From 944803d916abb1b39d0cce1589614e0152d2bfa3 Mon Sep 17 00:00:00 2001
From: Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
Date: Wed, 11 Oct 2023 16:33:25 +0200
Subject: [PATCH] rules: add mtd/by-name symlinks

Add persistent symlinks for MTD devices like SPI-NOR flash, based on the
partition names specified on the cmdline, in a Device Tree, or by other
MTD partitioning parser drivers. Using the persistent name can be
preferable to using the numbered /dev/mtdX device, as the latter can
change depending on probe order or when partitioning has changed.
---
 rules/60-persistent-storage-mtd.rules | 12 ++++++++++++
 rules/Makefile.am                     |  1 +
 2 files changed, 13 insertions(+)
 create mode 100644 rules/60-persistent-storage-mtd.rules

diff --git a/rules/60-persistent-storage-mtd.rules b/rules/60-persistent-storage-mtd.rules
new file mode 100644
index 000000000..bcf93b9a0
--- /dev/null
+++ b/rules/60-persistent-storage-mtd.rules
@@ -0,0 +1,12 @@
+# do not edit this file, it will be overwritten on update
+
+# persistent storage links: /dev/mtd/by-name
+
+ACTION=="remove", GOTO="persistent_storage_mtd_end"
+SUBSYSTEM!="mtd", GOTO="persistent_storage_mtd_end"
+KERNEL!="mtd[0-9]*", GOTO="persistent_storage_mtd_end"
+KERNEL=="mtd[0-9]*ro", GOTO="persistent_storage_mtd_end"
+
+ATTR{name}=="?*", SYMLINK+="mtd/by-name/$attr{name}"
+
+LABEL="persistent_storage_mtd_end"
diff --git a/rules/Makefile.am b/rules/Makefile.am
index fcef039fe..5f4993098 100644
--- a/rules/Makefile.am
+++ b/rules/Makefile.am
@@ -17,6 +17,7 @@ dist_udevrules_DATA = \
 	60-input-id.rules \
 	60-persistent-alsa.rules \
 	60-persistent-input.rules \
+	60-persistent-storage-mtd.rules \
 	60-persistent-storage-tape.rules \
 	60-persistent-v4l.rules \
 	60-sensor.rules \