clk: ux500: Initial support for abx500 clock driver

The abx500 clock driver is a platform driver which will be initialized
during arch init. The platform device shall be added from the ab-core
driver as a mfd child device to maintain correct boot sequence.

Depending on what ab version we use, different clock definitions will
be added.
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NMike Turquette <mturquette@linaro.org>

drivers/clk/ux500/Makefile

@@ -10,3 +10,6 @@ obj-y += clk-prcmu.o
 obj-y += u8500_clk.o
 obj-y += u9540_clk.o
 obj-y += u8540_clk.o
+
+# ABX500 clock driver
+obj-y += abx500-clk.o

drivers/clk/ux500/abx500-clk.c

+/*
+ * abx500 clock implementation for ux500 platform.
+ *
+ * Copyright (C) 2012 ST-Ericsson SA
+ * Author: Ulf Hansson <ulf.hansson@linaro.org>
+ *
+ * License terms: GNU General Public License (GPL) version 2
+ */
+
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/mfd/abx500/ab8500.h>
+
+/* TODO: Add clock implementations here */
+
+
+/* Clock definitions for ab8500 */
+static int ab8500_reg_clks(struct device *dev)
+{
+	return 0;
+}
+
+/* Clock definitions for ab8540 */
+static int ab8540_reg_clks(struct device *dev)
+{
+	return 0;
+}
+
+/* Clock definitions for ab9540 */
+static int ab9540_reg_clks(struct device *dev)
+{
+	return 0;
+}
+
+static int __devinit abx500_clk_probe(struct platform_device *pdev)
+{
+	struct ab8500 *parent = dev_get_drvdata(pdev->dev.parent);
+	int ret;
+
+	if (is_ab8500(parent) || is_ab8505(parent)) {
+		ret = ab8500_reg_clks(&pdev->dev);
+	} else if (is_ab8540(parent)) {
+		ret = ab8540_reg_clks(&pdev->dev);
+	} else if (is_ab9540(parent)) {
+		ret = ab9540_reg_clks(&pdev->dev);
+	} else {
+		dev_err(&pdev->dev, "non supported plf id\n");
+		return -ENODEV;
+	}
+
+	return ret;
+}
+
+static struct platform_driver abx500_clk_driver = {
+	.driver = {
+		.name = "abx500-clk",
+		.owner = THIS_MODULE,
+	},
+	.probe	= abx500_clk_probe,
+};
+
+static int __init abx500_clk_init(void)
+{
+	return platform_driver_register(&abx500_clk_driver);
+}
+
+arch_initcall(abx500_clk_init);
+
+MODULE_AUTHOR("Ulf Hansson <ulf.hansson@linaro.org");
+MODULE_DESCRIPTION("ABX500 clk driver");
+MODULE_LICENSE("GPL v2");