[PATCH 2/4] ASoC: SOF: Intel: lnl: add helper to detect SoundWire wakes

[Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>]

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@xxxxxxxxxxxxxxx>
Reviewed-by: Bard Liao <yung-chuan.liao@xxxxxxxxxxxxxxx>
Reviewed-by: Rander Wang <rander.wang@xxxxxxxxx>
---
 sound/soc/sof/intel/lnl.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/sound/soc/sof/intel/lnl.c b/sound/soc/sof/intel/lnl.c
index 95da0c626832..c3ee507e2e21 100644
--- a/sound/soc/sof/intel/lnl.c
+++ b/sound/soc/sof/intel/lnl.c
@@ -205,6 +205,23 @@ 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),
@@ -221,6 +238,7 @@ 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,
-- 
2.40.1