This attempts to fix a bug found with a serial port card which uses
an MCS9922 chip, one of the 4 models for which MSI-X interrupts are
currently supported. I don't possess such a card, and i'm not
experienced with the serial subsystem, so this patch is based on what
i think i found as a likely reason for failure, based on walking the
user who actually owns the card through some diagnostic.
The user who reported the problem finds the following in his dmesg
output for the relevant ttyS4 and ttyS5:
[ 0.580425] serial 0000:02:00.0: enabling device (0000 -> 0003)
[ 0.601448] 0000:02:00.0: ttyS4 at I/O 0x3010 (irq = 125, base_baud = 115200) is a ST16650V2
[ 0.603089] serial 0000:02:00.1: enabling device (0000 -> 0003)
[ 0.624119] 0000:02:00.1: ttyS5 at I/O 0x3000 (irq = 126, base_baud = 115200) is a ST16650V2
...
[ 6.323784] genirq: Flags mismatch irq 128. 00000080 (ttyS5) vs. 00000000 (xhci_hcd)
[ 6.324128] genirq: Flags mismatch irq 128. 00000080 (ttyS5) vs. 00000000 (xhci_hcd)
...
Output of setserial -a:
/dev/ttyS4, Line 4, UART: 16650V2, Port: 0x3010, IRQ: 127
Baud_base: 115200, close_delay: 50, divisor: 0
closing_wait: 3000
Flags: spd_normal skip_test
This suggests to me that the serial driver wants to register and share a
MSI/MSI-X irq 128 with the xhci_hcd driver, whereas the xhci driver does
not want to share the irq, as flags 0x00000080 (== IRQF_SHARED) from the
serial port driver means to share the irq, and this mismatch ends in some
failed irq init?
With this setup, data reception works very unreliable, with dropped data,
already at a transmission rate of only a 16 Bytes chunk every 1/120th of
a second, ie. 1920 Bytes/sec, presumably due to rx fifo overflow due to
mishandled or not used at all rx irq's?
See full discussion thread with attempted diagnosis at:
https://psychtoolbox.discourse.group/t/issues-with-iscan-serial-port-recording/3886
Disabling the use of MSI interrupts for the serial port pci card did
fix the reliability problems. The user executed the following sequence
of commands to achieve this:
echo 0000:02:00.0 | sudo tee /sys/bus/pci/drivers/serial/unbind
echo 0000:02:00.1 | sudo tee /sys/bus/pci/drivers/serial/unbind
echo 0 | sudo tee /sys/bus/pci/devices/0000:02:00.0/msi_bus
echo 0 | sudo tee /sys/bus/pci/devices/0000:02:00.1/msi_bus
echo 0000:02:00.0 | sudo tee /sys/bus/pci/drivers/serial/bind
echo 0000:02:00.1 | sudo tee /sys/bus/pci/drivers/serial/bind
This resulted in the following log output:
[ 82.179021] pci 0000:02:00.0: MSI/MSI-X disallowed for future drivers
[ 87.003031] pci 0000:02:00.1: MSI/MSI-X disallowed for future drivers
[ 98.537010] 0000:02:00.0: ttyS4 at I/O 0x3010 (irq = 17, base_baud = 115200) is a ST16650V2
[ 103.648124] 0000:02:00.1: ttyS5 at I/O 0x3000 (irq = 18, base_baud = 115200) is a ST16650V2
This patch attempts to fix the problem by disabling irq sharing when
using MSI irq's. Note that all i know for sure is that disabling MSI
irq's fixed the problem for the user, so this patch could be wrong and
is untested. Please review with caution, keeping this in mind.
Fixes: 8428413b1d ("serial: 8250_pci: Implement MSI(-X) support")
Cc: Ralf Ramsauer <ralf.ramsauer@oth-regensburg.de>
Cc: stable <stable@vger.kernel.org>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>
Link: https://lore.kernel.org/r/20210729043306.18528-1-mario.kleiner.de@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix uart corruption issue when rx power off.
Add spin lock in mtk8250_dma_rx_complete function in APDMA mode.
when uart is used as a communication port with external device(GPS).
when external device(GPS) power off, the power of rx pin is also from
1.8v to 0v. Even if there is not any data in rx. But uart rx pin can
capture the data "0".
If uart don't receive any data in specified cycle, uart will generates
BI(Break interrupt) interrupt.
If external device(GPS) power off, we found that BI interrupt appeared
continuously and very frequently.
