The following is a list of files and features that are going to be removed in the kernel source tree. Every entry should contain what exactly is going away, why it is happening, and who is going to be doing the work. When the feature is removed from the kernel, it should also be removed from this file. --------------------------- What: MXSER When: December 2007 Why: Old mxser driver is obsoleted by the mxser_new. Give it some time yet and remove it. Who: Jiri Slaby --------------------------- What: V4L2 VIDIOC_G_MPEGCOMP and VIDIOC_S_MPEGCOMP When: October 2007 Why: Broken attempt to set MPEG compression parameters. These ioctls are not able to implement the wide variety of parameters that can be set by hardware MPEG encoders. A new MPEG control mechanism was created in kernel 2.6.18 that replaces these ioctls. See the V4L2 specification (section 1.9: Extended controls) for more information on this topic. Who: Hans Verkuil and Mauro Carvalho Chehab --------------------------- What: dev->power.power_state When: July 2007 Why: Broken design for runtime control over driver power states, confusing driver-internal runtime power management with: mechanisms to support system-wide sleep state transitions; event codes that distinguish different phases of swsusp "sleep" transitions; and userspace policy inputs. This framework was never widely used, and most attempts to use it were broken. Drivers should instead be exposing domain-specific interfaces either to kernel or to userspace. Who: Pavel Machek --------------------------- What: old NCR53C9x driver When: October 2007 Why: Replaced by the much better esp_scsi driver. Actual low-level driver can be ported over almost trivially. Who: David Miller Christoph Hellwig --------------------------- What: Video4Linux API 1 ioctls and video_decoder.h from Video devices. When: December 2006 Files: include/linux/video_decoder.h Why: V4L1 AP1 was replaced by V4L2 API. during migration from 2.4 to 2.6 series. The old API have lots of drawbacks and don't provide enough means to work with all video and audio standards. The newer API is already available on the main drivers and should be used instead. Newer drivers should use v4l_compat_translate_ioctl function to handle old calls, replacing to newer ones. Decoder iocts are using internally to allow video drivers to communicate with video decoders. This should also be improved to allow V4L2 calls being translated into compatible internal ioctls. Who: Mauro Carvalho Chehab --------------------------- What: PCMCIA control ioctl (needed for pcmcia-cs [cardmgr, cardctl]) When: November 2005 Files: drivers/pcmcia/: pcmcia_ioctl.c Why: With the 16-bit PCMCIA subsystem now behaving (almost) like a normal hotpluggable bus, and with it using the default kernel infrastructure (hotplug, driver core, sysfs) keeping the PCMCIA control ioctl needed by cardmgr and cardctl from pcmcia-cs is unnecessary, and makes further cleanups and integration of the PCMCIA subsystem into the Linux kernel device driver model more difficult. The features provided by cardmgr and cardctl are either handled by the kernel itself now or are available in the new pcmciautils package available at http://kernel.org/pub/linux/utils/kernel/pcmcia/ Who: Dominik Brodowski --------------------------- What: remove EXPORT_SYMBOL(kernel_thread) When: August 2006 Files: arch/*/kernel/*_ksyms.c Funcs: kernel_thread Why: kernel_thread is a low-level implementation detail. Drivers should use the API instead which shields them from implementation details and provides a higherlevel interface that prevents bugs and code duplication Who: Christoph Hellwig --------------------------- What: CONFIG_FORCED_INLINING When: June 2006 Why: Config option is there to see if gcc is good enough. (in january 2006). If it is, the behavior should just be the default. If it's not, the option should just go away entirely. Who: Arjan van de Ven --------------------------- What: eepro100 network driver When: January 2007 Why: replaced by the e100 driver Who: Adrian Bunk --------------------------- What: Unused EXPORT_SYMBOL/EXPORT_SYMBOL_GPL exports (temporary transition config option provided until then) The transition config option will also be removed at the same time. When: before 2.6.19 Why: Unused symbols are both increasing the size of the kernel binary and are often a sign of "wrong API" Who: Arjan van de Ven --------------------------- What: USB driver API moves to EXPORT_SYMBOL_GPL When: February 2008 Files: include/linux/usb.h, drivers/usb/core/driver.c Why: The USB subsystem has changed a lot over time, and it has been possible to create userspace USB drivers using usbfs/libusb/gadgetfs that operate as fast as the USB bus allows. Because of this, the USB subsystem will not be allowing closed source kernel drivers to register with it, after this grace period is over. If anyone needs any help in converting their closed source drivers over to use the userspace filesystems, please contact the linux-usb-devel@lists.sourceforge.net mailing list, and the developers there will be glad to help you out. Who: Greg Kroah-Hartman --------------------------- What: filemap_nopage, filemap_populate When: April 2007 Why: These legacy interfaces no longer have any callers in the kernel and any functionality provided can be provided with filemap_fault. The removal schedule is short because they are a big maintainence burden and have some bugs. Who: Nick Piggin --------------------------- What: vm_ops.populate, install_page When: April 2007 Why: These legacy interfaces no longer have any callers in the kernel and any functionality provided can be provided with vm_ops.fault. Who: Nick Piggin --------------------------- What: vm_ops.nopage When: February 2008, provided in-kernel callers have been converted Why: This interface is replaced by vm_ops.fault, but