CLK: TI: add interface clock support for OMAP3

OMAP3 has interface clocks in addition to functional clocks, which
require special handling for the autoidle and idle status register
offsets mainly.

Signed-off-by: Tero Kristo <t-kristo@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
diff --git a/drivers/clk/ti/interface.c b/drivers/clk/ti/interface.c
new file mode 100644
index 0000000..320a2b1
--- /dev/null
+++ b/drivers/clk/ti/interface.c
@@ -0,0 +1,125 @@
+/*
+ * OMAP interface clock support
+ *
+ * Copyright (C) 2013 Texas Instruments, Inc.
+ *
+ * Tero Kristo <t-kristo@ti.com>
+ *
+ * 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 "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/clk/ti.h>
+
+#undef pr_fmt
+#define pr_fmt(fmt) "%s: " fmt, __func__
+
+static const struct clk_ops ti_interface_clk_ops = {
+	.init		= &omap2_init_clk_clkdm,
+	.enable		= &omap2_dflt_clk_enable,
+	.disable	= &omap2_dflt_clk_disable,
+	.is_enabled	= &omap2_dflt_clk_is_enabled,
+};
+
+static void __init _of_ti_interface_clk_setup(struct device_node *node,
+					      const struct clk_hw_omap_ops *ops)
+{
+	struct clk *clk;
+	struct clk_init_data init = { NULL };
+	struct clk_hw_omap *clk_hw;
+	const char *parent_name;
+	u32 val;
+
+	clk_hw = kzalloc(sizeof(*clk_hw), GFP_KERNEL);
+	if (!clk_hw)
+		return;
+
+	clk_hw->hw.init = &init;
+	clk_hw->ops = ops;
+	clk_hw->flags = MEMMAP_ADDRESSING;
+
+	clk_hw->enable_reg = ti_clk_get_reg_addr(node, 0);
+	if (!clk_hw->enable_reg)
+		goto cleanup;
+
+	if (!of_property_read_u32(node, "ti,bit-shift", &val))
+		clk_hw->enable_bit = val;
+
+	init.name = node->name;
+	init.ops = &ti_interface_clk_ops;
+	init.flags = 0;
+
+	parent_name = of_clk_get_parent_name(node, 0);
+	if (!parent_name) {
+		pr_err("%s must have a parent\n", node->name);
+		goto cleanup;
+	}
+
+	init.num_parents = 1;
+	init.parent_names = &parent_name;
+
+	clk = clk_register(NULL, &clk_hw->hw);
+
+	if (!IS_ERR(clk)) {
+		of_clk_add_provider(node, of_clk_src_simple_get, clk);
+		omap2_init_clk_hw_omap_clocks(clk);
+		return;
+	}
+
+cleanup:
+	kfree(clk_hw);
+}
+
+static void __init of_ti_interface_clk_setup(struct device_node *node)
+{
+	_of_ti_interface_clk_setup(node, &clkhwops_iclk_wait);
+}
+CLK_OF_DECLARE(ti_interface_clk, "ti,omap3-interface-clock",
+	       of_ti_interface_clk_setup);
+
+static void __init of_ti_no_wait_interface_clk_setup(struct device_node *node)
+{
+	_of_ti_interface_clk_setup(node, &clkhwops_iclk);
+}
+CLK_OF_DECLARE(ti_no_wait_interface_clk, "ti,omap3-no-wait-interface-clock",
+	       of_ti_no_wait_interface_clk_setup);
+
+static void __init of_ti_hsotgusb_interface_clk_setup(struct device_node *node)
+{
+	_of_ti_interface_clk_setup(node,
+				   &clkhwops_omap3430es2_iclk_hsotgusb_wait);
+}
+CLK_OF_DECLARE(ti_hsotgusb_interface_clk, "ti,omap3-hsotgusb-interface-clock",
+	       of_ti_hsotgusb_interface_clk_setup);
+
+static void __init of_ti_dss_interface_clk_setup(struct device_node *node)
+{
+	_of_ti_interface_clk_setup(node,
+				   &clkhwops_omap3430es2_iclk_dss_usbhost_wait);
+}
+CLK_OF_DECLARE(ti_dss_interface_clk, "ti,omap3-dss-interface-clock",
+	       of_ti_dss_interface_clk_setup);
+
+static void __init of_ti_ssi_interface_clk_setup(struct device_node *node)
+{
+	_of_ti_interface_clk_setup(node, &clkhwops_omap3430es2_iclk_ssi_wait);
+}
+CLK_OF_DECLARE(ti_ssi_interface_clk, "ti,omap3-ssi-interface-clock",
+	       of_ti_ssi_interface_clk_setup);
+
+static void __init of_ti_am35xx_interface_clk_setup(struct device_node *node)
+{
+	_of_ti_interface_clk_setup(node, &clkhwops_am35xx_ipss_wait);
+}
+CLK_OF_DECLARE(ti_am35xx_interface_clk, "ti,am35xx-interface-clock",
+	       of_ti_am35xx_interface_clk_setup);