OMAP clockdomain/powerdomain: remove runtime register/unregister

OMAP clockdomains and powerdomains are currently defined statically,
only registered at boot, and never unregistered, so we can remove the
unregister function and the locking.   A variant of this was originally
suggested a while ago by Dmitry Baryshkov <dbaryshkov@gmail.com>.
This version of this patch contains an additional fix from Kevin Hilman
<khilman@deeprootsystems.com> to address one of the pwrdm_for_each_nolock()
users in mach-omap2/pm-debug.c.   Thanks Kevin.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Dmitry Baryshkov <dbaryshkov@gmail.com>
Cc: Kevin Hilman <khilman@deeprootsystems.com>

1 files changed, 40 insertions, 78 deletions

diff --git a/arch/arm/mach-omap2/clockdomain.c b/arch/arm/mach-omap2/clockdomain.c
index a70ba29f66cc..2af9996f010b 100644
--- a/arch/arm/mach-omap2/clockdomain.c
+++ b/arch/arm/mach-omap2/clockdomain.c
@@ -39,9 +39,6 @@
 /* clkdm_list contains all registered struct clockdomains */
 static LIST_HEAD(clkdm_list);
 
-/* clkdm_mutex protects clkdm_list add and del ops */
-static DEFINE_MUTEX(clkdm_mutex);
-
 /* array of clockdomain deps to be added/removed when clkdm in hwsup mode */
 static struct clkdm_autodep *autodeps;
 
@@ -67,6 +64,45 @@ static struct clockdomain *_clkdm_lookup(const char *name)
         return clkdm;
 }
 
+/**
+ * _clkdm_register - register a clockdomain
+ * @clkdm: struct clockdomain * to register
+ *
+ * Adds a clockdomain to the internal clockdomain list.
+ * Returns -EINVAL if given a null pointer, -EEXIST if a clockdomain is
+ * already registered by the provided name, or 0 upon success.
+ */
+static int _clkdm_register(struct clockdomain *clkdm)
+{
+        struct powerdomain *pwrdm;
+
+        if (!clkdm || !clkdm->name)
+                return -EINVAL;
+
+        if (!omap_chip_is(clkdm->omap_chip))
+                return -EINVAL;
+
+        pwrdm = pwrdm_lookup(clkdm->pwrdm.name);
+        if (!pwrdm) {
+                pr_err("clockdomain: %s: powerdomain %s does not exist\n",
+                        clkdm->name, clkdm->pwrdm.name);
+                return -EINVAL;
+        }
+        clkdm->pwrdm.ptr = pwrdm;
+
+        /* Verify that the clockdomain is not already registered */
+        if (_clkdm_lookup(clkdm->name))
+                return -EEXIST;
+
+        list_add(&clkdm->node, &clkdm_list);
+
+        pwrdm_add_clkdm(pwrdm, clkdm);
+
+        pr_debug("clockdomain: registered %s\n", clkdm->name);
+
+        return 0;
+}
+
 /* _clkdm_deps_lookup - look up the specified clockdomain in a clkdm list */
 static struct clkdm_dep *_clkdm_deps_lookup(struct clockdomain *clkdm,
                                             struct clkdm_dep *deps)
@@ -240,7 +276,7 @@ void clkdm_init(struct clockdomain **clkdms,
 
         if (clkdms)
                 for (c = clkdms; *c; c++)
-                        clkdm_register(*c);
+                        _clkdm_register(*c);
 
         autodeps = init_autodeps;
         if (autodeps)
@@ -249,76 +285,6 @@ void clkdm_init(struct clockdomain **clkdms,
 }
 
 /**
- * clkdm_register - register a clockdomain
- * @clkdm: struct clockdomain * to register
- *
- * Adds a clockdomain to the internal clockdomain list.
- * Returns -EINVAL if given a null pointer, -EEXIST if a clockdomain is
- * already registered by the provided name, or 0 upon success.
- */
-int clkdm_register(struct clockdomain *clkdm)
-{
-        int ret = -EINVAL;
-        struct powerdomain *pwrdm;
-
-        if (!clkdm || !clkdm->name)
-                return -EINVAL;
-
-        if (!omap_chip_is(clkdm->omap_chip))
-                return -EINVAL;
-
-        pwrdm = pwrdm_lookup(clkdm->pwrdm.name);
-        if (!pwrdm) {
-                pr_err("clockdomain: %s: powerdomain %s does not exist\n",
-                        clkdm->name, clkdm->pwrdm.name);
-                return -EINVAL;
-        }
-        clkdm->pwrdm.ptr = pwrdm;
-
-        mutex_lock(&clkdm_mutex);
-        /* Verify that the clockdomain is not already registered */
-        if (_clkdm_lookup(clkdm->name)) {
-                ret = -EEXIST;
-                goto cr_unlock;
-        }
-
-        list_add(&clkdm->node, &clkdm_list);
-
-        pwrdm_add_clkdm(pwrdm, clkdm);
-
-        pr_debug("clockdomain: registered %s\n", clkdm->name);
-        ret = 0;
-
-cr_unlock:
-        mutex_unlock(&clkdm_mutex);
-
-        return ret;
-}
-
-/**
- * clkdm_unregister - unregister a clockdomain
- * @clkdm: struct clockdomain * to unregister
- *
- * Removes a clockdomain from the internal clockdomain list.  Returns
- * -EINVAL if clkdm argument is NULL.
- */
-int clkdm_unregister(struct clockdomain *clkdm)
-{
-        if (!clkdm)
-                return -EINVAL;
-
-        pwrdm_del_clkdm(clkdm->pwrdm.ptr, clkdm);
-
-        mutex_lock(&clkdm_mutex);
-        list_del(&clkdm->node);
-        mutex_unlock(&clkdm_mutex);
-
-        pr_debug("clockdomain: unregistered %s\n", clkdm->name);
-
-        return 0;
-}
-
-/**
  * clkdm_lookup - look up a clockdomain by name, return a pointer
  * @name: name of clockdomain
  *
@@ -334,14 +300,12 @@ struct clockdomain *clkdm_lookup(const char *name)
 
         clkdm = NULL;
 
-        mutex_lock(&clkdm_mutex);
         list_for_each_entry(temp_clkdm, &clkdm_list, node) {
                 if (!strcmp(name, temp_clkdm->name)) {
                         clkdm = temp_clkdm;
                         break;
                 }
         }
-        mutex_unlock(&clkdm_mutex);
 
         return clkdm;
 }
@@ -369,13 +333,11 @@ int clkdm_for_each(int (*fn)(struct clockdomain *clkdm, void *user),
         if (!fn)
                 return -EINVAL;
 
-        mutex_lock(&clkdm_mutex);
         list_for_each_entry(clkdm, &clkdm_list, node) {
                 ret = (*fn)(clkdm, user);
                 if (ret)
                         break;
         }
-        mutex_unlock(&clkdm_mutex);
 
         return ret;
 }