Re: [alsa-devel] [PATCH 1/2] ASoC: rockchip: i2s: separate capture and playback

From: Enric Balletbo Serra
Date: Tue May 03 2016 - 06:21:30 EST

Hi John,

2016-05-03 11:43 GMT+02:00 John Keeping <john@xxxxxxxxxxxx>:
> Hi Enric,
>
> On Tue, 3 May 2016 11:16:58 +0200, Enric Balletbo Serra wrote:
>> 2016-05-03 6:12 GMT+02:00 sugar <sugar.zhang@xxxxxxxxxxxxxx>:
>> > On 4/30/2016 15:00, John Keeping Wrote:
>> >> On Fri, Apr 29, 2016 at 04:59:27PM +0200, Enric Balletbo Serra wrote:
>> >>>
>> >>> 2015-12-09 11:32 GMT+01:00 John Keeping <john@xxxxxxxxxxxx>:
>> >>>>
>> >>>> If we only clear the tx/rx state when both are disabled it is not
>> >>>> possible to start/stop one multiple times while the other is running.
>> >>>> Since the two are independently controlled, treat them as such and
>> >>>> remove the false dependency between capture and playback.
>> >>>>
>> >>>> Signed-off-by: John Keeping <john@xxxxxxxxxxxx>
>> >>>> ---
>> >>>> sound/soc/rockchip/rockchip_i2s.c | 72
>> >>>> +++++++++++++++++----------------------
>> >>>> 1 file changed, 32 insertions(+), 40 deletions(-)
>> >>>>
>> >>>> diff --git a/sound/soc/rockchip/rockchip_i2s.c
>> >>>> b/sound/soc/rockchip/rockchip_i2s.c
>> >>>> index 83b1b9c..acc6225 100644
>> >>>> --- a/sound/soc/rockchip/rockchip_i2s.c
>> >>>> +++ b/sound/soc/rockchip/rockchip_i2s.c
>> >>>> @@ -82,8 +82,8 @@ static void rockchip_snd_txctrl(struct rk_i2s_dev
>> >>>> *i2s, int on)
>> >>>> I2S_DMACR_TDE_ENABLE,
>> >>>> I2S_DMACR_TDE_ENABLE);
>> >>>>
>> >>>> regmap_update_bits(i2s->regmap, I2S_XFER,
>> >>>> - I2S_XFER_TXS_START |
>> >>>> I2S_XFER_RXS_START,
>> >>>> - I2S_XFER_TXS_START |
>> >>>> I2S_XFER_RXS_START);
>> >>>> + I2S_XFER_TXS_START,
>> >>>> + I2S_XFER_TXS_START);
>> >>>>
>> >>>> i2s->tx_start = true;
>> >>>> } else {
>> >>>> @@ -92,27 +92,23 @@ static void rockchip_snd_txctrl(struct rk_i2s_dev
>> >>>> *i2s, int on)
>> >>>> regmap_update_bits(i2s->regmap, I2S_DMACR,
>> >>>> I2S_DMACR_TDE_ENABLE,
>> >>>> I2S_DMACR_TDE_DISABLE);
>> >>>>
>> >>>> - if (!i2s->rx_start) {
>> >>>> - regmap_update_bits(i2s->regmap, I2S_XFER,
>> >>>> - I2S_XFER_TXS_START |
>> >>>> - I2S_XFER_RXS_START,
>> >>>> - I2S_XFER_TXS_STOP |
>> >>>> - I2S_XFER_RXS_STOP);
>> >>>> + regmap_update_bits(i2s->regmap, I2S_XFER,
>> >>>> + I2S_XFER_TXS_START,
>> >>>> + I2S_XFER_TXS_STOP);
>> >>>>
>> >>>> - regmap_update_bits(i2s->regmap, I2S_CLR,
>> >>>> - I2S_CLR_TXC | I2S_CLR_RXC,
>> >>>> - I2S_CLR_TXC | I2S_CLR_RXC);
>> >>>> + regmap_update_bits(i2s->regmap, I2S_CLR,
>> >>>> + I2S_CLR_TXC,
>> >>>> + I2S_CLR_TXC);
>> >>>>
>> >>>> - regmap_read(i2s->regmap, I2S_CLR, &val);
>> >>>> + regmap_read(i2s->regmap, I2S_CLR, &val);
>> >>>>
>> >>>> - /* Should wait for clear operation to finish */
>> >>>> - while (val) {
>> >>>> - regmap_read(i2s->regmap, I2S_CLR, &val);
>> >>>> - retry--;
>> >>>> - if (!retry) {
>> >>>> - dev_warn(i2s->dev, "fail to
>> >>>> clear\n");
>> >>>> - break;
>> >>>> - }
>> >>>> + /* Should wait for clear operation to finish */
>> >>>> + while (val & I2S_CLR_TXC) {
>> >>>> + regmap_read(i2s->regmap, I2S_CLR, &val);
>> >>>> + retry--;
>> >>>> + if (!retry) {
>> >>>> + dev_warn(i2s->dev, "fail to clear\n");
>> >>>> + break;
>> >>>> }
>> >>>> }
>> >>>> }
>> >>>> @@ -128,8 +124,8 @@ static void rockchip_snd_rxctrl(struct rk_i2s_dev
>> >>>> *i2s, int on)
>> >>>> I2S_DMACR_RDE_ENABLE,
>> >>>> I2S_DMACR_RDE_ENABLE);
>> >>>>
>> >>>> regmap_update_bits(i2s->regmap, I2S_XFER,
>> >>>> - I2S_XFER_TXS_START |
>> >>>> I2S_XFER_RXS_START,
>> >>>> - I2S_XFER_TXS_START |
>> >>>> I2S_XFER_RXS_START);
>> >>>> + I2S_XFER_RXS_START,
>> >>>> + I2S_XFER_RXS_START);
>> >>>>
>> >>>> i2s->rx_start = true;
>> >>>> } else {
>> >>>> @@ -138,27 +134,23 @@ static void rockchip_snd_rxctrl(struct rk_i2s_dev
>> >>>> *i2s, int on)
>> >>>> regmap_update_bits(i2s->regmap, I2S_DMACR,
>> >>>> I2S_DMACR_RDE_ENABLE,
>> >>>> I2S_DMACR_RDE_DISABLE);
>> >>>>
>> >>>> - if (!i2s->tx_start) {
>> >>>> - regmap_update_bits(i2s->regmap, I2S_XFER,
>> >>>> - I2S_XFER_TXS_START |
>> >>>> - I2S_XFER_RXS_START,
>> >>>> - I2S_XFER_TXS_STOP |
>> >>>> - I2S_XFER_RXS_STOP);
>> >>>> + regmap_update_bits(i2s->regmap, I2S_XFER,
>> >>>> + I2S_XFER_RXS_START,
>> >>>> + I2S_XFER_RXS_STOP);
>> >>>>
>> >>>> - regmap_update_bits(i2s->regmap, I2S_CLR,
>> >>>> - I2S_CLR_TXC | I2S_CLR_RXC,
>> >>>> - I2S_CLR_TXC | I2S_CLR_RXC);
>> >>>> + regmap_update_bits(i2s->regmap, I2S_CLR,
>> >>>> + I2S_CLR_RXC,
>> >>>> + I2S_CLR_RXC);
>> >>>>
>> >>>> - regmap_read(i2s->regmap, I2S_CLR, &val);
>> >>>> + regmap_read(i2s->regmap, I2S_CLR, &val);
>> >>>>
>> >>>> - /* Should wait for clear operation to finish */
>> >>>> - while (val) {
>> >>>> - regmap_read(i2s->regmap, I2S_CLR, &val);
>> >>>> - retry--;
>> >>>> - if (!retry) {
>> >>>> - dev_warn(i2s->dev, "fail to
>> >>>> clear\n");
>> >>>> - break;
>> >>>> - }
>> >>>> + /* Should wait for clear operation to finish */
>> >>>> + while (val & I2S_CLR_RXC) {
>> >>>> + regmap_read(i2s->regmap, I2S_CLR, &val);
>> >>>> + retry--;
>> >>>> + if (!retry) {
>> >>>> + dev_warn(i2s->dev, "fail to clear\n");
>> >>>> + break;
>> >>>> }
>> >>>> }
>> >>>> }
>> >>>> --
>> >>>> 2.6.3.462.gbe2c914
>> >>>
>> >>>
>> >>> Using my Veyron Jerry Chromebook wiht latest kernel I found that the
>> >>> speakers doesn't work. Bisect points to this patch as the offending
>> >>> commit. However your changes looks reasonable the fact is that
>> >>> reverting the patch makes the audio work again on my device. I need to
>> >>> dig a bit more into the issue, but meanwhile, any idea on what is
>> >>> happening ? Can I ask which device did you test?
>> >>
>> >>
>> >> I tested this on a Radxa Rock2 square. This change fixed an issue I
>> >> found when running separate processes for playback and recording (I was
>> >> testing with arecord and speaker-test IIRC) but I don't think that
>> >> should be relevant. I just read through the patch again and I can't see
>> >> anything obviously wrong so I'm afraid I don't have any idea what's
>> >> causing the problem you're seeing.
>> >>
>> > Do you have test playback/capture at the same time? I think you may
>> > reproduce this issue if you do as follows:
>> >
>> > step 1: tinyplay test.wav -D 0 -d 0 -p 1024 -n 4 &
>> > step 2: tinycap r.wav -D 0 -d 0 -p 1024 -n 4 &
>> >
>> > you will find that there is no music now.
>> >
>> > because of this problem, we enable tx/rx at the same time to WA this issue.
>> >
>>
>> I can confirm that reverting John's patch audio playback/capture at
>> the same time works on my Veyron Jerry Chromebook.
>
> Have you tried stopping one of the processes and then starting it again
> (without touching the other process)? That's the case that was broken
> for me without this patch.
>

