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Diffstat (limited to 'kernel/drivers/clk/h8300/clk-div.c')
-rw-r--r--kernel/drivers/clk/h8300/clk-div.c55
1 files changed, 55 insertions, 0 deletions
diff --git a/kernel/drivers/clk/h8300/clk-div.c b/kernel/drivers/clk/h8300/clk-div.c
new file mode 100644
index 000000000..d71d01157
--- /dev/null
+++ b/kernel/drivers/clk/h8300/clk-div.c
@@ -0,0 +1,55 @@
+/*
+ * H8/300 divide clock driver
+ *
+ * Copyright 2015 Yoshinori Sato <ysato@users.sourceforge.jp>
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/err.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+
+static DEFINE_SPINLOCK(clklock);
+
+static void __init h8300_div_clk_setup(struct device_node *node)
+{
+ int num_parents;
+ struct clk *clk;
+ const char *clk_name = node->name;
+ const char *parent_name;
+ void __iomem *divcr = NULL;
+ int width;
+ int offset;
+
+ num_parents = of_clk_get_parent_count(node);
+ if (num_parents < 1) {
+ pr_err("%s: no parent found", clk_name);
+ return;
+ }
+
+ divcr = of_iomap(node, 0);
+ if (divcr == NULL) {
+ pr_err("%s: failed to map divide register", clk_name);
+ goto error;
+ }
+ offset = (unsigned long)divcr & 3;
+ offset = (3 - offset) * 8;
+ divcr = (void *)((unsigned long)divcr & ~3);
+
+ parent_name = of_clk_get_parent_name(node, 0);
+ of_property_read_u32(node, "renesas,width", &width);
+ clk = clk_register_divider(NULL, clk_name, parent_name,
+ CLK_SET_RATE_GATE, divcr, offset, width,
+ CLK_DIVIDER_POWER_OF_TWO, &clklock);
+ if (!IS_ERR(clk)) {
+ of_clk_add_provider(node, of_clk_src_simple_get, clk);
+ return;
+ }
+ pr_err("%s: failed to register %s div clock (%ld)\n",
+ __func__, clk_name, PTR_ERR(clk));
+error:
+ if (divcr)
+ iounmap(divcr);
+}
+
+CLK_OF_DECLARE(h8300_div_clk, "renesas,h8300-div-clock", h8300_div_clk_setup);