Re: [PATCH 1/2] ALSA: tea6330t: add mixer state restore helper

[Takashi Iwai <tiwai@suse.de>]

On Tue, 07 Apr 2026 03:22:07 +0200,
Cássio Gabriel wrote:
> diff --git a/sound/i2c/tea6330t.c b/sound/i2c/tea6330t.c
> index e8c50a036bea..3e413929d3ea 100644
> --- a/sound/i2c/tea6330t.c
> +++ b/sound/i2c/tea6330t.c
> @@ -358,3 +358,36 @@ int snd_tea6330t_update_mixer(struct snd_card *card,
>  
>  EXPORT_SYMBOL(snd_tea6330t_detect);
>  EXPORT_SYMBOL(snd_tea6330t_update_mixer);

Oh we need a cleanup to put EXPORT_SYMBOL() after each function.
(It should be a different patch, though.)

> +
> +int snd_tea6330t_restore_mixer(struct snd_i2c_bus *bus)
> +{
> +	struct snd_i2c_device *device;
> +	struct tea6330t *tea;
> +	unsigned char bytes[7];
> +	unsigned int idx;
> +	int err;
> +
> +	if (!bus)
> +		return -EINVAL;
> +
> +	list_for_each_entry(device, &bus->devices, list) {
> +		if (device->addr != TEA6330T_ADDR)
> +			continue;
> +
> +		tea = device->private_data;
> +		if (!tea)
> +			return -EINVAL;
> +
> +		snd_i2c_lock(bus);
> +		bytes[0] = TEA6330T_SADDR_VOLUME_LEFT;
> +		for (idx = 0; idx < 6; idx++)
> +			bytes[idx + 1] = tea->regs[idx];
> +		err = snd_i2c_sendbytes(device, bytes, 7);
> +		snd_i2c_unlock(bus);
> +
> +		return err < 0 ? err : 0;
> +	}

I think snd_i2c_lock() should cover the whole loop for the race at
linked list traversal.


thanks,

Takashi