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path: root/drivers/tty/serial
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2017-06-29serial: 8250: 8250_omap: Fix race b/w dma completion and RX timeoutVignesh R
DMA RX completion handler for UART is called from a tasklet and hence may be delayed depending on the system load. In meanwhile, there may be RX timeout interrupt which can get serviced first before DMA RX completion handler is executed for the completed transfer. omap_8250_rx_dma_flush() which is called on RX timeout interrupt makes sure that the DMA RX buffer is pushed and then the FIFO is drained and also queues a new DMA request. But, when DMA RX completion handler executes, it will erroneously flush the currently queued DMA transfer which sometimes results in data corruption and double queueing of DMA RX requests. Fix this by checking whether RX completion is for the currently queued transfer or not. And also hold port lock when in DMA completion to avoid race wrt RX timeout handler preempting it. Signed-off-by: Vignesh R <vigneshr@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-29serial: 8250: Fix THRE flag usage for CAP_MINIPhil Elwell
The BCM2835 MINI UART has non-standard THRE semantics. Conventionally the bit means that the FIFO is empty (although there may still be a byte in the transmit register), but on 2835 it indicates that the FIFO is not full. This causes interrupts after every byte is transmitted, with the FIFO providing some interrupt latency tolerance. A consequence of this difference is that the usual strategy of writing multiple bytes into the TX FIFO after checking THRE once is unsafe. In the worst case of 7 bytes in the FIFO, writing 8 bytes loses all but the first since by then the FIFO is full. There is an HFIFO ("Hidden FIFO") capability that causes the transmit loop to terminate when both THRE and TEMT are set, i.e. when the TX block is completely idle. This is unnecessarily cautious, potentially causing gaps in transmission. Add a new conditional to the transmit loop, predicated on CAP_MINI, that exits when THRE is no longer set (the FIFO is full). This allows the FIFO to fill quickly but subsequent writes are paced by the transmission rate. Signed-off-by: Phil Elwell <phil@raspberrypi.org> Acked-by: Eric Anholt <eric@anholt.net> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-20gpio-exar/8250-exar: Fix passing in of parent PCI deviceJan Kiszka
This fixes reloading of the GPIO driver for the same platform device instance as created by the exar UART driver: First of all, the driver sets drvdata to its own value during probing and does not restore the original value on exit. But this won't help anyway as the core clears drvdata after the driver left. Set the platform device parent instead. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-06-20tty/serial: meson_uart: update to stable bindingsHelmut Klein
This patch handle the stable UART bindings but also keeps compatibility with the legacy non-stable bindings until all boards uses them. Reviewed-by: Jerome Brunet <jbrunet@baylibre.com> Signed-off-by: Helmut Klein <hgkr.klein@gmail.com> Signed-off-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-20serial: Delete dead code for CIR serial portsMatthias Brugger
Commit e4fda3a04275 ("serial: don't register CIR serial ports") adds a check for PORT_8250_CIR to serial8250_register_8250_port(). But the code isn't needed as the function never takes the branch when the port is CIR serial port. This patch deletes the dead code. Signed-off-by: Matthias Brugger <mbrugger@suse.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-20serial: sirf: make of_device_ids constArvind Yadav
of_device_ids are not supposed to change at runtime. All functions working with of_device_ids provided by <linux/of.h> work with const of_device_ids. So mark the non-const structs as const. Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-20serial/mpsc: switch to dma_alloc_attrsChristoph Hellwig
Use dma_alloc_attrs directly instead of the dma_alloc_noncoherent wrapper. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-20tty: serial: Add Actions Semi Owl UART earlyconAndreas Färber
This implements an earlycon for Actions Semi S500/S900 SoCs. Based on LeMaker linux-actions tree. Signed-off-by: Andreas Färber <afaerber@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-14tty/serial: atmel: make the driver DT onlyAlexandre Belloni
Now that AVR32 is gone, platform_data are not used to initialize the driver anymore, remove that path from the driver. Also remove the now unused struct atmel_uart_data. Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com> Acked-by: Richard Genoud <richard.genoud@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-14tty/serial: atmel: remove atmel_default_console_device handlingAlexandre Belloni
atmel_default_console_device was only used by AVR32, in particular arch/avr32/mach-at32ap/at32ap700x.c which is now gone. Remove it from the driver. Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com> Acked-by: Richard Genoud <richard.genoud@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-13serial: rate limit custom-speed deprecation noticeJohan Hovold
