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  • Rafael J. Wysocki's avatar
    ACPI / platform: Initialize ACPI handles of platform devices in advance · 863f9f30
    Rafael J. Wysocki authored
    
    
    The current platform device creation and registration code in
    acpi_create_platform_device() is quite convoluted.  This function
    takes an ACPI device node as an argument and eventually calls
    platform_device_register_resndata() to create and register a
    platform device object on the basis of the information contained
    in that code.  However, it doesn't associate the new platform
    device with the ACPI node directly, but instead it relies on
    acpi_platform_notify(), called from within device_add(), to find
    that ACPI node again with the help of acpi_platform_find_device()
    and acpi_platform_match() and then attach the new platform device
    to it.  This causes an additional ACPI namespace walk to happen and
    is clearly suboptimal.
    
    Use the observation that it is now possible to initialize the ACPI
    handle of a device before calling device_add() for it to make this
    code more straightforward.  Namely, add a new field to struct
    platform_device_info allowing us to pass the ACPI handle of interest
    to platform_device_register_full(), which will then use it to
    initialize the new device's ACPI handle before registering it.
    This will cause acpi_platform_notify() to use the ACPI handle from
    the device structure directly instead of using the .find_device()
    routine provided by the device's bus type.  In consequence,
    acpi_platform_bus, acpi_platform_find_device(), and
    acpi_platform_match() are not necessary any more, so remove them.
    
    Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
    Reviewed-by: default avatarMika Westerberg <mika.westerberg@linux.intel.com>
    Acked-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
    863f9f30