kernel/linux.git/include/linux/nubus.h, branch v6.12.80

nubus: Make nubus_bus_type static and constant

2024-01-03T12:33:59+00:00

Now that the driver core can properly handle constant struct bus_type, move the nubus_bus_type variable to be a constant structure as well, placing it into read-only memory which can not be modified at runtime. It's also never used outside of drivers/nubus/bus.c so make it static and don't export it as no one is using it. Signed-off-by: Greg Kroah-Hartman Acked-by: Finn Thain Reviewed-by: Geert Uytterhoeven Link: https://lore.kernel.org/r/2023121940-enlarged-editor-c9a8@gregkh Signed-off-by: Geert Uytterhoeven

nubus: Don't list slot resources by default

2023-05-22T11:51:56+00:00

Some Nubus card ROMs contain many slot resources. A single Radius video card produced well over a thousand entries under /proc/bus/nubus/. Populating /proc/bus/nubus/ on a slow machine with several such cards installed takes long enough that the user may think that the system is wedged. All those procfs entries also consume significant RAM though they are not normally needed (except by developers). Omit these resources from /proc/bus/nubus/ by default and add a kernel parameter to enable them when needed. On the test machine, this saved 300 kB and 10 seconds. Cc: Brad Boyer Reviewed-by: Brad Boyer Tested-by: Stan Johnson Signed-off-by: Finn Thain Reviewed-by: Geert Uytterhoeven Link: https://lore.kernel.org/r/71ed7fb234a5f7381a50253b0d841a656d53e64c.1684200125.git.fthain@linux-m68k.org Signed-off-by: Geert Uytterhoeven

nubus: Make struct nubus_driver::remove return void

2021-07-28T13:33:59+00:00

The nubus core ignores the return value of the remove callback (in nubus_device_remove()) and all implementers return 0 anyway. So make it impossible for future drivers to return an unused error code by changing the remove prototype to return void. Signed-off-by: Uwe Kleine-König Acked-by: Finn Thain Link: https://lore.kernel.org/r/20210727080840.3550927-3-u.kleine-koenig@pengutronix.de Signed-off-by: Greg Kroah-Hartman

nubus: Call bus_register unconditionally

2018-05-14T14:27:08+00:00

Loading a NuBus driver module on a non-NuBus machine triggers the BUG_ON(!drv->bus->p) in driver_register(), because bus_register() was not called, because it is conditional on MACH_IS_MAC. Fix the crash by calling bus_register() unconditionally. Call it from a postcore_initcall(), like other busses do. Hence, the bus type is available for device_register(), which happens in a subsys initcall, and for driver_register(), which happens in a device or module initcall. Cc: Greg Kroah-Hartman Reported-by: Michael Schmitz Tested-by: Stan Johnson Fixes: 7f86c765a6a2 ("nubus: Add support for the driver model") Signed-off-by: Finn Thain Reviewed-by: Geert Uytterhoeven Signed-off-by: Greg Kroah-Hartman

nubus: Add support for the driver model

2018-01-16T15:47:29+00:00

This patch brings basic support for the Linux Driver Model to the NuBus subsystem. For flexibility, the matching of boards with drivers is left up to the drivers. This is also the approach taken by NetBSD. A board may have many functions, and drivers may have to consider many functional resources and board resources in order to match a device. This implementation does not bind drivers to resources (nor does it bind many drivers to the same board). Apple's NuBus declaration ROM design is flexible enough to allow that, but I don't see a need to support it as we don't use the "slot zero" resources (in the main logic board ROM). Eliminate the global nubus_boards linked list by rewriting the procfs board iterator around bus_for_each_dev(). Hence the nubus device refcount can be used to determine the lifespan of board objects. Cc: Greg Kroah-Hartman Reviewed-by: Greg Kroah-Hartman Tested-by: Stan Johnson Signed-off-by: Finn Thain Signed-off-by: Geert Uytterhoeven

nubus: Adopt standard linked list implementation

2018-01-16T15:47:29+00:00

This increases code re-use and improves readability. Cc: "David S. Miller" Cc: Bartlomiej Zolnierkiewicz Acked-by: Bartlomiej Zolnierkiewicz Tested-by: Stan Johnson Signed-off-by: Finn Thain Signed-off-by: Geert Uytterhoeven

nubus: Rename struct nubus_dev

2018-01-16T15:47:29+00:00

It is misleading to call a functional resource a "device". In adopting the Linux Driver Model, the struct device will be embedded in struct nubus_board. That will compound the terminlogy problem because drivers will bind with boards, not with functional resources. Avoid this by renaming struct nubus_dev as struct nubus_rsrc. "Functional resource" is the vendor's terminology so this helps avoid confusion. Cc: "David S. Miller" Cc: Bartlomiej Zolnierkiewicz Acked-by: Bartlomiej Zolnierkiewicz Tested-by: Stan Johnson Signed-off-by: Finn Thain Signed-off-by: Geert Uytterhoeven

nubus: Rework /proc/bus/nubus/s/ implementation

2018-01-16T15:47:29+00:00

The /proc/bus/nubus/s/ directory tree for any slot s is missing a lot of information. The struct file_operations methods have long been left unimplemented (hence the familiar compile-time warning, "Need to set some I/O handlers here"). Slot resources have a complex structure which varies depending on board function. The logic for interpreting these ROM data structures is found in nubus.c. Let's not duplicate that logic in proc.c. Create the /proc/bus/nubus/s/ inodes while scanning slot s. During descent through slot resource subdirectories, call the new nubus_proc_add_foo() functions to create the procfs inodes. Also add a new function, nubus_seq_write_rsrc_mem(), to write the contents of a particular slot resource to a given seq_file. This is used by the procfs file_operations methods, to finally give userspace access to slot ROM information, such as the available video modes. Tested-by: Stan Johnson Signed-off-by: Finn Thain Signed-off-by: Geert Uytterhoeven

nubus: Clean up whitespace

2018-01-16T15:47:29+00:00

Tested-by: Stan Johnson Signed-off-by: Finn Thain Signed-off-by: Geert Uytterhoeven

nubus: Remove redundant code

2018-01-16T15:47:29+00:00

Eliminate unused values from struct nubus_dev to save wasted memory (a Radius PrecisionColor 24X card has about 95 functional resources and up to six such cards may be fitted). Also remove redundant static variable initialization, an unreachable !MACH_IS_MAC conditional, the unused nubus_find_device() function, the bogus get_nubus_list() prototype and the pointless card_present temporary variable. Tested-by: Stan Johnson Signed-off-by: Finn Thain Signed-off-by: Geert Uytterhoeven