ASoC: qcom: Fix building APQ8016 machine driver without SOUNDWIRE

Older Qualcomm platforms like APQ8016 do not have hardware support for
SoundWire, so kernel configurations made specifically for those platforms
will usually not have CONFIG_SOUNDWIRE enabled.

Unfortunately commit 8d89cf6ff229 ("ASoC: qcom: cleanup and fix
dependency of QCOM_COMMON") breaks those kernel configurations, because
SOUNDWIRE is now a required dependency for SND_SOC_QCOM_COMMON (and in
turn also SND_SOC_APQ8016_SBC). Trying to migrate such a kernel config
silently disables SND_SOC_APQ8016_SBC and breaks audio functionality.

The soundwire helpers in common.c are only used by two of the Qualcomm
audio machine drivers, so building and requiring CONFIG_SOUNDWIRE for
all platforms is unnecessary.

There is no need to stuff all common code into a single module. Fix the
issue by moving the soundwire helpers to a separate SND_SOC_QCOM_SDW
module/option that is selected only by the machine drivers that make
use of them. This also allows reverting the imply/depends changes from
the previous fix because both SM8250 and SC8280XP already depend on
SOUNDWIRE, so the soundwire helpers will be only built if SOUNDWIRE
is really enabled.

Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Fixes: 8d89cf6ff229 ("ASoC: qcom: cleanup and fix dependency of QCOM_COMMON")
Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
Link: https://lore.kernel.org/r/20221231115506.82991-1-stephan@gerhold.net
Signed-off-by: Mark Brown <broonie@kernel.org>

1 files changed, 123 insertions, 0 deletions

diff --git a/sound/soc/qcom/sdw.c b/sound/soc/qcom/sdw.c
new file mode 100644
index 000000000000..10249519a39e
--- /dev/null
+++ b/sound/soc/qcom/sdw.c
@@ -0,0 +1,123 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2018, Linaro Limited.
+// Copyright (c) 2018, The Linux Foundation. All rights reserved.
+
+#include <linux/module.h>
+#include <sound/soc.h>
+#include "qdsp6/q6afe.h"
+#include "sdw.h"
+
+int qcom_snd_sdw_prepare(struct snd_pcm_substream *substream,
+			 struct sdw_stream_runtime *sruntime,
+			 bool *stream_prepared)
+{
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct snd_soc_dai *cpu_dai = asoc_rtd_to_cpu(rtd, 0);
+	int ret;
+
+	if (!sruntime)
+		return 0;
+
+	switch (cpu_dai->id) {
+	case WSA_CODEC_DMA_RX_0:
+	case WSA_CODEC_DMA_RX_1:
+	case RX_CODEC_DMA_RX_0:
+	case RX_CODEC_DMA_RX_1:
+	case TX_CODEC_DMA_TX_0:
+	case TX_CODEC_DMA_TX_1:
+	case TX_CODEC_DMA_TX_2:
+	case TX_CODEC_DMA_TX_3:
+		break;
+	default:
+		return 0;
+	}
+
+	if (*stream_prepared) {
+		sdw_disable_stream(sruntime);
+		sdw_deprepare_stream(sruntime);
+		*stream_prepared = false;
+	}
+
+	ret = sdw_prepare_stream(sruntime);
+	if (ret)
+		return ret;
+
+	/**
+	 * NOTE: there is a strict hw requirement about the ordering of port
+	 * enables and actual WSA881x PA enable. PA enable should only happen
+	 * after soundwire ports are enabled if not DC on the line is
+	 * accumulated resulting in Click/Pop Noise
+	 * PA enable/mute are handled as part of codec DAPM and digital mute.
+	 */
+
+	ret = sdw_enable_stream(sruntime);
+	if (ret) {
+		sdw_deprepare_stream(sruntime);
+		return ret;
+	}
+	*stream_prepared  = true;
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(qcom_snd_sdw_prepare);
+
+int qcom_snd_sdw_hw_params(struct snd_pcm_substream *substream,
+			   struct snd_pcm_hw_params *params,
+			   struct sdw_stream_runtime **psruntime)
+{
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct snd_soc_dai *codec_dai;
+	struct snd_soc_dai *cpu_dai = asoc_rtd_to_cpu(rtd, 0);
+	struct sdw_stream_runtime *sruntime;
+	int i;
+
+	switch (cpu_dai->id) {
+	case WSA_CODEC_DMA_RX_0:
+	case RX_CODEC_DMA_RX_0:
+	case RX_CODEC_DMA_RX_1:
+	case TX_CODEC_DMA_TX_0:
+	case TX_CODEC_DMA_TX_1:
+	case TX_CODEC_DMA_TX_2:
+	case TX_CODEC_DMA_TX_3:
+		for_each_rtd_codec_dais(rtd, i, codec_dai) {
+			sruntime = snd_soc_dai_get_stream(codec_dai, substream->stream);
+			if (sruntime != ERR_PTR(-ENOTSUPP))
+				*psruntime = sruntime;
+		}
+		break;
+	}
+
+	return 0;
+
+}
+EXPORT_SYMBOL_GPL(qcom_snd_sdw_hw_params);
+
+int qcom_snd_sdw_hw_free(struct snd_pcm_substream *substream,
+			 struct sdw_stream_runtime *sruntime, bool *stream_prepared)
+{
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct snd_soc_dai *cpu_dai = asoc_rtd_to_cpu(rtd, 0);
+
+	switch (cpu_dai->id) {
+	case WSA_CODEC_DMA_RX_0:
+	case WSA_CODEC_DMA_RX_1:
+	case RX_CODEC_DMA_RX_0:
+	case RX_CODEC_DMA_RX_1:
+	case TX_CODEC_DMA_TX_0:
+	case TX_CODEC_DMA_TX_1:
+	case TX_CODEC_DMA_TX_2:
+	case TX_CODEC_DMA_TX_3:
+		if (sruntime && *stream_prepared) {
+			sdw_disable_stream(sruntime);
+			sdw_deprepare_stream(sruntime);
+			*stream_prepared = false;
+		}
+		break;
+	default:
+		break;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(qcom_snd_sdw_hw_free);
+MODULE_LICENSE("GPL v2");