ASoC: SOF: Intel: lnl: add helper to detect SoundWire wakes

The global STATESTS register will provide information on all
links. Rather than iterate on all possible links, the helpers only
filters the range of possible bits for a quick lookup. The
process_wakeen() helper will walk through all the links and deal with
wakes.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Link: https://msgid.link/r/20240404190357.138073-3-pierre-louis.bossart@linux.intel.comSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/sof/intel/lnl.c

@@ -189,6 +189,23 @@ static int lnl_dsp_disable_interrupts(struct snd_sof_dev *sdev)
 	return mtl_enable_interrupts(sdev, false);
 }
 
+static bool lnl_sdw_check_wakeen_irq(struct snd_sof_dev *sdev)
+{
+	struct hdac_bus *bus = sof_to_bus(sdev);
+	u16 wake_sts;
+
+	/*
+	 * we need to use the global HDaudio WAKEEN/STS to be able to
+	 * detect wakes in low-power modes. The link-specific information
+	 * is handled in the process_wakeen() helper, this helper only
+	 * detects a SoundWire wake without identifying the link.
+	 */
+	wake_sts = snd_hdac_chip_readw(bus, STATESTS);
+
+	/* filter out the range of SDIs that can be set for SoundWire */
+	return wake_sts & GENMASK(SDW_MAX_DEVICES, SDW_INTEL_DEV_NUM_IDA_MIN);
+}
+
 const struct sof_intel_dsp_desc lnl_chip_info = {
 	.cores_num = 5,
 	.init_core_mask = BIT(0),
@@ -205,6 +222,7 @@ const struct sof_intel_dsp_desc lnl_chip_info = {
 	.read_sdw_lcount =  hda_sdw_check_lcount_ext,
 	.enable_sdw_irq = lnl_enable_sdw_irq,
 	.check_sdw_irq = lnl_dsp_check_sdw_irq,
+	.check_sdw_wakeen_irq = lnl_sdw_check_wakeen_irq,
 	.check_ipc_irq = mtl_dsp_check_ipc_irq,
 	.cl_init = mtl_dsp_cl_init,
 	.power_down_dsp = mtl_power_down_dsp,