summaryrefslogtreecommitdiff
path: root/drivers/tty
AgeCommit message (Collapse)Author
2015-11-21tty: Fix tty_send_xchar() lock order inversionPeter Hurley
The correct lock order is atomic_write_lock => termios_rwsem, as established by tty_write() => n_tty_write(). Fixes: c274f6ef1c666 ("tty: Hold termios_rwsem for tcflow(TCIxxx)") Reported-and-Tested-by: Dmitry Vyukov <dvyukov@google.com> Cc: <stable@vger.kernel.org> # v3.18+ Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-11-06Merge tag 'asm-generic-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic Pull asm-generic cleanups from Arnd Bergmann: "The asm-generic changes for 4.4 are mostly a series from Christoph Hellwig to clean up various abuses of headers in there. The patch to rename the io-64-nonatomic-*.h headers caused some conflicts with new users, so I added a workaround that we can remove in the next merge window. The only other patch is a warning fix from Marek Vasut" * tag 'asm-generic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: asm-generic: temporarily add back asm-generic/io-64-nonatomic*.h asm-generic: cmpxchg: avoid warnings from macro-ized cmpxchg() implementations gpio-mxc: stop including <asm-generic/bug> n_tracesink: stop including <asm-generic/bug> n_tracerouter: stop including <asm-generic/bug> mlx5: stop including <asm-generic/kmap_types.h> hifn_795x: stop including <asm-generic/kmap_types.h> drbd: stop including <asm-generic/kmap_types.h> move count_zeroes.h out of asm-generic move io-64-nonatomic*.h out of asm-generic
2015-11-05Merge tag 'spi-v4.4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi Pull spi updates from Mark Brown: "Quite a lot of activity in SPI this cycle, almost all of it in drivers with a few minor improvements and tweaks in the core. - Updates to pxa2xx to support Intel Broxton and multiple chip selects. - Support for big endian in the bcm63xx driver. - Multiple slave support for the mt8173 - New driver for the auxiliary SPI controller in bcm2835 SoCs. - Support for Layerscale SoCs in the Freescale DSPI driver" * tag 'spi-v4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi: (87 commits) spi: pxa2xx: Rework self-initiated platform data creation for non-ACPI spi: pxa2xx: Add support for Intel Broxton spi: pxa2xx: Detect number of enabled Intel LPSS SPI chip select signals spi: pxa2xx: Add output control for multiple Intel LPSS chip selects spi: pxa2xx: Use LPSS prefix for defines that are Intel LPSS specific spi: Add DSPI support for layerscape family spi: ti-qspi: improve ->remove() callback spi/spi-xilinx: Fix race condition on last word read spi: Drop owner assignment from spi_drivers spi: Add THIS_MODULE to spi_driver in SPI core spi: Setup the master controller driver before setting the chipselect spi: dw: replace magic constant by DW_SPI_DR spi: mediatek: mt8173 spi multiple devices support spi: mediatek: handle controller_data in mtk_spi_setup spi: mediatek: remove mtk_spi_config spi: mediatek: Update document devicetree bindings to support multiple devices spi: fix kernel-doc warnings about missing return desc in spi.c spi: fix kernel-doc warnings about missing return desc in spi.h spi: pxa2xx: Align a few defines spi: pxa2xx: Save other reg_cs_ctrl bits when configuring chip select ...
