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:   old NCR53C9x driver
  63 When:   October 2007
  64 Why:    Replaced by the much better esp_scsi driver.  Actual low-level
  65         driver can be ported over almost trivially.
  66 Who:    David Miller <davem@davemloft.net>
  67         Christoph Hellwig <hch@lst.de>
  68
  69 ---------------------------
  70
  71 What:   Video4Linux API 1 ioctls and video_decoder.h from Video devices.
  72 When:   December 2006
  73 Files:  include/linux/video_decoder.h
  74 Why:    V4L1 AP1 was replaced by V4L2 API. during migration from 2.4 to 2.6
  75         series. The old API have lots of drawbacks and don't provide enough
  76         means to work with all video and audio standards. The newer API is
  77         already available on the main drivers and should be used instead.
  78         Newer drivers should use v4l_compat_translate_ioctl function to handle
  79         old calls, replacing to newer ones.
  80         Decoder iocts are using internally to allow video drivers to
  81         communicate with video decoders. This should also be improved to allow
  82         V4L2 calls being translated into compatible internal ioctls.
  83 Who:    Mauro Carvalho Chehab <mchehab@brturbo.com.br>
  84
  85 ---------------------------
  86
  87 What:   PCMCIA control ioctl (needed for pcmcia-cs [cardmgr, cardctl])
  88 When:   November 2005
  89 Files:  drivers/pcmcia/: pcmcia_ioctl.c
  90 Why:    With the 16-bit PCMCIA subsystem now behaving (almost) like a
  91         normal hotpluggable bus, and with it using the default kernel
  92         infrastructure (hotplug, driver core, sysfs) keeping the PCMCIA
  93         control ioctl needed by cardmgr and cardctl from pcmcia-cs is
  94         unnecessary, and makes further cleanups and integration of the
  95         PCMCIA subsystem into the Linux kernel device driver model more
  96         difficult. The features provided by cardmgr and cardctl are either
  97         handled by the kernel itself now or are available in the new
  98         pcmciautils package available at
  99         http://kernel.org/pub/linux/utils/kernel/pcmcia/
 100 Who:    Dominik Brodowski <linux@brodo.de>
 101
 102 ---------------------------
 103
 104 What:   remove EXPORT_SYMBOL(kernel_thread)
 105 When:   August 2006
 106 Files:  arch/*/kernel/*_ksyms.c
 107 Why:    kernel_thread is a low-level implementation detail.  Drivers should
 108         use the <linux/kthread.h> API instead which shields them from
 109         implementation details and provides a higherlevel interface that
 110         prevents bugs and code duplication
 111 Who:    Christoph Hellwig <hch@lst.de>
 112
 113 ---------------------------
 114
 115 What:   CONFIG_FORCED_INLINING
 116 When:   June 2006
 117 Why:    Config option is there to see if gcc is good enough. (in january
 118         2006). If it is, the behavior should just be the default. If it's not,
 119         the option should just go away entirely.
 120 Who:    Arjan van de Ven
 121
 122 ---------------------------
 123
 124 What:   eepro100 network driver
 125 When:   January 2007
 126 Why:    replaced by the e100 driver
 127 Who:    Adrian Bunk <bunk@stusta.de>
 128
 129 ---------------------------
 130
 131 What:  drivers depending on OSS_OBSOLETE_DRIVER
 132 When:  options in 2.6.20, code in 2.6.22
 133 Why:   OSS drivers with ALSA replacements
 134 Who:   Adrian Bunk <bunk@stusta.de>
 135
 136 ---------------------------
 137
 138 What:   Unused EXPORT_SYMBOL/EXPORT_SYMBOL_GPL exports
 139         (temporary transition config option provided until then)
 140         The transition config option will also be removed at the same time.
 141 When:   before 2.6.19
 142 Why:    Unused symbols are both increasing the size of the kernel binary
 143         and are often a sign of "wrong API"
 144 Who:    Arjan van de Ven <arjan@linux.intel.com>
 145
 146 ---------------------------
 147
 148 What:   USB driver API moves to EXPORT_SYMBOL_GPL
 149 When:   February 2008
 150 Files:  include/linux/usb.h, drivers/usb/core/driver.c
 151 Why:    The USB subsystem has changed a lot over time, and it has been
 152         possible to create userspace USB drivers using usbfs/libusb/gadgetfs
 153         that operate as fast as the USB bus allows.  Because of this, the USB
 154         subsystem will not be allowing closed source kernel drivers to
 155         register with it, after this grace period is over.  If anyone needs
 156         any help in converting their closed source drivers over to use the
 157         userspace filesystems, please contact the
 158         linux-usb-devel@lists.sourceforge.net mailing list, and the developers
 159         there will be glad to help you out.
