drm: Provide PCI module-init macros

kernel log at initialization time and passes it to userspace through the

DRM_IOCTL_VERSION ioctl.

Module Initialization

---------------------

.. kernel-doc:: include/drm/drm_module.h

   :doc: overview

Managing Ownership of the Framebuffer Aperture

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/* SPDX-License-Identifier: MIT */

#ifndef DRM_MODULE_H

#define DRM_MODULE_H

#include <linux/pci.h>

#include <drm/drm_drv.h>

/**

 * DOC: overview

 *

 * This library provides helpers registering DRM drivers during module

 * initialization and shutdown. The provided helpers act like bus-specific

 * module helpers, such as module_pci_driver(), but respect additional

 * parameters that control DRM driver registration.

 *

 * Below is an example of initializing a DRM driver for a device on the

 * PCI bus.

 *

 * .. code-block:: c

 *

 *	struct pci_driver my_pci_drv = {

 *	};

 *

 *	drm_module_pci_driver(my_pci_drv);

 *

 * The generated code will test if DRM drivers are enabled and register

 * the PCI driver my_pci_drv. For more complex module initialization, you

 * can still use module_init() and module_exit() in your driver.

 */

/*

 * PCI drivers

 */

static inline int __init drm_pci_register_driver(struct pci_driver *pci_drv)

{

	if (drm_firmware_drivers_only())

		return -ENODEV;

	return pci_register_driver(pci_drv);

}

/**

 * drm_module_pci_driver - Register a DRM driver for PCI-based devices

 * @__pci_drv: the PCI driver structure

 *

 * Registers a DRM driver for devices on the PCI bus. The helper

 * macro behaves like module_pci_driver() but tests the state of

 * drm_firmware_drivers_only(). For more complex module initialization,

 * use module_init() and module_exit() directly.

 *

 * Each module may only use this macro once. Calling it replaces

 * module_init() and module_exit().

 */

#define drm_module_pci_driver(__pci_drv) \

	module_driver(__pci_drv, drm_pci_register_driver, pci_unregister_driver)

static inline int __init

drm_pci_register_driver_if_modeset(struct pci_driver *pci_drv, int modeset)

{

	if (drm_firmware_drivers_only() && modeset == -1)

		return -ENODEV;

	if (modeset == 0)

		return -ENODEV;

	return pci_register_driver(pci_drv);

}

static inline void __exit

drm_pci_unregister_driver_if_modeset(struct pci_driver *pci_drv, int modeset)

{

	pci_unregister_driver(pci_drv);

}

/**

 * drm_module_pci_driver_if_modeset - Register a DRM driver for PCI-based devices

 * @__pci_drv: the PCI driver structure

 * @__modeset: an additional parameter that disables the driver

 *

 * This macro is deprecated and only provided for existing drivers. For

 * new drivers, use drm_module_pci_driver().

 *

 * Registers a DRM driver for devices on the PCI bus. The helper macro

 * behaves like drm_module_pci_driver() with an additional driver-specific

 * flag. If __modeset is 0, the driver has been disabled, if __modeset is

 * -1 the driver state depends on the global DRM state. For all other

 * values, the PCI driver has been enabled. The default should be -1.

 */

#define drm_module_pci_driver_if_modeset(__pci_drv, __modeset) \

	module_driver(__pci_drv, drm_pci_register_driver_if_modeset, \

		      drm_pci_unregister_driver_if_modeset, __modeset)

#endif