2015-11-05Merge tag 'clk-for-linus-20151104' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux Pull clk updates from Stephen Boyd: "The majority of the changes are driver updates and new device support. The core framework is mostly unchanged this time around, with only a couple patches to expose a clk provider API and make getting clk parent names from DT more robust. Driver updates: - Support for clock controllers found on Broadcom Northstar SoCs and bcm2835 SoC - Support for Allwinner audio clocks - A few cleanup patches for Tegra drivers and support for the highest DFLL frequencies on Tegra124 - Samsung exynos7 fixes and improvements - i.Mx SoC updates to add a few missing clocks and keep debug uart clocks on during kernel intialization - Some mediatek cleanups and support for more subsystem clocks - Support for msm8916 gpu/audio clocks and qcom's GDSC power domain controllers - A new driver for the Silabs si514 clock chip" * tag 'clk-for-linus-20151104' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux: (143 commits) clk: qcom: msm8960: Fix dsi1/2 halt bits clk: lpc18xx-cgu: fix potential system hang when disabling unused clocks clk: lpc18xx-ccu: fix potential system hang when disabling unused clocks clk: Add clk_hw_is_enabled() for use by clk providers clk: Add stubs for of_clk_*() APIs when CONFIG_OF=n clk: versatile-icst: fix memory leak clk: Remove clk_{register,unregister}_multiplier() clk: iproc: define Broadcom NS2 iProc clock binding clk: iproc: define Broadcom NSP iProc clock binding clk: ns2: add clock support for Broadcom Northstar 2 SoC clk: iproc: Separate status and control variables clk: iproc: Split off dig_filter clk: iproc: Add PLL base write function clk: nsp: add clock support for Broadcom Northstar Plus SoC clk: iproc: Add PWRCTRL support clk: cygnus: Convert all macros to all caps ARM: cygnus: fix link failures when CONFIG_COMMON_CLK_IPROC is disabled clk: imx31: add missing of_node_put clk: imx27: add missing of_node_put clk: si5351: add missing of_node_put ...
2015-11-05Merge tag 'tty-4.4-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty Pull tty/serial driver updates from Greg KH: "Here is the big tty and serial driver update for 4.4-rc1. Lots of serial driver updates and a few small tty core changes. Full details in the shortlog. All of these have been in linux-next for a while" * tag 'tty-4.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (148 commits) tty: Use unbound workqueue for all input workers tty: Abstract tty buffer work tty: Prevent tty teardown during tty_write_message() tty: core: Use correct spinlock flavor in tiocspgrp() tty: Combine SIGTTOU/SIGTTIN handling serial: amba-pl011: fix incorrect integer size in pl011_fifo_to_tty() ttyFDC: Fix build problems due to use of module_{init,exit} tty: remove unneeded return statement serial: 8250_mid: add support for DMA engine handling from UART MMIO dmaengine: hsu: remove platform data dmaengine: hsu: introduce stubs for the exported functions dmaengine: hsu: make the UART driver in control of selecting this driver serial: fix mctrl helper functions serial: 8250_pci: Intel MID UART support to its own driver serial: fsl_lpuart: add earlycon support tty: disable unbind for old 74xx based serial/mpsc console port serial: pl011: Spelling s/clocks-names/clock-names/ n_tty: Remove reader wakeups for TTY_BREAK/TTY_PARITY chars tty: synclink, fix indentation serial: at91, fix rs485 properties ...
2015-11-05Merge tag 'for-linus-4.4-rc0-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen updates from David Vrabel: - Improve balloon driver memory hotplug placement. - Use unpopulated hotplugged memory for foreign pages (if supported/enabled). - Support 64 KiB guest pages on arm64. - CPU hotplug support on arm/arm64. * tag 'for-linus-4.4-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (44 commits) xen: fix the check of e_pfn in xen_find_pfn_range x86/xen: add reschedule point when mapping foreign GFNs xen/arm: don't try to re-register vcpu_info on cpu_hotplug. xen, cpu_hotplug: call device_offline instead of cpu_down xen/arm: Enable cpu_hotplug.c xenbus: Support multiple grants ring with 64KB xen/grant-table: Add an helper to iterate over a specific number of grants xen/xenbus: Rename *RING_PAGE* to *RING_GRANT* xen/arm: correct comment in enlighten.c xen/gntdev: use types from linux/types.h in userspace headers xen/gntalloc: use types from linux/types.h in userspace headers xen/balloon: Use the correct sizeof when declaring frame_list xen/swiotlb: Add support for 64KB page granularity xen/swiotlb: Pass addresses rather than frame numbers to xen_arch_need_swiotlb arm/xen: Add support for 64KB page granularity xen/privcmd: Add support for Linux 64KB page granularity net/xen-netback: Make it running on 64KB page granularity net/xen-netfront: Make it running on 64KB page granularity block/xen-blkback: Make it running on 64KB page granularity block/xen-blkfront: Make it running on 64KB page granularity ...
