6920 Commits

Author SHA1 Message Date
Fedor Pchelkin
b7f7a0402e Revert "tty: n_gsm: avoid call of sleeping functions from atomic context"
commit acdab4cb4ba7e5f94d2b422ebd7bf4bf68178fb2 upstream.

This reverts commit 902e02ea9385373ce4b142576eef41c642703955.

The above commit is reverted as the usage of tx_mutex seems not to solve
the problem described in 902e02ea9385 ("tty: n_gsm: avoid call of sleeping
functions from atomic context") and just moves the bug to another place.

Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru>
Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Reviewed-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20221008110221.13645-2-pchelkin@ispras.ru
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-12-08 11:23:59 +01:00
Lukas Wunner
f4db050958 serial: 8250: 8250_omap: Avoid RS485 RTS glitch on ->set_termios()
[ Upstream commit 038ee49fef18710bedd38b531d173ccd746b2d8d ]

RS485-enabled UART ports on TI Sitara SoCs with active-low polarity
exhibit a Transmit Enable glitch on ->set_termios():

omap8250_restore_regs(), which is called from omap_8250_set_termios(),
sets the TCRTLR bit in the MCR register and clears all other bits,
including RTS.  If RTS uses active-low polarity, it is now asserted
for no reason.

The TCRTLR bit is subsequently cleared by writing up->mcr to the MCR
register.  That variable is always zero, so the RTS bit is still cleared
(incorrectly so if RTS is active-high).

(up->mcr is not, as one might think, a cache of the MCR register's
current value.  Rather, it only caches a single bit of that register,
the AFE bit.  And it only does so if the UART supports the AFE bit,
which OMAP does not.  For details see serial8250_do_set_termios() and
serial8250_do_set_mctrl().)

Finally at the end of omap8250_restore_regs(), the MCR register is
restored (and RTS deasserted) by a call to up->port.ops->set_mctrl()
(which equals serial8250_set_mctrl()) and serial8250_em485_stop_tx().

So there's an RTS glitch between setting TCRTLR and calling
serial8250_em485_stop_tx().  Avoid by using a read-modify-write
when setting TCRTLR.

While at it, drop a redundant initialization of up->mcr.  As explained
above, the variable isn't used by the driver and it is already
initialized to zero because it is part of the static struct
serial8250_ports[] declared in 8250_core.c.  (Static structs are
initialized to zero per section 6.7.8 nr. 10 of the C99 standard.)

Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Su Bao Cheng <baocheng.su@siemens.com>
Tested-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Link: https://lore.kernel.org/r/6554b0241a2c7fd50f32576fdbafed96709e11e8.1664278942.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-02 17:40:05 +01:00
Ilpo Järvinen
5f4611fe01 serial: 8250_lpss: Configure DMA also w/o DMA filter
commit 1bfcbe5805d0cfc83c3544dcd01e0a282c1f6790 upstream.

If the platform doesn't use DMA device filter (as is the case with
Elkhart Lake), whole lpss8250_dma_setup() setup is skipped. This
results in skipping also *_maxburst setup which is undesirable.
Refactor lpss8250_dma_setup() to configure DMA even if filter is not
setup.

Cc: stable <stable@kernel.org>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20221108121952.5497-3-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-25 17:45:52 +01:00
Ilpo Järvinen
8679087e93 serial: 8250: Flush DMA Rx on RLSI
commit 1980860e0c8299316cddaf0992dd9e1258ec9d88 upstream.

Returning true from handle_rx_dma() without flushing DMA first creates
a data ordering hazard. If DMA Rx has handled any character at the
point when RLSI occurs, the non-DMA path handles any pending characters
jumping them ahead of those characters that are pending under DMA.

Fixes: 75df022b5f89 ("serial: 8250_dma: Fix RX handling")
Cc: <stable@vger.kernel.org>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20221108121952.5497-5-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-25 17:45:52 +01:00
Ilpo Järvinen
a5eaad87bf serial: 8250: Fall back to non-DMA Rx if IIR_RDI occurs
commit a931237cbea256aff13bb403da13a97b2d1605d9 upstream.

DW UART sometimes triggers IIR_RDI during DMA Rx when IIR_RX_TIMEOUT
should have been triggered instead. Since IIR_RDI has higher priority
than IIR_RX_TIMEOUT, this causes the Rx to hang into interrupt loop.
The problem seems to occur at least with some combinations of
small-sized transfers (I've reproduced the problem on Elkhart Lake PSE
UARTs).

If there's already an on-going Rx DMA and IIR_RDI triggers, fall
graciously back to non-DMA Rx. That is, behave as if IIR_RX_TIMEOUT had
occurred.

8250_omap already considers IIR_RDI similar to this change so its
nothing unheard of.

Fixes: 75df022b5f89 ("serial: 8250_dma: Fix RX handling")
Cc: <stable@vger.kernel.org>
Co-developed-by: Srikanth Thokala <srikanth.thokala@intel.com>
Signed-off-by: Srikanth Thokala <srikanth.thokala@intel.com>
Co-developed-by: Aman Kumar <aman.kumar@intel.com>
Signed-off-by: Aman Kumar <aman.kumar@intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20221108121952.5497-2-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-25 17:45:52 +01:00
Duoming Zhou
b8fe1a5aa7 tty: n_gsm: fix sleep-in-atomic-context bug in gsm_control_send
[ Upstream commit 7b7dfe4833c70a11cdfa51b38705103bd31eddaa ]

The function gsm_dlci_t1() is a timer handler that runs in an
atomic context, but it calls "kzalloc(..., GFP_KERNEL)" that
may sleep. As a result, the sleep-in-atomic-context bug will
happen. The process is shown below:

gsm_dlci_t1()
 gsm_dlci_open()
  gsm_modem_update()
   gsm_modem_upd_via_msc()
    gsm_control_send()
     kzalloc(sizeof(.., GFP_KERNEL) //may sleep

This patch changes the gfp_t parameter of kzalloc() from GFP_KERNEL to
GFP_ATOMIC in order to mitigate the bug.

Fixes: e1eaea46bb40 ("tty: n_gsm line discipline")
Signed-off-by: Duoming Zhou <duoming@zju.edu.cn>
Link: https://lore.kernel.org/r/20221002040709.27849-1-duoming@zju.edu.cn
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-25 17:45:43 +01:00
Shawn Guo
0a3160f4ff serial: imx: Add missing .thaw_noirq hook
[ Upstream commit 4561d8008a467cb05ac632a215391d6b787f40aa ]

The following warning is seen with non-console UART instance when
system hibernates.

