--- zzzz-none-000/linux-4.4.60/drivers/pci/pci-sysfs.c	2017-04-08 07:53:53.000000000 +0000
+++ scorpion-7490-727/linux-4.4.60/drivers/pci/pci-sysfs.c	2021-02-04 17:41:59.000000000 +0000
@@ -321,8 +321,32 @@
 }
 static BUS_ATTR(rescan, (S_IWUSR|S_IWGRP), NULL, bus_rescan_store);
 
+#ifdef CONFIG_AVM_PCI_RECOVERY
+static ssize_t bus_down_store(struct bus_type *bus, const char *buf,
+				size_t count)
+{
+	ath_pci_down();
+
+	return count;
+}
+static BUS_ATTR(down, (S_IWUSR|S_IWGRP), NULL, bus_down_store);
+
+static ssize_t bus_up_store(struct bus_type *bus, const char *buf,
+				size_t count)
+{
+	ath_pci_up();
+
+	return count;
+}
+static BUS_ATTR(up, (S_IWUSR|S_IWGRP), NULL, bus_up_store);
+#endif
+
 static struct attribute *pci_bus_attrs[] = {
 	&bus_attr_rescan.attr,
+#ifdef CONFIG_AVM_PCI_RECOVERY
+	&bus_attr_down.attr,
+	&bus_attr_up.attr,
+#endif
 	NULL,
 };
 
@@ -522,7 +546,7 @@
 				     const char *buf, size_t count)
 {
 	struct pci_dev *pdev = to_pci_dev(dev);
-	char *driver_override, *old = pdev->driver_override, *cp;
+	char *driver_override, *old, *cp;
 
 	/* We need to keep extra room for a newline */
 	if (count >= (PAGE_SIZE - 1))
@@ -536,12 +560,15 @@
 	if (cp)
 		*cp = '\0';
 
+	device_lock(dev);
+	old = pdev->driver_override;
 	if (strlen(driver_override)) {
 		pdev->driver_override = driver_override;
 	} else {
 		kfree(driver_override);
 		pdev->driver_override = NULL;
 	}
+	device_unlock(dev);
 
 	kfree(old);
 
@@ -552,8 +579,12 @@
 				    struct device_attribute *attr, char *buf)
 {
 	struct pci_dev *pdev = to_pci_dev(dev);
+	ssize_t len;
 
-	return snprintf(buf, PAGE_SIZE, "%s\n", pdev->driver_override);
+	device_lock(dev);
+	len = snprintf(buf, PAGE_SIZE, "%s\n", pdev->driver_override);
+	device_unlock(dev);
+	return len;
 }
 static DEVICE_ATTR_RW(driver_override);