it has been around forever, is used by a lot of drivers, and doesn't cost much to maintain. Who: Nick Piggin --------------------------- What: Interrupt only SA_* flags When: September 2007 Why: The interrupt related SA_* flags are replaced by IRQF_* to move them out of the signal namespace. Who: Thomas Gleixner --------------------------- What: PHYSDEVPATH, PHYSDEVBUS, PHYSDEVDRIVER in the uevent environment When: October 2008 Why: The stacking of class devices makes these values misleading and inconsistent. Class devices should not carry any of these properties, and bus devices have SUBSYTEM and DRIVER as a replacement. Who: Kay Sievers --------------------------- What: i2c-isa When: December 2006 Why: i2c-isa is a non-sense and doesn't fit in the device driver model. Drivers relying on it are better implemented as platform drivers. Who: Jean Delvare --------------------------- What: i2c_adapter.list When: July 2007 Why: Superfluous, this list duplicates the one maintained by the driver core. Who: Jean Delvare , David Brownell --------------------------- What: drivers depending on OBSOLETE_OSS When: options in 2.6.22, code in 2.6.24 Why: OSS drivers with ALSA replacements Who: Adrian Bunk --------------------------- What: /sys/firmware/acpi/namespace When: 2.6.21 Why: The ACPI namespace is effectively the symbol list for the BIOS. The device names are completely arbitrary and have no place being exposed to user-space. For those interested in the BIOS ACPI namespace, the BIOS can be extracted and disassembled with acpidump and iasl as documented in the pmtools package here: http://ftp.kernel.org/pub/linux/kernel/people/lenb/acpi/utils Who: Len Brown --------------------------- What: ACPI procfs interface When: July 2007 Why: After ACPI sysfs conversion, ACPI attributes will be duplicated in sysfs and the ACPI procfs interface should be removed. Who: Zhang Rui --------------------------- What: /proc/acpi/button When: August 2007 Why: /proc/acpi/button has been replaced by events to the input layer since 2.6.20. Who: Len Brown --------------------------- What: Compaq touchscreen device emulation When: Oct 2007 Files: drivers/input/tsdev.c Why: The code says it was obsolete when it was written in 2001. tslib is a userspace library which does anything tsdev can do and much more besides in userspace where this code belongs. There is no longer any need for tsdev and applications should have converted to use tslib by now. The name "tsdev" is also extremely confusing and lots of people have it loaded when they don't need/use it. Who: Richard Purdie --------------------------- What: read_dev_chars(), read_conf_data{,_lpm}() (s390 common I/O layer) When: December 2007 Why: These functions are a leftover from 2.4 times. They have several problems: - Duplication of checks that are done in the device driver's interrupt handler - common I/O layer can't do device specific error recovery - device driver can't be notified for conditions happening during execution of the function Device drivers should issue the read device characteristics and read configuration data ccws and do the appropriate error handling themselves. Who: Cornelia Huck --------------------------- What: i2c-ixp2000, i2c-ixp4xx and scx200_i2c drivers When: September 2007 Why: Obsolete. The new i2c-gpio driver replaces all hardware-specific I2C-over-GPIO drivers. Who: Jean Delvare --------------------------- What: 'time' kernel boot parameter When: January 2008 Why: replaced by 'printk.time=' so that printk timestamps can be enabled or disabled as needed Who: Randy Dunlap --------------------------- What: drivers depending on OSS_OBSOLETE When: options in 2.6.23, code in 2.6.25 Why: obsolete OSS drivers Who: Adrian Bunk --------------------------- What: libata spindown skipping and warning When: Dec 2008 Why: Some halt(8) implementations synchronize caches for and spin down libata disks because libata didn't use to spin down disk on system halt (only synchronized caches). Spin down on system halt is now implemented. sysfs node /sys/class/scsi_disk/h:c:i:l/manage_start_stop is present if spin down support is available. Because issuing spin down command to an already spun down disk makes some disks spin up just to spin down again, libata tracks device spindown status to skip the extra spindown command and warn about it. This is to give userspace tools the time to get updated and will be removed after userspace is reasonably updated. Who: Tejun Heo --------------------------- What: Legacy RTC drivers (under drivers/i2c/chips) When: November 2007 Why: Obsolete. We have a RTC subsystem with better drivers. Who: Jean Delvare --------------------------- What: iptables SAME target When: 1.1. 2008 Files: net/ipv4/netfilter/ipt_SAME.c, include/linux/netfilter_ipv4/ipt_SAME.h Why: Obsolete for multiple years now, NAT core provides the same behaviour. Unfixable broken wrt. 32/64 bit cleanness. Who: Patrick McHardy --------------------------- What: The arch/ppc and include/asm-ppc directories When: Jun 2008 Why: The arch/powerpc tree is the merged architecture for ppc32 and ppc64 platforms. Currently there are efforts underway to port the remaining arch/ppc platforms to the merged tree. New submissions to the arch/ppc tree have been frozen with the 2.6.22 kernel release and that tree will remain in bug-fix only mode until its scheduled removal. Platforms that are not ported by June 2008 will be removed due to the lack of an interested maintainer. Who: linuxppc-dev@ozlabs.org --------------------------- What: mthca driver's MSI support When: January 2008 Files: drivers/infiniband/hw/mthca/*.[ch] Why: All mthca hardware also supports MSI-X, which provides strictly more functionality than MSI. So there is no point in having both MSI-X and MSI support in the driver. Who: Roland Dreier ---------------------------