kernel: fix NVMEM looking for OTP NVMEM cells in wrong DT node

It was breaking NAND controllers drivers.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>

diff --git a/target/linux/generic/pending-6.6/440-mtd-don-t-look-for-OTP-legacy-NVMEM-cells-if-proper-.patch b/target/linux/generic/pending-6.6/440-mtd-don-t-look-for-OTP-legacy-NVMEM-cells-if-proper-.patch
new file mode 100644 (file)
index 0000000..d9d15a4
--- /dev/null
+++ b/target/linux/generic/pending-6.6/440-mtd-don-t-look-for-OTP-legacy-NVMEM-cells-if-proper-.patch
@@ -0,0 +1,44 @@
+From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <rafal@milecki.pl>
+Date: Wed, 27 Mar 2024 23:18:51 +0100
+Subject: [PATCH] mtd: don't look for OTP legacy NVMEM cells if proper node
+ doesn't exist
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+If node with "user-otp" / "factory-otp" compatible doesn't exist it's
+important to prevent NVMEM core from looking for legacy NVMEM cells.
+Otherwise it would look for them in the device node.
+
+This fixes treating NAND controller attached chips as NVMEM cell.
+Problem example:
+[    0.410107] nand: device found, Manufacturer ID: 0xc2, Chip ID: 0xdc
+[    0.416531] nand: Macronix MX30LF4G18AC
+[    0.420409] nand: 512 MiB, SLC, erase size: 128 KiB, page size: 2048, OOB size: 64
+[    0.428022] iproc_nand 18028000.nand-controller: detected 512MiB total, 128KiB blocks, 2KiB pages, 16B OOB, 8-bit, BCH-8
+[    0.438991] Scanning device for bad blocks
+(...)
+[    2.848418] nvmem user-otp1: nvmem: invalid reg on /nand-controller@18028000/nand@0
+[    2.856126] iproc_nand 18028000.nand-controller: error -EINVAL: Failed to register OTP NVMEM device
+
+This long standing issue was exposed by the support for Macronix OTP.
+
+Reported-by: Christian Marangi <ansuelsmth@gmail.com>
+Fixes: 4b361cfa8624 ("mtd: core: add OTP nvmem provider support")
+Fixes: e87161321a40 ("mtd: rawnand: macronix: OTP access for MX30LFxG18AC")
+Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
+---
+ drivers/mtd/mtdcore.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+--- a/drivers/mtd/mtdcore.c
++++ b/drivers/mtd/mtdcore.c
+@@ -931,7 +931,7 @@ static struct nvmem_device *mtd_otp_nvme
+       config.name = compatible;
+       config.id = NVMEM_DEVID_AUTO;
+       config.owner = THIS_MODULE;
+-      config.add_legacy_fixed_of_cells = true;
++      config.add_legacy_fixed_of_cells = !!np;
+       config.type = NVMEM_TYPE_OTP;
+       config.root_only = true;
+       config.ignore_wp = true;