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Date:   Mon, 11 Jan 2021 15:42:27 -0800 (PST)
From:   Hugh Dickins <hughd@google.com>
To:     Saravana Kannan <saravanak@google.com>
cc:     "Rafael J. Wysocki" <rafael@kernel.org>,
        Thierry Reding <treding@nvidia.com>,
        Hugh Dickins <hughd@google.com>,
        Jonathan Hunter <jonathanh@nvidia.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Vincent Huang <vincent.huang@tw.synaptics.com>,
        "Jason A. Donenfeld" <Jason@zx2c4.com>,
        Andrew Duggan <aduggan@synaptics.com>,
        Lucas Stach <l.stach@pengutronix.de>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Linux PM <linux-pm@vger.kernel.org>
Subject: Re: 5.11-rc device reordering breaks ThinkPad rmi4 suspend
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On Mon, 11 Jan 2021, Saravana Kannan wrote:
> 
> I happen to have an X1 Carbon (different gen though) lying around and
> I poked at its /sys folders. None of the devices in the rmi4_smbus are
> considered the grandchildren of the i2c device. I think the real
> problem is rmi_register_transport_device() [1] not setting up the
> parent for any of the new devices it's adding.
> 
> Hugh, can you try this patch?

Just tried, but no, this patch does not help; but I bet
you're along the right lines, and something as simple will do it.

> 
> diff --git a/drivers/input/rmi4/rmi_bus.c b/drivers/input/rmi4/rmi_bus.c
> index 24f31a5c0e04..50a0134b6901 100644
> --- a/drivers/input/rmi4/rmi_bus.c
> +++ b/drivers/input/rmi4/rmi_bus.c
> @@ -90,6 +90,7 @@ int rmi_register_transport_device(struct
> rmi_transport_dev *xport)
> 
>         rmi_dev->dev.bus = &rmi_bus_type;
>         rmi_dev->dev.type = &rmi_device_type;
> +       rmi_dev->dev.parent = xport->dev;
> 
>         xport->rmi_dev = rmi_dev;
> 
> -Saravana
> 
> [1] - https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/input/rmi4/rmi_bus.c#n74