Commit Graph

8605 Commits

Author SHA1 Message Date
Tony Lindgren
04c7f60ca4 serial: core: Fix serial core port id, including multiport devices
We want to fix the serial core port DEVNAME to use a port id of the
hardware specific controller port instance instead of the port->line.

For example, the 8250 driver sets up a number of serial8250 ports
initially that can be inherited by the hardware specific driver. At that
the port->line no longer decribes the port's relation to the serial core
controller instance.

Let's fix the issue by assigning port->port_id for each serial core
controller port instance.

Fixes: 7d695d8376 ("serial: core: Fix serial_base_match() after fixing controller port name")
Tested-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Dhruva Gole <d-gole@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20230811103648.2826-1-tony@atomide.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-11 21:19:22 +02:00
Jiri Slaby (SUSE)
3d9e6f556e serial: 8250: drop lockdep annotation from serial8250_clear_IER()
The port lock is not always held when calling serial8250_clear_IER().
When an oops is in progress, the lock is tried to be taken and when it
is not, a warning is issued:
 WARNING: CPU: 0 PID: 1 at drivers/tty/serial/8250/8250_port.c:707 	+0x57/0x60
 Modules linked in:
 CPU: 0 PID: 1 Comm: init Not tainted 6.5.0-rc5-1.g225bfb7-default+ #774 00f1be860db663ed29479b8255d3b01ab1135bd3
 Hardware name: QEMU Standard PC ...
 RIP: 0010:serial8250_clear_IER+0x57/0x60
...
 Call Trace:
  <TASK>
  serial8250_console_write+0x9e/0x4b0
  console_flush_all+0x217/0x5f0
...

Therefore, remove the annotation as it doesn't hold for all invocations.

The other option would be to make the lockdep test conditional on
'oops_in_progress' or pass 'locked' from serial8250_console_write(). I
don't think, that is worth it.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Reported-by: Vlastimil Babka <vbabka@suse.cz>
Cc: John Ogness <john.ogness@linutronix.de>
Fixes: d0b309a5d3 (serial: 8250: synchronize and annotate UART_IER access)
Link: https://lore.kernel.org/r/20230811064340.13400-1-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-11 21:19:18 +02:00
Yi Yang
3c4f8333b5 tty: n_gsm: fix the UAF caused by race condition in gsm_cleanup_mux
In commit 9b9c8195f3 ("tty: n_gsm: fix UAF in gsm_cleanup_mux"), the UAF
problem is not completely fixed. There is a race condition in
gsm_cleanup_mux(), which caused this UAF.

The UAF problem is triggered by the following race:
task[5046]                     task[5054]
-----------------------        -----------------------
gsm_cleanup_mux();
dlci = gsm->dlci[0];
mutex_lock(&gsm->mutex);
                               gsm_cleanup_mux();
			       dlci = gsm->dlci[0]; //Didn't take the lock
gsm_dlci_release(gsm->dlci[i]);
gsm->dlci[i] = NULL;
mutex_unlock(&gsm->mutex);
                               mutex_lock(&gsm->mutex);
			       dlci->dead = true; //UAF

Fix it by assigning values after mutex_lock().

Link: https://syzkaller.appspot.com/text?tag=CrashReport&x=176188b5a80000
Cc: stable <stable@kernel.org>
Fixes: 9b9c8195f3 ("tty: n_gsm: fix UAF in gsm_cleanup_mux")
Fixes: aa371e96f0 ("tty: n_gsm: fix restart handling via CLD command")
Signed-off-by: Yi Yang <yiyang13@huawei.com>
Co-developed-by: Qiumiao Zhang <zhangqiumiao1@huawei.com>
Signed-off-by: Qiumiao Zhang <zhangqiumiao1@huawei.com>
Link: https://lore.kernel.org/r/20230811031121.153237-1-yiyang13@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-11 21:17:02 +02:00
Tony Lindgren
a4a79e03ba serial: core: Revert port_id use
Guenter reports boot issues with duplicate sysfs entries for multiport
drivers. Let's go back to using port->line for now to fix the regression.

With this change, the serial core port device names are not correct for the
hardware specific 8250 single port drivers, but that's a cosmetic issue for
now.

Fixes: d962de6ae5 ("serial: core: Fix serial core port id to not use port->line")
Reported-by: Guenter Roeck <groeck7@gmail.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20230806062052.47737-1-tony@atomide.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-09 14:12:43 +02:00
Günther Noack
3f29d9ee32 TIOCSTI: Document CAP_SYS_ADMIN behaviour in Kconfig
Clarifies that the LEGACY_TIOCSTI setting is safe to turn off even
when running BRLTTY, as it was introduced in commit 690c8b804a
("TIOCSTI: always enable for CAP_SYS_ADMIN").

Signed-off-by: Günther Noack <gnoack3000@gmail.com>
Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Link: https://lore.kernel.org/r/20230808201115.23993-1-gnoack3000@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-09 14:12:39 +02:00
Tony Lindgren
dfe2aeb226 serial: 8250: Fix oops for port->pm on uart_change_pm()
Unloading a hardware specific 8250 driver can produce error "Unable to
handle kernel paging request at virtual address" about ten seconds after
unloading the driver. This happens on uart_hangup() calling
uart_change_pm().

Turns out commit 04e82793f0 ("serial: 8250: Reinit port->pm on port
specific driver unbind") was only a partial fix. If the hardware specific
driver has initialized port->pm function, we need to clear port->pm too.
Just reinitializing port->ops does not do this. Otherwise serial8250_pm()
will call port->pm() instead of serial8250_do_pm().

