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.
7 ---------------------------
9 What: /sys/devices/.../power/state
10 dev->power.power_state
11 dpm_runtime_{suspend,resume)()
13 Why: Broken design for runtime control over driver power states, confusing
14 driver-internal runtime power management with: mechanisms to support
15 system-wide sleep state transitions; event codes that distinguish
16 different phases of swsusp "sleep" transitions; and userspace policy
17 inputs. This framework was never widely used, and most attempts to
18 use it were broken. Drivers should instead be exposing domain-specific
19 interfaces either to kernel or to userspace.
20 Who: Pavel Machek <pavel@suse.cz>
22 ---------------------------
24 What: RAW driver (CONFIG_RAW_DRIVER)
26 Why: declared obsolete since kernel 2.6.3
27 O_DIRECT can be used instead
28 Who: Adrian Bunk <bunk@stusta.de>
30 ---------------------------
32 What: raw1394: requests of type RAW1394_REQ_ISO_SEND, RAW1394_REQ_ISO_LISTEN
34 Why: Deprecated in favour of the more efficient and robust rawiso interface.
35 Affected are applications which use the deprecated part of libraw1394
36 (raw1394_iso_write, raw1394_start_iso_write, raw1394_start_iso_rcv,
37 raw1394_stop_iso_rcv) or bypass libraw1394.
38 Who: Dan Dennedy <dan@dennedy.org>, Stefan Richter <stefanr@s5r6.in-berlin.de>
40 ---------------------------
42 What: dv1394 driver (CONFIG_IEEE1394_DV1394)
44 Why: Replaced by raw1394 + userspace libraries, notably libiec61883. This
45 shift of application support has been indicated on www.linux1394.org
46 and developers' mailinglists for quite some time. Major applications
47 have been converted, with the exception of ffmpeg and hence xine.
48 Piped output of dvgrab2 is a partial equivalent to dv1394.
49 Who: Dan Dennedy <dan@dennedy.org>, Stefan Richter <stefanr@s5r6.in-berlin.de>
51 ---------------------------
53 What: ieee1394's *_oui sysfs attributes (CONFIG_IEEE1394_OUI_DB)
55 Files: drivers/ieee1394/: oui.db, oui2c.sh
56 Why: big size, little value
57 Who: Stefan Richter <stefanr@s5r6.in-berlin.de>
59 ---------------------------
61 What: Video4Linux API 1 ioctls and video_decoder.h from Video devices.
63 Why: V4L1 AP1 was replaced by V4L2 API. during migration from 2.4 to 2.6
64 series. The old API have lots of drawbacks and don't provide enough
65 means to work with all video and audio standards. The newer API is
66 already available on the main drivers and should be used instead.
67 Newer drivers should use v4l_compat_translate_ioctl function to handle
68 old calls, replacing to newer ones.
69 Decoder iocts are using internally to allow video drivers to
70 communicate with video decoders. This should also be improved to allow
71 V4L2 calls being translated into compatible internal ioctls.
72 Who: Mauro Carvalho Chehab <mchehab@brturbo.com.br>
74 ---------------------------
76 What: PCMCIA control ioctl (needed for pcmcia-cs [cardmgr, cardctl])
78 Files: drivers/pcmcia/: pcmcia_ioctl.c
79 Why: With the 16-bit PCMCIA subsystem now behaving (almost) like a
80 normal hotpluggable bus, and with it using the default kernel
81 infrastructure (hotplug, driver core, sysfs) keeping the PCMCIA
82 control ioctl needed by cardmgr and cardctl from pcmcia-cs is
83 unnecessary, and makes further cleanups and integration of the
84 PCMCIA subsystem into the Linux kernel device driver model more
85 difficult. The features provided by cardmgr and cardctl are either
86 handled by the kernel itself now or are available in the new
87 pcmciautils package available at
88 http://kernel.org/pub/linux/utils/kernel/pcmcia/
89 Who: Dominik Brodowski <linux@brodo.de>
91 ---------------------------
93 What: remove EXPORT_SYMBOL(kernel_thread)
95 Files: arch/*/kernel/*_ksyms.c
96 Why: kernel_thread is a low-level implementation detail. Drivers should
97 use the <linux/kthread.h> API instead which shields them from
98 implementation details and provides a higherlevel interface that
99 prevents bugs and code duplication
100 Who: Christoph Hellwig <hch@lst.de>
102 ---------------------------
104 What: CONFIG_FORCED_INLINING
106 Why: Config option is there to see if gcc is good enough. (in january
107 2006). If it is, the behavior should just be the default. If it's not,
108 the option should just go away entirely.
