[PATCH 2/6] arm: add common clkdev
Jean-Christophe PLAGNIOL-VILLARD
plagnioj at jcrosoft.com
Tue Aug 3 21:43:55 EDT 2010
Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj at jcrosoft.com>
Cc: Andrea GALLO <andrea.gallo at stericsson.com>
Cc: Gael SALLES <gael.salles at stericsson.com>
---
arch/arm/Kconfig | 1 +
arch/arm/Makefile | 2 +-
arch/arm/common/Kconfig | 2 +
arch/arm/common/Makefile | 5 ++
arch/arm/common/clkdev.c | 160 +++++++++++++++++++++++++++++++++++++++++
arch/arm/include/asm/clkdev.h | 30 ++++++++
lib/vsprintf.c | 25 +++++++
7 files changed, 224 insertions(+), 1 deletions(-)
create mode 100644 arch/arm/common/Kconfig
create mode 100644 arch/arm/common/Makefile
create mode 100644 arch/arm/common/clkdev.c
create mode 100644 arch/arm/include/asm/clkdev.h
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 92ec417..ed05a89 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -53,6 +53,7 @@ config ARCH_S3C24xx
endchoice
+source arch/arm/common/Kconfig
source arch/arm/cpu/Kconfig
source arch/arm/mach-at91/Kconfig
source arch/arm/mach-at91rm9200/Kconfig
diff --git a/arch/arm/Makefile b/arch/arm/Makefile
index 8b4d64c..bd78259 100644
--- a/arch/arm/Makefile
+++ b/arch/arm/Makefile
@@ -130,7 +130,7 @@ MACH :=
endif
common-y += $(BOARD) $(MACH)
-common-y += arch/arm/lib/ arch/arm/cpu/
+common-y += arch/arm/lib/ arch/arm/cpu/ arch/arm/common/
lds-$(CONFIG_GENERIC_LINKER_SCRIPT) := arch/arm/lib/barebox.lds
lds-$(CONFIG_BOARD_LINKER_SCRIPT) := $(BOARD)/barebox.lds
diff --git a/arch/arm/common/Kconfig b/arch/arm/common/Kconfig
new file mode 100644
index 0000000..e749e45
--- /dev/null
+++ b/arch/arm/common/Kconfig
@@ -0,0 +1,2 @@
+config COMMON_CLKDEV
+ bool
diff --git a/arch/arm/common/Makefile b/arch/arm/common/Makefile
new file mode 100644
index 0000000..9cc8834
--- /dev/null
+++ b/arch/arm/common/Makefile
@@ -0,0 +1,5 @@
+#
+# Makefile for the linux kernel.
+#
+
+obj-$(CONFIG_COMMON_CLKDEV) += clkdev.o
diff --git a/arch/arm/common/clkdev.c b/arch/arm/common/clkdev.c
new file mode 100644
index 0000000..4d25356
--- /dev/null
+++ b/arch/arm/common/clkdev.c
@@ -0,0 +1,160 @@
+/*
+ * arch/arm/common/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/clk.h>
+#include <init.h>
+#include <malloc.h>
+#include <stdio.h>
+
+#include <asm/clkdev.h>
+#include <mach/clkdev.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 precidence: 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 == 0)
+ continue;
+
+ if (match > best) {
+ clk = p->clk;
+ best = match;
+ }
+ }
+ 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);
+
+#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);
diff --git a/arch/arm/include/asm/clkdev.h b/arch/arm/include/asm/clkdev.h
new file mode 100644
index 0000000..b6ec7c6
--- /dev/null
+++ b/arch/arm/include/asm/clkdev.h
@@ -0,0 +1,30 @@
+/*
+ * arch/arm/include/asm/clkdev.h
+ *
+ * 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.
+ */
+#ifndef __ASM_CLKDEV_H
+#define __ASM_CLKDEV_H
+
+struct clk;
+
+struct clk_lookup {
+ struct list_head node;
+ const char *dev_id;
+ const char *con_id;
+ struct clk *clk;
+};
+
+struct clk_lookup *clkdev_alloc(struct clk *clk, const char *con_id,
+ const char *dev_fmt, ...);
+
+void clkdev_add(struct clk_lookup *cl);
+void clkdev_drop(struct clk_lookup *cl);
+
+#endif
diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index 91ad613..6066845 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -515,6 +515,31 @@ int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
EXPORT_SYMBOL(vsnprintf);
/**
+ * vscnprintf - Format a string and place it in a buffer
+ * @buf: The buffer to place the result into
+ * @size: The size of the buffer, including the trailing null space
+ * @fmt: The format string to use
+ * @args: Arguments for the format string
+ *
+ * The return value is the number of characters which have been written into
+ * the @buf not including the trailing '\0'. If @size is <= 0 the function
+ * returns 0.
+ *
+ * Call this function if you are already dealing with a va_list.
+ * You probably want scnprintf() instead.
+ *
+ * See the vsnprintf() documentation for format string extensions over C99.
+ */
+int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
+{
+ int i;
+
+ i=vsnprintf(buf,size,fmt,args);
+ return (i >= size) ? (size - 1) : i;
+}
+EXPORT_SYMBOL(vscnprintf);
+
+/**
* vsprintf - Format a string and place it in a buffer
* @buf: The buffer to place the result into
* @fmt: The format string to use
--
1.7.1
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