Commit graph

4,752 commits

Author SHA1 Message Date
Johan Hovold
282c9eeda6 serial: stm32: fix threaded interrupt handling
[ Upstream commit e359b4411c ]

When DMA is enabled the receive handler runs in a threaded handler, but
the primary handler up until very recently neither disabled interrupts
in the device or used IRQF_ONESHOT. This would lead to a deadlock if an
interrupt comes in while the threaded receive handler is running under
the port lock.

Commit ad76768124 ("serial: stm32: fix a deadlock condition with
wakeup event") claimed to fix an unrelated deadlock, but unfortunately
also disabled interrupts in the threaded handler. While this prevents
the deadlock mentioned in the previous paragraph it also defeats the
purpose of using a threaded handler in the first place.

Fix this by making the interrupt one-shot and not disabling interrupts
in the threaded handler.

Note that (receive) DMA must not be used for a console port as the
threaded handler could be interrupted while holding the port lock,
something which could lead to a deadlock in case an interrupt handler
ends up calling printk.

Fixes: ad76768124 ("serial: stm32: fix a deadlock condition with wakeup event")
Fixes: 3489187204 ("serial: stm32: adding dma support")
Cc: stable@vger.kernel.org      # 4.9
Cc: Alexandre TORGUE <alexandre.torgue@st.com>
Cc: Gerald Baeza <gerald.baeza@st.com>
Reviewed-by: Valentin Caron<valentin.caron@foss.st.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20210416140557.25177-3-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-06-10 13:39:22 +02:00
Atul Gopinathan
52610c1d25 serial: max310x: unregister uart driver in case of failure and abort
[ Upstream commit 3890e3dea3 ]

The macro "spi_register_driver" invokes the function
"__spi_register_driver()" which has a return type of int and can fail,
returning a negative value in such a case. This is currently ignored and
the init() function yields success even if the spi driver failed to
register.

Fix this by collecting the return value of "__spi_register_driver()" and
also unregister the uart driver in case of failure.

Cc: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Atul Gopinathan <atulgopinathan@gmail.com>
Link: https://lore.kernel.org/r/20210503115736.2104747-12-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-06-03 09:00:40 +02:00
Greg Kroah-Hartman
f7d0b8542f Revert "serial: max310x: pass return value of spi_register_driver"
[ Upstream commit b0a85abbe9 ]

This reverts commit 51f689cc11.

Because of recent interactions with developers from @umn.edu, all
commits from them have been recently re-reviewed to ensure if they were
correct or not.

Upon review, this commit was found to be incorrect for the reasons
below, so it must be reverted.  It will be fixed up "correctly" in a
later kernel change.

This change did not properly unwind from the error condition, so it was
not correct.

Cc: Kangjie Lu <kjlu@umn.edu>
Acked-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20210503115736.2104747-11-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-06-03 09:00:40 +02:00
Zheyu Ma
6a931ceb0b serial: rp2: use 'request_firmware' instead of 'request_firmware_nowait'
commit 016002848c upstream.

In 'rp2_probe', the driver registers 'rp2_uart_interrupt' then calls
'rp2_fw_cb' through 'request_firmware_nowait'. In 'rp2_fw_cb', if the
firmware don't exists, function just return without initializing ports
of 'rp2_card'. But now the interrupt handler function has been
registered, and when an interrupt comes, 'rp2_uart_interrupt' may access
those ports then causing NULL pointer dereference or other bugs.

Because the driver does some initialization work in 'rp2_fw_cb', in
order to make the driver ready to handle interrupts, 'request_firmware'
should be used instead of asynchronous 'request_firmware_nowait'.

This report reveals it:

