb3_link_state state)
{
- struct usb_device *parent;
- unsigned int num_hubs;
+ struct usb_device *parent = udev->parent;
+ int tier = 1; /* roothub is tier1 */
- /* Don't enable U1 if the device is on a 2nd tier hub or lower. */
- for (parent = udev->parent, num_hubs = 0; parent->parent;
- parent = parent->parent)
- num_hubs++;
+ while (parent) {
+ parent = parent->parent;
+ tier++;
+ }
- if (num_hubs < 2)
- return 0;
+ if (xhci->quirks & XHCI_INTEL_HOST && tier > 3)
+ goto fail;
+ if (xhci->quirks & XHCI_ZHAOXIN_HOST && tier > 2)
+ goto fail;
- dev_dbg(&udev->dev, "Disabling U1/U2 link state for device"
- " below second-tier hub.\n");
- dev_dbg(&udev->dev, "Plug device into first-tier hub "
- "to decrease power consumption.\n");
+ return 0;
+fail:
+ dev_dbg(&udev->dev, "Tier policy prevents U1/U2 LPM states for devices at tier %d\n",
+ tier);
return -E2BIG;
}
-static int xhci_check_tier_policy(struct xhci_hcd *xhci,
- struct usb_device *udev,
- enum usb3_link_state state)
-{
- if (xhci->quirks & XHCI_INTEL_HOST)
- return xhci_check_intel_tier_policy(udev, state);
- else
- return 0;
-}
-
/* Returns the U1 or U2 timeout that should be enabled.
* If the tier check or timeout setting functions return with a non-zero exit
* code, that means the timeout value has been finalized and we shouldn't look
--
2.32.0
