kernel: backport mtd patch adding of_platform_populate() calls

[openwrt/openwrt.git] / target / linux / generic / backport-5.10 / 412-v5.19-mtd-call-of_platform_populate-for-MTD-partitions.patch

diff --git a/target/linux/generic/backport-5.10/412-v5.19-mtd-call-of_platform_populate-for-MTD-partitions.patch b/target/linux/generic/backport-5.10/412-v5.19-mtd-call-of_platform_populate-for-MTD-partitions.patch
new file mode 100644 (file)
index 0000000..aaeb087
--- /dev/null
+++ b/target/linux/generic/backport-5.10/412-v5.19-mtd-call-of_platform_populate-for-MTD-partitions.patch
@@ -0,0 +1,72 @@
+From bcdf0315a61a29eb753a607d3a85a4032de72d94 Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <rafal@milecki.pl>
+Date: Tue, 10 May 2022 15:12:59 +0200
+Subject: [PATCH] mtd: call of_platform_populate() for MTD partitions
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+Until this change MTD subsystem supported handling partitions only with
+MTD partitions parsers. That's a specific / limited API designed around
+partitions.
+
+Some MTD partitions may however require different handling. They may
+contain specific data that needs to be parsed and somehow extracted. For
+that purpose MTD subsystem should allow binding of standard platform
+drivers.
+
+An example can be U-Boot (sub)partition with environment variables.
+There exist a "u-boot,env" DT binding for MTD (sub)partition that
+requires an NVMEM driver.
+
+Ref: 5db1c2dbc04c ("dt-bindings: nvmem: add U-Boot environment variables binding")
+Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
+Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
+Link: https://lore.kernel.org/linux-mtd/20220510131259.555-1-zajec5@gmail.com
+---
+ drivers/mtd/mtdpart.c | 9 +++++++++
+ 1 file changed, 9 insertions(+)
+
+--- a/drivers/mtd/mtdpart.c
++++ b/drivers/mtd/mtdpart.c
+@@ -17,6 +17,7 @@
+ #include <linux/mtd/partitions.h>
+ #include <linux/err.h>
+ #include <linux/of.h>
++#include <linux/of_platform.h>
+ 
+ #include "mtdcore.h"
+ 
+@@ -578,10 +579,16 @@ static int mtd_part_of_parse(struct mtd_
+       struct mtd_part_parser *parser;
+       struct device_node *np;
+       struct property *prop;
++      struct device *dev;
+       const char *compat;
+       const char *fixed = "fixed-partitions";
+       int ret, err = 0;
+ 
++      dev = &master->dev;
++      /* Use parent device (controller) if the top level MTD is not registered */
++      if (!IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER) && !mtd_is_partition(master))
++              dev = master->dev.parent;
++
+       np = mtd_get_of_node(master);
+       if (mtd_is_partition(master))
+               of_node_get(np);
+@@ -594,6 +601,7 @@ static int mtd_part_of_parse(struct mtd_
+                       continue;
+               ret = mtd_part_do_parse(parser, master, pparts, NULL);
+               if (ret > 0) {
++                      of_platform_populate(np, NULL, NULL, dev);
+                       of_node_put(np);
+                       return ret;
+               }
+@@ -601,6 +609,7 @@ static int mtd_part_of_parse(struct mtd_
+               if (ret < 0 && !err)
+                       err = ret;
+       }
++      of_platform_populate(np, NULL, NULL, dev);
+       of_node_put(np);
+ 
+       /*