[   37.371969] ------------[ cut here ]------------
[   37.376599] uart3_root_clk already disabled
[   37.380810] WARNING: CPU: 0 PID: 296 at drivers/clk/clk.c:952 clk_core_disable+0xa4/0xb0
...
[   37.506986] Call trace:
[   37.509432]  clk_core_disable+0xa4/0xb0
[   37.513270]  clk_disable+0x34/0x50
[   37.516672]  imx_uart_thaw+0x38/0x5c
[   37.520250]  platform_pm_thaw+0x30/0x6c
[   37.524089]  dpm_run_callback.constprop.0+0x3c/0xd4
[   37.528972]  device_resume+0x7c/0x160
[   37.532633]  dpm_resume+0xe8/0x230
[   37.536036]  hibernation_snapshot+0x288/0x430
[   37.540397]  hibernate+0x10c/0x2e0
[   37.543798]  state_store+0xc4/0xd0
[   37.547203]  kobj_attr_store+0x1c/0x30
[   37.550953]  sysfs_kf_write+0x48/0x60
[   37.554619]  kernfs_fop_write_iter+0x118/0x1ac
[   37.559063]  new_sync_write+0xe8/0x184
[   37.562812]  vfs_write+0x230/0x290
[   37.566214]  ksys_write+0x68/0xf4
[   37.569529]  __arm64_sys_write+0x20/0x2c
[   37.573452]  invoke_syscall.constprop.0+0x50/0xf0
[   37.578156]  do_el0_svc+0x11c/0x150
[   37.581648]  el0_svc+0x30/0x140
[   37.584792]  el0t_64_sync_handler+0xe8/0xf0
[   37.588976]  el0t_64_sync+0x1a0/0x1a4
[   37.592639] ---[ end trace 56e22eec54676d75 ]---

On hibernating, pm core calls into related hooks in sequence like:

    .freeze
    .freeze_noirq
    .thaw_noirq
    .thaw

With .thaw_noirq hook being absent, the clock will be disabled in a
unbalanced call which results the warning above.

    imx_uart_freeze()
        clk_prepare_enable()
    imx_uart_suspend_noirq()
        clk_disable()
    imx_uart_thaw
        clk_disable_unprepare()

Adding the missing .thaw_noirq hook as imx_uart_resume_noirq() will have
the call sequence corrected as below and thus fix the warning.

    imx_uart_freeze()
        clk_prepare_enable()
    imx_uart_suspend_noirq()
        clk_disable()
    imx_uart_resume_noirq()
        clk_enable()
    imx_uart_thaw
        clk_disable_unprepare()

Fixes: 09df0b3464e5 ("serial: imx: fix endless loop during suspend")
Reviewed-by: Martin Kaiser <martin@kaiser.cx>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Link: https://lore.kernel.org/r/20221012121353.2346280-1-shawn.guo@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-25 17:45:43 +01:00
Tony Lindgren
7e1f908e65 serial: 8250: omap: Flush PM QOS work on remove
[ Upstream commit d0b68629bd2fb61e0171a62f2e8da3db322f5cf6 ]

Rebinding 8250_omap in a loop will at some point produce a warning for
kernel/power/qos.c:296 cpu_latency_qos_update_request() with error
"cpu_latency_qos_update_request called for unknown object". Let's flush
the possibly pending PM QOS work scheduled from omap8250_runtime_suspend()
before we disable runtime PM.

Fixes: 61929cf0169d ("tty: serial: Add 8250-core based omap driver")
Signed-off-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20221028110044.54719-1-tony@atomide.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-25 17:45:43 +01:00
Tony Lindgren
d833cba201 serial: 8250: omap: Fix unpaired pm_runtime_put_sync() in omap8250_remove()
[ Upstream commit e3f0c638f428fd66b5871154b62706772045f91a ]

On remove, we get an error for "Runtime PM usage count underflow!". I guess
this driver is mostly built-in, and this issue has gone unnoticed for a
while. Somehow I did not catch this issue with my earlier fix done with
commit 4e0f5cc65098 ("serial: 8250_omap: Fix probe and remove for PM
runtime").

Fixes: 4e0f5cc65098 ("serial: 8250_omap: Fix probe and remove for PM runtime")
Signed-off-by: Tony Lindgren <tony@atomide.com>
Depends-on: dd8088d5a896 ("PM: runtime: Add pm_runtime_resume_and_get to deal with usage counter")
Link: https://lore.kernel.org/r/20221028105813.54290-1-tony@atomide.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-25 17:45:42 +01:00
Matthias Schiffer
b0b6ea651e serial: 8250_omap: remove wait loop from Errata i202 workaround
[ Upstream commit e828e56684d61b17317e0cfdef83791fa61cb76b ]

We were occasionally seeing the "Errata i202: timedout" on an AM335x
board when repeatedly opening and closing a UART connected to an active
sender. As new input may arrive at any time, it is possible to miss the
"RX FIFO empty" condition, forcing the loop to wait until it times out.

Nothing in the i202 Advisory states that such a wait is even necessary;
other FIFO clear functions like serial8250_clear_fifos() do not wait
either. For this reason, it seems safe to remove the wait, fixing the
mentioned issue.

Fixes: 61929cf0169d ("tty: serial: Add 8250-core based omap driver")
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
Link: https://lore.kernel.org/r/20221013112339.2540767-1-matthias.schiffer@ew.tq-group.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-25 17:45:42 +01:00
Tony Lindgren
f14c312c21 serial: 8250: omap: Fix missing PM runtime calls for omap8250_set_mctrl()
[ Upstream commit 93810191f5d23652c0b8a1a9b3a4a89d6fd5063e ]

There are cases where omap8250_set_mctrl() may get called after the
UART has already autoidled causing an asynchronous external abort.

This can happen on ttyport_open():

mem_serial_in from omap8250_set_mctrl+0x38/0xa0
omap8250_set_mctrl from uart_update_mctrl+0x4c/0x58
uart_update_mctrl from uart_dtr_rts+0x60/0xa8
uart_dtr_rts from tty_port_block_til_ready+0xd0/0x2a8
tty_port_block_til_ready from uart_open+0x14/0x1c
uart_open from ttyport_open+0x64/0x148

And on ttyport_close():

omap8250_set_mctrl from uart_update_mctrl+0x3c/0x48
uart_update_mctrl from uart_dtr_rts+0x54/0x9c
uart_dtr_rts from tty_port_shutdown+0x78/0x9c
tty_port_shutdown from tty_port_close+0x3c/0x74
tty_port_close from ttyport_close+0x40/0x58

It can also happen on disassociate_ctty() calling uart_shutdown()
that ends up calling omap8250_set_mctrl().

Let's fix the issue by adding missing PM runtime calls to
omap8250_set_mctrl(). To do this, we need to add __omap8250_set_mctrl()
that can be called from both omap8250_set_mctrl(), and from runtime PM
resume path when restoring the registers.

Fixes: 61929cf0169d ("tty: serial: Add 8250-core based omap driver")
Reported-by: Merlijn Wajer <merlijn@wizzup.org>
Reported-by: Romain Naour <romain.naour@smile.fr>
Reported-by: Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com>
Tested-by: Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Depends-on: dd8088d5a896 ("PM: runtime: Add pm_runtime_resume_and_get to deal with usage counter")
Link: https://lore.kernel.org/r/20221024063613.25943-1-tony@atomide.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-25 17:45:42 +01:00
Ilpo Järvinen
85cdbf04b4 serial: 8250: Remove serial_rs485 sanitization from em485
[ Upstream commit 84f2faa7852e1f55d89bb0c99b3a672b87b11f87 ]

Serial core handles serial_rs485 sanitization.

