4 files changed, 322 insertions, 113 deletions

diff --git a/drivers/clk/clk-fixed-factor.c b/drivers/clk/clk-fixed-factor.c
index 8aac2d1b6fea..8b343e59dc61 100644
--- a/drivers/clk/clk-fixed-factor.c
+++ b/drivers/clk/clk-fixed-factor.c
@@ -64,12 +64,14 @@ const struct clk_ops clk_fixed_factor_ops = {
 };
 EXPORT_SYMBOL_GPL(clk_fixed_factor_ops);
 
-struct clk_hw *clk_hw_register_fixed_factor(struct device *dev,
-                const char *name, const char *parent_name, unsigned long flags,
-                unsigned int mult, unsigned int div)
+static struct clk_hw *
+__clk_hw_register_fixed_factor(struct device *dev, struct device_node *np,
+                const char *name, const char *parent_name, int index,
+                unsigned long flags, unsigned int mult, unsigned int div)
 {
         struct clk_fixed_factor *fix;
-        struct clk_init_data init;
+        struct clk_init_data init = { };
+        struct clk_parent_data pdata = { .index = index };
         struct clk_hw *hw;
         int ret;
 
@@ -85,11 +87,17 @@ struct clk_hw *clk_hw_register_fixed_factor(struct device *dev,
         init.name = name;
         init.ops = &clk_fixed_factor_ops;
         init.flags = flags;
-        init.parent_names = &parent_name;
+        if (parent_name)
+                init.parent_names = &parent_name;
+        else
+                init.parent_data = &pdata;
         init.num_parents = 1;
 
         hw = &fix->hw;
-        ret = clk_hw_register(dev, hw);
+        if (dev)
+                ret = clk_hw_register(dev, hw);
+        else
+                ret = of_clk_hw_register(np, hw);
         if (ret) {
                 kfree(fix);
                 hw = ERR_PTR(ret);
@@ -97,6 +105,14 @@ struct clk_hw *clk_hw_register_fixed_factor(struct device *dev,
 
         return hw;
 }
+
+struct clk_hw *clk_hw_register_fixed_factor(struct device *dev,
+                const char *name, const char *parent_name, unsigned long flags,
+                unsigned int mult, unsigned int div)
+{
+        return __clk_hw_register_fixed_factor(dev, NULL, name, parent_name, -1,
+                                              flags, mult, div);
+}
 EXPORT_SYMBOL_GPL(clk_hw_register_fixed_factor);
 
 struct clk *clk_register_fixed_factor(struct device *dev, const char *name,
@@ -143,11 +159,10 @@ static const struct of_device_id set_rate_parent_matches[] = {
         { /* Sentinel */ },
 };
 
-static struct clk *_of_fixed_factor_clk_setup(struct device_node *node)
+static struct clk_hw *_of_fixed_factor_clk_setup(struct device_node *node)
 {
-        struct clk *clk;
+        struct clk_hw *hw;
         const char *clk_name = node->name;
-        const char *parent_name;
         unsigned long flags = 0;
         u32 div, mult;
         int ret;
@@ -165,30 +180,28 @@ static struct clk *_of_fixed_factor_clk_setup(struct device_node *node)
         }
 
         of_property_read_string(node, "clock-output-names", &clk_name);
-        parent_name = of_clk_get_parent_name(node, 0);
 
         if (of_match_node(set_rate_parent_matches, node))
                 flags |= CLK_SET_RATE_PARENT;
 
-        clk = clk_register_fixed_factor(NULL, clk_name, parent_name, flags,
-                                        mult, div);
-        if (IS_ERR(clk)) {
+        hw = __clk_hw_register_fixed_factor(NULL, node, clk_name, NULL, 0,
+                                            flags, mult, div);
+        if (IS_ERR(hw)) {
                 /*
-                 * If parent clock is not registered, registration would fail.
                  * Clear OF_POPULATED flag so that clock registration can be
                  * attempted again from probe function.
                  */
                 of_node_clear_flag(node, OF_POPULATED);
-                return clk;
+                return ERR_CAST(hw);
         }
 