2015-11-04Merge branch 'parisc-4.3-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux Pull parisc updates from Helge Deller: "The most important change is that we reduce L1_CACHE_BYTES to 16 bytes, for which a trivial patch for XPS in the network layer was needed. Then we wire up the sys_membarrier and userfaultfd syscalls and added two other small cleanups" * 'parisc-4.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux: parisc: Change L1_CACHE_BYTES to 16 net/xps: Fix calculation of initial number of xps queues parisc: reduce syslog debug output parisc: serial/mux: Convert to uart_console_device instead of open-coded parisc: Wire up userfaultfd syscall parisc: allocate sys_membarrier system call number
2015-11-04Merge remote-tracking branches 'spi/topic/omap-100k', ↵Mark Brown
'spi/topic/omap-uwire', 'spi/topic/owner', 'spi/topic/pxa' and 'spi/topic/pxa2xx' into spi-next
2015-11-01Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
2015-10-28spi: Drop owner assignment from spi_driversAndrew F. Davis
An spi_driver does not need to set an owner, it will be populated by the driver core. Signed-off-by: Andrew F. Davis <afd@ti.com> Acked-by: Jonathan Cameron <jic23@kernel.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-10-23tty/hvc: xen: Use xen page definitionJulien Grall
The console ring is always based on the page granularity of Xen. Signed-off-by: Julien Grall <julien.grall@citrix.com> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-10-22parisc: serial/mux: Convert to uart_console_device instead of open-codedAxel Lin
The implementation of mux_console_device() is very similar to uart_console_device(). Setting .data field in mux_console then we can convert to use uart_console_device(). Signed-off-by: Axel Lin <axel.lin@ingics.com> Signed-off-by: Helge Deller <deller@gmx.de>
2015-10-20Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Conflicts: drivers/net/usb/asix_common.c net/ipv4/inet_connection_sock.c net/switchdev/switchdev.c In the inet_connection_sock.c case the request socket hashing scheme is completely different in net-next. The other two conflicts were overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-18tty: Use unbound workqueue for all input workersPeter Hurley
The commonly accepted wisdom that scheduling work on the same cpu that handled interrupt i/o benefits from cache-locality is only true if the cpu is idle (since bound kworkers are often the highest vruntime and thus the lowest priority). Measurements of scheduling via the unbound queue show lowered worst-case latency responses of up to 5x over bound workqueue, without increase in average latency or throughput. pty i/o test measurements show >3x (!) reduced total running time; tests previously taking ~8s now complete in <2.5s. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-18tty: Abstract tty buffer workPeter Hurley
Introduce API functions to restart and cancel tty buffer work, rather than manipulate buffer work directly. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-18tty: Prevent tty teardown during tty_write_message()Peter Hurley
tty_write_message() allows the caller to directly write to a specific tty. Since the line discipline is bypassed for the direct write, nothing prevents the tty from being torn down after the tty count is checked. Hold the tty lock for the duration of the direct write. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-18tty: core: Use correct spinlock flavor in tiocspgrp()Peter Hurley
tiocspgrp() is the ioctl handler for TIOCSPGRP, which runs in non-atomic context; use spin_lock/unlock_irq (since interrupt state is on). Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-18tty: Combine SIGTTOU/SIGTTIN handlingPeter Hurley
The job_control() check in n_tty_read() has nearly identical purpose and results as tty_check_change(). Both functions' purpose is to determine if the current task's pgrp is the foreground pgrp for the tty, and if not, to signal the current pgrp. Introduce __tty_check_change() which takes the signal to send and performs the shared operations for job control() and tty_check_change(). Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-18serial: amba-pl011: fix incorrect integer size in pl011_fifo_to_tty()Timur Tabi
The UART_DUMMY_DR_RX status bit is equal to (1 << 16), so a u16 is too small to hold that value. The result is that UART_DUMMY_DR_RX is never passed to uart_insert_char(). This means that we're always accepting characters, even when CREAD (in termios) is not set. Signed-off-by: Timur Tabi <timur@codeaurora.org> Reviewed-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-18ttyFDC: Fix build problems due to use of module_{init,exit}James Hogan
