Add LPM u1/u2 feature support for xHCI of zhaoxin

The patch is scheduled to be submitted to the kernel mainline in 2021.

Signed-off-by: LeoLiu-oc LeoLiu-oc@zhaoxin.com --- drivers/usb/host/xhci-pci.c | 4 ++++ drivers/usb/host/xhci.c | 34 ++++++++++++++++++++++++++++++++-- drivers/usb/host/xhci.h | 1 + 3 files changed, 37 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c index 6b828d79a6d8..e1b2dec099f2 100644 --- a/drivers/usb/host/xhci-pci.c +++ b/drivers/usb/host/xhci-pci.c @@ -228,6 +228,10 @@ static void xhci_pci_quirks(struct device *dev, struct xhci_hcd *xhci) } if (pdev->vendor == PCI_VENDOR_ID_VIA) xhci->quirks |= XHCI_RESET_ON_RESUME; + if (pdev->vendor == PCI_VENDOR_ID_ZHAOXIN) { + xhci->quirks |= XHCI_LPM_SUPPORT; + xhci->quirks |= XHCI_ZHAOXIN_HOST; + }

/* See https://bugzilla.kernel.org/show_bug.cgi?id=79511 */ if (pdev->vendor == PCI_VENDOR_ID_VIA && diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c index af659b15258e..fce053a27ade 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -4569,7 +4569,7 @@ static u16 xhci_calculate_u1_timeout(struct xhci_hcd *xhci, { unsigned long long timeout_ns;

- 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; @@ -4633,7 +4633,7 @@ static u16 xhci_calculate_u2_timeout(struct xhci_hcd *xhci, { unsigned long long timeout_ns;

- 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; @@ -4738,12 +4738,42 @@ static int xhci_check_intel_tier_policy(struct usb_device *udev, return -E2BIG; }

+static int xhci_check_zhaoxin_tier_policy(struct usb_device *udev, + enum usb3_link_state state) +{ + struct usb_device *parent; + unsigned int num_hubs; + char *state_name; + + if (state == USB3_LPM_U1) + state_name = "U1"; + else if (state == USB3_LPM_U2) + state_name = "U2"; + else + state_name = "Unknown"; + /* Don't enable U1/U2 if the device is on an external hub*/ + for (parent = udev->parent, num_hubs = 0; parent->parent; + parent = parent->parent) + num_hubs++; + + if (num_hubs < 1) + return 0; + + dev_dbg(&udev->dev, "Disabling %s link state for device" \ + " below external hub.\n", state_name); + dev_dbg(&udev->dev, "Plug device into root port " \ + "to decrease power consumption.\n"); + 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 if (xhci->quirks & XHCI_ZHAOXIN_HOST) + return xhci_check_zhaoxin_tier_policy(udev, state); else return 0; } diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h index 7a4195f8cd1c..069390a1f2ac 100644 --- a/drivers/usb/host/xhci.h +++ b/drivers/usb/host/xhci.h @@ -1872,6 +1872,7 @@ struct xhci_hcd { #define XHCI_ZERO_64B_REGS BIT_ULL(32) #define XHCI_RESET_PLL_ON_DISCONNECT BIT_ULL(34) #define XHCI_SNPS_BROKEN_SUSPEND BIT_ULL(35) +#define XHCI_ZHAOXIN_HOST BIT_ULL(36) #define XHCI_DISABLE_SPARSE BIT_ULL(38)

unsigned int num_active_eps;