When em485 init fails, there are two possible paths of entry:

  1) uart_rs485_config (init path) that fully clears port->rs485 on
     error.

  2) ioctl path with a pre-existing, valid port->rs485 unto which the
     kernel falls back on error and port->rs485 should therefore be
     kept untouched. The temporary rs485 struct is not returned to
     userspace in case of error so its flag don't matter.

...Thus SER_RS485_ENABLED clearing on error can/should be dropped.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220606100433.13793-37-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stable-dep-of: 93810191f5d2 ("serial: 8250: omap: Fix missing PM runtime calls for omap8250_set_mctrl()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-25 17:45:42 +01:00
Helge Deller
814af9a32b parisc: Make 8250_gsc driver dependend on CONFIG_PARISC
commit e8a18e3f00f3ee8d07c17ab1ea3ad4df4a3b6fe0 upstream.

Although the name of the driver 8250_gsc.c suggests that it handles
only serial ports on the GSC bus, it does handle serial ports listed
in the parisc machine inventory as well, e.g. the serial ports in a
C8000 PCI-only workstation.

Change the dependency to CONFIG_PARISC, so that the driver gets included
in the kernel even if CONFIG_GSC isn't set.

Reported-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-10 18:14:27 +01:00
Lukas Wunner
028fcabd8a serial: ar933x: Deassert Transmit Enable on ->rs485_config()
commit 3a939433ddc1bab98be028903aaa286e5e7461d7 upstream.

The ar933x_uart driver neglects to deassert Transmit Enable when
->rs485_config() is invoked.  Fix it.

Fixes: 9be1064fe524 ("serial: ar933x_uart: add RS485 support")
Cc: stable@vger.kernel.org # v5.7+
Cc: Daniel Golle <daniel@makrotopia.org>
Reviewed-by: Ilpo JÀrvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-10 18:14:14 +01:00
Maciej W. Rozycki
e6da7808c9 serial: 8250: Let drivers request full 16550A feature probing
[ Upstream commit 9906890c89e4dbd900ed87ad3040080339a7f411 ]

A SERIAL_8250_16550A_VARIANTS configuration option has been recently
defined that lets one request the 8250 driver not to probe for 16550A
device features so as to reduce the driver's device startup time in
virtual machines.

Some actual hardware devices require these features to have been fully
determined however for their driver to work correctly, so define a flag
to let drivers request full 16550A feature probing on a device-by-device
basis if required regardless of the SERIAL_8250_16550A_VARIANTS option
setting chosen.

Fixes: dc56ecb81a0a ("serial: 8250: Support disabling mdelay-filled probes of 16550A variants")
Cc: stable@vger.kernel.org # v5.6+
Reported-by: Anders Blomdell <anders.blomdell@control.lth.se>
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2209202357520.41633@angie.orcam.me.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-10 18:14:14 +01:00
Lukas Wunner
26a2b9c468 serial: Deassert Transmit Enable on probe in driver-specific way
commit 7c7f9bc986e698873b489c371a08f206979d06b7 upstream.

When a UART port is newly registered, uart_configure_port() seeks to
deassert RS485 Transmit Enable by setting the RTS bit in port->mctrl.
However a number of UART drivers interpret a set RTS bit as *assertion*
instead of deassertion:  Affected drivers include those using
serial8250_em485_config() (except 8250_bcm2835aux.c) and some using
mctrl_gpio (e.g. imx.c).

Since the interpretation of the RTS bit is driver-specific, it is not
suitable as a means to centrally deassert Transmit Enable in the serial
core.  Instead, the serial core must call on drivers to deassert it in
their driver-specific way.  One way to achieve that is to call
->rs485_config().  It implicitly deasserts Transmit Enable.

So amend uart_configure_port() and uart_resume_port() to invoke
uart_rs485_config().  That allows removing calls to uart_rs485_config()
from drivers' ->probe() hooks and declaring the function static.

Skip any invocation of ->set_mctrl() if RS485 is enabled.  RS485 has no
hardware flow control, so the modem control lines are irrelevant and
need not be touched.  When leaving RS485 mode, reset the modem control
lines to the state stored in port->mctrl.  That way, UARTs which are
muxed between RS485 and RS232 transceivers drive the lines correctly
when switched to RS232.  (serial8250_do_startup() historically raises
the OUT1 modem signal because otherwise interrupts are not signaled on
ancient PC UARTs, but I believe that no longer applies to modern,
RS485-capable UARTs and is thus safe to be skipped.)

imx.c modifies port->mctrl whenever Transmit Enable is asserted and
deasserted.  Stop it from doing that so port->mctrl reflects the RS232
line state.

8250_omap.c deasserts Transmit Enable on ->runtime_resume() by calling
->set_mctrl().  Because that is now a no-op in RS485 mode, amend the
function to call serial8250_em485_stop_tx().

fsl_lpuart.c retrieves and applies the RS485 device tree properties
after registering the UART port.  Because applying now happens on
registration in uart_configure_port(), move retrieval of the properties
ahead of uart_add_one_port().

Link: https://lore.kernel.org/all/20220329085050.311408-1-matthias.schiffer@ew.tq-group.com/
Link: https://lore.kernel.org/all/8f538a8903795f22f9acc94a9a31b03c9c4ccacb.camel@ginzinger.com/
Fixes: d3b3404df318 ("serial: Fix incorrect rs485 polarity on uart open")
Cc: stable@vger.kernel.org # v4.14+
Reported-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
Reported-by: Roosen Henri <Henri.Roosen@ginzinger.com>
Tested-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Link: https://lore.kernel.org/r/2de36eba3fbe11278d5002e4e501afe0ceaca039.1663863805.git.lukas@wunner.de
Signed-off-by: Daisuke Mizobuchi <mizo@atmark-techno.com>
Signed-off-by: Dominique Martinet <dominique.martinet@atmark-techno.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-03 23:57:54 +09:00
Lino Sanfilippo
4a230f65d6 serial: core: move RS485 configuration tasks from drivers into core
commit 0ed12afa5655512ee418047fb3546d229df20aa1 upstream.

Several drivers that support setting the RS485 configuration via userspace
implement one or more of the following tasks:

- in case of an invalid RTS configuration (both RTS after send and RTS on
  send set or both unset) fall back to enable RTS on send and disable RTS
  after send

- nullify the padding field of the returned serial_rs485 struct

- copy the configuration into the uart port struct

- limit RTS delays to 100 ms

Move these tasks into the serial core to make them generic and to provide
a consistent behaviour among all drivers.

Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Link: https://lore.kernel.org/r/20220410104642.32195-2-LinoSanfilippo@gmx.de
Signed-off-by: Daisuke Mizobuchi <mizo@atmark-techno.com>
Signed-off-by: Dominique Martinet <dominique.martinet@atmark-techno.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-03 23:57:54 +09:00
Pali Rohár
8f740c11d8 serial: 8250: Fix restoring termios speed after suspend
[ Upstream commit 379a33786d489ab81885ff0b3935cfeb36137fea ]

Since commit edc6afc54968 ("tty: switch to ktermios and new framework")
termios speed is no longer stored only in c_cflag member but also in new
additional c_ispeed and c_ospeed members. If BOTHER flag is set in c_cflag
then termios speed is stored only in these new members.

