1 files changed, 131 insertions, 0 deletions
diff --git a/drivers/clk/versatile/clk-vexpress-osc.c b/drivers/clk/versatile/clk-vexpress-osc.c
new file mode 100644
index 000000000..dd08ecb49
--- /dev/null
+++ b/drivers/clk/versatile/clk-vexpress-osc.c
@@ -0,0 +1,131 @@
+/*
+ * 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.
+ *
+ * This program is distributed in the hope that 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.
+ *
+ * Copyright (C) 2012 ARM Limited
+ */
+
+#include <linux/clkdev.h>
+#include <linux/clk-provider.h>
+#include <linux/err.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/vexpress.h>
+
+struct vexpress_osc {
+	struct regmap *reg;
+	struct clk_hw hw;
+	unsigned long rate_min;
+	unsigned long rate_max;
+};
+
+#define to_vexpress_osc(osc) container_of(osc, struct vexpress_osc, hw)
+
+static unsigned long vexpress_osc_recalc_rate(struct clk_hw *hw,
+		unsigned long parent_rate)
+{
+	struct vexpress_osc *osc = to_vexpress_osc(hw);
+	u32 rate;
+
+	regmap_read(osc->reg, 0, &rate);
+
+	return rate;
+}
+
+static long vexpress_osc_round_rate(struct clk_hw *hw, unsigned long rate,
+		unsigned long *parent_rate)
+{
+	struct vexpress_osc *osc = to_vexpress_osc(hw);
+
+	if (osc->rate_min && rate < osc->rate_min)
+		rate = osc->rate_min;
+
+	if (osc->rate_max && rate > osc->rate_max)
+		rate = osc->rate_max;
+
+	return rate;
+}
+
+static int vexpress_osc_set_rate(struct clk_hw *hw, unsigned long rate,
+		unsigned long parent_rate)
+{
+	struct vexpress_osc *osc = to_vexpress_osc(hw);
+
+	return regmap_write(osc->reg, 0, rate);
+}
+
+static const struct clk_ops vexpress_osc_ops = {
+	.recalc_rate = vexpress_osc_recalc_rate,
+	.round_rate = vexpress_osc_round_rate,
+	.set_rate = vexpress_osc_set_rate,
+};
+
+
+static int vexpress_osc_probe(struct platform_device *pdev)
+{
+	struct clk_init_data init;
+	struct vexpress_osc *osc;
+	struct clk *clk;
+	u32 range[2];
+
+	osc = devm_kzalloc(&pdev->dev, sizeof(*osc), GFP_KERNEL);
+	if (!osc)
+		return -ENOMEM;
+
+	osc->reg = devm_regmap_init_vexpress_config(&pdev->dev);
+	if (IS_ERR(osc->reg))
+		return PTR_ERR(osc->reg);
+
+	if (of_property_read_u32_array(pdev->dev.of_node, "freq-range", range,
+			ARRAY_SIZE(range)) == 0) {
+		osc->rate_min = range[0];
+		osc->rate_max = range[1];
+	}
+
+	if (of_property_read_string(pdev->dev.of_node, "clock-output-names",
+			&init.name) != 0)
+		init.name = dev_name(&pdev->dev);
+
+	init.ops = &vexpress_osc_ops;
+	init.flags = 0;
+	init.num_parents = 0;
+
+	osc->hw.init = &init;
+
+	clk = clk_register(NULL, &osc->hw);
+	if (IS_ERR(clk))
+		return PTR_ERR(clk);
+
+	of_clk_add_provider(pdev->dev.of_node, of_clk_src_simple_get, clk);
+	clk_hw_set_rate_range(&osc->hw, osc->rate_min, osc->rate_max);
+
+	dev_dbg(&pdev->dev, "Registered clock '%s'\n", init.name);
+
+	return 0;
+}
+
+static const struct of_device_id vexpress_osc_of_match[] = {
+	{ .compatible = "arm,vexpress-osc", },
+	{}
+};
+
+static struct platform_driver vexpress_osc_driver = {
+	.driver	= {
+		.name = "vexpress-osc",
+		.of_match_table = vexpress_osc_of_match,
+	},
+	.probe = vexpress_osc_probe,
+};
+
+static int __init vexpress_osc_init(void)
+{
+	return platform_driver_register(&vexpress_osc_driver);
+}
+core_initcall(vexpress_osc_init);