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WM8904: Add logic to analyze BCLK setup

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This commit is contained in:
Gregory Nutt 2014-08-03 17:11:38 -06:00
parent b9384ced60
commit 72b739fbcb
6 changed files with 358 additions and 109 deletions
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6
drivers/audio/Kconfig
View File

@ -137,6 +137,12 @@ config WM8904_REGDUMP
---help---
Enable logic to dump the contents of all WM8904 registers.
config WM8904_CLKDEBUG
bool "WM8904 clock analysis"
default n
---help---
Enable logic to analyze WM8904 clock configuation.
endif # AUDIO_WM8904
config AUDIO_NULL

4
drivers/audio/Make.defs
View File

@ -47,6 +47,10 @@ ifeq ($(CONFIG_AUDIO_WM8904),y)
CSRCS += wm8904.c
ifeq ($(CONFIG_WM8904_REGDUMP),y)
CSRCS += wm8904_debug.c
else
ifeq ($(CONFIG_WM8904_CLKDEBUG),y)
CSRCS += wm8904_debug.c
endif
endif
endif

116
drivers/audio/wm8904.c
View File

@ -75,99 +75,15 @@
* Pre-processor Definitions
****************************************************************************/
/* Dummy register address */
#define WM8904_DUMMY 0xff
/* Default FLL configuration */
#define WM8904_DEFAULT_SAMPRATE 11025
#define WM8904_DEFAULT_NCHANNELS 1
#define WM8904_DEFAULT_BPSAMP 16
#define WM8904_STARTBITS 2
#define WM8904_NFLLRATIO_DIV1 0
#define WM8904_NFLLRATIO_DIV2 1
#define WM8904_NFLLRATIO_DIV4 2
#define WM8904_NFLLRATIO_DIV8 3
#define WM8904_NFLLRATIO_DIV16 4
#define WM8904_NFLLRATIO 5
#define WM8904_MINOUTDIV 4
#define WM8904_MAXOUTDIV 64
#define WM8904_BCLK_MAXDIV 20
#define WM8904_FVCO_MIN 90000000
#define WM8904_FVCO_MAX 100000000
/* Commonly defined and redefined macros */
#ifndef MIN
# define MIN(a,b) (((a) < (b)) ? (a) : (b))
#endif
#ifndef MAX
# define MAX(a,b) (((a) > (b)) ? (a) : (b))
#endif
/****************************************************************************
* Private Types
****************************************************************************/
struct wm8904_dev_s
{
/* We are an audio lower half driver (We are also the upper "half" of
* the WM8904 driver with respect to the board lower half driver).
*
* Terminology: Our "lower" half audio instances will be called dev for the
* publicly visible version and "priv" for the version that only this driver
* knows. From the point of view of this driver, it is the board lower
* "half" that is referred to as "lower".
*/
struct audio_lowerhalf_s dev; /* WM8904 audio lower half (this device) */
/* Our specific driver data goes here */
const FAR struct wm8904_lower_s *lower; /* Pointer to the board lower functions */
FAR struct i2c_dev_s *i2c; /* I2C driver to use */
FAR struct i2s_dev_s *i2s; /* I2S driver to use */
struct dq_queue_s pendq; /* Queue of pending buffers to be sent */
struct dq_queue_s doneq; /* Queue of sent buffers to be returned */
mqd_t mq; /* Message queue for receiving messages */
char mqname[16]; /* Our message queue name */
pthread_t threadid; /* ID of our thread */
uint32_t bitrate; /* Actual programmed bit rate */
sem_t pendsem; /* Protect pendq */
uint16_t samprate; /* Configured samprate (samples/sec) */
#ifndef CONFIG_AUDIO_EXCLUDE_VOLUME
#ifndef CONFIG_AUDIO_EXCLUDE_BALANCE
uint16_t balance; /* Current balance level (b16) */
#endif /* CONFIG_AUDIO_EXCLUDE_BALANCE */
uint8_t volume; /* Current volume level {0..63} */
#endif /* CONFIG_AUDIO_EXCLUDE_VOLUME */
