[PATCH V2] clk: Add composite clock type

Hiroshi Doyu
2013-02-05T10:22:52Z

Prashant Gaikwad <pgaikwad@nvidia.com> wrote @ Tue, 5 Feb 2013 09:33:41 +0100:

> > The members of "clk_composite_ops" seems to be always assigned
> > statically. Istead of dynamically allocating/assigning, can't we just
> > have "clk_composite_ops" statically as below?
> >
> > static struct clk_ops clk_composite_ops = {
> > .get_parent = clk_composite_get_parent;
> > .set_parent = clk_composite_set_parent;
> > .recalc_rate = clk_composite_recalc_rate;
> > .round_rate = clk_composite_round_rate;
> > .set_rate = clk_composite_set_rate;
> > .is_enabled = clk_composite_is_enabled;
> > .enable = clk_composite_enable;
> > .disable = clk_composite_disable;
> > };
> >
> > struct clk *clk_register_composite(struct device *dev, const char *name,
> > const char **parent_names, int num_parents,
> > struct clk_hw *mux_hw, const struct clk_ops *mux_ops,
> > struct clk_hw *div_hw, const struct clk_ops *div_ops,
> > struct clk_hw *gate_hw, const struct clk_ops *gate_ops,
> > unsigned long flags)
> > {
> > .....
> >
> > init.ops = &clk_composite_ops;
>
> No, clk_ops depends on the clocks you are using. There could be a clock
> with mux and gate while another one with mux and div.

You are right. What about the following? We don't have to have similar
copy of clk_composite_ops for each instances.

diff --git a/drivers/clk/clk-composite.c b/drivers/clk/clk-composite.c
index f30fb4b..8f88805 100644
--- a/drivers/clk/clk-composite.c
+++ b/drivers/clk/clk-composite.c
@@ -27,6 +27,9 @@ static u8 clk_composite_get_parent(struct clk_hw *hw)
const struct clk_ops *mux_ops = composite->mux_ops;
struct clk_hw *mux_hw = composite->mux_hw;

+ if (!mux_hw->clk)
+ return -EINVAL;
+
mux_hw->clk = hw->clk;

return mux_ops->get_parent(mux_hw);
@@ -38,6 +41,9 @@ static int clk_composite_set_parent(struct clk_hw *hw, u8 index)
const struct clk_ops *mux_ops = composite->mux_ops;
struct clk_hw *mux_hw = composite->mux_hw;

+ if (!mux_hw->clk)
+ return -EINVAL;
+
mux_hw->clk = hw->clk;

return mux_ops->set_parent(mux_hw, index);
@@ -50,6 +56,9 @@ static unsigned long clk_composite_recalc_rate(struct clk_hw *hw,
const struct clk_ops *div_ops = composite->div_ops;
struct clk_hw *div_hw = composite->div_hw;

+ if (!div_hw->clk)
+ return -EINVAL;
+
div_hw->clk = hw->clk;

return div_ops->recalc_rate(div_hw, parent_rate);
@@ -62,6 +71,9 @@ static long clk_composite_round_rate(struct clk_hw *hw, unsigned long rate,
const struct clk_ops *div_ops = composite->div_ops;
struct clk_hw *div_hw = composite->div_hw;

+ if (!div_hw->clk)
+ return -EINVAL;
+
div_hw->clk = hw->clk;

return div_ops->round_rate(div_hw, rate, prate);
@@ -74,6 +86,9 @@ static int clk_composite_set_rate(struct clk_hw *hw, unsigned long rate,
const struct clk_ops *div_ops = composite->div_ops;
struct clk_hw *div_hw = composite->div_hw;

+ if (!div_hw->clk)
+ return -EINVAL;
+
div_hw->clk = hw->clk;

return div_ops->set_rate(div_hw, rate, parent_rate);
@@ -85,6 +100,9 @@ static int clk_composite_is_enabled(struct clk_hw *hw)
const struct clk_ops *gate_ops = composite->gate_ops;
struct clk_hw *gate_hw = composite->gate_hw;

