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authorJean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>2010-08-31 01:36:52 +0800
committerSascha Hauer <s.hauer@pengutronix.de>2010-09-20 08:56:42 +0200
commit6186a855158afcd8d97002da973d88adc8637cdd (patch)
tree3b52d17549605bfc7150a6d702a27996da87e72b /drivers/clk
parenta1ea745cb0a59d3627a3f8f2fda3ca913014cae0 (diff)
downloadbarebox-6186a855158afcd8d97002da973d88adc8637cdd.tar.gz
barebox-6186a855158afcd8d97002da973d88adc8637cdd.tar.xz
arm: move clkdev to drivers/clk
as refer in this patch "arm & sh: factorised duplicated clkdev.c" factorise some generic infrastructure to assist looking up struct clks for the ARM & SH architecture. as the code is identical at 99% in linux move it also as preparing for the SH adding Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Diffstat (limited to 'drivers/clk')
-rw-r--r--drivers/clk/Kconfig4
-rw-r--r--drivers/clk/Makefile2
-rw-r--r--drivers/clk/clkdev.c168
3 files changed, 174 insertions, 0 deletions
diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig
new file mode 100644
index 000000000..4168c8896
--- /dev/null
+++ b/drivers/clk/Kconfig
@@ -0,0 +1,4 @@
+
+config CLKDEV_LOOKUP
+ bool
+ select HAVE_CLK
diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
new file mode 100644
index 000000000..07613fa17
--- /dev/null
+++ b/drivers/clk/Makefile
@@ -0,0 +1,2 @@
+
+obj-$(CONFIG_CLKDEV_LOOKUP) += clkdev.o
diff --git a/drivers/clk/clkdev.c b/drivers/clk/clkdev.c
new file mode 100644
index 000000000..717fea568
--- /dev/null
+++ b/drivers/clk/clkdev.c
@@ -0,0 +1,168 @@
+/*
+ * drivers/clk/lookup_clkdev.c
+ *
+ * Copyright (C) 2008 Russell King.
+ *
+ * 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.
+ *
+ * Helper for the clk API to assist looking up a struct clk.
+ */
+
+#include <common.h>
+#include <linux/list.h>
+#include <errno.h>
+#include <linux/err.h>
+#include <linux/string.h>
+#include <linux/clk.h>
+#include <linux/clkdev.h>
+#include <init.h>
+#include <malloc.h>
+#include <stdio.h>
+
+static LIST_HEAD(clocks);
+
+/*
+ * Find the correct struct clk for the device and connection ID.
+ * We do slightly fuzzy matching here:
+ * An entry with a NULL ID is assumed to be a wildcard.
+ * If an entry has a device ID, it must match
+ * If an entry has a connection ID, it must match
+ * Then we take the most specific entry - with the following
+ * order of precedence: dev+con > dev only > con only.
+ */
+static struct clk *clk_find(const char *dev_id, const char *con_id)
+{
+ struct clk_lookup *p;
+ struct clk *clk = NULL;
+ int match, best = 0;
+
+ list_for_each_entry(p, &clocks, node) {
+ match = 0;
+ if (p->dev_id) {
+ if (!dev_id || strcmp(p->dev_id, dev_id))
+ continue;
+ match += 2;
+ }
+ if (p->con_id) {
+ if (!con_id || strcmp(p->con_id, con_id))
+ continue;
+ match += 1;
+ }
+
+ if (match > best) {
+ clk = p->clk;
+ if (match != 3)
+ best = match;
+ else
+ break;
+ }
+ }
+ return clk;
+}
+
+struct clk *clk_get_sys(const char *dev_id, const char *con_id)
+{
+ struct clk *clk;
+
+ clk = clk_find(dev_id, con_id);
+ if (clk && !__clk_get(clk))
+ clk = NULL;
+
+ return clk ? clk : ERR_PTR(-ENOENT);
+}
+EXPORT_SYMBOL(clk_get_sys);
+
+struct clk *clk_get(struct device_d *dev, const char *con_id)
+{
+ const char *dev_id = dev ? dev_name(dev) : NULL;
+
+ return clk_get_sys(dev_id, con_id);
+}
+EXPORT_SYMBOL(clk_get);
+
+void clk_put(struct clk *clk)
+{
+ __clk_put(clk);
+}
+EXPORT_SYMBOL(clk_put);
+
+void clkdev_add(struct clk_lookup *cl)
+{
+ list_add_tail(&cl->node, &clocks);
+}
+EXPORT_SYMBOL(clkdev_add);
+
+void __init clkdev_add_table(struct clk_lookup *cl, size_t num)
+{
+ while (num--) {
+ list_add_tail(&cl->node, &clocks);
+ cl++;
+ }
+}
+
+#define MAX_DEV_ID 20
+#define MAX_CON_ID 16
+
+struct clk_lookup_alloc {
+ struct clk_lookup cl;
+ char dev_id[MAX_DEV_ID];
+ char con_id[MAX_CON_ID];
+};
+
+struct clk_lookup *clkdev_alloc(struct clk *clk, const char *con_id,
+ const char *dev_fmt, ...)
+{
+ struct clk_lookup_alloc *cla;
+
+ cla = kzalloc(sizeof(*cla), GFP_KERNEL);
+ if (!cla)
+ return NULL;
+
+ cla->cl.clk = clk;
+ if (con_id) {
+ strlcpy(cla->con_id, con_id, sizeof(cla->con_id));
+ cla->cl.con_id = cla->con_id;
+ }
+
+ if (dev_fmt) {
+ va_list ap;
+
+ va_start(ap, dev_fmt);
+ vscnprintf(cla->dev_id, sizeof(cla->dev_id), dev_fmt, ap);
+ cla->cl.dev_id = cla->dev_id;
+ va_end(ap);
+ }
+
+ return &cla->cl;
+}
+EXPORT_SYMBOL(clkdev_alloc);
+
+int clk_add_alias(const char *alias, const char *alias_dev_name, char *id,
+ struct device_d *dev)
+{
+ struct clk *r = clk_get(dev, id);
+ struct clk_lookup *l;
+
+ if (IS_ERR(r))
+ return PTR_ERR(r);
+
+ l = clkdev_alloc(r, alias, alias_dev_name);
+ clk_put(r);
+ if (!l)
+ return -ENODEV;
+ clkdev_add(l);
+ return 0;
+}
+EXPORT_SYMBOL(clk_add_alias);
+
+/*
+ * clkdev_drop - remove a clock dynamically allocated
+ */
+void clkdev_drop(struct clk_lookup *cl)
+{
+ list_del(&cl->node);
+ kfree(cl);
+}
+EXPORT_SYMBOL(clkdev_drop);