ASoC: Intel: catpt: New volume and mute control operations

The catpt-driver's volume and mute control operations always return '0'
regardless if a change occurred or not. To conform to ALSA's interface,
value '1' shall be returned when a change occurred.

The second major point is power consumption. Existing control operations
always wake the DSP even if no streams are running. In such case waking
the DSP just for the sake of updating the volume (or mute) settings on
the firmware side is a waste of power. The provided implementation
caches the values and updates the settings only when streams are being
opened for streaming or are already running.

As changing existing code is non-trivial, provide new operations
instead. The put() operation, which interests us the most, takes the
following shape:

	// two values provided to put():
	// pin_id - which stream given control relates to
	// value_to_apply - the value from user

	if (control->existing_val == value_to_apply)
		return 0;

	runtime_stream = get_running_stream(pin_id);
	if (runtime_stream != NULL) {
		ret = send_ipc();
		if (ret)
			return ret;
	}

	control->existing_val = value_to_apply;
	return 1;

Adheres to ALSA's expectation and avoids sending IPCs if there is no
change to be made.

Two helpers which are part of the patch, catpt_stream_hw_id() and
catpt_stream_volume_regs(), help differentiate between individual
streams and the general MIXER stream. Translates to one pair of
get()/put() instead of two pairs as done currently.

PIN_ID_INVALID is returned if given stream is not currently running -
the constant is part of the firmware's API but remained unused by the
driver.

Signed-off-by: Cezary Rojewski <cezary.rojewski@intel.com>
Link: https://patch.msgid.link/20260309091605.896307-3-cezary.rojewski@intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>

0 files changed, 0 insertions, 0 deletions