+ if (!gate_hw->clk)
+ return -EINVAL;
+
gate_hw->clk = hw->clk;

return gate_ops->is_enabled(gate_hw);
@@ -96,6 +114,9 @@ static int clk_composite_enable(struct clk_hw *hw)
const struct clk_ops *gate_ops = composite->gate_ops;
struct clk_hw *gate_hw = composite->gate_hw;

+ if (!gate_hw->clk)
+ return -EINVAL;
+
gate_hw->clk = hw->clk;

return gate_ops->enable(gate_hw);
@@ -107,11 +128,25 @@ static void clk_composite_disable(struct clk_hw *hw)
const struct clk_ops *gate_ops = composite->gate_ops;
struct clk_hw *gate_hw = composite->gate_hw;

+ if (!gate_hw->clk)
+ return -EINVAL;
+
gate_hw->clk = hw->clk;

gate_ops->disable(gate_hw);
}

+static struct clk_ops clk_composite_ops = {
+ .get_parent = clk_composite_get_parent,
+ .set_parent = clk_composite_set_parent,
+ .recalc_rate = clk_composite_recalc_rate,
+ .round_rate = clk_composite_round_rate,
+ .set_rate = clk_composite_set_rate,
+ .is_enabled = clk_composite_is_enabled,
+ .enable = clk_composite_enable,
+ .disable = clk_composite_disable,
+};
+
struct clk *clk_register_composite(struct device *dev, const char *name,
const char **parent_names, int num_parents,
struct clk_hw *mux_hw, const struct clk_ops *mux_ops,
@@ -135,14 +170,6 @@ struct clk *clk_register_composite(struct device *dev, const char *name,
init.parent_names = parent_names;
init.num_parents = num_parents;

- /* allocate the clock ops */
- clk_composite_ops = kzalloc(sizeof(*clk_composite_ops), GFP_KERNEL);
- if (!clk_composite_ops) {
- pr_err("%s: could not allocate clk ops\n", __func__);
- kfree(composite);
- return ERR_PTR(-ENOMEM);
- }
-
if (mux_hw && mux_ops) {
if (!mux_ops->get_parent || !mux_ops->set_parent) {
clk = ERR_PTR(-EINVAL);
@@ -151,8 +178,6 @@ struct clk *clk_register_composite(struct device *dev, const char *name,

composite->mux_hw = mux_hw;
composite->mux_ops = mux_ops;
- clk_composite_ops->get_parent = clk_composite_get_parent;
- clk_composite_ops->set_parent = clk_composite_set_parent;
}

if (div_hw && div_ops) {
@@ -164,9 +189,6 @@ struct clk *clk_register_composite(struct device *dev, const char *name,

composite->div_hw = div_hw;
composite->div_ops = div_ops;
- clk_composite_ops->recalc_rate = clk_composite_recalc_rate;
- clk_composite_ops->round_rate = clk_composite_round_rate;
- clk_composite_ops->set_rate = clk_composite_set_rate;
}

if (gate_hw && gate_ops) {
@@ -178,12 +200,9 @@ struct clk *clk_register_composite(struct device *dev, const char *name,

composite->gate_hw = gate_hw;
composite->gate_ops = gate_ops;
- clk_composite_ops->is_enabled = clk_composite_is_enabled;
- clk_composite_ops->enable = clk_composite_enable;
- clk_composite_ops->disable = clk_composite_disable;
}

- init.ops = clk_composite_ops;
+ init.ops = &clk_composite_ops;
composite->hw.init = &init;

clk = clk_register(dev, &composite->hw);
@@ -202,7 +221,6 @@ struct clk *clk_register_composite(struct device *dev, const char *name,
return clk;

err:
- kfree(clk_composite_ops);
kfree(composite);
return clk;
}