[PATCH 1/3] ASoC: core: Add common helper to parse aux devs from device tree

[Jerome Brunet]

On Sat 01 Aug 2020 at 12:02, Stephan Gerhold <stephan at gerhold.net> wrote:

> simple-card.c and meson-card-utils.c use pretty much the same
> helper function to parse auxiliary devices from the device tree.
>
> Make it easier for other drivers to parse these from the device tree
> as well by adding a shared helper function to soc-core.c.
>
> snd_soc_of_parse_aux_devs() is pretty much a copy of
> meson_card_add_aux_devices() from meson-card-utils.c
> with two minor changes:
>
>   - Make property name configurable as parameter
>   - Change dev_err() message slightly for consistency with other
>     error messages in soc-core.c
>
> Signed-off-by: Stephan Gerhold <stephan at gerhold.net>

When you send multiple patches like that, you should a cover-letter
describing the overall purpose of the patchset, then the patches

If you look around on the mailing list this cover is usually starting
with the subject "[PATCH 0/X]"

Apart from this, the change looks good to me

Reviewed-by: Jerome Brunet <jbrunet at baylibre.com>

> ---
> I have another patch set that I will submit separately which makes
> use of this function to parse aux devs from the device tree within
> qcom_snd_parse_of(). This is preparation for that patch set.
> ---
>  include/sound/soc.h  |  1 +
>  sound/soc/soc-core.c | 31 +++++++++++++++++++++++++++++++
>  2 files changed, 32 insertions(+)
>
> diff --git a/include/sound/soc.h b/include/sound/soc.h
> index 5e3919ffb00c..a0918d159fd3 100644
> --- a/include/sound/soc.h
> +++ b/include/sound/soc.h
> @@ -1331,6 +1331,7 @@ void snd_soc_of_parse_audio_prefix(struct snd_soc_card *card,
>  
>  int snd_soc_of_parse_audio_routing(struct snd_soc_card *card,
>  				   const char *propname);
> +int snd_soc_of_parse_aux_devs(struct snd_soc_card *card, const char *propname);
>  unsigned int snd_soc_of_parse_daifmt(struct device_node *np,
>  				     const char *prefix,
>  				     struct device_node **bitclkmaster,
> diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c
> index 2fe1b2ec7c8f..bf46f410c8c6 100644
> --- a/sound/soc/soc-core.c
> +++ b/sound/soc/soc-core.c
> @@ -2827,6 +2827,37 @@ int snd_soc_of_parse_audio_routing(struct snd_soc_card *card,
>  }
>  EXPORT_SYMBOL_GPL(snd_soc_of_parse_audio_routing);
>  
> +int snd_soc_of_parse_aux_devs(struct snd_soc_card *card, const char *propname)
> +{
> +	struct device_node *node = card->dev->of_node;
> +	struct snd_soc_aux_dev *aux;
> +	int num, i;
> +
> +	num = of_count_phandle_with_args(node, propname, NULL);
> +	if (num == -ENOENT) {
> +		return 0;
> +	} else if (num < 0) {
> +		dev_err(card->dev, "ASOC: Property '%s' could not be read: %d\n",
> +			propname, num);
> +		return num;
> +	}
> +
> +	aux = devm_kcalloc(card->dev, num, sizeof(*aux), GFP_KERNEL);
> +	if (!aux)
> +		return -ENOMEM;
> +	card->aux_dev = aux;
> +	card->num_aux_devs = num;
> +
> +	for_each_card_pre_auxs(card, i, aux) {
> +		aux->dlc.of_node = of_parse_phandle(node, propname, i);
> +		if (!aux->dlc.of_node)
> +			return -EINVAL;
> +	}
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL_GPL(snd_soc_of_parse_aux_devs);
> +
>  unsigned int snd_soc_of_parse_daifmt(struct device_node *np,
>  				     const char *prefix,
>  				     struct device_node **bitclkmaster,