-        ret = of_clk_add_provider(node, of_clk_src_simple_get, clk);
+        ret = of_clk_add_hw_provider(node, of_clk_hw_simple_get, hw);
         if (ret) {
-                clk_unregister(clk);
+                clk_hw_unregister_fixed_factor(hw);
                 return ERR_PTR(ret);
         }
 
-        return clk;
+        return hw;
 }
 
 /**
@@ -203,17 +216,17 @@ CLK_OF_DECLARE(fixed_factor_clk, "fixed-factor-clock",
 
 static int of_fixed_factor_clk_remove(struct platform_device *pdev)
 {
-        struct clk *clk = platform_get_drvdata(pdev);
+        struct clk_hw *clk = platform_get_drvdata(pdev);
 
         of_clk_del_provider(pdev->dev.of_node);
-        clk_unregister_fixed_factor(clk);
+        clk_hw_unregister_fixed_factor(clk);
 
         return 0;
 }
 
 static int of_fixed_factor_clk_probe(struct platform_device *pdev)
 {
-        struct clk *clk;
+        struct clk_hw *clk;
 
         /*
          * This function is not executed when of_fixed_factor_clk_setup
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 3e1708747cd2..aa51756fd4d6 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -39,15 +39,23 @@ static LIST_HEAD(clk_notifier_list);
 
 /***    private data structures    ***/
 
+struct clk_parent_map {
+        const struct clk_hw     *hw;
+        struct clk_core         *core;
+        const char              *fw_name;
+        const char              *name;
+        int                     index;
+};
+
 struct clk_core {
         const char              *name;
         const struct clk_ops    *ops;
         struct clk_hw           *hw;
         struct module           *owner;
         struct device           *dev;
+        struct device_node      *of_node;
         struct clk_core         *parent;
-        const char              **parent_names;
-        struct clk_core         **parents;
+        struct clk_parent_map   *parents;
         u8                      num_parents;
         u8                      new_parent_index;
         unsigned long           rate;
@@ -316,17 +324,102 @@ static struct clk_core *clk_core_lookup(const char *name)
         return NULL;
 }
 
+/**
+ * clk_core_get - Find the clk_core parent of a clk
+ * @core: clk to find parent of
+ * @p_index: parent index to search for
+ *
+ * This is the preferred method for clk providers to find the parent of a
+ * clk when that parent is external to the clk controller. The parent_names
+ * array is indexed and treated as a local name matching a string in the device
+ * node's 'clock-names' property or as the 'con_id' matching the device's
+ * dev_name() in a clk_lookup. This allows clk providers to use their own
+ * namespace instead of looking for a globally unique parent string.
+ *
+ * For example the following DT snippet would allow a clock registered by the
+ * clock-controller@c001 that has a clk_init_data::parent_data array
+ * with 'xtal' in the 'name' member to find the clock provided by the
+ * clock-controller@f00abcd without needing to get the globally unique name of
+ * the xtal clk.
+ *
+ *      parent: clock-controller@f00abcd {
+ *              reg = <0xf00abcd 0xabcd>;
+ *              #clock-cells = <0>;
+ *      };
+ *
+ *      clock-controller@c001 {
+ *              reg = <0xc001 0xf00d>;
+ *              clocks = <&parent>;
+ *              clock-names = "xtal";
+ *              #clock-cells = <1>;
+ *      };
+ *
+ * Returns: -ENOENT when the provider can't be found or the clk doesn't
+ * exist in the provider. -EINVAL when the name can't be found. NULL when the
+ * provider knows about the clk but it isn't provided on this system.
+ * A valid clk_core pointer when the clk can be found in the provider.
+ */
+static struct clk_core *clk_core_get(struct clk_core *core, u8 p_index)
+{
+        const char *name = core->parents[p_index].fw_name;
+        int index = core->parents[p_index].index;
+        struct clk_hw *hw = ERR_PTR(-ENOENT);
+        struct device *dev = core->dev;
+        const char *dev_id = dev ? dev_name(dev) : NULL;
+        struct device_node *np = core->of_node;
+
+        if (np && index >= 0)
+                hw = of_clk_get_hw(np, index, name);
+
+        /*
+         * If the DT search above couldn't find the provider or the provider
+         * didn't know about this clk, fallback to looking up via clkdev based
+         * clk_lookups
+         */
+        if (PTR_ERR(hw) == -ENOENT && name)
+                hw = clk_find_hw(dev_id, name);
+
+        if (IS_ERR(hw))
+                return ERR_CAST(hw);
+
+        return hw->core;
+}
+
+static void clk_core_fill_parent_index(struct clk_core *core, u8 index)
+{
+        struct clk_parent_map *entry = &core->parents[index];
+        struct clk_core *parent = ERR_PTR(-ENOENT);
+
+        if (entry->hw) {
+                parent = entry->hw->core;
+                /*
+                 * We have a direct reference but it isn't registered yet?
+                 * Orphan it and let clk_reparent() update the orphan status
+                 * when the parent is registered.
+                 */
+                if (!parent)
+                        parent = ERR_PTR(-EPROBE_DEFER);
+        } else {
+                parent = clk_core_get(core, index);
+                if (IS_ERR(parent) && PTR_ERR(parent) == -ENOENT)
+                        parent = clk_core_lookup(entry->name);
+        }
+
+        /* Only cache it if it's not an error */
+        if (!IS_ERR(parent))
+                entry->core = parent;
+}
+
 static struct clk_core *clk_core_get_parent_by_index(struct clk_core *core,
                                                          u8 index)
 {
-        if (!core || index >= core->num_parents)
+        if (!core || index >= core->num_parents || !core->parents)
                 return NULL;
 
