Documentation/feature-removal-schedule.txt

   1 The following is a list of files and features that are going to be
   2 removed in the kernel source tree.  Every entry should contain what
   3 exactly is going away, why it is happening, and who is going to be doing
   4 the work.  When the feature is removed from the kernel, it should also
   5 be removed from this file.
   6
   7 ---------------------------
   8
   9 What:   MXSER
  10 When:   December 2007
  11 Why:    Old mxser driver is obsoleted by the mxser_new. Give it some time yet
  12         and remove it.
  13 Who:    Jiri Slaby <jirislaby@gmail.com>
  14
  15 ---------------------------
  16
  17 What:   V4L2 VIDIOC_G_MPEGCOMP and VIDIOC_S_MPEGCOMP
  18 When:   October 2007
  19 Why:    Broken attempt to set MPEG compression parameters. These ioctls are
  20         not able to implement the wide variety of parameters that can be set
  21         by hardware MPEG encoders. A new MPEG control mechanism was created
  22         in kernel 2.6.18 that replaces these ioctls. See the V4L2 specification
  23         (section 1.9: Extended controls) for more information on this topic.
  24 Who:    Hans Verkuil <hverkuil@xs4all.nl> and
  25         Mauro Carvalho Chehab <mchehab@infradead.org>
  26
  27 ---------------------------
  28
  29 What:   /sys/devices/.../power/state
  30         dev->power.power_state
  31         dpm_runtime_{suspend,resume)()
  32 When:   July 2007
  33 Why:    Broken design for runtime control over driver power states, confusing
  34         driver-internal runtime power management with:  mechanisms to support
  35         system-wide sleep state transitions; event codes that distinguish
  36         different phases of swsusp "sleep" transitions; and userspace policy
  37         inputs.  This framework was never widely used, and most attempts to
  38         use it were broken.  Drivers should instead be exposing domain-specific
  39         interfaces either to kernel or to userspace.
  40 Who:    Pavel Machek <pavel@suse.cz>
  41
  42 ---------------------------
  43
  44 What:   RAW driver (CONFIG_RAW_DRIVER)
  45 When:   December 2005
  46 Why:    declared obsolete since kernel 2.6.3
  47         O_DIRECT can be used instead
  48 Who:    Adrian Bunk <bunk@stusta.de>
  49
  50 ---------------------------
  51
  52 What:   raw1394: requests of type RAW1394_REQ_ISO_SEND, RAW1394_REQ_ISO_LISTEN
  53 When:   June 2007
  54 Why:    Deprecated in favour of the more efficient and robust rawiso interface.
  55         Affected are applications which use the deprecated part of libraw1394
  56         (raw1394_iso_write, raw1394_start_iso_write, raw1394_start_iso_rcv,
  57         raw1394_stop_iso_rcv) or bypass libraw1394.
  58 Who:    Dan Dennedy <dan@dennedy.org>, Stefan Richter <stefanr@s5r6.in-berlin.de>
  59
  60 ---------------------------
  61
  62 What:   Video4Linux API 1 ioctls and video_decoder.h from Video devices.
  63 When:   December 2006
  64 Why:    V4L1 AP1 was replaced by V4L2 API. during migration from 2.4 to 2.6
  65         series. The old API have lots of drawbacks and don't provide enough
  66         means to work with all video and audio standards. The newer API is
  67         already available on the main drivers and should be used instead.
  68         Newer drivers should use v4l_compat_translate_ioctl function to handle
  69         old calls, replacing to newer ones.
  70         Decoder iocts are using internally to allow video drivers to
  71         communicate with video decoders. This should also be improved to allow
  72         V4L2 calls being translated into compatible internal ioctls.
  73 Who:    Mauro Carvalho Chehab <mchehab@brturbo.com.br>
  74
  75 ---------------------------
  76
  77 What:   PCMCIA control ioctl (needed for pcmcia-cs [cardmgr, cardctl])
  78 When:   November 2005
  79 Files:  drivers/pcmcia/: pcmcia_ioctl.c
  80 Why:    With the 16-bit PCMCIA subsystem now behaving (almost) like a
  81         normal hotpluggable bus, and with it using the default kernel
  82         infrastructure (hotplug, driver core, sysfs) keeping the PCMCIA
  83         control ioctl needed by cardmgr and cardctl from pcmcia-cs is
  84         unnecessary, and makes further cleanups and integration of the
  85         PCMCIA subsystem into the Linux kernel device driver model more
  86         difficult. The features provided by cardmgr and cardctl are either
  87         handled by the kernel itself now or are available in the new
  88         pcmciautils package available at
  89         http://kernel.org/pub/linux/utils/kernel/pcmcia/
  90 Who:    Dominik Brodowski <linux@brodo.de>
  91
  92 ---------------------------
  93
  94 What:   remove EXPORT_SYMBOL(kernel_thread)
  95 When:   August 2006
  96 Files:  arch/*/kernel/*_ksyms.c
  97 Why:    kernel_thread is a low-level implementation detail.  Drivers should
  98         use the <linux/kthread.h> API instead which shields them from
  99         implementation details and provides a higherlevel interface that
 100         prevents bugs and code duplication
 101 Who:    Christoph Hellwig <hch@lst.de>
 102
 103 ---------------------------
 104
 105 What:   CONFIG_FORCED_INLINING
 106 When:   June 2006
 107 Why:    Config option is there to see if gcc is good enough. (in january
 108         2006). If it is, the behavior should just be the default. If it's not,
 109         the option should just go away entirely.
 110 Who:    Arjan van de Ven
 111
 112 ---------------------------
 113
 114 What:   eepro100 network driver
 115 When:   January 2007
 116 Why:    replaced by the e100 driver
 117 Who:    Adrian Bunk <bunk@stusta.de>
 118
 119 ---------------------------
 120
 121 What:  drivers depending on OSS_OBSOLETE_DRIVER
 122 When:  options in 2.6.20, code in 2.6.22
 123 Why:   OSS drivers with ALSA replacements
 124 Who:   Adrian Bunk <bunk@stusta.de>
 125
 126 ---------------------------
 127
 128 What:   Unused EXPORT_SYMBOL/EXPORT_SYMBOL_GPL exports
 129         (temporary transition config option provided until then)
 130         The transition config option will also be removed at the same time.
 131 When:   before 2.6.19
 132 Why:    Unused symbols are both increasing the size of the kernel binary
 133         and are often a sign of "wrong API"
 134 Who:    Arjan van de Ven <arjan@linux.intel.com>
 135
 136 ---------------------------
 137
 138 What:   USB driver API moves to EXPORT_SYMBOL_GPL
 139 When:   February 2008
 140 Files:  include/linux/usb.h, drivers/usb/core/driver.c
 141 Why:    The USB subsystem has changed a lot over time, and it has been
 142         possible to create userspace USB drivers using usbfs/libusb/gadgetfs
 143         that operate as fast as the USB bus allows.  Because of this, the USB
 144         subsystem will not be allowing closed source kernel drivers to
 145         register with it, after this grace period is over.  If anyone needs
 146         any help in converting their closed source drivers over to use the
 147         userspace filesystems, please contact the
 148         linux-usb-devel@lists.sourceforge.net mailing list, and the developers
 149         there will be glad to help you out.
 150 Who:    Greg Kroah-Hartman <gregkh@suse.de>
 151
 152 ---------------------------
 153
 154 What:   Interrupt only SA_* flags
 155 When:   September 2007
 156 Why:    The interrupt related SA_* flags are replaced by IRQF_* to move them
 157         out of the signal namespace.
 158
 159 Who:    Thomas Gleixner <tglx@linutronix.de>
 160
 161 ---------------------------
 162
 163 What:   PHYSDEVPATH, PHYSDEVBUS, PHYSDEVDRIVER in the uevent environment
 164 When:   October 2008
 165 Why:    The stacking of class devices makes these values misleading and
 166         inconsistent.
 167         Class devices should not carry any of these properties, and bus
 168         devices have SUBSYTEM and DRIVER as a replacement.
 169 Who:    Kay Sievers <kay.sievers@suse.de>
 170
 171 ---------------------------
 172
 173 What:   i2c-isa
 174 When:   December 2006
 175 Why:    i2c-isa is a non-sense and doesn't fit in the device driver
 176         model. Drivers relying on it are better implemented as platform
 177         drivers.
 178 Who:    Jean Delvare <khali@linux-fr.org>
 179
 180 ---------------------------
 181
 182 What:   i2c_adapter.list
 183 When:   July 2007
 184 Why:    Superfluous, this list duplicates the one maintained by the driver
 185         core.
 186 Who:    Jean Delvare <khali@linux-fr.org>,
 187         David Brownell <dbrownell@users.sourceforge.net>
 188
 189 ---------------------------
 190
 191 What:  drivers depending on OBSOLETE_OSS
 192 When:  options in 2.6.22, code in 2.6.24
 193 Why:   OSS drivers with ALSA replacements
 194 Who:   Adrian Bunk <bunk@stusta.de>
 195
 196 ---------------------------
 197
 198 What:   ACPI hooks (X86_SPEEDSTEP_CENTRINO_ACPI) in speedstep-centrino driver
 199 When:   December 2006
 200 Why:    Speedstep-centrino driver with ACPI hooks and acpi-cpufreq driver are
 201         functionally very much similar. They talk to ACPI in same way. Only
 202         difference between them is the way they do frequency transitions.
 203         One uses MSRs and the other one uses IO ports. Functionaliy of
 204         speedstep_centrino with ACPI hooks is now merged into acpi-cpufreq.
 205         That means one common driver will support all Intel Enhanced Speedstep
 206         capable CPUs. That means less confusion over name of
 207         speedstep-centrino driver (with that driver supposed to be used on
 208         non-centrino platforms). That means less duplication of code and
 209         less maintenance effort and no possibility of these two drivers
 210         going out of sync.
