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-rw-r--r--drivers/clk/clk-conf.c148
1 files changed, 148 insertions, 0 deletions
diff --git a/drivers/clk/clk-conf.c b/drivers/clk/clk-conf.c
new file mode 100644
index 000000000..93271b4f9
--- /dev/null
+++ b/drivers/clk/clk-conf.c
@@ -0,0 +1,148 @@
+/*
+ * Copyright (C) 2014 Samsung Electronics Co., Ltd.
+ * Sylwester Nawrocki <s.nawrocki@samsung.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.
+ */
+
+#include <common.h>
+#include <io.h>
+#include <malloc.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/clk/clk-conf.h>
+
+#if defined(CONFIG_OFTREE) && defined(CONFIG_COMMON_CLK_OF_PROVIDER)
+
+static int __set_clk_parents(struct device_node *node, bool clk_supplier)
+{
+ struct of_phandle_args clkspec;
+ int index, rc, num_parents;
+ struct clk *clk, *pclk;
+
+ num_parents = of_count_phandle_with_args(node, "assigned-clock-parents",
+ "#clock-cells");
+ if (num_parents == -EINVAL)
+ pr_err("clk: invalid value of clock-parents property at %s\n",
+ node->full_name);
+
+ for (index = 0; index < num_parents; index++) {
+ rc = of_parse_phandle_with_args(node, "assigned-clock-parents",
+ "#clock-cells", index, &clkspec);
+ if (rc < 0) {
+ /* skip empty (null) phandles */
+ if (rc == -ENOENT)
+ continue;
+ else
+ return rc;
+ }
+ if (clkspec.np == node && !clk_supplier)
+ return 0;
+ pclk = of_clk_get_from_provider(&clkspec);
+ if (IS_ERR(pclk)) {
+ pr_warn("clk: couldn't get parent clock %d for %s\n",
+ index, node->full_name);
+ return PTR_ERR(pclk);
+ }
+
+ rc = of_parse_phandle_with_args(node, "assigned-clocks",
+ "#clock-cells", index, &clkspec);
+ if (rc < 0)
+ goto err;
+ if (clkspec.np == node && !clk_supplier) {
+ rc = 0;
+ goto err;
+ }
+ clk = of_clk_get_from_provider(&clkspec);
+ if (IS_ERR(clk)) {
+ pr_warn("clk: couldn't get parent clock %d for %s\n",
+ index, node->full_name);
+ rc = PTR_ERR(clk);
+ goto err;
+ }
+
+ rc = clk_set_parent(clk, pclk);
+ if (rc < 0)
+ pr_err("clk: failed to reparent %s to %s: %d\n",
+ __clk_get_name(clk), __clk_get_name(pclk), rc);
+ clk_put(clk);
+ clk_put(pclk);
+ }
+ return 0;
+err:
+ clk_put(pclk);
+ return rc;
+}
+
+static int __set_clk_rates(struct device_node *node, bool clk_supplier)
+{
+ struct of_phandle_args clkspec;
+ struct property *prop;
+ const __be32 *cur;
+ int rc, index = 0;
+ struct clk *clk;
+ u32 rate;
+
+ of_property_for_each_u32(node, "assigned-clock-rates", prop, cur, rate) {
+ if (rate) {
+ rc = of_parse_phandle_with_args(node, "assigned-clocks",
+ "#clock-cells", index, &clkspec);
+ if (rc < 0) {
+ /* skip empty (null) phandles */
+ if (rc == -ENOENT)
+ continue;
+ else
+ return rc;
+ }
+ if (clkspec.np == node && !clk_supplier)
+ return 0;
+
+ clk = of_clk_get_from_provider(&clkspec);
+ if (IS_ERR(clk)) {
+ pr_warn("clk: couldn't get clock %d for %s\n",
+ index, node->full_name);
+ return PTR_ERR(clk);
+ }
+
+ rc = clk_set_rate(clk, rate);
+ if (rc < 0)
+ pr_err("clk: couldn't set %s clk rate to %d (%d), current rate: %ld\n",
+ __clk_get_name(clk), rate, rc,
+ clk_get_rate(clk));
+ clk_put(clk);
+ }
+ index++;
+ }
+ return 0;
+}
+
+/**
+ * of_clk_set_defaults() - parse and set assigned clocks configuration
+ * @node: device node to apply clock settings for
+ * @clk_supplier: true if clocks supplied by @node should also be considered
+ *
+ * This function parses 'assigned-{clocks/clock-parents/clock-rates}' properties
+ * and sets any specified clock parents and rates. The @clk_supplier argument
+ * should be set to true if @node may be also a clock supplier of any clock
+ * listed in its 'assigned-clocks' or 'assigned-clock-parents' properties.
+ * If @clk_supplier is false the function exits returning 0 as soon as it
+ * determines the @node is also a supplier of any of the clocks.
+ */
+int of_clk_set_defaults(struct device_node *node, bool clk_supplier)
+{
+ int rc;
+
+ if (!node)
+ return 0;
+
+ rc = __set_clk_parents(node, clk_supplier);
+ if (rc < 0)
+ return rc;
+
+ return __set_clk_rates(node, clk_supplier);
+}
+EXPORT_SYMBOL_GPL(of_clk_set_defaults);
+
+#endif