lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

ASoC: DaVinci: i2s, only start sample generator if needed

Browse Source 
Only start sample generator if needed, and more
cleanup on davinci_mcbsp_start.

Signed-off-by: Troy Kisky <troy.kisky@boundarydevices.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
This commit is contained in:
Troy Kisky
2009-07-04 19:29:55 -07:00
committed by Mark Brown
parent eba575c30b
commit 1bef449989
1 changed files with 14 additions and 18 deletions
Download Patch File Download Diff File Expand all files Collapse all files

26
sound/soc/davinci/davinci-i2s.c
View File

@@ -146,11 +146,14 @@ static void davinci_mcbsp_start(struct davinci_mcbsp_dev *dev,
spcr & ~mask); spcr & ~mask);
toggle_clock(dev, playback); toggle_clock(dev, playback);
} }
/* Start the sample generator and enable transmitter/receiver */ if (dev->pcr & (DAVINCI_MCBSP_PCR_FSXM | DAVINCI_MCBSP_PCR_FSRM |
DAVINCI_MCBSP_PCR_CLKXM | DAVINCI_MCBSP_PCR_CLKRM)) {
/* Start the sample generator */
spcr |= DAVINCI_MCBSP_SPCR_GRST; spcr |= DAVINCI_MCBSP_SPCR_GRST;
davinci_mcbsp_write_reg(dev, DAVINCI_MCBSP_SPCR_REG, spcr); davinci_mcbsp_write_reg(dev, DAVINCI_MCBSP_SPCR_REG, spcr);
}
if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) { if (playback) {
/* Stop the DMA to avoid data loss */ /* Stop the DMA to avoid data loss */
/* while the transmitter is out of reset to handle XSYNCERR */ /* while the transmitter is out of reset to handle XSYNCERR */
if (platform->pcm_ops->trigger) { if (platform->pcm_ops->trigger) {
@@ -181,23 +184,16 @@ static void davinci_mcbsp_start(struct davinci_mcbsp_dev *dev,
if (ret < 0) if (ret < 0)
printk(KERN_DEBUG "Playback DMA start failed\n"); printk(KERN_DEBUG "Playback DMA start failed\n");
} }
/* Enable the transmitter */
spcr = davinci_mcbsp_read_reg(dev, DAVINCI_MCBSP_SPCR_REG);
spcr |= DAVINCI_MCBSP_SPCR_XRST;
davinci_mcbsp_write_reg(dev, DAVINCI_MCBSP_SPCR_REG, spcr);
} else {
/* Enable the reciever */
spcr = davinci_mcbsp_read_reg(dev, DAVINCI_MCBSP_SPCR_REG);
spcr |= DAVINCI_MCBSP_SPCR_RRST;
davinci_mcbsp_write_reg(dev, DAVINCI_MCBSP_SPCR_REG, spcr);
} }
/* Enable transmitter or receiver */
/* Start frame sync */
spcr = davinci_mcbsp_read_reg(dev, DAVINCI_MCBSP_SPCR_REG); spcr = davinci_mcbsp_read_reg(dev, DAVINCI_MCBSP_SPCR_REG);
spcr |= mask;
if (dev->pcr & (DAVINCI_MCBSP_PCR_FSXM | DAVINCI_MCBSP_PCR_FSRM)) {
/* Start frame sync */
spcr |= DAVINCI_MCBSP_SPCR_FRST; spcr |= DAVINCI_MCBSP_SPCR_FRST;
}
davinci_mcbsp_write_reg(dev, DAVINCI_MCBSP_SPCR_REG, spcr); davinci_mcbsp_write_reg(dev, DAVINCI_MCBSP_SPCR_REG, spcr);
} }