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2019-07-31serial: sh-sci: Fix TX DMA buffer flushing and workqueue racesGeert Uytterhoeven1-7/+15
[ Upstream commit 8493eab02608b0e82f67b892aa72882e510c31d0 ] When uart_flush_buffer() is called, the .flush_buffer() callback zeroes the tx_dma_len field. This may race with the work queue function handling transmit DMA requests: 1. If the buffer is flushed before the first DMA API call, dmaengine_prep_slave_single() may be called with a zero length, causing the DMA request to never complete, leading to messages like: rcar-dmac e7300000.dma-controller: Channel Address Error happen and, with debug enabled: sh-sci e6e88000.serial: sci_dma_tx_work_fn: ffff800639b55000: 0...0, cookie 126 and DMA timeouts. 2. If the buffer is flushed after the first DMA API call, but before the second, dma_sync_single_for_device() may be called with a zero length, causing the transmit data not to be flushed to RAM, and leading to stale data being output. Fix this by: 1. Letting sci_dma_tx_work_fn() return immediately if the transmit buffer is empty, 2. Extending the critical section to cover all DMA preparational work, so tx_dma_len stays consistent for all of it, 3. Using local copies of circ_buf.head and circ_buf.tail, to make sure they match the actual operation above. Reported-by: Eugeniu Rosca <erosca@de.adit-jv.com> Suggested-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Eugeniu Rosca <erosca@de.adit-jv.com> Tested-by: Eugeniu Rosca <erosca@de.adit-jv.com> Link: https://lore.kernel.org/r/20190624123540.20629-2-geert+renesas@glider.be Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-07-31serial: sh-sci: Terminate TX DMA during buffer flushingGeert Uytterhoeven1-2/+9
[ Upstream commit 775b7ffd7d6d5db320d99b0a485c51e04dfcf9f1 ] While the .flush_buffer() callback clears sci_port.tx_dma_len since commit 1cf4a7efdc71cab8 ("serial: sh-sci: Fix race condition causing garbage during shutdown"), it does not terminate a transmit DMA operation that may be in progress. Fix this by terminating any pending DMA operations, and resetting the corresponding cookie. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Eugeniu Rosca <erosca@de.adit-jv.com> Tested-by: Eugeniu Rosca <erosca@de.adit-jv.com> Link: https://lore.kernel.org/r/20190624123540.20629-3-geert+renesas@glider.be Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-07-31serial: mctrl_gpio: Check if GPIO property exisits before requesting itStefan Roese1-0/+14
[ Upstream commit d99482673f950817b30caf3fcdfb31179b050ce1 ] This patch adds a check for the GPIOs property existence, before the GPIO is requested. This fixes an issue seen when the 8250 mctrl_gpio support is added (2nd patch in this patch series) on x86 platforms using ACPI. Here Mika's comments from 2016-08-09: " I noticed that with v4.8-rc1 serial console of some of our Broxton systems does not work properly anymore. I'm able to see output but input does not work. I bisected it down to commit 4ef03d328769eddbfeca1f1c958fdb181a69c341 ("tty/serial/8250: use mctrl_gpio helpers"). The reason why it fails is that in ACPI we do not have names for GPIOs (except when _DSD is used) so we use the "idx" to index into _CRS GPIO resources. Now mctrl_gpio_init_noauto() goes through a list of GPIOs calling devm_gpiod_get_index_optional() passing "idx" of 0 for each. The UART device in Broxton has following (simplified) ACPI description: Device (URT4) { ... Name (_CRS, ResourceTemplate () { GpioIo (Exclusive, PullDefault, 0x0000, 0x0000, IoRestrictionOutputOnly, "\\_SB.GPO0", 0x00, ResourceConsumer) { 0x003A } GpioIo (Exclusive, PullDefault, 0x0000, 0x0000, IoRestrictionOutputOnly, "\\_SB.GPO0", 0x00, ResourceConsumer) { 0x003D } }) In this case it finds the first GPIO (0x003A which happens to be RX pin for that UART), turns it into GPIO which then breaks input for the UART device. This also breaks systems with bluetooth connected to UART (those typically have some GPIOs in their _CRS). Any ideas how to fix this? We cannot just drop the _CRS index lookup fallback because that would break many existing machines out there so maybe we can limit this to only DT enabled machines. Or alternatively probe if the property first exists before trying to acquire the GPIOs (using device_property_present()). " This patch implements the fix suggested by Mika in his statement above. Signed-off-by: Stefan Roese <sr@denx.de> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Tested-by: Yegor Yefremov <yegorslists@googlemail.com> Cc: Mika Westerberg <mika.westerberg@linux.intel.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Yegor Yefremov <yegorslists@googlemail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Giulio Benetti <giulio.benetti@micronovasrl.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-07-31tty: serial_core: Set port active bit in uart_port_activateSerge Semin1-1/+6
