Re: [PATCH] ALSA: at73c213: manage SSC clock

From: Måns Rullgård
Date: Sun Jan 17 2016 - 09:43:31 EST


Mans Rullgard <mans@xxxxxxxxx> writes:

> Since commit 49af54ff0fc7 ("misc: atmel-ssc: prepare clock only when
> request") the SSC driver expects clients to manage the SSC clock.
> Update this driver accordingly.
>
> Signed-off-by: Mans Rullgard <mans@xxxxxxxxx>
> ---
> sound/spi/at73c213.c | 8 ++++++++
> 1 file changed, 8 insertions(+)

On second thoughts, please disregard this patch. It's better to enable
the clock only when it is actually required.

> diff --git a/sound/spi/at73c213.c b/sound/spi/at73c213.c
> index 39522367897c..3b2d0b2be421 100644
> --- a/sound/spi/at73c213.c
> +++ b/sound/spi/at73c213.c
> @@ -981,6 +981,8 @@ static int snd_at73c213_probe(struct spi_device *spi)
> goto out_card;
> }
>
> + clk_enable(chip->ssc->clk);
> +
> retval = snd_at73c213_dev_init(card, spi);
> if (retval)
> goto out_ssc;
> @@ -998,6 +1000,7 @@ static int snd_at73c213_probe(struct spi_device *spi)
> goto out;
>
> out_ssc:
> + clk_disable(chip->ssc->clk);
> ssc_free(chip->ssc);
> out_card:
> snd_card_free(card);
> @@ -1066,6 +1069,9 @@ out:
> /* Stop DAC master clock. */
> clk_disable(chip->board->dac_clk);
>
> + /* Stop SSC clock. */
> + clk_disable(chip->ssc->clk);
> +
> ssc_free(chip->ssc);
> snd_card_free(card);
>
> @@ -1080,6 +1086,7 @@ static int snd_at73c213_suspend(struct device *dev)
> struct snd_at73c213 *chip = card->private_data;
>
> ssc_writel(chip->ssc->regs, CR, SSC_BIT(CR_TXDIS));
> + clk_disable(chip->ssc->clk);
> clk_disable(chip->board->dac_clk);
>
> return 0;
> @@ -1091,6 +1098,7 @@ static int snd_at73c213_resume(struct device *dev)
> struct snd_at73c213 *chip = card->private_data;
>
> clk_enable(chip->board->dac_clk);
> + clk_enable(chip->ssc->clk);
> ssc_writel(chip->ssc->regs, CR, SSC_BIT(CR_TXEN));
>
> return 0;
> --
> 2.7.0
>

--
Måns Rullgård