From: Stephen Boyd Date: Mon, 24 Sep 2012 20:38:04 +0000 (-0700) Subject: clk: Add devm_clk_{register,unregister}() X-Git-Tag: firefly_0821_release~3680^2~1528^2~37 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=46c8773a58010d31f228e148b8b774d94cc9810d;p=firefly-linux-kernel-4.4.55.git clk: Add devm_clk_{register,unregister}() Some clock drivers can be simplified if devres takes care of unregistering any registered clocks along error paths. Introduce devm_clk_register() so that clock drivers get unregistration for free along with simplified error paths. Signed-off-by: Stephen Boyd Signed-off-by: Mike Turquette --- diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index bbe52c4ae7ca..2fd28ddd06c9 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -17,6 +17,7 @@ #include #include #include +#include static DEFINE_SPINLOCK(enable_lock); static DEFINE_MUTEX(prepare_lock); @@ -1361,28 +1362,9 @@ struct clk *__clk_register(struct device *dev, struct clk_hw *hw) } EXPORT_SYMBOL_GPL(__clk_register); -/** - * clk_register - allocate a new clock, register it and return an opaque cookie - * @dev: device that is registering this clock - * @hw: link to hardware-specific clock data - * - * clk_register is the primary interface for populating the clock tree with new - * clock nodes. It returns a pointer to the newly allocated struct clk which - * cannot be dereferenced by driver code but may be used in conjuction with the - * rest of the clock API. In the event of an error clk_register will return an - * error code; drivers must test for an error code after calling clk_register. - */ -struct clk *clk_register(struct device *dev, struct clk_hw *hw) +static int _clk_register(struct device *dev, struct clk_hw *hw, struct clk *clk) { int i, ret; - struct clk *clk; - - clk = kzalloc(sizeof(*clk), GFP_KERNEL); - if (!clk) { - pr_err("%s: could not allocate clk\n", __func__); - ret = -ENOMEM; - goto fail_out; - } clk->name = kstrdup(hw->init->name, GFP_KERNEL); if (!clk->name) { @@ -1420,7 +1402,7 @@ struct clk *clk_register(struct device *dev, struct clk_hw *hw) ret = __clk_init(dev, clk); if (!ret) - return clk; + return 0; fail_parent_names_copy: while (--i >= 0) @@ -1429,6 +1411,36 @@ fail_parent_names_copy: fail_parent_names: kfree(clk->name); fail_name: + return ret; +} + +/** + * clk_register - allocate a new clock, register it and return an opaque cookie + * @dev: device that is registering this clock + * @hw: link to hardware-specific clock data + * + * clk_register is the primary interface for populating the clock tree with new + * clock nodes. It returns a pointer to the newly allocated struct clk which + * cannot be dereferenced by driver code but may be used in conjuction with the + * rest of the clock API. In the event of an error clk_register will return an + * error code; drivers must test for an error code after calling clk_register. + */ +struct clk *clk_register(struct device *dev, struct clk_hw *hw) +{ + int ret; + struct clk *clk; + + clk = kzalloc(sizeof(*clk), GFP_KERNEL); + if (!clk) { + pr_err("%s: could not allocate clk\n", __func__); + ret = -ENOMEM; + goto fail_out; + } + + ret = _clk_register(dev, hw, clk); + if (!ret) + return clk; + kfree(clk); fail_out: return ERR_PTR(ret); @@ -1444,6 +1456,63 @@ EXPORT_SYMBOL_GPL(clk_register); void clk_unregister(struct clk *clk) {} EXPORT_SYMBOL_GPL(clk_unregister); +static void devm_clk_release(struct device *dev, void *res) +{ + clk_unregister(res); +} + +/** + * devm_clk_register - resource managed clk_register() + * @dev: device that is registering this clock + * @hw: link to hardware-specific clock data + * + * Managed clk_register(). Clocks returned from this function are + * automatically clk_unregister()ed on driver detach. See clk_register() for + * more information. + */ +struct clk *devm_clk_register(struct device *dev, struct clk_hw *hw) +{ + struct clk *clk; + int ret; + + clk = devres_alloc(devm_clk_release, sizeof(*clk), GFP_KERNEL); + if (!clk) + return ERR_PTR(-ENOMEM); + + ret = _clk_register(dev, hw, clk); + if (!ret) { + devres_add(dev, clk); + } else { + devres_free(clk); + clk = ERR_PTR(ret); + } + + return clk; +} +EXPORT_SYMBOL_GPL(devm_clk_register); + +static int devm_clk_match(struct device *dev, void *res, void *data) +{ + struct clk *c = res; + if (WARN_ON(!c)) + return 0; + return c == data; +} + +/** + * devm_clk_unregister - resource managed clk_unregister() + * @clk: clock to unregister + * + * Deallocate a clock allocated with devm_clk_register(). Normally + * this function will not need to be called and the resource management + * code will ensure that the resource is freed. + */ +void devm_clk_unregister(struct device *dev, struct clk *clk) +{ + WARN_ON(devres_release(dev, devm_clk_release, devm_clk_match, clk)); +} +EXPORT_SYMBOL_GPL(devm_clk_unregister); + /*** clk rate change notifiers ***/ /** diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h index 0dce3d31eae5..3593a3ce3f0d 100644 --- a/include/linux/clk-provider.h +++ b/include/linux/clk-provider.h @@ -331,8 +331,10 @@ struct clk *clk_register_fixed_factor(struct device *dev, const char *name, * error code; drivers must test for an error code after calling clk_register. */ struct clk *clk_register(struct device *dev, struct clk_hw *hw); +struct clk *devm_clk_register(struct device *dev, struct clk_hw *hw); void clk_unregister(struct clk *clk); +void devm_clk_unregister(struct device *dev, struct clk *clk); /* helper functions */ const char *__clk_get_name(struct clk *clk);