ASoC: cs35l56: Must clear HALO_STATE before issuing SYSTEM_RESET

[ Upstream commit e33625c84b75e4f078d7f9bf58f01fe71ab99642 ]

The driver must write 0 to HALO_STATE before sending the SYSTEM_RESET
command to the firmware.

HALO_STATE is in DSP memory, which is preserved across a soft reset.
The SYSTEM_RESET command does not change the value of HALO_STATE.
There is period of time while the CS35L56 is resetting, before the
firmware has started to boot, where a read of HALO_STATE will return
the value it had before the SYSTEM_RESET. If the driver does not
clear HALO_STATE, this would return BOOT_DONE status even though the
firmware has not booted.

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Fixes: 8a731fd37f8b ("ASoC: cs35l56: Move utility functions to shared file")
Link: https://msgid.link/r/20240216140535.1434933-1-rf@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/sound/soc/codecs/cs35l56-shared.c b/sound/soc/codecs/cs35l56-shared.c
index 98b1e63360aeb3a5cbd277a328fd28b7393ea01b..a925701f46fc6f0a21a6883678d518bfd92b23ef 100644 (file)
--- a/sound/soc/codecs/cs35l56-shared.c
+++ b/sound/soc/codecs/cs35l56-shared.c
@@ -286,6 +286,7 @@ void cs35l56_wait_min_reset_pulse(void)
 EXPORT_SYMBOL_NS_GPL(cs35l56_wait_min_reset_pulse, SND_SOC_CS35L56_SHARED);
 
 static const struct reg_sequence cs35l56_system_reset_seq[] = {
+       REG_SEQ0(CS35L56_DSP1_HALO_STATE, 0),
        REG_SEQ0(CS35L56_DSP_VIRTUAL1_MBOX_1, CS35L56_MBOX_CMD_SYSTEM_RESET),
 };