Commit 0fd972a7d91d (module: relocate module_init from init.h to module.h) broke the build of ttyFDC driver due to that driver's (mis)use of module_mips_cdmm_driver() without first including module.h, for example: In file included from ./arch/mips/include/asm/cdmm.h +11 :0, from drivers/tty/mips_ejtag_fdc.c +34 : include/linux/device.h +1295 :1: warning: data definition has no type or storage class ./arch/mips/include/asm/cdmm.h +84 :2: note: in expansion of macro ‘module_driver’ drivers/tty/mips_ejtag_fdc.c +1157 :1: note: in expansion of macro ‘module_mips_cdmm_driver’ include/linux/device.h +1295 :1: error: type defaults to ‘int’ in declaration of ‘module_init’ [-Werror=implicit-int] ./arch/mips/include/asm/cdmm.h +84 :2: note: in expansion of macro ‘module_driver’ drivers/tty/mips_ejtag_fdc.c +1157 :1: note: in expansion of macro ‘module_mips_cdmm_driver’ drivers/tty/mips_ejtag_fdc.c +1157 :1: warning: parameter names (without types) in function declaration Instead of just adding the module.h include, switch to using the new builtin_mips_cdmm_driver() helper macro and drop the remove callback, since it isn't needed. If module support is added later, the code can always be resurrected. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jslaby@suse.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: linux-mips@linux-mips.org Cc: <stable@vger.kernel.org> # 4.2.x- Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-18tty: remove unneeded return statementGuillaume Gomez
Signed-off-by: Guillaume Gomez <guillaume1.gomez@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-18Revert "serial: 8250_dma: don't bother DMA with small transfers"Frederic Danis
This reverts commit 9119fba0cfeda6d415c9f068df66838a104b87cb. This commit prevents from sending "big" file using Bluetooth. When sending a lot of data quickly through the Bluetooth interface, and after a variable amount of data sent, transfer fails with error: kernel: [ 415.247453] Bluetooth: hci0 hardware error 0x00 Found on T100TA. After reverting this commit, send works fine for any file size. Signed-off-by: Frederic Danis <frederic.danis@linux.intel.com> Fixes: 9119fba0cfed (serial: 8250_dma: don't bother DMA with small transfers) Cc: stable@vger.kernel.org Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-18serial: 8250_mid: add support for DMA engine handling from UART MMIOHeikki Krogerus
The platforms that have this UART, but that don't have separate PCI device for the DMA Engine, need to create the HSU DMA Engine device separately. Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-18dmaengine: hsu: make the UART driver in control of selecting this driverHeikki Krogerus
HSU (High Speed UART) DMA engine, like the name suggests, is an integrated DMA engine for UART and UART alone. Therefore, making the UART drivers responsible of selecting it and removing the user selectable option for it. The UARTs with this DMA engine can always select HSU_DMA when SERIAL_8250_DMA option is enabled. Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Acked-by: Vinod Koul <vinod.koul@intel.com> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-18serial: fix mctrl helper functionsArnd Bergmann
A recent patch to create common helper functions for modem control lines created empty helper functions in a header file, but accidentally did not mark them as 'static inline', which causes build errors: drivers/tty/serial/mxs-auart.o: In function `mctrl_gpio_enable_ms': mxs-auart.c:(.text+0x171c): multiple definition of `mctrl_gpio_enable_ms' drivers/tty/serial/clps711x.o:clps711x.c:(.text+0x768): first defined here drivers/tty/serial/mxs-auart.o: In function `mctrl_gpio_disable_ms': mxs-auart.c:(.text+0x1720): multiple definition of `mctrl_gpio_disable_ms' drivers/tty/serial/clps711x.o:clps711x.c:(.text+0x76c): first defined here This adds the missing annotation, so the functions do not get placed in each object file. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Fixes: ce59e48fdbad ("serial: mctrl_gpio: implement interrupt handling") Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-18serial: 8250_pci: Intel MID UART support to its own driverHeikki Krogerus
Intel MID UART quirks require already quite a bit of code in 8250_pci.c. On new Intel platforms where it is used, the integrated DMA engine no longer has its own PCI device, but is instead configured from the UART's MMIO. That means we will have to add even more code for handling just MID UARTs. Instead of adding that to 8250_pci.c, splitting the support of Intel MID UART into its own driver. Handling of the integrated DMA engine becomes much simpler this way. Own driver will also remove the need for things like specific set_termios hooks for every board using this UART, and simplify the handling of it in general. Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-18serial: fsl_lpuart: add earlycon supportStefan Agner
