summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorDavid S. Miller <davem@davemloft.net>2008-08-19 21:56:35 -0700
committerDavid S. Miller <davem@davemloft.net>2008-08-24 20:33:55 -0700
commit2481d76615d5e15340ccfb0243fe8779766dfc6e (patch)
tree2d047756426224d741388b4c557151f9a7cb8335
parent072bd413b88c17509c7aa7dbc398ab8bade633b3 (diff)
downloadop-kernel-dev-2481d76615d5e15340ccfb0243fe8779766dfc6e.zip
op-kernel-dev-2481d76615d5e15340ccfb0243fe8779766dfc6e.tar.gz
sparc: Add mutex for set property calls.
On some platforms, the I2C controller is shared between the OS and OBP. OBP uses this I2C controller to access the EEPROM, and thus is programmed when the kernel calls prom_setprop(). Wrap such calls with the new of_set_property_mutex. Relevant I2C bus drivers can grab this mutex around top-level I2C operations to provide the proper protection. Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r--arch/sparc/include/asm/prom.h2
-rw-r--r--arch/sparc/kernel/prom.c6
-rw-r--r--arch/sparc64/kernel/prom.c6
3 files changed, 14 insertions, 0 deletions
diff --git a/arch/sparc/include/asm/prom.h b/arch/sparc/include/asm/prom.h
index fd55522..b5efc4d 100644
--- a/arch/sparc/include/asm/prom.h
+++ b/arch/sparc/include/asm/prom.h
@@ -18,6 +18,7 @@
*/
#include <linux/types.h>
#include <linux/proc_fs.h>
+#include <linux/mutex.h>
#include <asm/atomic.h>
#define OF_ROOT_NODE_ADDR_CELLS_DEFAULT 2
@@ -73,6 +74,7 @@ struct of_irq_controller {
extern struct device_node *of_find_node_by_cpuid(int cpuid);
extern int of_set_property(struct device_node *node, const char *name, void *val, int len);
+extern struct mutex of_set_property_mutex;
extern int of_getintprop_default(struct device_node *np,
const char *name,
int def);
diff --git a/arch/sparc/kernel/prom.c b/arch/sparc/kernel/prom.c
index cd4fb79a..43e8624 100644
--- a/arch/sparc/kernel/prom.c
+++ b/arch/sparc/kernel/prom.c
@@ -54,6 +54,9 @@ int of_getintprop_default(struct device_node *np, const char *name, int def)
}
EXPORT_SYMBOL(of_getintprop_default);
+DEFINE_MUTEX(of_set_property_mutex);
+EXPORT_SYMBOL(of_set_property_mutex);
+
int of_set_property(struct device_node *dp, const char *name, void *val, int len)
{
struct property **prevp;
@@ -77,7 +80,10 @@ int of_set_property(struct device_node *dp, const char *name, void *val, int len
void *old_val = prop->value;
int ret;
+ mutex_lock(&of_set_property_mutex);
ret = prom_setprop(dp->node, (char *) name, val, len);
+ mutex_unlock(&of_set_property_mutex);
+
err = -EINVAL;
if (ret >= 0) {
prop->value = new_val;
diff --git a/arch/sparc64/kernel/prom.c b/arch/sparc64/kernel/prom.c
index 3c048ac..922dd61 100644
--- a/arch/sparc64/kernel/prom.c
+++ b/arch/sparc64/kernel/prom.c
@@ -59,6 +59,9 @@ int of_getintprop_default(struct device_node *np, const char *name, int def)
}
EXPORT_SYMBOL(of_getintprop_default);
+DEFINE_MUTEX(of_set_property_mutex);
+EXPORT_SYMBOL(of_set_property_mutex);
+
int of_set_property(struct device_node *dp, const char *name, void *val, int len)
{
struct property **prevp;
@@ -82,7 +85,10 @@ int of_set_property(struct device_node *dp, const char *name, void *val, int len
void *old_val = prop->value;
int ret;
+ mutex_lock(&of_set_property_mutex);
ret = prom_setprop(dp->node, name, val, len);
+ mutex_unlock(&of_set_property_mutex);
+
err = -EINVAL;
if (ret >= 0) {
prop->value = new_val;
OpenPOWER on IntegriCloud