diff options
Diffstat (limited to 'drivers/clk/clk.c')
-rw-r--r-- | drivers/clk/clk.c | 142 |
1 files changed, 104 insertions, 38 deletions
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index 9c5b9419e585..d529ad67805c 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -3285,6 +3285,34 @@ static inline void clk_debug_unregister(struct clk_core *core) } #endif +static void clk_core_reparent_orphans_nolock(void) +{ + struct clk_core *orphan; + struct hlist_node *tmp2; + + /* + * walk the list of orphan clocks and reparent any that newly finds a + * parent. + */ + hlist_for_each_entry_safe(orphan, tmp2, &clk_orphan_list, child_node) { + struct clk_core *parent = __clk_init_parent(orphan); + + /* + * We need to use __clk_set_parent_before() and _after() to + * to properly migrate any prepare/enable count of the orphan + * clock. This is important for CLK_IS_CRITICAL clocks, which + * are enabled during init but might not have a parent yet. + */ + if (parent) { + /* update the clk tree topology */ + __clk_set_parent_before(orphan, parent); + __clk_set_parent_after(orphan, parent, NULL); + __clk_recalc_accuracies(orphan); + __clk_recalc_rates(orphan, 0); + } + } +} + /** * __clk_core_init - initialize the data structures in a struct clk_core * @core: clk_core being initialized @@ -3295,8 +3323,6 @@ static inline void clk_debug_unregister(struct clk_core *core) static int __clk_core_init(struct clk_core *core) { int ret; - struct clk_core *orphan; - struct hlist_node *tmp2; unsigned long rate; if (!core) @@ -3348,6 +3374,26 @@ static int __clk_core_init(struct clk_core *core) goto out; } + /* + * optional platform-specific magic + * + * The .init callback is not used by any of the basic clock types, but + * exists for weird hardware that must perform initialization magic for + * CCF to get an accurate view of clock for any other callbacks. It may + * also be used needs to perform dynamic allocations. Such allocation + * must be freed in the terminate() callback. + * This callback shall not be used to initialize the parameters state, + * such as rate, parent, etc ... + * + * If it exist, this callback should called before any other callback of + * the clock + */ + if (core->ops->init) { + ret = core->ops->init(core->hw); + if (ret) + goto out; + } + core->parent = __clk_init_parent(core); /* @@ -3373,17 +3419,6 @@ static int __clk_core_init(struct clk_core *core) } /* - * optional platform-specific magic - * - * The .init callback is not used by any of the basic clock types, but - * exists for weird hardware that must perform initialization magic. - * Please consider other ways of solving initialization problems before - * using this callback, as its use is discouraged. - */ - if (core->ops->init) - core->ops->init(core->hw); - - /* * Set clk's accuracy. The preferred method is to use * .recalc_accuracy. For simple clocks and lazy developers the default * fallback is to use the parent's accuracy. If a clock doesn't have a @@ -3436,34 +3471,26 @@ static int __clk_core_init(struct clk_core *core) if (core->flags & CLK_IS_CRITICAL) { unsigned long flags; - clk_core_prepare(core); + ret = clk_core_prepare(core); + if (ret) { + pr_warn("%s: critical clk '%s' failed to prepare\n", + __func__, core->name); + goto out; + } flags = clk_enable_lock(); - clk_core_enable(core); + ret = clk_core_enable(core); clk_enable_unlock(flags); + if (ret) { + pr_warn("%s: critical clk '%s' failed to enable\n", + __func__, core->name); + clk_core_unprepare(core); + goto out; + } } - /* - * walk the list of orphan clocks and