When uart interrupt type is BI, uart IRQ handler(8250 framwork
API:serial8250_handle_irq) will push data to tty buffer.
mtk8250_dma_rx_complete is a task of mtk_uart_apdma_rx_handler.
mtk8250_dma_rx_complete priority is lower than uart irq
handler(serial8250_handle_irq).
if we are in process of mtk8250_dma_rx_complete, uart appear BI
interrupt:1)serial8250_handle_irq will priority execution.2)it may cause
write tty buffer conflict in mtk8250_dma_rx_complete.
So the spin lock protect the rx receive data process is not break.
Signed-off-by: Zhiyong Tao <zhiyong.tao@mediatek.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20210729084640.17613-2-zhiyong.tao@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Elkhart Lake UARTs are PCI enumerated Synopsys DesignWare v4.0+ UART
integrated with Intel iDMA 32-bit DMA controller. There is a specific
driver to handle them, i.e. 8250_lpss. Hence, disable 8250_pci
enumeration for these UARTs.
Fixes: 1b91d97c66 ("serial: 8250_lpss: Add ->setup() for Elkhart Lake ports")
Fixes: 4f912b898d ("serial: 8250_lpss: Enable HS UART on Elkhart Lake")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20210713101739.36962-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The 8250 handle_irq callback is not just called from the interrupt
handler but also from a timer callback when polling (e.g. for ports
without an interrupt line). Consequently the callback must explicitly
disable interrupts to avoid a potential deadlock with another interrupt
in polled mode.
Add back an irqrestore-version of the sysrq port-unlock helper and use
it in the 8250 callbacks that need it.
Fixes: 75f4e830fa ("serial: do not restore interrupt state in sysrq helper")
Cc: stable@vger.kernel.org # 5.13
Cc: Joel Stanley <joel@jms.id.au>
Cc: Andrew Jeffery <andrew@aj.id.au>
Reported-by: kernel test robot <oliver.sang@intel.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20210714080427.28164-1-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Make sure only actual 8 bits of the IIR register are used in determining
the port type in `autoconfig'.
The `serial_in' port accessor returns the `unsigned int' type, meaning
that with UPIO_AU, UPIO_MEM16, UPIO_MEM32, and UPIO_MEM32BE access types
more than 8 bits of data are returned, of which the high order bits will
often come from bus lines that are left floating in the data phase. For
example with the MIPS Malta board's CBUS UART, where the registers are
aligned on 8-byte boundaries and which uses 32-bit accesses, data as
follows is returned:
YAMON> dump -32 0xbf000900 0x40
BF000900: 1F000942 1F000942 1F000900 1F000900 ...B...B........
BF000910: 1F000901 1F000901 1F000900 1F000900 ................
BF000920: 1F000900 1F000900 1F000960 1F000960 ...........`...`
BF000930: 1F000900 1F000900 1F0009FF 1F0009FF ................
YAMON>
Evidently high-order 24 bits return values previously driven in the
address phase (the 3 highest order address bits used with the command
above are masked out in the simple virtual address mapping used here and
come out at zeros on the external bus), a common scenario with bus lines
left floating, due to bus capacitance.
Consequently when the value of IIR, mapped at 0x1f000910, is retrieved
in `autoconfig', it comes out at 0x1f0009c1 and when it is right-shifted
by 6 and then assigned to 8-bit `scratch' variable, the value calculated
is 0x27, not one of 0, 1, 2, 3 expected in port type determination.
Fix the issue then, by assigning the value returned from `serial_in' to
`scratch' first, which masks out 24 high-order bits retrieved, and only
then right-shift the resulting 8-bit data quantity, producing the value
of 3 in this case, as expected. Fix the same issue in `serial_dl_read'.
The problem first appeared with Linux 2.6.9-rc3 which predates our repo
history, but the origin could be identified with the old MIPS/Linux repo
also at: <git://git.kernel.org/pub/scm/linux/kernel/git/ralf/linux.git>
as commit e0d2356c0777 ("Merge with Linux 2.6.9-rc3."), where code in
`serial_in' was updated with this case:
+ case UPIO_MEM32:
+ return readl(up->port.membase + offset);
+
which made it produce results outside the unsigned 8-bit range for the
first time, though obviously it is system dependent what actual values
appear in the high order bits retrieved and it may well have been zeros
in the relevant positions with the system the change originally was
intended for. It is at that point that code in `autoconf' should have
been updated accordingly, but clearly it was overlooked.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Cc: stable@vger.kernel.org # v2.6.12+
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2106260516220.37803@angie.orcam.me.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On K3 family of SoCs (which includes AM654 SoC), it is observed 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, this would lead to an interrupt storm.
