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2024-02-20 102a0743326a03cd1a1202ceda21e175b7d3575c

 kernel/drivers/usb/core/usb-acpi.c
..
..
@@ -37,6 +37,71 @@
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 }
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 EXPORT_SYMBOL_GPL(usb_acpi_power_manageable);
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+#define UUID_USB_CONTROLLER_DSM "ce2ee385-00e6-48cb-9f05-2edb927c4899"
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+#define USB_DSM_DISABLE_U1_U2_FOR_PORT	5
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+
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+/**
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+ * usb_acpi_port_lpm_incapable - check if lpm should be disabled for a port.
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+ * @hdev: USB device belonging to the usb hub
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+ * @index: zero based port index
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+ *
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+ * Some USB3 ports may not support USB3 link power management U1/U2 states
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+ * due to different retimer setup. ACPI provides _DSM method which returns 0x01
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+ * if U1 and U2 states should be disabled. Evaluate _DSM with:
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+ * Arg0: UUID = ce2ee385-00e6-48cb-9f05-2edb927c4899
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+ * Arg1: Revision ID = 0
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+ * Arg2: Function Index = 5
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+ * Arg3: (empty)
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+ *
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+ * Return 1 if USB3 port is LPM incapable, negative on error, otherwise 0
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+ */
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+
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+int usb_acpi_port_lpm_incapable(struct usb_device *hdev, int index)
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+{
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+	union acpi_object *obj;
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+	acpi_handle port_handle;
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+	int port1 = index + 1;
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+	guid_t guid;
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+	int ret;
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+
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+	ret = guid_parse(UUID_USB_CONTROLLER_DSM, &guid);
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+	if (ret)
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+		return ret;
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+
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+	port_handle = usb_get_hub_port_acpi_handle(hdev, port1);
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+	if (!port_handle) {
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+		dev_dbg(&hdev->dev, "port-%d no acpi handle\n", port1);
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+		return -ENODEV;
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+	}
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+
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+	if (!acpi_check_dsm(port_handle, &guid, 0,
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+			    BIT(USB_DSM_DISABLE_U1_U2_FOR_PORT))) {
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+		dev_dbg(&hdev->dev, "port-%d no _DSM function %d\n",
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+			port1, USB_DSM_DISABLE_U1_U2_FOR_PORT);
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+		return -ENODEV;
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+	}
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+
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+	obj = acpi_evaluate_dsm(port_handle, &guid, 0,
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+				USB_DSM_DISABLE_U1_U2_FOR_PORT, NULL);
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+
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+	if (!obj)
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+		return -ENODEV;
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+
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+	if (obj->type != ACPI_TYPE_INTEGER) {
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+		dev_dbg(&hdev->dev, "evaluate port-%d _DSM failed\n", port1);
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+		ACPI_FREE(obj);
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+		return -EINVAL;
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+	}
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+
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+	if (obj->integer.value == 0x01)
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+		ret = 1;
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+
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+	ACPI_FREE(obj);
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+
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+	return ret;
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+}
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+EXPORT_SYMBOL_GPL(usb_acpi_port_lpm_incapable);
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+
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 /**
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  * usb_acpi_set_power_state - control usb port's power via acpi power
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  * resource