INFO: trying to register non-static key.
the code is fine but needs lockdep annotation.
turning off the locking correctness validator.
CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.19.177-gdba4159c14ef-dirty #45
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-
gc9ba5276e321-prebuilt.qemu.org 04/01/2014
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0xec/0x156 lib/dump_stack.c:118
 assign_lock_key kernel/locking/lockdep.c:727 [inline]
 register_lock_class+0x14e5/0x1ba0 kernel/locking/lockdep.c:753
 __lock_acquire+0x187/0x3750 kernel/locking/lockdep.c:3303
 lock_acquire+0x124/0x340 kernel/locking/lockdep.c:3907
 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
 _raw_spin_lock+0x32/0x50 kernel/locking/spinlock.c:144
 spin_lock include/linux/spinlock.h:329 [inline]
 rp2_ch_interrupt drivers/tty/serial/rp2.c:466 [inline]
 rp2_asic_interrupt.isra.9+0x15d/0x990 drivers/tty/serial/rp2.c:493
 rp2_uart_interrupt+0x49/0xe0 drivers/tty/serial/rp2.c:504
 __handle_irq_event_percpu+0xfb/0x770 kernel/irq/handle.c:149
 handle_irq_event_percpu+0x79/0x150 kernel/irq/handle.c:189
 handle_irq_event+0xac/0x140 kernel/irq/handle.c:206
 handle_fasteoi_irq+0x232/0x5c0 kernel/irq/chip.c:725
 generic_handle_irq_desc include/linux/irqdesc.h:155 [inline]
 handle_irq+0x230/0x3a0 arch/x86/kernel/irq_64.c:87
 do_IRQ+0xa7/0x1e0 arch/x86/kernel/irq.c:247
 common_interrupt+0xf/0xf arch/x86/entry/entry_64.S:670
 </IRQ>
RIP: 0010:native_safe_halt+0x28/0x30 arch/x86/include/asm/irqflags.h:61
Code: 00 00 55 be 04 00 00 00 48 c7 c7 00 c2 2f 8c 48 89 e5 e8 fb 31 e7 f8
8b 05 75 af 8d 03 85 c0 7e 07 0f 00 2d 8a 61 65 00 fb f4 <5d> c3 90 90 90
90 90 90 0f 1f 44 00 00 55 48 89 e5 41 57 41 56 41
RSP: 0018:ffff88806b71fcc8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffffde
RAX: 0000000000000000 RBX: ffffffff8bde7e48 RCX: ffffffff88a21285
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffff8c2fc200
RBP: ffff88806b71fcc8 R08: fffffbfff185f840 R09: fffffbfff185f840
R10: 0000000000000001 R11: fffffbfff185f840 R12: 0000000000000002
R13: ffffffff8bea18a0 R14: 0000000000000000 R15: 0000000000000000
 arch_safe_halt arch/x86/include/asm/paravirt.h:94 [inline]
 default_idle+0x6f/0x360 arch/x86/kernel/process.c:557
 arch_cpu_idle+0xf/0x20 arch/x86/kernel/process.c:548
 default_idle_call+0x3b/0x60 kernel/sched/idle.c:93
 cpuidle_idle_call kernel/sched/idle.c:153 [inline]
 do_idle+0x2ab/0x3c0 kernel/sched/idle.c:263
 cpu_startup_entry+0xcb/0xe0 kernel/sched/idle.c:369
 start_secondary+0x3b8/0x4e0 arch/x86/kernel/smpboot.c:271
 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243
BUG: unable to handle kernel NULL pointer dereference at 0000000000000010
PGD 8000000056d27067 P4D 8000000056d27067 PUD 56d28067 PMD 0
Oops: 0000 [#1] PREEMPT SMP KASAN PTI
CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.19.177-gdba4159c14ef-dirty #45
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-
gc9ba5276e321-prebuilt.qemu.org 04/01/2014
RIP: 0010:readl arch/x86/include/asm/io.h:59 [inline]
RIP: 0010:rp2_ch_interrupt drivers/tty/serial/rp2.c:472 [inline]
RIP: 0010:rp2_asic_interrupt.isra.9+0x181/0x990 drivers/tty/serial/rp2.c:
493
Code: df e8 43 5d c2 05 48 8d 83 e8 01 00 00 48 89 85 60 ff ff ff 48 c1 e8
03 42 80 3c 30 00 0f 85 aa 07 00 00 48 8b 83 e8 01 00 00 <8b> 40 10 89 c1
89 85 68 ff ff ff 48 8b 83 e8 01 00 00 89 48 10 83
RSP: 0018:ffff88806c287cd0 EFLAGS: 00010046
RAX: 0000000000000000 RBX: ffff88806ade6820 RCX: ffffffff814300b1
RDX: 1ffff1100d5bcd06 RSI: 0000000000000004 RDI: ffff88806ade6820
RBP: ffff88806c287db8 R08: ffffed100d5bcd05 R09: ffffed100d5bcd05
R10: 0000000000000001 R11: ffffed100d5bcd04 R12: ffffc90001e00000
R13: ffff888069654e10 R14: dffffc0000000000 R15: ffff888069654df0
FS:  0000000000000000(0000) GS:ffff88806c280000(0000) knlGS:
0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000010 CR3: 000000006892c000 CR4: 00000000000006e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 rp2_uart_interrupt+0x49/0xe0 drivers/tty/serial/rp2.c:504
 __handle_irq_event_percpu+0xfb/0x770 kernel/irq/handle.c:149
 handle_irq_event_percpu+0x79/0x150 kernel/irq/handle.c:189
 handle_irq_event+0xac/0x140 kernel/irq/handle.c:206
 handle_fasteoi_irq+0x232/0x5c0 kernel/irq/chip.c:725
 generic_handle_irq_desc include/linux/irqdesc.h:155 [inline]
 handle_irq+0x230/0x3a0 arch/x86/kernel/irq_64.c:87
 do_IRQ+0xa7/0x1e0 arch/x86/kernel/irq.c:247
 common_interrupt+0xf/0xf arch/x86/entry/entry_64.S:670
 </IRQ>
RIP: 0010:native_safe_halt+0x28/0x30 arch/x86/include/asm/irqflags.h:61
Code: 00 00 55 be 04 00 00 00 48 c7 c7 00 c2 2f 8c 48 89 e5 e8 fb 31 e7
f8 8b 05 75 af 8d 03 85 c0 7e 07 0f 00 2d 8a 61 65 00 fb f4 <5d> c3 90
90 90 90 90 90 0f 1f 44 00 00 55 48 89 e5 41 57 41 56 41
RSP: 0018:ffff88806b71fcc8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffffde
RAX: 0000000000000000 RBX: ffffffff8bde7e48 RCX: ffffffff88a21285
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffff8c2fc200
RBP: ffff88806b71fcc8 R08: fffffbfff185f840 R09: fffffbfff185f840
R10: 0000000000000001 R11: fffffbfff185f840 R12: 0000000000000002
R13: ffffffff8bea18a0 R14: 0000000000000000 R15: 0000000000000000
 arch_safe_halt arch/x86/include/asm/paravirt.h:94 [inline]
 default_idle+0x6f/0x360 arch/x86/kernel/process.c:557
 arch_cpu_idle+0xf/0x20 arch/x86/kernel/process.c:548
 default_idle_call+0x3b/0x60 kernel/sched/idle.c:93
 cpuidle_idle_call kernel/sched/idle.c:153 [inline]
 do_idle+0x2ab/0x3c0 kernel/sched/idle.c:263
 cpu_startup_entry+0xcb/0xe0 kernel/sched/idle.c:369
 start_secondary+0x3b8/0x4e0 arch/x86/kernel/smpboot.c:271
 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243
Modules linked in:
Dumping ftrace buffer:
   (ftrace buffer empty)
CR2: 0000000000000010
---[ end trace 11804dbb55cb1a64 ]---
RIP: 0010:readl arch/x86/include/asm/io.h:59 [inline]
RIP: 0010:rp2_ch_interrupt drivers/tty/serial/rp2.c:472 [inline]
RIP: 0010:rp2_asic_interrupt.isra.9+0x181/0x990 drivers/tty/serial/rp2.c:
493
Code: df e8 43 5d c2 05 48 8d 83 e8 01 00 00 48 89 85 60 ff ff ff 48 c1
e8 03 42 80 3c 30 00 0f 85 aa 07 00 00 48 8b 83 e8 01 00 00 <8b> 40 10 89
c1 89 85 68 ff ff ff 48 8b 83 e8 01 00 00 89 48 10 83
RSP: 0018:ffff88806c287cd0 EFLAGS: 00010046
RAX: 0000000000000000 RBX: ffff88806ade6820 RCX: ffffffff814300b1
RDX: 1ffff1100d5bcd06 RSI: 0000000000000004 RDI: ffff88806ade6820
RBP: ffff88806c287db8 R08: ffffed100d5bcd05 R09: ffffed100d5bcd05
R10: 0000000000000001 R11: ffffed100d5bcd04 R12: ffffc90001e00000
R13: ffff888069654e10 R14: dffffc0000000000 R15: ffff888069654df0
FS:  0000000000000000(0000) GS:ffff88806c280000(0000) knlGS:
0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000010 CR3: 000000006892c000 CR4: 00000000000006e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Reported-by: Zheyu Ma <zheyuma97@gmail.com>
Signed-off-by: Zheyu Ma <zheyuma97@gmail.com>
Link: https://lore.kernel.org/r/1621577323-1541-1-git-send-email-zheyuma97@gmail.com
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-06-03 09:00:34 +02:00
Geert Uytterhoeven
e955711701 serial: sh-sci: Fix off-by-one error in FIFO threshold register setting
commit 2ea2e019c1 upstream.

The Receive FIFO Data Count Trigger field (RTRG[6:0]) in the Receive
FIFO Data Count Trigger Register (HSRTRGR) of HSCIF can only hold values
ranging from 0-127.  As the FIFO size is equal to 128 on HSCIF, the user
can write an out-of-range value, touching reserved bits.