reparent any that newly finds a - * parent. - */ - hlist_for_each_entry_safe(orphan, tmp2, &clk_orphan_list, child_node) { - struct clk_core *parent = __clk_init_parent(orphan); + clk_core_reparent_orphans_nolock(); - /* - * We need to use __clk_set_parent_before() and _after() to - * to properly migrate any prepare/enable count of the orphan - * clock. This is important for CLK_IS_CRITICAL clocks, which - * are enabled during init but might not have a parent yet. - */ - if (parent) { - /* update the clk tree topology */ - __clk_set_parent_before(orphan, parent); - __clk_set_parent_after(orphan, parent, NULL); - __clk_recalc_accuracies(orphan); - __clk_recalc_rates(orphan, 0); - } - } kref_init(&core->ref); out: @@ -3756,6 +3783,28 @@ fail_out: } /** + * dev_or_parent_of_node() - Get device node of @dev or @dev's parent + * @dev: Device to get device node of + * + * Return: device node pointer of @dev, or the device node pointer of + * @dev->parent if dev doesn't have a device node, or NULL if neither + * @dev or @dev->parent have a device node. + */ +static struct device_node *dev_or_parent_of_node(struct device *dev) +{ + struct device_node *np; + + if (!dev) + return NULL; + + np = dev_of_node(dev); + if (!np) + np = dev_of_node(dev->parent); + + return np; +} + +/** * 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 @@ -3770,7 +3819,7 @@ fail_out: */ struct clk *clk_register(struct device *dev, struct clk_hw *hw) { - return __clk_register(dev, dev_of_node(dev), hw); + return __clk_register(dev, dev_or_parent_of_node(dev), hw); } EXPORT_SYMBOL_GPL(clk_register); @@ -3786,7 +3835,8 @@ EXPORT_SYMBOL_GPL(clk_register); */ int clk_hw_register(struct device *dev, struct clk_hw *hw) { - return PTR_ERR_OR_ZERO(__clk_register(dev, dev_of_node(dev), hw)); + return PTR_ERR_OR_ZERO(__clk_register(dev, dev_or_parent_of_node(dev), + hw)); } EXPORT_SYMBOL_GPL(clk_hw_register); @@ -3889,6 +3939,7 @@ static void clk_core_evict_parent_cache(struct clk_core *core) void clk_unregister(struct clk *clk) { unsigned long flags; + const struct clk_ops *ops; if (!clk || WARN_ON_ONCE(IS_ERR(clk))) return; @@ -3897,7 +3948,8 @@ void clk_unregister(struct clk *clk) clk_prepare_lock(); - if (clk->core->ops == &clk_nodrv_ops) { + ops = clk->core->ops; + if (ops == &clk_nodrv_ops) { pr_err("%s: unregistered clock: %s\n", __func__, clk->core->name); goto unlock; @@ -3910,6 +3962,9 @@ void clk_unregister(struct clk *clk) clk->core->ops = &clk_nodrv_ops; clk_enable_unlock(flags); + if (ops->terminate) + ops->terminate(clk->core->hw); + if (!hlist_empty(&clk->core->children)) { struct clk_core *child; struct hlist_node *t; @@ -4215,6 +4270,13 @@ int clk_notifier_unregister(struct clk *clk, struct notifier_block *nb) EXPORT_SYMBOL_GPL(clk_notifier_unregister); #ifdef CONFIG_OF +static void clk_core_reparent_orphans(void) +{ + clk_prepare_lock(); + clk_core_reparent_orphans_nolock(); + clk_prepare_unlock(); +} + /** * struct of_clk_provider - Clock provider registration structure * @link: Entry in global list of clock providers @@ -4310,6 +4372,8 @@ int of_clk_add_provider(struct device_node *np, mutex_unlock(&of_clk_mutex); pr_debug("Added clock from %pOF\n", np); + clk_core_reparent_orphans(); + ret = of_clk_set_defaults(np, true); if (ret < 0) of_clk_del_provider(np); @@ -4345,6 +4409,8 @@ int of_clk_add_hw_provider(struct device_node *np, mutex_unlock(&of_clk_mutex); pr_debug("Added clk_hw provider from %pOF\n", np); + clk_core_reparent_orphans(); + ret = of_clk_set_defaults(np, true); if (ret < 0) of_clk_del_provider(np); |