1 files changed, 210 insertions, 0 deletions
diff --git a/drivers/clk/clk-composite.c b/drivers/clk/clk-composite.c
new file mode 100644
index 00000000000..a33f46f20a4
--- /dev/null
+++ b/drivers/clk/clk-composite.c
@@ -0,0 +1,210 @@
+/*
+ * Copyright (c) 2013 NVIDIA CORPORATION.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+
+#define to_clk_composite(_hw) container_of(_hw, struct clk_composite, hw)
+
+static u8 clk_composite_get_parent(struct clk_hw *hw)
+{
+	struct clk_composite *composite = to_clk_composite(hw);
+	const struct clk_ops *mux_ops = composite->mux_ops;
+	struct clk_hw *mux_hw = composite->mux_hw;
+
+	mux_hw->clk = hw->clk;
+
+	return mux_ops->get_parent(mux_hw);
+}
+
+static int clk_composite_set_parent(struct clk_hw *hw, u8 index)
+{
+	struct clk_composite *composite = to_clk_composite(hw);
+	const struct clk_ops *mux_ops = composite->mux_ops;
+	struct clk_hw *mux_hw = composite->mux_hw;
+
+	mux_hw->clk = hw->clk;
+
+	return mux_ops->set_parent(mux_hw, index);
+}
+
+static unsigned long clk_composite_recalc_rate(struct clk_hw *hw,
+					    unsigned long parent_rate)
+{
+	struct clk_composite *composite = to_clk_composite(hw);
+	const struct clk_ops *rate_ops = composite->rate_ops;
+	struct clk_hw *rate_hw = composite->rate_hw;
+
+	rate_hw->clk = hw->clk;
+
+	return rate_ops->recalc_rate(rate_hw, parent_rate);
+}
+
+static long clk_composite_round_rate(struct clk_hw *hw, unsigned long rate,
+				  unsigned long *prate)
+{
+	struct clk_composite *composite = to_clk_composite(hw);
+	const struct clk_ops *rate_ops = composite->rate_ops;
+	struct clk_hw *rate_hw = composite->rate_hw;
+
+	rate_hw->clk = hw->clk;
+
+	return rate_ops->round_rate(rate_hw, rate, prate);
+}
+
+static int clk_composite_set_rate(struct clk_hw *hw, unsigned long rate,
+			       unsigned long parent_rate)
+{
+	struct clk_composite *composite = to_clk_composite(hw);
+	const struct clk_ops *rate_ops = composite->rate_ops;
+	struct clk_hw *rate_hw = composite->rate_hw;
+
+	rate_hw->clk = hw->clk;
+
+	return rate_ops->set_rate(rate_hw, rate, parent_rate);
+}
+
+static int clk_composite_is_enabled(struct clk_hw *hw)
+{
+	struct clk_composite *composite = to_clk_composite(hw);
+	const struct clk_ops *gate_ops = composite->gate_ops;
+	struct clk_hw *gate_hw = composite->gate_hw;
+
+	gate_hw->clk = hw->clk;
+
+	return gate_ops->is_enabled(gate_hw);
+}
+
+static int clk_composite_enable(struct clk_hw *hw)
+{
+	struct clk_composite *composite = to_clk_composite(hw);
+	const struct clk_ops *gate_ops = composite->gate_ops;
+	struct clk_hw *gate_hw = composite->gate_hw;
+
+	gate_hw->clk = hw->clk;
+
+	return gate_ops->enable(gate_hw);
+}
+
+static void clk_composite_disable(struct clk_hw *hw)
+{
+	struct clk_composite *composite = to_clk_composite(hw);
+	const struct clk_ops *gate_ops = composite->gate_ops;
+	struct clk_hw *gate_hw = composite->gate_hw;
+
+	gate_hw->clk = hw->clk;
+
+	gate_ops->disable(gate_hw);
+}
+
+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 *rate_hw, const struct clk_ops *rate_ops,
+			struct clk_hw *gate_hw, const struct clk_ops *gate_ops,
+			unsigned long flags)
+{
+	struct clk *clk;
+	struct clk_init_data init;
+	struct clk_composite *composite;
+	struct clk_ops *clk_composite_ops;
+
+	composite = kzalloc(sizeof(*composite), GFP_KERNEL);
+	if (!composite) {
+		pr_err("%s: could not allocate composite clk\n", __func__);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	init.name = name;
+	init.flags = flags | CLK_IS_BASIC;
+	init.parent_names = parent_names;
+	init.num_parents = num_parents;
+
+	clk_composite_ops = &composite->ops;
+
+	if (mux_hw && mux_ops) {
+		if (!mux_ops->get_parent || !mux_ops->set_parent) {
+			clk = ERR_PTR(-EINVAL);
+			goto err;
+		}
+
+		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 (rate_hw && rate_ops) {
+		if (!rate_ops->recalc_rate) {
+			clk = ERR_PTR(-EINVAL);
+			goto err;
+		}
+
+		/* .round_rate is a prerequisite for .set_rate */
+		if (rate_ops->round_rate) {
+			clk_composite_ops->round_rate = clk_composite_round_rate;
+			if (rate_ops->set_rate) {
+				clk_composite_ops->set_rate = clk_composite_set_rate;
+			}
+		} else {
+			WARN(rate_ops->set_rate,
+				"%s: missing round_rate op is required\n",
+				__func__);
+		}
+
+		composite->rate_hw = rate_hw;
+		composite->rate_ops = rate_ops;
+		clk_composite_ops->recalc_rate = clk_composite_recalc_rate;
+	}
+
+	if (gate_hw && gate_ops) {
+		if (!gate_ops->is_enabled || !gate_ops->enable ||
+		    !gate_ops->disable) {
+			clk = ERR_PTR(-EINVAL);
+			goto err;
+		}
+
+		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;
+	composite->hw.init = &init;
+
+	clk = clk_register(dev, &composite->hw);
+	if (IS_ERR(clk))
+		goto err;
+
+	if (composite->mux_hw)
+		composite->mux_hw->clk = clk;
+
+	if (composite->rate_hw)
+		composite->rate_hw->clk = clk;
+
+	if (composite->gate_hw)
+		composite->gate_hw->clk = clk;
+
+	return clk;
+
+err:
+	kfree(composite);
+	return clk;
+}