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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /drivers/clk/clk-fixed-rate.c
Initial import
Diffstat (limited to 'drivers/clk/clk-fixed-rate.c')
-rw-r--r--drivers/clk/clk-fixed-rate.c137
1 files changed, 137 insertions, 0 deletions
diff --git a/drivers/clk/clk-fixed-rate.c b/drivers/clk/clk-fixed-rate.c
new file mode 100644
index 000000000..0fc56ab6e
--- /dev/null
+++ b/drivers/clk/clk-fixed-rate.c
@@ -0,0 +1,137 @@
+/*
+ * Copyright (C) 2010-2011 Canonical Ltd <jeremy.kerr@canonical.com>
+ * Copyright (C) 2011-2012 Mike Turquette, Linaro Ltd <mturquette@linaro.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Fixed rate clock implementation
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/err.h>
+#include <linux/of.h>
+
+/*
+ * DOC: basic fixed-rate clock that cannot gate
+ *
+ * Traits of this clock:
+ * prepare - clk_(un)prepare only ensures parents are prepared
+ * enable - clk_enable only ensures parents are enabled
+ * rate - rate is always a fixed value. No clk_set_rate support
+ * parent - fixed parent. No clk_set_parent support
+ */
+
+#define to_clk_fixed_rate(_hw) container_of(_hw, struct clk_fixed_rate, hw)
+
+static unsigned long clk_fixed_rate_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ return to_clk_fixed_rate(hw)->fixed_rate;
+}
+
+static unsigned long clk_fixed_rate_recalc_accuracy(struct clk_hw *hw,
+ unsigned long parent_accuracy)
+{
+ return to_clk_fixed_rate(hw)->fixed_accuracy;
+}
+
+const struct clk_ops clk_fixed_rate_ops = {
+ .recalc_rate = clk_fixed_rate_recalc_rate,
+ .recalc_accuracy = clk_fixed_rate_recalc_accuracy,
+};
+EXPORT_SYMBOL_GPL(clk_fixed_rate_ops);
+
+/**
+ * clk_register_fixed_rate_with_accuracy - register fixed-rate clock with the
+ * clock framework
+ * @dev: device that is registering this clock
+ * @name: name of this clock
+ * @parent_name: name of clock's parent
+ * @flags: framework-specific flags
+ * @fixed_rate: non-adjustable clock rate
+ * @fixed_accuracy: non-adjustable clock rate
+ */
+struct clk *clk_register_fixed_rate_with_accuracy(struct device *dev,
+ const char *name, const char *parent_name, unsigned long flags,
+ unsigned long fixed_rate, unsigned long fixed_accuracy)
+{
+ struct clk_fixed_rate *fixed;
+ struct clk *clk;
+ struct clk_init_data init;
+
+ /* allocate fixed-rate clock */
+ fixed = kzalloc(sizeof(struct clk_fixed_rate), GFP_KERNEL);
+ if (!fixed) {
+ pr_err("%s: could not allocate fixed clk\n", __func__);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ init.name = name;
+ init.ops = &clk_fixed_rate_ops;
+ init.flags = flags | CLK_IS_BASIC;
+ init.parent_names = (parent_name ? &parent_name: NULL);
+ init.num_parents = (parent_name ? 1 : 0);
+
+ /* struct clk_fixed_rate assignments */
+ fixed->fixed_rate = fixed_rate;
+ fixed->fixed_accuracy = fixed_accuracy;
+ fixed->hw.init = &init;
+
+ /* register the clock */
+ clk = clk_register(dev, &fixed->hw);
+ if (IS_ERR(clk))
+ kfree(fixed);
+
+ return clk;
+}
+EXPORT_SYMBOL_GPL(clk_register_fixed_rate_with_accuracy);
+
+/**
+ * clk_register_fixed_rate - register fixed-rate clock with the clock framework
+ * @dev: device that is registering this clock
+ * @name: name of this clock
+ * @parent_name: name of clock's parent
+ * @flags: framework-specific flags
+ * @fixed_rate: non-adjustable clock rate
+ */
+struct clk *clk_register_fixed_rate(struct device *dev, const char *name,
+ const char *parent_name, unsigned long flags,
+ unsigned long fixed_rate)
+{
+ return clk_register_fixed_rate_with_accuracy(dev, name, parent_name,
+ flags, fixed_rate, 0);
+}
+EXPORT_SYMBOL_GPL(clk_register_fixed_rate);
+
+#ifdef CONFIG_OF
+/**
+ * of_fixed_clk_setup() - Setup function for simple fixed rate clock
+ */
+void of_fixed_clk_setup(struct device_node *node)
+{
+ struct clk *clk;
+ const char *clk_name = node->name;
+ u32 rate;
+ u32 accuracy = 0;
+
+ if (of_property_read_u32(node, "clock-frequency", &rate))
+ return;
+
+ of_property_read_u32(node, "clock-accuracy", &accuracy);
+
+ of_property_read_string(node, "clock-output-names", &clk_name);
+
+ clk = clk_register_fixed_rate_with_accuracy(NULL, clk_name, NULL,
+ CLK_IS_ROOT, rate,
+ accuracy);
+ if (!IS_ERR(clk))
+ of_clk_add_provider(node, of_clk_src_simple_get, clk);
+}
+EXPORT_SYMBOL_GPL(of_fixed_clk_setup);
+CLK_OF_DECLARE(fixed_clk, "fixed-clock", of_fixed_clk_setup);
+#endif