I just tried that and it works on my platform. Meanwhile I reproduced
a song I recorded two wavs.

> I have had a quick look through the code I'm using and I noticed that I
> have another change that hasn't been sent upstream, which marks the
> I2S_FIFOLR register as volatile in rockchip_i2s_volatile_reg():
>

Unfortunately that didn't help, I hear nothing from the speakers :(

I have a Radxa Rock2 Square board, by chance, do you have a git tree
containing the patches to enable the i2s sound for radxa so I can
reproduce both here? At least the codec is not upstreamed, I guess.

> -- >8 --
> Subject: [PATCH] ASoC: rockchip: i2s: mark FIFOLR register volatile
>
> The FIFO levels will be updated by the device so they should not be
> cached.
>
> Signed-off-by: John Keeping <john@xxxxxxxxxxxx>
> ---
> sound/soc/rockchip/rockchip_i2s.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/sound/soc/rockchip/rockchip_i2s.c b/sound/soc/rockchip/rockchip_i2s.c
> index d78f4c925b02..b517d8abcc40 100644
> --- a/sound/soc/rockchip/rockchip_i2s.c
> +++ b/sound/soc/rockchip/rockchip_i2s.c
> @@ -434,6 +434,7 @@ static bool rockchip_i2s_volatile_reg(struct device *dev, unsigned int reg)
> switch (reg) {
> case I2S_INTSR:
> case I2S_CLR:
> + case I2S_FIFOLR:
> return true;
> default:
> return false;
> -- 8< --
>
>
> Regards,
> John