[ Upstream commit 13b18d35909707571af9539f7731389fbf0feb31 ] A bug was introduced by commit b3b576461864 ("tty: serial_core: convert uart_open to use tty_port_open"). It caused a constant warning printed into the system log regarding the tty and port counter mismatch: [ 21.644197] ttyS ttySx: tty_port_close_start: tty->count = 1 port count = 2 in case if session hangup was detected so the warning is printed starting from the second open-close iteration. Particularly the problem was discovered in situation when there is a serial tty device without hardware back-end being setup. It is considered by the tty-serial subsystems as a hardware problem with session hang up. In this case uart_startup() will return a positive value with TTY_IO_ERROR flag set in corresponding tty_struct instance. The same value will get passed to be returned from the activate() callback and then being returned from tty_port_open(). But since in this case tty_port_block_til_ready() isn't called the TTY_PORT_ACTIVE flag isn't set (while the method had been called before tty_port_open conversion was introduced and the rest of the subsystem code expected the bit being set in this case), which prevents the uart_hangup() method to perform any cleanups including the tty port counter setting to zero. So the next attempt to open/close the tty device will discover the counters mismatch. In order to fix the problem we need to manually set the TTY_PORT_ACTIVE flag in case if uart_startup() returned a positive value. In this case the hang up procedure will perform a full set of cleanup actions including the port ref-counter resetting. Fixes: b3b576461864 "tty: serial_core: convert uart_open to use tty_port_open" Signed-off-by: Serge Semin <fancer.lancer@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-07-31serial: uartps: Use the same dynamic major number for all portsShubhrajyoti Datta1-2/+3
[ Upstream commit ab262666018de6f4e206b021386b93ed0c164316 ] Let kernel to find out major number dynamically for the first device and then reuse it for other instances. This fixes the issue that each uart is registered with a different major number. After the patch: crw------- 1 root root 253, 0 Jun 10 08:31 /dev/ttyPS0 crw--w---- 1 root root 253, 1 Jan 1 1970 /dev/ttyPS1 Fixes: 024ca329bfb9 ("serial: uartps: Register own uart console and driver structures") Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-07-31serial: imx: fix locking in set_termios()Sergey Organov1-10/+13
[ Upstream commit 4e828c3e09201512be5ee162393f334321f7cf01 ] imx_uart_set_termios() called imx_uart_rts_active(), or imx_uart_rts_inactive() before taking port->port.lock. As a consequence, sport->port.mctrl that these functions modify could have been changed without holding port->port.lock. Moved locking of port->port.lock above the calls to fix the issue. Signed-off-by: Sergey Organov <sorganov@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-07-31sunhv: Fix device naming inconsistency between sunhv_console and sunhv_regJohn Paul Adrian Glaubitz1-1/+1
[ Upstream commit 07a6d63eb1b54b5fb38092780fe618dfe1d96e23 ] In d5a2aa24, the name in struct console sunhv_console was changed from "ttyS" to "ttyHV" while the name in struct uart_ops sunhv_pops remained unchanged. This results in the hypervisor console device to be listed as "ttyHV0" under /proc/consoles while the device node is still named "ttyS0": root@osaka:~# cat /proc/consoles ttyHV0 -W- (EC p ) 4:64 tty0 -WU (E ) 4:1 root@osaka:~# readlink /sys/dev/char/4:64 ../../devices/root/f02836f0/f0285690/tty/ttyS0 root@osaka:~# This means that any userland code which tries to determine the name of the device file of the hypervisor console device can not rely on the information provided by /proc/consoles. In particular, booting current versions of debian- installer inside a SPARC LDOM will fail with the installer unable to determine the console device. After renaming the device in struct uart_ops sunhv_pops to "ttyHV" as well, the inconsistency is fixed and it is possible again to determine the name of the device file of the hypervisor console device by reading the contents of /proc/console: root@osaka:~# cat /proc/consoles ttyHV0 -W- (EC p ) 4:64 tty0 -WU (E ) 4:1 root@osaka:~# readlink /sys/dev/char/4:64 ../../devices/root/f02836f0/f0285690/tty/ttyHV0 root@osaka:~# With this change, debian-installer works correctly when installing inside a SPARC LDOM. Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-07-31serial: 8250: Fix TX interrupt handling conditionRautkoski Kimmo EXT1-1/+2