Fix this by limiting the trigger value to the FIFO size minus one.
Reverse the order of the checks, to avoid rx_trig becoming zero if the
FIFO size is one.

Note that this change has no impact on other SCIF variants, as their
maximum supported trigger value is lower than the FIFO size anyway, and
the code below takes care of enforcing these limits.

Fixes: a380ed461f ("serial: sh-sci: implement FIFO threshold register setting")
Reported-by: Linh Phung <linh.phung.jy@renesas.com>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Ulrich Hecht <uli+renesas@fpond.eu>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/5eff320aef92ffb33d00e57979fd3603bbb4a70f.1620648218.git.geert+renesas@glider.be
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-06-03 09:00:34 +02:00
Colin Ian King
604c654323 serial: tegra: Fix a mask operation that is always true
commit 3ddb4ce1e6 upstream.

Currently the expression lsr | UART_LSR_TEMT is always true and
this seems suspect. I believe the intent was to mask lsr with UART_LSR_TEMT
to check that bit, so the expression should be using the & operator
instead. Fix this.

Fixes: b9c2470fb1 ("serial: tegra: flush the RX fifo on frame error")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20210426105514.23268-1-colin.king@canonical.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-06-03 09:00:34 +02:00
Christian Gmeiner
ae46660bf2 serial: 8250_pci: handle FL_NOIRQ board flag
commit 9808f9be31 upstream.

In commit 8428413b1d ("serial: 8250_pci: Implement MSI(-X) support")
the way the irq gets allocated was changed. With that change the
handling FL_NOIRQ got lost. Restore the old behaviour.

Fixes: 8428413b1d ("serial: 8250_pci: Implement MSI(-X) support")
Cc: <stable@vger.kernel.org>
Signed-off-by: Christian Gmeiner <christian.gmeiner@gmail.com>
Link: https://lore.kernel.org/r/20210527095529.26281-1-christian.gmeiner@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-06-03 09:00:34 +02:00
Randy Wright
60f9e33bb7 serial: 8250_pci: Add support for new HPE serial device
commit e0e2420879 upstream.

Add support for new HPE serial device.  It is MSI enabled,
but otherwise similar to legacy HP server serial devices.

Tested-by: Jerry Hoemann <jerry.hoemann@hpe.com>
Signed-off-by: Randy Wright <rwright@hpe.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/1621009614-28836-1-git-send-email-rwright@hpe.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-06-03 09:00:33 +02:00
Maximilian Luz
a4a261328c serial: 8250_dw: Add device HID for new AMD UART controller
commit 3c35d2a960 upstream.

Add device HID AMDI0022 to the AMD UART controller driver match table
and create a platform device for it. This controller can be found on
Microsoft Surface Laptop 4 devices and seems similar enough that we can
just copy the existing AMDI0020 entries.

Cc: <stable@vger.kernel.org> # 5.10+
Tested-by: Sachi King <nakato@nakato.io>
Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com> # for 8250_dw part
Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20210512210413.1982933-1-luzmaximilian@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-06-03 09:00:33 +02:00
Andrew Jeffery
595505fc6f serial: 8250: Add UART_BUG_TXRACE workaround for Aspeed VUART
commit df8f2be2fd upstream.

Aspeed Virtual UARTs directly bridge e.g. the system console UART on the
LPC bus to the UART interface on the BMC's internal APB. As such there's
no RS-232 signalling involved - the UART interfaces on each bus are
directly connected as the producers and consumers of the one set of
FIFOs.

The APB in the AST2600 generally runs at 100MHz while the LPC bus peaks
at 33MHz. The difference in clock speeds exposes a race in the VUART
design where a Tx data burst on the APB interface can result in a byte
lost on the LPC interface. The symptom is LSR[DR] remains clear on the
LPC interface despite data being present in its Rx FIFO, while LSR[THRE]
remains clear on the APB interface as the host has not consumed the data
the BMC has transmitted. In this state, the UART has stalled and no
further data can be transmitted without manual intervention (e.g.
resetting the FIFOs, resulting in loss of data).

The recommended work-around is to insert a read cycle on the APB
interface between writes to THR.

Cc: ChiaWei Wang <chiawei_wang@aspeedtech.com>
Tested-by: ChiaWei Wang <chiawei_wang@aspeedtech.com>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20210520021334.497341-2-andrew@aj.id.au
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-06-03 09:00:33 +02:00
Ondrej Mosnacek
1a2494c9eb serial: core: fix suspicious security_locked_down() call
commit 5e722b217a upstream.

The commit that added this check did so in a very strange way - first
security_locked_down() is called, its value stored into retval, and if
it's nonzero, then an additional check is made for (change_irq ||
change_port), and if this is true, the function returns. However, if
the goto exit branch is not taken, the code keeps the retval value and
continues executing the function. Then, depending on whether
uport->ops->verify_port is set, the retval value may or may not be reset
to zero and eventually the error value from security_locked_down() may
abort the function a few lines below.

I will go out on a limb and assume that this isn't the intended behavior
and that an error value from security_locked_down() was supposed to
abort the function only in case (change_irq || change_port) is true.

Note that security_locked_down() should be called last in any series of
checks, since the SELinux implementation of this hook will do a check
against the policy and generate an audit record in case of denial. If
the operation was to carry on after calling security_locked_down(), then
the SELinux denial record would be bogus.

See commit 59438b4647 ("security,lockdown,selinux: implement SELinux
lockdown") for how SELinux implements this hook.

Fixes: 794edf30ee ("lockdown: Lock down TIOCSSERIAL")
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20210507115719.140799-1-omosnace@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-06-03 09:00:32 +02:00
Greg Kroah-Hartman
e4be684653 Revert "serial: mvebu-uart: Fix to avoid a potential NULL pointer dereference"
commit 754f391584 upstream.

This reverts commit 32f4717983.

Because of recent interactions with developers from @umn.edu, all
commits from them have been recently re-reviewed to ensure if they were
correct or not.

Upon review, this commit was found to be not be needed at all as the
change was useless because this function can only be called when
of_match_device matched on something.  So it should be reverted.

Cc: Aditya Pakki <pakki001@umn.edu>
Cc: stable <stable@vger.kernel.org>
Fixes: 32f4717983 ("serial: mvebu-uart: Fix to avoid a potential NULL pointer dereference")
Acked-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20210503115736.2104747-6-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-26 12:06:52 +02:00
Dario Binacchi
565e7c98d3 serial: omap: fix rs485 half-duplex filtering
[ Upstream commit e2a5e8448e ]

Data received during half-duplex transmission must be filtered.
If the target device responds quickly, emptying the FIFO at the end of
the transmission can erase not only the echo characters but also part of
the response message.
By keeping the receive interrupt enabled even during transmission, it
allows you to filter each echo character and only in a number equal to
those transmitted.
The issue was generated by a target device that started responding
240us later having received a request in communication at 115200bps.
Sometimes, some messages received by the target were missing some of the
first bytes.