-        if (!core->parents[index])
-                core->parents[index] =
-                                clk_core_lookup(core->parent_names[index]);
+        if (!core->parents[index].core)
+                clk_core_fill_parent_index(core, index);
 
-        return core->parents[index];
+        return core->parents[index].core;
 }
 
 struct clk_hw *
@@ -1520,20 +1613,37 @@ static int clk_fetch_parent_index(struct clk_core *core,
                 return -EINVAL;
 
         for (i = 0; i < core->num_parents; i++) {
-                if (core->parents[i] == parent)
+                /* Found it first try! */
+                if (core->parents[i].core == parent)
                         return i;
 
-                if (core->parents[i])
+                /* Something else is here, so keep looking */
+                if (core->parents[i].core)
                         continue;
 
-                /* Fallback to comparing globally unique names */
-                if (!strcmp(parent->name, core->parent_names[i])) {
-                        core->parents[i] = parent;
-                        return i;
+                /* Maybe core hasn't been cached but the hw is all we know? */
+                if (core->parents[i].hw) {
+                        if (core->parents[i].hw == parent->hw)
+                                break;
+
+                        /* Didn't match, but we're expecting a clk_hw */
+                        continue;
                 }
+
+                /* Maybe it hasn't been cached (clk_set_parent() path) */
+                if (parent == clk_core_get(core, i))
+                        break;
+
+                /* Fallback to comparing globally unique names */
+                if (!strcmp(parent->name, core->parents[i].name))
+                        break;
         }
 
-        return -EINVAL;
+        if (i == core->num_parents)
+                return -EINVAL;
+
+        core->parents[i].core = parent;
+        return i;
 }
 
 /*
@@ -2294,6 +2404,7 @@ void clk_hw_reparent(struct clk_hw *hw, struct clk_hw *new_parent)
 bool clk_has_parent(struct clk *clk, struct clk *parent)
 {
         struct clk_core *core, *parent_core;
+        int i;
 
         /* NULL clocks should be nops, so return success if either is NULL. */
         if (!clk || !parent)
@@ -2306,8 +2417,11 @@ bool clk_has_parent(struct clk *clk, struct clk *parent)
         if (core->parent == parent_core)
                 return true;
 
-        return match_string(core->parent_names, core->num_parents,
-                            parent_core->name) >= 0;
+        for (i = 0; i < core->num_parents; i++)
+                if (!strcmp(core->parents[i].name, parent_core->name))
+                        return true;
+
+        return false;
 }
 EXPORT_SYMBOL_GPL(clk_has_parent);
 
@@ -2889,9 +3003,9 @@ static int possible_parents_show(struct seq_file *s, void *data)
         int i;
 
         for (i = 0; i < core->num_parents - 1; i++)
-                seq_printf(s, "%s ", core->parent_names[i]);
+                seq_printf(s, "%s ", core->parents[i].name);
 