Contrary to what a comment claimed, the ASYNC_SPD flags and custom divisor can be set by a non-privileged user so rate limit the deprecation notice as was intended. Signed-off-by: Johan Hovold <johan@kernel.org> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-09serial: exar: Leave MPIOs as output for Commtech adaptersJan Kiszka
Commtech adapters apparently need the original setting as outputs, see https://marc.info/?l=linux-gpio&m=149557425201323&w=2. Account for that. Fixes: 7dea8165f1d6 ("serial: exar: Preconfigure xr17v35x MPIOs as output") Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-09tty/serial: atmel: Remove AVR32 bits from the driverAndy Shevchenko
AVR32 is gone. Now it's time to clean up the driver by removing leftovers that was used by AVR32 related code. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Richard Genoud <richard.genoud@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-03serial: uartps: Fix kernel doc warningsNava kishore Manne
This patch fixes the kernel doc warnings in the driver. Signed-off-by: Nava kishore Manne <navam@xilinx.com> Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-03serial: 8250_of: Add reset supportJoel Stanley
This adds the hooks for an optional reset controller in the 8250 device tree node. Signed-off-by: Joel Stanley <joel@jms.id.au> Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-03Fix serial console on SNI RM400 machinesThomas Bogendoerfer
sccnxp driver doesn't get the correct uart clock rate, if CONFIG_HAVE_CLOCK is disabled. Correct usage of clk API to make it work with/without it. Fixes: 90efa75f7ab0 (serial: sccnxp: Using CLK API for getting UART clock) Suggested-by: Russell King - ARM Linux <linux@armlinux.org.uk> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-29Merge 4.12-rc3 into tty-nextGreg Kroah-Hartman
We need the tty fixes/changes here to handle future work. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-25serial: altera_uart: call iounmap() at driver removeTobias Klauser
The driver calls ioremap() in the probe function but doesn't call iounmap() in the remove function correspondingly. Do so now. Follow commit 5c9d6abed9e0 ("serial: altera_jtaguart: adding iounmap()") Cc: Alexey Khoroshilov <khoroshilov@ispras.ru> Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-25serial: imx: ensure UCR3 and UFCR are setup correctlyUwe Kleine-König
Commit e61c38d85b73 ("serial: imx: setup DCEDTE early and ensure DCD and RI irqs to be off") has a flaw: While UCR3 and UFCR were modified using read-modify-write before it switched to write register values independent of the previous state. That's a good idea in principle (and that's why I did it) but needs more care. This patch reinstates read-modify-write for UFCR and for UCR3 ensures that RXDMUXSEL and ADNIMP are set for post imx1. Fixes: e61c38d85b73 ("serial: imx: setup DCEDTE early and ensure DCD and RI irqs to be off") Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Acked-by: Mika Penttilä <mika.penttila@nextfour.com> Tested-by: Mika Penttilä <mika.penttila@nextfour.com> Acked-by: Steve Twiss <stwiss.opensource@diasemi.com> Tested-by: Steve Twiss <stwiss.opensource@diasemi.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-24serial: 8250: Add CAP_MINI, set for bcm2835auxPhil Elwell
The AUX/mini-UART in the BCM2835 family of procesors is a cut-down 8250 clone. In particular it is lacking support for the following features: CSTOPB PARENB PARODD CMSPAR CS5 CS6 Add a new capability (UART_CAP_MINI) that exposes the restrictions to the user of the termios API by turning off the unsupported features in the request. N.B. It is almost possible to automatically discover the missing features by reading back the LCR register, but the CSIZE bits don't cooperate (contrary to the documentation, both bits are significant, but CS5 and CS6 are mapped to CS7) and the code is much longer. See: https://github.com/raspberrypi/linux/issues/1561 Signed-off-by: Phil Elwell <phil@raspberrypi.org> Acked-by: Eric Anholt <eric@anholt.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-24serial: sh-sci: Update warning message in sci_request_dma_chan()Geert Uytterhoeven
The commit below changed a function call from dma_request_slave_channel_compat() to dma_request_slave_channel(), but forgot to update the printed failure message. Fixes: 219fb0c1436e4893 ("serial: sh-sci: Remove the platform data dma slave rx/tx channel IDs") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-24serial: meson: hide an unused functionArnd Bergmann
The newly added meson_uart_enable_tx_engine function is only called from the console setup, not the runtime uart, which has an open-coded version of the same register access. This produces a harmless warning when the console code is disabled: drivers/tty/serial/meson_uart.c:127:13: error: 'meson_uart_enable_tx_engine' defined but not used [-Werror=unused-function] Let's move the function inside of the #ifdef to avoid the warning. Fixes: ba50f1df13c8 ("serial: meson: remove unneeded variable assignment in meson_serial_port_write") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: enable serdev supportJohan Hovold
