[PATCH v2 2/3] ASoC: sh: fsi: Fix clock inversion

[Geert Uytterhoeven]

On Wed, Jan 21, 2015 at 2:38 PM, Lars-Peter Clausen <lars at metafoo.de> 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-justfied mode both the frame-clock and the
> bit-clock need to be inverted to be standards compliant.
>
> This means also that the exta 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>
> ---
> I don't have the hardware but I'd like to get rid of the extra
> SND_SOC_DAIFMT_IB_NF in simple-card platform data, so we can remove the fmt
> field. Kuninori can you check if this works?
>
> Changes since v1:
>         * Fix whitespace
> ---
>  arch/arm/mach-shmobile/board-armadillo800eva.c | 1 -

The board files are gone by now.

>  sound/soc/sh/fsi.c                             | 7 +++++++

Is this part still applicable?

>  2 files changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/arch/arm/mach-shmobile/board-armadillo800eva.c b/arch/arm/mach-shmobile/board-armadillo800eva.c
> index 75de26c..36aaeb1 100644
> --- a/arch/arm/mach-shmobile/board-armadillo800eva.c
> +++ b/arch/arm/mach-shmobile/board-armadillo800eva.c
> @@ -1015,7 +1015,6 @@ static struct asoc_simple_card_info fsi_wm8978_info = {
>         .platform       = "sh_fsi2",
>         .daifmt         = SND_SOC_DAIFMT_I2S | SND_SOC_DAIFMT_CBM_CFM,
>         .cpu_dai = {
> -               .fmt    = SND_SOC_DAIFMT_IB_NF,
>                 .name   = "fsia-dai",
>         },
>         .codec_dai = {
> diff --git a/sound/soc/sh/fsi.c b/sound/soc/sh/fsi.c
> index b87b22e..6783d3f 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;
> +
>         switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
>         case SND_SOC_DAIFMT_I2S:
>                 fsi->fmt = CR_I2S;
> @@ -1602,6 +1608,7 @@ static int fsi_set_fmt_dai(struct fsi_priv *fsi, unsigned int fmt)
>         case SND_SOC_DAIFMT_LEFT_J:
>                 fsi->fmt = CR_PCM;
>                 fsi->chan_num = 2;
> +               fsi->lr_clk_inv = !fsi->lr_clk_inv;
>                 break;
>         default:
>                 return -EINVAL;
> --
> 1.8.0

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds