diff options
| -rw-r--r-- | drivers/clk/clk.c | 85 | ||||
| -rw-r--r-- | include/linux/clk-private.h | 1 | ||||
| -rw-r--r-- | include/linux/clk-provider.h | 5 | ||||
| -rw-r--r-- | include/linux/clk.h | 29 |
4 files changed, 116 insertions, 4 deletions
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index b76fa69b44cb..d87661af0c72 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -117,11 +117,11 @@ static void clk_summary_show_one(struct seq_file *s, struct clk *c, int level) if (!c) return; - seq_printf(s, "%*s%-*s %11d %12d %11lu %10lu\n", + seq_printf(s, "%*s%-*s %11d %12d %11lu %10lu %-3d\n", level * 3 + 1, "", 30 - level * 3, c->name, c->enable_count, c->prepare_count, clk_get_rate(c), - clk_get_accuracy(c)); + clk_get_accuracy(c), clk_get_phase(c)); } static void clk_summary_show_subtree(struct seq_file *s, struct clk *c, @@ -143,8 +143,8 @@ static int clk_summary_show(struct seq_file *s, void *data) struct clk *c; struct hlist_head **lists = (struct hlist_head **)s->private; - seq_puts(s, " clock enable_cnt prepare_cnt rate accuracy\n"); - seq_puts(s, "--------------------------------------------------------------------------------\n"); + seq_puts(s, " clock enable_cnt prepare_cnt rate accuracy phase\n"); + seq_puts(s, "----------------------------------------------------------------------------------------\n"); clk_prepare_lock(); @@ -180,6 +180,7 @@ static void clk_dump_one(struct seq_file *s, struct clk *c, int level) seq_printf(s, "\"prepare_count\": %d,", c->prepare_count); seq_printf(s, "\"rate\": %lu", clk_get_rate(c)); seq_printf(s, "\"accuracy\": %lu", clk_get_accuracy(c)); + seq_printf(s, "\"phase\": %d", clk_get_phase(c)); } static void clk_dump_subtree(struct seq_file *s, struct clk *c, int level) @@ -264,6 +265,11 @@ static int clk_debug_create_one(struct clk *clk, struct dentry *pdentry) if (!d) goto err_out; + d = debugfs_create_u32("clk_phase", S_IRUGO, clk->dentry, + (u32 *)&clk->phase); + if (!d) + goto err_out; + d = debugfs_create_x32("clk_flags", S_IRUGO, clk->dentry, (u32 *)&clk->flags); if (!d) @@ -1739,6 +1745,77 @@ out: EXPORT_SYMBOL_GPL(clk_set_parent); /** + * clk_set_phase - adjust the phase shift of a clock signal + * @clk: clock signal source + * @degrees: number of degrees the signal is shifted + * + * Shifts the phase of a clock signal by the specified + * degrees. Returns 0 on success, -EERROR otherwise. + * + * This function makes no distinction about the input or reference + * signal that we adjust the clock signal phase against. For example + * phase locked-loop clock signal generators we may shift phase with + * respect to feedback clock signal input, but for other cases the + * clock phase may be shifted with respect to some other, unspecified + * signal. + * + * Additionally the concept of phase shift does not propagate through + * the clock tree hierarchy, which sets it apart from clock rates and + * clock accuracy. A parent clock phase attribute does not have an + * impact on the phase attribute of a child clock. + */ +int clk_set_phase(struct clk *clk, int degrees) +{ + int ret = 0; + + if (!clk) + goto out; + + /* sanity check degrees */ + degrees %= 360; + if (degrees < 0) + degrees += 360; + + clk_prepare_lock(); + + if (!clk->ops->set_phase) + goto out_unlock; + + ret = clk->ops->set_phase(clk->hw, degrees); + + if (!ret) + clk->phase = degrees; + +out_unlock: + clk_prepare_unlock(); + +out: + return ret; +} + +/** + * clk_get_phase - return the phase shift of a clock signal + * @clk: clock signal source + * + * Returns the phase shift of a clock node in degrees, otherwise returns + * -EERROR. + */ +int clk_get_phase(struct clk *clk) +{ + int ret = 0; + + if (!clk) + goto out; + + clk_prepare_lock(); + ret = clk->phase; + clk_prepare_unlock(); + +out: + return ret; +} + +/** * __clk_init - initialize the data structures in a struct clk * @dev: device initializing this clk, placeholder for now * @clk: clk being initialized diff --git a/include/linux/clk-private.h b/include/linux/clk-private.h index efbf70b9fd84..845be30be50f 100644 --- a/include/linux/clk-private.h +++ b/include/linux/clk-private.h @@ -46,6 +46,7 @@ struct clk { unsigned int enable_count; unsigned int prepare_count; unsigned long accuracy; + int phase; struct hlist_head children; struct hlist_node child_node; unsigned int notifier_count; diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h index 411dd7eb2653..201a6195a3eb 100644 --- a/include/linux/clk-provider.h +++ b/include/linux/clk-provider.h @@ -129,6 +129,10 @@ struct dentry; * set then clock accuracy will be initialized to parent accuracy * or 0 (perfect clock) if clock has no parent. * + * @set_phase: Shift the phase this clock signal in degrees specified + * by the second argument. Valid values for degrees are + * 0-359. Return 0 on success, otherwise -EERROR. + * * @init: Perform platform-specific initialization magic. * This is not not used by any of the basic clock types. * Please consider other ways of solving initialization problems @@ -177,6 +181,7 @@ struct clk_ops { unsigned long parent_rate, u8 index); unsigned long (*recalc_accuracy)(struct clk_hw *hw, unsigned long parent_accuracy); + int (*set_phase)(struct clk_hw *hw, int degrees); void (*init)(struct clk_hw *hw); int (*debug_init)(struct clk_hw *hw, struct dentry *dentry); }; diff --git a/include/linux/clk.h b/include/linux/clk.h index fb5e097d8f72..38bdedd3e389 100644 --- a/include/linux/clk.h +++ b/include/linux/clk.h @@ -106,6 +106,25 @@ int clk_notifier_unregister(struct clk *clk, struct notifier_block *nb); */ long clk_get_accuracy(struct clk *clk); +/** + * clk_set_phase - adjust the phase shift of a clock signal + * @clk: clock signal source + * @degrees: number of degrees the signal is shifted + * + * Shifts the phase of a clock signal by the specified degrees. Returns 0 on + * success, -EERROR otherwise. + */ +int clk_set_phase(struct clk *clk, int degrees); + +/** + * clk_get_phase - return the phase shift of a clock signal + * @clk: clock signal source + * + * Returns the phase shift of a clock node in degrees, otherwise returns + * -EERROR. + */ +int clk_get_phase(struct clk *clk); + #else static inline long clk_get_accuracy(struct clk *clk) @@ -113,6 +132,16 @@ static inline long clk_get_accuracy(struct clk *clk) return -ENOTSUPP; } +static inline long clk_set_phase(struct clk *clk, int phase) +{ + return -ENOTSUPP; +} + +static inline long clk_get_phase(struct clk *clk) +{ + return -ENOTSUPP; +} + #endif /** |