Fixes: 04e82793f0 ("serial: 8250: Reinit port->pm on port specific driver unbind")
Signed-off-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20230804131553.52927-1-tony@atomide.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-04 17:14:38 +02:00
Tony Lindgren
bbb4abb1bc serial: 8250: Reinit port_id when adding back serial8250_isa_devs
After fixing the serial core port device to use port->port_id instead of
port->line, unloading a hardware specific 8250 port driver started
producing an error for "sysfs: cannot create duplicate filename".

This is happening as we are wrongly initializing port->port_id to zero
when adding back serial8250_isa_devs instances, and the serial8250:0.0
sysfs entry may already exist. For serial8250 devices, we typically have
multiple devices mapped to a single driver instance. For the
serial8250_isa_devs instances, the port->port_id is the same as port->line.

Let's fix the issue by re-initializing port_id when adding back the
serial8250_isa_devs instances in serial8250_unregister_port().

Fixes: d962de6ae5 ("serial: core: Fix serial core port id to not use port->line")
Signed-off-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20230804123546.25293-1-tony@atomide.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-04 15:11:59 +02:00
Tony Lindgren
6be1a8d50b serial: core: Fix kmemleak issue for serial core device remove
Kmemleak reports issues for serial8250 ports after the hardware specific
driver takes over on boot as noted by Tomi.

The kerneldoc for device_initialize() says we must call device_put()
after calling device_initialize(). We are calling device_put() on the
error path, but are missing it from the device remove path. This causes
release() to never get called for the devices on remove.

Let's add the missing put_device() calls for both serial ctrl and
port devices.

Fixes: 84a9582fd2 ("serial: core: Start managing serial controllers to enable runtime PM")
Reported-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Tested-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Link: https://lore.kernel.org/r/20230804090909.51529-1-tony@atomide.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-04 15:11:36 +02:00
Tony Lindgren
7d695d8376 serial: core: Fix serial_base_match() after fixing controller port name
While fixing DEVNAME to be more usable, I broke serial_base_match() as the
ctrl and port prefix for device names seemed unnecessary.

The prefixes are still needed by serial_base_match() to probe the serial
base controller port, and serial tx is now broken.

Let's fix the issue by checking against dev->type and drv->name instead
of the prefixes that are no longer in the DEVNAME.

Fixes: 1ef2c2df11 ("serial: core: Fix serial core controller port name to show controller id")
Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202308021529.35b3ad6c-oliver.sang@intel.com
Signed-off-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20230803071034.25571-1-tony@atomide.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-03 09:48:56 +02:00
Tony Lindgren
1ef2c2df11 serial: core: Fix serial core controller port name to show controller id
We are missing the serial core controller id for the serial core port
name. Let's fix the issue for sane sysfs output, and to avoid issues
addressing serial ports later on.

And as we're now showing the controller id, the "ctrl" and "port" prefix
for the DEVNAME become useless, we can just drop them. Let's standardize on
DEVNAME:0 for controller name, where 0 is the controller id. And
DEVNAME:0.0 for port name, where 0.0 are the controller id and port id.

This makes the sysfs output nicer, on qemu for example:

$ ls /sys/bus/serial-base/devices
00:04:0         serial8250:0    serial8250:0.2
00:04:0.0       serial8250:0.1  serial8250:0.3

Fixes: 84a9582fd2 ("serial: core: Start managing serial controllers to enable runtime PM")
Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20230725054216.45696-4-tony@atomide.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-01 07:48:55 +02:00
Tony Lindgren
d962de6ae5 serial: core: Fix serial core port id to not use port->line
The serial core port id should be serial core controller specific port
instance, which is not always the port->line index.

For example, 8250 driver maps a number of legacy ports, and when a
hardware specific device driver takes over, we typically have one
driver instance for each port. Let's instead add port->port_id to
keep track serial ports mapped to each serial core controller instance.

Currently this is only a cosmetic issue for the serial core port device
names. The issue can be noticed looking at /sys/bus/serial-base/devices
for example though. Let's fix the issue to avoid port addressing issues
later on.

Fixes: 84a9582fd2 ("serial: core: Start managing serial controllers to enable runtime PM")
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20230725054216.45696-3-tony@atomide.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-01 07:48:55 +02:00
Sherry Sun
282069845a tty: serial: fsl_lpuart: Clear the error flags by writing 1 for lpuart32 platforms
Do not read the data register to clear the error flags for lpuart32
platforms, the additional read may cause the receive FIFO underflow
since the DMA has already read the data register.
Actually all lpuart32 platforms support write 1 to clear those error
bits, let's use this method to better clear the error flags.

Fixes: 42b68768e5 ("serial: fsl_lpuart: DMA support for 32-bit variant")
Cc: stable <stable@kernel.org>
Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Link: https://lore.kernel.org/r/20230801022304.24251-1-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-01 07:31:53 +02:00
Linus Torvalds
e6d34ced01 TTY/Serial fixes for 6.5-rc4
Here are some small TTY and serial driver fixes for 6.5-rc4 for some
 reported problems.  Included in here is:
   - TIOCSTI fix for braille readers
   - documentation fix for minor numbers
   - MAINTAINERS update for new serial files in -rc1
   - minor serial driver fixes for reported problems
 
 All of these have been in linux-next with no reported problems.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-6.5-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial fixes from Greg KH:
 "Here are some small TTY and serial driver fixes for 6.5-rc4 for some
  reported problems. Included in here is:

   - TIOCSTI fix for braille readers

   - documentation fix for minor numbers

   - MAINTAINERS update for new serial files in -rc1

   - minor serial driver fixes for reported problems

  All of these have been in linux-next with no reported problems"

* tag 'tty-6.5-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  serial: 8250_dw: Preserve original value of DLF register
  tty: serial: sh-sci: Fix sleeping in atomic context
  serial: sifive: Fix sifive_serial_console_setup() section
  Documentation: devices.txt: reconcile serial/ucc_uart minor numers
  MAINTAINERS: Update TTY layer for lists and recently added files
  tty: n_gsm: fix UAF in gsm_cleanup_mux
  TIOCSTI: always enable for CAP_SYS_ADMIN
2023-07-30 11:51:36 -07:00
Ruihong Luo
748c5ea8b8 serial: 8250_dw: Preserve original value of DLF register
Preserve the original value of the Divisor Latch Fraction (DLF) register.
When the DLF register is modified without preservation, it can disrupt
the baudrate settings established by firmware or bootloader, leading to
data corruption and the generation of unreadable or distorted characters.