uint8_t nchannels; /* Number of channels (1 or 2) */
uint8_t bpsamp; /* Bits per sample (8 or 16) */
volatile uint8_t inflight; /* Number of audio buffers in-flight */
bool running; /* True: Worker thread is running */
bool paused; /* True: Playing is paused */
bool mute; /* True: Output is muted */
#ifndef CONFIG_AUDIO_EXCLUDE_STOP
bool terminating; /* True: Stop requested */
#endif
bool reserved; /* True: Device is reserved */
volatile int result; /* The result of the last transfer */
};
static const uint8_t g_fllratio[WM8904_NFLLRATIO] = {1, 2, 4, 8, 16};
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
#ifndef CONFIG_WM8904_REGDUMP
#if !defined(CONFIG_WM8904_REGDUMP) && !defined(CONFIG_WM8904_CLKDEBUG)
static
#endif
uint16_t wm8904_readreg(FAR struct wm8904_dev_s *priv,
@ -289,13 +205,21 @@ static const struct audio_ops_s g_audioops =
wm8904_release /* release */
};
static const uint8_t g_sysclk_scaleb1[WM8904_BCLK_MAXDIV+1] =
#ifndef CONFIG_WM8904_CLKDEBUG
static
#endif
const uint8_t g_sysclk_scaleb1[WM8904_BCLK_MAXDIV+1] =
{
2, 3, 4, 6, 8, 10, 11, /* 1, 1.5, 2, 3, 4, 5, 5.5 */
12, 16, 20, 22, 24, 32, 40, /* 6, 8, 10, 11, 12, 16, 20 */
44, 48, 50, 60, 64, 88, 96 /* 22, 24, 25, 30, 32, 44, 48 */
};
#ifndef CONFIG_WM8904_CLKDEBUG
static
#endif
const uint8_t g_fllratio[WM8904_NFLLRATIO] = {1, 2, 4, 8, 16};
/****************************************************************************
* Private Functions
****************************************************************************/
@ -308,7 +232,7 @@ static const uint8_t g_sysclk_scaleb1[WM8904_BCLK_MAXDIV+1] =
*
****************************************************************************/
#ifndef CONFIG_WM8904_REGDUMP
#if !defined(CONFIG_WM8904_REGDUMP) && !defined(CONFIG_WM8904_CLKDEBUG)
static
#endif
uint16_t wm8904_readreg(FAR struct wm8904_dev_s *priv, uint8_t regaddr)
@ -900,7 +824,7 @@ static void wm8904_setbitrate(FAR struct wm8904_dev_s *priv)
*
* Already set above
*/
/* Allow time for FLL lock. Typical is 2 MSec. Lock status is available
* in the WM8904 interrupt status register.
*/
@ -911,19 +835,6 @@ static void wm8904_setbitrate(FAR struct wm8904_dev_s *priv)
regval = WM8904_FLL_FRACN_ENA | WM8904_FLL_ENA;
wm8904_writereg(priv, WM8904_FLL_CTRL1, regval);
/* Dump all FLL registers */
audvdbg("FLL control 1[%02x]: %04x\n",
WM8904_FLL_CTRL1, wm8904_readreg(priv, WM8904_FLL_CTRL1));
audvdbg("FLL control 2[%02x]: %04x\n",
WM8904_FLL_CTRL2, wm8904_readreg(priv, WM8904_FLL_CTRL2));
audvdbg("FLL control 3[%02x]: %04x\n",
WM8904_FLL_CTRL3, wm8904_readreg(priv, WM8904_FLL_CTRL3));
audvdbg("FLL control 4[%02x]: %04x\n",
WM8904_FLL_CTRL4, wm8904_readreg(priv, WM8904_FLL_CTRL4));
audvdbg("FLL control 5[%02x]: %04x\n",
WM8904_FLL_CTRL5, wm8904_readreg(priv, WM8904_FLL_CTRL5));
}
/****************************************************************************
@ -1260,6 +1171,8 @@ static int wm8904_configure(FAR struct audio_lowerhalf_s *dev,
wm8904_setbitrate(priv);
wm8904_setlrclock(priv);
wm8904_writereg(priv, WM8904_DUMMY, 0x55aa);
wm8904_clock_analysis(&priv->dev, "AUDIO_TYPE_OUTPUT");
ret = OK;
}
break;
@ -2375,6 +2288,7 @@ FAR struct audio_lowerhalf_s *
wm8904_audio_output(priv);
wm8904_dump_registers(&priv->dev, "After configuration");
wm8904_clock_analysis(&priv->dev, "After configuration");
/* Attach our ISR to this device */