Fix this by introducing UART_RX_TIMEOUT_QUIRK flag and doing a dummy
read in IRQ handler when RX TIMEOUT is reported with no data in RX FIFO.
Fixes: be70874498 ("serial: 8250_omap: Add support for AM654 UART controller")
Reported-by: Jan Kiszka <jan.kiszka@siemens.com>
Tested-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/20210622145704.11168-1-vigneshr@ti.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The GLOBETROTTER.cis entry in serial_cs matches more devices than
intended and breaks them. Remove it.
Example: # pccardctl info
PRODID_1="Option International
"
PRODID_2="GSM-Ready 56K/ISDN
"
PRODID_3="021
"
PRODID_4="A
"
MANFID=0013,0000
FUNCID=0
result:
pcmcia 0.0: Direct firmware load for cis/GLOBETROTTER.cis failed with error -2
The GLOBETROTTER.cis is nowhere to be found. There's GLOBETROTTER.cis.ihex at
https://netdev.vger.kernel.narkive.com/h4inqdxM/patch-axnet-cs-fix-phy-id-detection-for-bogus-asix-chip#post41
It's from completely diffetent card:
vers_1 4.1, "Option International", "GSM/GPRS GlobeTrotter", "001", "A"
Signed-off-by: Ondrej Zary <linux@zary.sk>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20210611201940.23898-1-linux@zary.sk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Handle custom baud rates requested in the UPF_MAGIC_MULTIPLIER range
with BOTHER. Currently matching is exact, that is if a baud rate that
is not either of clk/4 or clk/8 is requested, then we fall through to
the default case, which will just divide the clock rate by 16 times the
rate requested, round it to closest integer, and possibly yield even
worse results then if clamping to the extra baud rates was chosen.
So for example if we have the usual base rate of 115200 and request a
rate of 230399, then the fall-through divisor calculation will yield 1,
and consequently the baud rate of 115200 will be programmed even though
obviously the magic rate of 230400 would be more appropriate.
Make the selection of the magic rates range-qualified then and use clk/4
for rates from clk/6 up (assuming `serial8250_get_baud_rate' has already
rejected any rates too far beyond clk/4), and otherwise use clk/8 for
rates from clk/12 up, and finally fall through to the standard divisor
calculation. Explicitly void using the undocumented rate of 153600bps
and stick to documented divisor values only.
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2105200232090.29169@angie.orcam.me.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Support for magic baud rate divisors of 32770 and 32769 used with SMSC
Super I/O chips for extra baud rates of 230400 and 460800 respectively
where base rate is 115200[1] has been added around Linux 2.5.64, which
predates our repo history, but the origin could be identified as commit
2a717aad772f ("Merge with Linux 2.5.64.") with the old MIPS/Linux repo
also at: <git://git.kernel.org/pub/scm/linux/kernel/git/ralf/linux.git>.
Code that is now in `serial8250_do_get_divisor' was added back then to
`serial8250_get_divisor', but that code would only ever trigger if one
of the higher baud rates was actually requested, and that cannot ever
happen, because the earlier call to `serial8250_get_baud_rate' never
returns them. This is because it calls `uart_get_baud_rate' with the
maximum requested being the base rate, that is clk/16 or 115200 for SMSC
chips at their nominal clock rate.
Fix it then and allow UPF_MAGIC_MULTIPLIER baud rates to be selected, by
requesting the maximum baud rate of clk/4 rather than clk/16 if the flag
has been set. Also correct the minimum baud rate, observing that these
ports only support actual (non-magic) divisors of up to 32767 only.
References:
[1] "FDC37M81x, PC98/99 Compliant Enhanced Super I/O Controller with
Keyboard/Mouse Wake-Up", Standard Microsystems Corporation, Rev.
03/27/2000, Table 31 - "Baud Rates", p. 77
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2105190412280.29169@angie.orcam.me.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Contrary to what SMSC documentation says and unlike NS16C550A UARTs the
SMSC Super I/O IC claims compatibility with the SMSC UART implementation
does not support dividing the internal PLL clock by any divisor from 1
to 65535[1], with the exception of two magic divisors of 32769 and 32770
used respectively to select the high-speed data rates of 460800bps and
230400bps[2] if enabled on a port-by-port basis in with the Serial Port
Mode Register in the Device Configuration Space[3][4].
