Commit 7c289385 authored by Russell King's avatar Russell King
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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: default avatarRussell King <>
parent ec11594f
......@@ -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);
......@@ -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);
writel(aaci->maincr, aaci->base + AACI_MAINCR);
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