[PATCH v2 03/13] clk: Add clk_hw OF clk providers

Stephen Boyd
2016-04-21T22:22:13Z

Now that we have a clk registration API that doesn't return
struct clks, we need to have some way to hand out struct clks via
the clk_get() APIs that doesn't involve associating struct clk
pointers with an OF node. Currently we ask the OF provider to
give us a struct clk pointer for some clkspec, turn that struct
clk into a struct clk_hw and then allocate a new struct clk to
return to the caller.

Let's add a clk_hw based OF provider hook that returns a struct
clk_hw directly, so that we skip the intermediate step of
converting from struct clk to struct clk_hw. Eventually when
we've converted all OF clk providers to struct clk_hw based APIs
we can remove the struct clk based ones.

It should also be noted that we change the onecell provider to
have a flex array instead of a pointer for the array of clk_hw
pointers. This allows providers to allocate one structure of the
correct length in one step instead of two.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
---
drivers/clk/clk.c | 85 +++++++++++++++++++++++++++++++++++++++++---
include/linux/clk-provider.h | 30 ++++++++++++++++
2 files changed, 111 insertions(+), 4 deletions(-)

diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 0ef919666827..e813b2aabc87 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -2941,6 +2941,7 @@ struct of_clk_provider {

struct device_node *node;
struct clk *(*get)(struct of_phandle_args *clkspec, void *data);
+ struct clk_hw *(*get_hw)(struct of_phandle_args *clkspec, void *data);
void *data;
};

@@ -2957,6 +2958,12 @@ struct clk *of_clk_src_simple_get(struct of_phandle_args *clkspec,
}
EXPORT_SYMBOL_GPL(of_clk_src_simple_get);

+struct clk_hw *of_clk_hw_simple_get(struct of_phandle_args *clkspec, void *data)
+{
+ return data;
+}
+EXPORT_SYMBOL_GPL(of_clk_hw_simple_get);
+
struct clk *of_clk_src_onecell_get(struct of_phandle_args *clkspec, void *data)
{
struct clk_onecell_data *clk_data = data;
@@ -2971,6 +2978,21 @@ struct clk *of_clk_src_onecell_get(struct of_phandle_args *clkspec, void *data)
}
EXPORT_SYMBOL_GPL(of_clk_src_onecell_get);

+struct clk_hw *
+of_clk_hw_onecell_get(struct of_phandle_args *clkspec, void *data)
+{
+ struct clk_hw_onecell_data *hw_data = data;
+ unsigned int idx = clkspec->args[0];
+
+ if (idx >= hw_data->num) {
+ pr_err("%s: invalid index %u\n", __func__, idx);
+ return ERR_PTR(-EINVAL);
+ }
+
+ return hw_data->hws[idx];
+}
+EXPORT_SYMBOL_GPL(of_clk_hw_onecell_get);
+
/**
* of_clk_add_provider() - Register a clock provider for a node
* @np: Device node pointer associated with clock provider
@@ -3007,6 +3029,41 @@ int of_clk_add_provider(struct device_node *np,
EXPORT_SYMBOL_GPL(of_clk_add_provider);

/**
+ * of_clk_add_hw_provider() - Register a clock provider for a node
+ * @np: Device node pointer associated with clock provider
+ * @get: callback for decoding clk_hw
+ * @data: context pointer for @get callback.
+ */
+int of_clk_add_hw_provider(struct device_node *np,
+ struct clk_hw *(*get)(struct of_phandle_args *clkspec,
+ void *data),
+ void *data)
+{
+ struct of_clk_provider *cp;
+ int ret;
+
+ cp = kzalloc(sizeof(*cp), GFP_KERNEL);
+ if (!cp)
+ return -ENOMEM;
+
+ cp->node = of_node_get(np);
+ cp->data = data;
+ cp->get_hw = get;
+
+ mutex_lock(&of_clk_mutex);
+ list_add(&cp->link, &of_clk_providers);
+ mutex_unlock(&of_clk_mutex);
+ pr_debug("Added clk_hw provider from %s\n", np->full_name);
+
+ ret = of_clk_set_defaults(np, true);
+ if (ret < 0)
+ of_clk_del_provider(np);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(of_clk_add_hw_provider);
+
+/**
* of_clk_del_provider() - Remove a previously registered clock provider
* @np: Device node pointer associated with clock provider
*/
@@ -3027,11 +3084,32 @@ void of_clk_del_provider(struct device_node *np)
}
EXPORT_SYMBOL_GPL(of_clk_del_provider);

+static struct clk_hw *
+__of_clk_get_hw_from_provider(struct of_clk_provider *provider,
+ struct of_phandle_args *clkspec)
+{
+ struct clk *clk;
+ struct clk_hw *hw = ERR_PTR(-EPROBE_DEFER);
+
+ if (provider->get_hw) {
+ hw = provider->get_hw(clkspec, provider->data);
+ } else if (provider->get) {
+ clk = provider->get(clkspec, provider->data);
+ if (!IS_ERR(clk))
+ hw = __clk_get_hw(clk);
+ else
+ hw = ERR_CAST(clk);
+ }
+
+ return hw;
+}
+
struct clk *__of_clk_get_from_provider(struct of_phandle_args *clkspec,
const char *dev_id, const char *con_id)
{
struct of_clk_provider *provider;
struct clk *clk = ERR_PTR(-EPROBE_DEFER);
+ struct clk_hw *hw = ERR_PTR(-EPROBE_DEFER);

if (!clkspec)
return ERR_PTR(-EINVAL);
@@ -3040,10 +3118,9 @@ struct clk *__of_clk_get_from_provider(struct of_phandle_args *clkspec,
mutex_lock(&of_clk_mutex);
list_for_each_entry(provider, &of_clk_providers, link) {
if (provider->node == clkspec->np)
- clk = provider->get(clkspec, provider->data);
- if (!IS_ERR(clk)) {
- clk = __clk_create_clk(__clk_get_hw(clk), dev_id,
- con_id);
+ hw = __of_clk_get_hw_from_provider(provider, clkspec);
+ if (!IS_ERR(hw)) {
+ clk = __clk_create_clk(hw, dev_id, con_id);

if (!IS_ERR(clk) && !__clk_get(clk)) {
__clk_free_clk(clk);
diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h
index bc6c8de1fac1..bf8c8bb8c2cb 100644
--- a/include/linux/clk-provider.h
+++ b/include/linux/clk-provider.h
@@ -709,6 +709,11 @@ struct clk_onecell_data {
unsigned int clk_num;
};

+struct clk_hw_onecell_data {
+ size_t num;
+ struct clk_hw *hws[];
+};
+
extern struct of_device_id __clk_of_table;

#define CLK_OF_DECLARE(name, compat, fn) OF_DECLARE_1(clk, name, compat, fn)
@@ -718,10 +723,18 @@ int of_clk_add_provider(struct device_node *np,
struct clk *(*clk_src_get)(struct of_phandle_args *args,
void *data),
void *data);
+int of_clk_add_hw_provider(struct device_node *np,
+ struct clk_hw *(*get)(struct of_phandle_args *clkspec,
+ void *data),
+ void *data);
void of_clk_del_provider(struct device_node *np);
struct clk *of_clk_src_simple_get(struct of_phandle_args *clkspec,
void *data);
+struct clk_hw *of_clk_hw_simple_get(struct of_phandle_args *clkspec,
+ void *data);
struct clk *of_clk_src_onecell_get(struct of_phandle_args *clkspec, void *data);
+struct clk_hw *of_clk_hw_onecell_get(struct of_phandle_args *clkspec,
+ void *data);
unsigned int of_clk_get_parent_count(struct device_node *np);
int of_clk_parent_fill(struct device_node *np, const char **parents,
unsigned int size);
@@ -738,17 +751,34 @@ static inline int of_clk_add_provider(struct device_node *np,
{
return 0;
}
+static inline int of_clk_add_hw_provider(struct device_node *np,
+ struct clk_hw *(*get)(struct of_phandle_args *clkspec,
+ void *data),
+ void *data)
+{
+ return 0;
+}
static inline void of_clk_del_provider(struct device_node *np) {}
static inline struct clk *of_clk_src_simple_get(
struct of_phandle_args *clkspec, void *data)
{
return ERR_PTR(-ENOENT);
}
+static inline struct clk_hw *
+of_clk_hw_simple_get(struct of_phandle_args *clkspec, void *data)
+{
+ return ERR_PTR(-ENOENT);
+}
static inline struct clk *of_clk_src_onecell_get(
struct of_phandle_args *clkspec, void *data)
{
return ERR_PTR(-ENOENT);
}
+static inline struct clk_hw *
+of_clk_hw_onecell_get(struct of_phandle_args *clkspec, void *data)
+{
+ return ERR_PTR(-ENOENT);
+}
static inline int of_clk_get_parent_count(struct device_node *np)
{
return 0;