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: 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: /sys/devices/.../power/state dev->power.power_state dpm_runtime_{suspend,resume)() 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: RAW driver (CONFIG_RAW_DRIVER) When: December 2005 Why: declared obsolete since kernel 2.6.3 O_DIRECT can be used instead Who: Adrian Bunk --------------------------- What: raw1394: requests of type RAW1394_REQ_ISO_SEND, RAW1394_REQ_ISO_LISTEN When: June 2007 Why: Deprecated in favour of the more efficient and robust rawiso interface. Affected are applications which use the deprecated part of libraw1394 (raw1394_iso_write, raw1394_start_iso_write, raw1394_start_iso_rcv, raw1394_stop_iso_rcv) or bypass libraw1394. Who: Dan Dennedy , Stefan Richter --------------------------- What: Video4Linux API 1 ioctls and video_decoder.h from Video devices. When: December 2006 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 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: drivers depending on OSS_OBSOLETE_DRIVER When: options in 2.6.20, code in 2.6.22 Why: OSS drivers with ALSA replacements Who: Adrian Bunk --------------------------- What: Usage of invalid timevals in setitimer When: March 2007 Why: POSIX requires to validate timevals in the setitimer call. This was never done by Linux. The invalid (e.g. negative timevals) were silently converted to more or less random timeouts and intervals. Until the removal a per boot limited number of warnings is printed and the timevals are sanitized. Who: Thomas Gleixner --------------------------- 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: 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: ACPI hooks (X86_SPEEDSTEP_CENTRINO_ACPI) in speedstep-centrino driver When: December 2006 Why: Speedstep-centrino driver with ACPI hooks and acpi-cpufreq driver are functionally very much similar. They talk to ACPI in same way. Only difference between them is the way they do frequency transitions. One uses MSRs and the other one uses IO ports. Functionaliy of speedstep_centrino with ACPI hooks is now merged into acpi-cpufreq. That means one common driver will support all Intel Enhanced Speedstep capable CPUs. That means less confusion over name of speedstep-centrino driver (with that driver supposed to be used on non-centrino platforms). That means less duplication of code and less maintenance effort and no possibility of these two drivers going out of sync. Current users of speedstep_centrino with ACPI hooks are requested to switch over to acpi-cpufreq driver. speedstep-centrino will continue to work using older non-ACPI static table based scheme even after this date. Who: Venkatesh Pallipadi --------------------------- 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: sk98lin network driver When: July 2007 Why: In kernel tree version of driver is unmaintained. Sk98lin driver replaced by the skge driver. Who: Stephen Hemminger --------------------------- 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: i8xx_tco watchdog driver When: in 2.6.22 Why: the i8xx_tco watchdog driver has been replaced by the iTCO_wdt watchdog driver. Who: Wim Van Sebroeck --------------------------- What: Multipath cached routing support in ipv4 When: in 2.6.23 Why: Code was merged, then submitter immediately disappeared leaving us with no maintainer and lots of bugs. The code should not have been merged in the first place, and many aspects of it's implementation are blocking more critical core networking development. It's marked EXPERIMENTAL and no distribution enables it because it cause obscure crashes due to unfixable bugs (interfaces don't return errors so memory allocation can't be handled, calling contexts of these interfaces make handling errors impossible too because they get called after we've totally commited to creating a route object, for example). This problem has existed for years and no forward progress has ever been made, and nobody steps up to try and salvage this code, so we're going to finally just get rid of it. Who: David S. Miller --------------------------- 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: drivers depending on OSS_OBSOLETE When: options in 2.6.23, code in 2.6.25 Why: obsolete OSS drivers Who: Adrian Bunk ---------------------------