openwrt/target/linux/generic/pending-4.4/140-mtd-part-add-generic-parsing-of-linux-part-probe.patch

From 3e7056c3a369e9ef9ca804bc626b60ef6b62ee27 Mon Sep 17 00:00:00 2001
From: Hauke Mehrtens <hauke@hauke-m.de>
Date: Sun, 17 May 2015 18:48:38 +0200
Subject: [PATCH 2/3] mtd: part: add generic parsing of linux,part-probe

This moves the linux,part-probe device tree parsing code from
physmap_of.c to mtdpart.c. Now all drivers can use this feature by just
providing a reference to their device tree node in struct
mtd_part_parser_data.

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
---
 Documentation/devicetree/bindings/mtd/nand.txt | 16 +++++++++
 drivers/mtd/maps/physmap_of.c                  | 46 +-------------------------
 drivers/mtd/mtdpart.c                          | 45 +++++++++++++++++++++++++
 3 files changed, 62 insertions(+), 45 deletions(-)

--- a/Documentation/devicetree/bindings/mtd/nand.txt
+++ b/Documentation/devicetree/bindings/mtd/nand.txt
@@ -12,6 +12,22 @@
 - nand-ecc-step-size: integer representing the number of data bytes
 		      that are covered by a single ECC step.
 
+- linux,part-probe: list of name as strings of the partition parser
+		    which should be used to parse the partition table.
+		    They will be tried in the specified ordering and
+		    the next one will be used if the previous one
+		    failed.
+
+		    Example: linux,part-probe = "cmdlinepart", "ofpart";
+
+		    This is also the default value, which will be used
+		    if this attribute is not specified. It could be
+		    that the flash driver in use overwrote the default
+		    value and uses some other default.
+
+		    Possible values are: bcm47xxpart, afs, ar7part,
+		    ofoldpart, ofpart, bcm63xxpart, RedBoot, cmdlinepart
+
 The ECC strength and ECC step size properties define the correction capability
 of a controller. Together, they say a controller can correct "{strength} bit
 errors per {size} bytes".
--- a/drivers/mtd/maps/physmap_of.c
+++ b/drivers/mtd/maps/physmap_of.c
@@ -112,47 +112,9 @@ static struct mtd_info *obsolete_probe(s
 static const char * const part_probe_types_def[] = {
 	"cmdlinepart", "RedBoot", "ofpart", "ofoldpart", NULL };
 
-static const char * const *of_get_probes(struct device_node *dp)
-{
-	const char *cp;
-	int cplen;
-	unsigned int l;
-	unsigned int count;
-	const char **res;
-
-	cp = of_get_property(dp, "linux,part-probe", &cplen);
-	if (cp == NULL)
-		return part_probe_types_def;
-
-	count = 0;
-	for (l = 0; l != cplen; l++)
-		if (cp[l] == 0)
-			count++;
-
-	res = kzalloc((count + 1)*sizeof(*res), GFP_KERNEL);
-	if (!res)
-		return NULL;
-	count = 0;
-	while (cplen > 0) {
-		res[count] = cp;
-		l = strlen(cp) + 1;
-		cp += l;
-		cplen -= l;
-		count++;
-	}
-	return res;
-}
-
-static void of_free_probes(const char * const *probes)
-{
-	if (probes != part_probe_types_def)
-		kfree(probes);
-}
-
 static const struct of_device_id of_flash_match[];
 static int of_flash_probe(struct platform_device *dev)
 {
-	const char * const *part_probe_types;
 	const struct of_device_id *match;
 	struct device_node *dp = dev->dev.of_node;
 	struct resource res;
@@ -311,14 +273,8 @@ static int of_flash_probe(struct platfor
 		goto err_out;
 
 	ppdata.of_node = dp;
-	part_probe_types = of_get_probes(dp);
-	if (!part_probe_types) {
-		err = -ENOMEM;
-		goto err_out;
-	}
-	mtd_device_parse_register(info->cmtd, part_probe_types, &ppdata,
+	mtd_device_parse_register(info->cmtd, part_probe_types_def, &ppdata,
 			NULL, 0);
-	of_free_probes(part_probe_types);
 
 	kfree(mtd_list);
 
--- a/drivers/mtd/mtdpart.c
+++ b/drivers/mtd/mtdpart.c
@@ -29,6 +29,7 @@
 #include <linux/kmod.h>
 #include <linux/mtd/mtd.h>
 #include <linux/mtd/partitions.h>
+#include <linux/of.h>
 #include <linux/err.h>
 #include <linux/kconfig.h>
 
@@ -721,6 +722,42 @@ void deregister_mtd_parser(struct mtd_pa
 EXPORT_SYMBOL_GPL(deregister_mtd_parser);
 
 /*
+ * Parses the linux,part-probe device tree property.
+ * When a non null value is returned it has to be freed with kfree() by
+ * the caller.
+ */
+static const char * const *of_get_probes(struct device_node *dp)
+{
+	const char *cp;
+	int cplen;
+	unsigned int l;
+	unsigned int count;
+	const char **res;
+
+	cp = of_get_property(dp, "linux,part-probe", &cplen);
+	if (cp == NULL)
+		return NULL;
+
+	count = 0;
+	for (l = 0; l != cplen; l++)
+		if (cp[l] == 0)
+			count++;
+
+	res = kzalloc((count + 1) * sizeof(*res), GFP_KERNEL);
+	if (!res)
+		return NULL;
+	count = 0;
+	while (cplen > 0) {
+		res[count] = cp;
+		l = strlen(cp) + 1;
+		cp += l;
+		cplen -= l;
+		count++;
+	}
+	return res;
+}
+
+/*
  * Do not forget to update 'parse_mtd_partitions()' kerneldoc comment if you
  * are changing this array!
  */
@@ -756,6 +793,13 @@ int parse_mtd_partitions(struct mtd_info
 {
 	struct mtd_part_parser *parser;
 	int ret, err = 0;
+	const char *const *types_of = NULL;
+
+	if (data && data->of_node) {
+		types_of = of_get_probes(data->of_node);
+		if (types_of != NULL)
+			types = types_of;
+	}
 
 	if (!types)
 		types = default_mtd_part_types;
@@ -785,6 +829,7 @@ int parse_mtd_partitions(struct mtd_info
 		if (ret < 0 && !err)
 			err = ret;
 	}
+	kfree(types_of);
 	return err;
 }