In the previous patch, we introduced tty_get_char_size() and
tty_get_frame_size() for computing character and frame sizes,
respectively. Here, we make use of them in various tty drivers where
applicable.

The stats look nice: 12 insertions, 169 deletions.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: David Lin <dtwlin@gmail.com>
Cc: Johan Hovold <johan@kernel.org>
Cc: Alex Elder <elder@kernel.org>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Andy Gross <agross@kernel.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Alexandre Torgue <alexandre.torgue@foss.st.com>
Cc: Oliver Neukum <oneukum@suse.com>
Acked-by: NAlex Elder <elder@kernel.org>
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210610090247.2593-4-jslaby@suse.czSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

It's a bit illogical to take magic constants in AUART_LINECTRL_WLEN.
Like in auart_console_get_options(), 2 means 7 bits. Switch
AUART_LINECTRL_WLEN to accept bit length, i.e. let it subtract 5 from
the parameter before doing the logic.

This will ease conversion from CSIZE to bits in mxs_auart_settermios()
in the next patch.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210610090247.2593-2-jslaby@suse.czSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Many tty drivers contain code to compute bits count depending on termios
cflags. So extract this code from serial core to two separate tty helper
functions:
* tty_get_char_size -- only size of a character, without flags,
* tty_get_frame_size -- complete size of a frame including flags.

In the next patch, calls to these new functions replace many copies of
this code.

Note that we accept only cflag as a parameter. That's because some
callers like pch_uart_startup or sunsab_console_setup don't have at hand
termios which we could pass around.

Cc: Joe Perches <joe@perches.com>
Cc: Johan Hovold <johan@kernel.org>
Reviewed-by: NAndy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210610090247.2593-1-jslaby@suse.czSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Defer device probe operation when a DMA channel request probe deferral.

With this change both DMA channels are acquired before DMA channels are
configured. Once no probe deferral is expected, DMAs are
configured and any failure in their configuration will make the driver
to fallback to interrupt mode as prior this change.
Signed-off-by: NErwan Le Ray <erwan.leray@foss.st.com>
Signed-off-by: NEtienne Carriere <etienne.carriere@foss.st.com>
Link: https://lore.kernel.org/r/20210610100020.2318-1-erwan.leray@foss.st.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Request the RX mailbox only after initializing the UART data
structures. Otherwise it can rarely happen that the receive
callback is called before the UART is ready.

Fixes: 2d908b38 ("serial: Add Tegra Combined UART driver")
Signed-off-by: NMikko Perttunen <mperttunen@nvidia.com>
Link: https://lore.kernel.org/r/20210609155655.3567545-1-mperttunen@nvidia.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Stop dmaengine transfer in sci_stop_tx(). Otherwise, the following
message is possible output when system enters suspend and while
transferring data, because clearing TIE bit in SCSCR is not able to
stop any dmaengine transfer.

    sh-sci e6550000.serial: ttySC1: Unable to drain transmitter

Note that this driver has already used some #ifdef in the .c file
so that this patch also uses #ifdef to fix the issue. Otherwise,
build errors happens if the CONFIG_SERIAL_SH_SCI_DMA is disabled.

Fixes: 73a19e4c ("serial: sh-sci: Add DMA support.")
Cc: <stable@vger.kernel.org> # v4.9+
Signed-off-by: NYoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Link: https://lore.kernel.org/r/20210610110806.277932-1-yoshihiro.shimoda.uh@renesas.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

We would like to use DMI matching in other functions as well.
Hence, extract it as exar_get_platform() helper function.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20210608144239.12697-2-andriy.shevchenko@linux.intel.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

It's possible that during ->exit() the private_data is NULL,
for instance when there was no GPIO device instantiated.
Due to this we may not dereference it. Add a respective check.

Note, for now ->exit() only makes sense when GPIO device
was instantiated, that's why we may use the check for entire
function.

Fixes: 81171e7d ("serial: 8250_exar: Constify the software nodes")
Reported-by: NMaxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: NMaxim Levitsky <mlevitsk@redhat.com>
Link: https://lore.kernel.org/r/20210608144239.12697-1-andriy.shevchenko@linux.intel.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The last user of the STEPFN() macro was removed in commit
d5cb1319 ("serial: sh-sci: Remove manual break debouncing").
Reviewed-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: NNiklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/970387d104dea5bb7ea674bb89229641467e629b.1623076891.git.geert+renesas@glider.beSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add serial support for RZ/G2L SoC with earlycon and
extended mode register support.
Signed-off-by: NBiju Das <biju.das.jz@bp.renesas.com>
Signed-off-by: NLad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Link: https://lore.kernel.org/r/20210603221758.10305-11-prabhakar.mahadev-lad.rj@bp.renesas.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Remove the hack to assign the global console_port variable at probe time.
This assumption that cons->index is -1 is wrong for systems that specify
'console=' in the cmdline (or 'stdout-path' in dts). Hence, on such system
the actual console assignment is ignored, and the first UART that happens
to be probed is used as console instead.

