ALSA: Add debug module option

Add debug module option to snd core.
This controls the debug print level.  When CONFIG_SND_DEBUG_VERBOSE
is set, you can suppress the debug messages by giving or changing this
parameter to a lower value.  debug=0 means no debug messsages.
As default, it's set to the verbose level 2.

Since this option can be changed dynamically via sysfs file, you can
suppress the verbose debug messages on the fly, which wasn't possible
before.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 14 insertions, 24 deletions

diff --git a/include/sound/core.h b/include/sound/core.h
index 309cb9659a05..a89728db5584 100644
--- a/include/sound/core.h
+++ b/include/sound/core.h
@@ -340,18 +340,17 @@ unsigned int snd_dma_pointer(unsigned long dma, unsigned int size);
 struct resource;
 void release_and_free_resource(struct resource *res);
 
-#ifdef CONFIG_SND_VERBOSE_PRINTK
-void snd_verbose_printk(const char *file, int line, const char *format, ...)
-     __attribute__ ((format (printf, 3, 4)));
-#endif
-#if defined(CONFIG_SND_DEBUG) && defined(CONFIG_SND_VERBOSE_PRINTK)
-void snd_verbose_printd(const char *file, int line, const char *format, ...)
-     __attribute__ ((format (printf, 3, 4)));
-#endif
-
 /* --- */
 
-#ifdef CONFIG_SND_VERBOSE_PRINTK
+#if defined(CONFIG_SND_DEBUG) || defined(CONFIG_SND_VERBOSE_PRINTK)
+void __snd_printk(unsigned int level, const char *file, int line,
+                  const char *format, ...)
+     __attribute__ ((format (printf, 4, 5)));
+#else
+#define __snd_printk(level, file, line, format, args...) \
+        prinkt(format, ##args)
+#endif
+
 /**
  * snd_printk - printk wrapper
  * @fmt: format string
@@ -360,15 +359,9 @@ void snd_verbose_printd(const char *file, int line, const char *format, ...)
  * when configured with CONFIG_SND_VERBOSE_PRINTK.
  */
 #define snd_printk(fmt, args...) \
-        snd_verbose_printk(__FILE__, __LINE__, fmt ,##args)
-#else
-#define snd_printk(fmt, args...) \
-        printk(fmt ,##args)
-#endif
+        __snd_printk(0, __FILE__, __LINE__, fmt, ##args)
 
 #ifdef CONFIG_SND_DEBUG
-
-#ifdef CONFIG_SND_VERBOSE_PRINTK
 /**
  * snd_printd - debug printk
  * @fmt: format string
@@ -377,11 +370,7 @@ void snd_verbose_printd(const char *file, int line, const char *format, ...)
  * Ignored when CONFIG_SND_DEBUG is not set.
  */
 #define snd_printd(fmt, args...) \
-        snd_verbose_printd(__FILE__, __LINE__, fmt ,##args)
-#else
-#define snd_printd(fmt, args...) \
-        printk(fmt ,##args)
-#endif
+        __snd_printk(1, __FILE__, __LINE__, fmt, ##args)
 
 /**
  * snd_BUG - give a BUG warning message and stack trace
@@ -428,9 +417,10 @@ static inline int __snd_bug_on(int cond)
  * Works like snd_printk() for debugging purposes.
  * Ignored when CONFIG_SND_DEBUG_VERBOSE is not set.
  */
-#define snd_printdd(format, args...) snd_printk(format, ##args)
+#define snd_printdd(format, args...) \
+        __snd_printk(2, __FILE__, __LINE__, format, ##args)
 #else
-#define snd_printdd(format, args...) /* nothing */
+#define snd_printdd(format, args...)    do { } while (0)
 #endif