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Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419// SPDX-License-Identifier: GPL-2.0-only/* * drivers/clk/clkdev.c * * Copyright (C) 2008 Russell King. * * 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);
/* * 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;
lockdep_assert_held(&clocks_mutex);
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_hw *clk_find_hw(const char *dev_id, const char *con_id){ struct clk_lookup *cl; struct clk_hw *hw = ERR_PTR(-ENOENT);
mutex_lock(&clocks_mutex); cl = clk_find(dev_id, con_id); if (cl) hw = cl->clk_hw; mutex_unlock(&clocks_mutex);
return hw;}
static struct clk *__clk_get_sys(struct device *dev, const char *dev_id, const char *con_id){ struct clk_hw *hw = clk_find_hw(dev_id, con_id);
return clk_hw_create_clk(dev, hw, dev_id, con_id);}
struct clk *clk_get_sys(const char *dev_id, const char *con_id){ return __clk_get_sys(NULL, dev_id, con_id);}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_hw *hw;
if (dev && dev->of_node) { hw = of_clk_get_hw(dev->of_node, 0, con_id); if (!IS_ERR(hw) || PTR_ERR(hw) == -EPROBE_DEFER) return clk_hw_create_clk(dev, hw, dev_id, con_id); }
return __clk_get_sys(dev, dev_id, con_id);}EXPORT_SYMBOL(clk_get);
void clk_put(struct clk *clk){ __clk_put(clk);}EXPORT_SYMBOL(clk_put);
static void __clkdev_add(struct clk_lookup *cl){ mutex_lock(&clocks_mutex); list_add_tail(&cl->node, &clocks); mutex_unlock(&clocks_mutex);}
void clkdev_add(struct clk_lookup *cl){ if (!cl->clk_hw) cl->clk_hw = __clk_get_hw(cl->clk); __clkdev_add(cl);}EXPORT_SYMBOL(clkdev_add);
void clkdev_add_table(struct clk_lookup *cl, size_t num){ mutex_lock(&clocks_mutex); while (num--) { cl->clk_hw = __clk_get_hw(cl->clk); list_add_tail(&cl->node, &clocks); cl++; } mutex_unlock(&clocks_mutex);}
#define MAX_DEV_ID 24#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 __printf(3, 0) struct clk_lookup * __refvclkdev_alloc(struct clk_hw *hw, const char *con_id, const char *dev_fmt, va_list ap){ struct clk_lookup_alloc *cla; struct va_format vaf; const char *failure; va_list ap_copy; size_t max_size; ssize_t res;
cla = kzalloc_obj(*cla); if (!cla) return NULL;
va_copy(ap_copy, ap);
cla->cl.clk_hw = hw; if (con_id) { res = strscpy(cla->con_id, con_id, sizeof(cla->con_id)); if (res < 0) { max_size = sizeof(cla->con_id); failure = "connection"; goto fail; } cla->cl.con_id = cla->con_id; }
if (dev_fmt) { res = vsnprintf(cla->dev_id, sizeof(cla->dev_id), dev_fmt, ap); if (res >= sizeof(cla->dev_id)) { max_size = sizeof(cla->dev_id); failure = "device"; goto fail; } cla->cl.dev_id = cla->dev_id; }
va_end(ap_copy);
return &cla->cl;
fail: if (dev_fmt) vaf.fmt = dev_fmt; else vaf.fmt = "null-device"; vaf.va = &ap_copy; pr_err("%pV:%s: %s ID is greater than %zu\n", &vaf, con_id, failure, max_size); va_end(ap_copy);
/* * Don't fail in this case, but as the entry won't ever match just * fill it with something that also won't match. */ strscpy(cla->con_id, "bad", sizeof(cla->con_id)); strscpy(cla->dev_id, "bad", sizeof(cla->dev_id));
return &cla->cl;}
static __printf(3, 0) struct clk_lookup *vclkdev_create(struct clk_hw *hw, const char *con_id, const char *dev_fmt, va_list ap){ struct clk_lookup *cl;
cl = vclkdev_alloc(hw, con_id, dev_fmt, ap); if (cl) __clkdev_add(cl);
return cl;}
