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 <20210722054951.8291-1-ayush.garg@samsung.com> <20210722054951.8291-2-ayush.garg@samsung.com>
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From:   Luiz Augusto von Dentz <luiz.dentz@gmail.com>
Date:   Thu, 22 Jul 2021 10:33:46 -0700
Message-ID: <CABBYNZLZUB1CsJpYqC=ioZrBzM+BV9n6VMPCobFDKsm00FBo4w@mail.gmail.com>
Subject: Re: [PATCH BlueZ 1/8] doc/device-api: Add Phy property
To:     Ayush Garg <ayush.garg@samsung.com>
Cc:     "linux-bluetooth@vger.kernel.org" <linux-bluetooth@vger.kernel.org>,
        Anupam Roy <anupam.r@samsung.com>, nitin.j@samsung.com
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Hi Ayush,

On Wed, Jul 21, 2021 at 11:03 PM Ayush Garg <ayush.garg@samsung.com> wrote:
>
> This will allow to set the LE PHY preferences for
> a connected device.
>
> Reviewed-by: Anupam Roy <anupam.r@samsung.com>
> ---
>  doc/device-api.txt | 22 ++++++++++++++++++++++
>  1 file changed, 22 insertions(+)
>
> diff --git a/doc/device-api.txt b/doc/device-api.txt
> index 4e824d2de..d0e108f74 100644
> --- a/doc/device-api.txt
> +++ b/doc/device-api.txt
> @@ -272,3 +272,25 @@ Properties string Address [readonly]
>                         Example:
>                                 <Transport Discovery> <Organization Flags...>
>                                 0x26                   0x01         0x01...
> +
> +               array{string} Phy [readwrite, optional]
> +
> +                       PHY Preferences for a connected device.
> +
> +                       Note: The controller might not be able to make the
> +                       change because of reasons like peer not supporting
> +                       the requested PHY or it couldnot schedule due to
> +                       other activites.
> +
> +                       This is only available for LE capable controllers.
> +                       It will return Not Supported Otherwise.

The property shall be omitted if LE is not enabled, I guess that was
the intent of optional but saying it would return NotSupport means
otherwise.

> +
> +                       Possible values:
> +                               "LE1MTX"
> +                               "LE1MRX"
> +                               "LE2MTX"
> +                               "LE2MRX"
> +                               "LECODEDTX"
> +                               "LECODEDRX"
> +                               "LECODEDS2"
> +                               "LECODEDS8"
> --
> 2.17.1

I guess the intend here would be to have a prefered PHY for LE, but I
wonder if this would really help since different profiles/service may
have different preferences, also by being an array I assume one would
need to the enter in the preferred order which should probably be
stated and again depending on the use case this could be a config
setting in main.conf instead so it is applied globally to all devices
by drivers can overwrite it with their own preferences.

-- 
Luiz Augusto von Dentz