[PATCH 2/2] sd: Stop disks on reboot for laptop which cuts power

["Bruno Prémont" <bonbons@linux-vserver.org>]

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 <bonbons@linux-vserver.org>
---
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 3fcb64b..fdad8bc 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -50,6 +50,7 @@
 #include <linux/string_helpers.h>
 #include <linux/async.h>
 #include <asm/uaccess.h>
+#include <linux/dmi.h>
 
 #include <scsi/scsi.h>
 #include <scsi/scsi_cmnd.h>
@@ -2127,6 +2128,20 @@ static int sd_start_stop_device(struct scsi_disk *sdkp, int start)
 	return res;
 }
 
+static const struct dmi_system_id sd_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 */
+};
+
+
 /*
  * Send a SYNCHRONIZE CACHE instruction down to the device through
  * the normal SCSI command structure.  Wait for the command to
@@ -2144,7 +2159,9 @@ static void sd_shutdown(struct device *dev)
 		sd_sync_cache(sdkp);
 	}
 
-	if (system_state != SYSTEM_RESTART && sdkp->device->manage_start_stop) {
+	if (sdkp->device->manage_start_stop &&
+	    (system_state != SYSTEM_RESTART ||
+	    dmi_check_system(sd_coldreboot_table))) {
 		sd_printk(KERN_NOTICE, sdkp, "Stopping disk\n");
 		sd_start_stop_device(sdkp, 0);
 	}