linux-kernel - Re: [PATCHv1 15/19] power: supply: sbs-battery: add ability to disable charger broadcasts

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Date:   Fri, 15 May 2020 15:57:55 +0100
From:   Emil Velikov <emil.velikov@...labora.com>
To:     Sebastian Reichel <sebastian.reichel@...labora.com>
Cc:     Sebastian Reichel <sre@...nel.org>,
        Rob Herring <robh+dt@...nel.org>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        "Rafael J . Wysocki" <rafael@...nel.org>, linux-pm@...r.kernel.org,
        devicetree@...r.kernel.org, linux-kernel@...r.kernel.org,
        kernel@...labora.com,
        Jean-Francois Dagenais <jeff.dagenais@...il.com>
Subject: Re: [PATCHv1 15/19] power: supply: sbs-battery: add ability to
 disable charger broadcasts

On 2020/05/13, Sebastian Reichel wrote:
> From: Jean-Francois Dagenais <jeff.dagenais@...il.com>
> 
> In certain designs, it is possible to add a battery on a populated i2c
> bus without an sbs compliant charger. In that case, the battery will
> un-necessarily and sometimes un-desirably master the bus trying to write
> info in the charger.

Nit: s/un-/un/

> 
> It is observed in many occasion that these battery "broadcasts" are even
> corrupting other ongoing master to slave communication. I.e. the
> multi-master support in the battery is inadequate.
> 
> Thankfully, the CHARGER_MODE bit allows designers to disable that SBS
> battery behaviour.
> 
> This needs to be done once when the battery is first seen on the bus.
> 
> Signed-off-by: Jean-Francois Dagenais <jeff.dagenais@...il.com>
> [rebased code]
> Signed-off-by: Sebastian Reichel <sebastian.reichel@...labora.com>
> ---

> @@ -1017,6 +1043,9 @@ static int sbs_probe(struct i2c_client *client,
>  	}
>  	chip->i2c_retry_count = chip->i2c_retry_count + 1;
>  
> +	chip->charger_broadcasts = !of_property_read_bool(client->dev.of_node,
> +					"sbs,disable-charger-broadcasts");
> +
This patch adds the of_property_read, only for it to be replaced in the next
patch. Consider flipping the patch order?

-Emil