Enable serdev support by using the new device-registration helpers. Reviewed-by: Rob Herring <robh@kernel.org> Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: core: fix crash in uart_suspend_portLucas Stach
With serdev we might end up with serial ports that have no cdev exported to userspace, as they are used as the bus interface to other devices. In that case serial_match_port() won't be able to find a matching tty_dev. Skip the irq wakeup enabling in that case, as serdev will make sure to keep the port active, as long as there are devices depending on it. Fixes: 8ee3fde04758 (tty_port: register tty ports with serdev bus) Signed-off-by: Lucas Stach <l.stach@pengutronix.de> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: ifx6x60: fix use-after-free on module unloadJohan Hovold
Make sure to deregister the SPI driver before releasing the tty driver to avoid use-after-free in the SPI remove callback where the tty devices are deregistered. Fixes: 72d4724ea54c ("serial: ifx6x60: Add modem power off function in the platform reboot process") Cc: stable <stable@vger.kernel.org> # 3.8 Cc: Jun Chen <jun.d.chen@intel.com> Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: altera_jtaguart: adding iounmap()Alexey Khoroshilov
The driver does ioremap(port->mapbase, ALTERA_JTAGUART_SIZE), but there is no any iounmap(). Found by Linux Driver Verification project (linuxtesting.org). Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru> Acked-by: Tobias Klauser <tklauser@distanz.ch> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: exar: Fix stuck MSIsJan Kiszka
After migrating 8250_exar to MSI in 172c33cb61da, we can get stuck without further interrupts because of the special wake-up event these chips send. They are only cleared by reading INT0. As we fail to do so during startup and shutdown, we can leave the interrupt line asserted, which is fatal with edge-triggered MSIs. Add the required reading of INT0 to startup and shutdown. Also account for the fact that a pending wake-up interrupt means we have to return 1 from exar_handle_irq. Drop the unneeded reading of INT1..3 along with this - those never reset anything. An alternative approach would have been disabling the wake-up interrupt. Unfortunately, this feature (REGB[17] = 1) is not available on the XR17D15X. Fixes: 172c33cb61da ("serial: exar: Enable MSI support") Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: efm32: Fix parity management in 'efm32_uart_console_get_options()'Christophe JAILLET
UARTn_FRAME_PARITY_ODD is 0x0300 UARTn_FRAME_PARITY_EVEN is 0x0200 So if the UART is configured for EVEN parity, it would be reported as ODD. Fix it by correctly testing if the 2 bits are set. Fixes: 3afbd89c9639 ("serial/efm32: add new driver") Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18drivers/tty: 8250: only call fintek_8250_probe when doing port I/OArd Biesheuvel
Commit fa01e2ca9f53 ("serial: 8250: Integrate Fintek into 8250_base") modified the probing logic for PNP0501 devices, to remove a collision between the generic 16550A driver and the Fintek driver, which reused the same ACPI _HID. The Fintek device probe is now incorporated into the common 8250 probe path, and gets called for all discovered 16550A compatible devices, including ones that are MMIO mapped rather than IO mapped. However, the Fintek driver assumes the port base is a I/O address, and proceeds to probe some arbitrary offsets above it. This is generally a wrong thing to do, but on ARM systems (having no native port I/O), this may result in faulting accesses of completely unrelated MMIO regions in the PCI I/O space. Given that this is at serial probe time, this results in hard to diagnose crashes at boot. So let's restrict the Fintek probe to devices that we know are using port I/O in the first place. Fixes: fa01e2ca9f53 ("serial: 8250: Integrate Fintek into 8250_base") Suggested-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Ricardo Ribalda <ricardo.ribalda@gmail.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: xilinx_uartps: Fix the error pathShubhrajyoti Datta
Fix the runtime calls in the error path. Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: meson: change interrupt description to tty nameHeiner Kallweit
Change interrupt description from driver name to tty name (e.g. ttyAML0). If multiple serial ports are enabled this allows to determine which interrupt belongs to which port in /proc/interrupts. Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: meson: remove use of flag UPF_IOREMAPHeiner Kallweit
Flag UPF_IOREMAP is used by the 8250 subsystem only, it's not used by the serial core. Therefore I don't see any benefit in using it here. In addition fix the order of calls in meson_uart_release_port. Unmapping needs to be done first, reversing call order in meson_uart_request_port. Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: meson: make use of uart_port member mapsizeHeiner Kallweit
Member mapsize of struct uart_port is meant to store the resource size. By using it we can get rid of meson_uart_res_size(). Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: meson: remove dead code in meson_uart_change_speedHeiner Kallweit