93
drivers/audio/wm8904.h
View File

@ -47,6 +47,9 @@
#include <nuttx/config.h>
#include <nuttx/compiler.h>
#include <pthread.h>
#include <mqueue.h>
#include <nuttx/fs/ioctl.h>
#ifdef CONFIG_AUDIO
@ -157,6 +160,8 @@
#define WM8904_FLL_NCO_TEST0 0xf7 /* FLL NCO Test 0 */
#define WM8904_FLL_NCO_TEST1 0xf8 /* FLL NCO Test 1 */
#define WM8904_DUMMY 0xff /* Dummy register address */
/* Register Default Values **************************************************/
/* Registers have some undocumented bits set on power up. These probably
* should be retained on writes (?).
@ -853,7 +858,7 @@
# define WM8904_FLL_CLK_REF_DIV4 (2 << WM8904_FLL_CLK_REF_DIV_SHIFT) /* MCLK / 4 */
# define WM8904_FLL_CLK_REF_DIV8 (3 << WM8904_FLL_CLK_REF_DIV_SHIFT) /* MCLK / 8 */
#define WM8904_FLL_CLK_REF_SRC_SHIFT (0) /* Bits 0-2: FLL clock source */
#define WM8904_FLL_CLK_REF_SRC_MASK (3) << WM8904_FLL_CLK_REF_SRC_SHIFT)
#define WM8904_FLL_CLK_REF_SRC_MASK (3 << WM8904_FLL_CLK_REF_SRC_SHIFT)
# define WM8904_FLL_CLK_REF_SRC_MCLK (0 << WM8904_FLL_CLK_REF_SRC_SHIFT)
# define WM8904_FLL_CLK_REF_SRC_BCLK (1 << WM8904_FLL_CLK_REF_SRC_SHIFT)
# define WM8904_FLL_CLK_REF_SRC_LRCLK (2 << WM8904_FLL_CLK_REF_SRC_SHIFT)
@ -977,14 +982,98 @@
/* 0xf8 FLL NCO Test 1 (16-bit FLL forced oscillator value */
/* FLL Configuration *********************************************************/
/* Default FLL configuration */
#define WM8904_DEFAULT_SAMPRATE 11025
#define WM8904_DEFAULT_NCHANNELS 1
#define WM8904_DEFAULT_BPSAMP 16
#define WM8904_STARTBITS 2
#define WM8904_NFLLRATIO_DIV1 0
#define WM8904_NFLLRATIO_DIV2 1
#define WM8904_NFLLRATIO_DIV4 2
#define WM8904_NFLLRATIO_DIV8 3
#define WM8904_NFLLRATIO_DIV16 4
#define WM8904_NFLLRATIO 5
#define WM8904_MINOUTDIV 4
#define WM8904_MAXOUTDIV 64
#define WM8904_BCLK_MAXDIV 20
#define WM8904_FVCO_MIN 90000000
#define WM8904_FVCO_MAX 100000000
/* Commonly defined and redefined macros */
#ifndef MIN
# define MIN(a,b) (((a) < (b)) ? (a) : (b))
#endif
#ifndef MAX
# define MAX(a,b) (((a) > (b)) ? (a) : (b))
#endif
/****************************************************************************
* Public Types
****************************************************************************/
struct wm8904_dev_s
{
/* We are an audio lower half driver (We are also the upper "half" of
* the WM8904 driver with respect to the board lower half driver).
*
* Terminology: Our "lower" half audio instances will be called dev for the
* publicly visible version and "priv" for the version that only this driver
* knows. From the point of view of this driver, it is the board lower
* "half" that is referred to as "lower".
*/
struct audio_lowerhalf_s dev; /* WM8904 audio lower half (this device) */
/* Our specific driver data goes here */
const FAR struct wm8904_lower_s *lower; /* Pointer to the board lower functions */
FAR struct i2c_dev_s *i2c; /* I2C driver to use */
FAR struct i2s_dev_s *i2s; /* I2S driver to use */
struct dq_queue_s pendq; /* Queue of pending buffers to be sent */
struct dq_queue_s doneq; /* Queue of sent buffers to be returned */
mqd_t mq; /* Message queue for receiving messages */
char mqname[16]; /* Our message queue name */
pthread_t threadid; /* ID of our thread */
uint32_t bitrate; /* Actual programmed bit rate */
sem_t pendsem; /* Protect pendq */
uint16_t samprate; /* Configured samprate (samples/sec) */
#ifndef CONFIG_AUDIO_EXCLUDE_VOLUME
#ifndef CONFIG_AUDIO_EXCLUDE_BALANCE
uint16_t balance; /* Current balance level (b16) */
#endif /* CONFIG_AUDIO_EXCLUDE_BALANCE */
uint8_t volume; /* Current volume level {0..63} */
#endif /* CONFIG_AUDIO_EXCLUDE_VOLUME */
uint8_t nchannels; /* Number of channels (1 or 2) */
uint8_t bpsamp; /* Bits per sample (8 or 16) */
volatile uint8_t inflight; /* Number of audio buffers in-flight */
bool running; /* True: Worker thread is running */
bool paused; /* True: Playing is paused */
bool mute; /* True: Output is muted */
#ifndef CONFIG_AUDIO_EXCLUDE_STOP
bool terminating; /* True: Stop requested */
#endif
bool reserved; /* True: Device is reserved */
volatile int result; /* The result of the last transfer */
};
/****************************************************************************
* Public Data
****************************************************************************/
#ifdef CONFIG_WM8904_CLKDEBUG
extern const uint8_t g_sysclk_scaleb1[WM8904_BCLK_MAXDIV+1];
extern const uint8_t g_fllratio[WM8904_NFLLRATIO];
#endif
/****************************************************************************
* Public Function Prototypes
****************************************************************************/
@ -997,7 +1086,7 @@
*
****************************************************************************/
#ifdef CONFIG_WM8904_REGDUMP
#if defined(CONFIG_WM8904_REGDUMP) || defined(CONFIG_WM8904_CLKDEBUG)
struct wm8904_dev_s;
uint16_t wm8904_readreg(FAR struct wm8904_dev_s *priv, uint8_t regaddr);
#endif

