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author | 2015-08-04 12:17:53 -0700 | |
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committer | 2015-08-04 15:44:42 -0700 | |
commit | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch) | |
tree | 1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/drivers/clk/clkdev.c | |
parent | 98260f3884f4a202f9ca5eabed40b1354c489b29 (diff) |
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base.
It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:
commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Sat Jul 25 12:13:34 2015 +0200
Prepare v4.1.3-rt3
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.
Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/drivers/clk/clkdev.c')
-rw-r--r-- | kernel/drivers/clk/clkdev.c | 374 |
1 files changed, 374 insertions, 0 deletions
diff --git a/kernel/drivers/clk/clkdev.c b/kernel/drivers/clk/clkdev.c new file mode 100644 index 000000000..1fcb6ef2c --- /dev/null +++ b/kernel/drivers/clk/clkdev.c @@ -0,0 +1,374 @@ +/* + * drivers/clk/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 <linux/clk.h> +#include <linux/clkdev.h> +#include <linux/clk-provider.h> +#include <linux/of.h> + +#include "clk.h" + +static LIST_HEAD(clocks); +static DEFINE_MUTEX(clocks_mutex); + +#if defined(CONFIG_OF) && defined(CONFIG_COMMON_CLK) +static struct clk *__of_clk_get(struct device_node *np, int index, + const char *dev_id, const char *con_id) +{ + struct of_phandle_args clkspec; + struct clk *clk; + int rc; + + if (index < 0) + return ERR_PTR(-EINVAL); + + rc = of_parse_phandle_with_args(np, "clocks", "#clock-cells", index, + &clkspec); + if (rc) + return ERR_PTR(rc); + + clk = __of_clk_get_from_provider(&clkspec, dev_id, con_id); + of_node_put(clkspec.np); + + return clk; +} + +struct clk *of_clk_get(struct device_node *np, int index) +{ + return __of_clk_get(np, index, np->full_name, NULL); +} +EXPORT_SYMBOL(of_clk_get); + +static struct clk *__of_clk_get_by_name(struct device_node *np, + const char *dev_id, + const char *name) +{ + struct clk *clk = ERR_PTR(-ENOENT); + + /* Walk up the tree of devices looking for a clock that matches */ + while (np) { + int index = 0; + + /* + * For named clocks, first look up the name in the + * "clock-names" property. If it cannot be found, then + * index will be an error code, and of_clk_get() will fail. + */ + if (name) + index = of_property_match_string(np, "clock-names", name); + clk = __of_clk_get(np, index, dev_id, name); + if (!IS_ERR(clk)) { + break; + } else if (name && index >= 0) { + if (PTR_ERR(clk) != -EPROBE_DEFER) + pr_err("ERROR: could not get clock %s:%s(%i)\n", + np->full_name, name ? name : "", index); + return clk; + } + + /* + * No matching clock found on this node. If the parent node + * has a "clock-ranges" property, then we can try one of its + * clocks. + */ + np = np->parent; + if (np && !of_get_property(np, "clock-ranges", NULL)) + break; + } + + return clk; +} + +/** + * of_clk_get_by_name() - Parse and lookup a clock referenced by a device node + * @np: pointer to clock consumer node + * @name: name of consumer's clock input, or NULL for the first clock reference + * + * This function parses the clocks and clock-names properties, + * and uses them to look up the struct clk from the registered list of clock + * providers. + */ +struct clk *of_clk_get_by_name(struct device_node *np, const char *name) +{ + if (!np) + return ERR_PTR(-ENOENT); + + return __of_clk_get_by_name(np, np->full_name, name); +} +EXPORT_SYMBOL(of_clk_get_by_name); + +#else /* defined(CONFIG_OF) && defined(CONFIG_COMMON_CLK) */ + +static struct clk *__of_clk_get_by_name(struct device_node *np, + const char *dev_id, + const char *name) +{ + return ERR_PTR(-ENOENT); +} +#endif + +/* + * 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_lookup *clk_find(const char *dev_id, const char *con_id) +{ + struct clk_lookup *p, *cl = NULL; + int match, best_found = 0, best_possible = 0; + + if (dev_id) + best_possible += 2; + if (con_id) + best_possible += 1; + + 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_found) { + cl = p; + if (match != best_possible) + best_found = match; + else + break; + } + } + return cl; +} + +struct clk *clk_get_sys(const char *dev_id, const char *con_id) +{ + struct clk_lookup *cl; + struct clk *clk = NULL; + + mutex_lock(&clocks_mutex); + + cl = clk_find(dev_id, con_id); + if (!cl) + goto out; + + clk = __clk_create_clk(__clk_get_hw(cl->clk), dev_id, con_id); + if (IS_ERR(clk)) + goto out; + + if (!