Provide /sys/kernel/debug/clock to ease debugging.
Signed-off-by: Dmitry Baryshkov <dbaryshkov@gmail.com>
---
include/linux/clklib.h | 5 +++
kernel/clklib.c | 68 ++++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 73 insertions(+), 0 deletions(-)
diff --git a/include/linux/clklib.h b/include/linux/clklib.h
index 4bd9b4a..f916693 100644
--- a/include/linux/clklib.h
+++ b/include/linux/clklib.h
@@ -28,6 +28,11 @@ struct clk {
int (*setrate) (struct clk *, unsigned long);
long (*roundrate) (struct clk *, unsigned long);
+ /*
+ * format any additional info
+ */
+ int (*format) (struct clk *, struct seq_file *);
+
void *priv;
};
diff --git a/kernel/clklib.c b/kernel/clklib.c
index 203af3d..b782220 100644
--- a/kernel/clklib.c
+++ b/kernel/clklib.c
@@ -293,3 +293,71 @@ out:
return rc;
}
EXPORT_SYMBOL(clk_alloc_function);
+
+#ifdef CONFIG_DEBUG_FS
+
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
+static void dump_clocks(struct seq_file *s, struct clk *parent, int nest)
+{
+ struct clk *clk;
+ int i;
+
+ list_for_each_entry(clk, &clocks, node) {
+ if (clk->parent == parent) {
+ for (i = 0; i < nest; i++)
+ seq_putc(s, ' ');
+ seq_puts(s, clk->name);
+
+ i = nest + strlen(clk->name);
+ if (i >= 16)
+ i = 15;
+ for (; i < 16; i++)
+ seq_putc(s, ' ');
+ seq_printf(s, "%c use=%d rate=%lu KHz",
+ clk->set_parent ? '*' : ' ',
+ clk->users,
+ __clk_get_rate(clk));
+ if (clk->format)
+ clk->format(clk, s);
+ seq_putc(s, '\n');
+
+ dump_clocks(s, clk, nest + 1);
+ }
+ }
+}
+
+static int clocklib_show(struct seq_file *s, void *unused)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&clocks_lock, flags);
+
+ dump_clocks(s, NULL, 0);
+
+ spin_unlock_irqrestore(&clocks_lock, flags);
+
+ return 0;
+}
+
+static int clocklib_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, clocklib_show, NULL);
+}
+
+static struct file_operations clocklib_operations = {
+ .open = clocklib_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static int __init clocklib_debugfs_init(void)
+{
+ debugfs_create_file("clock", S_IFREG | S_IRUGO,
+ NULL, NULL, &clocklib_operations);
+ return 0;
+}
+subsys_initcall(clocklib_debugfs_init);
+
+#endif /* DEBUG_FS */
--
1.5.3.8
--
With best wishes
Dmitry
--
