From 424140d31ba1c613e7a087caf87723d0273f4dae Mon Sep 17 00:00:00 2001 From: Mathias Nyman Date: Thu, 12 May 2022 01:04:48 +0300 Subject: xhci: prevent U2 link power state if Intel tier policy prevented U1 Don't enable U1 or U2 Link powermanagenet (LPM) states for USB3 devices connected to tier 2 or further hubs. For unknown reasons we previously only prevented U1. Be consistent, and prevent both U1/U2 states if tier policy doesn't allow LPM. Also check the tier policy a bit earlier, and return if U1/U2 is not allowed. This avoids unnecessary xhci MEL commands. Signed-off-by: Mathias Nyman Link: https://lore.kernel.org/r/20220511220450.85367-8-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/xhci.c | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-) (limited to 'drivers/usb') diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c index e66a031de5a3..d957eac59ab3 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -4888,9 +4888,6 @@ static int xhci_check_intel_tier_policy(struct usb_device *udev, struct usb_device *parent; unsigned int num_hubs; - if (state == USB3_LPM_U2) - return 0; - /* 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) @@ -4899,7 +4896,7 @@ static int xhci_check_intel_tier_policy(struct usb_device *udev, if (num_hubs < 2) return 0; - dev_dbg(&udev->dev, "Disabling U1 link state for device" + 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"); @@ -4940,9 +4937,6 @@ static u16 xhci_calculate_lpm_timeout(struct usb_hcd *hcd, return timeout; } - if (xhci_check_tier_policy(xhci, udev, state) < 0) - return timeout; - /* Gather some information about the currently installed configuration * and alternate interface settings. */ @@ -5049,6 +5043,9 @@ static int xhci_enable_usb3_lpm_timeout(struct usb_hcd *hcd, !xhci->devs[udev->slot_id]) return USB3_LPM_DISABLED; + if (xhci_check_tier_policy(xhci, udev, state) < 0) + return USB3_LPM_DISABLED; + hub_encoded_timeout = xhci_calculate_lpm_timeout(hcd, udev, state); mel = calculate_max_exit_latency(udev, state, hub_encoded_timeout); if (mel < 0) { -- cgit v1.2.3