Force Dell MD1200 / MD1220 enclosures as SES-enabled, e.g. /sys/class/enclosure/

md12xx-ses.patch

From f9e8eaf3226009531b769635a6114f87da08291b Mon Sep 17 00:00:00 2001
From: "Jason R. McNeil" <[email protected]>
Date: Wed, 12 May 2021 01:16:35 -0700
Subject: [PATCH] drivers/scsi/ses: Dell MD12XX enclosures support SES, despite
 EncServ=0 as claimed by the device

---
 drivers/scsi/ses.c | 26 +++++++++++++++++++++++---
 1 file changed, 23 insertions(+), 3 deletions(-)

diff --git a/drivers/scsi/ses.c b/drivers/scsi/ses.c
index c2afba2a5..cfb7b6a39 100644
--- a/drivers/scsi/ses.c
+++ b/drivers/scsi/ses.c
@@ -620,6 +620,26 @@ static void ses_match_to_enclosure(struct enclosure_device *edev,
 	}
 }
 
+static int ses_device_enclosure(struct scsi_device *sdev)
+{
+	int sde = scsi_device_enclosure(sdev);
+	if (sde)
+		return sde;
+
+	if (sdev->type != TYPE_ENCLOSURE)
+		return 0;
+
+	if (strncmp(sdev->vendor, "DELL ", 5) == 0) {
+		if ((strncmp(sdev->model, "MD1200 ", 7) == 0)
+				|| (strncmp(sdev->model, "MD1220 ", 7) == 0)) {
+				sdev_printk(KERN_NOTICE, sdev, "Enclosure supports SES, ignoring EncServ=0 as claimed by the device\n");
+				return 1;
+		}
+	}
+
+	return 0;
+}
+
 static int ses_intf_add(struct device *cdev,
 			struct class_interface *intf)
 {
@@ -634,7 +654,7 @@ static int ses_intf_add(struct device *cdev,
 	struct enclosure_device *edev;
 	struct ses_component *scomp = NULL;
 
-	if (!scsi_device_enclosure(sdev)) {
+	if (!ses_device_enclosure(sdev)) {
 		/* not an enclosure, but might be in one */
 		struct enclosure_device *prev = NULL;
 
@@ -753,7 +773,7 @@ static int ses_intf_add(struct device *cdev,
 	/* see if there are any devices matching before
 	 * we found the enclosure */
 	shost_for_each_device(tmp_sdev, sdev->host) {
-		if (tmp_sdev->lun != 0 || scsi_device_enclosure(tmp_sdev))
+		if (tmp_sdev->lun != 0 || ses_device_enclosure(tmp_sdev))
 			continue;
 		ses_match_to_enclosure(edev, tmp_sdev, 0);
 	}
@@ -824,7 +844,7 @@ static void ses_intf_remove(struct device *cdev,
 {
 	struct scsi_device *sdev = to_scsi_device(cdev->parent);
 
-	if (!scsi_device_enclosure(sdev))
+	if (!ses_device_enclosure(sdev))
 		ses_intf_remove_component(sdev);
 	else
 		ses_intf_remove_enclosure(sdev);
-- 
2.31.1

nix-kernel.sh

nix-build '<nixpkgs>' -A linuxPackages_latest.kernel.dev
nix-shell '<nixpkgs>' -A linuxPackages_latest.kernel
# $ unpackPhase
# $ cd linux-*

nix-reload.sh

lsmod | grep -E '(ses|enclosure)'

rmmod ses
rmmod enclosure

make -C $dev/lib/modules/*/build M=$(pwd)/drivers/scsi ses.ko || exit 1
make -C $dev/lib/modules/*/build M=$(pwd)/drivers/misc enclosure.ko || exit 1

insmod ./drivers/misc/enclosure.ko
insmod ./drivers/scsi/ses.ko

lsmod | grep -E '(ses|enclosure)'

ls -la /sys/class/enclosure/