This patch will take care not to overwrite OCA and ICA registers when assigning input and output channels. It will also make sure the registers are at a known state when enabling a channel and clean up properly in case of an error.
Signed-off-by: Hans-Christian Egtvedt hans-christian.egtvedt@atmel.com --- sound/atmel/ac97c.c | 23 ++++++++++++++++++----- 1 files changed, 18 insertions(+), 5 deletions(-)
diff --git a/sound/atmel/ac97c.c b/sound/atmel/ac97c.c index 21be9c9..4e8f66d 100644 --- a/sound/atmel/ac97c.c +++ b/sound/atmel/ac97c.c @@ -1,5 +1,5 @@ /* - * Driver for the Atmel AC97C controller + * Driver for Atmel AC97C * * Copyright (C) 2005-2009 Atmel Corporation * @@ -10,6 +10,7 @@ #include <linux/clk.h> #include <linux/delay.h> #include <linux/bitmap.h> +#include <linux/device.h> #include <linux/dmaengine.h> #include <linux/dma-mapping.h> #include <linux/init.h> @@ -297,9 +298,11 @@ static int atmel_ac97c_playback_prepare(struct snd_pcm_substream *substream) { struct atmel_ac97c *chip = snd_pcm_substream_chip(substream); struct snd_pcm_runtime *runtime = substream->runtime; - unsigned long word = 0; + unsigned long word = ac97c_readl(chip, OCA); int retval;
+ word &= ~(AC97C_CH_MASK(PCM_LEFT) | AC97C_CH_MASK(PCM_RIGHT)); + /* assign channels to AC97C channel A */ switch (runtime->channels) { case 1: @@ -323,9 +326,13 @@ static int atmel_ac97c_playback_prepare(struct snd_pcm_substream *substream) word |= AC97C_CMR_CEM_LITTLE; break; case SNDRV_PCM_FORMAT_S16_BE: /* fall through */ - default: word &= ~(AC97C_CMR_CEM_LITTLE); break; + default: + word = ac97c_readl(chip, OCA); + word &= ~(AC97C_CH_MASK(PCM_LEFT) | AC97C_CH_MASK(PCM_RIGHT)); + ac97c_writel(chip, OCA, word); + return -EINVAL; }
ac97c_writel(chip, CAMR, word); @@ -358,9 +365,11 @@ static int atmel_ac97c_capture_prepare(struct snd_pcm_substream *substream) { struct atmel_ac97c *chip = snd_pcm_substream_chip(substream); struct snd_pcm_runtime *runtime = substream->runtime; - unsigned long word = 0; + unsigned long word = ac97c_readl(chip, ICA); int retval;
+ word &= ~(AC97C_CH_MASK(PCM_LEFT) | AC97C_CH_MASK(PCM_RIGHT)); + /* assign channels to AC97C channel A */ switch (runtime->channels) { case 1: @@ -384,9 +393,13 @@ static int atmel_ac97c_capture_prepare(struct snd_pcm_substream *substream) word |= AC97C_CMR_CEM_LITTLE; break; case SNDRV_PCM_FORMAT_S16_BE: /* fall through */ - default: word &= ~(AC97C_CMR_CEM_LITTLE); break; + default: + word = ac97c_readl(chip, ICA); + word &= ~(AC97C_CH_MASK(PCM_LEFT) | AC97C_CH_MASK(PCM_RIGHT)); + ac97c_writel(chip, ICA, word); + return -EINVAL; }
ac97c_writel(chip, CAMR, word);