ide: Stop disks on reboot for laptop which cuts power

My laptop (Acer Travelmate 660) always cuts the power when rebooting
which causes the disk to emergency-park it's head.

Add a dmi check to stop disk as for shutdown on this laptop.

Signed-off-by: Bruno Prémont <[e-mail]>
Cc: Jeff Garzik <[e-mail]>
Signed-off-by: Bartlomiej Zolnierkiewicz <[e-mail]>

drivers/ide/ide-gd.c

···
 #include <linux/mutex.h>
 #include <linux/ide.h>
 #include <linux/hdreg.h>
+#include <linux/dmi.h>
 
 #if !defined(CONFIG_DEBUG_BLOCK_EXT_DEVT)
 #define IDE_DISK_MINORS		(1 << PARTN_BITS)
···
 		(void)drive->disk_ops->get_capacity(drive);
 }
 
+static const struct dmi_system_id ide_coldreboot_table[] = {
+	{
+		/* Acer TravelMate 66x cuts power during reboot */
+		.ident   = "Acer TravelMate 660",
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "TravelMate 660"),
+		},
+	},
+
+	{ }	/* terminate list */
+};
+
 static void ide_gd_shutdown(ide_drive_t *drive)
 {
 #ifdef	CONFIG_ALPHA
···
 	   the disk to expire its write cache. */
 	if (system_state != SYSTEM_POWER_OFF) {
 #else
-	if (system_state == SYSTEM_RESTART) {
+	if (system_state == SYSTEM_RESTART &&
+		!dmi_check_system(ide_coldreboot_table)) {
 #endif
 		drive->disk_ops->flush(drive);
 		return;