Skip to content

Commit

Permalink
ASoC: rockchip: i2s: switch BCLK to GPIO
Browse files Browse the repository at this point in the history 
We discoverd that the state of BCLK on, LRCLK off and SD_MODE on
may cause the speaker melting issue. Removing LRCLK while BCLK
is present can cause unexpected output behavior including a large
DC output voltage as described in the Max98357a datasheet.

In order to:
  1. prevent BCLK from turning on by other component.
  2. keep BCLK and LRCLK being present at the same time

This patch switches BCLK to GPIO func before LRCLK output, and
configures BCLK func back during LRCLK is output.

Without this fix, BCLK is turned on 11 ms earlier than LRCK by the
da7219.
With this fix, BCLK is turned on only 0.4 ms earlier than LRCK by
the rockchip codec.

Signed-off-by: Judy Hsiao <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Mark Brown <[email protected]>
  • Loading branch information
@broonie
Judy Hsiao authored and broonie committed Jun 24, 2022
1 parent 3911535 commit a5450ab
Showing 1 changed file with 129 additions and 31 deletions.
160 changes: 129 additions & 31 deletions sound/soc/rockchip/rockchip_i2s.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -13,6 +13,7 @@
#include <linux/of_gpio.h>
#include <linux/of_device.h>
#include <linux/clk.h>
#include <linux/pinctrl/consumer.h>
#include <linux/pm_runtime.h>
#include <linux/regmap.h>
#include <linux/spinlock.h>
Expand Down Expand Up @@ -54,8 +55,40 @@ struct rk_i2s_dev {
const struct rk_i2s_pins *pins;
unsigned int bclk_ratio;
spinlock_t lock; /* tx/rx lock */
struct pinctrl *pinctrl;
struct pinctrl_state *bclk_on;
struct pinctrl_state *bclk_off;
};

static int i2s_pinctrl_select_bclk_on(struct rk_i2s_dev *i2s)
{
int ret = 0;

if (!IS_ERR(i2s->pinctrl) && !IS_ERR_OR_NULL(i2s->bclk_on))
ret = pinctrl_select_state(i2s->pinctrl,
i2s->bclk_on);

if (ret)
dev_err(i2s->dev, "bclk enable failed %d\n", ret);

return ret;
}

static int i2s_pinctrl_select_bclk_off(struct rk_i2s_dev *i2s)
{

int ret = 0;

if (!IS_ERR(i2s->pinctrl) && !IS_ERR_OR_NULL(i2s->bclk_off))
ret = pinctrl_select_state(i2s->pinctrl,
i2s->bclk_off);

if (ret)
dev_err(i2s->dev, "bclk disable failed %d\n", ret);

return ret;
}

static int i2s_runtime_suspend(struct device *dev)
{
struct rk_i2s_dev *i2s = dev_get_drvdata(dev);
Expand Down Expand Up @@ -92,38 +125,49 @@ static inline struct rk_i2s_dev *to_info(struct snd_soc_dai *dai)
return snd_soc_dai_get_drvdata(dai);
}

static void rockchip_snd_txctrl(struct rk_i2s_dev *i2s, int on)
static int rockchip_snd_txctrl(struct rk_i2s_dev *i2s, int on)
{
unsigned int val = 0;
int retry = 10;
int ret = 0;

spin_lock(&i2s->lock);
if (on) {
regmap_update_bits(i2s->regmap, I2S_DMACR,
I2S_DMACR_TDE_ENABLE, I2S_DMACR_TDE_ENABLE);
ret = regmap_update_bits(i2s->regmap, I2S_DMACR,
I2S_DMACR_TDE_ENABLE, I2S_DMACR_TDE_ENABLE);
if (ret < 0)
goto end;

regmap_update_bits(i2s->regmap, I2S_XFER,
I2S_XFER_TXS_START | I2S_XFER_RXS_START,
I2S_XFER_TXS_START | I2S_XFER_RXS_START);
ret = regmap_update_bits(i2s->regmap, I2S_XFER,
I2S_XFER_TXS_START | I2S_XFER_RXS_START,
I2S_XFER_TXS_START | I2S_XFER_RXS_START);
if (ret < 0)
goto end;

i2s->tx_start = true;
} else {
i2s->tx_start = false;

regmap_update_bits(i2s->regmap, I2S_DMACR,
I2S_DMACR_TDE_ENABLE, I2S_DMACR_TDE_DISABLE);
ret = regmap_update_bits(i2s->regmap, I2S_DMACR,
I2S_DMACR_TDE_ENABLE, I2S_DMACR_TDE_DISABLE);
if (ret < 0)
goto end;

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);
ret = regmap_update_bits(i2s->regmap, I2S_XFER,
I2S_XFER_TXS_START |
I2S_XFER_RXS_START,
I2S_XFER_TXS_STOP |
I2S_XFER_RXS_STOP);
if (ret < 0)
goto end;

udelay(150);
regmap_update_bits(i2s->regmap, I2S_CLR,
I2S_CLR_TXC | I2S_CLR_RXC,
I2S_CLR_TXC | I2S_CLR_RXC);
ret = regmap_update_bits(i2s->regmap, I2S_CLR,
I2S_CLR_TXC | I2S_CLR_RXC,
I2S_CLR_TXC | I2S_CLR_RXC);
if (ret < 0)
goto end;

regmap_read(i2s->regmap, I2S_CLR, &val);

