6 files changed, 65 insertions, 14 deletions

diff --git a/arch/arm/mach-omap2/omap_hwmod.c b/arch/arm/mach-omap2/omap_hwmod.c
index 03ffa3b282b1..77a8be64cfae 100644
--- a/arch/arm/mach-omap2/omap_hwmod.c
+++ b/arch/arm/mach-omap2/omap_hwmod.c
@@ -2188,3 +2188,25 @@ ohsps_unlock:
 
         return ret;
 }
+
+/**
+ * omap_hwmod_get_context_loss_count - get lost context count
+ * @oh: struct omap_hwmod *
+ *
+ * Query the powerdomain of of @oh to get the context loss
+ * count for this device.
+ *
+ * Returns the context loss count of the powerdomain assocated with @oh
+ * upon success, or zero if no powerdomain exists for @oh.
+ */
+u32 omap_hwmod_get_context_loss_count(struct omap_hwmod *oh)
+{
+        struct powerdomain *pwrdm;
+        int ret = 0;
+
+        pwrdm = omap_hwmod_get_pwrdm(oh);
+        if (pwrdm)
+                ret = pwrdm_get_context_loss_count(pwrdm);
+
+        return ret;
+}
diff --git a/arch/arm/plat-omap/include/plat/omap-pm.h b/arch/arm/plat-omap/include/plat/omap-pm.h
index 47d61107ccda..c07bb44e9e5a 100644
--- a/arch/arm/plat-omap/include/plat/omap-pm.h
+++ b/arch/arm/plat-omap/include/plat/omap-pm.h
@@ -350,9 +350,9 @@ unsigned long omap_pm_cpu_get_freq(void);
  * driver must restore device context.   If the number of context losses
  * exceeds the maximum positive integer, the function will wrap to 0 and
  * continue counting.  Returns the number of context losses for this device,
- * or -EINVAL upon error.
+ * or zero upon error.
  */
-int omap_pm_get_dev_context_loss_count(struct device *dev);
+u32 omap_pm_get_dev_context_loss_count(struct device *dev);
 
 
 #endif
diff --git a/arch/arm/plat-omap/include/plat/omap_device.h b/arch/arm/plat-omap/include/plat/omap_device.h
index 28e2d1a78433..e4c349ff9fd8 100644
--- a/arch/arm/plat-omap/include/plat/omap_device.h
+++ b/arch/arm/plat-omap/include/plat/omap_device.h
@@ -107,6 +107,7 @@ void __iomem *omap_device_get_rt_va(struct omap_device *od);
 int omap_device_align_pm_lat(struct platform_device *pdev,
                              u32 new_wakeup_lat_limit);
 struct powerdomain *omap_device_get_pwrdm(struct omap_device *od);
+u32 omap_device_get_context_loss_count(struct platform_device *pdev);
 
 /* Other */
 
diff --git a/arch/arm/plat-omap/include/plat/omap_hwmod.h b/arch/arm/plat-omap/include/plat/omap_hwmod.h
index 619877c6b3ab..2825b456da0e 100644
--- a/arch/arm/plat-omap/include/plat/omap_hwmod.h
+++ b/arch/arm/plat-omap/include/plat/omap_hwmod.h
@@ -569,6 +569,7 @@ int omap_hwmod_for_each_by_class(const char *classname,
                                  void *user);
 
 int omap_hwmod_set_postsetup_state(struct omap_hwmod *oh, u8 state);
+u32 omap_hwmod_get_context_loss_count(struct omap_hwmod *oh);
 
 /*
  * Chip variant-specific hwmod init routines - XXX should be converted
diff --git a/arch/arm/plat-omap/omap-pm-noop.c b/arch/arm/plat-omap/omap-pm-noop.c
index 19cb9f5a9f04..af58daddcf50 100644
--- a/arch/arm/plat-omap/omap-pm-noop.c
+++ b/arch/arm/plat-omap/omap-pm-noop.c
@@ -20,9 +20,11 @@
 #include <linux/init.h>
 #include <linux/cpufreq.h>
 #include <linux/device.h>
+#include <linux/platform_device.h>
 
 /* Interface documentation is in mach/omap-pm.h */
 #include <plat/omap-pm.h>
+#include <plat/omap_device.h>
 
 /*
  * Device-driver-originated constraints (via board-*.c files)
@@ -282,22 +284,19 @@ unsigned long omap_pm_cpu_get_freq(void)
  * Device context loss tracking
  */
 
-int omap_pm_get_dev_context_loss_count(struct device *dev)
+u32 omap_pm_get_dev_context_loss_count(struct device *dev)
 {
-        if (!dev) {
-                WARN_ON(1);
-                return -EINVAL;
-        };
+        struct platform_device *pdev = to_platform_device(dev);
+        u32 count;
 
-        pr_debug("OMAP PM: returning context loss count for dev %s\n",
-                 dev_name(dev));
+        if (WARN_ON(!dev))
+                return 0;
 
-        /*
-         * Map the device to the powerdomain.  Return the powerdomain
-         * off counter.
-         */
+        count = omap_device_get_context_loss_count(pdev);
+        pr_debug("OMAP PM: context loss count for dev %s = %d\n",
+                 dev_name(dev), count);
 
-        return 0;
+        return count;
 }
 
 
diff --git a/arch/arm/plat-omap/omap_device.c b/arch/arm/plat-omap/omap_device.c
index abe933cd8f09..57adb270767b 100644
--- a/arch/arm/plat-omap/omap_device.c
+++ b/arch/arm/plat-omap/omap_device.c
@@ -280,6 +280,34 @@ static void _add_optional_clock_alias(struct omap_device *od,
 /* Public functions for use by core code */
 
 /**
+ * omap_device_get_context_loss_count - get lost context count
+ * @od: struct omap_device *
+ *
+ * Using the primary hwmod, query the context loss count for this
+ * device.
+ *
+ * Callers should consider context for this device lost any time this
+ * function returns a value different than the value the caller got
+ * the last time it called this function.
+ *
+ * If any hwmods exist for the omap_device assoiated with @pdev,
+ * return the context loss counter for that hwmod, otherwise return
+ * zero.
+ */
+u32 omap_device_get_context_loss_count(struct platform_device *pdev)
+{
+        struct omap_device *od;
+        u32 ret = 0;
+
+        od = _find_by_pdev(pdev);
+
+        if (od->hwmods_cnt)
+                ret = omap_hwmod_get_context_loss_count(od->hwmods[0]);
+
+        return ret;
+}
+
+/**
  * omap_device_count_resources - count number of struct resource entries needed
  * @od: struct omap_device *
  *