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authorShawn Guo <shawn.guo@linaro.org>2012-04-28 20:02:34 +0400
committerShawn Guo <shawn.guo@linaro.org>2012-05-08 20:02:35 +0400
commit23b5e15a2994fb0c1444f92b76f09a482f32843c (patch)
tree54695e5b39977bd1ed04dfd945c9052a85b57e0f /drivers/clk/mxs/clk-pll.c
parentd48b97b403d23f6df0b990cee652bdf9a52337a3 (diff)
downloadlinux-23b5e15a2994fb0c1444f92b76f09a482f32843c.tar.xz
clk: mxs: add mxs specific clocks
Add mxs specific clocks, pll, reference clock (PFD), integer divider and fractional divider. Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Diffstat (limited to 'drivers/clk/mxs/clk-pll.c')
-rw-r--r--drivers/clk/mxs/clk-pll.c116
1 files changed, 116 insertions, 0 deletions
diff --git a/drivers/clk/mxs/clk-pll.c b/drivers/clk/mxs/clk-pll.c
new file mode 100644
index 000000000000..fadae41833ec
--- /dev/null
+++ b/drivers/clk/mxs/clk-pll.c
@@ -0,0 +1,116 @@
+/*
+ * 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/delay.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include "clk.h"
+
+/**
+ * struct clk_pll - mxs pll clock
+ * @hw: clk_hw for the pll
+ * @base: base address of the pll
+ * @power: the shift of power bit
+ * @rate: the clock rate of the pll
+ *
+ * The mxs pll is a fixed rate clock with power and gate control,
+ * and the shift of gate bit is always 31.
+ */
+struct clk_pll {
+ struct clk_hw hw;
+ void __iomem *base;
+ u8 power;
+ unsigned long rate;
+};
+
+#define to_clk_pll(_hw) container_of(_hw, struct clk_pll, hw)
+
+static int clk_pll_prepare(struct clk_hw *hw)
+{
+ struct clk_pll *pll = to_clk_pll(hw);
+
+ writel_relaxed(1 << pll->power, pll->base + SET);
+
+ udelay(10);
+
+ return 0;
+}
+
+static void clk_pll_unprepare(struct clk_hw *hw)
+{
+ struct clk_pll *pll = to_clk_pll(hw);
+
+ writel_relaxed(1 << pll->power, pll->base + CLR);
+}
+
+static int clk_pll_enable(struct clk_hw *hw)
+{
+ struct clk_pll *pll = to_clk_pll(hw);
+
+ writel_relaxed(1 << 31, pll->base + CLR);
+
+ return 0;
+}
+
+static void clk_pll_disable(struct clk_hw *hw)
+{
+ struct clk_pll *pll = to_clk_pll(hw);
+
+ writel_relaxed(1 << 31, pll->base + SET);
+}
+
+static unsigned long clk_pll_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct clk_pll *pll = to_clk_pll(hw);
+
+ return pll->rate;
+}
+
+static const struct clk_ops clk_pll_ops = {
+ .prepare = clk_pll_prepare,
+ .unprepare = clk_pll_unprepare,
+ .enable = clk_pll_enable,
+ .disable = clk_pll_disable,
+ .recalc_rate = clk_pll_recalc_rate,
+};
+
+struct clk *mxs_clk_pll(const char *name, const char *parent_name,
+ void __iomem *base, u8 power, unsigned long rate)
+{
+ struct clk_pll *pll;
+ struct clk *clk;
+ struct clk_init_data init;
+
+ pll = kzalloc(sizeof(*pll), GFP_KERNEL);
+ if (!pll)
+ return ERR_PTR(-ENOMEM);
+
+ init.name = name;
+ init.ops = &clk_pll_ops;
+ init.flags = 0;
+ init.parent_names = (parent_name ? &parent_name: NULL);
+ init.num_parents = (parent_name ? 1 : 0);
+
+ pll->base = base;
+ pll->rate = rate;
+ pll->power = power;
+ pll->hw.init = &init;
+
+ clk = clk_register(NULL, &pll->hw);
+ if (IS_ERR(clk))
+ kfree(pll);
+
+ return clk;
+}