From b243b77c708665d7af8c5e42611c27c89f918788 Mon Sep 17 00:00:00 2001 From: Karl Beldan Date: Thu, 14 May 2009 10:25:42 +0200 Subject: [PATCH] ASoC: pxa2xx-i2s: Proper hw initialization Make sure we are in a know good state at end of probe : Reset FIFO logic and registers, and make sure REC and RPL functions along with FIFO service are disabled (SACR0_RST enables REC and RPL). Resetting loses current settings so remove reset from stream startup. Now reset occurs only at probe. Signed-off-by: Karl Beldan Signed-off-by: Mark Brown --- sound/soc/pxa/pxa2xx-i2s.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) diff --git a/sound/soc/pxa/pxa2xx-i2s.c b/sound/soc/pxa/pxa2xx-i2s.c index 6014577..bb8630b 100644 --- a/sound/soc/pxa/pxa2xx-i2s.c +++ b/sound/soc/pxa/pxa2xx-i2s.c @@ -106,10 +106,8 @@ static int pxa2xx_i2s_startup(struct snd_pcm_substream *substream, if (IS_ERR(clk_i2s)) return PTR_ERR(clk_i2s); - if (!cpu_dai->active) { - SACR0 |= SACR0_RST; + if (!cpu_dai->active) SACR0 = 0; - } return 0; } @@ -347,6 +345,19 @@ static int pxa2xx_i2s_probe(struct platform_device *dev) if (ret != 0) clk_put(clk_i2s); + /* + * PXA Developer's Manual: + * If SACR0[ENB] is toggled in the middle of a normal operation, + * the SACR0[RST] bit must also be set and cleared to reset all + * I2S controller registers. + */ + SACR0 = SACR0_RST; + SACR0 = 0; + /* Make sure RPL and REC are disabled */ + SACR1 = SACR1_DRPL | SACR1_DREC; + /* Along with FIFO servicing */ + SAIMR &= ~(SAIMR_RFS | SAIMR_TFS); + return ret; } -- 2.7.4