[PATCH] ASoC: fsl_sai: Enable transmitter when generating MCLK
For SAI to generate MCLK on external SoC pad, the transmitter must be enabled as well. With transmitter disabled, no clock are generated. Enable the transmitter using the TERE bit. Signed-off-by: Marek Vasut <marex@denx.de> --- Cc: Fabio Estevam <festevam@gmail.com> Cc: Jaroslav Kysela <perex@perex.cz> Cc: Liam Girdwood <lgirdwood@gmail.com> Cc: Mark Brown <broonie@kernel.org> Cc: Nicolin Chen <nicoleotsuka@gmail.com> Cc: Shengjiu Wang <shengjiu.wang@gmail.com> Cc: Takashi Iwai <tiwai@suse.com> Cc: Xiubo Li <Xiubo.Lee@gmail.com> To: alsa-devel@alsa-project.org --- sound/soc/fsl/fsl_sai.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/sound/soc/fsl/fsl_sai.c b/sound/soc/fsl/fsl_sai.c index 1c9be8a5dcb13..98c62027e5799 100644 --- a/sound/soc/fsl/fsl_sai.c +++ b/sound/soc/fsl/fsl_sai.c @@ -503,6 +503,10 @@ static int fsl_sai_set_bclk(struct snd_soc_dai *dai, bool tx, u32 freq) /* SAI is in master mode at this point, so enable MCLK */ regmap_update_bits(sai->regmap, FSL_SAI_MCTL, FSL_SAI_MCTL_MCLK_EN, FSL_SAI_MCTL_MCLK_EN); + + /* Transmitter must be enabled to generate MCLK on pad */ + regmap_update_bits(sai->regmap, FSL_SAI_xCSR(1, ofs), + FSL_SAI_CSR_TERE, FSL_SAI_CSR_TERE); } return 0; @@ -1445,6 +1449,11 @@ static int fsl_sai_probe(struct platform_device *pdev) sai->soc_data->max_register >= FSL_SAI_MCTL) { regmap_update_bits(sai->regmap, FSL_SAI_MCTL, FSL_SAI_MCTL_MCLK_EN, FSL_SAI_MCTL_MCLK_EN); + + /* Transmitter must be enabled to generate MCLK on pad */ + regmap_update_bits(sai->regmap, + FSL_SAI_xCSR(1, sai->soc_data->reg_offset), + FSL_SAI_CSR_TERE, FSL_SAI_CSR_TERE); } ret = pm_runtime_put_sync(dev); -- 2.35.1
On Tue, Nov 8, 2022 at 5:52 AM Marek Vasut <marex@denx.de> wrote:
For SAI to generate MCLK on external SoC pad, the transmitter must be enabled as well. With transmitter disabled, no clock are generated. Enable the transmitter using the TERE bit.
It is already done in trigger(), why need to do this operation in probe() and set_bclk() again? best regards wang shengjiu
Signed-off-by: Marek Vasut <marex@denx.de> --- Cc: Fabio Estevam <festevam@gmail.com> Cc: Jaroslav Kysela <perex@perex.cz> Cc: Liam Girdwood <lgirdwood@gmail.com> Cc: Mark Brown <broonie@kernel.org> Cc: Nicolin Chen <nicoleotsuka@gmail.com> Cc: Shengjiu Wang <shengjiu.wang@gmail.com> Cc: Takashi Iwai <tiwai@suse.com> Cc: Xiubo Li <Xiubo.Lee@gmail.com> To: alsa-devel@alsa-project.org --- sound/soc/fsl/fsl_sai.c | 9 +++++++++ 1 file changed, 9 insertions(+)
diff --git a/sound/soc/fsl/fsl_sai.c b/sound/soc/fsl/fsl_sai.c index 1c9be8a5dcb13..98c62027e5799 100644 --- a/sound/soc/fsl/fsl_sai.c +++ b/sound/soc/fsl/fsl_sai.c @@ -503,6 +503,10 @@ static int fsl_sai_set_bclk(struct snd_soc_dai *dai, bool tx, u32 freq) /* SAI is in master mode at this point, so enable MCLK */ regmap_update_bits(sai->regmap, FSL_SAI_MCTL, FSL_SAI_MCTL_MCLK_EN, FSL_SAI_MCTL_MCLK_EN); + + /* Transmitter must be enabled to generate MCLK on pad */ + regmap_update_bits(sai->regmap, FSL_SAI_xCSR(1, ofs), + FSL_SAI_CSR_TERE, FSL_SAI_CSR_TERE); }
return 0; @@ -1445,6 +1449,11 @@ static int fsl_sai_probe(struct platform_device *pdev) sai->soc_data->max_register >= FSL_SAI_MCTL) { regmap_update_bits(sai->regmap, FSL_SAI_MCTL, FSL_SAI_MCTL_MCLK_EN, FSL_SAI_MCTL_MCLK_EN); + + /* Transmitter must be enabled to generate MCLK on pad */ + regmap_update_bits(sai->regmap, + FSL_SAI_xCSR(1, sai->soc_data->reg_offset), + FSL_SAI_CSR_TERE, FSL_SAI_CSR_TERE); }
ret = pm_runtime_put_sync(dev); -- 2.35.1
On 11/8/22 06:29, Shengjiu Wang wrote:
On Tue, Nov 8, 2022 at 5:52 AM Marek Vasut <marex@denx.de> wrote:
For SAI to generate MCLK on external SoC pad, the transmitter must be enabled as well. With transmitter disabled, no clock are generated. Enable the transmitter using the TERE bit.
It is already done in trigger(), why need to do this operation in probe() and set_bclk() again?
The system I have here has SAI MCLK (output) connected to SGTL5000 codec MCLK (input) . If the SAI MCLK (output), the codec I2C interface won't work. That's why the MCLK must be enabled so early.
On Tue, Nov 8, 2022 at 5:52 AM Marek Vasut <marex@denx.de> wrote:
For SAI to generate MCLK on external SoC pad, the transmitter must be enabled as well. With transmitter disabled, no clock are generated. Enable the transmitter using the TERE bit.
Signed-off-by: Marek Vasut <marex@denx.de> --- Cc: Fabio Estevam <festevam@gmail.com> Cc: Jaroslav Kysela <perex@perex.cz> Cc: Liam Girdwood <lgirdwood@gmail.com> Cc: Mark Brown <broonie@kernel.org> Cc: Nicolin Chen <nicoleotsuka@gmail.com> Cc: Shengjiu Wang <shengjiu.wang@gmail.com> Cc: Takashi Iwai <tiwai@suse.com> Cc: Xiubo Li <Xiubo.Lee@gmail.com> To: alsa-devel@alsa-project.org --- sound/soc/fsl/fsl_sai.c | 9 +++++++++ 1 file changed, 9 insertions(+)
diff --git a/sound/soc/fsl/fsl_sai.c b/sound/soc/fsl/fsl_sai.c index 1c9be8a5dcb13..98c62027e5799 100644 --- a/sound/soc/fsl/fsl_sai.c +++ b/sound/soc/fsl/fsl_sai.c @@ -503,6 +503,10 @@ static int fsl_sai_set_bclk(struct snd_soc_dai *dai, bool tx, u32 freq) /* SAI is in master mode at this point, so enable MCLK */ regmap_update_bits(sai->regmap, FSL_SAI_MCTL, FSL_SAI_MCTL_MCLK_EN, FSL_SAI_MCTL_MCLK_EN); + + /* Transmitter must be enabled to generate MCLK on pad */ + regmap_update_bits(sai->regmap, FSL_SAI_xCSR(1, ofs), + FSL_SAI_CSR_TERE, FSL_SAI_CSR_TERE);
No need to fix the transmitter, FSL_SAI_xCSR(tx, ofs) should work also.
