diff options
author | Russell King <rmk@dyn-67.arm.linux.org.uk> | 2008-11-09 16:32:46 +0000 |
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committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2008-11-27 12:38:21 +0000 |
commit | 0318e693d3a56836632bf1a2cfdafb7f34bcc703 (patch) | |
tree | f31f9e227681b4a9251381442384aca20e59f840 /arch | |
parent | ed313489badef16d700f5a3be50e8fd8f8294bc8 (diff) | |
download | op-kernel-dev-0318e693d3a56836632bf1a2cfdafb7f34bcc703.zip op-kernel-dev-0318e693d3a56836632bf1a2cfdafb7f34bcc703.tar.gz |
[ARM] clkdev: add generic clkdev infrastructure
Add some generic infrastructure to assist looking up struct clks
for the ARM architecture.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch')
-rw-r--r-- | arch/arm/common/Kconfig | 3 | ||||
-rw-r--r-- | arch/arm/common/Makefile | 1 | ||||
-rw-r--r-- | arch/arm/common/clkdev.c | 128 | ||||
-rw-r--r-- | arch/arm/include/asm/clkdev.h | 30 |
4 files changed, 162 insertions, 0 deletions
diff --git a/arch/arm/common/Kconfig b/arch/arm/common/Kconfig index 86b5e69..a2cd9be 100644 --- a/arch/arm/common/Kconfig +++ b/arch/arm/common/Kconfig @@ -33,3 +33,6 @@ config SHARPSL_PM config SHARP_SCOOP bool + +config COMMON_CLKDEV + bool diff --git a/arch/arm/common/Makefile b/arch/arm/common/Makefile index 325e4b6..7cb7961 100644 --- a/arch/arm/common/Makefile +++ b/arch/arm/common/Makefile @@ -17,3 +17,4 @@ obj-$(CONFIG_SHARP_SCOOP) += scoop.o obj-$(CONFIG_ARCH_IXP2000) += uengine.o obj-$(CONFIG_ARCH_IXP23XX) += uengine.o obj-$(CONFIG_PCI_HOST_ITE8152) += it8152.o +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..17a17b4 --- /dev/null +++ b/arch/arm/common/clkdev.c @@ -0,0 +1,128 @@ +/* + * 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 <linux/module.h> +#include <linux/kernel.h> +#include <linux/device.h> +#include <linux/list.h> +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/string.h> +#include <linux/mutex.h> + +#include <asm/clkdev.h> +#include <mach/clkdev.h> + +static LIST_HEAD(clocks); +static DEFINE_MUTEX(clocks_mutex); + +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) { + if ((p->dev_id && !dev_id) || (p->con_id && !con_id)) + continue; + match = 0; + if (p->dev_id) + match += 2 * (strcmp(p->dev_id, dev_id) == 0); + if (p->con_id) + match += 1 * (strcmp(p->con_id, con_id) == 0); + if (match == 0) + continue; + + if (match > best) { + clk = p->clk; + best = match; + } + } + return clk; +} + +struct clk *clk_get(struct device *dev, const char *con_id) +{ + const char *dev_id = dev ? dev_name(dev) : NULL; + struct clk *clk; + + mutex_lock(&clocks_mutex); + clk = clk_find(dev_id, con_id); + if (clk && !__clk_get(clk)) + clk = NULL; + mutex_unlock(&clocks_mutex); + + return clk ? clk : ERR_PTR(-ENOENT); +} +EXPORT_SYMBOL(clk_get); + +void clk_put(struct clk *clk) +{ + __clk_put(clk); +} +EXPORT_SYMBOL(clk_put); + +void clkdev_add(struct clk_lookup *cl) +{ + mutex_lock(&clocks_mutex); + list_add_tail(&cl->node, &clocks); + mutex_unlock(&clocks_mutex); +} +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); + +/* + * clkdev_drop - remove a clock dynamically allocated + */ +void clkdev_drop(struct clk_lookup *cl) +{ + mutex_lock(&clocks_mutex); + list_del(&cl->node); + mutex_unlock(&clocks_mutex); + 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 |