Fixes: 3a13884abe ("tty/serial: omap: empty the RX FIFO at the end of half-duplex TX")
Signed-off-by: Dario Binacchi <dariobin@libero.it>
Link: https://lore.kernel.org/r/20210418094705.27014-1-dariobin@libero.it
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-14 09:50:21 +02:00
Dario Binacchi
9c3e2ad20b serial: omap: don't disable rs485 if rts gpio is missing
[ Upstream commit 45f6b6db53 ]

There are rs485 transceivers (e.g. MAX13487E/MAX13488E) which
automatically disable or enable the driver and receiver to keep the bus
in the correct state.
In these cases we don't need a GPIO for flow control.

Fixes: 4a0ac0f55b ("OMAP: add RS485 support")
Signed-off-by: Dario Binacchi <dariobin@libero.it>
Link: https://lore.kernel.org/r/20210415210945.25863-1-dariobin@libero.it
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-14 09:50:21 +02:00
Johan Hovold
26882a15ed serial: core: return early on unsupported ioctls
[ Upstream commit 79c5966cec ]

Drivers can return -ENOIOCTLCMD when an ioctl is not recognised to tell
the upper layers to continue looking for a handler.

This is not the case for the RS485 and ISO7816 ioctls whose handlers
should return -ENOTTY directly in case a serial driver does not
implement the corresponding methods.

Fixes: a5f276f10f ("serial_core: Handle TIOC[GS]RS485 ioctls.")
Fixes: ad8c0eaa0a ("tty/serial_core: add ISO7816 infrastructure")
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20210407095208.31838-9-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-14 09:50:19 +02:00
Erwan Le Ray
98743f2b8c serial: stm32: fix tx_empty condition
[ Upstream commit 3db1d52466 ]

In "tx_empty", we should poll TC bit in both DMA and PIO modes (instead of
TXE) to check transmission data register has been transmitted independently
of the FIFO mode. TC indicates that both transmit register and shift
register are empty. When shift register is empty, tx_empty should return
TIOCSER_TEMT instead of TC value.

Cleans the USART_CR_TC TCCF register define (transmission complete clear
flag) as it is duplicate of USART_ICR_TCCF.

Fixes: 48a6092fb4 ("serial: stm32-usart: Add STM32 USART Driver")
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Link: https://lore.kernel.org/r/20210304162308.8984-13-erwan.leray@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-14 09:50:08 +02:00
Erwan Le Ray
566901ba50 serial: stm32: add FIFO flush when port is closed
[ Upstream commit 9f77d19207 ]

Transmission complete error is sent when ISR_TC is not set. If port closure
is requested despite data in TDR / TX FIFO has not been sent (because of
flow control), ISR_TC is not set and error message is sent on port closure
but also when a new port is opened.

Flush the data when port is closed, so the error isn't printed twice upon
next port opening.

Fixes: 64c32eab66 ("serial: stm32: Add support of TC bit status check")
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Link: https://lore.kernel.org/r/20210304162308.8984-12-erwan.leray@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-14 09:50:08 +02:00
Erwan Le Ray
01ce9c5d17 serial: stm32: fix FIFO flush in startup and set_termios
[ Upstream commit 315e2d8a12 ]

Fifo flush set USART_RQR register by calling stm32_usart_set_bits
routine (Read/Modify/Write). USART_RQR register is a write only
register. So, read before write isn't correct / relevant to flush
the FIFOs.
Replace stm32_usart_set_bits call by writel_relaxed.

Fixes: 84872dc448 ("serial: stm32: add RX and TX FIFO flush")
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Link: https://lore.kernel.org/r/20210304162308.8984-11-erwan.leray@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-14 09:50:08 +02:00
Erwan Le Ray
f765918b33 serial: stm32: call stm32_transmit_chars locked
[ Upstream commit f16b90c2d9 ]

stm32_transmit_chars should be called under lock also in tx DMA callback.

Fixes: 3489187204 ("serial: stm32: adding dma support")
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@foss.st.com>
Link: https://lore.kernel.org/r/20210304162308.8984-10-erwan.leray@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-14 09:50:08 +02:00
Erwan Le Ray
a98c0683a3 serial: stm32: fix tx dma completion, release channel
[ Upstream commit fb4f2e04ac ]

This patch add a proper release of dma channels when completing dma tx.

Fixes: 3489187204 ("serial: stm32: adding dma support")
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Link: https://lore.kernel.org/r/20210304162308.8984-9-erwan.leray@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-14 09:50:08 +02:00
Erwan Le Ray
1f308f65d8 serial: stm32: fix a deadlock in set_termios
[ Upstream commit 436c979360 ]

CTS/RTS GPIOs support that has been added recently to STM32 UART driver has
introduced scheduled code in a set_termios part protected by a spin lock.
This generates a potential deadlock scenario:

Chain exists of:
&irq_desc_lock_class --> console_owner --> &port_lock_key

Possible unsafe locking scenario:

     CPU0                    CPU1
     ----                    ----
lock(&port_lock_key);
                           lock(console_owner);
                           lock(&port_lock_key);
lock(&irq_desc_lock_class);

*** DEADLOCK ***
4 locks held by stty/766:

Move the scheduled code after the spinlock.

Fixes: 6cf61b9bd7 ("tty: serial: Add modem control gpio support for STM32 UART")
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Link: https://lore.kernel.org/r/20210304162308.8984-8-erwan.leray@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-14 09:50:08 +02:00
Erwan Le Ray
5eacd7fa40 serial: stm32: fix wake-up flag handling
[ Upstream commit 12761869f0 ]

This patch fixes several issue with wake-up handling:
- the WUF irq is handled several times at wake-up
- the USART is disabled / enabled at suspend to set wake-up flag.
It can cause glitches during RX.

This patch fix those issues:
- clear wake-up flag and disable wake-up irq in WUF irq handling
- enable wake-up from low power on start bit detection at port
configuration
- Unmask the wake-up flag irq at suspend and mask it at resume

In addition, pm_wakeup_event handling is moved from receice_chars to WUF
irq handling.

Fixes: 270e5a74fe ("serial: stm32: add wakeup mechanism")
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Link: https://lore.kernel.org/r/20210304162308.8984-7-erwan.leray@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-14 09:50:08 +02:00
Erwan Le Ray
ea627af3dd serial: stm32: fix a deadlock condition with wakeup event
[ Upstream commit ad76768124 ]

Deadlock issue is seen when enabling CONFIG_PROVE_LOCKING=Y, and uart
console as wakeup source. Deadlock occurs when resuming from low power
mode if system is waked up via usart console.
The deadlock is triggered 100% when also disabling console suspend prior
to go to suspend.