Fixes: 701c5e73b2 ("serial: 8250_dw: add fractional divisor support")
Cc: stable <stable@kernel.org>
Signed-off-by: Ruihong Luo <colorsu1922@gmail.com>
Link: https://lore.kernel.org/stable/20230713004235.35904-1-colorsu1922%40gmail.com
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20230713004235.35904-1-colorsu1922@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-25 20:31:31 +02:00
Biju Das
57c984f6fe tty: serial: sh-sci: Fix sleeping in atomic context
Fix sleeping in atomic context warning as reported by the Smatch static
checker tool by replacing disable_irq->disable_irq_nosync.

Reported by: Dan Carpenter <dan.carpenter@linaro.org>

Fixes: 8749061be1 ("tty: serial: sh-sci: Add RZ/G2L SCIFA DMA tx support")
Cc: stable@kernel.org
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20230704154818.406913-1-biju.das.jz@bp.renesas.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-25 20:30:20 +02:00
Samuel Holland
9b8fef6345 serial: sifive: Fix sifive_serial_console_setup() section
This function is called indirectly from the platform driver probe
function. Even if the driver is built in, it may be probed after
free_initmem() due to deferral or unbinding/binding via sysfs.
Thus the function cannot be marked as __init.

Fixes: 45c054d081 ("tty: serial: add driver for the SiFive UART")
Cc: stable <stable@kernel.org>
Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Link: https://lore.kernel.org/r/20230624060159.3401369-1-samuel.holland@sifive.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-25 20:30:02 +02:00
Randy Dunlap
e29c3f81eb Documentation: devices.txt: reconcile serial/ucc_uart minor numers
Reconcile devices.txt with serial/ucc_uart.c regarding device number
assignments. ucc_uart.c supports 4 ports and uses minor devnums
46-49, so update devices.txt with that info.
Then update ucc_uart.c's reference to the location of the devices.txt
list in the kernel source tree.

Fixes: d7584ed2b9 ("[POWERPC] qe-uart: add support for Freescale QUICCEngine UART")
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Timur Tabi <timur@kernel.org>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: linux-serial@vger.kernel.org
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Link: https://lore.kernel.org/r/20230724063341.28198-1-rdunlap@infradead.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-25 19:29:23 +02:00
Chaoyuan Peng
9b9c8195f3 tty: n_gsm: fix UAF in gsm_cleanup_mux
In gsm_cleanup_mux() the 'gsm->dlci' pointer was not cleaned properly,
leaving it a dangling pointer after gsm_dlci_release.
This leads to use-after-free where 'gsm->dlci[0]' are freed and accessed
by the subsequent gsm_cleanup_mux().

Such is the case in the following call trace:

 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 print_address_description+0x63/0x3b0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:434 [inline]
 kasan_report+0x16b/0x1c0 mm/kasan/report.c:451
 gsm_cleanup_mux+0x76a/0x850 drivers/tty/n_gsm.c:2397
 gsm_config drivers/tty/n_gsm.c:2653 [inline]
 gsmld_ioctl+0xaae/0x15b0 drivers/tty/n_gsm.c:2986
 tty_ioctl+0x8ff/0xc50 drivers/tty/tty_io.c:2816
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
 </TASK>

Allocated by task 3501:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 ____kasan_kmalloc+0xba/0xf0 mm/kasan/common.c:513
 kasan_kmalloc include/linux/kasan.h:264 [inline]
 kmem_cache_alloc_trace+0x143/0x290 mm/slub.c:3247
 kmalloc include/linux/slab.h:591 [inline]
 kzalloc include/linux/slab.h:721 [inline]
 gsm_dlci_alloc+0x53/0x3a0 drivers/tty/n_gsm.c:1932
 gsm_activate_mux+0x1c/0x330 drivers/tty/n_gsm.c:2438
 gsm_config drivers/tty/n_gsm.c:2677 [inline]
 gsmld_ioctl+0xd46/0x15b0 drivers/tty/n_gsm.c:2986
 tty_ioctl+0x8ff/0xc50 drivers/tty/tty_io.c:2816
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb

Freed by task 3501:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track+0x4b/0x80 mm/kasan/common.c:46
 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360
 ____kasan_slab_free+0xd8/0x120 mm/kasan/common.c:366
 kasan_slab_free include/linux/kasan.h:230 [inline]
 slab_free_hook mm/slub.c:1705 [inline]
 slab_free_freelist_hook+0xdd/0x160 mm/slub.c:1731
 slab_free mm/slub.c:3499 [inline]
 kfree+0xf1/0x270 mm/slub.c:4559
 dlci_put drivers/tty/n_gsm.c:1988 [inline]
 gsm_dlci_release drivers/tty/n_gsm.c:2021 [inline]
 gsm_cleanup_mux+0x574/0x850 drivers/tty/n_gsm.c:2415
 gsm_config drivers/tty/n_gsm.c:2653 [inline]
 gsmld_ioctl+0xaae/0x15b0 drivers/tty/n_gsm.c:2986
 tty_ioctl+0x8ff/0xc50 drivers/tty/tty_io.c:2816
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb

Fixes: aa371e96f0 ("tty: n_gsm: fix restart handling via CLD command")
Signed-off-by: Chaoyuan Peng <hedonistsmith@gmail.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-25 19:07:25 +02:00
Johan Hovold
4dd8752a14 serial: qcom-geni: drop bogus runtime pm state update
The runtime PM state should not be changed by drivers that do not
implement runtime PM even if it happens to work around a bug in PM core.

