CLK: TI: add support for clockdomain binding

Some OMAP clocks require knowledge about their parent clockdomain for
book keeping purposes. This patch creates a new DT binding for TI
clockdomains, which act as a collection of device clocks. Clockdomain
itself is rather misleading name for the hardware functionality, as at
least on OMAP4 / OMAP5 / DRA7 the clockdomains can be collections of either
clocks and/or IP blocks, thus idle-domain or such might be more appropriate.
For most cases on these SoCs, the kernel doesn't even need the information
and the mappings can be ignored.

Signed-off-by: Tero Kristo <t-kristo@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>

2 files changed, 71 insertions, 1 deletions

diff --git a/drivers/clk/ti/Makefile b/drivers/clk/ti/Makefile
index eaa6dc0aeb75..ae7cd1e91cd2 100644
--- a/drivers/clk/ti/Makefile
+++ b/drivers/clk/ti/Makefile
@@ -1,5 +1,5 @@
 ifneq ($(CONFIG_OF),)
-obj-y                                   += clk.o autoidle.o
+obj-y                                   += clk.o autoidle.o clockdomain.o
 clk-common                              = dpll.o composite.o divider.o gate.o \
                                           fixed-factor.o
 endif
diff --git a/drivers/clk/ti/clockdomain.c b/drivers/clk/ti/clockdomain.c
new file mode 100644
index 000000000000..f1e0038d76ac
--- /dev/null
+++ b/drivers/clk/ti/clockdomain.c
@@ -0,0 +1,70 @@
+/*
+ * OMAP clockdomain 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 void __init of_ti_clockdomain_setup(struct device_node *node)
+{
+        struct clk *clk;
+        struct clk_hw *clk_hw;
+        const char *clkdm_name = node->name;
+        int i;
+        int num_clks;
+
+        num_clks = of_count_phandle_with_args(node, "clocks", "#clock-cells");
+
+        for (i = 0; i < num_clks; i++) {
+                clk = of_clk_get(node, i);
+                if (__clk_get_flags(clk) & CLK_IS_BASIC) {
+                        pr_warn("can't setup clkdm for basic clk %s\n",
+                                __clk_get_name(clk));
+                        continue;
+                }
+                clk_hw = __clk_get_hw(clk);
+                to_clk_hw_omap(clk_hw)->clkdm_name = clkdm_name;
+                omap2_init_clk_clkdm(clk_hw);
+        }
+}
+
+static struct of_device_id ti_clkdm_match_table[] __initdata = {
+        { .compatible = "ti,clockdomain" },
+        { }
+};
+
+/**
+ * ti_dt_clockdomains_setup - setup device tree clockdomains
+ *
+ * Initializes clockdomain nodes for a SoC. This parses through all the
+ * nodes with compatible = "ti,clockdomain", and add the clockdomain
+ * info for all the clocks listed under these. This function shall be
+ * called after rest of the DT clock init has completed and all
+ * clock nodes have been registered.
+ */
+void __init ti_dt_clockdomains_setup(void)
+{
+        struct device_node *np;
+        for_each_matching_node(np, ti_clkdm_match_table) {
+                of_ti_clockdomain_setup(np);
+        }
+}