[PATCH] USB: add reboot notifier to ohci

Adds a reboot notifier to OHCI, mostly to benefit kexec; plus
minor #include tweaks.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/host/ohci-hcd.c

@@ -95,12 +95,11 @@
 #include <linux/init.h>
 #include <linux/timer.h>
 #include <linux/list.h>
-#include <linux/interrupt.h>  /* for in_interrupt () */
 #include <linux/usb.h>
 #include <linux/usb_otg.h>
-#include "../core/hcd.h"
 #include <linux/dma-mapping.h> 
-#include <linux/dmapool.h>    /* needed by ohci-mem.c when no PCI */
+#include <linux/dmapool.h>
+#include <linux/reboot.h>
 
 #include <asm/io.h>
 #include <asm/irq.h>
@@ -108,8 +107,9 @@
 #include <asm/unaligned.h>
 #include <asm/byteorder.h>
 
+#include "../core/hcd.h"
 
-#define DRIVER_VERSION "2004 Nov 08"
+#define DRIVER_VERSION "2005 April 22"
 #define DRIVER_AUTHOR "Roman Weissgaerber, David Brownell"
 #define DRIVER_DESC "USB 1.1 'Open' Host Controller (OHCI) Driver"
 
@@ -141,6 +141,7 @@ static const char	hcd_name [] = "ohci_hcd";
 static void ohci_dump (struct ohci_hcd *ohci, int verbose);
 static int ohci_init (struct ohci_hcd *ohci);
 static void ohci_stop (struct usb_hcd *hcd);
+static int ohci_reboot (struct notifier_block *, unsigned long , void *);
 
 #include "ohci-hub.c"
 #include "ohci-dbg.c"
@@ -420,6 +421,23 @@ static void ohci_usb_reset (struct ohci_hcd *ohci)
 	ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
 }
 
+/* reboot notifier forcibly disables IRQs and DMA, helping kexec and
+ * other cases where the next software may expect clean state from the
+ * "firmware".  this is bus-neutral, unlike shutdown() methods.
+ */
+static int
+ohci_reboot (struct notifier_block *block, unsigned long code, void *null)
+{
+	struct ohci_hcd *ohci;
+
+	ohci = container_of (block, struct ohci_hcd, reboot_notifier);
+	ohci_writel (ohci, OHCI_INTR_MIE, &ohci->regs->intrdisable);
+	ohci_usb_reset (ohci);
+	/* flush the writes */
+	(void) ohci_readl (ohci, &ohci->regs->control);
+	return 0;
+}
+
 /*-------------------------------------------------------------------------*
  * HC functions
  *-------------------------------------------------------------------------*/
@@ -684,6 +702,7 @@ retry:
 	if (ohci->power_budget)
 		hub_set_power_budget(udev, ohci->power_budget);
 
+	register_reboot_notifier (&ohci->reboot_notifier);
 	create_debug_files (ohci);
 	return 0;
 }
@@ -781,6 +800,7 @@ static void ohci_stop (struct usb_hcd *hcd)
 	ohci_writel (ohci, OHCI_INTR_MIE, &ohci->regs->intrdisable);
 	
 	remove_debug_files (ohci);
+	unregister_reboot_notifier (&ohci->reboot_notifier);
 	ohci_mem_cleanup (ohci);
 	if (ohci->hcca) {
 		dma_free_coherent (hcd->self.controller, 

drivers/usb/host/ohci-mem.c

@@ -29,6 +29,7 @@ static void ohci_hcd_init (struct ohci_hcd *ohci)
 	spin_lock_init (&ohci->lock);
 	INIT_LIST_HEAD (&ohci->pending);
 	INIT_WORK (&ohci->rh_resume, ohci_rh_resume, ohci_to_hcd(ohci));
+	ohci->reboot_notifier.notifier_call = ohci_reboot;
 }
 
 /*-------------------------------------------------------------------------*/

drivers/usb/host/ohci.h

@@ -390,6 +390,7 @@ struct ohci_hcd {
 	u32			fminterval;		/* saved register */
 
 	struct work_struct	rh_resume;
+	struct notifier_block	reboot_notifier;
 
 	unsigned long		flags;		/* for HC bugs */
 #define	OHCI_QUIRK_AMD756	0x01			/* erratum #4 */