ASoC: aw88399: fix BSTS check using vendor driver logic

Marco Giunta <marco_giunta@outlook.it> says:

The aw88399 sysst check requires BSTS (boost finished) to assert during
startup. On hardware where the boost converter is bypassed via external
power supply (EN_HVBAT in BSTCTRL10, i.e. register 0x69 bit 2), BSTS never
asserts and init fails.

The vendor's generic Android driver (aw883xx, [1]) handles this by reading
EN_HVBAT and conditionally skipping the BSTS check.
When the original aw88399 driver was ported to the in-tree ASoC driver,
this logic was not included.

During the development of the HDA side codec driver, I worked around this
with a per-instance bsts_unreliable flag set from the HDA scodec
driver's per-model quirk table. While functional, this approach requires
every new device where the boost converter is bypassed to carry a quirk
entry, and prevents users from testing the driver on such devices via the
model= alc269 module parameter without a custom kernel to add the entry.

This series adds the correct hardware-based check from the vendor driver
(patch 1) and removes the now-unnecessary workaround (patch 2),
simplifying the code and removing a barrier to testing on new devices.

[1] https://www.awinic.com/en/driver/AW88399QNR/594

Link: https://patch.msgid.link/SN6PR19MB230304C2E75499FE23B53885FC8F2@SN6PR19MB2303.namprd19.prod.outlook.com

4 files changed, 24 insertions, 39 deletions

diff --git a/include/sound/aw88399.h b/include/sound/aw88399.h
index a1e0de6be8ea..38d9bd6abd8b 100644
--- a/include/sound/aw88399.h
+++ b/include/sound/aw88399.h
@@ -449,6 +449,11 @@
 #define AW88399_NOISE_GATE_EN_MASK	\
 	(~(((1<<AW88399_NOISE_GATE_EN_BITS_LEN)-1) << AW88399_NOISE_GATE_EN_START_BIT))
 
+#define AW88399_EPS_EN_START_BIT	(2)
+#define AW88399_EPS_EN_BITS_LEN		(1)
+#define AW88399_EPS_EN_MASK		\
+	(~(((1 << AW88399_EPS_EN_BITS_LEN) - 1) << AW88399_EPS_EN_START_BIT))
+
 #define AW88399_WDT_CNT_START_BIT	(0)
 #define AW88399_WDT_CNT_BITS_LEN	(8)
 #define AW88399_WDT_CNT_MASK		\
@@ -598,7 +603,6 @@ struct aw88399 {
 	unsigned int crc_init_val;
 	unsigned int vcalb_init_val;
 	unsigned int dither_st;
-	bool bsts_unreliable;
 	bool fw_needs_reload;
 };
 
diff --git a/sound/hda/codecs/side-codecs/aw88399_hda.c b/sound/hda/codecs/side-codecs/aw88399_hda.c
index 11cef4923024..69d113af8ae3 100644
--- a/sound/hda/codecs/side-codecs/aw88399_hda.c
+++ b/sound/hda/codecs/side-codecs/aw88399_hda.c
@@ -118,7 +118,6 @@ static int aw88399_hda_init(struct aw88399_hda *aw88399)
 	mutex_init(&core->lock);
 	core->reset_gpio = aw88399->reset_gpio;
 	core->regmap = aw88399->regmap;
-	core->bsts_unreliable = aw88399->bsts_unreliable;
 
 	aw88399_hw_reset(core);
 
@@ -155,41 +154,20 @@ static int aw88399_swap_channels(struct aw88399_hda *aw88399)
 	return 0;
 }
 
-static int aw88399_skip_bsts_check(struct aw88399_hda *aw88399)
-{
-	/*
-	 * BSTS (boost-finished) status bit does not reliably report on
-	 * some hardware. On certain Lenovo Legion laptops, both amps
-	 * report BSTS=0 (boost not finished) during normal playback
-	 * despite clean audio output. Skip BSTS in the startup status
-	 * check to avoid false init failures.
-	 */
-	aw88399->bsts_unreliable = true;
-	dev_dbg(aw88399->dev, "BSTS status check disabled\n");
-	return 0;
-}
-
-static int aw88399_apply_legion_quirks(struct aw88399_hda *aw88399)
-{
-	aw88399_swap_channels(aw88399);
-	aw88399_skip_bsts_check(aw88399);
-	return 0;
-}
-
 struct aw88399_prop_model {
 	const char *ssid;
 	int (*apply_prop)(struct aw88399_hda *aw88399);
 };
 
 static const struct aw88399_prop_model aw88399_prop_model_table[] = {
-	{ "17AA3906", aw88399_apply_legion_quirks },
-	{ "17AA3907", aw88399_apply_legion_quirks },
-	{ "17AA3927", aw88399_apply_legion_quirks },
-	{ "17AA3928", aw88399_apply_legion_quirks },
-	{ "17AA3936", aw88399_apply_legion_quirks },
-	{ "17AA3937", aw88399_apply_legion_quirks },
-	{ "17AA3938", aw88399_apply_legion_quirks },
-	{ "17AA3939", aw88399_apply_legion_quirks },
+	{ "17AA3906", aw88399_swap_channels },
+	{ "17AA3907", aw88399_swap_channels },
+	{ "17AA3927", aw88399_swap_channels },
+	{ "17AA3928", aw88399_swap_channels },
+	{ "17AA3936", aw88399_swap_channels },
+	{ "17AA3937", aw88399_swap_channels },
+	{ "17AA3938", aw88399_swap_channels },
+	{ "17AA3939", aw88399_swap_channels },
 	{ }
 };
 
diff --git a/sound/hda/codecs/side-codecs/aw88399_hda.h b/sound/hda/codecs/side-codecs/aw88399_hda.h
index ca0aa5279298..af71083124bd 100644
--- a/sound/hda/codecs/side-codecs/aw88399_hda.h
+++ b/sound/hda/codecs/side-codecs/aw88399_hda.h
@@ -19,7 +19,6 @@ struct aw88399_hda {
 	struct gpio_desc *reset_gpio;
 	struct aw_device *aw_dev;
 	struct aw88399 *core;
-	bool bsts_unreliable;
 
 	const char *acpi_subsystem_id;
 	int index;
diff --git a/sound/soc/codecs/aw88399-lib.c b/sound/soc/codecs/aw88399-lib.c
index 809c2faa0c0c..75a533c9b752 100644
--- a/sound/soc/codecs/aw88399-lib.c
+++ b/sound/soc/codecs/aw88399-lib.c
@@ -167,9 +167,8 @@ int aw_dev_check_syspll(struct aw_device *aw_dev)
 }
 EXPORT_SYMBOL_GPL(aw_dev_check_syspll);
 
-static int aw_dev_check_sysst(struct aw88399 *aw88399)
+static int aw_dev_check_sysst(struct aw_device *aw_dev)
 {
-	struct aw_device *aw_dev = aw88399->aw_pa;
 	unsigned int check_val;
 	unsigned int reg_val;
 	int ret, i;
@@ -184,11 +183,16 @@ static int aw_dev_check_sysst(struct aw88399 *aw88399)
 		check_val = AW88399_BIT_SYSST_SWS_CHECK;
 
 	/*
-	 * On some hardware the BSTS (boost-finished) status bit does not
-	 * reliably assert even when audio output is working normally.
-	 * Allow per-instance bypass when flagged by the side-codec driver.
+	 * When an external power supply (EPS) is used to feed the amplifier
+	 * (EN_HVBAT bit in BSTCTRL10 set), the boost converter is bypassed,
+	 * and BSTS (boost finished) will never assert. Skip the BSTS check in
+	 * this case, matching the vendor driver's behavior.
 	 */
-	if (aw88399->bsts_unreliable)
+	ret = regmap_read(aw_dev->regmap, AW88399_BSTCTRL10_REG, &reg_val);
+	if (ret)
+		return ret;
+
+	if (reg_val & (~AW88399_EPS_EN_MASK))
 		check_val &= ~AW88399_BSTS_FINISHED_VALUE;
 
 	for (i = 0; i < AW88399_DEV_SYSST_CHECK_MAX; i++) {
@@ -719,7 +723,7 @@ static int aw88399_dev_start(struct aw88399 *aw88399)
 	usleep_range(AW88399_1000_US, AW88399_1000_US + 50);
 
 	/* check i2s status */
-	ret = aw_dev_check_sysst(aw88399);
+	ret = aw_dev_check_sysst(aw_dev);
 	if (ret) {
 		dev_err(aw_dev->dev, "sysst check failed");
 		goto sysst_check_fail;