Simplified call stack, deadlock condition:
- stm32_console_write <-- spin_lock already held
- print_circular_bug
- pm_wakeup_dev_event <-- triggers lockdep as seen above
- stm32_receive_chars
- stm32_interrupt <-- wakeup via uart console, takes the lock

So, revisit spin_lock in stm32-usart driver:
- there is no need to hold the lock to access ICR (atomic clear of status
  flags)
- only hold the lock inside stm32_receive_chars() routine (no need to
  call pm_wakeup_dev_event with lock held)
- keep stm32_transmit_chars() routine called with lock held

Fixes: 48a6092fb4 ("serial: stm32-usart: Add STM32 USART Driver")
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@foss.st.com>
Link: https://lore.kernel.org/r/20210304162308.8984-6-erwan.leray@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-14 09:50:08 +02:00
Erwan Le Ray
69ac7b3b89 serial: stm32: fix TX and RX FIFO thresholds
[ Upstream commit 25a8e7611d ]

TX and RX FIFO thresholds may be cleared after suspend/resume, depending
on the low power mode.

Those configurations (done in startup) are not effective for UART console,
as:
- the reference manual indicates that FIFOEN bit can only be written when
  the USART is disabled (UE=0)
- a set_termios (where UE is set) is requested firstly for console
  enabling, before the startup.

Fixes: 84872dc448 ("serial: stm32: add RX and TX FIFO flush")
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Link: https://lore.kernel.org/r/20210304162308.8984-5-erwan.leray@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-14 09:50:08 +02:00
Erwan Le Ray
5ca0d5b2c8 serial: stm32: fix incorrect characters on console
[ Upstream commit f264c6f6ae ]

Incorrect characters are observed on console during boot. This issue occurs
when init/main.c is modifying termios settings to open /dev/console on the
rootfs.

This patch adds a waiting loop in set_termios to wait for TX shift register
empty (and TX FIFO if any) before stopping serial port.

Fixes: 48a6092fb4 ("serial: stm32-usart: Add STM32 USART Driver")
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Link: https://lore.kernel.org/r/20210304162308.8984-4-erwan.leray@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-14 09:50:07 +02:00
Erwan Le Ray
a44d6acfa7 serial: stm32: fix startup by enabling usart for reception
[ Upstream commit f4518a8a75 ]

RX is configured, but usart is not enabled in startup function.
Kernel documentation specifies that startup should enable the port for
reception.
Fix the startup by enabling usart for reception.

Fixes: 84872dc448 ("serial: stm32: add RX and TX FIFO flush")
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Link: https://lore.kernel.org/r/20210304162308.8984-3-erwan.leray@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-14 09:50:07 +02:00
Stephen Boyd
b5e8f0adae serial: stm32: Use of_device_get_match_data()
[ Upstream commit d825f0bea2 ]

This driver casts away the constness of struct stm32_usart_info that is
pointed to by the of match table. Use of_device_get_match_data() instead
of of_match_device() here and push the const throughout the code so that
we don't cast away const. This nicely avoids referencing the match table
when it is undefined with configurations where CONFIG_OF=n and fixes the
const issues.

Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Frank Rowand <frowand.list@gmail.com>
Cc: <linux-serial@vger.kernel.org>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20210123034428.2841052-4-swboyd@chromium.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-14 09:50:07 +02:00
Erwan Le Ray
379b007b57 serial: stm32: fix probe and remove order for dma
[ Upstream commit 87fd0741d6 ]

The probe and remove orders are wrong as the uart_port is registered
before saving device data in the probe, and unregistered after DMA
resource deallocation in the remove. uart_port registering should be
done at the end of probe and unregistering should be done at the begin of
remove to avoid resource allocation issues.

Fix probe and remove orders. This enforce resource allocation occur at
proper time.
Terminate both DMA rx and tx transfers before removing device.

Move pm_runtime after uart_remove_one_port() call in remove() to keep the
probe error path.

Fixes: 3489187204 ("serial: stm32: adding dma support")
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Link: https://lore.kernel.org/r/20210304162308.8984-2-erwan.leray@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-14 09:50:07 +02:00
Erwan Le Ray
1027c8c028 serial: stm32: add "_usart" prefix in functions name
[ Upstream commit 56f9a76c27 ]

Adds the prefix "_usart" in the name of stm32 usart functions in order to
ease the usage of kernel trace and tools, such as f-trace.
Allows to trace "stm32_usart_*" functions with f-trace. Without this patch,
all the driver functions needs to be added manually in f-trace filter.

Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Link: https://lore.kernel.org/r/20210106162203.28854-4-erwan.leray@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-14 09:50:07 +02:00
Erwan Le Ray
ab8363f13f serial: stm32: fix code cleaning warnings and checks
[ Upstream commit 92fc002386 ]

Fixes checkpatch --strict warnings and checks:
- checkpatch --strict "Unnecessary parentheses"
- checkpatch --strict "Blank lines aren't necessary before a close brace
- checkpatch --strict "Alignment should match open parenthesis"
- checkpatch --strict "Please don't use multiple blank lines"
- checkpatch --strict "Comparison to NULL could be written ..."
- visual check code ordering warning

Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Link: https://lore.kernel.org/r/20210106162203.28854-3-erwan.leray@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-14 09:50:07 +02:00
Annaliese McDermond
66c86eefa2 sc16is7xx: Defer probe if device read fails
commit 158e800e0f upstream.

A test was added to the probe function to ensure the device was
actually connected and working before successfully completing a
probe.  If the device was actually there, but the I2C bus was not
ready yet for whatever reason, the probe fails permanently.

Change the probe so that we defer the probe on a regmap read
failure so that we try the probe again when the dependent drivers
are potentially loaded.  This should not affect the case where the
device truly isn't present because the probe will never successfully
complete.

Fixes: 2aa916e67d ("sc16is7xx: Read the LSR register for basic device presence check")
Cc: stable@vger.kernel.org
Signed-off-by: Annaliese McDermond <nh6z@nh6z.net>
Link: https://lore.kernel.org/r/010101787f9c3fd8-c1815c00-2d6b-4c85-a96a-a13e68597fda-000000@us-west-2.amazonses.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-14 09:49:58 +02:00
Roja Rani Yarubandi
84e5203fd2 soc: qcom-geni-se: Cleanup the code to remove proxy votes
commit 29d96eb261 upstream.

This reverts commit 048eb908a1 ("soc: qcom-geni-se: Add interconnect
support to fix earlycon crash")

ICC core and platforms drivers supports sync_state feature, which
ensures that the default ICC BW votes from the bootloader is not
removed until all it's consumers are probes.

The proxy votes were needed in case other QUP child drivers
I2C, SPI probes before UART, they can turn off the QUP-CORE clock
which is shared resources for all QUP driver, this causes unclocked
access to HW from earlycon.