val is set in both branches of the if clause, therefore the two removed lines are dead code. Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: meson: remove unneeded variable assignment in meson_serial_port_writeHeiner Kallweit
There's no need to set AML_UART_TX_EN in each call to meson_serial_port_write. In addition to meson_uart_startup set this flag in meson_serial_console_setup and meson_serial_early_console_setup. Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: meson: fix setting number of stop bitsHeiner Kallweit
The stop bit value as to be or'ed, so far this worked only just by chance because AML_UART_STOP_BIN_1SB is 0. Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: pch_uart: use offset_in_page() macroGeliang Tang
Use offset_in_page() macro instead of open-coding. Signed-off-by: Geliang Tang <geliangtang@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18tty/serial: atmel: use offset_in_page() macroGeliang Tang
Use offset_in_page() macro instead of open-coding. Signed-off-by: Geliang Tang <geliangtang@gmail.com> Acked-by: Richard Genoud <richard.genoud@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: exar: Preconfigure xr17v35x MPIOs as outputJan Kiszka
This is the safe default for GPIOs with unknown external wiring. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18imx-serial: RX DMA startup latencyPeter Senna Tschudin
18a4208 introduced a change to reduce the RX DMA latency on the first reception when the serial port was opened for reading. However it was claiming a hardirq unsafe lock after a hardirq safe lock which is not allowed and causes lockdep to complain verbosely. This patch changes the code to always start RX DMA earlier, instead of relying on the flags used to open the serial port removing the code that was looking for the serial file flags. Signed-off-by: Peter Senna Tschudin <peter.senna@collabora.com> Tested-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: sh-sci: Move uart_register_driver call to device probeSjoerd Simons
uart_register_driver call binds the driver to a specific device node through tty_register_driver call. This should typically happen during device probe call. In a multiplatform scenario, it is possible that multiple serial drivers are part of the kernel. Currently the driver registration fails if multiple serial drivers with overlapping major/minor numbers are included. Signed-off-by: Sjoerd Simons <sjoerd.simons@collabora.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: pl010: Move uart_register_driver call to device probeSjoerd Simons
uart_register_driver call binds the driver to a specific device node through tty_register_driver call. This should typically happen during device probe call. In a multiplatform scenario, it is possible that multiple serial drivers are part of the kernel. Currently the driver registration fails if multiple serial drivers with overlapping major/minor numbers are included. Signed-off-by: Sjoerd Simons <sjoerd.simons@collabora.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: sh-sci: Fix race condition causing garbage during shutdownGeert Uytterhoeven
If DMA is enabled and used, a burst of old data may be seen on the serial console during "poweroff" or "reboot". uart_flush_buffer() clears the circular buffer, but sci_port.tx_dma_len is not reset. This leads to a circular buffer overflow, dumping (UART_XMIT_SIZE - sci_port.tx_dma_len) bytes. To fix this, add a .flush_buffer() callback that resets sci_port.tx_dma_len. Inspired by commit 31ca2c63fdc0aee7 ("tty/serial: atmel: fix race condition (TX+DMA)"). Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18drivers/serial: Add driver for Aspeed virtual UARTJeremy Kerr
This change adds a driver for the 16550-based Aspeed virtual UART device. We use a similar process to the of_serial driver for device probe, but expose some VUART-specific functions through sysfs too. The VUART is two UART 'front ends' connected by their FIFO (no actual serial line in between). One is on the BMC side (management controller) and one is on the host CPU side. This driver is for the BMC side. The sysfs files allow the BMC userspace, which owns the system configuration policy, to specify at what IO port and interrupt number the host side will appear to the host on the Host <-> BMC LPC bus. It could be different on a different system (though most of them use 3f8/4). OpenPOWER host firmware doesn't like it when the host-side of the VUART's FIFO is not drained. This driver only disables host TX discard mode when the port is in use. We set the VUART enabled bit when we bind to the device, and clear it on unbind. We don't want to do this on open/release, as the host may be using this bit to configure serial output modes, which is independent of whether the devices has been opened by BMC userspace. Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Signed-off-by: Joel Stanley <joel@jms.id.au> Acked-by: Rob Herring <robh@kernel.org> Reviewed-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: 8250: Add flag so drivers can avoid THRE probeJoel Stanley
