[PATCH V2] ARM: SAMSUNG: Add support for clock debugging through debug-fs interface

[Amit Daniel Kachhap]

Hi Mr Kim,

Thanks for your comments. Please see the inline comments below.

On 1 December 2010 13:08, Kukjin Kim <kgene.kim at samsung.com> wrote:
>
> Amit Daniel Kachhap wrote:
> >
> > This patch adds support for clock information exposed to debug-fs
> interface.
> >
> > Signed-off-by: Amit Daniel Kachhap <amit.daniel at samsung.com>
> > ---
> > Code modified for V2 version are,
> > a)Inserted the debug-fs code inside macro CONFIG_PM_DEBUG as suggested by
> > yong.shen at linaro.org.
>
> Could you please let me know why?
Actually this patch is mostly taken from omap architecture, so using
this macro in addition
to CONFIG_DEBUG_FS macro. Also it is better to enable all PM debugging
features with
one configuration parameter.

>
> > b)Removed macro CONFIG_PLAT_SAMSUNG and implemented other coding standards
> > as suggested by kgene.kim at samsung.com
> >
> >  arch/arm/plat-samsung/clock.c              |   91
> > ++++++++++++++++++++++++++++
> >  arch/arm/plat-samsung/include/plat/clock.h |    3 +
> >  2 files changed, 94 insertions(+), 0 deletions(-)
> >
> > diff --git a/arch/arm/plat-samsung/clock.c b/arch/arm/plat-samsung/clock.c
> > index e8d20b0..029a49d 100644
> > --- a/arch/arm/plat-samsung/clock.c
> > +++ b/arch/arm/plat-samsung/clock.c
> > @@ -39,6 +39,9 @@
> >  #include <linux/clk.h>
> >  #include <linux/spinlock.h>
> >  #include <linux/io.h>
> > +#if defined(CONFIG_DEBUG_FS)
> > +#include <linux/debugfs.h>
> > +#endif
> >
> >  #include <mach/hardware.h>
> >  #include <asm/irq.h>
> > @@ -447,3 +450,91 @@ int __init s3c24xx_register_baseclocks(unsigned long
> > xtal)
> >       return 0;
> >  }
> >
> > +#if defined(CONFIG_PM_DEBUG) && defined(CONFIG_DEBUG_FS)
>
> Hmm...please let me know the reason...
same reason as above.
>
> > +/* debugfs support to trace clock tree hierarchy and attributes */
> > +
> > +static struct dentry *clk_debugfs_root;
> > +
> > +static int clk_debugfs_register_one(struct clk *c)
> > +{
> > +     int err;
> > +     struct dentry *d, *child, *child_tmp;
> > +     struct clk *pa = c->parent;
> > +     char s[255];
> > +     char *p = s;
> > +
> > +     p += sprintf(p, "%s", c->name);
> > +     /*Append id field with name also*/
>
> No need above comment. If required, please add other comments also.
ok, will remove this comment in next patch.
>
> > +     if (c->id >= 0)
> > +             sprintf(p, ":%d", c->id);
> > +
> > +     d = debugfs_create_dir(s, pa ? pa->dent : clk_debugfs_root);
> > +     if (!d)
> > +             return -ENOMEM;
> > +
> > +     c->dent = d;
> > +
> > +     d = debugfs_create_u8("usecount", S_IRUGO, c->dent, (u8
> *)&c->usage);
> > +     if (!d) {
> > +             err = -ENOMEM;
> > +             goto err_out;
> > +     }
>
> 1 empty line would be helpful to read.
ok, will update this in next patch.
>
> > +     d = debugfs_create_u32("rate", S_IRUGO, c->dent, (u32 *)&c->rate);
> > +     if (!d) {
> > +             err = -ENOMEM;
> > +             goto err_out;
> > +     }
> > +     return 0;
> > +
> > +err_out:
> > +     d = c->dent;
> > +     list_for_each_entry_safe(child, child_tmp, &d->d_subdirs,
> d_u.d_child)
> > +             debugfs_remove(child);
> > +     debugfs_remove(c->dent);
> > +     return err;
> > +}
> > +
> > +static int clk_debugfs_register(struct clk *c)
> > +{
> > +     int err;
> > +     struct clk *pa = c->parent;
> > +
> > +     if (pa && !pa->dent) {
> > +             err = clk_debugfs_register(pa);
> > +             if (err)
> > +                     return err;
> > +     }
> > +
> > +     if (!c->dent) {
> > +             err = clk_debugfs_register_one(c);
> > +             if (err)
> > +                     return err;
> > +     }
> > +     return 0;
> > +}
> > +
> > +static int __init clk_debugfs_init(void)
> > +{
> > +     struct clk *c;
> > +     struct dentry *d;
> > +     int err;
> > +
> > +     d = debugfs_create_dir("clock", NULL);
> > +     if (!d)
> > +             return -ENOMEM;
> > +     clk_debugfs_root = d;
> > +
> > +     list_for_each_entry(c, &clocks, list) {
> > +             err = clk_debugfs_register(c);
> > +             if (err)
> > +                     goto err_out;
> > +     }
> > +     return 0;
> > +err_out:
> > +     debugfs_remove_recursive(clk_debugfs_root);
> > +     return err;
> > +}
> > +late_initcall(clk_debugfs_init);
> > +
> > +#endif /* defined(CONFIG_PM_DEBUG) && defined(CONFIG_DEBUG_FS) */
> > +
>
> No need last one empty line.
ok, will update this comment in next patch.
>
> > diff --git a/arch/arm/plat-samsung/include/plat/clock.h b/arch/arm/plat-
> > samsung/include/plat/clock.h
> > index 0fbcd0e..9a82b88 100644
> > --- a/arch/arm/plat-samsung/include/plat/clock.h
> > +++ b/arch/arm/plat-samsung/include/plat/clock.h
> > @@ -47,6 +47,9 @@ struct clk {
> >
> >       struct clk_ops          *ops;
> >       int                 (*enable)(struct clk *, int enable);
> > +#if defined(CONFIG_PM_DEBUG) && defined(CONFIG_DEBUG_FS)
> > +     struct dentry           *dent;  /* For visible tree hierarchy */
> > +#endif
> >  };
> >
> >  /* other clocks which may be registered by board support */
> > --
>
>
> Thanks.
>
> Best regards,
> Kgene.
> --
> Kukjin Kim <kgene.kim at samsung.com>, Senior Engineer,
> SW Solution Development Team, Samsung Electronics Co., Ltd.
>