Given above support from ICC there is no longer need to maintain
proxy votes on QUP-CORE ICC node from QUP wrapper driver for early
console usecase, the default votes won't be removed until real
console is probed.

Cc: stable@vger.kernel.org
Fixes: 266cd33b59 ("interconnect: qcom: Ensure that the floor bandwidth value is enforced")
Fixes: 7d3b0b0d81 ("interconnect: qcom: Use icc_sync_state")
Signed-off-by: Roja Rani Yarubandi <rojay@codeaurora.org>
Signed-off-by: Akash Asthana <akashast@codeaurora.org>
Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
Link: https://lore.kernel.org/r/20210324101836.25272-2-rojay@codeaurora.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-07 15:00:13 +02:00
Erwan Le Ray
0e44f1e183 serial: stm32: fix DMA initialization error handling
[ Upstream commit e7997f7ff7 ]

DMA initialization error handling is not properly implemented in the
driver.
Fix DMA initialization error handling by:
- moving TX DMA descriptor request error handling in a new dedicated
fallback_err label
- adding error handling to TX DMA descriptor submission
- adding error handling to RX DMA descriptor submission

This patch depends on '24832ca3ee ("tty: serial: stm32-usart: Remove set
but unused 'cookie' variables")' which unfortunately doesn't include a
"Fixes" tag.

Fixes: 3489187204 ("serial: stm32: adding dma support")
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Link: https://lore.kernel.org/r/20210106162203.28854-2-erwan.leray@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-25 09:04:10 +01:00
Lee Jones
5f8659adf7 tty: serial: stm32-usart: Remove set but unused 'cookie' variables
[ Upstream commit 24832ca3ee ]

Fixes the following W=1 kernel build warning(s):

 drivers/tty/serial/stm32-usart.c: In function ‘stm32_transmit_chars_dma’:
 drivers/tty/serial/stm32-usart.c:353:15: warning: variable ‘cookie’ set but not used [-Wunused-but-set-variable]
 drivers/tty/serial/stm32-usart.c: In function ‘stm32_of_dma_rx_probe’:
 drivers/tty/serial/stm32-usart.c:1090:15: warning: variable ‘cookie’ set but not used [-Wunused-but-set-variable]

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: Gerald Baeza <gerald.baeza@st.com>
Cc: linux-serial@vger.kernel.org
Cc: linux-stm32@st-md-mailman.stormreply.com
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20201104193549.4026187-29-lee.jones@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-25 09:04:10 +01:00
Alexander Shiyan
70c26fc71b Revert "serial: max310x: rework RX interrupt handling"
commit 2334de198f upstream.

This reverts commit fce3c5c1a2.

FIFO is triggered 4 intervals after receiving a byte, it's good
when we don't care about the time of reception, but are only
interested in the presence of any activity on the line.
Unfortunately, this method is not suitable for all tasks,
for example, the RS-485 protocol will not work properly,
since the state machine must track the request-response time
and after the timeout expires, a decision is made that the device
on the line is not responding.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Link: https://lore.kernel.org/r/20210217080608.31192-1-shc_work@mail.ru
Fixes: fce3c5c1a2 ("serial: max310x: rework RX interrupt handling")
Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-17 17:06:31 +01:00
Pali Rohár
ee3a62cb26 serial: mvebu-uart: fix tx lost characters at power off
commit 54ca955b5a upstream.

Commit c685af1108 ("serial: mvebu-uart: fix tx lost characters") fixed tx
lost characters at low baud rates but started causing tx lost characters
when kernel is going to power off or reboot.

TX_EMP tells us when transmit queue is empty therefore all characters were
transmitted. TX_RDY tells us when CPU can send a new character.

Therefore we need to use different check prior transmitting new character
and different check after all characters were sent.

This patch splits polling code into two functions: wait_for_xmitr() which
waits for TX_RDY and wait_for_xmite() which waits for TX_EMP.

When rebooting A3720 platform without this patch on UART is print only:
[   42.699�

And with this patch on UART is full output:
[   39.530216] reboot: Restarting system

Fixes: c685af1108 ("serial: mvebu-uart: fix tx lost characters")
Signed-off-by: Pali Rohár <pali@kernel.org>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20201223191931.18343-1-pali@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-27 11:55:16 +01:00
Damien Le Moal
094a4af043 riscv: Fix sifive serial driver
[ Upstream commit 1f1496a923 ]

Setup the port uartclk in sifive_serial_probe() so that the base baud
rate is correctly printed during device probe instead of always showing
"0".  I.e. the probe message is changed from

38000000.serial: ttySIF0 at MMIO 0x38000000 (irq = 1,
base_baud = 0) is a SiFive UART v0

to the correct:

38000000.serial: ttySIF0 at MMIO 0x38000000 (irq = 1,
base_baud = 115200) is a SiFive UART v0

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-01-27 11:54:59 +01:00
Finn Thain
29563a7381 m68k: Fix WARNING splat in pmac_zilog driver
commit a7b5458ce7 upstream.

Don't add platform resources that won't be used. This avoids a
recently-added warning from the driver core, that can show up on a
multi-platform kernel when !MACH_IS_MAC.

------------[ cut here ]------------
WARNING: CPU: 0 PID: 0 at drivers/base/platform.c:224 platform_get_irq_optional+0x8e/0xce
0 is an invalid IRQ number
Modules linked in:
CPU: 0 PID: 0 Comm: swapper Not tainted 5.9.0-multi #1
Stack from 004b3f04:
        004b3f04 00462c2f 00462c2f 004b3f20 0002e128 004754db 004b6ad4 004b3f4c
        0002e19c 004754f7 000000e0 00285ba0 00000009 00000000 004b3f44 ffffffff
        004754db 004b3f64 004b3f74 00285ba0 004754f7 000000e0 00000009 004754db
        004fdf0c 005269e2 004fdf0c 00000000 004b3f88 00285cae 004b6964 00000000
        004fdf0c 004b3fac 0051cc68 004b6964 00000000 004b6964 00000200 00000000
        0051cc3e 0023c18a 004b3fc0 0051cd8a 004fdf0c 00000002 0052b43c 004b3fc8
Call Trace: [<0002e128>] __warn+0xa6/0xd6
 [<0002e19c>] warn_slowpath_fmt+0x44/0x76
 [<00285ba0>] platform_get_irq_optional+0x8e/0xce
 [<00285ba0>] platform_get_irq_optional+0x8e/0xce
 [<00285cae>] platform_get_irq+0x12/0x4c
 [<0051cc68>] pmz_init_port+0x2a/0xa6
 [<0051cc3e>] pmz_init_port+0x0/0xa6
 [<0023c18a>] strlen+0x0/0x22
 [<0051cd8a>] pmz_probe+0x34/0x88
 [<0051cde6>] pmz_console_init+0x8/0x28
 [<00511776>] console_init+0x1e/0x28
 [<0005a3bc>] printk+0x0/0x16
 [<0050a8a6>] start_kernel+0x368/0x4ce
 [<005094f8>] _sinittext+0x4f8/0xc48
random: get_random_bytes called from print_oops_end_marker+0x56/0x80 with crng_init=0
---[ end trace 392d8e82eed68d6c ]---

Commit a85a6c86c2 ("driver core: platform: Clarify that IRQ 0 is invalid"),
which introduced the WARNING, suggests that testing for irq == 0 is
undesirable. Instead of that comparison, just test for resource existence.

Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Joshua Thompson <funaho@jurai.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: stable@vger.kernel.org # v5.8+
Reported-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Link: https://lore.kernel.org/r/0c0fe1e4f11ccec202d4df09ea7d9d98155d101a.1606001297.git.fthain@telegraphics.com.au
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-30 11:54:11 +01:00
Zhang Qilong
048a04aa03 serial: 8250-mtk: Fix reference leak in mtk8250_probe
[ Upstream commit 6e4e636e0e ]

The pm_runtime_enable will increase power disable depth.
Thus a pairing decrement is needed on the error handling
path to keep it balanced according to context.

Fixes: e32a83c70c ("serial: 8250-mtk: modify mtk uart power and clock management")
Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com>
Link: https://lore.kernel.org/r/20201119141126.168850-1-zhangqilong3@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-30 11:53:23 +01:00
Alexey Kardashevskiy
e6160ad6e7 serial_core: Check for port state when tty is in error state
commit 2f70e49ed8 upstream.

At the moment opening a serial device node (such as /dev/ttyS3)
succeeds even if there is no actual serial device behind it.
Reading/writing/ioctls fail as expected because the uart port is not
initialized (the type is PORT_UNKNOWN) and the TTY_IO_ERROR error state
bit is set fot the tty.

However setting line discipline does not have these checks
8250_port.c (8250 is the default choice made by univ8250_console_init()).
As the result of PORT_UNKNOWN, uart_port::iobase is NULL which
a platform translates onto some address accessing which produces a crash
like below.

This adds tty_port_initialized() to uart_set_ldisc() to prevent the crash.

Found by syzkaller.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Link: https://lore.kernel.org/r/20201203055834.45838-1-aik@ozlabs.ru
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-26 16:02:43 +01:00
Alexander Sverdlin
dadaf794f2 serial: 8250_omap: Avoid FIFO corruption caused by MDR1 access
commit d96f04d347 upstream.

It has been observed that once per 300-1300 port openings the first
transmitted byte is being corrupted on AM3352 ("v" written to FIFO appeared
as "e" on the wire). It only happened if single byte has been transmitted
right after port open, which means, DMA is not used for this transfer and
the corruption never happened afterwards.

Therefore I've carefully re-read the MDR1 errata (link below), which says
"when accessing the MDR1 registers that causes a dummy under-run condition
that will freeze the UART in IrDA transmission. In UART mode, this may
corrupt the transferred data". Strictly speaking,
omap_8250_mdr1_errataset() performs a read access and if the value is the
same as should be written, exits without errata-recommended FIFO reset.

A brief check of the serial_omap_mdr1_errataset() from the competing
omap-serial driver showed it has no read access of MDR1. After removing the
read access from omap_8250_mdr1_errataset() the data corruption never
happened any more.

Link: https://www.ti.com/lit/er/sprz360i/sprz360i.pdf
Fixes: 61929cf016 ("tty: serial: Add 8250-core based omap driver")
Cc: stable@vger.kernel.org
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@gmail.com>
Link: https://lore.kernel.org/r/20201210055257.1053028-1-alexander.sverdlin@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-21 13:30:08 +01:00
Zheng Zengkai
425af48352 serial: ar933x_uart: disable clk on error handling path in probe
ar933x_uart_probe() does not invoke clk_disable_unprepare()
on one error handling path. This patch fixes that.

Fixes: 9be1064fe5 ("serial: ar933x_uart: add RS485 support")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>
Link: https://lore.kernel.org/r/20201111124426.42638-1-zhengzengkai@huawei.com
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-12 09:41:07 +01:00
Fugang Duan
e67c139c48 tty: serial: imx: keep console clocks always on
For below code, there has chance to cause deadlock in SMP system:
Thread 1:
clk_enable_lock();
pr_info("debug message");
clk_enable_unlock();

Thread 2:
imx_uart_console_write()
	clk_enable()
		clk_enable_lock();

Thread 1:
Acuired clk enable_lock -> printk -> console_trylock_spinning
Thread 2:
console_unlock() -> imx_uart_console_write -> clk_disable -> Acquite clk enable_lock

So the patch is to keep console port clocks always on like
other console drivers.

Fixes: 1cf93e0d54 ("serial: imx: remove the uart_console() check")
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Fugang Duan <fugang.duan@nxp.com>
Link: https://lore.kernel.org/r/20201111025136.29818-1-fugang.duan@nxp.com
Cc: stable <stable@vger.kernel.org>
[fix up build warning - gregkh]
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-12 09:39:53 +01:00
Sam Nobs
33f16855dc tty: serial: imx: fix potential deadlock
Enabling the lock dependency validator has revealed
that the way spinlocks are used in the IMX serial
port could result in a deadlock.

Specifically, imx_uart_int() acquires a spinlock
without disabling the interrupts, meaning that another
interrupt could come along and try to acquire the same
spinlock, potentially causing the two to wait for each
other indefinitely.

Use spin_lock_irqsave() instead to disable interrupts
upon acquisition of the spinlock.

Fixes: c974991d26 ("tty:serial:imx: use spin_lock instead of spin_lock_irqsave in isr")
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Sam Nobs <samuel.nobs@taitradio.com>
Link: https://lore.kernel.org/r/1604955006-9363-1-git-send-email-samuel.nobs@taitradio.com
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-12 09:32:49 +01:00
Qinglang Miao
0c5fc92622 serial: txx9: add missing platform_driver_unregister() on error in serial_txx9_init
Add the missing platform_driver_unregister() before return
from serial_txx9_init in the error handling case when failed
to register serial_txx9_pci_driver with macro ENABLE_SERIAL_TXX9_PCI
defined.

Fixes: ab4382d274 ("tty: move drivers/serial/ to drivers/tty/serial/")
Signed-off-by: Qinglang Miao <miaoqinglang@huawei.com>
Link: https://lore.kernel.org/r/20201103084942.109076-1-miaoqinglang@huawei.com
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-06 17:24:41 +01:00
Lucas Stach
427627a23c tty: serial: imx: enable earlycon by default if IMX_SERIAL_CONSOLE is enabled
Since 699cc4dfd1 (tty: serial: imx: add imx earlycon driver), the earlycon
part of imx serial is a separate driver and isn't necessarily enabled anymore
when the console is enabled. This causes users to loose the earlycon
functionality when upgrading their kenrel configuration via oldconfig.

