From mboxrd@z Thu Jan  1 00:00:00 1970
From: lee.jones@linaro.org (Lee Jones)
Date: Mon, 29 Sep 2014 08:53:32 +0100
Subject: mfd_add_devices() doesn't check whether nodes are "diabled" in dts
In-Reply-To: <CAGsJ_4yqumj3=54HwxuzVffPjHdQZrCP2wYc2TSumKsg0-wm7w@mail.gmail.com>
References: <CAGsJ_4yqumj3=54HwxuzVffPjHdQZrCP2wYc2TSumKsg0-wm7w@mail.gmail.com>
Message-ID: <20140929075332.GC7308@lee--X1>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On Mon, 29 Sep 2014, Barry Song wrote:

> hi Samuel, Lee,
> the current mfd_add_devices() doesn't check whether nodes are diabled
> in dts, so even though we put status = "disabled" in dts for a MFD
> subnode, it will still create the platform_device. this will cause the
> platform_driver to execute probe() entry.
> 
> mfd-core is doing:
> 
> mfd_add_device()
> 
> alloc platform_device no matter it is disabled or not:
> 
> 92         pdev = platform_device_alloc(cell->name, id + cell->id);
>  93         if (!pdev)
>  94                 goto fail_alloc;
> 
> ....
> extend all nodes:
> 
> 112         if (parent->of_node && cell->of_compatible) {
> 113                 for_each_child_of_node(parent->of_node, np) {
> 114                         if (of_device_is_compatible(np,
> cell->of_compatible)) {
> 115                                 pdev->dev.of_node = np;
> 116                                 break;
> 117                         }
> 118                 }
> 119         }
> 
> it seems it doesn't match with the general behavior like
> of_platform_populate(), in which we only extend available nodes.
> 
> how do you think if we do a fix for the behaviour of mfd_add_devices()
> and mfd_remove_devices()?

Yes, sounds good.

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org ? Open source software for ARM SoCs
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