openwrtv4/target/linux/generic/patches-3.18/140-mtd-part-add-generic-parsing-of-linux-part-probe.patch
John Crispin 6856535e29 kernel: move linux, part-probe dt parsing in generic code
The "linux,part-probe" dts parsing is a pretty neat generic feature.
It has been posted to kernel.org and could easily be reused by all
targets.

This change moves the patch to the 3.18 and 4.1 generic folders, and
makes the feature available to all platforms who may want to use it.

Signed-off-by: Mathieu Olivari <mathieu@codeaurora.org>
Acked-by: Hauke Mehrtens <hauke@hauke-m.de>

SVN-Revision: 46654
2015-08-17 06:17:37 +00:00

175 lines
4.8 KiB
Diff

From 173b0add0cff6558f950c0cb1eacfb729d482711 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 4/8] 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 | 40 +-----------------------
drivers/mtd/mtdpart.c | 43 ++++++++++++++++++++++++++
3 files changed, 60 insertions(+), 39 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
@@ -114,45 +114,9 @@ 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);
- 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 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;
@@ -302,10 +266,8 @@ static int of_flash_probe(struct platfor
goto err_out;
ppdata.of_node = dp;
- part_probe_types = of_get_probes(dp);
- 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 "mtdcore.h"
@@ -702,6 +703,40 @@ 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);
+ 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!
*/
@@ -737,6 +772,13 @@ int parse_mtd_partitions(struct mtd_info
{
struct mtd_part_parser *parser;
int ret = 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;
@@ -755,6 +797,7 @@ int parse_mtd_partitions(struct mtd_info
break;
}
}
+ kfree(types_of);
return ret;
}