 160 Who:    Greg Kroah-Hartman <gregkh@suse.de>
 161
 162 ---------------------------
 163
 164 What:   Interrupt only SA_* flags
 165 When:   September 2007
 166 Why:    The interrupt related SA_* flags are replaced by IRQF_* to move them
 167         out of the signal namespace.
 168
 169 Who:    Thomas Gleixner <tglx@linutronix.de>
 170
 171 ---------------------------
 172
 173 What:   PHYSDEVPATH, PHYSDEVBUS, PHYSDEVDRIVER in the uevent environment
 174 When:   October 2008
 175 Why:    The stacking of class devices makes these values misleading and
 176         inconsistent.
 177         Class devices should not carry any of these properties, and bus
 178         devices have SUBSYTEM and DRIVER as a replacement.
 179 Who:    Kay Sievers <kay.sievers@suse.de>
 180
 181 ---------------------------
 182
 183 What:   i2c-isa
 184 When:   December 2006
 185 Why:    i2c-isa is a non-sense and doesn't fit in the device driver
 186         model. Drivers relying on it are better implemented as platform
 187         drivers.
 188 Who:    Jean Delvare <khali@linux-fr.org>
 189
 190 ---------------------------
 191
 192 What:   i2c_adapter.list
 193 When:   July 2007
 194 Why:    Superfluous, this list duplicates the one maintained by the driver
 195         core.
 196 Who:    Jean Delvare <khali@linux-fr.org>,
 197         David Brownell <dbrownell@users.sourceforge.net>
 198
 199 ---------------------------
 200
 201 What:  drivers depending on OBSOLETE_OSS
 202 When:  options in 2.6.22, code in 2.6.24
 203 Why:   OSS drivers with ALSA replacements
 204 Who:   Adrian Bunk <bunk@stusta.de>
 205
 206 ---------------------------
 207
 208 What:   ACPI hooks (X86_SPEEDSTEP_CENTRINO_ACPI) in speedstep-centrino driver
 209 When:   December 2006
 210 Why:    Speedstep-centrino driver with ACPI hooks and acpi-cpufreq driver are
 211         functionally very much similar. They talk to ACPI in same way. Only
 212         difference between them is the way they do frequency transitions.
 213         One uses MSRs and the other one uses IO ports. Functionaliy of
 214         speedstep_centrino with ACPI hooks is now merged into acpi-cpufreq.
 215         That means one common driver will support all Intel Enhanced Speedstep
 216         capable CPUs. That means less confusion over name of
 217         speedstep-centrino driver (with that driver supposed to be used on
 218         non-centrino platforms). That means less duplication of code and
 219         less maintenance effort and no possibility of these two drivers
 220         going out of sync.
 221         Current users of speedstep_centrino with ACPI hooks are requested to
 222         switch over to acpi-cpufreq driver. speedstep-centrino will continue
 223         to work using older non-ACPI static table based scheme even after this
 224         date.
 225
 226 Who:    Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
 227
 228 ---------------------------
 229
 230 What:   /sys/firmware/acpi/namespace
 231 When:   2.6.21
 232 Why:    The ACPI namespace is effectively the symbol list for
 233         the BIOS.  The device names are completely arbitrary
 234         and have no place being exposed to user-space.
 235
 236         For those interested in the BIOS ACPI namespace,
 237         the BIOS can be extracted and disassembled with acpidump
 238         and iasl as documented in the pmtools package here:
 239         http://ftp.kernel.org/pub/linux/kernel/people/lenb/acpi/utils
 240 Who:    Len Brown <len.brown@intel.com>
 241
 242 ---------------------------
 243
 244 What:   ACPI procfs interface
 245 When:   July 2007
 246 Why:    After ACPI sysfs conversion, ACPI attributes will be duplicated
 247         in sysfs and the ACPI procfs interface should be removed.