Move the logic to console_setup() and map the console to the correct port
through the array of available ports instead.
Signed-off-by: NDaniel Mack <daniel@zonque.org>
Link: https://lore.kernel.org/r/20210528133321.1859346-1-daniel@zonque.orgSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

In order to optimize serial communication (performance/throughput VS
latency), we may need to tweak DMA period number and size. This adds
DT properties to configure those values before initialising DMA.
The defaults will stay the same as before.

[update documentation and commit message, rebase to current master,
switch back to DT instead of sysfs]
Signed-off-by: NFabien Lahoudere <fabien.lahoudere@collabora.com>
Signed-off-by: NSebastian Reichel <sebastian.reichel@collabora.com>
Link: https://lore.kernel.org/r/20210430175038.103226-2-sebastian.reichel@collabora.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This reverts commit 31fae7c8.

Tony writes:
	I just noticed this causes the following regression in Linux
	next when pressing a key on uart console after boot at least on
	omap3. This seems to happen on serial_port_in(port, UART_RX) in
	the quirk handling.

So let's drop this.

Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/YLCCJzkkB4N7LTQS@atomide.com
Fixes: 31fae7c8 ("serial: 8250: 8250_omap: Fix possible interrupt storm")
Reported-by: NTony Lindgren <tony@atomide.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Vignesh Raghavendra <vigneshr@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

In commit 8428413b ("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: 8428413b ("serial: 8250_pci: Implement MSI(-X) support")
Cc: <stable@vger.kernel.org>
Signed-off-by: NChristian Gmeiner <christian.gmeiner@gmail.com>
Link: https://lore.kernel.org/r/20210527095529.26281-1-christian.gmeiner@gmail.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

In the probe function, if the final 'serial_config()' fails, 'info' is
leaking.

Add a resource handling path to free this memory.
Signed-off-by: NChristophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/dc25f96b7faebf42e60fe8d02963c941cf4d8124.1621971720.git.christophe.jaillet@wanadoo.frSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

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: NZheyu Ma <zheyuma97@gmail.com>
Signed-off-by: NZheyu 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: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This reverts commit 064b6e47 as it
wasn't quite ready yet :(

Cc: Biju Das <biju.das.jz@bp.renesas.com>
CC: Geert Uytterhoeven <geert+renesas@glider.be>
Reported-by: NLad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add support for new HPE serial device.  It is MSI enabled,
but otherwise similar to legacy HP server serial devices.
Tested-by: NJerry Hoemann <jerry.hoemann@hpe.com>
Signed-off-by: NRandy Wright <rwright@hpe.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/1621009614-28836-1-git-send-email-rwright@hpe.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

It is possible that RX TIMEOUT is signalled after RX FIFO has been
drained, in which case a dummy read of RX FIFO is required to clear RX
TIMEOUT condition. Otherwise, RX TIMEOUT condition is not cleared
leading to an interrupt storm

Cc: stable@vger.kernel.org
Reported-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NVignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/20210511151955.28071-1-vigneshr@ti.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

BIT(x) improves readability and safety with respect to shifts.
Reviewed-by: NJiri Slaby <jirislaby@kernel.org>
Signed-off-by: NAndrew Jeffery <andrew@aj.id.au>
Link: https://lore.kernel.org/r/20210520021334.497341-3-andrew@aj.id.auSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

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: NChiaWei Wang <chiawei_wang@aspeedtech.com>
Reviewed-by: NJiri Slaby <jirislaby@kernel.org>
Signed-off-by: NAndrew Jeffery <andrew@aj.id.au>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20210520021334.497341-2-andrew@aj.id.auSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

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

 drivers/tty/serial/xilinx_uartps.c:496: warning: expecting prototype for cdns_uart_clk_notitifer_cb(). Prototype was for cdns_uart_clk_notifier_cb() instead

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: linux-serial@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Reviewed-by: NMichal Simek <michal.simek@xilinx.com>
Signed-off-by: NLee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20210520121906.3468725-12-lee.jones@linaro.orgSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

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

 drivers/tty/serial/st-asc.c:73: warning: expecting prototype for Some of status comes from higher bits of the character and some come from(). Prototype was for ASC_RXBUF_DUMMY_RX() instead

Cc: Patrice Chotard <patrice.chotard@foss.st.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-serial@vger.kernel.org
Signed-off-by: NLee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20210520121906.3468725-10-lee.jones@linaro.orgSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

After the previous patch, we can make port passed to
serial8250_find_match_or_unused const. And then we can make const also
port of serial8250_register_8250_port.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210519072153.3859-2-jslaby@suse.czSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

* make parameters const (as they are only read)
* return bool (as comparison results are returned)
* add \n before final return
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210519072153.3859-1-jslaby@suse.czSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Most litex boards using RISC-V soft cores us the sbi earlycon, however
this is not available for non RISC-V litex SoC's.  This patch enables
earlycon for liteuart which is available on all Litex SoC's making
support for earycon debugging more widely available.

