sound: Add uclass operations for beeping

Some audio codecs such as Intel HDA do not need to use digital data to
play sounds, but instead have a way to emit beeps. Add this interface as
an option. If the beep interface is not supported, then the sound uclass
falls back to the I2S interface.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

arch/sandbox/include/asm/test.h

@@ -161,6 +161,22 @@ int sandbox_get_setup_called(struct udevice *dev);
  */
 int sandbox_get_sound_sum(struct udevice *dev);
 
+/**
+ * sandbox_set_allow_beep() - Set whether the 'beep' interface is supported
+ *
+ * @dev: Device to update
+ * @allow: true to allow the start_beep() method, false to disallow it
+ */
+void sandbox_set_allow_beep(struct udevice *dev, bool allow);
+
+/**
+ * sandbox_get_beep_frequency() - Get the frequency of the current beep
+ *
+ * @dev: Device to check
+ * @return frequency of beep, if there is an active beep, else 0
+ */
+int sandbox_get_beep_frequency(struct udevice *dev);
+
 /**
  * sandbox_get_pch_spi_protect() - Get the PCI SPI protection status
  *

drivers/sound/sandbox.c

@@ -24,7 +24,9 @@ struct sandbox_i2s_priv {
 
 struct sandbox_sound_priv {
 	int setup_called;
-	int sum;	/* Use to sum the provided audio data */
+	int sum;		/* Use to sum the provided audio data */
+	bool allow_beep;	/* true to allow the start_beep() interface */
+	int frequency_hz;	/* Beep frequency if active, else 0 */
 };
 
 void sandbox_get_codec_params(struct udevice *dev, int *interfacep, int *ratep,
@@ -61,6 +63,20 @@ int sandbox_get_sound_sum(struct udevice *dev)
 	return priv->sum;
 }
 
+void sandbox_set_allow_beep(struct udevice *dev, bool allow)
+{
+	struct sandbox_sound_priv *priv = dev_get_priv(dev);
+
+	priv->allow_beep = allow;
+}
+
+int sandbox_get_beep_frequency(struct udevice *dev)
+{
+	struct sandbox_sound_priv *priv = dev_get_priv(dev);
+
+	return priv->frequency_hz;
+}
+
 static int sandbox_codec_set_params(struct udevice *dev, int interface,
 				    int rate, int mclk_freq,
 				    int bits_per_sample, uint channels)
@@ -128,6 +144,28 @@ static int sandbox_sound_play(struct udevice *dev, void *data, uint data_size)
 	return i2s_tx_data(uc_priv->i2s, data, data_size);
 }
 
+int sandbox_sound_start_beep(struct udevice *dev, int frequency_hz)
+{
+	struct sandbox_sound_priv *priv = dev_get_priv(dev);
+
+	if (!priv->allow_beep)
+		return -ENOSYS;
+	priv->frequency_hz = frequency_hz;
+
+	return 0;
+}
+
+int sandbox_sound_stop_beep(struct udevice *dev)
+{
+	struct sandbox_sound_priv *priv = dev_get_priv(dev);
+
+	if (!priv->allow_beep)
+		return -ENOSYS;
+	priv->frequency_hz = 0;
+
+	return 0;
+}
+
 static int sandbox_sound_probe(struct udevice *dev)
 {
 	return sound_find_codec_i2s(dev);
@@ -169,8 +207,10 @@ U_BOOT_DRIVER(sandbox_i2s) = {
 };
 
 static const struct sound_ops sandbox_sound_ops = {
-	.setup	= sandbox_sound_setup,
-	.play	= sandbox_sound_play,
+	.setup		= sandbox_sound_setup,
+	.play		= sandbox_sound_play,
+	.start_beep	= sandbox_sound_start_beep,
+	.stop_beep	= sandbox_sound_stop_beep,
 };
 
 static const struct udevice_id sandbox_sound_ids[] = {

drivers/sound/sound-uclass.c

@@ -31,10 +31,30 @@ int sound_play(struct udevice *dev, void *data, uint data_size)
 	return ops->play(dev, data, data_size);
 }
 