223
drivers/audio/wm8904_debug.c
View File

@ -48,14 +48,15 @@
#include <nuttx/config.h>
#include <stdint.h>
#include <assert.h>
#include <fixedmath.h>
#include <syslog.h>
#include <nuttx/audio/audio.h>
#include <nuttx/audio/wm8904.h>
#include "wm8904.h"
#ifdef CONFIG_WM8904_REGDUMP
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
@ -64,11 +65,13 @@
* Private Types
****************************************************************************/
struct wm8904_debug_s
#ifdef CONFIG_WM8904_REGDUMP
struct wb8904_regdump_s
{
FAR const char *regname;
uint8_t regaddr;
};
#endif
/****************************************************************************
* Private Function Prototypes
@ -78,7 +81,8 @@ struct wm8904_debug_s
* Private Data
****************************************************************************/
static const struct wm8904_debug_s g_wm8904_debug[] =
#ifdef CONFIG_WM8904_REGDUMP
static const struct wb8904_regdump_s g_wm8904_debug[] =
{
{"ID", WM8904_ID },
{"BIAS_CTRL", WM8904_BIAS_CTRL },
@ -180,7 +184,8 @@ static const struct wm8904_debug_s g_wm8904_debug[] =
{"FLL_NCO_TEST1", WM8904_FLL_NCO_TEST1 }
};
#define WM8904_NREGISTERS (sizeof(g_wm8904_debug)/sizeof(struct wm8904_debug_s))
# define WM8904_NREGISTERS (sizeof(g_wm8904_debug)/sizeof(struct wb8904_regdump_s))
#endif /* CONFIG_WM8904_REGDUMP */
/****************************************************************************
* Private Functions
@ -204,6 +209,7 @@ static const struct wm8904_debug_s g_wm8904_debug[] =
*
****************************************************************************/
#ifdef CONFIG_WM8904_REGDUMP
void wm8904_dump_registers(FAR struct audio_lowerhalf_s *dev,
FAR const char *msg)
{
@ -218,5 +224,210 @@ void wm8904_dump_registers(FAR struct audio_lowerhalf_s *dev,
g_wm8904_debug[i].regaddr));
}
}
#endif /* CONFIG_WM8904_REGDUMP */
/****************************************************************************
* Name: wm8904_clock_analysis
*
* Description:
* Analyze the settings in the clock chain and dump to syslog.
*
* Input Parameters:
* dev - The device instance returned by wm8904_initialize
*
* Returned Value:
* None.
*
****************************************************************************/
#ifdef CONFIG_WM8904_CLKDEBUG
void wm8904_clock_analysis(FAR struct audio_lowerhalf_s *dev,
FAR const char *msg)
{
FAR struct wm8904_dev_s *priv = (FAR struct wm8904_dev_s *)dev;
uint32_t sysclk;
uint32_t bclk;
uint32_t lrclk;
uint16_t regval;
unsigned int tmp;
double ftmp;
syslog("WM8904 Clock Analysis: %s\n", msg);
DEBUGASSERT(priv && priv->lower);