}
return 0; @@ -1445,6 +1449,11 @@ static int fsl_sai_probe(struct platform_device *pdev) sai->soc_data->max_register >= FSL_SAI_MCTL) { regmap_update_bits(sai->regmap, FSL_SAI_MCTL, FSL_SAI_MCTL_MCLK_EN, FSL_SAI_MCTL_MCLK_EN); + + /* Transmitter must be enabled to generate MCLK on pad */ + regmap_update_bits(sai->regmap, + FSL_SAI_xCSR(1, sai->soc_data->reg_offset), + FSL_SAI_CSR_TERE, FSL_SAI_CSR_TERE);
After one time playback or recording, the TERE is disabled, so this changes in probe() only for the first time. There is the same issue for the second time. best regards wang shengjiu
}
ret = pm_runtime_put_sync(dev); -- 2.35.1
On 11/9/22 10:30, Shengjiu Wang wrote: [...]
diff --git a/sound/soc/fsl/fsl_sai.c b/sound/soc/fsl/fsl_sai.c index 1c9be8a5dcb13..98c62027e5799 100644 --- a/sound/soc/fsl/fsl_sai.c +++ b/sound/soc/fsl/fsl_sai.c @@ -503,6 +503,10 @@ static int fsl_sai_set_bclk(struct snd_soc_dai *dai, bool tx, u32 freq) /* SAI is in master mode at this point, so enable MCLK */ regmap_update_bits(sai->regmap, FSL_SAI_MCTL, FSL_SAI_MCTL_MCLK_EN, FSL_SAI_MCTL_MCLK_EN); + + /* Transmitter must be enabled to generate MCLK on pad */ + regmap_update_bits(sai->regmap, FSL_SAI_xCSR(1, ofs), + FSL_SAI_CSR_TERE, FSL_SAI_CSR_TERE);
No need to fix the transmitter, FSL_SAI_xCSR(tx, ofs) should work also.
That's probably not a good idea, since this could also enable the RE(receiver) part . We always need to enable the TE(transmitter) to generate MCLK.
}
return 0; @@ -1445,6 +1449,11 @@ static int fsl_sai_probe(struct platform_device *pdev) sai->soc_data->max_register >= FSL_SAI_MCTL) { regmap_update_bits(sai->regmap, FSL_SAI_MCTL, FSL_SAI_MCTL_MCLK_EN, FSL_SAI_MCTL_MCLK_EN); + + /* Transmitter must be enabled to generate MCLK on pad */ + regmap_update_bits(sai->regmap, + FSL_SAI_xCSR(1, sai->soc_data->reg_offset), + FSL_SAI_CSR_TERE, FSL_SAI_CSR_TERE);
After one time playback or recording, the TERE is disabled, so this changes in probe() only for the first time. There is the same issue for the second time.
So what would you suggest to keep the MCLK clock generated always ? I was almost tempted to turn the SAI into a clock provider, so that the codec could become its clock consumer and enable the MCLK on demand, but that seems to be a rather invasive change.
On Wed, Nov 9, 2022 at 8:55 PM Marek Vasut <marex@denx.de> wrote:
On 11/9/22 10:30, Shengjiu Wang wrote:
[...]
diff --git a/sound/soc/fsl/fsl_sai.c b/sound/soc/fsl/fsl_sai.c index 1c9be8a5dcb13..98c62027e5799 100644 --- a/sound/soc/fsl/fsl_sai.c +++ b/sound/soc/fsl/fsl_sai.c @@ -503,6 +503,10 @@ static int fsl_sai_set_bclk(struct snd_soc_dai *dai, bool tx, u32 freq) /* SAI is in master mode at this point, so enable MCLK */ regmap_update_bits(sai->regmap, FSL_SAI_MCTL, FSL_SAI_MCTL_MCLK_EN, FSL_SAI_MCTL_MCLK_EN); + + /* Transmitter must be enabled to generate MCLK on pad */ + regmap_update_bits(sai->regmap, FSL_SAI_xCSR(1, ofs), + FSL_SAI_CSR_TERE, FSL_SAI_CSR_TERE);
No need to fix the transmitter, FSL_SAI_xCSR(tx, ofs) should work also.
That's probably not a good idea, since this could also enable the RE(receiver) part . We always need to enable the TE(transmitter) to generate MCLK.
TCSR.TERE and RCSR.TERE all can enable the MCLK. if use the FSL_SAI_xCSR(tx, ofs), both cases can be covered. if the bclk is generated by TX, then enable the TE(transmitter) to generate MCLK. or if the bclk is generated by RX, then enable the RE(receiver) to generate MCLK.