[ Upstream commit db1b5bc047b3cadaedab3826bba82c3d9e023c4b ] Interrupt handler checked THRE bit (transmitter holding register empty) in LSR to detect if TX fifo is empty. In case when there is only receive interrupts the TX handling got called because THRE bit in LSR is set when there is no transmission (FIFO empty). TX handling caused TX stop, which in RS-485 half-duplex mode actually resets receiver FIFO. This is not desired during reception because of possible data loss. The fix is to check if THRI is set in IER in addition of the TX fifo status. THRI in IER is set when TX is started and cleared when TX is stopped. This ensures that TX handling is only called when there is really transmission on going and an interrupt for THRE and not when there are only RX interrupts. Signed-off-by: Kimmo Rautkoski <ext-kimmo.rautkoski@vaisala.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-07-31tty: serial: msm_serial: avoid system lockup conditionJorge Ramirez-Ortiz1-0/+4
[ Upstream commit ba3684f99f1b25d2a30b6956d02d339d7acb9799 ] The function msm_wait_for_xmitr can be taken with interrupts disabled. In order to avoid a potential system lockup - demonstrated under stress testing conditions on SoC QCS404/5 - make sure we wait for a bounded amount of time. Tested on SoC QCS404. Signed-off-by: Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-07-31tty/serial: digicolor: Fix digicolor-usart already registered warningKefeng Wang1-1/+5
[ Upstream commit c7ad9ba0611c53cfe194223db02e3bca015f0674 ] When modprobe/rmmod/modprobe module, if platform_driver_register() fails, the kernel complained, proc_dir_entry 'driver/digicolor-usart' already registered WARNING: CPU: 1 PID: 5636 at fs/proc/generic.c:360 proc_register+0x19d/0x270 Fix this by adding uart_unregister_driver() when platform_driver_register() fails. Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Acked-by: Baruch Siach <baruch@tkos.co.il> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-07-31tty: serial: cpm_uart - fix init when SMC is relocatedChristophe Leroy1-6/+11
[ Upstream commit 06aaa3d066db87e8478522d910285141d44b1e58 ] SMC relocation can also be activated earlier by the bootloader, so the driver's behaviour cannot rely on selected kernel config. When the SMC is relocated, CPM_CR_INIT_TRX cannot be used. But the only thing CPM_CR_INIT_TRX does is to clear the rstate and tstate registers, so this can be done manually, even when SMC is not relocated. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Fixes: 9ab921201444 ("cpm_uart: fix non-console port startup bug") Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-07-31tty: max310x: Fix invalid baudrate divisors calculatorSerge Semin1-20/+31
[ Upstream commit 35240ba26a932b279a513f66fa4cabfd7af55221 ] Current calculator doesn't do it' job quite correct. First of all the max310x baud-rates generator supports the divisor being less than 16. In this case the x2/x4 modes can be used to double or quadruple the reference frequency. But the current baud-rate setter function just filters all these modes out by the first condition and setups these modes only if there is a clocks-baud division remainder. The former doesn't seem right at all, since enabling the x2/x4 modes causes the line noise tolerance reduction and should be only used as a last resort to enable a requested too high baud-rate. Finally the fraction is supposed to be calculated from D = Fref/(c*baud) formulae, but not from D % 16, which causes the precision loss. So to speak the current baud-rate calculator code works well only if the baud perfectly fits to the uart reference input frequency. Lets fix the calculator by implementing the algo fully compliant with the fractional baud-rate generator described in the datasheet: D = Fref / (c*baud), where c={16,8,4} is the x1/x2/x4 rate mode respectively, Fref - reference input frequency. The divisor fraction is calculated from the same formulae, but making sure it is found with a resolution of 0.0625 (four bits). Signed-off-by: Serge Semin <fancer.lancer@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-07-14Revert "serial: 8250: Don't service RX FIFO if interrupts are disabled"Oliver Barta1-2/+1
commit 3f2640ed7be838c3f05c0d2b0f7c7508e7431e48 upstream. This reverts commit 2e9fe539108320820016f78ca7704a7342788380. Reading LSR unconditionally but processing the error flags only if UART_IIR_RDI bit was set before in IIR may lead to a loss of transmission error information on UARTs where the transmission error flags are cleared by a read of LSR. Information are lost in case an error is detected right before the read of LSR while processing e.g. an UART_IIR_THRI interrupt. Signed-off-by: Oliver Barta <o.barta89@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Fixes: 2e9fe5391083 ("serial: 8250: Don't service RX FIFO if interrupts are disabled") Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21tty: max310x: Fix external crystal register setupJoe Burmeister1-1/+1
