diff options
| author | Russell King <rmk+kernel@arm.linux.org.uk> | 2011-02-05 10:41:55 +0000 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2011-02-07 15:15:26 +0000 |
| commit | 7c289385b84d136089b8a1149321ebffa5193595 (patch) | |
| tree | 2d591872a86dfa7f042371501d014e54e3ecda50 | |
| parent | ec11594fbd5a3d2a47a7a7eda6d076363b78957c (diff) | |
ALSA: AACI: allow writes to MAINCR to take effect
The AACI TRM requires the MAINCR enable bit to be held zero for two
bitclk cycles plus three apb_pclk cycles. Use a delay of 1us to
ensure this.
Ensure that writes to MAINCR to change the addressed codec only happen
when required, and that they take effect in a similar manner to the
above, otherwise we seem to occasionally have stuck slot busy bits.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
| -rw-r--r-- | sound/arm/aaci.c | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/sound/arm/aaci.c b/sound/arm/aaci.c index 24d3013c023..7c1fc64cb53 100644 --- a/sound/arm/aaci.c +++ b/sound/arm/aaci.c @@ -50,7 +50,11 @@ static void aaci_ac97_select_codec(struct aaci *aaci, struct snd_ac97 *ac97) if (v & SLFR_1RXV) readl(aaci->base + AACI_SL1RX); - writel(maincr, aaci->base + AACI_MAINCR); + if (maincr != readl(aaci->base + AACI_MAINCR)) { + writel(maincr, aaci->base + AACI_MAINCR); + readl(aaci->base + AACI_MAINCR); + udelay(1); + } } /* @@ -993,6 +997,8 @@ static unsigned int __devinit aaci_size_fifo(struct aaci *aaci) * disabling the channel doesn't clear the FIFO. */ writel(aaci->maincr & ~MAINCR_IE, aaci->base + AACI_MAINCR); + readl(aaci->base + AACI_MAINCR); + udelay(1); writel(aaci->maincr, aaci->base + AACI_MAINCR); /* |