-        seq_printf(s, "%s\n", core->parent_names[i]);
+        seq_printf(s, "%s\n", core->parents[i].name);
 
         return 0;
 }
@@ -3025,7 +3139,7 @@ static inline void clk_debug_unregister(struct clk_core *core)
  */
 static int __clk_core_init(struct clk_core *core)
 {
-        int i, ret;
+        int ret;
         struct clk_core *orphan;
         struct hlist_node *tmp2;
         unsigned long rate;
@@ -3079,12 +3193,6 @@ static int __clk_core_init(struct clk_core *core)
                 goto out;
         }
 
-        /* throw a WARN if any entries in parent_names are NULL */
-        for (i = 0; i < core->num_parents; i++)
-                WARN(!core->parent_names[i],
-                                "%s: invalid NULL in %s's .parent_names\n",
-                                __func__, core->name);
-
         core->parent = __clk_init_parent(core);
 
         /*
@@ -3313,22 +3421,104 @@ struct clk *clk_hw_create_clk(struct device *dev, struct clk_hw *hw,
         return clk;
 }
 
-/**
- * clk_register - allocate a new clock, register it and return an opaque cookie
- * @dev: device that is registering this clock
- * @hw: link to hardware-specific clock data
- *
- * clk_register is the *deprecated* interface for populating the clock tree with
- * new clock nodes. Use clk_hw_register() instead.
- *
- * Returns: a pointer to the newly allocated struct clk which
- * cannot be dereferenced by driver code but may be used in conjunction with the
- * rest of the clock API.  In the event of an error clk_register will return an
- * error code; drivers must test for an error code after calling clk_register.
- */
-struct clk *clk_register(struct device *dev, struct clk_hw *hw)
+static int clk_cpy_name(const char **dst_p, const char *src, bool must_exist)
 {
-        int i, ret;
+        const char *dst;
+
+        if (!src) {
+                if (must_exist)
+                        return -EINVAL;
+                return 0;
+        }
+
+        *dst_p = dst = kstrdup_const(src, GFP_KERNEL);
+        if (!dst)
+                return -ENOMEM;
+
+        return 0;
+}
+
+static int clk_core_populate_parent_map(struct clk_core *core)
+{
+        const struct clk_init_data *init = core->hw->init;
+        u8 num_parents = init->num_parents;
+        const char * const *parent_names = init->parent_names;
+        const struct clk_hw **parent_hws = init->parent_hws;
+        const struct clk_parent_data *parent_data = init->parent_data;
+        int i, ret = 0;
+        struct clk_parent_map *parents, *parent;
+
+        if (!num_parents)
+                return 0;
+
+        /*
+         * Avoid unnecessary string look-ups of clk_core's possible parents by
+         * having a cache of names/clk_hw pointers to clk_core pointers.
+         */
+        parents = kcalloc(num_parents, sizeof(*parents), GFP_KERNEL);
+        core->parents = parents;
+        if (!parents)
+                return -ENOMEM;
+
+        /* Copy everything over because it might be __initdata */
+        for (i = 0, parent = parents; i < num_parents; i++, parent++) {
+                parent->index = -1;
+                if (parent_names) {
+                        /* throw a WARN if any entries are NULL */
+                        WARN(!parent_names[i],
+                                "%s: invalid NULL in %s's .parent_names\n",
+                                __func__, core->name);
+                        ret = clk_cpy_name(&parent->name, parent_names[i],
+                                           true);
+                } else if (parent_data) {
+                        parent->hw = parent_data[i].hw;
+                        parent->index = parent_data[i].index;
+                        ret = clk_cpy_name(&parent->fw_name,
+                                           parent_data[i].fw_name, false);
+                        if (!ret)
+                                ret = clk_cpy_name(&parent->name,
+                                                   parent_data[i].name,
+                                                   false);
+                } else if (parent_hws) {
+                        parent->hw = parent_hws[i];
+                } else {
+                        ret = -EINVAL;
+                        WARN(1, "Must specify parents if num_parents > 0\n");
+                }
+
+                if (ret) {
+                        do {
+                                kfree_const(parents[i].name);
+                                kfree_const(parents[i].fw_name);
+                        } while (--i >= 0);
+                        kfree(parents);
+
+                        return ret;
+                }
+        }
+
+        return 0;
+}
+
+static void clk_core_free_parent_map(struct clk_core *core)
+{
+        int i = core->num_parents;
+
+        if (!core->num_parents)
+                return;
+
+        while (--i >= 0) {
+                kfree_const(core->parents[i].name);
+                kfree_const(core->parents[i].fw_name);
+        }
+
+        kfree(core->parents);
+}
+
+static struct clk *
+__clk_register(struct device *dev, struct device_node *np, struct clk_hw *hw)
+{
+        int ret;
         struct clk_core *core;
 
