[PATCH v3] Common clock: To list active consumers of clocks

From: Vishal Badole
Date: Tue Jun 28 2022 - 01:11:26 EST


This feature lists the clock consumer's name and per-user enable count
in clock summary. Using this feature user can easily check which device
has acquired a perticular clock and it is enabled by respective device
or not.
for example:
debian@beaglebone:~$ cat /sys/kernel/debug/clk/clk_summary
enable prepare protect duty hardware per-user
clock count count count rate accuracy phase cycle enable consumer count
----------------------------------------------------------------------------------------------------------------------------
clk_mcasp0_fixed 0 0 0 24576000 0 0 50000 Y deviceless 0
deviceless 0
clk_mcasp0 0 0 0 24576000 0 0 50000 N simple-audio-card,cpu 0
deviceless 0

Co-developed-by: Chinmoy Ghosh <chinmoyghosh2001@xxxxxxxxx>
Signed-off-by: Chinmoy Ghosh <chinmoyghosh2001@xxxxxxxxx>
Co-developed-by: Mintu Patel <mintupatel89@xxxxxxxxx>
Signed-off-by: Mintu Patel <mintupatel89@xxxxxxxxx>
Co-developed-by: Vimal Kumar <vimal.kumar32@xxxxxxxxx>
Signed-off-by: Vimal Kumar <vimal.kumar32@xxxxxxxxx>
Signed-off-by: Vishal Badole <badolevishal1116@xxxxxxxxx>
---
drivers/clk/clk.c | 46 +++++++++++++++++++++++++++++++++++-----------
1 file changed, 35 insertions(+), 11 deletions(-)

diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index ed11918..6c4249e 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -102,6 +102,7 @@ struct clk {
unsigned long min_rate;
unsigned long max_rate;
unsigned int exclusive_count;
+ unsigned int enable_count;
struct hlist_node clks_node;
};

@@ -1015,6 +1016,10 @@ void clk_disable(struct clk *clk)
return;

clk_core_disable_lock(clk->core);
+
+ if (clk->enable_count > 0)
+ clk->enable_count--;
+
}
EXPORT_SYMBOL_GPL(clk_disable);

@@ -1176,10 +1181,16 @@ EXPORT_SYMBOL_GPL(clk_restore_context);
*/
int clk_enable(struct clk *clk)
{
+ int ret;
+
if (!clk)
return 0;

- return clk_core_enable_lock(clk->core);
+ ret = clk_core_enable_lock(clk->core);
+ if (!ret)
+ clk->enable_count++;
+
+ return ret;
}
EXPORT_SYMBOL_GPL(clk_enable);

@@ -2960,28 +2971,41 @@ static void clk_summary_show_one(struct seq_file *s, struct clk_core *c,
int level)
{
int phase;
+ struct clk *clk_user;
+ int multi_node = 0;

- seq_printf(s, "%*s%-*s %7d %8d %8d %11lu %10lu ",
+ seq_printf(s, "%*s%-*s %-7d %-8d %-8d %-11lu %-10lu ",
level * 3 + 1, "",
- 30 - level * 3, c->name,
+ 35 - level * 3, c->name,
c->enable_count, c->prepare_count, c->protect_count,
clk_core_get_rate_recalc(c),
clk_core_get_accuracy_recalc(c));

phase = clk_core_get_phase(c);
if (phase >= 0)
- seq_printf(s, "%5d", phase);
+ seq_printf(s, "%-5d", phase);
else
seq_puts(s, "-----");

- seq_printf(s, " %6d", clk_core_get_scaled_duty_cycle(c, 100000));
+ seq_printf(s, " %-6d", clk_core_get_scaled_duty_cycle(c, 100000));

if (c->ops->is_enabled)
- seq_printf(s, " %9c\n", clk_core_is_enabled(c) ? 'Y' : 'N');
+ seq_printf(s, " %5c ", clk_core_is_enabled(c) ? 'Y' : 'N');
else if (!c->ops->enable)
- seq_printf(s, " %9c\n", 'Y');
+ seq_printf(s, " %5c ", 'Y');
else
- seq_printf(s, " %9c\n", '?');
+ seq_printf(s, " %5c ", '?');
+
+ hlist_for_each_entry(clk_user, &c->clks, clks_node) {
+ seq_printf(s, "%*s%-*s %-4d\n",
+ level * 3 + 2 + 105 * multi_node, "",
+ 30,
+ clk_user->dev_id ? clk_user->dev_id : "deviceless",
+ clk_user->enable_count);
+
+ multi_node = 1;
+ }
+
}

static void clk_summary_show_subtree(struct seq_file *s, struct clk_core *c,
@@ -3002,9 +3026,9 @@ static int clk_summary_show(struct seq_file *s, void *data)
struct clk_core *c;
struct hlist_head **lists = (struct hlist_head **)s->private;

- seq_puts(s, " enable prepare protect duty hardware\n");
- seq_puts(s, " clock count count count rate accuracy phase cycle enable\n");
- seq_puts(s, "-------------------------------------------------------------------------------------------------------\n");
+ seq_puts(s, " enable prepare protect duty hardware per-user\n");
+ seq_puts(s, " clock count count count rate accuracy phase cycle enable consumer count\n");
+ seq_puts(s, "-------------------------------------------------------------------------------------------------------------------------------------------\n");

clk_prepare_lock();

--
2.7.4