Merge tag 'clk-core-duty-cycle-for-mark' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux into asoc-4.19
Duty cycle support for the clk api and drivers.
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 9760b52..b0a2719 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -68,6 +68,7 @@
unsigned long max_rate;
unsigned long accuracy;
int phase;
+ struct clk_duty duty;
struct hlist_head children;
struct hlist_node child_node;
struct hlist_head clks;
@@ -2402,6 +2403,172 @@
}
EXPORT_SYMBOL_GPL(clk_get_phase);
+static void clk_core_reset_duty_cycle_nolock(struct clk_core *core)
+{
+ /* Assume a default value of 50% */
+ core->duty.num = 1;
+ core->duty.den = 2;
+}
+
+static int clk_core_update_duty_cycle_parent_nolock(struct clk_core *core);
+
+static int clk_core_update_duty_cycle_nolock(struct clk_core *core)
+{
+ struct clk_duty *duty = &core->duty;
+ int ret = 0;
+
+ if (!core->ops->get_duty_cycle)
+ return clk_core_update_duty_cycle_parent_nolock(core);
+
+ ret = core->ops->get_duty_cycle(core->hw, duty);
+ if (ret)
+ goto reset;
+
+ /* Don't trust the clock provider too much */
+ if (duty->den == 0 || duty->num > duty->den) {
+ ret = -EINVAL;
+ goto reset;
+ }
+
+ return 0;
+
+reset:
+ clk_core_reset_duty_cycle_nolock(core);
+ return ret;
+}
+
+static int clk_core_update_duty_cycle_parent_nolock(struct clk_core *core)
+{
+ int ret = 0;
+
+ if (core->parent &&
+ core->flags & CLK_DUTY_CYCLE_PARENT) {
+ ret = clk_core_update_duty_cycle_nolock(core->parent);
+ memcpy(&core->duty, &core->parent->duty, sizeof(core->duty));
+ } else {
+ clk_core_reset_duty_cycle_nolock(core);
+ }
+
+ return ret;
+}
+
+static int clk_core_set_duty_cycle_parent_nolock(struct clk_core *core,
+ struct clk_duty *duty);
+
+static int clk_core_set_duty_cycle_nolock(struct clk_core *core,
+ struct clk_duty *duty)
+{
+ int ret;
+
+ lockdep_assert_held(&prepare_lock);
+
+ if (clk_core_rate_is_protected(core))
+ return -EBUSY;
+
+ trace_clk_set_duty_cycle(core, duty);
+
+ if (!core->ops->set_duty_cycle)
+ return clk_core_set_duty_cycle_parent_nolock(core, duty);
+
+ ret = core->ops->set_duty_cycle(core->hw, duty);
+ if (!ret)
+ memcpy(&core->duty, duty, sizeof(*duty));
+
+ trace_clk_set_duty_cycle_complete(core, duty);
+
+ return ret;
+}
+
+static int clk_core_set_duty_cycle_parent_nolock(struct clk_core *core,
+ struct clk_duty *duty)
+{
+ int ret = 0;
+
+ if (core->parent &&
+ core->flags & (CLK_DUTY_CYCLE_PARENT | CLK_SET_RATE_PARENT)) {
+ ret = clk_core_set_duty_cycle_nolock(core->parent, duty);
+ memcpy(&core->duty, &core->parent->duty, sizeof(core->duty));
+ }
+
+ return ret;
+}
+
+/**
+ * clk_set_duty_cycle - adjust the duty cycle ratio of a clock signal
+ * @clk: clock signal source
+ * @num: numerator of the duty cycle ratio to be applied
+ * @den: denominator of the duty cycle ratio to be applied
+ *
+ * Apply the duty cycle ratio if the ratio is valid and the clock can
+ * perform this operation
+ *
+ * Returns (0) on success, a negative errno otherwise.
+ */
+int clk_set_duty_cycle(struct clk *clk, unsigned int num, unsigned int den)
+{
+ int ret;
+ struct clk_duty duty;
+
+ if (!clk)
+ return 0;
+
+ /* sanity check the ratio */
+ if (den == 0 || num > den)
+ return -EINVAL;
+
+ duty.num = num;
+ duty.den = den;
+
+ clk_prepare_lock();
+
+ if (clk->exclusive_count)
+ clk_core_rate_unprotect(clk->core);
+
+ ret = clk_core_set_duty_cycle_nolock(clk->core, &duty);
+
+ if (clk->exclusive_count)
+ clk_core_rate_protect(clk->core);
+
+ clk_prepare_unlock();
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(clk_set_duty_cycle);
+
+static int clk_core_get_scaled_duty_cycle(struct clk_core *core,
+ unsigned int scale)
+{
+ struct clk_duty *duty = &core->duty;
+ int ret;
+
+ clk_prepare_lock();
+
+ ret = clk_core_update_duty_cycle_nolock(core);
+ if (!ret)
+ ret = mult_frac(scale, duty->num, duty->den);
+
+ clk_prepare_unlock();
+
+ return ret;
+}
+
+/**
+ * clk_get_scaled_duty_cycle - return the duty cycle ratio of a clock signal
+ * @clk: clock signal source
+ * @scale: scaling factor to be applied to represent the ratio as an integer
+ *
+ * Returns the duty cycle ratio of a clock node multiplied by the provided
+ * scaling factor, or negative errno on error.