         core = kzalloc(sizeof(*core), GFP_KERNEL);
@@ -3352,6 +3542,7 @@ struct clk *clk_register(struct device *dev, struct clk_hw *hw)
         if (dev && pm_runtime_enabled(dev))
                 core->rpm_enabled = true;
         core->dev = dev;
+        core->of_node = np;
         if (dev && dev->driver)
                 core->owner = dev->driver->owner;
         core->hw = hw;
@@ -3361,33 +3552,9 @@ struct clk *clk_register(struct device *dev, struct clk_hw *hw)
         core->max_rate = ULONG_MAX;
         hw->core = core;
 
-        /* allocate local copy in case parent_names is __initdata */
-        core->parent_names = kcalloc(core->num_parents, sizeof(char *),
-                                        GFP_KERNEL);
-
-        if (!core->parent_names) {
-                ret = -ENOMEM;
-                goto fail_parent_names;
-        }
-
-
-        /* copy each string name in case parent_names is __initdata */
-        for (i = 0; i < core->num_parents; i++) {
-                core->parent_names[i] = kstrdup_const(hw->init->parent_names[i],
-                                                GFP_KERNEL);
-                if (!core->parent_names[i]) {
-                        ret = -ENOMEM;
-                        goto fail_parent_names_copy;
-                }
-        }
-
-        /* avoid unnecessary string look-ups of clk_core's possible parents. */
-        core->parents = kcalloc(core->num_parents, sizeof(*core->parents),
-                                GFP_KERNEL);
-        if (!core->parents) {
-                ret = -ENOMEM;
+        ret = clk_core_populate_parent_map(core);
+        if (ret)
                 goto fail_parents;
-        };
 
         INIT_HLIST_HEAD(&core->clks);
 
@@ -3398,7 +3565,7 @@ struct clk *clk_register(struct device *dev, struct clk_hw *hw)
         hw->clk = alloc_clk(core, NULL, NULL);
         if (IS_ERR(hw->clk)) {
                 ret = PTR_ERR(hw->clk);
-                goto fail_parents;
+                goto fail_create_clk;
         }
 
         clk_core_link_consumer(hw->core, hw->clk);
@@ -3414,13 +3581,9 @@ struct clk *clk_register(struct device *dev, struct clk_hw *hw)
         free_clk(hw->clk);
         hw->clk = NULL;
 
+fail_create_clk:
+        clk_core_free_parent_map(core);
 fail_parents:
-        kfree(core->parents);
-fail_parent_names_copy:
-        while (--i >= 0)
-                kfree_const(core->parent_names[i]);
-        kfree(core->parent_names);
-fail_parent_names:
 fail_ops:
         kfree_const(core->name);
 fail_name:
@@ -3428,6 +3591,24 @@ fail_name:
 fail_out:
         return ERR_PTR(ret);
 }
+
+/**
+ * clk_register - allocate a new clock, register it and return an opaque cookie
+ * @dev: device that is registering this clock
+ * @hw: link to hardware-specific clock data
+ *
+ * clk_register is the *deprecated* interface for populating the clock tree with
+ * new clock nodes. Use clk_hw_register() instead.
+ *
+ * Returns: a pointer to the newly allocated struct clk which
+ * cannot be dereferenced by driver code but may be used in conjunction with the
+ * rest of the clock API.  In the event of an error clk_register will return an
+ * error code; drivers must test for an error code after calling clk_register.
+ */
+struct clk *clk_register(struct device *dev, struct clk_hw *hw)
+{
+        return __clk_register(dev, dev_of_node(dev), hw);
+}
 EXPORT_SYMBOL_GPL(clk_register);
 
