diff options
Diffstat (limited to 'drivers/clk/clk.c')
-rw-r--r-- | drivers/clk/clk.c | 52 |
1 files changed, 49 insertions, 3 deletions
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index 95a6f5dff5cc..8a389e650032 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -637,6 +637,24 @@ static void clk_core_get_boundaries(struct clk_core *core, *max_rate = min(*max_rate, clk_user->max_rate); } +static bool clk_core_check_boundaries(struct clk_core *core, + unsigned long min_rate, + unsigned long max_rate) +{ + struct clk *user; + + lockdep_assert_held(&prepare_lock); + + if (min_rate > core->max_rate || max_rate < core->min_rate) + return false; + + hlist_for_each_entry(user, &core->clks, clks_node) + if (min_rate > user->max_rate || max_rate < user->min_rate) + return false; + + return true; +} + void clk_hw_set_rate_range(struct clk_hw *hw, unsigned long min_rate, unsigned long max_rate) { @@ -2306,6 +2324,11 @@ int clk_set_rate_range(struct clk *clk, unsigned long min, unsigned long max) clk->min_rate = min; clk->max_rate = max; + if (!clk_core_check_boundaries(clk->core, min, max)) { + ret = -EINVAL; + goto out; + } + rate = clk_core_get_rate_nolock(clk->core); if (rate < min || rate > max) { /* @@ -2334,6 +2357,7 @@ int clk_set_rate_range(struct clk *clk, unsigned long min, unsigned long max) } } +out: if (clk->exclusive_count) clk_core_rate_protect(clk->core); @@ -3279,6 +3303,19 @@ static void clk_core_reparent_orphans_nolock(void) __clk_set_parent_after(orphan, parent, NULL); __clk_recalc_accuracies(orphan); __clk_recalc_rates(orphan, 0); + + /* + * __clk_init_parent() will set the initial req_rate to + * 0 if the clock doesn't have clk_ops::recalc_rate and + * is an orphan when it's registered. + * + * 'req_rate' is used by clk_set_rate_range() and + * clk_put() to trigger a clk_set_rate() call whenever + * the boundaries are modified. Let's make sure + * 'req_rate' is set to something non-zero so that + * clk_set_rate_range() doesn't drop the frequency. + */ + orphan->req_rate = orphan->rate; } } } @@ -3300,6 +3337,14 @@ static int __clk_core_init(struct clk_core *core) clk_prepare_lock(); + /* + * Set hw->core after grabbing the prepare_lock to synchronize with + * callers of clk_core_fill_parent_index() where we treat hw->core + * being NULL as the clk not being registered yet. This is crucial so + * that clks aren't parented until their parent is fully registered. + */ + core->hw->core = core; + ret = clk_pm_runtime_get(core); if (ret) goto unlock; @@ -3453,8 +3498,10 @@ static int __clk_core_init(struct clk_core *core) out: clk_pm_runtime_put(core); unlock: - if (ret) + if (ret) { hlist_del_init(&core->child_node); + core->hw->core = NULL; + } clk_prepare_unlock(); @@ -3700,7 +3747,6 @@ __clk_register(struct device *dev, struct device_node *np, struct clk_hw *hw) core->num_parents = init->num_parents; core->min_rate = 0; core->max_rate = ULONG_MAX; - hw->core = core; ret = clk_core_populate_parent_map(core, init); if (ret) @@ -3718,7 +3764,7 @@ __clk_register(struct device *dev, struct device_node *np, struct clk_hw *hw) goto fail_create_clk; } - clk_core_link_consumer(hw->core, hw->clk); + clk_core_link_consumer(core, hw->clk); ret = __clk_core_init(core); if (!ret) |