xhci: Add Zhaoxin xHCI LPM U1/U2 feature support

zhaoxin inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I40QDN
CVE: NA

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Add LPM u1/u2 feature support for xHCI of zhaoxin
Signed-off-by: NLeoLiu-oc <LeoLiu-oc@zhaoxin.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>
Reviewed-by: NHanjun Guo <guohanjun@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

drivers/usb/host/xhci-pci.c

@@ -268,6 +268,10 @@ 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 &&

drivers/usb/host/xhci.c

@@ -4666,7 +4666,7 @@ 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;
@@ -4730,7 +4730,7 @@ 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;
@@ -4835,12 +4835,42 @@ 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;
 }

drivers/usb/host/xhci.h

@@ -1880,6 +1880,7 @@ struct xhci_hcd {
 #define XHCI_DISABLE_SPARSE	BIT_ULL(38)
 #define XHCI_SG_TRB_CACHE_SIZE_QUIRK	BIT_ULL(39)
 #define XHCI_NO_SOFT_RETRY	BIT_ULL(40)
+#define XHCI_ZHAOXIN_HOST	BIT_ULL(41)
 
 	unsigned int		num_active_eps;
 	unsigned int		limit_active_eps;