}
return 0; @@ -1445,6 +1449,11 @@ static int fsl_sai_probe(struct platform_device *pdev) sai->soc_data->max_register >= FSL_SAI_MCTL) { regmap_update_bits(sai->regmap, FSL_SAI_MCTL, FSL_SAI_MCTL_MCLK_EN, FSL_SAI_MCTL_MCLK_EN); + + /* Transmitter must be enabled to generate MCLK on pad
*/
+ regmap_update_bits(sai->regmap, + FSL_SAI_xCSR(1, sai->soc_data->reg_offset), + FSL_SAI_CSR_TERE, FSL_SAI_CSR_TERE);
After one time playback or recording, the TERE is disabled, so this changes in probe() only for the first time. There is the same issue for the second time.
So what would you suggest to keep the MCLK clock generated always ?
I was almost tempted to turn the SAI into a clock provider, so that the codec could become its clock consumer and enable the MCLK on demand, but that seems to be a rather invasive change.
May you can try to enhance the drivers/clk/clk-fsl-sai.c best regards wang shengjiu
On 11/14/22 08:55, Shengjiu Wang wrote:
On Wed, Nov 9, 2022 at 8:55 PM Marek Vasut <marex@denx.de> wrote:
On 11/9/22 10:30, Shengjiu Wang wrote:
[...]
diff --git a/sound/soc/fsl/fsl_sai.c b/sound/soc/fsl/fsl_sai.c index 1c9be8a5dcb13..98c62027e5799 100644 --- a/sound/soc/fsl/fsl_sai.c +++ b/sound/soc/fsl/fsl_sai.c @@ -503,6 +503,10 @@ static int fsl_sai_set_bclk(struct snd_soc_dai *dai, bool tx, u32 freq) /* SAI is in master mode at this point, so enable MCLK */ regmap_update_bits(sai->regmap, FSL_SAI_MCTL, FSL_SAI_MCTL_MCLK_EN, FSL_SAI_MCTL_MCLK_EN); + + /* Transmitter must be enabled to generate MCLK on pad */ + regmap_update_bits(sai->regmap, FSL_SAI_xCSR(1, ofs), + FSL_SAI_CSR_TERE, FSL_SAI_CSR_TERE);
No need to fix the transmitter, FSL_SAI_xCSR(tx, ofs) should work also.
That's probably not a good idea, since this could also enable the RE(receiver) part . We always need to enable the TE(transmitter) to generate MCLK.
TCSR.TERE and RCSR.TERE all can enable the MCLK. if use the FSL_SAI_xCSR(tx, ofs), both cases can be covered. if the bclk is generated by TX, then enable the TE(transmitter) to generate MCLK. or if the bclk is generated by RX, then enable the RE(receiver) to generate MCLK.
I will need to do a full re-test to validate this claim.
@@ -1445,6 +1449,11 @@ static int fsl_sai_probe(struct platform_device *pdev) sai->soc_data->max_register >= FSL_SAI_MCTL) { regmap_update_bits(sai->regmap, FSL_SAI_MCTL, FSL_SAI_MCTL_MCLK_EN, FSL_SAI_MCTL_MCLK_EN); + + /* Transmitter must be enabled to generate MCLK on pad */ + regmap_update_bits(sai->regmap, + FSL_SAI_xCSR(1, sai->soc_data->reg_offset), + FSL_SAI_CSR_TERE, FSL_SAI_CSR_TERE);
After one time playback or recording, the TERE is disabled, so this changes in probe() only for the first time. There is the same issue for the second time.
So what would you suggest to keep the MCLK clock generated always ?
I was almost tempted to turn the SAI into a clock provider, so that the codec could become its clock consumer and enable the MCLK on demand, but that seems to be a rather invasive change.
May you can try to enhance the drivers/clk/clk-fsl-sai.c
This is not really useful in this case, this lets users use the SAI as a plain clock source. I use the SAI as audio IP, all I need in addition to that is enable the MCLK as codec Master Clock to drive the codec register file and whatever internal state it has.
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Shengjiu Wang