Expand All @@ -138,44 +182,57 @@ static void rockchip_snd_txctrl(struct rk_i2s_dev *i2s, int on)
}
}
}
end:
spin_unlock(&i2s->lock);
if (ret < 0)
dev_err(i2s->dev, "lrclk update failed\n");

return ret;
}

static void rockchip_snd_rxctrl(struct rk_i2s_dev *i2s, int on)
static int rockchip_snd_rxctrl(struct rk_i2s_dev *i2s, int on)
{
unsigned int val = 0;
int retry = 10;
int ret = 0;

spin_lock(&i2s->lock);
if (on) {
regmap_update_bits(i2s->regmap, I2S_DMACR,
ret = regmap_update_bits(i2s->regmap, I2S_DMACR,
I2S_DMACR_RDE_ENABLE, I2S_DMACR_RDE_ENABLE);
if (ret < 0)
goto end;

regmap_update_bits(i2s->regmap, I2S_XFER,
ret = regmap_update_bits(i2s->regmap, I2S_XFER,
I2S_XFER_TXS_START | I2S_XFER_RXS_START,
I2S_XFER_TXS_START | I2S_XFER_RXS_START);
if (ret < 0)
goto end;

i2s->rx_start = true;
} else {
i2s->rx_start = false;

regmap_update_bits(i2s->regmap, I2S_DMACR,
ret = regmap_update_bits(i2s->regmap, I2S_DMACR,
I2S_DMACR_RDE_ENABLE, I2S_DMACR_RDE_DISABLE);
if (ret < 0)
goto end;

if (!i2s->tx_start) {
regmap_update_bits(i2s->regmap, I2S_XFER,
ret = regmap_update_bits(i2s->regmap, I2S_XFER,
I2S_XFER_TXS_START |
I2S_XFER_RXS_START,
I2S_XFER_TXS_STOP |
I2S_XFER_RXS_STOP);

if (ret < 0)
goto end;
udelay(150);
regmap_update_bits(i2s->regmap, I2S_CLR,
ret = regmap_update_bits(i2s->regmap, I2S_CLR,
I2S_CLR_TXC | I2S_CLR_RXC,
I2S_CLR_TXC | I2S_CLR_RXC);

if (ret < 0)
goto end;
regmap_read(i2s->regmap, I2S_CLR, &val);

/* Should wait for clear operation to finish */
while (val) {
regmap_read(i2s->regmap, I2S_CLR, &val);
Expand All @@ -187,7 +244,12 @@ static void rockchip_snd_rxctrl(struct rk_i2s_dev *i2s, int on)
}
}
}
end:
spin_unlock(&i2s->lock);
if (ret < 0)
dev_err(i2s->dev, "lrclk update failed\n");

return ret;
}

static int rockchip_i2s_set_fmt(struct snd_soc_dai *cpu_dai,
Expand Down Expand Up @@ -425,17 +487,26 @@ static int rockchip_i2s_trigger(struct snd_pcm_substream *substream,
case SNDRV_PCM_TRIGGER_RESUME:
case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
rockchip_snd_rxctrl(i2s, 1);
ret = rockchip_snd_rxctrl(i2s, 1);
else
rockchip_snd_txctrl(i2s, 1);
ret = rockchip_snd_txctrl(i2s, 1);
/* Do not turn on bclk if lrclk open fails. */
if (ret < 0)
return ret;
i2s_pinctrl_select_bclk_on(i2s);
break;
case SNDRV_PCM_TRIGGER_SUSPEND:
case SNDRV_PCM_TRIGGER_STOP:
case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
rockchip_snd_rxctrl(i2s, 0);
else
rockchip_snd_txctrl(i2s, 0);
if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) {
if (!i2s->tx_start)
i2s_pinctrl_select_bclk_off(i2s);
ret = rockchip_snd_rxctrl(i2s, 0);
} else {
if (!i2s->rx_start)
i2s_pinctrl_select_bclk_off(i2s);
ret = rockchip_snd_txctrl(i2s, 0);
}
break;
default:
ret = -EINVAL;
Expand Down Expand Up @@ -736,6 +807,33 @@ static int rockchip_i2s_probe(struct platform_device *pdev)
}

i2s->bclk_ratio = 64;
i2s->pinctrl = devm_pinctrl_get(&pdev->dev);
if (IS_ERR(i2s->pinctrl))
dev_err(&pdev->dev, "failed to find i2s pinctrl\n");

i2s->bclk_on = pinctrl_lookup_state(i2s->pinctrl,
"bclk_on");
if (IS_ERR_OR_NULL(i2s->bclk_on))
dev_err(&pdev->dev, "failed to find i2s default state\n");
else
dev_dbg(&pdev->dev, "find i2s bclk state\n");

i2s->bclk_off = pinctrl_lookup_state(i2s->pinctrl,
"bclk_off");
if (IS_ERR_OR_NULL(i2s->bclk_off))
dev_err(&pdev->dev, "failed to find i2s gpio state\n");
else
dev_dbg(&pdev->dev, "find i2s bclk_off state\n");

i2s_pinctrl_select_bclk_off(i2s);

i2s->playback_dma_data.addr = res->start + I2S_TXDR;
i2s->playback_dma_data.addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
i2s->playback_dma_data.maxburst = 4;

i2s->capture_dma_data.addr = res->start + I2S_RXDR;
i2s->capture_dma_data.addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
i2s->capture_dma_data.maxburst = 4;

dev_set_drvdata(&pdev->dev, i2s);

Expand Down

0 comments on commit a5450ab

Please sign in to comment.