109 Who: Arjan van de Ven
111 ---------------------------
113 What: eepro100 network driver
115 Why: replaced by the e100 driver
116 Who: Adrian Bunk <bunk@stusta.de>
118 ---------------------------
120 What: drivers depending on OSS_OBSOLETE_DRIVER
121 When: options in 2.6.20, code in 2.6.22
122 Why: OSS drivers with ALSA replacements
123 Who: Adrian Bunk <bunk@stusta.de>
125 ---------------------------
127 What: pci_module_init(driver)
129 Why: Is replaced by pci_register_driver(pci_driver).
130 Who: Richard Knutsson <ricknu-0@student.ltu.se> and Greg Kroah-Hartman <gregkh@suse.de>
132 ---------------------------
134 What: Usage of invalid timevals in setitimer
136 Why: POSIX requires to validate timevals in the setitimer call. This
137 was never done by Linux. The invalid (e.g. negative timevals) were
138 silently converted to more or less random timeouts and intervals.
139 Until the removal a per boot limited number of warnings is printed
140 and the timevals are sanitized.
142 Who: Thomas Gleixner <tglx@linutronix.de>
144 ---------------------------
146 What: Unused EXPORT_SYMBOL/EXPORT_SYMBOL_GPL exports
147 (temporary transition config option provided until then)
148 The transition config option will also be removed at the same time.
150 Why: Unused symbols are both increasing the size of the kernel binary
151 and are often a sign of "wrong API"
152 Who: Arjan van de Ven <arjan@linux.intel.com>
154 ---------------------------
156 What: mount/umount uevents
158 Why: These events are not correct, and do not properly let userspace know
159 when a file system has been mounted or unmounted. Userspace should
160 poll the /proc/mounts file instead to detect this properly.
161 Who: Greg Kroah-Hartman <gregkh@suse.de>
163 ---------------------------
165 What: USB driver API moves to EXPORT_SYMBOL_GPL
167 Files: include/linux/usb.h, drivers/usb/core/driver.c
168 Why: The USB subsystem has changed a lot over time, and it has been
169 possible to create userspace USB drivers using usbfs/libusb/gadgetfs
170 that operate as fast as the USB bus allows. Because of this, the USB
171 subsystem will not be allowing closed source kernel drivers to
172 register with it, after this grace period is over. If anyone needs
173 any help in converting their closed source drivers over to use the
174 userspace filesystems, please contact the
175 linux-usb-devel@lists.sourceforge.net mailing list, and the developers
176 there will be glad to help you out.
177 Who: Greg Kroah-Hartman <gregkh@suse.de>
179 ---------------------------
181 What: find_trylock_page
183 Why: The interface no longer has any callers left in the kernel. It
184 is an odd interface (compared with other find_*_page functions), in
185 that it does not take a refcount to the page, only the page lock.
186 It should be replaced with find_get_page or find_lock_page if possible.
187 This feature removal can be reevaluated if users of the interface
188 cannot cleanly use something else.
189 Who: Nick Piggin <npiggin@suse.de>
191 ---------------------------
193 What: Interrupt only SA_* flags
195 Why: The interrupt related SA_* flags are replaced by IRQF_* to move them
196 out of the signal namespace.
198 Who: Thomas Gleixner <tglx@linutronix.de>
200 ---------------------------
202 What: PHYSDEVPATH, PHYSDEVBUS, PHYSDEVDRIVER in the uevent environment
204 Why: The stacking of class devices makes these values misleading and
206 Class devices should not carry any of these properties, and bus
207 devices have SUBSYTEM and DRIVER as a replacement.