The datasheet states: Bit 4: ClockEnSet the ClockEn bit high to enable an external clocking (crystal or clock generator at XIN). Set the ClockEn bit to 0 to disable clocking Bit 1: CrystalEnSet the CrystalEn bit high to enable the crystal oscillator. When using an external clock source at XIN, CrystalEn must be set low. The bit 4, MAX310X_CLKSRC_EXTCLK_BIT, should be set and was not. This was required to make the MAX3107 with an external crystal on our board able to send or receive data. Signed-off-by: Joe Burmeister <joe.burmeister@devtank.co.uk> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21serial: sh-sci: disable DMA for uart_consoleGeorge G. Davis1-0/+7
As noted in commit 84b40e3b57ee ("serial: 8250: omap: Disable DMA for console UART"), UART console lines use low-level PIO only access functions which will conflict with use of the line when DMA is enabled, e.g. when the console line is also used for systemd messages. So disable DMA support for UART console lines. Reported-by: Michael Rodin <mrodin@de.adit-jv.com> Link: https://patchwork.kernel.org/patch/10929511/ Tested-by: Eugeniu Rosca <erosca@de.adit-jv.com> Reviewed-by: Simon Horman <horms+renesas@verge.net.au> Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Cc: stable@vger.kernel.org Signed-off-by: George G. Davis <george_davis@mentor.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21serial: imx: remove log spamming error messageSascha Hauer1-1/+0
Each time the DMA engine signals a transaction error the driver prints a message at error level. Getting transaction errors is pretty much expected on baudrate mismatches and the correspoding error counters are increased in this case properly. Remove the error message which is possibly repeated at a very high rate which can lock up the whole system. Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Reviewed-by: Fabio Estevam <festevam@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21tty: serial: msm_serial: Fix XON/XOFFJorge Ramirez-Ortiz1-1/+4
When the tty layer requests the uart to throttle, the current code executing in msm_serial will trigger "Bad mode in Error Handler" and generate an invalid stack frame in pstore before rebooting (that is if pstore is indeed configured: otherwise the user shall just notice a reboot with no further information dumped to the console). This patch replaces the PIO byte accessor with the word accessor already used in PIO mode. Fixes: 68252424a7c7 ("tty: serial: msm: Support big-endian CPUs") Cc: stable@vger.kernel.org Signed-off-by: Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@linaro.org> Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org> Reviewed-by: Stephen Boyd <swboyd@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-09Merge tag 'dmaengine-5.2-rc1' of git://git.infradead.org/users/vkoul/slave-dmaLinus Torvalds1-2/+2
Pull dmaengine updates from Vinod Koul: - Updates to stm32 dma residue calculations - Interleave dma capability to axi-dmac and support for ZynqMP arch - Rework of channel assignment for rcar dma - Debugfs for pl330 driver - Support for Tegra186/Tegra194, refactoring for new chips and support for pause/resume - Updates to axi-dmac, bcm2835, fsl-edma, idma64, imx-sdma, rcar-dmac, stm32-dma etc - dev_get_drvdata() updates on few drivers * tag 'dmaengine-5.2-rc1' of git://git.infradead.org/users/vkoul/slave-dma: (34 commits) dmaengine: tegra210-adma: restore channel status dmaengine: tegra210-dma: free dma controller in remove() dmaengine: tegra210-adma: add pause/resume support dmaengine: tegra210-adma: add support for Tegra186/Tegra194 Documentation: DT: Add compatibility binding for Tegra186 dmaengine: tegra210-adma: prepare for supporting newer Tegra chips dmaengine: at_xdmac: remove a stray bottom half unlock dmaengine: fsl-edma: Adjust indentation dmaengine: fsl-edma: Fix typo in Vybrid name dmaengine: stm32-dma: fix residue calculation in stm32-dma dmaengine: nbpfaxi: Use dev_get_drvdata() dmaengine: bcm-sba-raid: Use dev_get_drvdata() dmaengine: stm32-dma: Fix unsigned variable compared with zero dmaengine: stm32-dma: use platform_get_irq() dmaengine: rcar-dmac: Update copyright information dmaengine: imx-sdma: Only check ratio on parts that support 1:1 dmaengine: xgene-dma: fix spelling mistake "descripto" -> "descriptor" dmaengine: idma64: Move driver name to the header dmaengine: bcm2835: Drop duplicate capability setting. dmaengine: pl330: _stop: clear interrupt status ...