The probing of THRE irq behaviour assumes the other end will be reading bytes out of the buffer in order to probe the port at driver init. In some cases the other end cannot be relied upon to read these bytes, so provide a flag for them to skip this step. Bit 19 was chosen as the flags are a int and the top bits are taken. Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: 8250_exar: Remove duplicate assignmentAndy Shevchenko
UPF_EXAR_EFR is set globally for each port enumerated by the driver. Thus, no need to repeat this in individual ->setup() hook. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: 8250: omap: Disable DMA for console UARTVignesh R
Kernel always writes log messages to console via serial8250_console_write()->serial8250_console_putchar() which directly accesses UART_TX register _without_ using DMA. But, if other processes like systemd using same UART port, then these writes are handled by a different code flow using 8250_omap driver where there is provision to use DMA. It seems that it is possible that both DMA and CPU might simultaneously put data to UART FIFO and lead to potential loss of data due to FIFO overflow and weird data corruption. This happens when both kernel console and userspace tries to write simultaneously to the same UART port. Therefore, disable DMA on kernel console port to avoid potential race between CPU and DMA. Signed-off-by: Vignesh R <vigneshr@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-10Merge tag 'hwparam-20170420' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs Pull hw lockdown support from David Howells: "Annotation of module parameters that configure hardware resources including ioports, iomem addresses, irq lines and dma channels. This allows a future patch to prohibit the use of such module parameters to prevent that hardware from being abused to gain access to the running kernel image as part of locking the kernel down under UEFI secure boot conditions. Annotations are made by changing: module_param(n, t, p) module_param_named(n, v, t, p) module_param_array(n, t, m, p) to: module_param_hw(n, t, hwtype, p) module_param_hw_named(n, v, t, hwtype, p) module_param_hw_array(n, t, hwtype, m, p) where the module parameter refers to a hardware setting hwtype specifies the type of the resource being configured. This can be one of: ioport Module parameter configures an I/O port iomem Module parameter configures an I/O mem address ioport_or_iomem Module parameter could be either (runtime set) irq Module parameter configures an I/O port dma Module parameter configures a DMA channel dma_addr Module parameter configures a DMA buffer address other Module parameter configures some other value Note that the hwtype is compile checked, but not currently stored (the lockdown code probably won't require it). It is, however, there for future use. A bonus is that the hwtype can also be used for grepping. The intention is for the kernel to ignore or reject attempts to set annotated module parameters if lockdown is enabled. This applies to options passed on the boot command line, passed to insmod/modprobe or direct twiddling in /sys/module/ parameter files. The module initialisation then needs to handle the parameter not being set, by (1) giving an error, (2) probing for a value or (3) using a reasonable default. What I can't do is just reject a module out of hand because it may take a hardware setting in the module parameters. Some important modules, some ipmi stuff for instance, both probe for hardware and allow hardware to be manually specified; if the driver is aborts with any error, you don't get any ipmi hardware. Further, trying to do this entirely in the module initialisation code doesn't protect against sysfs twiddling. [!] Note that in and of itself, this series of patches should have no effect on the the size of the kernel or code execution - that is left to a patch in the next series to effect. It does mark annotated kernel parameters with a KERNEL_PARAM_FL_HWPARAM flag in an already existing field" * tag 'hwparam-20170420' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs: (38 commits) Annotate hardware config module parameters in sound/pci/ Annotate hardware config module parameters in sound/oss/ Annotate hardware config module parameters in sound/isa/ Annotate hardware config module parameters in sound/drivers/ Annotate hardware config module parameters in fs/pstore/ Annotate hardware config module parameters in drivers/watchdog/ Annotate hardware config module parameters in drivers/video/ Annotate hardware config module parameters in drivers/tty/ Annotate hardware config module parameters in drivers/staging/vme/ Annotate hardware config module parameters in drivers/staging/speakup/ Annotate hardware config module parameters in drivers/staging/media/ Annotate hardware config module parameters in drivers/scsi/ Annotate hardware config module parameters in drivers/pcmcia/ Annotate hardware config module parameters in drivers/pci/hotplug/ Annotate hardware config module parameters in drivers/parport/ Annotate hardware config module parameters in drivers/net/wireless/ Annotate hardware config module parameters in drivers/net/wan/ Annotate hardware config module parameters in drivers/net/irda/ Annotate hardware config module parameters in drivers/net/hamradio/ Annotate hardware config module parameters in drivers/net/ethernet/ ...