syslog(" MCLK: %lu Hz\n", (unsigned long)priv->lower->mclk);
/* Is the SYSCLK source the FLL? Or MCK? */
regval = wm8904_readreg(priv, WM8904_CLKRATE2);
if ((regval & WM8904_SYSCLK_SRC) == WM8904_SYSCLK_SRCMCLK)
{
/* The SYSCLK divider bypasses the FLL and takes its input
* directly from MCLK.
*/
sysclk = priv->lower->mclk;
syslog(" SYSCLK Source: MCLK (%s)\n",
(regval & WM8904_MCLK_INV) != 0 ? "inverted" : "not inverted");
}
else
{
uint32_t fref;
uint32_t fvco;
uint32_t fout;
unsigned int outdiv;
unsigned int frndx;
unsigned int flln;
unsigned int fllk;
unsigned int fratio;
double nk;
/* Assume that the Fref input to the FLL is MCLK */
fref = priv->lower->mclk;
/* Now get the real FLL input source */
regval = wm8904_readreg(priv, WM8904_FLL_CTRL5);
switch (regval & WM8904_FLL_CLK_REF_SRC_MASK)
{
case WM8904_FLL_CLK_REF_SRC_MCLK:
syslog(" FLL Source: MCLK\n");
break;
case WM8904_FLL_CLK_REF_SRC_BCLK:
syslog(" ERROR: FLL source is BCLK: %04x\n", regval);
break;
case WM8904_FLL_CLK_REF_SRC_LRCLK:
syslog(" ERROR: FLL source is LRCLK: %04x\n", regval);
break;
default:
syslog(" ERROR: Unrecognized FLL source: %04x\n", regval);
}
syslog(" Fref: %lu Hz (before divider)\n", fref);
switch (regval & WM8904_FLL_CLK_REF_DIV_MASK)
{
case WM8904_FLL_CLK_REF_DIV1:
syslog(" FLL_CLK_REF_DIV: 1\n");
break;
case WM8904_FLL_CLK_REF_DIV2:
syslog(" FLL_CLK_REF_DIV: 2\n");
fref >>= 1;
break;
case WM8904_FLL_CLK_REF_DIV4:
syslog(" FLL_CLK_REF_DIV: 4\n");
fref >>= 2;
break;
case WM8904_FLL_CLK_REF_DIV8:
syslog(" FLL_CLK_REF_DIV: 8\n");
fref >>= 3;
break;
}
syslog(" Fref: %lu Hz (after divider)\n", fref);
regval = wm8904_readreg(priv, WM8904_FLL_CTRL2);
frndx = (regval & WM8904_FLL_FRATIO_MASK) >> WM8904_FLL_FRATIO_SHIFT;
tmp = (regval & WM8904_FLL_CTRL_RATE_MASK) >> WM8904_FLL_CTRL_RATE_SHIFT;
outdiv = ((regval & WM8904_FLL_OUTDIV_MASK) >> WM8904_FLL_OUTDIV_SHIFT) + 1;
syslog(" FLL_CTRL_RATE: Fvco / %u\n", tmp + 1);
regval = wm8904_readreg(priv, WM8904_FLL_CTRL4);
flln = (regval & WM8904_FLL_N_MASK) >> WM8904_FLL_N_SHIFT;
tmp = (regval & WM8904_FLL_GAIN_MASK) >> WM8904_FLL_GAIN_SHIFT;
syslog(" FLL_GAIN: %u\n", (1 << tmp));
fllk = wm8904_readreg(priv, WM8904_FLL_CTRL3);
nk = (double)flln + ((double)fllk / 65536.0);
fratio = g_fllratio[frndx];
syslog(" FLL_FRATIO: %u\n", fratio);
syslog(" FLL_OUTDIV: %u\n", outdiv);
syslog(" FLL_N.K: %u.%05u\n", flln, fllk);
ftmp = nk * (double)fref * (double)fratio;
fvco = (uint32_t)ftmp;
syslog(" Fvco: %lu Hz\n", (unsigned long)fvco);
fout = fvco / outdiv;
syslog(" Fout: %lu Hz\n", (unsigned long)fout);