Since commit 027b57170bf8 ("serial: core: Fix initializing and restoring
termios speed") termios speed is available also in struct console.

So properly restore also c_ispeed and c_ospeed members after suspend to fix
restoring termios speed which is not represented by Bnnn constant.

Fixes: 4516d50aabed ("serial: 8250: Use canary to restart console after suspend")
Signed-off-by: Pali Rohár <pali@kernel.org>
Link: https://lore.kernel.org/r/20220924104324.4035-1-pali@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-26 13:25:37 +02:00
Sherry Sun
9a56ade124 tty: serial: fsl_lpuart: disable dma rx/tx use flags in lpuart_dma_shutdown
[ Upstream commit 316ae95c175a7d770d1bfe4c011192712f57aa4a ]

lpuart_dma_shutdown tears down lpuart dma, but lpuart_flush_buffer can
still occur which in turn tries to access dma apis if lpuart_dma_tx_use
flag is true. At this point since dma is torn down, these dma apis can
abort. Set lpuart_dma_tx_use and the corresponding rx flag
lpuart_dma_rx_use to false in lpuart_dma_shutdown so that dmas are not
accessed after they are relinquished.

Otherwise, when try to kill btattach, kernel may panic. This patch may
fix this issue.
root@imx8ulpevk:~# btattach -B /dev/ttyLP2 -S 115200
^C[   90.182296] Internal error: synchronous external abort: 96000210 [#1] PREEMPT SMP
[   90.189806] Modules linked in: moal(O) mlan(O)
[   90.194258] CPU: 0 PID: 503 Comm: btattach Tainted: G           O      5.15.32-06136-g34eecdf2f9e4 #37
[   90.203554] Hardware name: NXP i.MX8ULP 9X9 EVK (DT)
[   90.208513] pstate: 600000c5 (nZCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[   90.215470] pc : fsl_edma3_disable_request+0x8/0x60
[   90.220358] lr : fsl_edma3_terminate_all+0x34/0x20c
[   90.225237] sp : ffff800013f0bac0
[   90.228548] x29: ffff800013f0bac0 x28: 0000000000000001 x27: ffff000008404800
[   90.235681] x26: ffff000008404960 x25: ffff000008404a08 x24: ffff000008404a00
[   90.242813] x23: ffff000008404a60 x22: 0000000000000002 x21: 0000000000000000
[   90.249946] x20: ffff800013f0baf8 x19: ffff00000559c800 x18: 0000000000000000
[   90.257078] x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000
[   90.264211] x14: 0000000000000003 x13: 0000000000000000 x12: 0000000000000040
[   90.271344] x11: ffff00000600c248 x10: ffff800013f0bb10 x9 : ffff000057bcb090
[   90.278477] x8 : fffffc0000241a08 x7 : ffff00000534ee00 x6 : ffff000008404804
[   90.285609] x5 : 0000000000000000 x4 : 0000000000000000 x3 : ffff0000055b3480
[   90.292742] x2 : ffff8000135c0000 x1 : ffff00000534ee00 x0 : ffff00000559c800
[   90.299876] Call trace:
[   90.302321]  fsl_edma3_disable_request+0x8/0x60
[   90.306851]  lpuart_flush_buffer+0x40/0x160
[   90.311037]  uart_flush_buffer+0x88/0x120
[   90.315050]  tty_driver_flush_buffer+0x20/0x30
[   90.319496]  hci_uart_flush+0x44/0x90
[   90.323162]  +0x34/0x12c
[   90.327253]  tty_ldisc_close+0x38/0x70
[   90.331005]  tty_ldisc_release+0xa8/0x190
[   90.335018]  tty_release_struct+0x24/0x8c
[   90.339022]  tty_release+0x3ec/0x4c0
[   90.342593]  __fput+0x70/0x234
[   90.345652]  ____fput+0x14/0x20
[   90.348790]  task_work_run+0x84/0x17c
[   90.352455]  do_exit+0x310/0x96c
[   90.355688]  do_group_exit+0x3c/0xa0
[   90.359259]  __arm64_sys_exit_group+0x1c/0x20
[   90.363609]  invoke_syscall+0x48/0x114
[   90.367362]  el0_svc_common.constprop.0+0xd4/0xfc
[   90.372068]  do_el0_svc+0x2c/0x94
[   90.375379]  el0_svc+0x28/0x80
[   90.378438]  el0t_64_sync_handler+0xa8/0x130
[   90.382711]  el0t_64_sync+0x1a0/0x1a4
[   90.386376] Code: 17ffffda d503201f d503233f f9409802 (b9400041)
[   90.392467] ---[ end trace 2f60524b4a43f1f6 ]---
[   90.397073] note: btattach[503] exited with preempt_count 1
[   90.402636] Fixing recursive fault but reboot is needed!

Fixes: 6250cc30c4c4 ("tty: serial: fsl_lpuart: Use scatter/gather DMA for Tx")
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Thara Gopinath <tgopinath@microsoft.com>
Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Link: https://lore.kernel.org/r/20220920111703.1532-1-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-26 13:25:36 +02:00
Ilpo Järvinen
572fb97fce serial: 8250: Toggle IER bits on only after irq has been set up
[ Upstream commit 039d4926379b1d1c17b51cf21c500a5eed86899e ]

Invoking TIOCVHANGUP on 8250_mid port on Ice Lake-D and then reopening
the port triggers these faults during serial8250_do_startup():

  DMAR: DRHD: handling fault status reg 3
  DMAR: [DMA Write NO_PASID] Request device [00:1a.0] fault addr 0x0 [fault reason 0x05] PTE Write access is not set

If the IRQ hasn't been set up yet, the UART will have zeroes in its MSI
address/data registers. Disabling the IRQ at the interrupt controller
won't stop the UART from performing a DMA write to the address programmed
in its MSI address register (zero) when it wants to signal an interrupt.

The UARTs (in Ice Lake-D) implement PCI 2.1 style MSI without masking
capability, so there is no way to mask the interrupt at the source PCI
function level, except disabling the MSI capability entirely, but that
would cause it to fall back to INTx# assertion, and the PCI specification
prohibits disabling the MSI capability as a way to mask a function's
interrupt service request.

The MSI address register is zeroed by the hangup as the irq is freed.
The interrupt is signalled during serial8250_do_startup() performing a
THRE test that temporarily toggles THRI in IER. The THRE test currently
occurs before UART's irq (and MSI address) is properly set up.

Refactor serial8250_do_startup() such that irq is set up before the
THRE test. The current irq setup code is intermixed with the timer
setup code. As THRE test must be performed prior to the timer setup,
extract it into own function and call it only after the THRE test.

