USB: EHCI: log a warning if ehci-hcd is not loaded first
This patch (as1139) adds a warning to the system log whenever ehci-hcd
is loaded after ohci-hcd or uhci-hcd. Nowadays most distributions are
pretty good about not doing this; maybe the warning will help convince
anyone still doing it wrong.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Cc: stable <stable@kernel.org> [2.6.27]
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c
index c8035a8..fc9018e 100644
--- a/drivers/usb/core/hcd.c
+++ b/drivers/usb/core/hcd.c
@@ -81,6 +81,10 @@
/*-------------------------------------------------------------------------*/
+/* Keep track of which host controller drivers are loaded */
+unsigned long usb_hcds_loaded;
+EXPORT_SYMBOL_GPL(usb_hcds_loaded);
+
/* host controllers we manage */
LIST_HEAD (usb_bus_list);
EXPORT_SYMBOL_GPL (usb_bus_list);
diff --git a/drivers/usb/core/hcd.h b/drivers/usb/core/hcd.h
index e710ce0..2dcde61 100644
--- a/drivers/usb/core/hcd.h
+++ b/drivers/usb/core/hcd.h
@@ -482,4 +482,10 @@
*/
extern struct rw_semaphore ehci_cf_port_reset_rwsem;
+/* Keep track of which host controller drivers are loaded */
+#define USB_UHCI_LOADED 0
+#define USB_OHCI_LOADED 1
+#define USB_EHCI_LOADED 2
+extern unsigned long usb_hcds_loaded;
+
#endif /* __KERNEL__ */
diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c
index fcbc1f2..358df2a 100644
--- a/drivers/usb/host/ehci-hcd.c
+++ b/drivers/usb/host/ehci-hcd.c
@@ -1046,6 +1046,12 @@
return -ENODEV;
printk(KERN_INFO "%s: " DRIVER_DESC "\n", hcd_name);
+ set_bit(USB_EHCI_LOADED, &usb_hcds_loaded);
+ if (test_bit(USB_UHCI_LOADED, &usb_hcds_loaded) ||
+ test_bit(USB_OHCI_LOADED, &usb_hcds_loaded))
+ printk(KERN_WARNING "Warning! ehci_hcd should always be loaded"
+ " before uhci_hcd and ohci_hcd, not after\n");
+
pr_debug("%s: block sizes: qh %Zd qtd %Zd itd %Zd sitd %Zd\n",
hcd_name,
sizeof(struct ehci_qh), sizeof(struct ehci_qtd),
@@ -1053,8 +1059,10 @@
#ifdef DEBUG
ehci_debug_root = debugfs_create_dir("ehci", NULL);
- if (!ehci_debug_root)
- return -ENOENT;
+ if (!ehci_debug_root) {
+ retval = -ENOENT;
+ goto err_debug;
+ }
#endif
#ifdef PLATFORM_DRIVER
@@ -1102,6 +1110,8 @@
debugfs_remove(ehci_debug_root);
ehci_debug_root = NULL;
#endif
+err_debug:
+ clear_bit(USB_EHCI_LOADED, &usb_hcds_loaded);
return retval;
}
module_init(ehci_hcd_init);
@@ -1123,6 +1133,7 @@
#ifdef DEBUG
debugfs_remove(ehci_debug_root);
#endif
+ clear_bit(USB_EHCI_LOADED, &usb_hcds_loaded);
}
module_exit(ehci_hcd_cleanup);
diff --git a/drivers/usb/host/ohci-hcd.c b/drivers/usb/host/ohci-hcd.c
index 0afeda836..8647dab 100644
--- a/drivers/usb/host/ohci-hcd.c
+++ b/drivers/usb/host/ohci-hcd.c
@@ -1095,6 +1095,7 @@
printk(KERN_INFO "%s: " DRIVER_DESC "\n", hcd_name);
pr_debug ("%s: block sizes: ed %Zd td %Zd\n", hcd_name,
sizeof (struct ed), sizeof (struct td));
+ set_bit(USB_OHCI_LOADED, &usb_hcds_loaded);
#ifdef DEBUG
ohci_debug_root = debugfs_create_dir("ohci", NULL);
@@ -1181,6 +1182,7 @@
error_debug:
#endif
+ clear_bit(USB_OHCI_LOADED, &usb_hcds_loaded);
return retval;
}
module_init(ohci_hcd_mod_init);
@@ -1211,6 +1213,7 @@
#ifdef DEBUG
debugfs_remove(ohci_debug_root);
#endif
+ clear_bit(USB_OHCI_LOADED, &usb_hcds_loaded);
}
module_exit(ohci_hcd_mod_exit);
diff --git a/drivers/usb/host/uhci-hcd.c b/drivers/usb/host/uhci-hcd.c
index 2dddb25..cf5e4cf 100644
--- a/drivers/usb/host/uhci-hcd.c
+++ b/drivers/usb/host/uhci-hcd.c
@@ -955,6 +955,7 @@
printk(KERN_INFO "uhci_hcd: " DRIVER_DESC "%s\n",
ignore_oc ? ", overcurrent ignored" : "");
+ set_bit(USB_UHCI_LOADED, &usb_hcds_loaded);
if (DEBUG_CONFIGURED) {
errbuf = kmalloc(ERRBUF_LEN, GFP_KERNEL);
@@ -987,6 +988,7 @@
errbuf_failed:
+ clear_bit(USB_UHCI_LOADED, &usb_hcds_loaded);
return retval;
}
@@ -996,6 +998,7 @@
kmem_cache_destroy(uhci_up_cachep);
debugfs_remove(uhci_debugfs_root);
kfree(errbuf);
+ clear_bit(USB_UHCI_LOADED, &usb_hcds_loaded);
}
module_init(uhci_hcd_init);