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

John Keeping
2016-05-03T09:43:18Z

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@rock-chips.com>:
> > 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@metanate.com>:
> >>>>
> >>>> 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@metanate.com>
> >>>> ---
> >>>> 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 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():

-- >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@metanate.com>
---
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