[PATCHv11 16/49] clk: ti: add support for TI fixed factor clock
Tero Kristo
t-kristo at ti.com
Thu Dec 19 06:23:47 EST 2013
This behaves exactly in similar manner to basic fixed-factor-clock, but
adds a few properties on top for handling clock hardware autoidling.
Signed-off-by: Tero Kristo <t-kristo at ti.com>
---
.../bindings/clock/ti/fixed-factor-clock.txt | 43 +++++++++++++
drivers/clk/ti/Makefile | 2 +-
drivers/clk/ti/fixed-factor.c | 66 ++++++++++++++++++++
3 files changed, 110 insertions(+), 1 deletion(-)
create mode 100644 Documentation/devicetree/bindings/clock/ti/fixed-factor-clock.txt
create mode 100644 drivers/clk/ti/fixed-factor.c
diff --git a/Documentation/devicetree/bindings/clock/ti/fixed-factor-clock.txt b/Documentation/devicetree/bindings/clock/ti/fixed-factor-clock.txt
new file mode 100644
index 0000000..662b36d
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/ti/fixed-factor-clock.txt
@@ -0,0 +1,43 @@
+Binding for TI fixed factor rate clock sources.
+
+Binding status: Unstable - ABI compatibility may be broken in the future
+
+This binding uses the common clock binding[1], and also uses the autoidle
+support from TI autoidle clock [2].
+
+[1] Documentation/devicetree/bindings/clock/clock-bindings.txt
+[2] Documentation/devicetree/bindings/clock/ti/autoidle.txt
+
+Required properties:
+- compatible : shall be "ti,fixed-factor-clock".
+- #clock-cells : from common clock binding; shall be set to 0.
+- ti,clock-div: fixed divider.
+- ti,clock-mult: fixed multiplier.
+- clocks: parent clock.
+
+Optional properties:
+- ti,autoidle-shift: bit shift of the autoidle enable bit for the clock,
+ see [2]
+- reg: offset for the autoidle register of this clock, see [2]
+- ti,invert-autoidle-bit: autoidle is enabled by setting the bit to 0, see [2]
+- ti,set-rate-parent: clk_set_rate is propagated to parent
+
+Example:
+ clock {
+ compatible = "ti,fixed-factor-clock";
+ clocks = <&parentclk>;
+ #clock-cells = <0>;
+ ti,clock-div = <2>;
+ ti,clock-mult = <1>;
+ };
+
+ dpll_usb_clkdcoldo_ck: dpll_usb_clkdcoldo_ck {
+ #clock-cells = <0>;
+ compatible = "ti,fixed-factor-clock";
+ clocks = <&dpll_usb_ck>;
+ ti,clock-div = <1>;
+ ti,autoidle-shift = <8>;
+ reg = <0x01b4>;
+ ti,clock-mult = <1>;
+ ti,invert-autoidle-bit;
+ };
diff --git a/drivers/clk/ti/Makefile b/drivers/clk/ti/Makefile
index 640ebf9..f57fc4b 100644
--- a/drivers/clk/ti/Makefile
+++ b/drivers/clk/ti/Makefile
@@ -1,4 +1,4 @@
ifneq ($(CONFIG_OF),)
obj-y += clk.o dpll.o autoidle.o divider.o \
- composite.o
+ fixed-factor.o composite.o
endif
diff --git a/drivers/clk/ti/fixed-factor.c b/drivers/clk/ti/fixed-factor.c
new file mode 100644
index 0000000..c2c8a28
--- /dev/null
+++ b/drivers/clk/ti/fixed-factor.c
@@ -0,0 +1,66 @@
+/*
+ * TI Fixed Factor Clock
+ *
+ * Copyright (C) 2013 Texas Instruments, Inc.
+ *
+ * Tero Kristo <t-kristo at 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/err.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__
+
+/**
+ * of_ti_fixed_factor_clk_setup - Setup function for TI fixed factor clock
+ * @node: device node for this clock
+ *
+ * Sets up a simple fixed factor clock based on device tree info.
+ */
+static void __init of_ti_fixed_factor_clk_setup(struct device_node *node)
+{
+ struct clk *clk;
+ const char *clk_name = node->name;
+ const char *parent_name;
+ u32 div, mult;
+ u32 flags = 0;
+
+ if (of_property_read_u32(node, "ti,clock-div", &div)) {
+ pr_err("%s must have a clock-div property\n", node->name);
+ return;
+ }
+
+ if (of_property_read_u32(node, "ti,clock-mult", &mult)) {
+ pr_err("%s must have a clock-mult property\n", node->name);
+ return;
+ }
+
+ if (of_property_read_bool(node, "ti,set-rate-parent"))
+ flags |= CLK_SET_RATE_PARENT;
+
+ parent_name = of_clk_get_parent_name(node, 0);
+
+ clk = clk_register_fixed_factor(NULL, clk_name, parent_name, flags,
+ mult, div);
+
+ if (!IS_ERR(clk)) {
+ of_clk_add_provider(node, of_clk_src_simple_get, clk);
+ of_ti_clk_autoidle_setup(node);
+ }
+}
+CLK_OF_DECLARE(ti_fixed_factor_clk, "ti,fixed-factor-clock",
+ of_ti_fixed_factor_clk_setup);
--
1.7.9.5
More information about the linux-arm-kernel
mailing list