2019-05-08Merge tag 'tty-5.2-rc1' of ↵Linus Torvalds17-80/+2404
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty Pull tty/serial updates from Greg KH: "Here is the "big" set of tty/serial driver patches for 5.2-rc1. It's really pretty small, not much happening in this portion of the kernel at the moment. When the "highlight" is the movement of the documentation from .txt to .rst files, it's a good merge window. There's a number of small fixes and updates over the various serial drivers, and a new "tty null" driver for those embedded systems that like to make things even smaller and not break things. All of these have been in linux-next for a while with no reported issues" * tag 'tty-5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (45 commits) tty: serial: add driver for the SiFive UART dt-bindings: serial: add documentation for the SiFive UART driver serial: uartps: Add support for cts-override dt-bindings: xilinx-uartps: Add support for cts-override serial: milbeaut_usio: Fix error handling in probe and remove tty: rocket: deprecate the rp_ioctl tty: rocket: Remove RCPK_GET_STRUCT ioctl tty: update obsolete termios comment tty: serial_core: fix error code returned by uart_register_driver() serial: 8250-mtk: modify baudrate setting serial: 8250-mtk: add follow control docs: serial: convert docs to ReST and rename to *.rst serial: 8250_exar: Adjust IOT2000 matching TTY: serial_core, add ->install serial: Fix using plain integer instead of Null pointer tty:serial_core: Spelling mistake tty: Add NULL TTY driver tty: vt: keyboard: Allow Unicode compose base char Revert "tty: fix NULL pointer issue when tty_port ops is not set" serial: Add Milbeaut serial control ...
2019-05-07Merge tag 'arm64-mmiowb' of ↵Linus Torvalds2-2/+0
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull mmiowb removal from Will Deacon: "Remove Mysterious Macro Intended to Obscure Weird Behaviours (mmiowb()) Remove mmiowb() from the kernel memory barrier API and instead, for architectures that need it, hide the barrier inside spin_unlock() when MMIO has been performed inside the critical section. The only relatively recent changes have been addressing review comments on the documentation, which is in a much better shape thanks to the efforts of Ben and Ingo. I was initially planning to split this into two pull requests so that you could run the coccinelle script yourself, however it's been plain sailing in linux-next so I've just included the whole lot here to keep things simple" * tag 'arm64-mmiowb' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (23 commits) docs/memory-barriers.txt: Update I/O section to be clearer about CPU vs thread docs/memory-barriers.txt: Fix style, spacing and grammar in I/O section arch: Remove dummy mmiowb() definitions from arch code net/ethernet/silan/sc92031: Remove stale comment about mmiowb() i40iw: Redefine i40iw_mmiowb() to do nothing scsi/qla1280: Remove stale comment about mmiowb() drivers: Remove explicit invocations of mmiowb() drivers: Remove useless trailing comments from mmiowb() invocations Documentation: Kill all references to mmiowb() riscv/mmiowb: Hook up mmwiob() implementation to asm-generic code powerpc/mmiowb: Hook up mmwiob() implementation to asm-generic code ia64/mmiowb: Add unconditional mmiowb() to arch_spin_unlock() mips/mmiowb: Add unconditional mmiowb() to arch_spin_unlock() sh/mmiowb: Add unconditional mmiowb() to arch_spin_unlock() m68k/io: Remove useless definition of mmiowb() nds32/io: Remove useless definition of mmiowb() x86/io: Remove useless definition of mmiowb() arm64/io: Remove useless definition of mmiowb() ARM/io: Remove useless definition of mmiowb() mmiowb: Hook up mmiowb helpers to spinlocks and generic I/O accessors ...
2019-04-29tty: serial: add driver for the SiFive UARTPaul Walmsley3-0/+1081
Add a serial driver for the SiFive UART, found on SiFive FU540 devices (among others). The underlying serial IP block is relatively basic, and currently does not support serial break detection. Further information on the IP block can be found in the documentation and Chisel sources: https://static.dev.sifive.com/FU540-C000-v1.0.pdf https://github.com/sifive/sifive-blocks/tree/master/src/main/scala/devices/uart This driver was written in collaboration with Wesley Terpstra <wesley@sifive.com>. Tested on a SiFive HiFive Unleashed A00 board, using BBL and the open- source FSBL (using a DT file based on what's targeted for mainline). This revision incorporates changes based on comments by Julia Lawall <julia.lawall@lip6.fr>, Emil Renner Berthing <kernel@esmil.dk>, and Andreas Schwab <schwab@suse.de>. Thanks also to Andreas for testing the driver with his userspace and reporting a bug with the set_termios implementation. Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com> Signed-off-by: Paul Walmsley <paul@pwsan.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jslaby@suse.com> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Wesley Terpstra <wesley@sifive.com> Cc: linux-serial@vger.kernel.org Cc: linux-riscv@lists.infradead.org Cc: linux-kernel@vger.kernel.org Cc: Julia Lawall <julia.lawall@lip6.fr> Cc: Emil Renner Berthing <kernel@esmil.dk> Cc: Andreas Schwab <schwab@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-29serial: uartps: Add support for cts-overrideShubhrajyoti Datta1-0/+12
