Accessing a pdev or its members
greg at kroah.com
Sat Sep 25 02:31:33 EDT 2021
On Fri, Sep 24, 2021 at 09:30:55PM -0500, Drew Abbott wrote:
> Hello all,
> A third party driver has a probe function foo_probe(struct
> platform_device) that ends up allocating and initializing a list of
> various device structs:
> struct device *dev = &pdev->dev;
> struct ucsi_dev *udev;
> udev = devm_kzalloc(dev, sizeof(*udev), GFP_KERNEL);
> /* initialize udev to important data */
> platform_set_drvdata(pdev, udev);
> I have my own driver that I would like to use to access the *udev that
> is created when the other device is probed. How would I access a pdev?
You can not, it is not owned by your driver and the lifetime rules
should not give you access to it.
Why would you want to poke around in a platform device that is
controlled by a different driver? What does your driver want to do?
> Or is there a way I can add a function to this driver to expose a
> *udev? I can't seem to get to it without having a pointer to the pdev,
> the udev, or some other device struct related to the hardware.
Why not move your functionality into the existing driver if you need to
talk to the same hardware device?
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