__clk_get(clk)) { + __clk_free_clk(clk); + cl = NULL; + goto out; + } + +out: + mutex_unlock(&clocks_mutex); + + return cl ? clk : ERR_PTR(-ENOENT); +} +EXPORT_SYMBOL(clk_get_sys); + +struct clk *clk_get(struct device *dev, const char *con_id) +{ + const char *dev_id = dev ? dev_name(dev) : NULL; + struct clk *clk; + + if (dev) { + clk = __of_clk_get_by_name(dev->of_node, dev_id, con_id); + if (!IS_ERR(clk) || PTR_ERR(clk) == -EPROBE_DEFER) + return clk; + } + + 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) +{ + mutex_lock(&clocks_mutex); + list_add_tail(&cl->node, &clocks); + mutex_unlock(&clocks_mutex); +} +EXPORT_SYMBOL(clkdev_add); + +void __init clkdev_add_table(struct clk_lookup *cl, size_t num) +{ + mutex_lock(&clocks_mutex); + while (num--) { + list_add_tail(&cl->node, &clocks); + cl++; + } + mutex_unlock(&clocks_mutex); +} + +#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]; +}; + +static struct clk_lookup * __init_refok +vclkdev_alloc(struct clk *clk, const char *con_id, const char *dev_fmt, + va_list ap) +{ + struct clk_lookup_alloc *cla; + + cla = __clkdev_alloc(sizeof(*cla)); + 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) { + vscnprintf(cla->dev_id, sizeof(cla->dev_id), dev_fmt, ap); + cla->cl.dev_id = cla->dev_id; + } + + return &cla->cl; +} + +struct clk_lookup * __init_refok +clkdev_alloc(struct clk *clk, const char *con_id, const char *dev_fmt, ...) +{ + struct clk_lookup *cl; + va_list ap; + + va_start(ap, dev_fmt); + cl = vclkdev_alloc(clk, con_id, dev_fmt, ap); + va_end(ap); + + return cl; +} +EXPORT_SYMBOL(clkdev_alloc); + +int clk_add_alias(const char *alias, const char *alias_dev_name, char *id, + struct device *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) +{ + mutex_lock(&clocks_mutex); + list_del(&cl->node); + mutex_unlock(&clocks_mutex); + kfree(cl); +} +EXPORT_SYMBOL(clkdev_drop); + +/** + * clk_register_clkdev - register one clock lookup for a struct clk + * @clk: struct clk to associate with all clk_lookups + * @con_id: connection ID string on device + * @dev_id: format string describing device name + * + * con_id or dev_id may be NULL as a wildcard, just as in the rest of + * clkdev. + * + * To make things easier for mass registration, we detect error clks + * from a previous clk_register() call, and return the error code for + * those. This is to permit this function to be called immediately + * after clk_register(). + */ +int clk_register_clkdev(struct clk *clk, const char *con_id, + const char *dev_fmt, ...) +{ + struct clk_lookup *cl; + va_list ap; + + if (IS_ERR(clk)) + return PTR_ERR(clk); + + va_start(ap, dev_fmt); + cl = vclkdev_alloc(clk, con_id, dev_fmt, ap); + va_end(ap); + + if (!cl) + return -ENOMEM; + + clkdev_add(cl); + + return 0; +} +EXPORT_SYMBOL(clk_register_clkdev); + +/** + * clk_register_clkdevs - register a set of clk_lookup for a struct clk + * @clk: struct clk to associate with all clk_lookups + * @cl: array of clk_lookup structures with con_id and dev_id pre-initialized + * @num: number of clk_lookup structures to register + * + * To make things easier for mass registration, we detect error clks + * from a previous clk_register() call, and return the error code for + * those. This is to permit this function to be called immediately + * after clk_register(). + */ +int clk_register_clkdevs(struct clk *clk, struct clk_lookup *cl, size_t num) +{ + unsigned i; + + if (IS_ERR(clk)) + return PTR_ERR(clk); + + for (i = 0; i < num; i++, cl++) { + cl->clk = clk; + clkdev_add(cl); + } + + return 0; +} +EXPORT_SYMBOL(clk_register_clkdevs); |