Having flow is configurable. Add support for the same by checking for cts-override. Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-29serial: milbeaut_usio: Fix error handling in probe and removeWei Yongjun1-8/+1
devm_clk_get() is used so there is no reason to explicitly call clk_put() in probe or remove functions. Also remove duplicate assign for port->membase. Fixes: ba44dc043004 ("serial: Add Milbeaut serial control") Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com> Tested-by: Sugaya Taichi <sugaya.taichi@socionext.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-25tty: serial_core: fix error code returned by uart_register_driver()Sergey Organov1-2/+2
uart_register_driver() returned -ENOMEM on any error, even when tty_register_driver() call returned another one, such as -EBUSY. Signed-off-by: Sergey Organov <sorganov@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-25serial: 8250-mtk: modify baudrate settingLong Cheng1-0/+102
In termios function, add Fractional divider to adjust baudrate. Signed-off-by: Long Cheng <long.cheng@mediatek.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-25serial: 8250-mtk: add follow controlLong Cheng1-23/+37
Add SW and HW follow control function. Signed-off-by: Long Cheng <long.cheng@mediatek.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-25docs: serial: convert docs to ReST and rename to *.rstMauro Carvalho Chehab1-1/+1
The converted files are focused at the Kernel internal API, so, this is a good candidate for the kernel API set of books. The conversion is actually: - add blank lines and identation in order to identify paragraphs; - fix tables markups; - add some lists markups; - mark literal blocks; - adjust title markups. At its new index.rst, let's add a :orphan: while this is not linked to the main index.rst file, in order to avoid build warnings. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-25serial: 8250_exar: Adjust IOT2000 matchingSu Bao Cheng1-2/+5
Since there are more IOT2040 variants with identical hardware but different asset tags, the asset tag matching should be adjusted to support them. As only the IOT2040 variants have the Exar chip on board, matching on their board name is enough. In the future there will be no other devices with the "SIMATIC IOT2000" DMI board name but different hardware. Signed-off-by: Su Bao Cheng <baocheng.su@siemens.com> Reviewed-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-25TTY: serial_core, add ->installJiri Slaby1-11/+13
We need to compute the uart state only on the first open. This is usually what is done in the ->install hook. serial_core used to do this in ->open on every open. So move it to ->install. As a side effect, it ensures the state is set properly in the window after tty_init_dev is called, but before uart_open. This fixes a bunch of races between tty_open and flush_to_ldisc we were dealing with recently. One of such bugs was attempted to fix in commit fedb5760648a (serial: fix race between flush_to_ldisc and tty_open), but it only took care of a couple of functions (uart_start and uart_unthrottle). I was able to reproduce the crash on a SLE system, but in uart_write_room which is also called from flush_to_ldisc via process_echoes. I was *unable* to reproduce the bug locally. It is due to having this patch in my queue since 2012! general protection fault: 0000 [#1] SMP KASAN PTI CPU: 1 PID: 5 Comm: kworker/u4:0 Tainted: G L 4.12.14-396-default #1 SLE15-SP1 (unreleased) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-0-ga698c89-prebuilt.qemu.org 04/01/2014 Workqueue: events_unbound flush_to_ldisc task: ffff8800427d8040 task.stack: ffff8800427f0000 RIP: 0010:uart_write_room+0xc4/0x590 RSP: 0018:ffff8800427f7088 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 000000000000002f RSI: 00000000000000ee RDI: ffff88003888bd90 RBP: ffffffffb9545850 R08: 0000000000000001 R09: 0000000000000400 R10: ffff8800427d825c R11: 000000000000006e R12: 1ffff100084fee12 R13: ffffc900004c5000 R14: ffff88003888bb28 R15: 0000000000000178 FS: 0000000000000000(0000) GS:ffff880043300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000561da0794148 CR3: 000000000ebf4000 CR4: 00000000000006e0 Call Trace: tty_write_room+0x6d/0xc0 __process_echoes+0x55/0x870 n_tty_receive_buf_common+0x105e/0x26d0 tty_ldisc_receive_buf+0xb7/0x1c0 tty_port_default_receive_buf+0x107/0x180 flush_to_ldisc+0x35d/0x5c0 ... 0 in rbx means tty->driver_data is NULL in uart_write_room. 0x178 is tried to be dereferenced (0x178 >> 3 is 0x2f in rdx) at uart_write_room+0xc4. 0x178 is exactly (struct uart_state *)NULL->refcount used in uart_port_lock from uart_write_room. So revert the upstream commit here as my local patch should fix the whole family. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Li RongQing <lirongqing@baidu.com> Cc: Wang Li <wangli39@baidu.com> Cc: Zhang Yu <zhangyu31@baidu.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-25serial: Fix using plain integer instead of Null pointerSugaya Taichi1-1/+1
