From: Alexey Klimov alexey.klimov@linaro.org
[ Upstream commit 107a5c853eef5336a9846e7dd2f9184b6e3c07c7 ]
On a system with wcd937x, rxmacro and Qualcomm audio DSP, which is pretty common set of devices on Qualcomm platforms, and due to the order of how DAPM widgets are powered on (they are sorted), there is a small time window when wcd937x chip is online and expects the flow of incoming data but rxmacro is not yet online. When wcd937x is programmed to receive data via AUX port then its AUX PDM watchdog is enabled in wcd937x_codec_enable_aux_pa(). If due to some reasons the rxmacro and soundwire machinery are delayed to start streaming data, then there is a chance for this AUX PDM watchdog to reset the wcd937x codec. Such event is not logged as a message and only wcd937x IRQ counter is increased however there could be a lot of other reasons for that IRQ. There is a similar opportunity for such delay during DAPM widgets power down sequence.
If wcd937x codec reset happens on the start of the playback, then there will be no sound and if such reset happens at the end of a playback then it may generate additional clicks and pops noises.
On qrb4210 RB2 board without any debugging bits the wcd937x resets are sometimes observed at the end of a playback though not always. With some debugging messages or with some tracing enabled the AUX PDM watchdog resets the wcd937x codec at the start of a playback and there is no sound output at all.
In this patch: - TIMEOUT_SEL bit in PDM_WD_CTL2 register is set to increase the watchdog reset delay to 100ms which eliminates the AUX PDM watchdog IRQs on qrb4210 RB2 board completely and decreases the number of unwanted clicks noises;
- HOLD_OFF bit postpones triggering such watchdog IRQ till wcd937x codec reset which usually happens at the end of a playback. This allows to actually output some sound in case of debugging.
Cc: Adam Skladowski a39.skl@gmail.com Cc: Mohammad Rafi Shaik quic_mohs@quicinc.com Cc: Prasad Kumpatla quic_pkumpatl@quicinc.com Cc: Srinivas Kandagatla srinivas.kandagatla@linaro.org Signed-off-by: Alexey Klimov alexey.klimov@linaro.org Link: https://patch.msgid.link/20241022033132.787416-3-alexey.klimov@linaro.org Signed-off-by: Mark Brown broonie@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- sound/soc/codecs/wcd937x.c | 10 ++++++++-- sound/soc/codecs/wcd937x.h | 4 ++++ 2 files changed, 12 insertions(+), 2 deletions(-)
diff --git a/sound/soc/codecs/wcd937x.c b/sound/soc/codecs/wcd937x.c index 63b25c321a03d..3c1224d8f2dff 100644 --- a/sound/soc/codecs/wcd937x.c +++ b/sound/soc/codecs/wcd937x.c @@ -715,12 +715,17 @@ static int wcd937x_codec_enable_aux_pa(struct snd_soc_dapm_widget *w, struct snd_soc_component *component = snd_soc_dapm_to_component(w->dapm); struct wcd937x_priv *wcd937x = snd_soc_component_get_drvdata(component); int hph_mode = wcd937x->hph_mode; + u8 val;
switch (event) { case SND_SOC_DAPM_PRE_PMU: + val = WCD937X_DIGITAL_PDM_WD_CTL2_EN | + WCD937X_DIGITAL_PDM_WD_CTL2_TIMEOUT_SEL | + WCD937X_DIGITAL_PDM_WD_CTL2_HOLD_OFF; snd_soc_component_update_bits(component, WCD937X_DIGITAL_PDM_WD_CTL2, - BIT(0), BIT(0)); + WCD937X_DIGITAL_PDM_WD_CTL2_MASK, + val); break; case SND_SOC_DAPM_POST_PMU: usleep_range(1000, 1010); @@ -741,7 +746,8 @@ static int wcd937x_codec_enable_aux_pa(struct snd_soc_dapm_widget *w, hph_mode); snd_soc_component_update_bits(component, WCD937X_DIGITAL_PDM_WD_CTL2, - BIT(0), 0x00); + WCD937X_DIGITAL_PDM_WD_CTL2_MASK, + 0x00); break; }
diff --git a/sound/soc/codecs/wcd937x.h b/sound/soc/codecs/wcd937x.h index 37bff16e88ddd..a2bd47a93e507 100644 --- a/sound/soc/codecs/wcd937x.h +++ b/sound/soc/codecs/wcd937x.h @@ -391,6 +391,10 @@ #define WCD937X_DIGITAL_PDM_WD_CTL0 0x3465 #define WCD937X_DIGITAL_PDM_WD_CTL1 0x3466 #define WCD937X_DIGITAL_PDM_WD_CTL2 0x3467 +#define WCD937X_DIGITAL_PDM_WD_CTL2_HOLD_OFF BIT(2) +#define WCD937X_DIGITAL_PDM_WD_CTL2_TIMEOUT_SEL BIT(1) +#define WCD937X_DIGITAL_PDM_WD_CTL2_EN BIT(0) +#define WCD937X_DIGITAL_PDM_WD_CTL2_MASK GENMASK(2, 0) #define WCD937X_DIGITAL_INTR_MODE 0x346A #define WCD937X_DIGITAL_INTR_MASK_0 0x346B #define WCD937X_DIGITAL_INTR_MASK_1 0x346C