2017-05-08Merge tag 'tty-4.12-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty Pull tty/serial updates from Greg KH: "Here is the "big" TTY/Serial patch updates for 4.12-rc1 Not a lot of new things here, the normal number of serial driver updates and additions, tiny bugs fixed, and some core files split up to make future changes a bit easier for Nicolas's "tiny-tty" work. All of these have been in linux-next for a while" * tag 'tty-4.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (62 commits) serial: small Makefile reordering tty: split job control support into a file of its own tty: move baudrate handling code to a file of its own console: move console_init() out of tty_io.c serial: 8250_early: Add earlycon support for Palmchip UART tty: pl011: use "qdf2400_e44" as the earlycon name for QDF2400 E44 vt: make mouse selection of non-ASCII consistent vt: set mouse selection word-chars to gpm's default imx-serial: Reduce RX DMA startup latency when opening for reading serial: omap: suspend device on probe errors serial: omap: fix runtime-pm handling on unbind tty: serial: omap: add UPF_BOOT_AUTOCONF flag for DT init serial: samsung: Remove useless spinlock serial: samsung: Add missing checks for dma_map_single failure serial: samsung: Use right device for DMA-mapping calls serial: imx: setup DCEDTE early and ensure DCD and RI irqs to be off tty: fix comment typo s/repsonsible/responsible/ tty: amba-pl011: Fix spurious TX interrupts serial: xuartps: Enable clocks in the pm disable case also serial: core: Re-use struct uart_port {name} field ...
2017-05-08format-security: move static strings to constKees Cook
While examining output from trial builds with -Wformat-security enabled, many strings were found that should be defined as "const", or as a char array instead of char pointer. This makes some static analysis easier, by producing fewer false positives. As these are all trivial changes, it seemed best to put them all in a single patch rather than chopping them up per maintainer. Link: http://lkml.kernel.org/r/20170405214711.GA5711@beast Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Jes Sorensen <jes@trained-monkey.org> [runner.c] Cc: Tony Lindgren <tony@atomide.com> Cc: Russell King <linux@armlinux.org.uk> Cc: "Maciej W. Rozycki" <macro@linux-mips.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Daniel Vetter <daniel.vetter@intel.com> Cc: Jani Nikula <jani.nikula@linux.intel.com> Cc: Sean Paul <seanpaul@chromium.org> Cc: David Airlie <airlied@linux.ie> Cc: Yisen Zhuang <yisen.zhuang@huawei.com> Cc: Salil Mehta <salil.mehta@huawei.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Jiri Slaby <jslaby@suse.com> Cc: Patrice Chotard <patrice.chotard@st.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: James Hogan <james.hogan@imgtec.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Matt Redfearn <matt.redfearn@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Mugunthan V N <mugunthanvnm@ti.com> Cc: Felipe Balbi <felipe.balbi@linux.intel.com> Cc: Jarod Wilson <jarod@redhat.com> Cc: Florian Westphal <fw@strlen.de> Cc: Antonio Quartulli <a@unstable.cc> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Kejian Yan <yankejian@huawei.com> Cc: Daode Huang <huangdaode@hisilicon.com> Cc: Qianqian Xie <xieqianqian@huawei.com> Cc: Philippe Reynes <tremyfr@gmail.com> Cc: Colin Ian King <colin.king@canonical.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Christian Gromm <christian.gromm@microchip.com> Cc: Andrey Shvetsov <andrey.shvetsov@k2l.de> Cc: Jason Litzinger <jlitzingerdev@gmail.com> Cc: WANG Cong <xiyou.wangcong@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>