Fix build warning that using plain integer as Null pointer. This is reported by kbuild test robot. Fixes: ba44dc043004 ("serial: Add Milbeaut serial control") Signed-off-by: Sugaya Taichi <sugaya.taichi@socionext.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-22Merge 5.1-rc6 into tty-nextGreg Kroah-Hartman2-3/+7
We want the serial/tty fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-19sc16is7xx: put err_spi and err_i2c into correct #ifdefGuoqing Jiang1-2/+2
err_spi is only called within SERIAL_SC16IS7XX_SPI while err_i2c is called inside SERIAL_SC16IS7XX_I2C. So we need to put err_spi and err_i2c into each #ifdef accordingly. This change fixes ("sc16is7xx: move label 'err_spi' to correct section"). Signed-off-by: Guoqing Jiang <gqjiang@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-16tty:serial_core: Spelling mistakeHariprasad Kelam1-1/+1
fix spelling mistake "overriden" -> "overridden" This fix resolves warning reported by checkpatch tool. Signed-off-by: Hariprasad Kelam <hariprasad.kelam@gmail.com> Reviewed-by: Mukesh Ojha <mojha@codeaurora.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-16sc16is7xx: move label 'err_spi' to correct sectionGuoqing Jiang1-0/+2
err_spi is used when SERIAL_SC16IS7XX_SPI is enabled, so make the label only available under SERIAL_SC16IS7XX_SPI option. Otherwise, the below warning appears. drivers/tty/serial/sc16is7xx.c:1523:1: warning: label ‘err_spi’ defined but not used [-Wunused-label] err_spi: ^~~~~~~ Signed-off-by: Guoqing Jiang <gqjiang@suse.com> Fixes: ac0cdb3d9901 ("sc16is7xx: missing unregister/delete driver on error in sc16is7xx_init()") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-16serial: sh-sci: Fix HSCIF RX sampling point adjustmentGeert Uytterhoeven1-1/+1
The calculation of the sampling point has min() and max() exchanged. Fix this by using the clamp() helper instead. Fixes: 63ba1e00f178a448 ("serial: sh-sci: Support for HSCIF RX sampling point adjustment") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Ulrich Hecht <uli+renesas@fpond.eu> Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Acked-by: Dirk Behme <dirk.behme@de.bosch.com> Cc: stable <stable@vger.kernel.org> Reviewed-by: Simon Horman <horms+renesas@verge.net.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-16serial: sh-sci: Fix HSCIF RX sampling point calculationGeert Uytterhoeven1-1/+3
There are several issues with the formula used for calculating the deviation from the intended rate: 1. While min_err and last_stop are signed, srr and baud are unsigned. Hence the signed values are promoted to unsigned, which will lead to a bogus value of deviation if min_err is negative, 2. Srr is the register field value, which is one less than the actual sampling rate factor, 3. The divisions do not use rounding. Fix this by casting unsigned variables to int, adding one to srr, and using a single DIV_ROUND_CLOSEST(). Fixes: 63ba1e00f178a448 ("serial: sh-sci: Support for HSCIF RX sampling point adjustment") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Mukesh Ojha <mojha@codeaurora.org> Cc: stable <stable@vger.kernel.org> Reviewed-by: Ulrich Hecht <uli+renesas@fpond.eu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-16serial: Add Milbeaut serial controlSugaya Taichi3-0/+648
Add Milbeaut serial control including earlycon and console. Signed-off-by: Sugaya Taichi <sugaya.taichi@socionext.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-16tty: remove redundant 'default n' from Kconfig-sBartlomiej Zolnierkiewicz1-3/+0
'default n' is the default value for any bool or tristate Kconfig setting so there is no need to write it explicitly. Also since commit f467c5640c29 ("kconfig: only write '# CONFIG_FOO is not set' for visible symbols") the Kconfig behavior is the same regardless of 'default n' being present or not: ... One side effect of (and the main motivation for) this change is making the following two definitions behave exactly the same: config FOO bool config FOO bool default n With this change, neither of these will generate a '# CONFIG_FOO is not set' line (assuming FOO isn't selected/implied). That might make it clearer to people that a bare 'default n' is redundant. ... Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-16serial: sprd: Fix a copy-paste err in sprd_request_dma()YueHaibing1-1/+1
when dma_request_chan rx_dma fails, dev_err log should print rx_dma err log. Signed-off-by: YueHaibing <yuehaibing@huawei.com> Reviewed-by: Mukesh Ojha <mojha@codeaurora.org> Reviewed-by: Baolin Wang <baolin.wang@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-08drivers: Remove explicit invocations of mmiowb()Will Deacon2-2/+0