The ->setup_timer() needs to be part of the struct uart_8250_ops in
order to not create circular dependency between 8250 and 8250_base
modules.

Fixes: 40b36daad0ac ("[PATCH] 8250 UART backup timer")
Reported-by: Lennert Buytenhek <buytenh@arista.com>
Tested-by: Lennert Buytenhek <buytenh@arista.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220922070005.2965-1-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-26 13:25:36 +02:00
Christophe JAILLET
3fbfa5e3cc serial: 8250: Add an empty line and remove some useless {}
[ Upstream commit 26f7591632d74f637f346f5d642d8ebe6b433fc9 ]

This fixes the following checkpatch.pl warnings:
   WARNING: Missing a blank line after declarations
   WARNING: braces {} are not necessary for any arm of this statement

Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/257ffd691b4a062ad017333c9430d69da6dbd29a.1619594713.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stable-dep-of: 039d4926379b ("serial: 8250: Toggle IER bits on only after irq has been set up")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-26 13:25:36 +02:00
Dan Carpenter
71ffe5111f drivers: serial: jsm: fix some leaks in probe
[ Upstream commit 1d5859ef229e381f4db38dce8ed58e4bf862006b ]

This error path needs to unwind instead of just returning directly.

Fixes: 03a8482c17dd ("drivers: serial: jsm: Enable support for Digi Classic adapters")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/YyxFh1+lOeZ9WfKO@kili
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-26 13:25:36 +02:00
Shubhrajyoti Datta
551b87976a tty: xilinx_uartps: Fix the ignore_status
[ Upstream commit b8a6c3b3d4654fba19881cc77da61eac29f57cae ]

Currently the ignore_status is not considered in the isr.
Add a check to add the ignore_status.

Fixes: 61ec9016988f ("tty/serial: add support for Xilinx PS UART")
Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Link: https://lore.kernel.org/r/20220729114748.18332-5-shubhrajyoti.datta@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-26 13:25:32 +02:00
Ilpo Järvinen
fb189aa1be serial: tegra-tcu: Use uart_xmit_advance(), fixes icount.tx accounting
commit 1d10cd4da593bc0196a239dcc54dac24b6b0a74e upstream.

Tx'ing does not correctly account Tx'ed characters into icount.tx.
Using uart_xmit_advance() fixes the problem.

Fixes: 2d908b38d409 ("serial: Add Tegra Combined UART driver")
Cc: <stable@vger.kernel.org> # serial: Create uart_xmit_advance()
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220901143934.8850-4-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-28 11:10:38 +02:00
Ilpo Järvinen
e1993864a9 serial: tegra: Use uart_xmit_advance(), fixes icount.tx accounting
commit 754f68044c7dd6c52534ba3e0f664830285c4b15 upstream.

DMA complete & stop paths did not correctly account Tx'ed characters
into icount.tx. Using uart_xmit_advance() fixes the problem.

Fixes: e9ea096dd225 ("serial: tegra: add serial driver")
Cc: <stable@vger.kernel.org> # serial: Create uart_xmit_advance()
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220901143934.8850-3-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-28 11:10:37 +02:00
Sergiu Moga
345bdea212 tty: serial: atmel: Preserve previous USART mode if RS485 disabled
[ Upstream commit 692a8ebcfc24f4a5bea0eb2967e450f584193da6 ]

Whenever the atmel_rs485_config() driver method would be called,
the USART mode is reset to normal mode before even checking if
RS485 flag is set, thus resulting in losing the previous USART
mode in the case where the checking fails.

Some tools, such as `linux-serial-test`, lead to the driver calling
this method when doing the setup of the serial port: after setting the
port mode (Hardware Flow Control, Normal Mode, RS485 Mode, etc.),
`linux-serial-test` tries to enable/disable RS485 depending on
the commandline arguments that were passed.

Example of how this issue could reveal itself:
When doing a serial communication with Hardware Flow Control through
`linux-serial-test`, the tool would lead to the driver roughly doing
the following:
- set the corresponding bit to 1 (ATMEL_US_USMODE_HWHS bit in the
ATMEL_US_MR register) through the atmel_set_termios() to enable
Hardware Flow Control
- disable RS485 through the atmel_config_rs485() method
Thus, when the latter is called, the mode will be reset and the
previously set bit is unset, leaving USART in normal mode instead of
the expected Hardware Flow Control mode.

This fix ensures that this reset is only done if the checking for
RS485 succeeds and that the previous mode is preserved otherwise.

Fixes: e8faff7330a35 ("ARM: 6092/1: atmel_serial: support for RS485 communications")
Cc: stable <stable@kernel.org>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Sergiu Moga <sergiu.moga@microchip.com>
Link: https://lore.kernel.org/r/20220824142902.502596-1-sergiu.moga@microchip.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-28 11:10:22 +02:00
Lino Sanfilippo
730f78c51b serial: atmel: remove redundant assignment in rs485_config
[ Upstream commit 60efd0513916f195dd85bfbf21653f74f9ab019c ]

In uart_set_rs485_config() the serial core already assigns the passed
serial_rs485 struct to the uart port.

So remove the assignment from the drivers rs485_config() function to avoid
redundancy.

Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Acked-by: Richard Genoud <richard.genoud@gmail.com>
Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Link: https://lore.kernel.org/r/20220410104642.32195-10-LinoSanfilippo@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stable-dep-of: 692a8ebcfc24 ("tty: serial: atmel: Preserve previous USART mode if RS485 disabled")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-28 11:10:22 +02:00
Johan Hovold
107c6b6058 Revert "serial: 8250: Fix reporting real baudrate value in c_ospeed field"
commit d02b006b29de14968ba4afa998bede0d55469e29 upstream.

This reverts commit 32262e2e429cdb31f9e957e997d53458762931b7.

The commit in question claims to determine the inverse of
serial8250_get_divisor() but failed to notice that some drivers override
the default implementation using a get_divisor() callback.

This means that the computed line-speed values can be completely wrong
and results in regular TCSETS requests failing (the incorrect values
would also be passed to any overridden set_divisor() callback).

Similarly, it also failed to honour the old (deprecated) ASYNC_SPD_FLAGS
and would break applications relying on those when re-encoding the
actual line speed.

There are also at least two quirks, UART_BUG_QUOT and an OMAP1510
workaround, which were happily ignored and that are now broken.

Finally, even if the offending commit were to be implemented correctly,
this is a new feature and not something which should be backported to
stable.

Cc: Pali Rohár <pali@kernel.org>
Fixes: 32262e2e429c ("serial: 8250: Fix reporting real baudrate value in c_ospeed field")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20211007133146.28949-1-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-23 14:16:59 +02:00
Pali Rohár
59819f0aaf serial: 8250: Fix reporting real baudrate value in c_ospeed field
[ Upstream commit 32262e2e429cdb31f9e957e997d53458762931b7 ]

In most cases it is not possible to set exact baudrate value to hardware.

So fix reporting real baudrate value which was set to hardware via c_ospeed
termios field. It can be retrieved by ioctl(TCGETS2) from userspace.

Real baudrate value is calculated from chosen hardware divisor and base
clock. It is implemented in a new function serial8250_compute_baud_rate()
which is inverse of serial8250_get_divisor() function.

With this change is fixed also UART timeout value (it is updated via
uart_update_timeout() function), which is calculated from the now fixed
baudrate value too.

Cc: stable@vger.kernel.org
Signed-off-by: Pali Rohár <pali@kernel.org>
Link: https://lore.kernel.org/r/20210927093704.19768-1-pali@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-23 14:16:55 +02:00
Fedor Pchelkin
eb75efdec8 tty: n_gsm: avoid call of sleeping functions from atomic context
commit 902e02ea9385373ce4b142576eef41c642703955 upstream.

Syzkaller reports the following problem:

BUG: sleeping function called from invalid context at kernel/printk/printk.c:2347
in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 1105, name: syz-executor423
3 locks held by syz-executor423/1105:
 #0: ffff8881468b9098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x90 drivers/tty/tty_ldisc.c:266
 #1: ffff8881468b9130 (&tty->atomic_write_lock){+.+.}-{3:3}, at: tty_write_lock drivers/tty/tty_io.c:952 [inline]
 #1: ffff8881468b9130 (&tty->atomic_write_lock){+.+.}-{3:3}, at: do_tty_write drivers/tty/tty_io.c:975 [inline]
 #1: ffff8881468b9130 (&tty->atomic_write_lock){+.+.}-{3:3}, at: file_tty_write.constprop.0+0x2a8/0x8e0 drivers/tty/tty_io.c:1118
 #2: ffff88801b06c398 (&gsm->tx_lock){....}-{2:2}, at: gsmld_write+0x5e/0x150 drivers/tty/n_gsm.c:2717
irq event stamp: 3482
hardirqs last  enabled at (3481): [<ffffffff81d13343>] __get_reqs_available+0x143/0x2f0 fs/aio.c:946
hardirqs last disabled at (3482): [<ffffffff87d39722>] __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:108 [inline]
hardirqs last disabled at (3482): [<ffffffff87d39722>] _raw_spin_lock_irqsave+0x52/0x60 kernel/locking/spinlock.c:159
softirqs last  enabled at (3408): [<ffffffff87e01002>] asm_call_irq_on_stack+0x12/0x20
softirqs last disabled at (3401): [<ffffffff87e01002>] asm_call_irq_on_stack+0x12/0x20
Preemption disabled at:
[<0000000000000000>] 0x0
CPU: 2 PID: 1105 Comm: syz-executor423 Not tainted 5.10.137-syzkaller #0
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x107/0x167 lib/dump_stack.c:118
 ___might_sleep.cold+0x1e8/0x22e kernel/sched/core.c:7304
 console_lock+0x19/0x80 kernel/printk/printk.c:2347
 do_con_write+0x113/0x1de0 drivers/tty/vt/vt.c:2909
 con_write+0x22/0xc0 drivers/tty/vt/vt.c:3296
 gsmld_write+0xd0/0x150 drivers/tty/n_gsm.c:2720
 do_tty_write drivers/tty/tty_io.c:1028 [inline]
 file_tty_write.constprop.0+0x502/0x8e0 drivers/tty/tty_io.c:1118
 call_write_iter include/linux/fs.h:1903 [inline]
 aio_write+0x355/0x7b0 fs/aio.c:1580
 __io_submit_one fs/aio.c:1952 [inline]
 io_submit_one+0xf45/0x1a90 fs/aio.c:1999
 __do_sys_io_submit fs/aio.c:2058 [inline]
 __se_sys_io_submit fs/aio.c:2028 [inline]
 __x64_sys_io_submit+0x18c/0x2f0 fs/aio.c:2028
 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xc6

The problem happens in the following control flow:

gsmld_write(...)
spin_lock_irqsave(&gsm->tx_lock, flags) // taken a spinlock on TX data
 con_write(...)
  do_con_write(...)
   console_lock()
    might_sleep() // -> bug

As far as console_lock() might sleep it should not be called with
spinlock held.

The patch replaces tx_lock spinlock with mutex in order to avoid the
problem.

Found by Linux Verification Center (linuxtesting.org) with Syzkaller.

Fixes: 32dd59f ("tty: n_gsm: fix race condition in gsmld_write()")
Cc: stable <stable@kernel.org>
Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru>
Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Link: https://lore.kernel.org/r/20220829131640.69254-3-pchelkin@ispras.ru
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-15 11:32:02 +02:00
Tetsuo Handa
fb6cadd2a3 tty: n_gsm: initialize more members at gsm_alloc_mux()
commit 4bb1a53be85fcb1e24c14860e326a00cdd362c28 upstream.

syzbot is reporting use of uninitialized spinlock at gsmld_write() [1], for
commit 32dd59f ("tty: n_gsm: fix race condition in gsmld_write()")
allows accessing gsm->tx_lock before gsm_activate_mux() initializes it.

Since object initialization should be done right after allocation in order
to avoid accessing uninitialized memory, move initialization of
timer/work/waitqueue/spinlock from gsmld_open()/gsm_activate_mux() to
gsm_alloc_mux().

Link: https://syzkaller.appspot.com/bug?extid=cf155def4e717db68a12 [1]
Fixes: 32dd59f ("tty: n_gsm: fix race condition in gsmld_write()")
Reported-by: syzbot <syzbot+cf155def4e717db68a12@syzkaller.appspotmail.com>
Tested-by: syzbot <syzbot+cf155def4e717db68a12@syzkaller.appspotmail.com>
Cc: stable <stable@kernel.org>
Acked-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Link: https://lore.kernel.org/r/2110618e-57f0-c1ce-b2ad-b6cacef3f60e@I-love.SAKURA.ne.jp
Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-15 11:32:02 +02:00
Sherry Sun
b202400c9c tty: serial: lpuart: disable flow control while waiting for the transmit engine to complete
commit d5a2e0834364377a5d5a2fff1890a0b3f0bafd1f upstream.

When the user initializes the uart port, and waits for the transmit
engine to complete in lpuart32_set_termios(), if the UART TX fifo has
dirty data and the UARTMODIR enable the flow control, the TX fifo may
never be empty. So here we should disable the flow control first to make
sure the transmit engin can complete.

Fixes: 380c966c093e ("tty: serial: fsl_lpuart: add 32-bit register interface support")
Cc: stable <stable@kernel.org>
Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Link: https://lore.kernel.org/r/20220821101527.10066-1-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-08 11:11:37 +02:00
Helge Deller
989201bb8c vt: Clear selection before changing the font
commit 566f9c9f89337792070b5a6062dff448b3e7977f upstream.

When changing the console font with ioctl(KDFONTOP) the new font size
can be bigger than the previous font. A previous selection may thus now
be outside of the new screen size and thus trigger out-of-bounds
accesses to graphics memory if the selection is removed in
vc_do_resize().

Prevent such out-of-memory accesses by dropping the selection before the
various con_font_set() console handlers are called.

