[PATCH 2/3] ASoC: sh: fsi: Fix clock inversion
Sergei Shtylyov
sergei.shtylyov at cogentembedded.com
Mon Jan 19 04:23:38 PST 2015
Hello.
On 1/19/2015 12:54 PM, Lars-Peter Clausen wrote:
> According to the sh7724 hardware user manual (Rev.2.00 Jan 2013) page 1851
> to 1856 the FSI bit-clock is inverted to the bit-clock as specified by the
> I2S standard. This means the bit clock inversion bit should be set for a
> normal I2S clock and should not be set for an inverted I2S clock.
> Similarly when operating in left-justified mode both the frame-clock and the
> bit-clock need to be inverted to be standards compliant.
> This means also that the extra clock inversion setting in the
> armadillo800eva machine driver for CPU component should now be removed.
> Signed-off-by: Lars-Peter Clausen <lars at metafoo.de>
[...]
> diff --git a/sound/soc/sh/fsi.c b/sound/soc/sh/fsi.c
> index b87b22e..dfb17f6 100644
> --- a/sound/soc/sh/fsi.c
> +++ b/sound/soc/sh/fsi.c
> @@ -1594,6 +1594,12 @@ static int fsi_dai_trigger(struct snd_pcm_substream *substream, int cmd,
>
> static int fsi_set_fmt_dai(struct fsi_priv *fsi, unsigned int fmt)
> {
> + /*
> + * FSI bit clock is inverted to the I2S specification, so we invert it
> + * when a non-inverted I2S clock was requested and vice versa.
> + */
> + fsi->bit_clk_inv = !fsi->bit_clk_inv;
One space too many here. :-)
[...]
WBR, Sergei
More information about the linux-arm-kernel
mailing list