ASoC: intel: Fix sst-dsp dependency on dw stuff

The recent commit [a92ea59b74e2: ASoC: Intel: sst: only select
sst-firmware when DW DMAC is built-in] introduced more strict kconfig
dependency (depends on DW_DMAC_CORE=y) for avoiding the build failures
due to dependency messes in intel-sst.  This makes, however, it
impossible to use this driver with the modularized systems,
i.e. typically on Linux distros.

The problem addressed in the commit above is that sst_dsp_new() and
sst_dsp_free() includes the firmware init / finish that call dw_*()
functions.  Thus building it as built-in with DW_DMAC_CORE module
results in the missing symbols.

However, these sst_dsp functions are basically called only from the
drivers that depend on DW_DMAC_CORE already.  That is, once when these
functions are split out, the rest can be independent from dw stuff.

This patch attempts to solve the issue by the following:
- Split sst-dsp stuff into two modules: snd-soc-sst-dsp and
  snd-soc-sst-firmware.
- Move sst_dsp_new() and sst_dsp_free() to the latter module so that
  the former module can be independent from DW_DMAC_CORE.
- Add a new kconfig SND_SOC_INTEL_SST_FIRMWARE to select the latter
  module by machine drivers.

One only remaining pitfall is that each machine driver has to select
SND_SOC_INTEL_SST_FIRMWARE carefully depending on DW_DMAC_CORE.
This can't be done cleanly due to the restriction of the current
kbuild.

Bugzilla: https://bugzilla.opensuse.org/show_bug.cgi?id=988117
Fixes: a92ea59b74e2 ('ASoC: Intel: sst: only select sst-firmware when DW DMAC is built-in')
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

1 files changed, 68 insertions, 0 deletions

diff --git a/sound/soc/intel/common/sst-firmware.c b/sound/soc/intel/common/sst-firmware.c
index 25993527370b..a086c35f91bb 100644
--- a/sound/soc/intel/common/sst-firmware.c
+++ b/sound/soc/intel/common/sst-firmware.c
@@ -1211,3 +1211,71 @@ u32 sst_dsp_get_offset(struct sst_dsp *dsp, u32 offset,
 	}
 }
 EXPORT_SYMBOL_GPL(sst_dsp_get_offset);
+
+struct sst_dsp *sst_dsp_new(struct device *dev,
+	struct sst_dsp_device *sst_dev, struct sst_pdata *pdata)
+{
+	struct sst_dsp *sst;
+	int err;
+
+	dev_dbg(dev, "initialising audio DSP id 0x%x\n", pdata->id);
+
+	sst = devm_kzalloc(dev, sizeof(*sst), GFP_KERNEL);
+	if (sst == NULL)
+		return NULL;
+
+	spin_lock_init(&sst->spinlock);
+	mutex_init(&sst->mutex);
+	sst->dev = dev;
+	sst->dma_dev = pdata->dma_dev;
+	sst->thread_context = sst_dev->thread_context;
+	sst->sst_dev = sst_dev;
+	sst->id = pdata->id;
+	sst->irq = pdata->irq;
+	sst->ops = sst_dev->ops;
+	sst->pdata = pdata;
+	INIT_LIST_HEAD(&sst->used_block_list);
+	INIT_LIST_HEAD(&sst->free_block_list);
+	INIT_LIST_HEAD(&sst->module_list);
+	INIT_LIST_HEAD(&sst->fw_list);
+	INIT_LIST_HEAD(&sst->scratch_block_list);
+
+	/* Initialise SST Audio DSP */
+	if (sst->ops->init) {
+		err = sst->ops->init(sst, pdata);
+		if (err < 0)
+			return NULL;
+	}
+
+	/* Register the ISR */
+	err = request_threaded_irq(sst->irq, sst->ops->irq_handler,
+		sst_dev->thread, IRQF_SHARED, "AudioDSP", sst);
+	if (err)
+		goto irq_err;
+
+	err = sst_dma_new(sst);
+	if (err)
+		dev_warn(dev, "sst_dma_new failed %d\n", err);
+
+	return sst;
+
+irq_err:
+	if (sst->ops->free)
+		sst->ops->free(sst);
+
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(sst_dsp_new);
+
+void sst_dsp_free(struct sst_dsp *sst)
+{
+	free_irq(sst->irq, sst);
+	if (sst->ops->free)
+		sst->ops->free(sst);
+
+	sst_dma_free(sst->dma);
+}
+EXPORT_SYMBOL_GPL(sst_dsp_free);
+
+MODULE_DESCRIPTION("Intel SST Firmware Loader");
+MODULE_LICENSE("GPL v2");