With the wake irq arming now fixed, drop the bogus runtime PM state
update which left the device in active state (and could potentially
prevent a parent device from suspending).

Fixes: f3974413cf ("tty: serial: qcom_geni_serial: Wakeup IRQ cleanup")
Cc: 5.6+ <stable@vger.kernel.org> # 5.6+
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2023-07-24 09:51:51 +02:00
Samuel Thibault
690c8b804a TIOCSTI: always enable for CAP_SYS_ADMIN
83efeeeb3d ("tty: Allow TIOCSTI to be disabled") broke BRLTTY's
ability to simulate keypresses on the console, thus effectively breaking
braille keyboards of blind users.

This restores the TIOCSTI feature for CAP_SYS_ADMIN processes, which
BRLTTY is, thus fixing braille keyboards without re-opening the security
issue.

Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Acked-by: Kees Cook <keescook@chromium.org>
Fixes: 83efeeeb3d ("tty: Allow TIOCSTI to be disabled")
Cc: stable@vger.kernel.org
Reported-by: Nicolas Pitre <nico@fluxnic.net>
Link: https://lore.kernel.org/r/20230710002645.v565c7xq5iddruse@begin
Acked-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-20 19:21:16 +02:00
Linus Torvalds
868a9fd948 TTY/Serial driver updates for 6.5-rc1.
Here is the big set of tty/serial driver updates for 6.5-rc1.
 
 Included in here are:
   - tty_audit code cleanups from Jiri
   - more 8250 cleanups from Ilpo
   - samsung_tty driver bugfixes
   - 8250 lock port updates
   - usual fsl_lpuart driver updates and fixes
   - other small serial driver fixes and updates, full details in the
     shortlog.
 
 All of these have been in linux-next for a while with no reported
 issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-6.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial driver updates from Greg KH:
 "Here is the big set of tty/serial driver updates for 6.5-rc1.

  Included in here are:

   - tty_audit code cleanups from Jiri

   - more 8250 cleanups from Ilpo

   - samsung_tty driver bugfixes

   - 8250 lock port updates

   - usual fsl_lpuart driver updates and fixes

   - other small serial driver fixes and updates, full details in the
     shortlog

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'tty-6.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (58 commits)
  tty_audit: make data of tty_audit_log() const
  tty_audit: make tty pointers in exposed functions const
  tty_audit: make icanon a bool
  tty_audit: invert the condition in tty_audit_log()
  tty_audit: use kzalloc() in tty_audit_buf_alloc()
  tty_audit: use TASK_COMM_LEN for task comm
  Revert "8250: add support for ASIX devices with a FIFO bug"
  serial: atmel: don't enable IRQs prematurely
  tty: serial: Add Nuvoton ma35d1 serial driver support
  tty: serial: fsl_lpuart: add earlycon for imx8ulp platform
  tty: serial: imx: fix rs485 rx after tx
  selftests: tty: add selftest for tty timestamp updates
  tty: tty_io: update timestamps on all device nodes
  tty: fix hang on tty device with no_room set
  serial: core: fix -EPROBE_DEFER handling in init
  serial: 8250_omap: Use force_suspend and resume for system suspend
  tty: serial: samsung_tty: Use abs() to simplify some code
  tty: serial: samsung_tty: Fix a memory leak in s3c24xx_serial_getclk() when iterating clk
  tty: serial: samsung_tty: Fix a memory leak in s3c24xx_serial_getclk() in case of error
  serial: 8250: Apply FSL workarounds also without SERIAL_8250_CONSOLE
  ...
2023-07-03 13:14:58 -07:00
Linus Torvalds
fc75f21645 driver core changes for 6.5-rc1
Here are a small set of changes for 6.5-rc1 for some driver core
 changes.  Included in here are:
   - device property cleanups to make it easier to write "agnostic"
     drivers when regards to the firmware layer underneath them (DT vs.
     ACPI)
   - debugfs documentation updates
   - devres additions
   - sysfs documentation and changes to handle empty directory creation
     logic better
   - tiny kernfs optimizations
   - other tiny changes
 
 All of these have been in linux-next for a while with no reported
 problems.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-6.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here are a small set of changes for 6.5-rc1 for some driver core
  changes. Included in here are:

   - device property cleanups to make it easier to write "agnostic"
     drivers when regards to the firmware layer underneath them (DT vs.
     ACPI)

   - debugfs documentation updates

   - devres additions

   - sysfs documentation and changes to handle empty directory creation
     logic better

   - tiny kernfs optimizations

   - other tiny changes

  All of these have been in linux-next for a while with no reported
  problems"

* tag 'driver-core-6.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  sysfs: Skip empty folders creation
  sysfs: Improve readability by following the kernel coding style
  drivers: fwnode: fix fwnode_irq_get[_byname]()
  ata: ahci_platform: Make code agnostic to OF/ACPI
  device property: Implement device_is_compatible()
  ACPI: Move ACPI_DEVICE_CLASS() to mod_devicetable.h
  base/node: Use 'property' to identify an access parameter
  driver core: device.h: add some missing kerneldocs
  kernfs: fix missing kernfs_idr_lock to remove an ID from the IDR
  isa: Remove unnecessary checks
  MAINTAINERS: add entry for auxiliary bus
  debugfs: Correct the 'debugfs_create_str' docs
  serial: qcom_geni: Comment use of devm_krealloc rather than devm_krealloc_array
  iio: adc: Use devm_krealloc_array
  hwmon: pmbus: Use devm_krealloc_array
2023-07-03 12:56:23 -07:00
Linus Torvalds
04fc8904d5 Move the Arm architecture documentation under Documentation/arch/. This
brings some order to the documentation directory, declutters the top-level
 directory, and makes the documentation organization more closely match that
 of the source.
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Merge tag 'docs-arm-move' of git://git.lwn.net/linux

Pull arm documentation move from Jonathan Corbet:
 "Move the Arm architecture documentation under Documentation/arch/.

  This brings some order to the documentation directory, declutters the
  top-level directory, and makes the documentation organization more
  closely match that of the source"

* tag 'docs-arm-move' of git://git.lwn.net/linux:
  dt-bindings: Update Documentation/arm references
  docs: update some straggling Documentation/arm references
  crypto: update some Arm documentation references
  mips: update a reference to a moved Arm Document
  arm64: Update Documentation/arm references
  arm: update in-source documentation references
  arm: docs: Move Arm documentation to Documentation/arch/
2023-06-27 11:58:16 -07:00
Linus Torvalds
3eccc0c886 for-6.5/splice-2023-06-23
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Merge tag 'for-6.5/splice-2023-06-23' of git://git.kernel.dk/linux

Pull splice updates from Jens Axboe:
 "This kills off ITER_PIPE to avoid a race between truncate,
  iov_iter_revert() on the pipe and an as-yet incomplete DMA to a bio
  with unpinned/unref'ed pages from an O_DIRECT splice read. This causes
  memory corruption.

  Instead, we either use (a) filemap_splice_read(), which invokes the
  buffered file reading code and splices from the pagecache into the
  pipe; (b) copy_splice_read(), which bulk-allocates a buffer, reads
  into it and then pushes the filled pages into the pipe; or (c) handle
  it in filesystem-specific code.

  Summary:

   - Rename direct_splice_read() to copy_splice_read()

   - Simplify the calculations for the number of pages to be reclaimed
     in copy_splice_read()

   - Turn do_splice_to() into a helper, vfs_splice_read(), so that it
     can be used by overlayfs and coda to perform the checks on the
     lower fs

   - Make vfs_splice_read() jump to copy_splice_read() to handle
     direct-I/O and DAX

   - Provide shmem with its own splice_read to handle non-existent pages
     in the pagecache. We don't want a ->read_folio() as we don't want
     to populate holes, but filemap_get_pages() requires it

   - Provide overlayfs with its own splice_read to call down to a lower
     layer as overlayfs doesn't provide ->read_folio()

   - Provide coda with its own splice_read to call down to a lower layer
     as coda doesn't provide ->read_folio()

   - Direct ->splice_read to copy_splice_read() in tty, procfs, kernfs
     and random files as they just copy to the output buffer and don't
     splice pages

   - Provide wrappers for afs, ceph, ecryptfs, ext4, f2fs, nfs, ntfs3,
     ocfs2, orangefs, xfs and zonefs to do locking and/or revalidation

   - Make cifs use filemap_splice_read()

   - Replace pointers to generic_file_splice_read() with pointers to
     filemap_splice_read() as DIO and DAX are handled in the caller;
     filesystems can still provide their own alternate ->splice_read()
     op

   - Remove generic_file_splice_read()

   - Remove ITER_PIPE and its paraphernalia as generic_file_splice_read
     was the only user"

* tag 'for-6.5/splice-2023-06-23' of git://git.kernel.dk/linux: (31 commits)
  splice: kdoc for filemap_splice_read() and copy_splice_read()
  iov_iter: Kill ITER_PIPE
  splice: Remove generic_file_splice_read()
  splice: Use filemap_splice_read() instead of generic_file_splice_read()
  cifs: Use filemap_splice_read()
  trace: Convert trace/seq to use copy_splice_read()
  zonefs: Provide a splice-read wrapper
  xfs: Provide a splice-read wrapper
  orangefs: Provide a splice-read wrapper
  ocfs2: Provide a splice-read wrapper
  ntfs3: Provide a splice-read wrapper
  nfs: Provide a splice-read wrapper
  f2fs: Provide a splice-read wrapper
  ext4: Provide a splice-read wrapper
  ecryptfs: Provide a splice-read wrapper
  ceph: Provide a splice-read wrapper
  afs: Provide a splice-read wrapper
  9p: Add splice_read wrapper
  net: Make sock_splice_read() use copy_splice_read() by default
  tty, proc, kernfs, random: Use copy_splice_read()
  ...
2023-06-26 11:52:12 -07:00
Jiri Slaby
e534755c94 tty_audit: make data of tty_audit_log() const
'data' are only read (passed down to audit_log_n_hex()), so they can be
const -- the same what is expected in audit_log_n_hex(). Only a minor
cleanup to be consistent.

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20230621101611.10580-7-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-21 17:57:29 +02:00
Jiri Slaby
e64ed44bce tty_audit: make tty pointers in exposed functions const
Both tty_audit_add_data() and tty_audit_tiocsti() need only to read from
the tty struct, so make the tty parameters of them both const. This
aids the compiler a bit.

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20230621101611.10580-6-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-21 17:57:29 +02:00
Jiri Slaby
3e540a7bad tty_audit: make icanon a bool
Use bool for tty_audit_buf::icanon in favor of ugly bitfields. And get
rid of "!!" as that is completely unnecessary.

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20230621101611.10580-5-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-21 17:57:29 +02:00
Jiri Slaby
94f94810ef tty_audit: invert the condition in tty_audit_log()
If we cannot obtain an audit buffer in tty_audit_log(), simply return
from the function. Apart this is mostly preferred in the kernel, it
allows to merge the split audit string while still keeping it readable.

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20230621101611.10580-4-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-21 17:57:29 +02:00
Jiri Slaby
e1488513ab tty_audit: use kzalloc() in tty_audit_buf_alloc()
tty_audit_buf_alloc() manually erases most of the entries after
kmalloc(). So use kzalloc() and remove the manual sets to zero.

That way, we are sure that we do not omit anything.

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20230621101611.10580-3-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-21 17:57:29 +02:00
Jiri Slaby
777e456852 tty_audit: use TASK_COMM_LEN for task comm
This is the preferred way of declaring an array for get_task_comm().

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20230621101611.10580-2-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-21 17:57:29 +02:00
Jiaqing Zhao
a82d62f708 Revert "8250: add support for ASIX devices with a FIFO bug"
This reverts commit eb26dfe8aa.

Commit eb26dfe8aa ("8250: add support for ASIX devices with a FIFO
bug") merged on Jul 13, 2012 adds a quirk for PCI_VENDOR_ID_ASIX
(0x9710). But that ID is the same as PCI_VENDOR_ID_NETMOS defined in
1f8b061050c7 ("[PATCH] Netmos parallel/serial/combo support") merged
on Mar 28, 2005. In pci_serial_quirks array, the NetMos entry always
takes precedence over the ASIX entry even since it was initially
merged, code in that commit is always unreachable.

In my tests, adding the FIFO workaround to pci_netmos_init() makes no
difference, and the vendor driver also does not have such workaround.
Given that the code was never used for over a decade, it's safe to
revert it.

Also, the real PCI_VENDOR_ID_ASIX should be 0x125b, which is used on
their newer AX99100 PCIe serial controllers released on 2016. The FIFO
workaround should not be intended for these newer controllers, and it
was never implemented in vendor driver.

Fixes: eb26dfe8aa ("8250: add support for ASIX devices with a FIFO bug")
Cc: stable <stable@kernel.org>
Signed-off-by: Jiaqing Zhao <jiaqing.zhao@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20230619155743.827859-1-jiaqing.zhao@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-21 17:55:53 +02:00
Dan Carpenter
27a826837e serial: atmel: don't enable IRQs prematurely
The atmel_complete_tx_dma() function disables IRQs at the start
of the function by calling spin_lock_irqsave(&port->lock, flags);
There is no need to disable them a second time using the
spin_lock_irq() function and, in fact, doing so is a bug because
it will enable IRQs prematurely when we call spin_unlock_irq().

Just use spin_lock/unlock() instead without disabling or enabling
IRQs.

Fixes: 08f738be88 ("serial: at91: add tx dma support")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Acked-by: Richard Genoud <richard.genoud@gmail.com>
Link: https://lore.kernel.org/r/cb7c39a9-c004-4673-92e1-be4e34b85368@moroto.mountain
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-21 17:54:33 +02:00
Jacky Huang
930cbf92db tty: serial: Add Nuvoton ma35d1 serial driver support
This adds UART and console driver for Nuvoton ma35d1 Soc.
It supports full-duplex communication, FIFO control, and
hardware flow control.
Command line set "console=ttyNVT0,115200", NVT means
Nuvoton MA35 UART port. The UART driver probe will
create path named "/dev/ttyNVTx".

Signed-off-by: Jacky Huang <ychuang3@nuvoton.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20230619032330.233796-2-ychuang570808@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-19 15:42:26 +02:00
Sherry Sun
e0edfdc158 tty: serial: fsl_lpuart: add earlycon for imx8ulp platform
Add earlycon support for imx8ulp platform.

Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Cc: stable <stable@kernel.org>
Link: https://lore.kernel.org/r/20230619080613.16522-1-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-19 15:41:25 +02:00
Martin Fuzzey
639949a703 tty: serial: imx: fix rs485 rx after tx
Since commit 79d0224f6b ("tty: serial: imx: Handle RS485 DE signal
active high") RS485 reception no longer works after a transmission.

The following scenario shows the problem:
	1) Open a port in RS485 mode
	2) Receive data from remote (OK)
	3) Transmit data to remote (OK)
	4) Receive data from remote (Nothing received)

In RS485 mode, imx_uart_start_tx() calls imx_uart_stop_rx() and, when the
transmission is complete, imx_uart_stop_tx() calls imx_uart_start_rx().

Since the above commit imx_uart_stop_rx() now sets the loopback bit but
imx_uart_start_rx() does not clear it causing the hardware to remain in
loopback mode and not receive external data.

Fix this by moving the existing loopback disable code to a helper function
and calling it from imx_uart_start_rx() too.

Fixes: 79d0224f6b ("tty: serial: imx: Handle RS485 DE signal active high")
Cc: stable@vger.kernel.org
Signed-off-by: Martin Fuzzey <martin.fuzzey@flowbird.group>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20230616104838.2729694-1-martin.fuzzey@flowbird.group
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-19 15:41:13 +02:00
Jonathan Corbet
173cb655ea docs: update some straggling Documentation/arm references
The Arm documentation has moved to Documentation/arch/arm; update the
last remaining references to match.

Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Chen-Yu Tsai <wens@csie.org>
Cc: Samuel Holland <samuel@sholland.org>
Cc: Thierry Reding <thierry.reding@gmail.com>
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> # for pwm
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2023-06-16 08:31:47 -06:00
Michal Sekletar
360c11e225 tty: tty_io: update timestamps on all device nodes
User space applications watch for timestamp changes on character device
files in order to determine idle time of a given terminal session. For
example, "w" program uses this information to populate the IDLE column
of its output [1]. Similarly, systemd-logind has optional feature where
it uses atime of the tty character device to determine if there was
activity on the terminal associated with the logind's session object. If
there was no activity for a configured period of time then logind will
terminate such session [2].

