ASoC: SOF: Intel: hda: make DSPless mode work with DSP disabled in BIOS

When the DSP is disabled in the BIOS, the DSP_BAR and PP_BAR cannot be
accessed.

One possible objection noted in initial reviews is that this patch
adds a number of branches. However the number of branches is actually
limited in probe/suspend/resume routines mostly, so there isn't really
a degradation in terms of readability and maintainability. Adding yet
another level of abstraction/ops/callbacks would increase complexity
and not really help in terms of code reuse or readability and
maintainability. A split between controller and DSP driver would be
even more invasive.

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Reviewed-by: Péter Ujfalusi <peter.ujfalusi@linux.intel.com>
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
Link: https://lore.kernel.org/r/20230404092115.27949-7-peter.ujfalusi@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>

1 files changed, 23 insertions, 7 deletions

diff --git a/sound/soc/sof/intel/hda-dsp.c b/sound/soc/sof/intel/hda-dsp.c
index c9231aeacc53..23c05e6f424a 100644
--- a/sound/soc/sof/intel/hda-dsp.c
+++ b/sound/soc/sof/intel/hda-dsp.c
@@ -321,6 +321,9 @@ void hda_dsp_ipc_int_enable(struct snd_sof_dev *sdev)
 	struct sof_intel_hda_dev *hda = sdev->pdata->hw_pdata;
 	const struct sof_intel_dsp_desc *chip = hda->desc;
 
+	if (sdev->dspless_mode_selected)
+		return;
+
 	/* enable IPC DONE and BUSY interrupts */
 	snd_sof_dsp_update_bits(sdev, HDA_DSP_BAR, chip->ipc_ctl,
 			HDA_DSP_REG_HIPCCTL_DONE | HDA_DSP_REG_HIPCCTL_BUSY,
@@ -336,6 +339,9 @@ void hda_dsp_ipc_int_disable(struct snd_sof_dev *sdev)
 	struct sof_intel_hda_dev *hda = sdev->pdata->hw_pdata;
 	const struct sof_intel_dsp_desc *chip = hda->desc;
 
+	if (sdev->dspless_mode_selected)
+		return;
+
 	/* disable IPC interrupt */
 	snd_sof_dsp_update_bits(sdev, HDA_DSP_BAR, HDA_DSP_REG_ADSPIC,
 				HDA_DSP_ADSPIC_IPC, 0);
@@ -681,6 +687,9 @@ static int hda_suspend(struct snd_sof_dev *sdev, bool runtime_suspend)
 	/* power down all hda links */
 	hda_bus_ml_suspend(bus);
 
+	if (sdev->dspless_mode_selected)
+		goto skip_dsp;
+
 	ret = chip->power_down_dsp(sdev);
 	if (ret < 0) {
 		dev_err(sdev->dev, "failed to power down DSP during suspend\n");
@@ -694,6 +703,7 @@ static int hda_suspend(struct snd_sof_dev *sdev, bool runtime_suspend)
 	/* disable ppcap interrupt */
 	hda_dsp_ctrl_ppcap_enable(sdev, false);
 	hda_dsp_ctrl_ppcap_int_enable(sdev, false);
+skip_dsp:
 
 	/* disable hda bus irq and streams */
 	hda_dsp_ctrl_stop_chip(sdev);
@@ -744,9 +754,11 @@ static int hda_resume(struct snd_sof_dev *sdev, bool runtime_resume)
 			hda_codec_jack_check(sdev);
 	}
 
-	/* enable ppcap interrupt */
-	hda_dsp_ctrl_ppcap_enable(sdev, true);
-	hda_dsp_ctrl_ppcap_int_enable(sdev, true);
+	if (!sdev->dspless_mode_selected) {
+		/* enable ppcap interrupt */
+		hda_dsp_ctrl_ppcap_enable(sdev, true);
+		hda_dsp_ctrl_ppcap_int_enable(sdev, true);
+	}
 
 cleanup:
 	/* display codec can powered off after controller init */
@@ -843,8 +855,10 @@ int hda_dsp_runtime_suspend(struct snd_sof_dev *sdev)
 	};
 	int ret;
 
-	/* cancel any attempt for DSP D0I3 */
-	cancel_delayed_work_sync(&hda->d0i3_work);
+	if (!sdev->dspless_mode_selected) {
+		/* cancel any attempt for DSP D0I3 */
+		cancel_delayed_work_sync(&hda->d0i3_work);
+	}
 
 	/* stop hda controller and power dsp off */
 	ret = hda_suspend(sdev, true);
@@ -866,8 +880,10 @@ int hda_dsp_suspend(struct snd_sof_dev *sdev, u32 target_state)
 	};
 	int ret;
 
-	/* cancel any attempt for DSP D0I3 */
-	cancel_delayed_work_sync(&hda->d0i3_work);
+	if (!sdev->dspless_mode_selected) {
+		/* cancel any attempt for DSP D0I3 */
+		cancel_delayed_work_sync(&hda->d0i3_work);
+	}
 
 	if (target_state == SOF_DSP_PM_D0) {
 		/* Set DSP power state */