2017-03-21 13:21:33

by Peter De Schrijver

[permalink] [raw]
Subject: [PATCH] clk: add clk_possible_parents debugfs file

For validation purposes, it's often useful to be able to retrieve the list
of possible parents in userspace. Add a debugfs file for every clock which
has more than 1 possible parent.

Signed-off-by: Peter De Schrijver <[email protected]>
Reviewed-by: Jon Mayo <[email protected]>
---
drivers/clk/clk.c | 35 +++++++++++++++++++++++++++++++++++
1 file changed, 35 insertions(+)

diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index f5f2bcd..2fa2fb8 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -2128,6 +2128,34 @@ static int clk_dump_open(struct inode *inode, struct file *file)
.release = single_release,
};

+static int possible_parents_dump(struct seq_file *s, void *data)
+{
+ struct clk_core *core;
+ int i;
+
+ core = (struct clk_core *)s->private;
+
+ for (i = 0; i < core->num_parents - 1; i++)
+ seq_printf(s, "%s ", core->parent_names[i]);
+
+ seq_printf(s, "%s\n", core->parent_names[i]);
+
+ return 0;
+}
+
+static int possible_parents_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, possible_parents_dump, inode->i_private);
+}
+
+
+static const struct file_operations possible_parents_fops = {
+ .open = possible_parents_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
static int clk_debug_create_one(struct clk_core *core, struct dentry *pdentry)
{
struct dentry *d;
@@ -2179,6 +2207,13 @@ static int clk_debug_create_one(struct clk_core *core, struct dentry *pdentry)
if (!d)
goto err_out;

+ if (core->num_parents > 1) {
+ d = debugfs_create_file("clk_possible_parents", S_IRUGO,
+ core->dentry, core, &possible_parents_fops);
+ if (!d)
+ goto err_out;
+ }
+
if (core->ops->debug_init) {
ret = core->ops->debug_init(core->hw, core->dentry);
if (ret)
--
1.9.1


2017-04-07 19:45:15

by Stephen Boyd

[permalink] [raw]
Subject: Re: [PATCH] clk: add clk_possible_parents debugfs file

On 03/21, Peter De Schrijver wrote:
> diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
> index f5f2bcd..2fa2fb8 100644
> --- a/drivers/clk/clk.c
> +++ b/drivers/clk/clk.c
> @@ -2128,6 +2128,34 @@ static int clk_dump_open(struct inode *inode, struct file *file)
> .release = single_release,
> };
>
> +static int possible_parents_dump(struct seq_file *s, void *data)
> +{
> + struct clk_core *core;
> + int i;
> +
> + core = (struct clk_core *)s->private;

Useless cast from void.

> +
> + for (i = 0; i < core->num_parents - 1; i++)
> + seq_printf(s, "%s ", core->parent_names[i]);

I hope we don't have spaces in clk names! I don't think we do.

> +
> + seq_printf(s, "%s\n", core->parent_names[i]);
> +
> + return 0;
> +}
> +
> +static int possible_parents_open(struct inode *inode, struct file *file)
> +{
> + return single_open(file, possible_parents_dump, inode->i_private);
> +}
> +
> +

Double newline.

I fixed both when applying to clk-next.

--
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project

2017-04-11 13:47:55

by Peter De Schrijver

[permalink] [raw]
Subject: Re: [PATCH] clk: add clk_possible_parents debugfs file

On Fri, Apr 07, 2017 at 12:45:06PM -0700, Stephen Boyd wrote:
> On 03/21, Peter De Schrijver wrote:
> > diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
> > index f5f2bcd..2fa2fb8 100644
> > --- a/drivers/clk/clk.c
> > +++ b/drivers/clk/clk.c
> > @@ -2128,6 +2128,34 @@ static int clk_dump_open(struct inode *inode, struct file *file)
> > .release = single_release,
> > };
> >
> > +static int possible_parents_dump(struct seq_file *s, void *data)
> > +{
> > + struct clk_core *core;
> > + int i;
> > +
> > + core = (struct clk_core *)s->private;
>
> Useless cast from void.
>
> > +
> > + for (i = 0; i < core->num_parents - 1; i++)
> > + seq_printf(s, "%s ", core->parent_names[i]);
>
> I hope we don't have spaces in clk names! I don't think we do.
>

I don't think we do either, at least I've never seen a clk name with a space.

Peter.