Reported-by: syzbot+14b0e8f3fd1612e35350@syzkaller.appspotmail.com
Cc: stable <stable@kernel.org>
Tested-by: Khalid Masum <khalid.masum.92@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Link: https://lore.kernel.org/r/YuV9apZGNmGfjcor@p100
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-08 11:11:37 +02:00
Shenwei Wang
6ccd69141b serial: fsl_lpuart: RS485 RTS polariy is inverse
commit 846651eca073e2e02e37490a4a52752415d84781 upstream.

The setting of RS485 RTS polarity is inverse in the current driver.

When the property of 'rs485-rts-active-low' is enabled in the dts node,
the RTS signal should be LOW during sending. Otherwise, if there is no
such a property, the RTS should be HIGH during sending.

Fixes: 03895cf41d18 ("tty: serial: fsl_lpuart: Add support for RS-485")
Cc: stable <stable@kernel.org>
Signed-off-by: Nicolas Diaz <nicolas.diaz@nxp.com>
Signed-off-by: Shenwei Wang <shenwei.wang@nxp.com>
Link: https://lore.kernel.org/r/20220805144529.604856-1-shenwei.wang@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-08 11:11:37 +02:00
Liang He
81939c4fbc tty: serial: Fix refcount leak bug in ucc_uart.c
[ Upstream commit d24d7bb2cd947676f9b71fb944d045e09b8b282f ]

In soc_info(), of_find_node_by_type() will return a node pointer
with refcount incremented. We should use of_node_put() when it is
not used anymore.

Acked-by: Timur Tabi <timur@kernel.org>
Signed-off-by: Liang He <windhl@126.com>
Link: https://lore.kernel.org/r/20220618060850.4058525-1-windhl@126.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-25 11:38:18 +02:00
Maciej W. Rozycki
e41b3b8831 serial: 8250: Fold EndRun device support into OxSemi Tornado code
[ Upstream commit 1f32c65bad24b9787d3e52843de375430e3df822 ]

The EndRun PTP/1588 dual serial port device is based on the Oxford
Semiconductor OXPCIe952 UART device with the PCI vendor:device ID set
for EndRun Technologies and uses the same sequence to determine the
number of ports available.  Despite that we have duplicate code
specific to the EndRun device.

Remove redundant code then and factor out OxSemi Tornado device
detection.

Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2204181516220.9383@angie.orcam.me.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-21 15:16:19 +02:00
Andy Shevchenko
194dc559e6 serial: 8250_pci: Replace dev_*() by pci_*() macros
[ Upstream commit 1177384179416c7136e1348f07609e0da1ae6b91 ]

PCI subsystem provides convenient shortcut macros for message printing.
Use those macros instead of dev_*().

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Jiri Slaby <jslaby@kernel.org>
Link: https://lore.kernel.org/r/20211022135147.70965-3-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-21 15:16:19 +02:00
Andy Shevchenko
297e2fd08a serial: 8250_pci: Refactor the loop in pci_ite887x_init()
[ Upstream commit 35b4f17231923e2f64521bdf7a2793ce2c3c74a6 ]

The loop can be refactored by using ARRAY_SIZE() instead of NULL terminator.
This reduces code base and makes it easier to read and understand.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Jiri Slaby <jslaby@kernel.org>
Link: https://lore.kernel.org/r/20211022135147.70965-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-21 15:16:19 +02:00
Maciej W. Rozycki
3110e5a49b serial: 8250: Correct the clock for OxSemi PCIe devices
[ Upstream commit 6cbe45d8ac9316ceedd0749759bd54caf03f7012 ]

Oxford Semiconductor PCIe (Tornado) serial port devices are driven by a
fixed 62.5MHz clock input derived from the 100MHz PCI Express clock.

In the enhanced (650) mode, which we select in `autoconfig_has_efr' by
setting the ECB bit in the EFR register, and in the absence of clock
reconfiguration, which we currently don't do, the clock rate is divided
only by the oversampling rate of 16 as it is supplied to the baud rate
generator, yielding the baud base of 3906250.  This comes from the reset
values of the TCR and MCR[7] registers which are both zero[1][2][3][4],
choosing the oversampling rate of 16 and the normal (divide by 1) baud
rate generator prescaler respectively.  This is the rate that is divided
by the value held in the divisor latch to determine the baud rate used.

Replace the incorrect baud base of 4000000 with the right value of
3906250 then.

References:

[1] "OXPCIe200 PCI Express Multi-Port Bridge", Oxford Semiconductor,
    Inc., DS-0045, 10 Nov 2008, Section "Reset Configuration", p. 72

[2] "OXPCIe952 PCI Express Bridge to Dual Serial & Parallel Port",
    Oxford Semiconductor, Inc., DS-0046, Mar 06 08, Section "Reset
    Configuration", p. 27

[3] "OXPCIe954 PCI Express Bridge to Quad Serial Port", Oxford
    Semiconductor, Inc., DS-0047, Feb 08, Section "Reset Configuration",
    p. 28

[4] "OXPCIe958 PCI Express Bridge to Octal Serial Port", Oxford
    Semiconductor, Inc., DS-0048, Feb 08, Section "Reset Configuration",
    p. 28

Fixes: 7106b4e333bae ("8250: Oxford Semiconductor Devices")
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2106100203510.5469@angie.orcam.me.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-21 15:16:19 +02:00
Maciej W. Rozycki
3e9baedb32 serial: 8250: Dissociate 4MHz Titan ports from Oxford ports
[ Upstream commit f771a34b141124a68265f91acae34cdb08aeb9e0 ]

Oxford Semiconductor PCIe (Tornado) serial port devices have their baud
base set incorrectly, however their `pciserial_board' entries have been
reused for Titan serial port devices.  Define own entries for the latter
devices then, carrying over the settings, so that Oxford entries can be
fixed.

Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2106100142310.5469@angie.orcam.me.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-21 15:16:19 +02:00
Daniel Starke
8fd063a608 tty: n_gsm: fix missing corner cases in gsmld_poll()
[ Upstream commit 7e5b4322cde067e1d0f1bf8f490e93f664a7c843 ]

gsmld_poll() currently fails to handle the following corner cases correctly:
- remote party closed the associated tty

Add the missing checks and map those to EPOLLHUP.
Reorder the checks to group them by their reaction.

Fixes: e1eaea46bb40 ("tty: n_gsm line discipline")
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220707113223.3685-4-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-21 15:16:08 +02:00
Daniel Starke
01c8094bed tty: n_gsm: fix DM command
[ Upstream commit 18a948c7d90995d127785e308fa7b701df4c499f ]

n_gsm is based on the 3GPP 07.010 and its newer version is the 3GPP 27.010.
See https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=1516
The changes from 07.010 to 27.010 are non-functional. Therefore, I refer to
the newer 27.010 here. Chapter 5.3.3 defines the DM response. There exists
no DM command. However, the current implementation incorrectly sends DM as
command in case of unexpected UIH frames in gsm_queue().
Correct this behavior by always sending DM as response.