208 Who: Kay Sievers <kay.sievers@suse.de>
210 ---------------------------
214 Why: i2c-isa is a non-sense and doesn't fit in the device driver
215 model. Drivers relying on it are better implemented as platform
217 Who: Jean Delvare <khali@linux-fr.org>
219 ---------------------------
221 What: i2c_adapter.dev
224 Why: Superfluous, given i2c_adapter.class_dev:
225 * The "dev" was a stand-in for the physical device node that legacy
226 drivers would not have; but now it's almost always present. Any
227 remaining legacy drivers must upgrade (they now trigger warnings).
228 * The "list" duplicates class device children.
229 The delay in removing this is so upgraded lm_sensors and libsensors
230 can get deployed. (Removal causes minor changes in the sysfs layout,
231 notably the location of the adapter type name and parenting the i2c
232 client hardware directly from their controller.)
233 Who: Jean Delvare <khali@linux-fr.org>,
234 David Brownell <dbrownell@users.sourceforge.net>
236 ---------------------------
238 What: IPv4 only connection tracking/NAT/helpers
240 Why: The new layer 3 independant connection tracking replaces the old
241 IPv4 only version. After some stabilization of the new code the
242 old one will be removed.
243 Who: Patrick McHardy <kaber@trash.net>
245 ---------------------------
247 What: ACPI hooks (X86_SPEEDSTEP_CENTRINO_ACPI) in speedstep-centrino driver
249 Why: Speedstep-centrino driver with ACPI hooks and acpi-cpufreq driver are
250 functionally very much similar. They talk to ACPI in same way. Only
251 difference between them is the way they do frequency transitions.
252 One uses MSRs and the other one uses IO ports. Functionaliy of
253 speedstep_centrino with ACPI hooks is now merged into acpi-cpufreq.
254 That means one common driver will support all Intel Enhanced Speedstep
255 capable CPUs. That means less confusion over name of
256 speedstep-centrino driver (with that driver supposed to be used on
257 non-centrino platforms). That means less duplication of code and
258 less maintenance effort and no possibility of these two drivers
260 Current users of speedstep_centrino with ACPI hooks are requested to
261 switch over to acpi-cpufreq driver. speedstep-centrino will continue
262 to work using older non-ACPI static table based scheme even after this
265 Who: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
267 ---------------------------
269 What: ACPI hotkey driver (CONFIG_ACPI_HOTKEY)
271 Why: hotkey.c was an attempt to consolidate multiple drivers that use
272 ACPI to implement hotkeys. However, hotkeys are not documented
273 in the ACPI specification, so the drivers used undocumented
274 vendor-specific hooks and turned out to be more different than
277 Further, the keys and the features supplied by each platform
278 are different, so there will always be a need for
279 platform-specific drivers.
281 So the new plan is to delete hotkey.c and instead, work on the
282 platform specific drivers to try to make them look the same
283 to the user when they supply the same features.
285 hotkey.c has always depended on CONFIG_EXPERIMENTAL
287 Who: Len Brown <len.brown@intel.com>
289 ---------------------------
291 What: /sys/firmware/acpi/namespace
293 Why: The ACPI namespace is effectively the symbol list for
294 the BIOS. The device names are completely arbitrary
295 and have no place being exposed to user-space.
297 For those interested in the BIOS ACPI namespace,
298 the BIOS can be extracted and disassembled with acpidump
299 and iasl as documented in the pmtools package here:
300 http://ftp.kernel.org/pub/linux/kernel/people/lenb/acpi/utils
302 Who: Len Brown <len.brown@intel.com>
304 ---------------------------
306 What: /proc/acpi/button
308 Why: /proc/acpi/button has been replaced by events to the input layer
310 Who: Len Brown <len.brown@intel.com>
312 ---------------------------
314 What: JFFS (version 1)
316 Why: Unmaintained for years, superceded by JFFS2 for years.
317 Who: Jeff Garzik <jeff@garzik.org>
319 ---------------------------