[ARM] S3C: Do not kmalloc/kfree during inner suspend code.

The PM CRC checking code kmallocs an area to save a set of
CRC values during suspend. This triggers a warning due to the
call of a function that might sleep whilst the system is not
in a valid state to do so.

Move the allocation and free to points in the suspend and resume
process where they can call a function that might-sleep.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>

3 files changed, 33 insertions, 8 deletions

diff --git a/arch/arm/plat-s3c/include/plat/pm.h b/arch/arm/plat-s3c/include/plat/pm.h
index c27b8cf5d891..5ee26da27028 100644
--- a/arch/arm/plat-s3c/include/plat/pm.h
+++ b/arch/arm/plat-s3c/include/plat/pm.h
@@ -129,10 +129,12 @@ extern void s3c_pm_dbg(const char *msg, ...);
 #ifdef CONFIG_S3C2410_PM_CHECK
 extern void s3c_pm_check_prepare(void);
 extern void s3c_pm_check_restore(void);
+extern void s3c_pm_check_cleanup(void);
 extern void s3c_pm_check_store(void);
 #else
 #define s3c_pm_check_prepare() do { } while(0)
 #define s3c_pm_check_restore() do { } while(0)
+#define s3c_pm_check_cleanup() do { } while(0)
 #define s3c_pm_check_store()   do { } while(0)
 #endif
 
diff --git a/arch/arm/plat-s3c/pm-check.c b/arch/arm/plat-s3c/pm-check.c
index 183f1304bf58..39f2555564da 100644
--- a/arch/arm/plat-s3c/pm-check.c
+++ b/arch/arm/plat-s3c/pm-check.c
@@ -222,9 +222,21 @@ static u32 *s3c_pm_runcheck(struct resource *res, u32 *val)
 */
 void s3c_pm_check_restore(void)
 {
-        if (crcs != NULL) {
+        if (crcs != NULL)
                 s3c_pm_run_sysram(s3c_pm_runcheck, crcs);
-                kfree(crcs);
-                crcs = NULL;
-        }
 }
+
+/**
+ * s3c_pm_check_cleanup() - free memory resources
+ *
+ * Free the resources that where allocated by the suspend
+ * memory check code. We do this separately from the
+ * s3c_pm_check_restore() function as we cannot call any
+ * functions that might sleep during that resume.
+ */
+void s3c_pm_check_cleanup(void)
+{
+        kfree(crcs);
+        crcs = NULL;
+}
+
diff --git a/arch/arm/plat-s3c/pm.c b/arch/arm/plat-s3c/pm.c
index 78bf50a14027..a0ca18a75b0e 100644
--- a/arch/arm/plat-s3c/pm.c
+++ b/arch/arm/plat-s3c/pm.c
@@ -254,10 +254,6 @@ static int s3c_pm_enter(suspend_state_t state)
                 return -EINVAL;
         }
 
-        /* prepare check area if configured */
-
-        s3c_pm_check_prepare();
-
         /* store the physical address of the register recovery block */
 
         s3c_sleep_save_phys = virt_to_phys(regs_save);
@@ -329,8 +325,23 @@ static int s3c_pm_enter(suspend_state_t state)
         return 0;
 }
 
+static int s3c_pm_prepare(void)
+{
+        /* prepare check area if configured */
+
+        s3c_pm_check_prepare();
+        return 0;
+}
+
+static void s3c_pm_finish(void)
+{
+        s3c_pm_check_cleanup();
+}
+
 static struct platform_suspend_ops s3c_pm_ops = {
         .enter          = s3c_pm_enter,
+        .prepare        = s3c_pm_prepare,
+        .finish         = s3c_pm_finish,
         .valid          = suspend_valid_only_mem,
 };