kernel/linux.git/drivers/char/Kconfig, branch v7.2-rc1

char: applicom: remove low-quality, unused driver

2026-05-23T11:47:34+00:00

The applicom driver supports PCI Profibus cards from Applicom, later acquired by Molex. It has severe coding style issues and has attracted a number of bug and security fixes over the years, despite the fact that no one appears to be using it. It was broken from at least the beginning of Git history (Linux 2.6.12-rc2 in April 2005) until October 2008, when a fatal bug was fixed in commit bc20589bf1c6 ("applicom.c: fix apparently-broken code in do_ac_read()"). In the commit message, the author commented that no one they knew was able to test the change. Since then, there have been no commits that indicate the driver is being used. Later PCI and PCI-Express Applicom Profibus cards only officially support Windows [1], and even the PCI-Express cards have been discontinued [2]. Given all these factors, remove the driver to reduce future maintenance workload. [1] https://www.sarcitalia.it/file_upload/prodotti//PCIE1500S7_PFB_987651-3769_0876250001505823933.pdf [2] https://us.rs-online.com/product/molex-woodhead-brad/112011-5026/70631928/ Signed-off-by: Ethan Nelson-Moore Acked-by: David Woodhouse Acked-by: Arnd Bergmann Link: https://patch.msgid.link/20260503035824.24078-1-enelsonmoore@gmail.com Signed-off-by: Greg Kroah-Hartman

char: dtlk: remove driver for ISA speech synthesizer card

2026-05-23T11:47:34+00:00

The dtlk driver supports the RC Systems DoubleTalk PC ISA speech synthesizer card. It has severe coding style issues and has only received tree-wide fixes and drive-by cleanups in the entire Git history (since Linux 2.6.12-rc2). The same hardware is supported by drivers/accessibility/speakup for screen reader use, but that implementation does not share any code with this driver. Given all of these factors, it is likely the driver is entirely unused. Remove it to reduce future maintenance workload. Note: The removed maintainer is already listed in CREDITS. Signed-off-by: Ethan Nelson-Moore Link: https://patch.msgid.link/20260502043341.34324-1-enelsonmoore@gmail.com Signed-off-by: Greg Kroah-Hartman

char/mwave: drop it

2025-12-29T10:53:38+00:00

When I tried to clean up the driver a bit, Arnd noted: > According to thinkwiki.de, the 3780i modem was only used in a > couple of Thinkpad models that are now over 25 years old, using > Pentium II processors, and they all have a physical RS232 port > that can be used to connect an external modem instead. > > Maybe we can just retire this driver? So instead of the clean up, drop the driver altogether. Signed-off-by: Jiri Slaby (SUSE) Suggested-by: Arnd Bergmann Link: https://lore.kernel.org/all/b8834e5d-fdde-4b1a-8757-288dddc507a9@app.fastmail.com/ Link: https://patch.msgid.link/20251124103952.995229-1-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman

drivers: char: SONYPI depends on HAS_IOPORT

2025-06-24T15:44:19+00:00

It already depends on X86_32, but that's also set for ARCH=um. Recent changes made UML no longer have IO port access since it's not needed, but this driver uses it. Build it only for HAS_IOPORT. This is pretty much the same as depending on X86, but on the off-chance that HAS_IOPORT will ever be optional on x86 HAS_IOPORT is the real prerequisite. Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202506060742.XR3HcxWA-lkp@intel.com/ Signed-off-by: Johannes Berg Acked-by: Randy Dunlap Tested-by: Randy Dunlap Acked-by: Arnd Bergmann Link: https://lore.kernel.org/r/20250606071255.7722-2-johannes@sipsolutions.net Signed-off-by: Greg Kroah-Hartman

char: tlclk: Fix correct sysfs directory path for tlclk

2025-05-21T12:51:29+00:00

The tlckl driver does not create a platform device anymore. It was recently changed to use a faux device instead. Therefore the sysfs path has changed from /sys/devices/platform/telco_clock to /sys/devices/faux/telco_clock. Fixes: 72239a78f9f5 ("tlclk: convert to use faux_device") Signed-off-by: Roxana Nicolescu Link: https://lore.kernel.org/r/20250501200457.18506-1-nicolescu.roxana@protonmail.com Signed-off-by: Greg Kroah-Hartman

ACPI: EC: make EC support compile-time conditional

2024-10-24T15:47:15+00:00

The embedded controller code is mainly used on x86 laptops and cannot work without PC style I/O port access. Make this a user-visible configuration option that is default enabled on x86 but otherwise disabled, and that can never be enabled unless CONFIG_HAS_IOPORT is also available. The empty stubs in internal.h help ignore the EC code in configurations that don't support it. In order to see those stubs, the sbshc code also has to include this header and drop duplicate declarations. All the direct callers of ec_read/ec_write already had an x86 dependency and now also need to depend on APCI_EC. Signed-off-by: Arnd Bergmann Acked-by: Guenter Roeck Acked-by: Hans de Goede Link: https://patch.msgid.link/20241011061948.3211423-1-arnd@kernel.org [ rjw: Subject edits ] Signed-off-by: Rafael J. Wysocki