 211         Current users of speedstep_centrino with ACPI hooks are requested to
 212         switch over to acpi-cpufreq driver. speedstep-centrino will continue
 213         to work using older non-ACPI static table based scheme even after this
 214         date.
 215
 216 Who:    Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
 217
 218 ---------------------------
 219
 220 What:   /sys/firmware/acpi/namespace
 221 When:   2.6.21
 222 Why:    The ACPI namespace is effectively the symbol list for
 223         the BIOS.  The device names are completely arbitrary
 224         and have no place being exposed to user-space.
 225
 226         For those interested in the BIOS ACPI namespace,
 227         the BIOS can be extracted and disassembled with acpidump
 228         and iasl as documented in the pmtools package here:
 229         http://ftp.kernel.org/pub/linux/kernel/people/lenb/acpi/utils
 230 Who:    Len Brown <len.brown@intel.com>
 231
 232 ---------------------------
 233
 234 What:   ACPI procfs interface
 235 When:   July 2007
 236 Why:    After ACPI sysfs conversion, ACPI attributes will be duplicated
 237         in sysfs and the ACPI procfs interface should be removed.
 238 Who:    Zhang Rui <rui.zhang@intel.com>
 239
 240 ---------------------------
 241
 242 What:   /proc/acpi/button
 243 When:   August 2007
 244 Why:    /proc/acpi/button has been replaced by events to the input layer
 245         since 2.6.20.
 246 Who:    Len Brown <len.brown@intel.com>
 247
 248 ---------------------------
 249
 250 What:   sk98lin network driver
 251 When:   July 2007
 252 Why:    In kernel tree version of driver is unmaintained. Sk98lin driver
 253         replaced by the skge driver.
 254 Who:    Stephen Hemminger <shemminger@osdl.org>
 255
 256 ---------------------------
 257
 258 What:   Compaq touchscreen device emulation
 259 When:   Oct 2007
 260 Files:  drivers/input/tsdev.c
 261 Why:    The code says it was obsolete when it was written in 2001.
 262         tslib is a userspace library which does anything tsdev can do and
 263         much more besides in userspace where this code belongs. There is no
 264         longer any need for tsdev and applications should have converted to
 265         use tslib by now.
 266         The name "tsdev" is also extremely confusing and lots of people have
 267         it loaded when they don't need/use it.
 268 Who:    Richard Purdie <rpurdie@rpsys.net>
 269
 270 ---------------------------
 271
 272 What:   i8xx_tco watchdog driver
 273 When:   in 2.6.22
 274 Why:    the i8xx_tco watchdog driver has been replaced by the iTCO_wdt
 275         watchdog driver.
 276 Who:    Wim Van Sebroeck <wim@iguana.be>
 277
 278 ---------------------------
 279
 280 What:   Multipath cached routing support in ipv4
 281 When:   in 2.6.23
 282 Why:    Code was merged, then submitter immediately disappeared leaving
 283         us with no maintainer and lots of bugs.  The code should not have
 284         been merged in the first place, and many aspects of it's
 285         implementation are blocking more critical core networking
 286         development.  It's marked EXPERIMENTAL and no distribution
 287         enables it because it cause obscure crashes due to unfixable bugs
 288         (interfaces don't return errors so memory allocation can't be
 289         handled, calling contexts of these interfaces make handling
 290         errors impossible too because they get called after we've
 291         totally commited to creating a route object, for example).
 292         This problem has existed for years and no forward progress
 293         has ever been made, and nobody steps up to try and salvage
 294         this code, so we're going to finally just get rid of it.
 295 Who:    David S. Miller <davem@davemloft.net>
 296
 297 ---------------------------
 298
 299 What:   read_dev_chars(), read_conf_data{,_lpm}() (s390 common I/O layer)
 300 When:   December 2007
 301 Why:    These functions are a leftover from 2.4 times. They have several
 302         problems:
 303         - Duplication of checks that are done in the device driver's
 304           interrupt handler
 305         - common I/O layer can't do device specific error recovery
 306         - device driver can't be notified for conditions happening during
 307           execution of the function
 308         Device drivers should issue the read device characteristics and read
 309         configuration data ccws and do the appropriate error handling
 310         themselves.
 311 Who:    Cornelia Huck <cornelia.huck@de.ibm.com>
 312
 313 ---------------------------
 314
 315 What:   i2c-ixp2000, i2c-ixp4xx and scx200_i2c drivers
 316 When:   September 2007
 317 Why:    Obsolete. The new i2c-gpio driver replaces all hardware-specific
 318         I2C-over-GPIO drivers.
 319 Who:    Jean Delvare <khali@linux-fr.org>
 320
 321 ---------------------------
 322
 323 What:  drivers depending on OSS_OBSOLETE
 324 When:  options in 2.6.23, code in 2.6.25
 325 Why:   obsolete OSS drivers
 326 Who:   Adrian Bunk <bunk@stusta.de>
 327
 328 ---------------------------
 329