[PATCH 3/5 v4] ASoC: dwc: Use fifo depth to program FCR

From: Jose Abreu
Date: Thu Apr 07 2016 - 12:55:50 EST


This patch makes Designware I2S driver use the fifo
depth value to program the fifo configuration register
instead of using hardcoded values.

Signed-off-by: Jose Abreu <joabreu@xxxxxxxxxxxx>
---

This patch was only introduced in v4.

sound/soc/dwc/designware_i2s.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/sound/soc/dwc/designware_i2s.c b/sound/soc/dwc/designware_i2s.c
index 3effcd1..0db69b7 100644
--- a/sound/soc/dwc/designware_i2s.c
+++ b/sound/soc/dwc/designware_i2s.c
@@ -100,6 +100,7 @@ struct dw_i2s_dev {
struct device *dev;
u32 ccr;
u32 xfer_resolution;
+ u32 fifo_th;

/* data related to DMA transfers b/w i2s and DMAC */
union dw_i2s_snd_dma_data play_dma_data;
@@ -232,14 +233,16 @@ static void dw_i2s_config(struct dw_i2s_dev *dev, int stream)
if (stream == SNDRV_PCM_STREAM_PLAYBACK) {
i2s_write_reg(dev->i2s_base, TCR(ch_reg),
dev->xfer_resolution);
- i2s_write_reg(dev->i2s_base, TFCR(ch_reg), 0x02);
+ i2s_write_reg(dev->i2s_base, TFCR(ch_reg),
+ dev->fifo_th - 1);
irq = i2s_read_reg(dev->i2s_base, IMR(ch_reg));
i2s_write_reg(dev->i2s_base, IMR(ch_reg), irq & ~0x30);
i2s_write_reg(dev->i2s_base, TER(ch_reg), 1);
} else {
i2s_write_reg(dev->i2s_base, RCR(ch_reg),
dev->xfer_resolution);
- i2s_write_reg(dev->i2s_base, RFCR(ch_reg), 0x07);
+ i2s_write_reg(dev->i2s_base, RFCR(ch_reg),
+ dev->fifo_th - 1);
irq = i2s_read_reg(dev->i2s_base, IMR(ch_reg));
i2s_write_reg(dev->i2s_base, IMR(ch_reg), irq & ~0x03);
i2s_write_reg(dev->i2s_base, RER(ch_reg), 1);
@@ -499,6 +502,7 @@ static int dw_configure_dai(struct dw_i2s_dev *dev,
*/
u32 comp1 = i2s_read_reg(dev->i2s_base, dev->i2s_reg_comp1);
u32 comp2 = i2s_read_reg(dev->i2s_base, dev->i2s_reg_comp2);
+ u32 fifo_depth = 1 << (1 + COMP1_FIFO_DEPTH_GLOBAL(comp1));
u32 idx;

if (dev->capability & DWC_I2S_RECORD &&
@@ -537,6 +541,7 @@ static int dw_configure_dai(struct dw_i2s_dev *dev,
dev->capability |= DW_I2S_SLAVE;
}

+ dev->fifo_th = fifo_depth / 2;
return 0;
}

--
1.9.1