Instead empirical evidence indicates that the divisor, as stored in the
DLL and DLM register pair, has the range of 1 to 32767 only, and bit 7
of the DLM register (bit 15 of the divisor) effectively serves as a
selection bit for the prescaler from the base frequency of 7.3728MHz,
either 4 if the bit is 0, or 1 if the bit is 1 and high-speed operation
has been enabled with the Serial Port Mode Register.
So if high-speed operation has not been enabled, then say the values of
1 and 32769 (0x8001) written into the combined DLL and DLM register pair
both select the divisor of 1 and the baud rate of 115200bps.
[1] "FDC37M81x, PC98/99 Compliant Enhanced Super I/O Controller with
Keyboard/Mouse Wake-Up", Standard Microsystems Corporation, Rev.
03/27/2000, Section "Programmable Baud Rate Generator (and Divisor
Latches DLH, DLL)", p. 75
[2] same, Table 31 - "Baud Rates", p. 77
[3] same, Table 60 - "Serial Port 1, Logical Device 4 [Logical Device
Number = 0x04]", p. 153
[4] same, Table 61 - "Serial Port 2, Logical Device 5 [Logical Device
Number = 0x05]", p. 153
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2106092330530.5469@angie.orcam.me.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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: 7106b4e333 ("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>
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>
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Merge tag 'v5.13-rc6' into tty-next
We want the tty fixes in here as well.
Signed-off-by: Greg 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: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20210608144239.12697-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg 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: 81171e7d31 ("serial: 8250_exar: Constify the software nodes")
Reported-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Maxim Levitsky <mlevitsk@redhat.com>
Link: https://lore.kernel.org/r/20210608144239.12697-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit 31fae7c8b1.
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: 31fae7c8b1 ("serial: 8250: 8250_omap: Fix possible interrupt storm")
Reported-by: Tony Lindgren <tony@atomide.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Vignesh Raghavendra <vigneshr@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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>
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>
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: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/20210511151955.28071-1-vigneshr@ti.com
Signed-off-by: Greg 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: 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>
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: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210519072153.3859-2-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tty_buffer_space_avail returns values >= 0, so make it clear by the
return type.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Joel Stanley <joel@jms.id.au>
Link: https://lore.kernel.org/r/20210505091928.22010-25-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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>
This loop ends on -1 so the error message will never be printed.
Fixes: 4bcf59a5de ("serial: 8250: 8250_omap: Account for data in flight during DMA teardown")
Reviewed-by: Alexander Sverdlin <alexander.sverdlin@gmail.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/YIpd+kOpXKMpEXPf@mwanda
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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>
Use 'hlist_for_each_entry' instead of hand writing it.
This saves a few lines of code.
The comment about warning generated by some gcc version is also removed.
The way 'hlist_for_each_entry' is written should prevent such a warning to
be emitted.
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/14024ddeb2b3a8c5b0138b5ba5083f54d00164a9.1619594713.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Our SoC's have always had a NS16650A UART core and older SoC's would
have a compatible string of: 'compatible = ""ns16550a"' and use the
8250_of driver. Our newer SoC's have added enhancements to the base
core to add support for DMA and accurate high speed baud rates and use
this newer 8250_bcm7271 driver. The Device Tree node for our enhanced
UARTs has a compatible string of: 'compatible = "brcm,bcm7271-uart",
"ns16550a"''. With both drivers running and the link order setup so
that the 8250_bcm7217 driver is initialized before the 8250_of driver,
we should bind the 8250_bcm7271 driver to the enhanced UART, or for
upstream kernels that don't have the 8250_bcm7271 driver, we bind to
the 8250_of driver.
The problem is that when both the 8250_of and 8250_bcm7271 drivers
were running, occasionally the 8250_of driver would be bound to the
enhanced UART instead of the 8250_bcm7271 driver. This was happening
because we use SCMI based clocks which come up late in initialization
and cause probe DEFER's when the two drivers get their clocks.
Occasionally the SCMI clock would become ready between the 8250_bcm7271
probe and the 8250_of probe and the 8250_of driver would be bound. To
fix this we decided to config only our 8250_bcm7271 driver and added
"ns16665a0" to the compatible string so the driver would work on our
older system.
This commit has of_platform_serial_probe() check specifically for the
"brcm,bcm7271-uart" and whether its companion driver is enabled. If it
is the case, and the clock provider is not ready, we want to make sure
that when the 8250_bcm7271.c driver returns EPROBE_DEFER, we are not
getting the UART registered via 8250_of.c.