Add support for DT and command line based earlycon support for lpuart and lpuart32 used on Freescale Vybrid and and QorIQ LS1021A processors. Signed-off-by: Stefan Agner <stefan@agner.ch> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-18tty: disable unbind for old 74xx based serial/mpsc console portPaul Gortmaker
We recently got rid of some modular code in this driver and also got rid of the unused ".remove" function at the same time. Thierry noted that it was however possible to force the remove through the bind/unbind interface. Since this is a console device used on 2005 vintage 74xx based powerpc embedded targets, and is essentially always used in conjunction with SERIAL_MPSC_CONSOLE=y -- there is no sane reason anyone would ever want to unbind the builtin driver and lose the console. So we just explicitly block bind/unbind operations and prevent root from shooting themselves in the foot. Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jslaby@suse.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: linux-serial@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-18n_tty: Remove reader wakeups for TTY_BREAK/TTY_PARITY charsPeter Hurley
Waking the reader immediately upon receipt of TTY_BREAK or TTY_PARITY chars has no effect on the outcome of read(): 1. Only non-canonical/EXTPROC mode applies since canonical mode will not return data until a line termination is received anyway 2. EXTPROC mode - the reader will always be woken by the input worker 3. Non-canonical modes a. MIN == 0, TIME == 0 b. MIN == 0, TIME > 0 c. MIN > 0, TIME > 0 minimum_to_wake is always 1 in these modes so the reader will always be woken by the input worker d. MIN > 0, TIME == 0 although the reader will not be woken by the input worker unless the minimum data is received, the reader would not otherwise have returned the received data Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-18tty: synclink, fix indentationJiri Slaby
The statement after if should be indenteted. So fix this. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-18serial: at91, fix rs485 propertiesJiri Slaby
There is a misplaced bracket in atmel_init_rs485 which sets rs485-rx-during-tx and rs485-enabled-at-boot-time only if rs485-rts-delay is set in of. This is clearly a bug, so fix it by moving the bracket to the proper place. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Elen Song <elen.song@atmel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-18tty: r3964: Replace/remove bogus tty lock usePeter Hurley
The tty lock is strictly for serializing tty lifetime events (open/close/hangup), and not for line discipline serialization. The tty core already provides serialization of concurrent writes to the same tty, and line discipline lifetime management (by ldisc references), so pinning the tty via tty_lock() is unnecessary and counter-productive; remove tty lock use. However, the line discipline is responsible for serializing reads (if required by the line discipline); add read_lock mutex to serialize calls of r3964_read(). Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-18tty: r3964: Use tty->read_wait waitqueuePeter Hurley
The tty core provides read_wait waitqueue specifically for line disciplines to wait readers; otherwise, the line discipline may miss wakeups generated by the tty core. NB: The tty core already provides serialization for the line discipline's close() method, and guarantees no readers or writers will be using the closing instance of the line discipline. Completely remove that wakeup. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-18tty: Remove tty_port::close_waitPeter Hurley
With the removal of tty_wait_until_sent_from_close(), tty drivers no longer wait during open for parallel closes to complete (instead, the tty core waits before calling the driver open() method). Thus, the close_wait waitqueue is no longer used for waiting. Remove struct tty_port::close_wait. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-18tty: Remove ASYNC_CLOSING checks in open()/hangup() methodsPeter Hurley