 /**
@@ -3442,23 +3623,35 @@ EXPORT_SYMBOL_GPL(clk_register);
  */
 int clk_hw_register(struct device *dev, struct clk_hw *hw)
 {
-        return PTR_ERR_OR_ZERO(clk_register(dev, hw));
+        return PTR_ERR_OR_ZERO(__clk_register(dev, dev_of_node(dev), hw));
 }
 EXPORT_SYMBOL_GPL(clk_hw_register);
 
+/*
+ * of_clk_hw_register - register a clk_hw and return an error code
+ * @node: device_node of device that is registering this clock
+ * @hw: link to hardware-specific clock data
+ *
+ * of_clk_hw_register() is the primary interface for populating the clock tree
+ * with new clock nodes when a struct device is not available, but a struct
+ * device_node is. It returns an integer equal to zero indicating success or
+ * less than zero indicating failure. Drivers must test for an error code after
+ * calling of_clk_hw_register().
+ */
+int of_clk_hw_register(struct device_node *node, struct clk_hw *hw)
+{
+        return PTR_ERR_OR_ZERO(__clk_register(NULL, node, hw));
+}
+EXPORT_SYMBOL_GPL(of_clk_hw_register);
+
 /* Free memory allocated for a clock. */
 static void __clk_release(struct kref *ref)
 {
         struct clk_core *core = container_of(ref, struct clk_core, ref);
-        int i = core->num_parents;
 
         lockdep_assert_held(&prepare_lock);
 
-        kfree(core->parents);
-        while (--i >= 0)
-                kfree_const(core->parent_names[i]);
-
-        kfree(core->parent_names);
+        clk_core_free_parent_map(core);
         kfree_const(core->name);
         kfree(core);
 }
diff --git a/drivers/clk/clk.h b/drivers/clk/clk.h
index 553f531cc232..d8400d623b34 100644
--- a/drivers/clk/clk.h
+++ b/drivers/clk/clk.h
@@ -19,6 +19,8 @@ static inline struct clk_hw *of_clk_get_hw(struct device_node *np,
 }
 #endif
 
+struct clk_hw *clk_find_hw(const char *dev_id, const char *con_id);
+
 #ifdef CONFIG_COMMON_CLK
 struct clk *clk_hw_create_clk(struct device *dev, struct clk_hw *hw,
                               const char *dev_id, const char *con_id);
diff --git a/drivers/clk/clkdev.c b/drivers/clk/clkdev.c
index 6e787cc9e5b9..2afc8df8acff 100644
--- a/drivers/clk/clkdev.c
+++ b/drivers/clk/clkdev.c
@@ -72,25 +72,26 @@ static struct clk_lookup *clk_find(const char *dev_id, const char *con_id)
         return cl;
 }
 
-static struct clk *__clk_get_sys(struct device *dev, const char *dev_id,
-                                 const char *con_id)
+struct clk_hw *clk_find_hw(const char *dev_id, const char *con_id)
 {
         struct clk_lookup *cl;
-        struct clk *clk = NULL;
+        struct clk_hw *hw = ERR_PTR(-ENOENT);
 
         mutex_lock(&clocks_mutex);
-
         cl = clk_find(dev_id, con_id);
-        if (!cl)
-                goto out;
-
-        clk = clk_hw_create_clk(dev, cl->clk_hw, dev_id, con_id);
-        if (IS_ERR(clk))
-                cl = NULL;
-out:
+        if (cl)
+                hw = cl->clk_hw;
         mutex_unlock(&clocks_mutex);
 
-        return cl ? clk : ERR_PTR(-ENOENT);
+        return hw;
+}
+
+static struct clk *__clk_get_sys(struct device *dev, const char *dev_id,
+                                 const char *con_id)
+{
+        struct clk_hw *hw = clk_find_hw(dev_id, con_id);
+
+        return clk_hw_create_clk(dev, hw, dev_id, con_id);
 }
 
 struct clk *clk_get_sys(const char *dev_id, const char *con_id)