Subject: Re: [PATCH v2 1/8] i2c-mux: add common core data for every mux
 instance
To: Peter Rosin <peda@lysator.liu.se>
References: <1452009438-27347-1-git-send-email-peda@lysator.liu.se>
 <1452009438-27347-2-git-send-email-peda@lysator.liu.se>
CC: Wolfram Sang <wsa@the-dreams.de>, Peter Rosin <peda@axentia.se>,
        Rob Herring <robh+dt@kernel.org>, Pawel Moll <pawel.moll@arm.com>,
        Mark Rutland <mark.rutland@arm.com>,
        Ian Campbell <ijc+devicetree@hellion.org.uk>,
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From: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Message-ID: <56F3B86E.4050002@mentor.com>
Date: Thu, 24 Mar 2016 11:50:38 +0200
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Hi Peter,

On 05.01.2016 17:57, Peter Rosin wrote:
> From: Peter Rosin <peda@axentia.se>
> 
> The initial core mux structure starts off small with only the parent
> adapter pointer, which all muxes have, and a priv pointer for mux
> driver private data.
> 
> Add i2c_mux_alloc function to unify the creation of a mux.
> 
> Where appropriate, pass around the mux core structure instead of the
> parent adapter or the driver private data.
> 
> Remove the parent adapter pointer from the driver private data for all
> mux drivers.
> 
> Signed-off-by: Peter Rosin <peda@axentia.se>

is it still under review? If yes, please find one question from me below :)

[snip]

> @@ -196,21 +195,21 @@ static int i2c_arbitrator_probe(struct platform_device *pdev)
>  		dev_err(dev, "Cannot parse i2c-parent\n");
>  		return -EINVAL;
>  	}
> -	arb->parent = of_get_i2c_adapter_by_node(parent_np);
> +	muxc->parent = of_find_i2c_adapter_by_node(parent_np);

why do you prefer here to use "unlocked" version of API?

Foe example would it be safe/possible to unload an I2C bus device driver
module or unbind I2C device itself in runtime?

>  	of_node_put(parent_np);
> -	if (!arb->parent) {
> +	if (!muxc->parent) {
>  		dev_err(dev, "Cannot find parent bus\n");
>  		return -EPROBE_DEFER;
>  	}
>  
>  	/* Actually add the mux adapter */
> -	arb->child = i2c_add_mux_adapter(arb->parent, dev, arb, 0, 0, 0,
> +	arb->child = i2c_add_mux_adapter(muxc, dev, arb, 0, 0, 0,
>  					 i2c_arbitrator_select,
>  					 i2c_arbitrator_deselect);
>  	if (!arb->child) {
>  		dev_err(dev, "Failed to add adapter\n");
>  		ret = -ENODEV;
> -		i2c_put_adapter(arb->parent);
> +		i2c_put_adapter(muxc->parent);
>  	}
>  
>  	return ret;

--
With best wishes,
Vladimir