/** * clkdev_create - allocate and add a clkdev lookup structure * @clk: struct clk to associate with all clk_lookups * @con_id: connection ID string on device * @dev_fmt: format string describing device name * * Returns a clk_lookup structure, which can be later unregistered and * freed. */struct clk_lookup *clkdev_create(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_create(__clk_get_hw(clk), con_id, dev_fmt, ap); va_end(ap);
return cl;}EXPORT_SYMBOL_GPL(clkdev_create);
/** * clkdev_hw_create - allocate and add a clkdev lookup structure * @hw: struct clk_hw to associate with all clk_lookups * @con_id: connection ID string on device * @dev_fmt: format string describing device name * * Returns a clk_lookup structure, which can be later unregistered and * freed. */struct clk_lookup *clkdev_hw_create(struct clk_hw *hw, const char *con_id, const char *dev_fmt, ...){ struct clk_lookup *cl; va_list ap;
va_start(ap, dev_fmt); cl = vclkdev_create(hw, con_id, dev_fmt, ap); va_end(ap);
return cl;}EXPORT_SYMBOL_GPL(clkdev_hw_create);
int clk_add_alias(const char *alias, const char *alias_dev_name, const char *con_id, struct device *dev){ struct clk *r = clk_get(dev, con_id); struct clk_lookup *l;
if (IS_ERR(r)) return PTR_ERR(r);
l = clkdev_create(r, alias, alias_dev_name ? "%s" : NULL, alias_dev_name); clk_put(r);
return l ? 0 : -ENODEV;}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);
static __printf(3, 4) struct clk_lookup *__clk_register_clkdev(struct clk_hw *hw, const char *con_id, const char *dev_id, ...){ struct clk_lookup *cl; va_list ap;
va_start(ap, dev_id); cl = vclkdev_create(hw, con_id, dev_id, ap); va_end(ap);
return cl;}
static int do_clk_register_clkdev(struct clk_hw *hw, struct clk_lookup **cl, const char *con_id, const char *dev_id){ if (IS_ERR(hw)) return PTR_ERR(hw); /* * Since dev_id can be NULL, and NULL is handled specially, we must * pass it as either a NULL format string, or with "%s". */ if (dev_id) *cl = __clk_register_clkdev(hw, con_id, "%s", dev_id); else *cl = __clk_register_clkdev(hw, con_id, NULL);
return *cl ? 0 : -ENOMEM;}
/** * 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: 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_id){ struct clk_lookup *cl;
if (IS_ERR(clk)) return PTR_ERR(clk);
return do_clk_register_clkdev(__clk_get_hw(clk), &cl, con_id, dev_id);}EXPORT_SYMBOL(clk_register_clkdev);
/** * clk_hw_register_clkdev - register one clock lookup for a struct clk_hw * @hw: struct clk_hw 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 clk_hws * from a previous clk_hw_register_*() call, and return the error code for * those. This is to permit this function to be called immediately * after clk_hw_register_*(). */int clk_hw_register_clkdev(struct clk_hw *hw, const char *con_id, const char *dev_id){ struct clk_lookup *cl;
return do_clk_register_clkdev(hw, &cl, con_id, dev_id);}EXPORT_SYMBOL(clk_hw_register_clkdev);
static void devm_clkdev_release(void *res){ clkdev_drop(res);}
/** * devm_clk_hw_register_clkdev - managed clk lookup registration for clk_hw * @dev: device this lookup is bound * @hw: struct clk_hw 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 clk_hws * from a previous clk_hw_register_*() call, and return the error code for * those. This is to permit this function to be called immediately * after clk_hw_register_*(). */int devm_clk_hw_register_clkdev(struct device *dev, struct clk_hw *hw, const char *con_id, const char *dev_id){ struct clk_lookup *cl; int rval;
rval = do_clk_register_clkdev(hw, &cl, con_id, dev_id); if (rval) return rval;
return devm_add_action_or_reset(dev, devm_clkdev_release, cl);}EXPORT_SYMBOL(devm_clk_hw_register_clkdev);