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Jim Quinlan <jim2101024@gmail.com>
Signed-off-by: Al Cooper <alcooperx@gmail.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20210423183206.3917725-1-f.fainelli@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Previously this driver's use of devm_ioremap_resource() led to
duplicated calls to __release_region() when unbinding it (one from
serial8250_release_std_resource() and one from devres_release_all()),
the second of which resulted in a warning message:
# echo 1e787000.serial > /sys/bus/platform/drivers/aspeed-vuart/unbind
[33091.774200] Trying to free nonexistent resource <000000001e787000-000000001e78703f>
With this change the driver uses the generic serial8250 code's
UPF_IOREMAP to take care of the register mapping automatically instead
of doing its own devm_ioremap_resource(), thus avoiding the duplicate
__release_region() on unbind.
In doing this we eliminate vuart->regs, since it merely duplicates
vuart->port->port.membase, which we now use for our I/O accesses.
Reported-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Zev Weiss <zev@bewilderbeest.net>
Link: https://lore.kernel.org/r/20210510014231.647-4-zev@bewilderbeest.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Previously this had only been initialized if we hit the throttling path
in aspeed_vuart_handle_irq(); moving it to the probe function is a
slight consistency improvement and avoids redundant reinitialization in
the interrupt handler. It also serves as preparation for converting the
driver's I/O accesses to use port->port.membase instead of its own
vuart->regs.
Signed-off-by: Zev Weiss <zev@bewilderbeest.net>
Link: https://lore.kernel.org/r/20210510014231.647-3-zev@bewilderbeest.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This is a small prepatory step for changing the way this driver does
its I/O accesses.
Reviewed-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Zev Weiss <zev@bewilderbeest.net>
Link: https://lore.kernel.org/r/20210510014231.647-2-zev@bewilderbeest.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Allow more drivers to be compile tested more easily, for example, when
doing subsystem-wide changes.
Verified on X86_64 as well as arm, powerpc and m68k with minimal configs
in order to catch missing implicit build dependencies (e.g. MAILBOX for
SERIAL_TEGRA_TCU).
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20210422080211.29326-1-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The uart_unlock_and_check_sysrq() helper can be used to defer processing
of sysrq until the interrupt handler has released the port lock and is
about to return.
Since commit 81e2073c17 ("genirq: Disable interrupts for force
threaded handlers") interrupt handlers that are not explicitly requested
as threaded are always called with interrupts disabled and there is no
need to save the interrupt state when taking the port lock.
Instead of adding another sysrq helper for when the interrupt state has
not needlessly been saved, drop the state parameter from
uart_unlock_and_check_sysrq() and update its callers to no longer
explicitly disable interrupts in their interrupt handlers.
Cc: Joel Stanley <joel@jms.id.au>
Cc: Andrew Jeffery <andrew@aj.id.au>
Cc: Andy Gross <agross@kernel.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20210416140557.25177-2-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
These allow describing all the Aspeed VUART attributes currently
available via sysfs. aspeed,lpc-interrupts provides a replacement for
the deprecated aspeed,sirq-polarity-sense property.
Reviewed-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Zev Weiss <zev@bewilderbeest.net>
Link: https://lore.kernel.org/r/20210412034712.16778-4-zev@bewilderbeest.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This splits dedicated aspeed_vuart_set_{sirq,lpc_address}() functions
out of the sysfs store functions in preparation for adding DT
properties that will be poking the same registers. While we're at it,
these functions now provide some basic bounds-checking on their
arguments.
Reviewed-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Zev Weiss <zev@bewilderbeest.net>
Link: https://lore.kernel.org/r/20210412034712.16778-3-zev@bewilderbeest.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
symbol 'brcmuart_debugfs_root' is not used outside of 8250_bcm7271.c,
so this commit marks it static.
Signed-off-by: Zucheng Zheng <zhengzucheng@huawei.com>
Link: https://lore.kernel.org/r/20210401074919.56573-1-zhengzucheng@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In case of error, the function devm_ioremap() returns NULL
pointer not ERR_PTR(). The IS_ERR() test in the return value
check should be replaced with NULL test.
Fixes: 41a469482d ("serial: 8250: Add new 8250-core based Broadcom STB driver")
Reported-by: Hulk Robot <hulkci@huawei.com>
Reviewed-by: Al Cooper <alcooperx@gmail.com>
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Link: https://lore.kernel.org/r/20210329140659.1832950-1-weiyongjun1@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add a compatible string for the UART inside the Nuvoton WPCM450 SoC.