+int sound_start_beep(struct udevice *dev, int frequency_hz)
+{
+	struct sound_ops *ops = sound_get_ops(dev);
+
+	if (!ops->start_beep)
+		return -ENOSYS;
+
+	return ops->start_beep(dev, frequency_hz);
+}
+
+int sound_stop_beep(struct udevice *dev)
+{
+	struct sound_ops *ops = sound_get_ops(dev);
+
+	if (!ops->stop_beep)
+		return -ENOSYS;
+
+	return ops->stop_beep(dev);
+}
+
 int sound_beep(struct udevice *dev, int msecs, int frequency_hz)
 {
 	struct sound_uc_priv *uc_priv = dev_get_uclass_priv(dev);
-	struct i2s_uc_priv *i2s_uc_priv = dev_get_uclass_priv(uc_priv->i2s);
+	struct i2s_uc_priv *i2s_uc_priv;
 	unsigned short *data;
 	uint data_size;
 	int ret;
@@ -43,7 +63,19 @@ int sound_beep(struct udevice *dev, int msecs, int frequency_hz)
 	if (ret && ret != -EALREADY)
 		return ret;
 
+	/* Try using the beep interface if available */
+	ret = sound_start_beep(dev, frequency_hz);
+	if (ret != -ENOSYS) {
+		if (ret)
+			return ret;
+		mdelay(msecs);
+		ret = sound_stop_beep(dev);
+
+		return ret;
+	}
+
 	/* Buffer length computation */
+	i2s_uc_priv = dev_get_uclass_priv(uc_priv->i2s);
 	data_size = i2s_uc_priv->samplingrate * i2s_uc_priv->channels;
 	data_size *= (i2s_uc_priv->bitspersample / SOUND_BITS_IN_BYTE);
 	data = malloc(data_size);

include/sound.h

@@ -67,6 +67,28 @@ struct sound_ops {
 	 * @return 0 if OK, -ve on error
 	 */
 	int (*play)(struct udevice *dev, void *data, uint data_size);
+
+	/**
+	 * start_beep() - Start beeping (optional)
+	 *
+	 * This tells the sound hardware to start a beep. It will continue until
+	 * stopped by sound_stop_beep().
+	 *
+	 * @dev: Sound device
+	 * @frequency_hz: Beep frequency in hertz
+	 * @return if OK, -ENOSYS if not supported, -ve on error
+	 */
+	int (*start_beep)(struct udevice *dev, int frequency_hz);
+
+	/**
+	 * stop_beep() - Stop beeping (optional)
+	 *
+	 * This tells the sound hardware to stop a previously started beep.
+	 *
+	 * @dev: Sound device
+	 * @return if OK, -ve on error
+	 */
+	int (*stop_beep)(struct udevice *dev);
 };
 
 #define sound_get_ops(dev)	((struct sound_ops *)(dev)->driver->ops)
@@ -86,6 +108,28 @@ int sound_setup(struct udevice *dev);
  */
 int sound_beep(struct udevice *dev, int msecs, int frequency_hz);
 
+/**
+ * sound_start_beep() - Start beeping
+ *
+ * This tells the sound hardware to start a beep. It will continue until stopped
+ * by sound_stop_beep().
+ *
+ * @dev: Sound device
+ * @frequency_hz: Beep frequency in hertz
+ * @return if OK, -ve on error
+ */
+int sound_start_beep(struct udevice *dev, int frequency_hz);
+
+/**
+ * sound_stop_beep() - Stop beeping
+ *
+ * This tells the sound hardware to stop a previously started beep.
+ *
+ * @dev: Sound device
+ * @return if OK, -ve on error
+ */
+int sound_stop_beep(struct udevice *dev);
+
 /**
  * sound_find_codec_i2s() - Called by sound drivers to locate codec and i2s
  *

test/dm/sound.c

@@ -32,3 +32,24 @@ static int dm_test_sound(struct unit_test_state *uts)
 	return 0;
 }
 DM_TEST(dm_test_sound, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);
+
+/* Test of the 'start beep' operations */
+static int dm_test_sound_beep(struct unit_test_state *uts)
+{
+	struct udevice *dev;
+
+	/* check probe success */
+	ut_assertok(uclass_first_device_err(UCLASS_SOUND, &dev));
+	ut_asserteq(-ENOSYS, sound_start_beep(dev, 100));
+	ut_asserteq(0, sandbox_get_beep_frequency(dev));
+
+	sandbox_set_allow_beep(dev, true);
+	ut_asserteq(0, sound_start_beep(dev, 100));
+	ut_asserteq(100, sandbox_get_beep_frequency(dev));
+
+	ut_asserteq(0, sound_stop_beep(dev));
+	ut_asserteq(0, sandbox_get_beep_frequency(dev));
+
+	return 0;
+}
+DM_TEST(dm_test_sound_beep, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);