diff options
Diffstat (limited to 'drivers/clk/clk.c')
| -rw-r--r-- | drivers/clk/clk.c | 222 |
1 files changed, 218 insertions, 4 deletions
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index fb74dc1f7520..d584004f7af7 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -574,6 +574,9 @@ static void clk_core_unprepare(struct clk_core *core) if (WARN_ON(core->prepare_count == 0)) return; + if (WARN_ON(core->prepare_count == 1 && core->flags & CLK_IS_CRITICAL)) + return; + if (--core->prepare_count > 0) return; @@ -679,6 +682,9 @@ static void clk_core_disable(struct clk_core *core) if (WARN_ON(core->enable_count == 0)) return; + if (WARN_ON(core->enable_count == 1 && core->flags & CLK_IS_CRITICAL)) + return; + if (--core->enable_count > 0) return; @@ -2397,6 +2403,16 @@ static int __clk_core_init(struct clk_core *core) if (core->ops->init) core->ops->init(core->hw); + if (core->flags & CLK_IS_CRITICAL) { + unsigned long flags; + + clk_core_prepare(core); + + flags = clk_enable_lock(); + clk_core_enable(core); + clk_enable_unlock(flags); + } + kref_init(&core->ref); out: clk_prepare_unlock(); @@ -2536,6 +2552,22 @@ fail_out: } EXPORT_SYMBOL_GPL(clk_register); +/** + * clk_hw_register - register a clk_hw and return an error code + * @dev: device that is registering this clock + * @hw: link to hardware-specific clock data + * + * clk_hw_register is the primary interface for populating the clock tree with + * new clock nodes. It returns an integer equal to zero indicating success or + * less than zero indicating failure. Drivers must test for an error code after + * calling clk_hw_register(). + */ +int clk_hw_register(struct device *dev, struct clk_hw *hw) +{ + return PTR_ERR_OR_ZERO(clk_register(dev, hw)); +} +EXPORT_SYMBOL_GPL(clk_hw_register); + /* Free memory allocated for a clock. */ static void __clk_release(struct kref *ref) { @@ -2637,11 +2669,26 @@ unlock: } EXPORT_SYMBOL_GPL(clk_unregister); +/** + * clk_hw_unregister - unregister a currently registered clk_hw + * @hw: hardware-specific clock data to unregister + */ +void clk_hw_unregister(struct clk_hw *hw) +{ + clk_unregister(hw->clk); +} +EXPORT_SYMBOL_GPL(clk_hw_unregister); + static void devm_clk_release(struct device *dev, void *res) { clk_unregister(*(struct clk **)res); } +static void devm_clk_hw_release(struct device *dev, void *res) +{ + clk_hw_unregister(*(struct clk_hw **)res); +} + /** * devm_clk_register - resource managed clk_register() * @dev: device that is registering this clock @@ -2672,6 +2719,36 @@ struct clk *devm_clk_register(struct device *dev, struct clk_hw *hw) } EXPORT_SYMBOL_GPL(devm_clk_register); +/** + * devm_clk_hw_register - resource managed clk_hw_register() + * @dev: device that is registering this clock + * @hw: link to hardware-specific clock data + * + * Managed clk_hw_register(). Clocks registered by this function are + * automatically clk_hw_unregister()ed on driver detach. See clk_hw_register() + * for more information. + */ +int devm_clk_hw_register(struct device *dev, struct clk_hw *hw) +{ + struct clk_hw **hwp; + int ret; + + hwp = devres_alloc(devm_clk_hw_release, sizeof(*hwp), GFP_KERNEL); + if (!hwp) + return -ENOMEM; + + ret = clk_hw_register(dev, hw); + if (!ret) { + *hwp = hw; + devres_add(dev, hwp); + } else { + devres_free(hwp); + } + + return ret; +} +EXPORT_SYMBOL_GPL(devm_clk_hw_register); + static int devm_clk_match(struct device *dev, void *res, void *data) { struct clk *c = res; @@ -2680,6 +2757,15 @@ static int devm_clk_match(struct device *dev, void *res, void *data) return c == data; } +static int devm_clk_hw_match(struct device *dev, void *res, void *data) +{ + struct clk_hw *hw = res; + + if (WARN_ON(!hw)) + return 0; + return hw == data; +} + /** * devm_clk_unregister - resource managed clk_unregister() * @clk: clock to unregister @@ -2694,6 +2780,22 @@ void devm_clk_unregister(struct device *dev, struct clk *clk) } EXPORT_SYMBOL_GPL(devm_clk_unregister); +/** + * devm_clk_hw_unregister - resource managed clk_hw_unregister() + * @dev: device that is unregistering the hardware-specific clock data + * @hw: link to hardware-specific clock data + * + * Unregister a clk_hw registered with devm_clk_hw_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_hw_unregister(struct device *dev, struct clk_hw *hw) +{ + WARN_ON(devres_release(dev, devm_clk_hw_release, devm_clk_hw_match, + hw)); +} +EXPORT_SYMBOL_GPL(devm_clk_hw_unregister); + /* * clkdev helpers */ @@ -2855,6 +2957,7 @@ struct of_clk_provider { struct device_node *node; struct clk *(*get)(struct of_phandle_args *clkspec, void *data); + struct clk_hw *(*get_hw)(struct of_phandle_args *clkspec, void *data); void *data; }; @@ -2871,6 +2974,12 @@ struct clk *of_clk_src_simple_get(struct of_phandle_args *clkspec, } EXPORT_SYMBOL_GPL(of_clk_src_simple_get); +struct clk_hw *of_clk_hw_simple_get(struct of_phandle_args *clkspec, void *data) +{ + return data; +} +EXPORT_SYMBOL_GPL(of_clk_hw_simple_get); + struct clk *of_clk_src_onecell_get(struct of_phandle_args *clkspec, void *data) { struct clk_onecell_data *clk_data = data; @@ -2885,6 +2994,21 @@ struct clk *of_clk_src_onecell_get(struct of_phandle_args *clkspec, void *data) } EXPORT_SYMBOL_GPL(of_clk_src_onecell_get); +struct clk_hw * +of_clk_hw_onecell_get(struct of_phandle_args *clkspec, void *data) +{ + struct clk_hw_onecell_data *hw_data = data; + unsigned int idx = clkspec->args[0]; + + if (idx >= hw_data->num) { + pr_err("%s: invalid index %u\n", __func__, idx); + return ERR_PTR(-EINVAL); + } + + return hw_data->hws[idx]; +} +EXPORT_SYMBOL_GPL(of_clk_hw_onecell_get); + /** * of_clk_add_provider() - Register a clock provider for a node * @np: Device node pointer associated with clock provider @@ -2921,6 +3045,41 @@ int of_clk_add_provider(struct device_node *np, EXPORT_SYMBOL_GPL(of_clk_add_provider); /** + * of_clk_add_hw_provider() - Register a clock provider for a node + * @np: Device node pointer associated with clock provider + * @get: callback for decoding clk_hw + * @data: context pointer for @get callback. + */ +int of_clk_add_hw_provider(struct device_node *np, + struct clk_hw *(*get)(struct of_phandle_args *clkspec, + void *data), + void *data) +{ + struct of_clk_provider *cp; + int ret; + + cp = kzalloc(sizeof(*cp), GFP_KERNEL); + if (!cp) + return -ENOMEM; + + cp->node = of_node_get(np); + cp->data = data; + cp->get_hw = get; + + mutex_lock(&of_clk_mutex); + list_add(&cp->link, &of_clk_providers); + mutex_unlock(&of_clk_mutex); + pr_debug("Added clk_hw provider from %s\n", np->full_name); + + ret = of_clk_set_defaults(np, true); + if (ret < 0) + of_clk_del_provider(np); + + return ret; +} +EXPORT_SYMBOL_GPL(of_clk_add_hw_provider); + +/** * of_clk_del_provider() - Remove a previously registered clock provider * @np: Device node pointer associated with clock provider */ @@ -2941,11 +3100,32 @@ void of_clk_del_provider(struct device_node *np) } EXPORT_SYMBOL_GPL(of_clk_del_provider); +static struct clk_hw * +__of_clk_get_hw_from_provider(struct of_clk_provider *provider, + struct of_phandle_args *clkspec) +{ + struct clk *clk; + struct clk_hw *hw = ERR_PTR(-EPROBE_DEFER); + + if (provider->get_hw) { + hw = provider->get_hw(clkspec, provider->data); + } else if (provider->get) { + clk = provider->get(clkspec, provider->data); + if (!IS_ERR(clk)) + hw = __clk_get_hw(clk); + else + hw = ERR_CAST(clk); + } + + return hw; +} + struct clk *__of_clk_get_from_provider(struct of_phandle_args *clkspec, const char *dev_id, const char *con_id) { struct of_clk_provider *provider; struct clk *clk = ERR_PTR(-EPROBE_DEFER); + struct clk_hw *hw = ERR_PTR(-EPROBE_DEFER); if (!clkspec) return ERR_PTR(-EINVAL); @@ -2954,10 +3134,9 @@ struct clk *__of_clk_get_from_provider(struct of_phandle_args *clkspec, mutex_lock(&of_clk_mutex); list_for_each_entry(provider, &of_clk_providers, link) { if (provider->node == clkspec->np) - clk = provider->get(clkspec, provider->data); - if (!IS_ERR(clk)) { - clk = __clk_create_clk(__clk_get_hw(clk), dev_id, - con_id); + hw = __of_clk_get_hw_from_provider(provider, clkspec); + if (!IS_ERR(hw)) { + clk = __clk_create_clk(hw, dev_id, con_id); if (!IS_ERR(clk) && !__clk_get(clk)) { __clk_free_clk(clk); @@ -3127,6 +3306,41 @@ static int parent_ready(struct device_node *np) } /** + * of_clk_detect_critical() - set CLK_IS_CRITICAL flag from Device Tree + * @np: Device node pointer associated with clock provider + * @index: clock index + * @flags: pointer to clk_core->flags + * + * Detects if the clock-critical property exists and, if so, sets the + * corresponding CLK_IS_CRITICAL flag. + * + * Do not use this function. It exists only for legacy Device Tree + * bindings, such as the one-clock-per-node style that are outdated. + * Those bindings typically put all clock data into .dts and the Linux + * driver has no clock data, thus making it impossible to set this flag + * correctly from the driver. Only those drivers may call + * of_clk_detect_critical from their setup functions. + * + * Return: error code or zero on success + */ +int of_clk_detect_critical(struct device_node *np, + int index, unsigned long *flags) +{ + struct property *prop; + const __be32 *cur; + uint32_t idx; + + if (!np || !flags) + return -EINVAL; + + of_property_for_each_u32(np, "clock-critical", prop, cur, idx) + if (index == idx) + *flags |= CLK_IS_CRITICAL; + + return 0; +} + +/** * of_clk_init() - Scan and init clock providers from the DT * @matches: array of compatible values and init functions for providers. * |