+ */
+int clk_get_scaled_duty_cycle(struct clk *clk, unsigned int scale)
+{
+ if (!clk)
+ return 0;
+
+ return clk_core_get_scaled_duty_cycle(clk->core, scale);
+}
+EXPORT_SYMBOL_GPL(clk_get_scaled_duty_cycle);
+
/**
* clk_is_match - check if two clk's point to the same hardware clock
* @p: clk compared against q
@@ -2455,12 +2622,13 @@
if (!c)
return;
- seq_printf(s, "%*s%-*s %7d %8d %8d %11lu %10lu %-3d\n",
+ seq_printf(s, "%*s%-*s %7d %8d %8d %11lu %10lu %5d %6d\n",
level * 3 + 1, "",
30 - level * 3, c->name,
c->enable_count, c->prepare_count, c->protect_count,
clk_core_get_rate(c), clk_core_get_accuracy(c),
- clk_core_get_phase(c));
+ clk_core_get_phase(c),
+ clk_core_get_scaled_duty_cycle(c, 100000));
}
static void clk_summary_show_subtree(struct seq_file *s, struct clk_core *c,
@@ -2482,9 +2650,9 @@
struct clk_core *c;
struct hlist_head **lists = (struct hlist_head **)s->private;
- seq_puts(s, " enable prepare protect \n");
- seq_puts(s, " clock count count count rate accuracy phase\n");
- seq_puts(s, "----------------------------------------------------------------------------------------\n");
+ seq_puts(s, " enable prepare protect duty\n");
+ seq_puts(s, " clock count count count rate accuracy phase cycle\n");
+ seq_puts(s, "---------------------------------------------------------------------------------------------\n");
clk_prepare_lock();
@@ -2511,6 +2679,8 @@
seq_printf(s, "\"rate\": %lu,", clk_core_get_rate(c));
seq_printf(s, "\"accuracy\": %lu,", clk_core_get_accuracy(c));
seq_printf(s, "\"phase\": %d", clk_core_get_phase(c));
+ seq_printf(s, "\"duty_cycle\": %u",
+ clk_core_get_scaled_duty_cycle(c, 100000));
}
static void clk_dump_subtree(struct seq_file *s, struct clk_core *c, int level)
@@ -2572,6 +2742,7 @@
ENTRY(CLK_SET_RATE_UNGATE),
ENTRY(CLK_IS_CRITICAL),
ENTRY(CLK_OPS_PARENT_ENABLE),
+ ENTRY(CLK_DUTY_CYCLE_PARENT),
#undef ENTRY
};
@@ -2610,6 +2781,17 @@
}
DEFINE_SHOW_ATTRIBUTE(possible_parents);
+static int clk_duty_cycle_show(struct seq_file *s, void *data)
+{
+ struct clk_core *core = s->private;
+ struct clk_duty *duty = &core->duty;
+
+ seq_printf(s, "%u/%u\n", duty->num, duty->den);
+
+ return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(clk_duty_cycle);
+
static void clk_debug_create_one(struct clk_core *core, struct dentry *pdentry)
{
struct dentry *root;
@@ -2628,6 +2810,8 @@
debugfs_create_u32("clk_enable_count", 0444, root, &core->enable_count);
debugfs_create_u32("clk_protect_count", 0444, root, &core->protect_count);
debugfs_create_u32("clk_notifier_count", 0444, root, &core->notifier_count);
+ debugfs_create_file("clk_duty_cycle", 0444, root, core,
+ &clk_duty_cycle_fops);
if (core->num_parents > 1)
debugfs_create_file("clk_possible_parents", 0444, root, core,
@@ -2846,6 +3030,11 @@
core->phase = 0;
/*
+ * Set clk's duty cycle.
+ */
+ clk_core_update_duty_cycle_nolock(core);
+
+ /*
* Set clk's rate. The preferred method is to use .recalc_rate. For
* simple clocks and lazy developers the default fallback is to use the
* parent's rate. If a clock doesn't have a parent (or is orphaned)
diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h
index b7cfa03..08b1aa7 100644
--- a/include/linux/clk-provider.h
+++ b/include/linux/clk-provider.h
@@ -38,6 +38,8 @@
#define CLK_IS_CRITICAL BIT(11) /* do not gate, ever */
/* parents need enable during gate/ungate, set rate and re-parent */
#define CLK_OPS_PARENT_ENABLE BIT(12)
+/* duty cycle call may be forwarded to the parent clock */
+#define CLK_DUTY_CYCLE_PARENT BIT(13)
struct clk;
struct clk_hw;
@@ -67,6 +69,17 @@
};
/**
+ * struct clk_duty - Struture encoding the duty cycle ratio of a clock
+ *
+ * @num: Numerator of the duty cycle ratio
+ * @den: Denominator of the duty cycle ratio
+ */
+struct clk_duty {
+ unsigned int num;
+ unsigned int den;
+};
+
+/**
* struct clk_ops - Callback operations for hardware clocks; these are to
* be provided by the clock implementation, and will be called by drivers
* through the clk_* api.