Since at least before 2.6.30, tty drivers that do not drop the tty lock while closing cannot observe ASYNC_CLOSING set while holding the tty lock; this includes the tty driver's open() and hangup() methods, since the tty core calls these methods holding the tty lock. For these drivers, waiting for ASYNC_CLOSING to clear while opening is not required, since this condition cannot occur. Similarly, even when the open() method drops and reacquires the tty lock after blocking, ASYNC_CLOSING cannot be set (again, for drivers that do not drop the tty lock while closing). Now that tty port drivers no longer drop the tty lock while closing (since 'tty: Remove tty_wait_until_sent_from_close()'), the same conditions apply: waiting for ASYNC_CLOSING to clear while opening is not required, nor is re-checking ASYNC_CLOSING after dropping and reacquiring the tty lock while blocking (eg., in *_block_til_ready()). Note: The ASYNC_CLOSING flag state is still maintained since several bitrotting drivers use it for (dubious) other purposes. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-18tty: Remove tty_wait_until_sent_from_close()Peter Hurley
tty_wait_until_sent_from_close() drops the tty lock while waiting for the tty driver to finish sending previously accepted data (ie., data remaining in its write buffer and transmit fifo). tty_wait_until_sent_from_close() was added by commit a57a7bf3fc7e ("TTY: define tty_wait_until_sent_from_close") to prevent the entire tty subsystem from being unable to open new ttys while waiting for one tty to close while output drained. However, since commit 0911261d4cb6 ("tty: Don't take tty_mutex for tty count changes"), holding a tty lock while closing does not prevent other ttys from being opened/closed/hung up, but only prevents lifetime event changes for the tty under lock. Holding the tty lock while waiting for output to drain does prevent parallel non-blocking opens (O_NONBLOCK) from advancing or returning while the tty lock is held. However, all parallel opens _already_ block even if the tty lock is dropped while closing and the parallel open advances. Blocking in open has been in mainline since at least 2.6.29 (see tty_port_block_til_ready(); note the test for O_NONBLOCK is _after_ the wait while ASYNC_CLOSING). IOW, before this patch a non-blocking open will sleep anyway for the _entire_ duration of a parallel hardware shutdown, and when it wakes, the error return will cause a release of its tty, and it will restart with a fresh attempt to open. Similarly with a blocking open that is already waiting; when it's woken, the hardware shutdown has already completed to ASYNC_INITIALIZED is not set, which forces a release and restart as well. So, holding the tty lock across the _entire_ close (which is what this patch does), even while waiting for output to drain, is equivalent to the current outcome wrt parallel opens. Cc: Alan Cox <alan@linux.intel.com> Cc: David Laight <David.Laight@aculab.com> CC: Arnd Bergmann <arnd@arndb.de> CC: Karsten Keil <isdn@linux-pingi.de> CC: linuxppc-dev@lists.ozlabs.org Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-18serial: tegra: Add helper function for handling RX bufferJon Hunter
In the tegra UART driver there are three places where the RX DMA buffer is handled and pushed up to the tty layer. In all three instances the same functions are called and so instead of duplicating the code in three places, move this code to a new helper function and use this new function. Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-18serial: tegra: Remove redundant code and check in tegra_uart_stop_rx()Jon Hunter
The serial-tegra driver always uses DMA and hence the driver always allocates DMA channels. Therefore, the test to see if the RX DMA channel is initialised in tegra_uart_stop_rx() is unnecessary and so remove the test and the code that corresponds to the case where the RX DMA channel is not initialised. Please note that the call to tegra_uart_stop_rx() should always be before the call to tegra_uart_shutdown() which will uninitialise the RX DMA channel. Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-18serial: tegra: Remove unnecessary return statementsJon Hunter
Some functions in the serial-tegra driver have unnecessary return statements at the end of a void function and so remove them. Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-18serial: tegra: Handle another RX race conditionJon Hunter