Now, usually (e.g. bash running on the terminal) the use of the terminal
will update timestamps (atime and mtime) on the corresponding terminal
character device. However, if access to the terminal, e.g. /dev/pts/0,
is performed through magic character device /dev/tty then such access
obviously changes the state of the terminal, however timestamps on the
device that correspond to the terminal (/dev/pts/0) are not updated.

This patch makes sure that we update timestamps on *all* character
devices that correspond to the given tty, because outside observers (w,
systemd-logind) are maybe checking these timestamps. Obviously, they can
not check timestamps on /dev/tty as that has per-process meaning.

[1] https://gitlab.com/procps-ng/procps/-/blob/v4.0.0/w.c#L286
[2] https://github.com/systemd/systemd/blob/v252/NEWS#L477

Signed-off-by: Michal Sekletar <msekleta@redhat.com>
Message-ID: <20230613172107.78138-1-msekleta@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-15 13:45:42 +02:00
Hui Li
4903fde804 tty: fix hang on tty device with no_room set
It is possible to hang pty devices in this case, the reader was
blocking at epoll on master side, the writer was sleeping at
wait_woken inside n_tty_write on slave side, and the write buffer
on tty_port was full, we found that the reader and writer would
never be woken again and blocked forever.

The problem was caused by a race between reader and kworker:
n_tty_read(reader):  n_tty_receive_buf_common(kworker):
copy_from_read_buf()|
                    |room = N_TTY_BUF_SIZE - (ldata->read_head - tail)
                    |room <= 0
n_tty_kick_worker() |
                    |ldata->no_room = true

After writing to slave device, writer wakes up kworker to flush
data on tty_port to reader, and the kworker finds that reader
has no room to store data so room <= 0 is met. At this moment,
reader consumes all the data on reader buffer and calls
n_tty_kick_worker to check ldata->no_room which is false and
reader quits reading. Then kworker sets ldata->no_room=true
and quits too.

If write buffer is not full, writer will wake kworker to flush data
again after following writes, but if write buffer is full and writer
goes to sleep, kworker will never be woken again and tty device is
blocked.

This problem can be solved with a check for read buffer size inside
n_tty_receive_buf_common, if read buffer is empty and ldata->no_room
is true, a call to n_tty_kick_worker is necessary to keep flushing
data to reader.

Cc: <stable@vger.kernel.org>
Fixes: 42458f41d0 ("n_tty: Ensure reader restarts worker for next reader")
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Hui Li <caelli@tencent.com>
Message-ID: <1680749090-14106-1-git-send-email-caelli@tencent.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-15 12:21:11 +02:00
Dan Carpenter
cef09673c3 serial: core: fix -EPROBE_DEFER handling in init
The -EPROBE_DEFER error path in serial_base_device_init() is a bit
awkward.  Before the call to device_initialize(dev) then we need to
manually release all the device resources.  And after the call then we
need to call put_device() to release the resources.  Doing either one
wrong will result in a leak or a use after free.

So let's wait to return -EPROBE_DEFER until after the call to
device_initialize(dev) so that way callers do not have to handle
-EPROBE_DEFER as a special case.  Now callers can just use put_device()
for clean up.

The second issue with the -EPROBE_DEFER path is that deferring is not
supposed to be a fatal error, but instead it's normal part of the
init process and the kernel recovers from it automatically.  That means
we should not print an error message but just a debug message on this
path.

Fixes: 539914240a ("serial: core: Fix probing serial_base_bus devices")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Message-ID: <18318adb-ab2c-4dcc-9f96-498a13d16b80@moroto.mountain>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-15 12:20:51 +02:00
Tony Lindgren
20a41a6261 serial: 8250_omap: Use force_suspend and resume for system suspend
We should not rely on autosuspend timeout for system suspend. Instead,
let's use force_suspend and force_resume functions. Otherwise the serial
port controller device may not be idled on suspend.

As we are doing a register write on suspend to configure the serial port,
we still need to runtime PM resume the port on suspend.

While at it, let's switch to pm_runtime_resume_and_get() and check for
errors returned. And let's add the missing line break before return to the
suspend function while at it.

Fixes: 09d8b2bdbc ("serial: 8250: omap: Provide ability to enable/disable UART as wakeup source")
Signed-off-by: Tony Lindgren <tony@atomide.com>
Tested-by: Dhruva Gole <d-gole@ti.com>
Message-ID: <20230614045922.4798-1-tony@atomide.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-15 12:20:49 +02:00
Christophe JAILLET
f3710f5e9e tty: serial: samsung_tty: Use abs() to simplify some code
Use abs() instead of hand-writing it.

Suggested-by: Walter Harms <wharms@bfs.de>
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Andi Shyti <andi.shyti@kernel.org>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Message-ID: <7bd165e82ed3675d4ddee343ab373031e995a126.1686412569.git.christophe.jaillet@wanadoo.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-13 12:33:22 +02:00
Christophe JAILLET
832e231cff tty: serial: samsung_tty: Fix a memory leak in s3c24xx_serial_getclk() when iterating clk
When the best clk is searched, we iterate over all possible clk.

If we find a better match, the previous one, if any, needs to be freed.
If a better match has already been found, we still need to free the new
one, otherwise it leaks.

