ASoC: don't touch pxa-ssp registers when stream is running
In pxa_ssp_set_dai_fmt(), check whether there is anything to do at all.
If there would be but the SSP port is in use already, bail out.
Signed-off-by: Daniel Mack <daniel@caiaq.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/sound/soc/pxa/pxa-ssp.c b/sound/soc/pxa/pxa-ssp.c
index 7fc13f0..52d97c4 100644
--- a/sound/soc/pxa/pxa-ssp.c
+++ b/sound/soc/pxa/pxa-ssp.c
@@ -522,6 +522,17 @@
u32 sscr1;
u32 sspsp;
+ /* check if we need to change anything at all */
+ if (priv->dai_fmt == fmt)
+ return 0;
+
+ /* we can only change the settings if the port is not in use */
+ if (ssp_read_reg(ssp, SSCR0) & SSCR0_SSE) {
+ dev_err(&ssp->pdev->dev,
+ "can't change hardware dai format: stream is in use");
+ return -EINVAL;
+ }
+
/* reset port settings */
sscr0 = ssp_read_reg(ssp, SSCR0) &
(SSCR0_ECS | SSCR0_NCS | SSCR0_MOD | SSCR0_ACS);