[PATCH] ASoC: davinci-mcasp: Clear TXSTAT register before activating serializers
From: Peter Ujfalusi
Date: Fri Nov 16 2018 - 08:41:38 EST
Follow the guideline from the TRM:
Before starting, clear the respective transmitter and receiver status
registers
To avoid stale state stored in the status registers.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@xxxxxx>
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
---
sound/soc/davinci/davinci-mcasp.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/sound/soc/davinci/davinci-mcasp.c b/sound/soc/davinci/davinci-mcasp.c
index 267aee776b2d..740030b4d37a 100644
--- a/sound/soc/davinci/davinci-mcasp.c
+++ b/sound/soc/davinci/davinci-mcasp.c
@@ -192,6 +192,7 @@ static void mcasp_start_rx(struct davinci_mcasp *mcasp)
}
/* Activate serializer(s) */
+ mcasp_set_reg(mcasp, DAVINCI_MCASP_RXSTAT_REG, 0xFFFFFFFF);
mcasp_set_ctl_reg(mcasp, DAVINCI_MCASP_GBLCTLR_REG, RXSERCLR);
/* Release RX state machine */
mcasp_set_ctl_reg(mcasp, DAVINCI_MCASP_GBLCTLR_REG, RXSMRST);
@@ -220,6 +221,7 @@ static void mcasp_start_tx(struct davinci_mcasp *mcasp)
mcasp_set_ctl_reg(mcasp, DAVINCI_MCASP_GBLCTLX_REG, TXHCLKRST);
mcasp_set_ctl_reg(mcasp, DAVINCI_MCASP_GBLCTLX_REG, TXCLKRST);
/* Activate serializer(s) */
+ mcasp_set_reg(mcasp, DAVINCI_MCASP_TXSTAT_REG, 0xFFFFFFFF);
mcasp_set_ctl_reg(mcasp, DAVINCI_MCASP_GBLCTLX_REG, TXSERCLR);
/* wait for XDATA to be cleared */
--
2.19.1