Cc: <stable@vger.kernel.org> # v3.3+
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Andi Shyti <andi.shyti@kernel.org>
Fixes: 5f5a7a5578 ("serial: samsung: switch to clkdev based clock lookup")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Message-ID: <cf3e0053d2fc7391b2d906a86cd01a5ef15fb9dc.1686412569.git.christophe.jaillet@wanadoo.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-13 12:33:22 +02:00
Christophe JAILLET
a9c09546e9 tty: serial: samsung_tty: Fix a memory leak in s3c24xx_serial_getclk() in case of error
If clk_get_rate() fails, the clk that has just been allocated needs to be
freed.

Cc: <stable@vger.kernel.org> # v3.3+
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Andi Shyti <andi.shyti@kernel.org>
Fixes: 5f5a7a5578 ("serial: samsung: switch to clkdev based clock lookup")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Message-ID: <e4baf6039368f52e5a5453982ddcb9a330fc689e.1686412569.git.christophe.jaillet@wanadoo.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-13 12:33:22 +02:00
Robert Hodaszi
a82c3df955 tty: serial: fsl_lpuart: reduce RX watermark to 0 on LS1028A
LS1028A is using DMA with LPUART. Having RX watermark set to 1, means
DMA transactions are started only after receiving the second character.

On other platforms with newer LPUART IP, Receiver Idle Empty function
initiates the DMA request after the receiver is idling for 4 characters.
But this feature is missing on LS1028A, which is causing a 1-character
delay in the RX direction on this platform.

Set RX watermark to 0 to initiate RX DMA after each character.

Link: https://lore.kernel.org/linux-serial/20230607103459.1222426-1-robert.hodaszi@digi.com/
Fixes: 9ad9df8447 ("tty: serial: fsl_lpuart: Fix the wrong RXWATER setting for rx dma case")
Cc: stable <stable@kernel.org>
Signed-off-by: Robert Hodaszi <robert.hodaszi@digi.com>
Message-ID: <20230609121334.1878626-1-robert.hodaszi@digi.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-13 12:31:45 +02:00
Uwe Kleine-König
d9f59caf94 serial: 8250: Apply FSL workarounds also without SERIAL_8250_CONSOLE
The need to handle the FSL variant of 8250 in a special way is also
present without console support. So soften the dependency for
SERIAL_8250_FSL from SERIAL_8250_CONSOLE to SERIAL_8250. To handle
SERIAL_8250=m, the FSL code can be modular, too, thus SERIAL_8250_FSL
becomes tristate.

Compiling 8250_fsl as a module requires adding a module license so this
is added, too. While add it also add a appropriate module description.

As then SERIAL_OF_PLATFORM=y + SERIAL_8250_FSL=m is a valid combination
(if COMPILE_TEST is enabled on a platform that is neither PPC, ARM nor
ARM64), the check in 8250_of.c must be weakened a bit.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Message-ID: <20230609133932.786117-3-u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-13 12:27:05 +02:00
Dan Carpenter
52861a3be8 serial: core: don't kfree device managed data
The put_device() function will call serial_base_ctrl_release() or
serial_base_port_release() so these kfrees() are a double free bug.

Fixes: 84a9582fd2 ("serial: core: Start managing serial controllers to enable runtime PM")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Message-ID: <ZH7tsTmWY5b/4m+6@moroto>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-06 14:46:35 +02:00
Bernhard Seibold
306320034e serial: lantiq: add missing interrupt ack
Currently, the error interrupt is never acknowledged, so once active it
will stay active indefinitely, causing the handler to be called in an
infinite loop.

Fixes: 2f0fc4159a ("SERIAL: Lantiq: Add driver for MIPS Lantiq SOCs.")
Cc: <stable@vger.kernel.org>
Signed-off-by: Bernhard Seibold <mail@bernhard-seibold.de>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Message-ID: <20230602133029.546-1-mail@bernhard-seibold.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-06 14:45:34 +02:00
Chen-Yu Tsai
b6c7ff2693 serial: 8250_mtk: Simplify clock sequencing and runtime PM
The 8250_mtk driver's runtime PM support has some issues:

- The bus clock is enabled (through runtime PM callback) later than a
  register write
- runtime PM resume callback directly called in probe, but no
  pm_runtime_set_active() call is present
- UART PM function calls the callbacks directly, _and_ calls runtime
  PM API
- runtime PM callbacks try to do reference counting, adding yet another
  count between runtime PM and clocks

This fragile setup worked in a way, but broke recently with runtime PM
support added to the serial core. The system would hang when the UART
console was probed and brought up.

Tony provided some potential fixes [1][2], though they were still a bit
complicated. The 8250_dw driver, which the 8250_mtk driver might have
been based on, has a similar structure but simpler runtime PM usage.

Simplify clock sequencing and runtime PM support in the 8250_mtk driver.
Specifically, the clock is acquired enabled and assumed to be active,
unless toggled through runtime PM suspend/resume. Reference counting is
removed and left to the runtime PM core. The serial pm function now
only calls the runtime PM API.

[1] https://lore.kernel.org/linux-serial/20230602092701.GP14287@atomide.com/
[2] https://lore.kernel.org/linux-serial/20230605061511.GW14287@atomide.com/

Fixes: 84a9582fd2 ("serial: core: Start managing serial controllers to enable runtime PM")
Suggested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Message-ID: <20230606091747.2031168-1-wenst@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-06 14:43:13 +02:00
Raphael Gallais-Pou
643662d12b serial: st-asc: fix typo in property name
Changes the property name read in the driver according to the YAML.
According to device-tree documentation, property names should not
include underscores.

Signed-off-by: Raphael Gallais-Pou <rgallaispou@gmail.com>
Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com>
Message-ID: <20230604083558.16661-1-rgallaispou@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-06 14:42:58 +02:00
Greg Kroah-Hartman
2076b2a4a6 Merge 6.4-rc5 into tty-next
We need the tty fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-05 07:41:04 +02:00