Fixes: e1eaea46bb40 ("tty: n_gsm line discipline")
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220707113223.3685-2-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-21 15:16:08 +02:00
Daniel Starke
6737d4f5f5 tty: n_gsm: fix wrong T1 retry count handling
[ Upstream commit f30e10caa80aa1f35508bc17fc302dbbde9a833c ]

n_gsm is based on the 3GPP 07.010 and its newer version is the 3GPP 27.010.
See https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=1516
The changes from 07.010 to 27.010 are non-functional. Therefore, I refer to
the newer 27.010 here. Chapter 5.7.3 states that the valid range for the
maximum number of retransmissions (N2) is from 0 to 255 (both including).
gsm_dlci_t1() handles this number incorrectly by performing N2 - 1
retransmission attempts. Setting N2 to zero results in more than 255
retransmission attempts.
Fix gsm_dlci_t1() to comply with 3GPP 27.010.

Fixes: e1eaea46bb40 ("tty: n_gsm line discipline")
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220707113223.3685-1-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-21 15:16:08 +02:00
Daniel Starke
273d412177 tty: n_gsm: fix race condition in gsmld_write()
[ Upstream commit 32dd59f96924f45e33bc79854f7a00679c0fa28e ]

The function may be used by the user directly and also by the n_gsm
internal functions. They can lead into a race condition which results in
interleaved frames if both are writing at the same time. The receiving side
is not able to decode those interleaved frames correctly.

Add a lock around the low side tty write to avoid race conditions and frame
interleaving between user originated writes and n_gsm writes.

Fixes: e1eaea46bb40 ("tty: n_gsm line discipline")
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220701061652.39604-9-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-21 15:16:07 +02:00
Daniel Starke
2466486cae tty: n_gsm: fix packet re-transmission without open control channel
[ Upstream commit 4fae831b3a71fc5a44cc5c7d0b8c1267ee7659f5 ]

In the current implementation control packets are re-transmitted even if
the control channel closed down during T2. This is wrong.
Check whether the control channel is open before re-transmitting any
packets. Note that control channel open/close is handled by T1 and not T2
and remains unaffected by this.

Fixes: e1eaea46bb40 ("tty: n_gsm line discipline")
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220701061652.39604-7-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-21 15:16:06 +02:00
Daniel Starke
34c9fe392d tty: n_gsm: fix non flow control frames during mux flow off
[ Upstream commit bec0224816d19abe4fe503586d16d51890540615 ]

n_gsm is based on the 3GPP 07.010 and its newer version is the 3GPP 27.010.
See https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=1516
The changes from 07.010 to 27.010 are non-functional. Therefore, I refer to
the newer 27.010 here. Chapter 5.4.6.3.6 states that FCoff stops the
transmission on all channels except the control channel. This is already
implemented in gsm_data_kick(). However, chapter 5.4.8.1 explains that this
shall result in the same behavior as software flow control on the ldisc in
advanced option mode. That means only flow control frames shall be sent
during flow off. The current implementation does not consider this case.

Change gsm_data_kick() to send only flow control frames if constipated to
abide the standard. gsm_read_ea_val() and gsm_is_flow_ctrl_msg() are
introduced as helper functions for this.
It is planned to use gsm_read_ea_val() in later code cleanups for other
functions, too.

Fixes: c01af4fec2c8 ("n_gsm : Flow control handling in Mux driver")
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220701061652.39604-5-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-21 15:16:06 +02:00
Daniel Starke
006e9d5a98 tty: n_gsm: fix wrong queuing behavior in gsm_dlci_data_output()
[ Upstream commit 556fc8ac06513cced381588d6d58c184d95cc4fe ]

1) The function drains the fifo for the given user tty/DLCI without
considering 'TX_THRESH_HI' and different to gsm_dlci_data_output_framed(),
which moves only one packet from the user side to the internal transmission
queue. We can only handle one packet at a time here if we want to allow
DLCI priority handling in gsm_dlci_data_sweep() to avoid link starvation.
2) Furthermore, the additional header octet from convergence layer type 2
is not counted against MTU. It is part of the UI/UIH frame message which
needs to be limited to MTU. Hence, it is wrong not to consider this octet.
3) Finally, the waiting user tty is not informed about freed space in its
send queue.

Take at most one packet worth of data out of the DLCI fifo to fix 1).
Limit the max user data size per packet to MTU - 1 in case of convergence
layer type 2 to leave space for the control signal octet which is added in
the later part of the function. This fixes 2).
Add tty_port_tty_wakeup() to wake up the user tty if new write space has
been made available to fix 3).

Fixes: 268e526b935e ("tty/n_gsm: avoid fifo overflow in gsm_dlci_data_output")
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220701061652.39604-3-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-21 15:16:06 +02:00
Daniel Starke
c45b5d24fe tty: n_gsm: fix user open not possible at responder until initiator open
[ Upstream commit ac77f0077c3265197d378158c85a55eee6d21508 ]

After setting up the control channel on both sides the responder side may
want to open a virtual tty to listen on until the initiator starts an
application on a user channel. The current implementation allows the
open() but no other operation, like termios. These fail with EINVAL.
The responder sided application has no means to detect an open by the
initiator sided application this way. And the initiator sided applications
usually expect the responder sided application to listen on the user
channel upon open.
Set the user channel into half-open state on responder side once a user
application opens the virtual tty to allow IO operations on it.
Furthermore, keep the user channel constipated until the initiator side
opens it to give the responder sided application the chance to detect the
new connection and to avoid data loss if the responder sided application
starts sending before the user channel is open.

Fixes: e1eaea46bb40 ("tty: n_gsm line discipline")
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220701061652.39604-1-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-21 15:16:06 +02:00
Zhenguo Zhao
9e38020f17 tty: n_gsm: Delete gsmtty open SABM frame when config requester
[ Upstream commit cbff2b32516881bef30bbebf413d1b49495bab1d ]

When n_gsm config "initiator=0",as requester ,it doesn't need to
send SABM frame data during gsmtty open.

Example,when gsmtty open,it will send SABM frame.for initiator,it
maybe not want to receive the frame.

[   88.410426] c1 gsmld_output: 00000000: f9 07 3f 01 de f9
[   88.420839] c1 --> 1) R: SABM(F)

Signed-off-by: Zhenguo Zhao <Zhenguo.Zhao1@unisoc.com>
Link: https://lore.kernel.org/r/1629461872-26965-6-git-send-email-zhenguo6858@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-21 15:16:06 +02:00
Ilpo Järvinen
4b171ac88c serial: 8250_dw: Store LSR into lsr_saved_flags in dw8250_tx_wait_empty()
[ Upstream commit af14f3007e2dca0d112f10f6717ba43093f74e81 ]

Make sure LSR flags are preserved in dw8250_tx_wait_empty(). This
function is called from a low-level out function and therefore cannot
call serial_lsr_in() as it would lead to infinite recursion.

It is borderline if the flags need to be saved here at all since this
code relates to writing LCR register which usually implies no important
characters should be arriving.

Fixes: 914eaf935ec7 ("serial: 8250_dw: Allow TX FIFO to drain before writing to UART_LCR")
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220608095431.18376-7-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-21 15:16:05 +02:00