 248 Who:    Zhang Rui <rui.zhang@intel.com>
 249
 250 ---------------------------
 251
 252 What:   /proc/acpi/button
 253 When:   August 2007
 254 Why:    /proc/acpi/button has been replaced by events to the input layer
 255         since 2.6.20.
 256 Who:    Len Brown <len.brown@intel.com>
 257
 258 ---------------------------
 259
 260 What:   sk98lin network driver
 261 When:   July 2007
 262 Why:    In kernel tree version of driver is unmaintained. Sk98lin driver
 263         replaced by the skge driver.
 264 Who:    Stephen Hemminger <shemminger@osdl.org>
 265
 266 ---------------------------
 267
 268 What:   Compaq touchscreen device emulation
 269 When:   Oct 2007
 270 Files:  drivers/input/tsdev.c
 271 Why:    The code says it was obsolete when it was written in 2001.
 272         tslib is a userspace library which does anything tsdev can do and
 273         much more besides in userspace where this code belongs. There is no
 274         longer any need for tsdev and applications should have converted to
 275         use tslib by now.
 276         The name "tsdev" is also extremely confusing and lots of people have
 277         it loaded when they don't need/use it.
 278 Who:    Richard Purdie <rpurdie@rpsys.net>
 279
 280 ---------------------------
 281
 282 What:   Multipath cached routing support in ipv4
 283 When:   in 2.6.23
 284 Why:    Code was merged, then submitter immediately disappeared leaving
 285         us with no maintainer and lots of bugs.  The code should not have
 286         been merged in the first place, and many aspects of it's
 287         implementation are blocking more critical core networking
 288         development.  It's marked EXPERIMENTAL and no distribution
 289         enables it because it cause obscure crashes due to unfixable bugs
 290         (interfaces don't return errors so memory allocation can't be
 291         handled, calling contexts of these interfaces make handling
 292         errors impossible too because they get called after we've
 293         totally commited to creating a route object, for example).
 294         This problem has existed for years and no forward progress
 295         has ever been made, and nobody steps up to try and salvage
 296         this code, so we're going to finally just get rid of it.
 297 Who:    David S. Miller <davem@davemloft.net>
 298
 299 ---------------------------
 300
 301 What:   read_dev_chars(), read_conf_data{,_lpm}() (s390 common I/O layer)
 302 When:   December 2007
 303 Why:    These functions are a leftover from 2.4 times. They have several
 304         problems:
 305         - Duplication of checks that are done in the device driver's
 306           interrupt handler
 307         - common I/O layer can't do device specific error recovery
 308         - device driver can't be notified for conditions happening during
 309           execution of the function
 310         Device drivers should issue the read device characteristics and read
 311         configuration data ccws and do the appropriate error handling
 312         themselves.
 313 Who:    Cornelia Huck <cornelia.huck@de.ibm.com>
 314
 315 ---------------------------
 316
 317 What:   i2c-ixp2000, i2c-ixp4xx and scx200_i2c drivers
 318 When:   September 2007
 319 Why:    Obsolete. The new i2c-gpio driver replaces all hardware-specific
 320         I2C-over-GPIO drivers.
 321 Who:    Jean Delvare <khali@linux-fr.org>
 322
 323 ---------------------------
 324
 325 What:  drivers depending on OSS_OBSOLETE
 326 When:  options in 2.6.23, code in 2.6.25
 327 Why:   obsolete OSS drivers
 328 Who:   Adrian Bunk <bunk@stusta.de>
 329
 330 ---------------------------
 331
 332 What: libata spindown skipping and warning
 333 When: Dec 2008
 334 Why:  Some halt(8) implementations synchronize caches for and spin
 335       down libata disks because libata didn't use to spin down disk on
 336       system halt (only synchronized caches).
 337       Spin down on system halt is now implemented.  sysfs node
 338       /sys/class/scsi_disk/h:c:i:l/manage_start_stop is present if
 339       spin down support is available.
 340       Because issuing spin down command to an already spun down disk
 341       makes some disks spin up just to spin down again, libata tracks
 342       device spindown status to skip the extra spindown command and
 343       warn about it.
 344       This is to give userspace tools the time to get updated and will
 345       be removed after userspace is reasonably updated.
 346 Who:  Tejun Heo <htejun@gmail.com>
 347
 348 ---------------------------
 349