Cc: Florent Kermarrec <florent@enjoy-digital.fr>
Cc: Mateusz Holenko <mholenko@antmicro.com>
Cc: Joel Stanley <joel@jms.id.au>
Cc: Gabriel L. Somlo <gsomlo@gmail.com>
Reviewed-and-tested-by: NGabriel Somlo <gsomlo@gmail.com>
Reviewed-by: NJiri Slaby <jirislaby@kernel.org>
Reviewed-by: NJoel Stanley <joel@jms.id.au>
Signed-off-by: NStafford Horne <shorne@gmail.com>
Link: https://lore.kernel.org/r/20210517115453.24365-1-shorne@gmail.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Replace open coded variants of devm_clk_get_optional().
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20210517173415.7483-1-andriy.shevchenko@linux.intel.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

In some configurations, mainly ACPI-based, the clock frequency of the device
is supplied by very well established 'clock-frequency' property. Hence, try
to get it from the property at last if no other providers are available.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20210517172930.83353-1-andriy.shevchenko@linux.intel.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

There's no need to initialise irq-flags variables before saving the
interrupt state.

Drop the redundant initialisations from drivers that got this wrong.
Acked-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NJohan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20210519092541.10137-1-johan@kernel.orgSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The variable c is being initialized with a value that is never
read, it is being updated later on. The assignment is redundant and
can be removed.
Reviewed-by: NJiri Slaby <jirislaby@kernel.org>
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Addresses-Coverity: ("Unused value")
Link: https://lore.kernel.org/r/20210513230224.138859-1-colin.king@canonical.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add serial support for RZ/G2L SoC with earlycon and
extended mode register support.
Signed-off-by: NBiju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: NLad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Link: https://lore.kernel.org/r/20210514192218.13022-11-prabhakar.mahadev-lad.rj@bp.renesas.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Now the DT bindings has a property to get the FIFO size for a particular port,
retrieve it and use to setup the FIFO interrupts threshold.
Reviewed-by: NKevin Hilman <khilman@baylibre.com>
Signed-off-by: NNeil Armstrong <narmstrong@baylibre.com>
Link: https://lore.kernel.org/r/20210518075833.3736038-3-narmstrong@baylibre.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Include the more general linux/io.h instead of asm/io.h
as checkpatch suggests.
Signed-off-by: NZihao Tang <tangzihao1@hisilicon.com>
Signed-off-by: NJay Fang <f.fangjian@huawei.com>
Link: https://lore.kernel.org/r/1620874904-39285-13-git-send-email-f.fangjian@huawei.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Include the more general linux/io.h instead of asm/io.h
as checkpatch suggests.
Signed-off-by: NZihao Tang <tangzihao1@hisilicon.com>
Signed-off-by: NJay Fang <f.fangjian@huawei.com>
Link: https://lore.kernel.org/r/1620874904-39285-12-git-send-email-f.fangjian@huawei.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Include the more general linux/io.h instead of asm/io.h
as checkpatch suggests.
Signed-off-by: NZihao Tang <tangzihao1@hisilicon.com>
Signed-off-by: NJay Fang <f.fangjian@huawei.com>
Link: https://lore.kernel.org/r/1620874904-39285-11-git-send-email-f.fangjian@huawei.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Include the more general linux/io.h instead of asm/io.h
as checkpatch suggests.
Signed-off-by: NZihao Tang <tangzihao1@hisilicon.com>
Signed-off-by: NJay Fang <f.fangjian@huawei.com>
Link: https://lore.kernel.org/r/1620874904-39285-10-git-send-email-f.fangjian@huawei.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Include the more general linux/io.h instead of asm/io.h
as checkpatch suggests.
Signed-off-by: NZihao Tang <tangzihao1@hisilicon.com>
Signed-off-by: NJay Fang <f.fangjian@huawei.com>
Link: https://lore.kernel.org/r/1620874904-39285-9-git-send-email-f.fangjian@huawei.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Include the more general linux/io.h instead of asm/io.h
as checkpatch suggests.
Signed-off-by: NZihao Tang <tangzihao1@hisilicon.com>
Signed-off-by: NJay Fang <f.fangjian@huawei.com>
Link: https://lore.kernel.org/r/1620874904-39285-8-git-send-email-f.fangjian@huawei.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Include the more general linux/io.h instead of asm/io.h
as checkpatch suggests.
Signed-off-by: NZihao Tang <tangzihao1@hisilicon.com>
Signed-off-by: NJay Fang <f.fangjian@huawei.com>
Link: https://lore.kernel.org/r/1620874904-39285-7-git-send-email-f.fangjian@huawei.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Include the more general linux/io.h instead of asm/io.h
as checkpatch suggests.
Signed-off-by: NZihao Tang <tangzihao1@hisilicon.com>
Signed-off-by: NJay Fang <f.fangjian@huawei.com>
Link: https://lore.kernel.org/r/1620874904-39285-6-git-send-email-f.fangjian@huawei.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>