regval = wm8904_readreg(priv, WM8904_FLL_CTRL1);
syslog(" FLL_FRACN_ENA: %s\n",
(regval & WM8904_FLL_FRACN_ENA) != 0 ? "Enabled" : "Disabled");
syslog(" FLL_OSC_ENA: %s\n",
(regval & WM8904_FLL_OSC_ENA) != 0 ? "Enabled" : "Disabled");
syslog(" FLL_ENA: %s\n",
(regval & WM8904_FLL_ENA) != 0 ? "Enabled" : "Disabled");
if ((regval & WM8904_FLL_ENA) == 0)
{
syslog(" No SYSCLK\n");
return;
}
sysclk = fout;
}
syslog(" SYSCLK: %lu Hz (before divider)\n", (unsigned long)sysclk);
regval = wm8904_readreg(priv, WM8904_CLKRATE0);
if ((regval & WM8904_MCLK_DIV) == WM8904_MCLK_DIV1)
{
syslog(" MCLK_DIV: 1\n");
}
else
{
syslog(" MCLK_DIV: 2\n");
sysclk >>=1;
}
syslog(" SYSCLK: %lu (after divider)\n", (unsigned long)sysclk);
regval = wm8904_readreg(priv, WM8904_CLKRATE2);
syslog(" CLK_SYS_ENA: %s\n",
(regval & WM8904_CLK_SYS_ENA) != 0 ? "Enabled" : "Disabled");
if ((regval & WM8904_CLK_SYS_ENA) == 0)
{
syslog(" No SYSCLK\n");
return;
}
regval = wm8904_readreg(priv, WM8904_AIF2);
tmp = (regval & WM8904_BCLK_DIV_MASK) >> WM8904_BCLK_DIV_SHIFT;
tmp = g_sysclk_scaleb1[tmp];
ftmp = (double)tmp / 2.0;
syslog(" BCLK_DIV: SYSCLK / %u.%01u\n",
(unsigned int)(tmp >> 1), (unsigned int)(5 * (tmp & 1)));
bclk = (uint32_t)(sysclk / ftmp);
syslog(" BCLK: %lu Hz\n", (unsigned long)bclk);
regval = wm8904_readreg(priv, WM8904_AIF1);
syslog(" BCLK_DIR: %s\n",
(regval & WM8904_BCLK_DIR) != 0 ? "Output" : "Input");
regval = wm8904_readreg(priv, WM8904_AIF3);
tmp = (regval & WM8904_LRCLK_RATE_MASK) >> WM8904_LRCLK_RATE_SHIFT;
lrclk = bclk / tmp;
syslog(" LRCLK_RATE: BCLK / %lu\n", (unsigned long)tmp);
syslog(" LRCLK: %lu\n", (unsigned long)lrclk);
syslog(" LRCLK_DIR: %s\n",
(regval & WM8904_LRCLK_DIR) != 0 ? "Output" : "Input");
}
#endif /* CONFIG_WM8904_CLKDEBUG */

25
include/nuttx/audio/wm8904.h
View File

@ -245,6 +245,31 @@ void wm8904_dump_registers(FAR struct audio_lowerhalf_s *dev,
# define wm8904_dump_registers(d,m)
#endif
/****************************************************************************
* Name: wm8904_clock_analysis
*
* Description:
* Analyze the settings in the clock chain and dump to syslog.
*
* Input Parameters:
* dev - The device instance returned by wm8904_initialize
*
* Returned Value:
* None.
*
****************************************************************************/
#ifdef CONFIG_WM8904_CLKDEBUG
void wm8904_clock_analysis(FAR struct audio_lowerhalf_s *dev,
FAR const char *msg);
#else
/* This eliminates the need for any conditional compilation in the
* including file.
*/
# define wm8904_clock_analysis(d,m)
#endif
#undef EXTERN
#ifdef __cplusplus
}