arch: Remove Itanium (IA-64) architecture

2023-09-11T08:13:17+00:00

The Itanium architecture is obsolete, and an informal survey [0] reveals that any residual use of Itanium hardware in production is mostly HP-UX or OpenVMS based. The use of Linux on Itanium appears to be limited to enthusiasts that occasionally boot a fresh Linux kernel to see whether things are still working as intended, and perhaps to churn out some distro packages that are rarely used in practice. None of the original companies behind Itanium still produce or support any hardware or software for the architecture, and it is listed as 'Orphaned' in the MAINTAINERS file, as apparently, none of the engineers that contributed on behalf of those companies (nor anyone else, for that matter) have been willing to support or maintain the architecture upstream or even be responsible for applying the odd fix. The Intel firmware team removed all IA-64 support from the Tianocore/EDK2 reference implementation of EFI in 2018. (Itanium is the original architecture for which EFI was developed, and the way Linux supports it deviates significantly from other architectures.) Some distros, such as Debian and Gentoo, still maintain [unofficial] ia64 ports, but many have dropped support years ago. While the argument is being made [1] that there is a 'for the common good' angle to being able to build and run existing projects such as the Grid Community Toolkit [2] on Itanium for interoperability testing, the fact remains that none of those projects are known to be deployed on Linux/ia64, and very few people actually have access to such a system in the first place. Even if there were ways imaginable in which Linux/ia64 could be put to good use today, what matters is whether anyone is actually doing that, and this does not appear to be the case. There are no emulators widely available, and so boot testing Itanium is generally infeasible for ordinary contributors. GCC still supports IA-64 but its compile farm [3] no longer has any IA-64 machines. GLIBC would like to get rid of IA-64 [4] too because it would permit some overdue code cleanups. In summary, the benefits to the ecosystem of having IA-64 be part of it are mostly theoretical, whereas the maintenance overhead of keeping it supported is real. So let's rip off the band aid, and remove the IA-64 arch code entirely. This follows the timeline proposed by the Debian/ia64 maintainer [5], which removes support in a controlled manner, leaving IA-64 in a known good state in the most recent LTS release. Other projects will follow once the kernel support is removed. [0] https://lore.kernel.org/all/CAMj1kXFCMh_578jniKpUtx_j8ByHnt=s7S+yQ+vGbKt9ud7+kQ@mail.gmail.com/ [1] https://lore.kernel.org/all/0075883c-7c51-00f5-2c2d-5119c1820410@web.de/ [2] https://gridcf.org/gct-docs/latest/index.html [3] https://cfarm.tetaneutral.net/machines/list/ [4] https://lore.kernel.org/all/87bkiilpc4.fsf@mid.deneb.enyo.de/ [5] https://lore.kernel.org/all/ff58a3e76e5102c94bb5946d99187b358def688a.camel@physik.fu-berlin.de/ Acked-by: Tony Luck Signed-off-by: Ard Biesheuvel

char: add HAS_IOPORT dependencies

2023-05-31T18:17:29+00:00

In a future patch HAS_IOPORT=n will result in inb()/outb() and friends not being declared. We thus need to add HAS_IOPORT as dependency for those drivers using them. Co-developed-by: Arnd Bergmann Signed-off-by: Arnd Bergmann Signed-off-by: Niklas Schnelle Link: https://lore.kernel.org/r/20230522105049.1467313-4-schnelle@linux.ibm.com Signed-off-by: Greg Kroah-Hartman

char: pcmcia: remove all the drivers

2023-03-09T16:30:27+00:00

These char PCMCIA drivers are buggy[1] and receive only minimal care. It was concluded[2], that we should try to remove most pcmcia drivers completely. Let's start with these char broken one. Note that I also removed a UAPI header: include/uapi/linux/cm4000_cs.h. I found only coccinelle tests mentioning some ioctl constants from that file. But they are not actually used. Anyway, should someone complain, we may reintroduce the header (or its parts). [1] https://lore.kernel.org/all/f41c2765-80e0-48bc-b1e4-8cfd3230fd4a@www.fastmail.com/ [2] https://lore.kernel.org/all/c5b39544-a4fb-4796-a046-0b9be9853787@app.fastmail.com/ Signed-off-by: Jiri Slaby (SUSE) Cc: "Hyunwoo Kim" Cc: Harald Welte Cc: Lubomir Rintel Cc: Arnd Bergmann Cc: Greg Kroah-Hartman Acked-by: Dominik Brodowski Reviewed-by: Arnd Bergmann Link: https://lore.kernel.org/r/20230222092302.6348-2-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman

random: use random.trust_{bootloader,cpu} command line option only

2022-11-18T01:18:10+00:00

It's very unusual to have both a command line option and a compile time option, and apparently that's confusing to people. Also, basically everybody enables the compile time option now, which means people who want to disable this wind up having to use the command line option to ensure that anyway. So just reduce the number of moving pieces and nix the compile time option in favor of the more versatile command line option. Signed-off-by: Jason A. Donenfeld