[PATCH 1/2 v3] pinctrl: make a copy of pinmux map
From: Linus Walleij
Date: Wed Nov 30 2011 - 07:33:26 EST
From: Linus Walleij <linus.walleij@xxxxxxxxxx>
This makes a deep copy of the pinmux function map instead of
keeping the copy supplied from the platform around. This makes
it possible to tag the platforms map with __initdata as is also
done as part of this patch.
Rationale: a certain target platform (PXA) has numerous
pinmux maps, many of which will be lying around unused after
boot in a multi-platform binary. Instead, deep-copy the one
we're going to use and tag them all __initdata so they go away
after boot.
ChangeLog v1->v2:
- Fixup the deep copy, missed a few items on the struct,
plus mark bool member non-const since we're making runtime
copies if this stuff now.
ChangeLog v2->v3:
- Make a shallow copy (just copy the array of map structs)
as Arnd noticed, string constants never get discarded by the
kernel anyway, so these pointers may be safely copied over.
Suggested-by: Arnd Bergmann <arnd.bergmann@xxxxxxxxxx>
Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
---
Documentation/pinctrl.txt | 4 +-
arch/arm/mach-u300/core.c | 2 +-
drivers/pinctrl/pinmux.c | 44 ++++++++++++++++++++++++++++++--------
include/linux/pinctrl/machine.h | 2 +-
4 files changed, 38 insertions(+), 14 deletions(-)
diff --git a/Documentation/pinctrl.txt b/Documentation/pinctrl.txt
index 720dfea..d9d57c8 100644
--- a/Documentation/pinctrl.txt
+++ b/Documentation/pinctrl.txt
@@ -784,7 +784,7 @@ spi on the second function mapping:
#include <linux/pinctrl/machine.h>
-static struct pinmux_map pmx_mapping[] = {
+static struct pinmux_map __initdata pmx_mapping[] = {
{
.ctrl_dev_name = "pinctrl.0",
.function = "spi0",
@@ -821,7 +821,7 @@ Since the above construct is pretty common there is a helper macro to make
it even more compact which assumes you want to use pinctrl.0 and position
0 for mapping, for example:
-static struct pinmux_map pmx_mapping[] = {
+static struct pinmux_map __initdata pmx_mapping[] = {
PINMUX_MAP_PRIMARY("I2CMAP", "i2c0", "foo-i2c.0"),
};
diff --git a/arch/arm/mach-u300/core.c b/arch/arm/mach-u300/core.c
index f399862..06bdae7 100644
--- a/arch/arm/mach-u300/core.c
+++ b/arch/arm/mach-u300/core.c
@@ -1613,7 +1613,7 @@ static struct platform_device pinmux_device = {
};
/* Pinmux settings */
-static struct pinmux_map u300_pinmux_map[] = {
+static struct pinmux_map __initdata u300_pinmux_map[] = {
/* anonymous maps for chip power and EMIFs */
PINMUX_MAP_PRIMARY_SYS_HOG("POWER", "power"),
PINMUX_MAP_PRIMARY_SYS_HOG("EMIF0", "emif0"),
diff --git a/drivers/pinctrl/pinmux.c b/drivers/pinctrl/pinmux.c
index 15ae972..680f690 100644
--- a/drivers/pinctrl/pinmux.c
+++ b/drivers/pinctrl/pinmux.c
@@ -21,6 +21,7 @@
#include <linux/list.h>
#include <linux/mutex.h>
#include <linux/spinlock.h>
+#include <linux/string.h>
#include <linux/sysfs.h>
#include <linux/debugfs.h>
#include <linux/seq_file.h>
@@ -37,7 +38,7 @@ static DEFINE_MUTEX(pinmux_hoglist_mutex);
static LIST_HEAD(pinmux_hoglist);
/* Global pinmux maps, we allow one set only */
-static struct pinmux_map const *pinmux_maps;
+static struct pinmux_map *pinmux_maps;
static unsigned pinmux_maps_num;
/**
@@ -337,7 +338,9 @@ EXPORT_SYMBOL_GPL(pinmux_gpio_direction_output);
/**
* pinmux_register_mappings() - register a set of pinmux mappings
- * @maps: the pinmux mappings table to register
+ * @maps: the pinmux mappings table to register, this should be marked with
+ * __initdata so it can be discarded after boot, this function will
+ * perform a shallow copy for the mapping entries.
* @num_maps: the number of maps in the mapping table
*
* Only call this once during initialization of your machine, the function is
@@ -348,32 +351,48 @@ EXPORT_SYMBOL_GPL(pinmux_gpio_direction_output);
int __init pinmux_register_mappings(struct pinmux_map const *maps,
unsigned num_maps)
{
+ int ret = 0;
int i;
- if (pinmux_maps != NULL) {
+ if (pinmux_maps_num != 0) {
pr_err("pinmux mappings already registered, you can only "
"register one set of maps\n");
return -EINVAL;
}
pr_debug("add %d pinmux maps\n", num_maps);
+
+ /*
+ * Make a copy of the map array - string pointers will end up in the
+ * kernel const section anyway so these do not need to be deep copied.
+ */
+ pinmux_maps = kmemdup(maps, sizeof(struct pinmux_map) * num_maps,
+ GFP_KERNEL);
+ if (!pinmux_maps)
+ return -ENOMEM;
+
for (i = 0; i < num_maps; i++) {
- /* Sanity check the mapping */
+ /* Sanity check the mapping while copying it */
if (!maps[i].name) {
pr_err("failed to register map %d: "
"no map name given\n", i);
- return -EINVAL;
+ ret = -EINVAL;
+ goto err_out_free;
}
+
if (!maps[i].ctrl_dev && !maps[i].ctrl_dev_name) {
pr_err("failed to register map %s (%d): "
"no pin control device given\n",
maps[i].name, i);
- return -EINVAL;
+ ret = -EINVAL;
+ goto err_out_free;
}
+
if (!maps[i].function) {
pr_err("failed to register map %s (%d): "
"no function ID given\n", maps[i].name, i);
- return -EINVAL;
+ ret = -EINVAL;
+ goto err_out_free;
}
if (!maps[i].dev && !maps[i].dev_name)
@@ -384,12 +403,17 @@ int __init pinmux_register_mappings(struct pinmux_map const *maps,
pr_debug("register map %s, function %s\n",
maps[i].name,
maps[i].function);
- }
- pinmux_maps = maps;
- pinmux_maps_num = num_maps;
+ pinmux_maps_num++;
+ }
return 0;
+
+err_out_free:
+ kfree(pinmux_maps);
+ pinmux_maps = NULL;
+ pinmux_maps_num = 0;
+ return ret;
}
/**
diff --git a/include/linux/pinctrl/machine.h b/include/linux/pinctrl/machine.h
index 8886353..f537231 100644
--- a/include/linux/pinctrl/machine.h
+++ b/include/linux/pinctrl/machine.h
@@ -48,7 +48,7 @@ struct pinmux_map {
const char *group;
struct device *dev;
const char *dev_name;
- const bool hog_on_boot;
+ bool hog_on_boot;
};
/*
--
1.7.3.2
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