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Diffstat (limited to 'Documentation/gpu/drm-internals.rst')
| -rw-r--r-- | Documentation/gpu/drm-internals.rst | 113 |
1 files changed, 7 insertions, 106 deletions
diff --git a/Documentation/gpu/drm-internals.rst b/Documentation/gpu/drm-internals.rst index e35920db1f4c..babfb6143bd9 100644 --- a/Documentation/gpu/drm-internals.rst +++ b/Documentation/gpu/drm-internals.rst @@ -140,12 +140,12 @@ Device Instance and Driver Handling .. kernel-doc:: drivers/gpu/drm/drm_drv.c :doc: driver instance overview -.. kernel-doc:: drivers/gpu/drm/drm_drv.c - :export: - .. kernel-doc:: include/drm/drm_drv.h :internal: +.. kernel-doc:: drivers/gpu/drm/drm_drv.c + :export: + Driver Load ----------- @@ -240,120 +240,21 @@ drivers. .. kernel-doc:: drivers/gpu/drm/drm_pci.c :export: -.. kernel-doc:: drivers/gpu/drm/drm_platform.c - :export: - Open/Close, File Operations and IOCTLs ====================================== -Open and Close --------------- - -Open and close handlers. None of those methods are mandatory:: - - int (*firstopen) (struct drm_device *); - void (*lastclose) (struct drm_device *); - int (*open) (struct drm_device *, struct drm_file *); - void (*preclose) (struct drm_device *, struct drm_file *); - void (*postclose) (struct drm_device *, struct drm_file *); - -The firstopen method is called by the DRM core for legacy UMS (User Mode -Setting) drivers only when an application opens a device that has no -other opened file handle. UMS drivers can implement it to acquire device -resources. KMS drivers can't use the method and must acquire resources -in the load method instead. - -Similarly the lastclose method is called when the last application -holding a file handle opened on the device closes it, for both UMS and -KMS drivers. Additionally, the method is also called at module unload -time or, for hot-pluggable devices, when the device is unplugged. The -firstopen and lastclose calls can thus be unbalanced. - -The open method is called every time the device is opened by an -application. Drivers can allocate per-file private data in this method -and store them in the struct :c:type:`struct drm_file -<drm_file>` driver_priv field. Note that the open method is -called before firstopen. - -The close operation is split into preclose and postclose methods. -Drivers must stop and cleanup all per-file operations in the preclose -method. For instance pending vertical blanking and page flip events must -be cancelled. No per-file operation is allowed on the file handle after -returning from the preclose method. - -Finally the postclose method is called as the last step of the close -operation, right before calling the lastclose method if no other open -file handle exists for the device. Drivers that have allocated per-file -private data in the open method should free it here. - -The lastclose method should restore CRTC and plane properties to default -value, so that a subsequent open of the device will not inherit state -from the previous user. It can also be used to execute delayed power -switching state changes, e.g. in conjunction with the :ref:`vga_switcheroo` -infrastructure. Beyond that KMS drivers should not do any -further cleanup. Only legacy UMS drivers might need to clean up device -state so that the vga console or an independent fbdev driver could take -over. - File Operations --------------- -.. kernel-doc:: drivers/gpu/drm/drm_fops.c +.. kernel-doc:: drivers/gpu/drm/drm_file.c :doc: file operations -.. kernel-doc:: drivers/gpu/drm/drm_fops.c - :export: - -IOCTLs ------- - -struct drm_ioctl_desc \*ioctls; int num_ioctls; - Driver-specific ioctls descriptors table. - -Driver-specific ioctls numbers start at DRM_COMMAND_BASE. The ioctls -descriptors table is indexed by the ioctl number offset from the base -value. Drivers can use the DRM_IOCTL_DEF_DRV() macro to initialize -the table entries. - -:: - - DRM_IOCTL_DEF_DRV(ioctl, func, flags) - -``ioctl`` is the ioctl name. Drivers must define the DRM_##ioctl and -DRM_IOCTL_##ioctl macros to the ioctl number offset from -DRM_COMMAND_BASE and the ioctl number respectively. The first macro is -private to the device while the second must be exposed to userspace in a -public header. - -``func`` is a pointer to the ioctl handler function compatible with the -``drm_ioctl_t`` type. - -:: - - typedef int drm_ioctl_t(struct drm_device *dev, void *data, - struct drm_file *file_priv); - -``flags`` is a bitmask combination of the following values. It restricts -how the ioctl is allowed to be called. - -- DRM_AUTH - Only authenticated callers allowed - -- DRM_MASTER - The ioctl can only be called on the master file handle - -- DRM_ROOT_ONLY - Only callers with the SYSADMIN capability allowed - -- DRM_CONTROL_ALLOW - The ioctl can only be called on a control - device - -- DRM_UNLOCKED - The ioctl handler will be called without locking the - DRM global mutex. This is the enforced default for kms drivers (i.e. - using the DRIVER_MODESET flag) and hence shouldn't be used any more - for new drivers. +.. kernel-doc:: include/drm/drm_file.h + :internal: -.. kernel-doc:: drivers/gpu/drm/drm_ioctl.c +.. kernel-doc:: drivers/gpu/drm/drm_file.c :export: - Misc Utilities ============== |