PM / OPP: Manage device clk

OPP core has got almost everything now to manage device's OPP
transitions, the only thing left is device's clk. Get that as well.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

2 files changed, 18 insertions, 0 deletions

diff --git a/drivers/base/power/opp/core.c b/drivers/base/power/opp/core.c
index 4fafa733a1c7..7d7749ce1ce4 100644
--- a/drivers/base/power/opp/core.c
+++ b/drivers/base/power/opp/core.c
@@ -13,6 +13,7 @@
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
+#include <linux/clk.h>
 #include <linux/errno.h>
 #include <linux/err.h>
 #include <linux/slab.h>
@@ -583,6 +584,7 @@ static struct device_opp *_add_device_opp(struct device *dev)
         struct device_opp *dev_opp;
         struct device_list_opp *list_dev;
         struct device_node *np;
+        int ret;
 
         /* Check for existing list for 'dev' first */
         dev_opp = _find_device_opp(dev);
@@ -620,6 +622,15 @@ static struct device_opp *_add_device_opp(struct device *dev)
                 of_node_put(np);
         }
 
+        /* Find clk for the device */
+        dev_opp->clk = clk_get(dev, NULL);
+        if (IS_ERR(dev_opp->clk)) {
+                ret = PTR_ERR(dev_opp->clk);
+                if (ret != -EPROBE_DEFER)
+                        dev_dbg(dev, "%s: Couldn't find clock: %d\n", __func__,
+                                ret);
+        }
+
         srcu_init_notifier_head(&dev_opp->srcu_head);
         INIT_LIST_HEAD(&dev_opp->opp_list);
 
@@ -661,6 +672,10 @@ static void _remove_device_opp(struct device_opp *dev_opp)
         if (!IS_ERR_OR_NULL(dev_opp->regulator))
                 return;
 
+        /* Release clk */
+        if (!IS_ERR(dev_opp->clk))
+                clk_put(dev_opp->clk);
+
         list_dev = list_first_entry(&dev_opp->dev_list, struct device_list_opp,
                                     node);
 
diff --git a/drivers/base/power/opp/opp.h b/drivers/base/power/opp/opp.h
index fe44beb404ba..4f1bdfc7da03 100644
--- a/drivers/base/power/opp/opp.h
+++ b/drivers/base/power/opp/opp.h
@@ -22,6 +22,7 @@
 #include <linux/rculist.h>
 #include <linux/rcupdate.h>
 
+struct clk;
 struct regulator;
 
 /* Lock to allow exclusive modification to the device and opp lists */
@@ -134,6 +135,7 @@ struct device_list_opp {
  * @supported_hw: Array of version number to support.
  * @supported_hw_count: Number of elements in supported_hw array.
  * @prop_name: A name to postfix to many DT properties, while parsing them.
+ * @clk: Device's clock handle
  * @regulator: Supply regulator
  * @dentry:     debugfs dentry pointer of the real device directory (not links).
  * @dentry_name: Name of the real dentry.
@@ -168,6 +170,7 @@ struct device_opp {
         unsigned int *supported_hw;
         unsigned int supported_hw_count;
         const char *prop_name;
+        struct clk *clk;
         struct regulator *regulator;
 
 #ifdef CONFIG_DEBUG_FS