Enable earlycon by default when IMX_SERIAL_CONSOLE is enabled.

Fixes: 699cc4dfd1 (tty: serial: imx: add imx earlycon driver)
Reviewed-by: Fabio Estevam <festevam@gmail.com>
Reviewed-by: Fugang Duan <fugang.duan@nxp.com>
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Link: https://lore.kernel.org/r/20201105204026.1818219-1-l.stach@pengutronix.de
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-06 17:23:49 +01:00
Claire Chang
912ab37c79 serial: 8250_mtk: Fix uart_get_baud_rate warning
Mediatek 8250 port supports speed higher than uartclk / 16. If the baud
rates in both the new and the old termios setting are higher than
uartclk / 16, the WARN_ON in uart_get_baud_rate() will be triggered.
Passing NULL as the old termios so uart_get_baud_rate() will use
uartclk / 16 - 1 as the new baud rate which will be replaced by the
original baud rate later by tty_termios_encode_baud_rate() in
mtk8250_set_termios().

Fixes: 551e553f0d ("serial: 8250_mtk: Fix high-speed baud rates clamping")
Signed-off-by: Claire Chang <tientzu@chromium.org>
Link: https://lore.kernel.org/r/20201102120749.374458-1-tientzu@chromium.org
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-06 17:23:03 +01:00
Vladimir Oltean
c97f2a6fb3 tty: serial: fsl_lpuart: LS1021A has a FIFO size of 16 words, like LS1028A
Prior to the commit that this one fixes, the FIFO size was derived from
the read-only register LPUARTx_FIFO[TXFIFOSIZE] using the following
formula:

TX FIFO size = 2 ^ (LPUARTx_FIFO[TXFIFOSIZE] - 1)

The documentation for LS1021A is a mess. Under chapter 26.1.3 LS1021A
LPUART module special consideration, it mentions TXFIFO_SZ and RXFIFO_SZ
being equal to 4, and in the register description for LPUARTx_FIFO, it
shows the out-of-reset value of TXFIFOSIZE and RXFIFOSIZE fields as "011",
even though these registers read as "101" in reality.

And when LPUART on LS1021A was working, the "101" value did correspond
to "16 datawords", by applying the formula above, even though the
documentation is wrong again (!!!!) and says that "101" means 64 datawords
(hint: it doesn't).

So the "new" formula created by commit f77ebb241c has all the premises
of being wrong for LS1021A, because it relied only on false data and no
actual experimentation.

Interestingly, in commit c2f448cff2 ("tty: serial: fsl_lpuart: add
LS1028A support"), Michael Walle applied a workaround to this by manually
setting the FIFO widths for LS1028A. It looks like the same values are
used by LS1021A as well, in fact.

When the driver thinks that it has a deeper FIFO than it really has,
getty (user space) output gets truncated.

Many thanks to Michael for pointing out where to look.

Fixes: f77ebb241c ("tty: serial: fsl_lpuart: correct the FIFO depth size")
Suggested-by: Michael Walle <michael@walle.cc>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20201023013429.3551026-1-vladimir.oltean@nxp.com
Reviewed-by:Fugang Duan <fugang.duan@nxp.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-28 13:40:25 +01:00
Russell King
82776f6c75 tty: serial: 21285: fix lockup on open
Commit 293f899594 ("tty: serial: 21285: stop using the unused[]
variable from struct uart_port") introduced a bug which stops the
transmit interrupt being disabled when there are no characters to
transmit - disabling the transmit interrupt at the interrupt controller
is the only way to stop an interrupt storm. If this interrupt is not
disabled when there are no transmit characters, we end up with an
interrupt storm which prevents the machine making forward progress.

Fixes: 293f899594 ("tty: serial: 21285: stop using the unused[] variable from struct uart_port")
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/E1kU4GS-0006lE-OO@rmk-PC.armlinux.org.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-28 13:39:14 +01:00
Linus Torvalds
e731f3146f ARM: SoC platform updates
SoC changes, a substantial part of this is cleanup of some of the older
 platforms that used to have a bunch of board files. In particular:
 
  - Removal of non-DT i.MX platforms that haven't seen activity in years,
    it's time to remove them.
  - A bunch of cleanup and removal of platform data for TI/OMAP platforms,
    moving over to genpd for power/reset control (yay!)
  - Major cleanup of Samsung S3C24xx and S3C64xx platforms, moving them
    closer to multiplatform support (not quite there yet, but getting
    close).
 
 THere are a few other changes too, smaller fixlets, etc. For new
 platform support, the primary ones re:
 
  - New SoC: Hisilicon SD5203, ARM926EJ-S platform.
  - Cpufreq support for i.MX7ULP
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Merge tag 'armsoc-soc' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc

Pull ARM SoC platform updates from Olof Johansson:
 "SoC changes, a substantial part of this is cleanup of some of the
  older platforms that used to have a bunch of board files.

  In particular:

   - Remove non-DT i.MX platforms that haven't seen activity in years,
     it's time to remove them.

   - A bunch of cleanup and removal of platform data for TI/OMAP
     platforms, moving over to genpd for power/reset control (yay!)

   - Major cleanup of Samsung S3C24xx and S3C64xx platforms, moving them
     closer to multiplatform support (not quite there yet, but getting
     close).

  There are a few other changes too, smaller fixlets, etc. For new
  platform support, the primary ones are:

   - New SoC: Hisilicon SD5203, ARM926EJ-S platform.

   - Cpufreq support for i.MX7ULP"

* tag 'armsoc-soc' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (121 commits)
  ARM: mstar: Select MStar intc
  ARM: stm32: Replace HTTP links with HTTPS ones
  ARM: debug: add UART early console support for SD5203
  ARM: hisi: add support for SD5203 SoC
  ARM: omap3: enable off mode automatically
  clk: imx: imx35: Remove mx35_clocks_init()
  clk: imx: imx31: Remove mx31_clocks_init()
  clk: imx: imx27: Remove mx27_clocks_init()
  ARM: imx: Remove unused definitions
  ARM: imx35: Retrieve the IIM base address from devicetree
  ARM: imx3: Retrieve the AVIC base address from devicetree
  ARM: imx3: Retrieve the CCM base address from devicetree
  ARM: imx31: Retrieve the IIM base address from devicetree
  ARM: imx27: Retrieve the CCM base address from devicetree
  ARM: imx27: Retrieve the SYSCTRL base address from devicetree
  ARM: s3c64xx: bring back notes from removed debug-macro.S
  ARM: s3c24xx: fix Wunused-variable warning on !MMU
  ARM: samsung: fix PM debug build with DEBUG_LL but !MMU
  MAINTAINERS: mark linux-samsung-soc list non-moderated
  ARM: imx: Remove remnant board file support pieces
  ...
2020-10-24 10:33:08 -07:00