mmiowb() is now implied by spin_unlock() on architectures that require it, so there is no reason to call it from driver code. This patch was generated using coccinelle: @mmiowb@ @@ - mmiowb(); and invoked as: $ for d in drivers include/linux/qed sound; do \ spatch --include-headers --sp-file mmiowb.cocci --dir $d --in-place; done NOTE: mmiowb() has only ever guaranteed ordering in conjunction with spin_unlock(). However, pairing each mmiowb() removal in this patch with the corresponding call to spin_unlock() is not at all trivial, so there is a small chance that this change may regress any drivers incorrectly relying on mmiowb() to order MMIO writes between CPUs using lock-free synchronisation. If you've ended up bisecting to this commit, you can reintroduce the mmiowb() calls using wmb() instead, which should restore the old behaviour on all architectures other than some esoteric ia64 systems. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-04tty: fix up a few remaining files without SPDX identifiersGreg Kroah-Hartman2-0/+2
There were a few straggling files under drivers/tty/ that did not have any SPDX identifier either because they entered the tree recently, or they somehow missed the mass-tagging of commit b24413180f56 ("License cleanup: add SPDX GPL-2.0 license identifier to files with no license") This commit follows the same rule as b24413180f56 ("License cleanup: add SPDX GPL-2.0 license identifier to files with no license") where files without any specified license in them fall under GPL-2.0 as the correct license for the individual file. Add that identifier to these remaining files so that we don't have to guess at the license of them in the future. Cc: Jiri Slaby <jslaby@suse.com> Cc: "David S. Miller" <davem@davemloft.net> Reviewed-by: Mukesh Ojha <mojha@codeaurora.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-04tty: add SPDX identifiers to Kconfig and MakefilesGreg Kroah-Hartman4-0/+4
There were a few Kconfig and Makefiles under drivers/tty/ that were missing a SPDX identifier. Fix that up so that automated tools can properly classify all kernel source files. Cc: Jiri Slaby <jslaby@suse.com> Cc: Jiri Kosina <jikos@kernel.org> Cc: Rob Herring <robh@kernel.org> Acked-by: David Sterba <dsterba@suse.com> Reviewed-by: Mukesh Ojha <mojha@codeaurora.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-01Merge 5.1-rc3 into tty-nextGreg Kroah-Hartman9-46/+69
We want the tty/serial fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-27serial: sc16is7xx: Drop of_match_ptr() useAndy Shevchenko1-3/+2
There is an ACPI method to enumerate such devices via specific ACPI ID and use of compatible strings. It will not work for the drivers which have no OF match ID table present. Reported-by: Georgii Staroselskii <georgii.staroselskii@emlid.com> Tested-By: Georgii Staroselskii <georgii.staroselskii@emlid.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-27serial: sc16is7xx: Switch to use device_get_match_data()Andy Shevchenko1-13/+5
Instead of open coded variants, switch to direct use of device_get_match_data(). Tested-By: Georgii Staroselskii <georgii.staroselskii@emlid.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-27serial: sc16is7xx: Respect clock-frequency propertyAndy Shevchenko1-1/+10
If the property is provided and there are no other possibilities to detect UART clock frequency, use it as a fallback. Tested-By: Georgii Staroselskii <georgii.staroselskii@emlid.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-27serial: sprd: Add DMA mode supportLanqing Liu1-14/+426
Add DMA mode support for the Spreadtrum serial controller. Signed-off-by: Lanqing Liu <lanqing.liu@unisoc.com> Signed-off-by: Baolin Wang <baolin.wang@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-27serial: sprd: Add power management for the Spreadtrum serial controllerLanqing Liu1-4/+57
This patch adds power management for the Spreadtrum serial controller. Signed-off-by: Lanqing Liu <lanqing.liu@unisoc.com> Signed-off-by: Baolin Wang <baolin.wang@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-27serial: 8250_fintek: Make fintek_8250_set_termios staticYueHaibing1-2/+3
Fix sparse warning: drivers/tty/serial/8250/8250_fintek.c:306:6: warning: symbol 'fintek_8250_set_termios' was not declared. Should it be static? Signed-off-by: YueHaibing <yuehaibing@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-27Disable kgdboc failed by echo space to /sys/module/kgdboc/parameters/kgdbocWentao Wang1-1/+3
Echo "" to /sys/module/kgdboc/parameters/kgdboc will fail with "No such device” error. This is caused by function "configure_kgdboc" who init err to ENODEV when the config is empty (legal input) the code go out with ENODEV returned. Fixes: 2dd453168643 ("kgdboc: Fix restrict error") Signed-off-by: Wentao Wang <witallwang@gmail.com> Cc: stable <stable@vger.kernel.org> Acked-by: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>