It works the same as the UART in NPCM750.
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Link: https://lore.kernel.org/r/20210320181610.680870-10-j.neuschaefer@gmx.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add a UART driver for the new Broadcom 8250 based STB UART. The new
UART is backward compatible with the standard 8250, but has some
additional features. The new features include a high accuracy baud
rate clock system and DMA support.
The driver will use the new optional BAUD MUX clock to select the best
one of the four master clocks (81MHz, 108MHz, 64MHz and 48MHz) to feed
the baud rate selection logic for any requested baud rate. This allows
for more accurate BAUD rates when high speed baud rates are selected.
The driver will use the new UART DMA hardware if the UART DMA registers
are specified in Device Tree "reg" property.
The driver also sets the UPSTAT_AUTOCTS flag when hardware flow control
is enabled. This flag is needed for UARTs that don't assert a CTS
changed interrupt when CTS changes and AFE (Hardware Flow Control) is
enabled.
The driver also contains a workaround for a bug in the Synopsis 8250
core. The problem is that at high baud rates, the RX partial FIFO
timeout interrupt can occur but there is no RX data (DR not set in
the LSR register). In this case the driver will not read the Receive
Buffer Register, which clears the interrupt, and the system will get
continuous UART interrupts until the next RX character arrives. The
fix originally suggested by Synopsis was to read the Receive Buffer
Register and discard the character when the DR bit in the LSR was
not set, to clear the interrupt. The problem was that occasionally
a character would arrive just after the DR bit check and a valid
character would be discarded. The fix that was added will clear
receive interrupts to stop the interrupt, deassert RTS to insure
that no new data can arrive, wait for 1.5 character times for the
sender to react to RTS and then check for data and either do a dummy
read or a valid read. Debugfs error counters were also added and were
used to help create test software that would cause the error condition.
The counters can be found at:
/sys/kernel/debug/bcm7271-uart/<device-name>/stats
This also includes a few fixes for build warnings reported by
the kernel test robot.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Al Cooper <alcooperx@gmail.com>
Link: https://lore.kernel.org/r/20210325185256.16156-3-alcooperx@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
platform_get_irq() has already checked and printed the return value,
the printing here is nothing special, it is not necessary at all.
Signed-off-by: Wang Qing <wangqing@vivo.com>
Link: https://lore.kernel.org/r/1615621707-2330-1-git-send-email-wangqing@vivo.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Software node is always created for additional device
properties. If the properties are constant, the software
node can also be constant.
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20210304081311.17340-1-heikki.krogerus@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The caller expects from the others (pfc_config and multi_config) to
return standard error values. So do the same for simple_config too.
We invert the if condition to handle the error case.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210302062214.29627-13-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Initialize the variables directly by initializers in definitions. This
is expected/usual for these kind of callback.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210302062214.29627-12-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This really eliminates multiplications from the assembly. I would have
thought they are optimized by inlining ktime_set, but not on x86_64 with
gcc 10.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210302062214.29627-11-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The Cyclades driver was orphaned by commit d459883e6c (MAINTAINERS:
remove two dead e-mail) 13 years ago. Noone stepped up to take care of
them and to fix all the issues the driver has.
On the top of that, there is no way to obtain the firmware for Z cards
from the vendor as cyclades.com ceased to exist.
So it's time to drop the driver with all its traces.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210302062214.29627-5-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since commit d73dfc6a41 ("serial: 8250_pci: remove __devexit
usage") in v3.9, the 8250/16550 PCI serial driver no longer has any code
or data located in initmem, hence there is no need to annotate the
pci_serial_quirks structure with __refdata. Drop the annotation, to
avoid suppressing future section warnings.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20201211133907.2970460-1-geert+renesas@glider.be
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Mario Kleiner
Zhiyong Tao
Andy Shevchenko
Johan Hovold
Maciej W. Rozycki
Vignesh Raghavendra
Ondrej Zary
Greg Kroah-Hartman
Christian Gmeiner
Christophe JAILLET
Randy Wright
Andrew Jeffery
Jiri Slaby
Maximilian Luz
Dan Carpenter
Jim Quinlan
Zev Weiss
Zucheng Zheng
Wei Yongjun
Jonathan Neuschäfer
Al Cooper
Wang Qing
Heikki Krogerus
Geert Uytterhoeven