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path: root/drivers/clk/mxs/clk-div.c
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Diffstat (limited to 'drivers/clk/mxs/clk-div.c')
-rw-r--r--drivers/clk/mxs/clk-div.c110
1 files changed, 110 insertions, 0 deletions
diff --git a/drivers/clk/mxs/clk-div.c b/drivers/clk/mxs/clk-div.c
new file mode 100644
index 000000000000..90e1da93877e
--- /dev/null
+++ b/drivers/clk/mxs/clk-div.c
@@ -0,0 +1,110 @@
+/*
+ * Copyright 2012 Freescale Semiconductor, Inc.
+ *
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include "clk.h"
+
+/**
+ * struct clk_div - mxs integer divider clock
+ * @divider: the parent class
+ * @ops: pointer to clk_ops of parent class
+ * @reg: register address
+ * @busy: busy bit shift
+ *
+ * The mxs divider clock is a subclass of basic clk_divider with an
+ * addtional busy bit.
+ */
+struct clk_div {
+ struct clk_divider divider;
+ const struct clk_ops *ops;
+ void __iomem *reg;
+ u8 busy;
+};
+
+static inline struct clk_div *to_clk_div(struct clk_hw *hw)
+{
+ struct clk_divider *divider = container_of(hw, struct clk_divider, hw);
+
+ return container_of(divider, struct clk_div, divider);
+}
+
+static unsigned long clk_div_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct clk_div *div = to_clk_div(hw);
+
+ return div->ops->recalc_rate(&div->divider.hw, parent_rate);
+}
+
+static long clk_div_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *prate)
+{
+ struct clk_div *div = to_clk_div(hw);
+
+ return div->ops->round_rate(&div->divider.hw, rate, prate);
+}
+
+static int clk_div_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct clk_div *div = to_clk_div(hw);
+ int ret;
+
+ ret = div->ops->set_rate(&div->divider.hw, rate, parent_rate);
+ if (!ret)
+ ret = mxs_clk_wait(div->reg, div->busy);
+
+ return ret;
+}
+
+static struct clk_ops clk_div_ops = {
+ .recalc_rate = clk_div_recalc_rate,
+ .round_rate = clk_div_round_rate,
+ .set_rate = clk_div_set_rate,
+};
+
+struct clk *mxs_clk_div(const char *name, const char *parent_name,
+ void __iomem *reg, u8 shift, u8 width, u8 busy)
+{
+ struct clk_div *div;
+ struct clk *clk;
+ struct clk_init_data init;
+
+ div = kzalloc(sizeof(*div), GFP_KERNEL);
+ if (!div)
+ return ERR_PTR(-ENOMEM);
+
+ init.name = name;
+ init.ops = &clk_div_ops;
+ init.flags = CLK_SET_RATE_PARENT;
+ init.parent_names = (parent_name ? &parent_name: NULL);
+ init.num_parents = (parent_name ? 1 : 0);
+
+ div->reg = reg;
+ div->busy = busy;
+
+ div->divider.reg = reg;
+ div->divider.shift = shift;
+ div->divider.width = width;
+ div->divider.flags = CLK_DIVIDER_ONE_BASED;
+ div->divider.lock = &mxs_lock;
+ div->divider.hw.init = &init;
+ div->ops = &clk_divider_ops;
+
+ clk = clk_register(NULL, &div->divider.hw);
+ if (IS_ERR(clk))
+ kfree(div);
+
+ return clk;
+}