Commit 853a699739fe ("serial: tegra: handle race condition on uart rx side") attempted to fix a race condition between the RX end of transmission interrupt and RX DMA completion callback. Despite this fix there is still another case where these two paths can race and result in duplicated data. The race condition is as follows: 1. DMA completion interrupt occurs and schedules tasklet to call DMA callback. 2. DMA callback for the UART driver starts to execute. This will copy the data from the DMA buffer and restart the DMA. This is done under uart port spinlock. 3. During the callback, UART interrupt is raised for end of receive. The UART ISR runs and waits to acquire port spinlock held by the DMA callback. 4. DMA callback gives up spinlock after copying the data, but before restarting DMA. 5. UART ISR acquires the spin lock and reads the same DMA buffer because DMA has not been restarted yet. The release of the spinlock during the DMA callback was introduced by commit 9b88748b362c ("tty: serial: tegra: drop uart_port->lock before calling tty_flip_buffer_push()") to fix a spinlock lock-up issue when calling tty_flip_buffer_push(). However, since then commit a9c3f68f3cd8 ("tty: Fix low_latency BUG") migrated tty_flip_buffer_push() to always use a workqueue, allowing tty_flip_buffer_push() to be called from within atomic sections. Therefore, we can remove the unlocking of the spinlock from the DMA callback and UART ISR and this will ensure that the race condition no longer occurs. Reported-by: Christopher Freeman <cfreeman@nvidia.com> Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-18serial: 8250_omap: Remove RTS clearPeter Hurley
Clearing UART_MCR_RTS or UART_MCR_XONANY is unnecessary; these bits are never set in the shadow mcr. The RTS clear is especially confusing. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-18serial: Enable Freescale 16550 workaround on armScott Wood
The same serial hardware is present on LS2080A which is arm64, and LS1021A which is arm32, so don't limit the workaround to PPC. Unlike PPC which uses arch/powerpc/kernel/legacy_serial.c, the ARM targets use drivers/tty/serial/of_serial.c, so add the handle_irq override check there as well. Signed-off-by: Scott Wood <scottwood@freescale.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-18tty: serial: men_z135_uart.c: use mcb memory region size instead of ↵Andreas Werner
hardcoded one There is no need to hardcode the MEN_Z135_MEM_SIZE. The MCB subsystem already knowns the size which is located in the chameleon table. MCB parse the chameleon table to get the resources of each IP and provide the mcb_request_mem function to get those resources. Use mcb_request_mem to get the resources. This function also takes care of the memory region naming allocated by the driver for each of the instances. Signed-off-by: Andreas Werner <andy@wernerandy.de> Acked-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-18serial: atmel: fix compiler warning on address castAndre Przywara
Turning on KVM and LPAE support on top of a multi_v7_defconfig will produce a compiler warning in the Atmel serial driver: drivers/tty/serial/atmel_serial.c: In function 'atmel_verify_port': drivers/tty/serial/atmel_serial.c:2299:6: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast] if ((void *)port->mapbase != ser->iomem_base) ^ Fix that by using the cast on the right hand side instead, as similar code already does in other drivers. Signed-off-by: Andre Przywara <andre.przywara@arm.com> Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-14n_tracesink: stop including <asm-generic/bug>Christoph Hellwig
<asm-generic/bug> contains the default implementation of BUG() and friends, which architectures may decide to use. The proper way to get them is <linux/bug.h>, so use that. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2015-10-14n_tracerouter: stop including <asm-generic/bug>Christoph Hellwig
<asm-generic/bug> contains the default implementation of BUG() and friends, which architectures may decide to use. The proper way to get them is <linux/bug.h>, so use that. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2015-10-12Merge 4.3-rc5 into tty-nextGreg Kroah-Hartman
We want the tty fixes and reverts in here as well so that people can properly test and use it. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04drivers/tty: require read access for controlling terminalJann Horn
This is mostly a hardening fix, given that write-only access to other users' ttys is usually only given through setgid tty executables. Signed-off-by: Jann Horn <jann@thejh.net> Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04serial: 8250: add uart_config entry for PORT_RT2880Mans Rullgard
This adds an entry to the uart_config table for PORT_RT2880 enabling rx/tx FIFOs. The UART is actually a Palmchip BK-3103 which is found in several devices from Alchemy/RMI, Ralink, and Sigma Designs. Signed-off-by: Mans Rullgard <mans@mansr.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04tty: serial: msm: Remove 115.2 Kbps maximum baud rate limitationIvan T. Ivanov
UART controller is capable to perform transfers up to 4 Mbps. Remove artificial 115.2 Kbps limitation. Signed-off-by: Ivan T. Ivanov <ivan.ivanov@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>