Message ID | 1340690623-18177-1-git-send-email-gururaja.hebbar@ti.com (mailing list archive) |
---|---|
State | Awaiting Upstream |
Headers | show |
Hi Gururaja, shouldn't be better to use: snd_soc_update_bits(codec, AIC3X_PLL_PROGA_REG, PLLP_MASK, pll_p); instead of "read mask write" ? Even at this place you don't need to keep rest of register (PLL_Q and PLL_enable), so yust writing is OK. snd_soc_write(codec, AIC3X_PLL_PROGA_REG, pll_p << PLLP_SHIFT); Dne 26.6.2012 08:03, Hebbar, Gururaja napsal(a): > In sound/soc/codecs/tlv320aic3x.c > > data = snd_soc_read(codec, AIC3X_PLL_PROGA_REG); > snd_soc_write(codec, AIC3X_PLL_PROGA_REG, > data | (pll_p<< PLLP_SHIFT)); > > In the above code, pll-p value is OR'ed with previous value without > clearing it. Bug is not seen if pll-p value doesn't change across > Sampling frequency. > > However on some platforms (like AM335x EVM-SK), pll-p may have different > values across different sampling frequencies. In such case, above code > configures the pll with a wrong value. > Because of this bug, when a audio stream is played with pll value > different from previous stream, audio is heard as differently. > > Signed-off-by: Hebbar, Gururaja<gururaja.hebbar@ti.com> > --- > chnages in V2: > modify subject to indicate ASOC and codec as tlv320aic3x > > sound/soc/codecs/tlv320aic3x.c | 2 +- > sound/soc/codecs/tlv320aic3x.h | 1 + > 2 files changed, 2 insertions(+), 1 deletions(-) > > diff --git a/sound/soc/codecs/tlv320aic3x.c b/sound/soc/codecs/tlv320aic3x.c > index d0dbac1..8c1977b 100644 > --- a/sound/soc/codecs/tlv320aic3x.c > +++ b/sound/soc/codecs/tlv320aic3x.c > @@ -963,7 +963,7 @@ static int aic3x_hw_params(struct snd_pcm_substream *substream, > } > > found: > - data = snd_soc_read(codec, AIC3X_PLL_PROGA_REG); > + data = snd_soc_read(codec, AIC3X_PLL_PROGA_REG)& ~PLLP_MASK; > snd_soc_write(codec, AIC3X_PLL_PROGA_REG, > data | (pll_p<< PLLP_SHIFT)); > snd_soc_write(codec, AIC3X_OVRF_STATUS_AND_PLLR_REG, > diff --git a/sound/soc/codecs/tlv320aic3x.h b/sound/soc/codecs/tlv320aic3x.h > index 06a1978..16d9999 100644 > --- a/sound/soc/codecs/tlv320aic3x.h > +++ b/sound/soc/codecs/tlv320aic3x.h > @@ -166,6 +166,7 @@ > > /* PLL registers bitfields */ > #define PLLP_SHIFT 0 > +#define PLLP_MASK 7 > #define PLLQ_SHIFT 3 > #define PLLR_SHIFT 0 > #define PLLJ_SHIFT 2
On Tue, Jun 26, 2012 at 14:24:03, Mark Brown wrote: > On Tue, Jun 26, 2012 at 11:33:43AM +0530, Hebbar, Gururaja wrote: > > In sound/soc/codecs/tlv320aic3x.c > > > > data = snd_soc_read(codec, AIC3X_PLL_PROGA_REG); > > snd_soc_write(codec, AIC3X_PLL_PROGA_REG, > > data | (pll_p << PLLP_SHIFT)); > > > > In the above code, pll-p value is OR'ed with previous value without > > clearing it. Bug is not seen if pll-p value doesn't change across > > Sampling frequency. > > A better fix is to change the code to use snd_soc_update_bits() rather > than open code it. This is more idiomatic and will suppress writes if > they don't change anything. > Sure will resend the patch. Thanks for the review Regards, Gururaja
diff --git a/sound/soc/codecs/tlv320aic3x.c b/sound/soc/codecs/tlv320aic3x.c index d0dbac1..8c1977b 100644 --- a/sound/soc/codecs/tlv320aic3x.c +++ b/sound/soc/codecs/tlv320aic3x.c @@ -963,7 +963,7 @@ static int aic3x_hw_params(struct snd_pcm_substream *substream, } found: - data = snd_soc_read(codec, AIC3X_PLL_PROGA_REG); + data = snd_soc_read(codec, AIC3X_PLL_PROGA_REG) & ~PLLP_MASK; snd_soc_write(codec, AIC3X_PLL_PROGA_REG, data | (pll_p << PLLP_SHIFT)); snd_soc_write(codec, AIC3X_OVRF_STATUS_AND_PLLR_REG, diff --git a/sound/soc/codecs/tlv320aic3x.h b/sound/soc/codecs/tlv320aic3x.h index 06a1978..16d9999 100644 --- a/sound/soc/codecs/tlv320aic3x.h +++ b/sound/soc/codecs/tlv320aic3x.h @@ -166,6 +166,7 @@ /* PLL registers bitfields */ #define PLLP_SHIFT 0 +#define PLLP_MASK 7 #define PLLQ_SHIFT 3 #define PLLR_SHIFT 0 #define PLLJ_SHIFT 2
In sound/soc/codecs/tlv320aic3x.c data = snd_soc_read(codec, AIC3X_PLL_PROGA_REG); snd_soc_write(codec, AIC3X_PLL_PROGA_REG, data | (pll_p << PLLP_SHIFT)); In the above code, pll-p value is OR'ed with previous value without clearing it. Bug is not seen if pll-p value doesn't change across Sampling frequency. However on some platforms (like AM335x EVM-SK), pll-p may have different values across different sampling frequencies. In such case, above code configures the pll with a wrong value. Because of this bug, when a audio stream is played with pll value different from previous stream, audio is heard as differently. Signed-off-by: Hebbar, Gururaja <gururaja.hebbar@ti.com> --- chnages in V2: modify subject to indicate ASOC and codec as tlv320aic3x sound/soc/codecs/tlv320aic3x.c | 2 +- sound/soc/codecs/tlv320aic3x.h | 1 + 2 files changed, 2 insertions(+), 1 deletions(-)