[PATCH] clk: Add clk_min/max_rate entries in debugfs

[PATCH] clk: Add clk_min/max_rate entries in debugfs

[Leonard Crestez]

Add two files to expose min/max clk rates as determined by
clk_core_get_boundaries, taking all consumer requests into account.

This information does not appear to be otherwise exposed to userspace.

Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
---
 drivers/clk/clk.c | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index fbf63daa62bc..a51d8ffb2d40 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -3031,10 +3031,34 @@ static int clk_duty_cycle_show(struct seq_file *s, void *data)
 
 	return 0;
 }
 DEFINE_SHOW_ATTRIBUTE(clk_duty_cycle);
 
+static int clk_min_rate_show(struct seq_file *s, void *data)
+{
+	struct clk_core *core = s->private;
+	unsigned long min_rate, max_rate;
+
+	clk_core_get_boundaries(core, &min_rate, &max_rate);
+	seq_printf(s, "%lu\n", min_rate);
+
+	return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(clk_min_rate);
+
+static int clk_max_rate_show(struct seq_file *s, void *data)
+{
+	struct clk_core *core = s->private;
+	unsigned long min_rate, max_rate;
+
+	clk_core_get_boundaries(core, &min_rate, &max_rate);
+	seq_printf(s, "%lu\n", max_rate);
+
+	return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(clk_max_rate);
+
 static void clk_debug_create_one(struct clk_core *core, struct dentry *pdentry)
 {
 	struct dentry *root;
 
 	if (!core || !pdentry)
@@ -3042,10 +3066,12 @@ static void clk_debug_create_one(struct clk_core *core, struct dentry *pdentry)
 
 	root = debugfs_create_dir(core->name, pdentry);
 	core->dentry = root;
 
 	debugfs_create_ulong("clk_rate", 0444, root, &core->rate);
+	debugfs_create_file("clk_min_rate", 0444, root, core, &clk_min_rate_fops);
+	debugfs_create_file("clk_max_rate", 0444, root, core, &clk_max_rate_fops);
 	debugfs_create_ulong("clk_accuracy", 0444, root, &core->accuracy);
 	debugfs_create_u32("clk_phase", 0444, root, &core->phase);
 	debugfs_create_file("clk_flags", 0444, root, core, &clk_flags_fops);
 	debugfs_create_u32("clk_prepare_count", 0444, root, &core->prepare_count);
 	debugfs_create_u32("clk_enable_count", 0444, root, &core->enable_count);
-- 
2.17.1

Re: [PATCH] clk: Add clk_min/max_rate entries in debugfs

[Geert Uytterhoeven]

Hi Leonard,

On Thu, Jun 27, 2019 at 5:22 PM Leonard Crestez <leonard.crestez@nxp.com> wrote:
> Add two files to expose min/max clk rates as determined by
> clk_core_get_boundaries, taking all consumer requests into account.
>
> This information does not appear to be otherwise exposed to userspace.
>
> Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>

Thanks for your patch!

> --- a/drivers/clk/clk.c
> +++ b/drivers/clk/clk.c
> @@ -3031,10 +3031,34 @@ static int clk_duty_cycle_show(struct seq_file *s, void *data)
>
>         return 0;
>  }
>  DEFINE_SHOW_ATTRIBUTE(clk_duty_cycle);
>
> +static int clk_min_rate_show(struct seq_file *s, void *data)
> +{
> +       struct clk_core *core = s->private;
> +       unsigned long min_rate, max_rate;
> +
> +       clk_core_get_boundaries(core, &min_rate, &max_rate);

Probably you should clk_prepare_lock() first?

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds