ASoC: davinci-mcasp: Clear TXSTAT register before activating serializers

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@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/sound/soc/davinci/davinci-mcasp.c b/sound/soc/davinci/davinci-mcasp.c
index 267aee7..740030b 100644 (file)
--- 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 */