[PATCH v3] ASoc: tas2781: Enable RCA-based playback without DSP firmware download

[Shenghao Ding <shenghao-ding@ti.com>]

In only RCA(Reconfigurable Architecture) binary case, no DSP program will
be working inside tas2563/tas2781, that is dsp-bypass mode, do not support
speaker protection, and audio acoustic algorithms in this mode.

Fixes: ef3bcde75d06 ("ASoC: tas2781: Add tas2781 driver")
Signed-off-by: Shenghao Ding <shenghao-ding@ti.com>

---
v3:
 - Add description on RCA is Reconfigurable Architecture.
 - Add the description on enabling
 - Reword the commit
 - Remove question mark in the comments.
 - Add spaces in comments.
v2:
 - Correct comment.
 - Add Fixes.
 - Move header file to the first.
v1:
 - Split out the different logical changes into different patches.
 - rename tasdevice_dsp_fw_state -> tasdevice_fw_state, the fw are not
   only DSP fw, but also RCA(Reconfigurable data, such as acoustic data
   and register setting, etc).
 - Add TASDEVICE_RCA_FW_OK in tasdevice_fw_state to identify the state
   that only RCA binary file has been download successfully, but DSP fw
   is not loaded or loading failure.
 - Add the this strategy into tasdevice_tuning_switch.
 - If one side of the if/else has a braces both should in
   tasdevice_tuning_switch.
 - Identify whehter both RCA and DSP have been loaded or only RCA has
   been loaded in tasdevice_fw_ready.
 - Add check fw load status in tasdevice_startup.
 - remove ret in tasdevice_startup to make the code neater.
---
 include/sound/tas2781-dsp.h       |  3 ++-
 sound/soc/codecs/tas2781-fmwlib.c | 16 ++++++++++-----
 sound/soc/codecs/tas2781-i2c.c    | 33 ++++++++++++++++++++-----------
 3 files changed, 34 insertions(+), 18 deletions(-)

diff --git a/include/sound/tas2781-dsp.h b/include/sound/tas2781-dsp.h
index 7fba7ea26a4b..92d68ca5eafb 100644
--- a/include/sound/tas2781-dsp.h
+++ b/include/sound/tas2781-dsp.h
@@ -117,10 +117,11 @@ struct tasdevice_fw {
 	struct device *dev;
 };
 
-enum tasdevice_dsp_fw_state {
+enum tasdevice_fw_state {
 	TASDEVICE_DSP_FW_NONE = 0,
 	TASDEVICE_DSP_FW_PENDING,
 	TASDEVICE_DSP_FW_FAIL,
+	TASDEVICE_RCA_FW_OK,
 	TASDEVICE_DSP_FW_ALL_OK,
 };
 
diff --git a/sound/soc/codecs/tas2781-fmwlib.c b/sound/soc/codecs/tas2781-fmwlib.c
index 265a8ca25cbb..5db1a0ac6036 100644
--- a/sound/soc/codecs/tas2781-fmwlib.c
+++ b/sound/soc/codecs/tas2781-fmwlib.c
@@ -2324,14 +2324,19 @@ void tasdevice_tuning_switch(void *context, int state)
 	struct tasdevice_fw *tas_fmw = tas_priv->fmw;
 	int profile_cfg_id = tas_priv->rcabin.profile_cfg_id;
 
-	if (tas_priv->fw_state == TASDEVICE_DSP_FW_FAIL) {
-		dev_err(tas_priv->dev, "DSP bin file not loaded\n");
+	/*
+	 * Only RCA-based Playback can still work with no dsp program running
+	 * inside the chip?
+	 */
+	if (!(tas_priv->fw_state == TASDEVICE_RCA_FW_OK ||
+		tas_priv->fw_state == TASDEVICE_DSP_FW_ALL_OK)) {
+		dev_err(tas_priv->dev, "No firmware loaded\n");
 		return;
 	}
 
 	if (state == 0) {
-		if (tas_priv->cur_prog < tas_fmw->nr_programs) {
-			/*dsp mode or tuning mode*/
+		if (tas_fmw && tas_priv->cur_prog < tas_fmw->nr_programs) {
+			/* dsp mode or tuning mode */
 			profile_cfg_id = tas_priv->rcabin.profile_cfg_id;
 			tasdevice_select_tuningprm_cfg(tas_priv,
 				tas_priv->cur_prog, tas_priv->cur_conf,
@@ -2340,9 +2345,10 @@ void tasdevice_tuning_switch(void *context, int state)
 
 		tasdevice_select_cfg_blk(tas_priv, profile_cfg_id,
 			TASDEVICE_BIN_BLK_PRE_POWER_UP);
-	} else
+	} else {
 		tasdevice_select_cfg_blk(tas_priv, profile_cfg_id,
 			TASDEVICE_BIN_BLK_PRE_SHUTDOWN);
+	}
 }
 EXPORT_SYMBOL_NS_GPL(tasdevice_tuning_switch,
 	SND_SOC_TAS2781_FMWLIB);
diff --git a/sound/soc/codecs/tas2781-i2c.c b/sound/soc/codecs/tas2781-i2c.c
index 9350972dfefe..9b85a44511c2 100644
--- a/sound/soc/codecs/tas2781-i2c.c
+++ b/sound/soc/codecs/tas2781-i2c.c
@@ -380,23 +380,33 @@ static void tasdevice_fw_ready(const struct firmware *fmw,
 	mutex_lock(&tas_priv->codec_lock);
 
 	ret = tasdevice_rca_parser(tas_priv, fmw);
-	if (ret)
+	if (ret) {
+		tasdevice_config_info_remove(tas_priv);
 		goto out;
+	}
 	tasdevice_create_control(tas_priv);
 
 	tasdevice_dsp_remove(tas_priv);
 	tasdevice_calbin_remove(tas_priv);
-	tas_priv->fw_state = TASDEVICE_DSP_FW_PENDING;
+	tas_priv->fw_state = TASDEVICE_RCA_FW_OK;
 	scnprintf(tas_priv->coef_binaryname, 64, "%s_coef.bin",
 		tas_priv->dev_name);
+
 	ret = tasdevice_dsp_parser(tas_priv);
 	if (ret) {
 		dev_err(tas_priv->dev, "dspfw load %s error\n",
 			tas_priv->coef_binaryname);
-		tas_priv->fw_state = TASDEVICE_DSP_FW_FAIL;
 		goto out;
 	}
-	tasdevice_dsp_create_ctrls(tas_priv);
+
+	/*
+	 * If no dsp-related kcontrol created, the dsp resource will be freed.
+	 */
+	ret = tasdevice_dsp_create_ctrls(tas_priv);
+	if (ret) {
+		dev_err(tas_priv->dev, "dsp controls error\n");
+		goto out;
+	}
 
 	tas_priv->fw_state = TASDEVICE_DSP_FW_ALL_OK;
 
@@ -417,9 +427,8 @@ static void tasdevice_fw_ready(const struct firmware *fmw,
 	tasdevice_prmg_load(tas_priv, 0);
 	tas_priv->cur_prog = 0;
 out:
-	if (tas_priv->fw_state == TASDEVICE_DSP_FW_FAIL) {
-		/*If DSP FW fail, kcontrol won't be created */
-		tasdevice_config_info_remove(tas_priv);
+	if (tas_priv->fw_state == TASDEVICE_RCA_FW_OK) {
+		/*If DSP FW fail, DSP kcontrol won't be created */
 		tasdevice_dsp_remove(tas_priv);
 	}
 	mutex_unlock(&tas_priv->codec_lock);
@@ -466,14 +475,14 @@ static int tasdevice_startup(struct snd_pcm_substream *substream,
 {
 	struct snd_soc_component *codec = dai->component;
 	struct tasdevice_priv *tas_priv = snd_soc_component_get_drvdata(codec);
-	int ret = 0;
 
-	if (tas_priv->fw_state != TASDEVICE_DSP_FW_ALL_OK) {
-		dev_err(tas_priv->dev, "DSP bin file not loaded\n");
-		ret = -EINVAL;
+	if (!(tas_priv->fw_state == TASDEVICE_DSP_FW_ALL_OK ||
+		tas_priv->fw_state == TASDEVICE_RCA_FW_OK)) {
+		dev_err(tas_priv->dev, "Bin file not loaded\n");
+		return -EINVAL;
 	}
 
-	return ret;
+	return 0;
 }
 
 static int tasdevice_hw_params(struct snd_pcm_substream *substream,
-- 
2.34.1