Hi Claudio,

On 04/22/2013 07:58 AM, Claudio Takahasi wrote:
> This patch adds echo canceling and noise reduction property to Handsfree
> interface, allowing the handsfree unit to enable or disable this feature
> in the audio gateway.
>
> According to Bluetooth HFP 1.6 spec: By default, if the AG supports its
> own embedded echo canceling and/or noise reduction functions, it shall
> have them activated until the AT+NREC command is received.
> ---
>   doc/handsfree-api.txt | 7 +++++++
>   1 file changed, 7 insertions(+)
>
> diff --git a/doc/handsfree-api.txt b/doc/handsfree-api.txt
> index 0b5d421..6855d93 100644
> --- a/doc/handsfree-api.txt
> +++ b/doc/handsfree-api.txt
> @@ -56,6 +56,13 @@ Properties	array{string} Features [readonly]
>   			to activate or deactivate the function from the HF, or
>   			the AG could autonomously initiate it.
>
> +		boolean EchoCancelingNoiseReduction [readwrite]
> +
> +			Boolean representing whether echo canceling and noise
> +			reduction is enabled in the AG. This property may be
> +			written to activate or deactivate this feature from
> +			the HF unit.
> +

This feature can only be disabled, not enabled for a given SLC.  So 
setting this to 'True' should return an error or do something way fancier.

I suspect that to implement this properly we need to store the ECNR 
setting on disk (e.g. /var/lib/ofono/<local bdaddr>/<remote 
bdaddr>/handsfree or something) and manage it appropriately inside the core.

>   		byte BatteryChargeLevel [readonly]
>
>   			The current charge level of the battery.  The value

Regards,
-Denis