> On 5 Dec 2021, at 10:08 pm, Martin Blumenstingl <martin.blumenstingl@xxxxxxxxxxxxxx> wrote: > > The out-of-tree vendor driver uses the following approach to set the > AIU_I2S_MISC register: > 1) write AIU_MEM_I2S_START_PTR and AIU_MEM_I2S_RD_PTR > 2) configure AIU_I2S_MUTE_SWAP[15:0] > 3) write AIU_MEM_I2S_END_PTR > 4) set AIU_I2S_MISC[2] to 1 (documented as: "put I2S interface in hold > mode") > 5) set AIU_I2S_MISC[4] to 1 (depending on the driver revision it always > stays at 1 while for older drivers this bit is unset in step 4) > 6) set AIU_I2S_MISC[2] to 0 > 7) write AIU_MEM_I2S_MASKS > 8) toggle AIU_MEM_I2S_CONTROL[0] > 9) toggle AIU_MEM_I2S_BUF_CNTL[0] > > Additional testing shows that when AIU_I2S_MISC[2] is set to 1 then no > interrupts are generated anymore. The way this bit is managed by the > vendor driver as well as not getting any interrupts can mean that it's > related to the FIFO and not the encoder. > > Move setting the AIU_I2S_MISC[2] bit to aiu_fifo_i2s_hw_params() so it > closer resembles the flow in the vendor kernel. While here also > configure AIU_I2S_MISC[4] (documented as: "force each audio data to > left or right according to the bit attached with the audio data") > similar to how the vendor driver does this. This fixes the infamous and > long-standing "machine gun noise" issue (a buffer underrun issue). > > Fixes: 6ae9ca9ce986bf ("ASoC: meson: aiu: add i2s and spdif support") > Reported-by: Christian Hewitt <christianshewitt@xxxxxxxxx> > Reported-by: Geraldo Nascimento <geraldogabriel@xxxxxxxxx> > Signed-off-by: Martin Blumenstingl <martin.blumenstingl@xxxxxxxxxxxxxx> Thanks Martin. Checked with WeTek Play 2 (GXBB), LePotato (GXL), and Khadas VIM2 (GXM) so I’m delighted to say: Tested-by: Christian Hewitt <christianshewitt@xxxxxxxxx> > --- > sound/soc/meson/aiu-encoder-i2s.c | 33 ------------------------------- > sound/soc/meson/aiu-fifo-i2s.c | 12 +++++++++++ > 2 files changed, 12 insertions(+), 33 deletions(-) > > diff --git a/sound/soc/meson/aiu-encoder-i2s.c b/sound/soc/meson/aiu-encoder-i2s.c > index 932224552146..67729de41a73 100644 > --- a/sound/soc/meson/aiu-encoder-i2s.c > +++ b/sound/soc/meson/aiu-encoder-i2s.c > @@ -18,7 +18,6 @@ > #define AIU_RST_SOFT_I2S_FAST BIT(0) > > #define AIU_I2S_DAC_CFG_MSB_FIRST BIT(2) > -#define AIU_I2S_MISC_HOLD_EN BIT(2) > #define AIU_CLK_CTRL_I2S_DIV_EN BIT(0) > #define AIU_CLK_CTRL_I2S_DIV GENMASK(3, 2) > #define AIU_CLK_CTRL_AOCLK_INVERT BIT(6) > @@ -36,37 +35,6 @@ static void aiu_encoder_i2s_divider_enable(struct snd_soc_component *component, > enable ? AIU_CLK_CTRL_I2S_DIV_EN : 0); > } > > -static void aiu_encoder_i2s_hold(struct snd_soc_component *component, > - bool enable) > -{ > - snd_soc_component_update_bits(component, AIU_I2S_MISC, > - AIU_I2S_MISC_HOLD_EN, > - enable ? AIU_I2S_MISC_HOLD_EN : 0); > -} > - > -static int aiu_encoder_i2s_trigger(struct snd_pcm_substream *substream, int cmd, > - struct snd_soc_dai *dai) > -{ > - struct snd_soc_component *component = dai->component; > - > - switch (cmd) { > - case SNDRV_PCM_TRIGGER_START: > - case SNDRV_PCM_TRIGGER_RESUME: > - case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: > - aiu_encoder_i2s_hold(component, false); > - return 0; > - > - case SNDRV_PCM_TRIGGER_STOP: > - case SNDRV_PCM_TRIGGER_SUSPEND: > - case SNDRV_PCM_TRIGGER_PAUSE_PUSH: > - aiu_encoder_i2s_hold(component, true); > - return 0; > - > - default: > - return -EINVAL; > - } > -} > - > static int aiu_encoder_i2s_setup_desc(struct snd_soc_component *component, > struct snd_pcm_hw_params *params) > { > @@ -353,7 +321,6 @@ static void aiu_encoder_i2s_shutdown(struct snd_pcm_substream *substream, > } > > const struct snd_soc_dai_ops aiu_encoder_i2s_dai_ops = { > - .trigger = aiu_encoder_i2s_trigger, > .hw_params = aiu_encoder_i2s_hw_params, > .hw_free = aiu_encoder_i2s_hw_free, > .set_fmt = aiu_encoder_i2s_set_fmt, > diff --git a/sound/soc/meson/aiu-fifo-i2s.c b/sound/soc/meson/aiu-fifo-i2s.c > index 2388a2d0b3a6..d0a1090d6465 100644 > --- a/sound/soc/meson/aiu-fifo-i2s.c > +++ b/sound/soc/meson/aiu-fifo-i2s.c > @@ -20,6 +20,8 @@ > #define AIU_MEM_I2S_CONTROL_MODE_16BIT BIT(6) > #define AIU_MEM_I2S_BUF_CNTL_INIT BIT(0) > #define AIU_RST_SOFT_I2S_FAST BIT(0) > +#define AIU_I2S_MISC_HOLD_EN BIT(2) > +#define AIU_I2S_MISC_FORCE_LEFT_RIGHT BIT(4) > > #define AIU_FIFO_I2S_BLOCK 256 > > @@ -90,6 +92,10 @@ static int aiu_fifo_i2s_hw_params(struct snd_pcm_substream *substream, > unsigned int val; > int ret; > > + snd_soc_component_update_bits(component, AIU_I2S_MISC, > + AIU_I2S_MISC_HOLD_EN, > + AIU_I2S_MISC_HOLD_EN); > + > ret = aiu_fifo_hw_params(substream, params, dai); > if (ret) > return ret; > @@ -117,6 +123,12 @@ static int aiu_fifo_i2s_hw_params(struct snd_pcm_substream *substream, > snd_soc_component_update_bits(component, AIU_MEM_I2S_MASKS, > AIU_MEM_I2S_MASKS_IRQ_BLOCK, val); > > + snd_soc_component_update_bits(component, AIU_I2S_MISC, > + AIU_I2S_MISC_FORCE_LEFT_RIGHT, > + AIU_I2S_MISC_FORCE_LEFT_RIGHT); > + snd_soc_component_update_bits(component, AIU_I2S_MISC, > + AIU_I2S_MISC_HOLD_EN, 0); > + > return 0; > } > > -- > 2.34.1 >