@@ -169,6 +182,15 @@
* by the second argument. Valid values for degrees are
* 0-359. Return 0 on success, otherwise -EERROR.
*
+ * @get_duty_cycle: Queries the hardware to get the current duty cycle ratio
+ * of a clock. Returned values denominator cannot be 0 and must be
+ * superior or equal to the numerator.
+ *
+ * @set_duty_cycle: Apply the duty cycle ratio to this clock signal specified by
+ * the numerator (2nd argurment) and denominator (3rd argument).
+ * Argument must be a valid ratio (denominator > 0
+ * and >= numerator) 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
@@ -218,6 +240,10 @@
unsigned long parent_accuracy);
int (*get_phase)(struct clk_hw *hw);
int (*set_phase)(struct clk_hw *hw, int degrees);
+ int (*get_duty_cycle)(struct clk_hw *hw,
+ struct clk_duty *duty);
+ int (*set_duty_cycle)(struct clk_hw *hw,
+ struct clk_duty *duty);
void (*init)(struct clk_hw *hw);
void (*debug_init)(struct clk_hw *hw, struct dentry *dentry);
};
diff --git a/include/linux/clk.h b/include/linux/clk.h
index 0dbd088..4f750c4 100644
--- a/include/linux/clk.h
+++ b/include/linux/clk.h
@@ -142,6 +142,27 @@
int clk_get_phase(struct clk *clk);
/**
+ * clk_set_duty_cycle - adjust the duty cycle ratio of a clock signal
+ * @clk: clock signal source
+ * @num: numerator of the duty cycle ratio to be applied
+ * @den: denominator of the duty cycle ratio to be applied
+ *
+ * Adjust the duty cycle of a clock signal by the specified ratio. Returns 0 on
+ * success, -EERROR otherwise.
+ */
+int clk_set_duty_cycle(struct clk *clk, unsigned int num, unsigned int den);
+
+/**
+ * clk_get_duty_cycle - return the duty cycle ratio of a clock signal
+ * @clk: clock signal source
+ * @scale: scaling factor to be applied to represent the ratio as an integer
+ *
+ * Returns the duty cycle ratio multiplied by the scale provided, otherwise
+ * returns -EERROR.
+ */
+int clk_get_scaled_duty_cycle(struct clk *clk, unsigned int scale);
+
+/**
* clk_is_match - check if two clk's point to the same hardware clock
* @p: clk compared against q
* @q: clk compared against p
@@ -183,6 +204,18 @@
return -ENOTSUPP;
}
+static inline int clk_set_duty_cycle(struct clk *clk, unsigned int num,
+ unsigned int den)
+{
+ return -ENOTSUPP;
+}
+
+static inline unsigned int clk_get_scaled_duty_cycle(struct clk *clk,
+ unsigned int scale)
+{
+ return 0;
+}
+
static inline bool clk_is_match(const struct clk *p, const struct clk *q)
{
return p == q;
diff --git a/include/trace/events/clk.h b/include/trace/events/clk.h
index 2cd4493..9004fff 100644
--- a/include/trace/events/clk.h
+++ b/include/trace/events/clk.h
@@ -192,6 +192,42 @@
TP_ARGS(core, phase)
);
+DECLARE_EVENT_CLASS(clk_duty_cycle,
+
+ TP_PROTO(struct clk_core *core, struct clk_duty *duty),
+
+ TP_ARGS(core, duty),
+
+ TP_STRUCT__entry(
+ __string( name, core->name )
+ __field( unsigned int, num )
+ __field( unsigned int, den )
+ ),
+
+ TP_fast_assign(
+ __assign_str(name, core->name);
+ __entry->num = duty->num;
+ __entry->den = duty->den;
+ ),
+
+ TP_printk("%s %u/%u", __get_str(name), (unsigned int)__entry->num,
+ (unsigned int)__entry->den)
+);
+
+DEFINE_EVENT(clk_duty_cycle, clk_set_duty_cycle,
+
+ TP_PROTO(struct clk_core *core, struct clk_duty *duty),
+
+ TP_ARGS(core, duty)
+);
+
+DEFINE_EVENT(clk_duty_cycle, clk_set_duty_cycle_complete,
+
+ TP_PROTO(struct clk_core *core, struct clk_duty *duty),
+
+ TP_ARGS(core, duty)
+);
+
#endif /* _TRACE_CLK_H */
/* This part must be outside protection */