summaryrefslogtreecommitdiffstats
Commit message (Collapse)AuthorAgeFilesLines
* Merge tag 'tty-4.4-rc1' of ↵Linus Torvalds2015-11-0482-1807/+2600
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 ...
| * tty: Use unbound workqueue for all input workersPeter Hurley2015-10-171-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * tty: Abstract tty buffer workPeter Hurley2015-10-175-3/+15
| | | | | | | | | | | | | | | | 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>
| * tty: Prevent tty teardown during tty_write_message()Peter Hurley2015-10-171-4/+2
| | | | | | | | | | | | | | | | | | | | | | | | 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>
| * tty: core: Use correct spinlock flavor in tiocspgrp()Peter Hurley2015-10-171-3/+2
| | | | | | | | | | | | | | | | | | 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>
| * tty: Combine SIGTTOU/SIGTTIN handlingPeter Hurley2015-10-173-46/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * serial: amba-pl011: fix incorrect integer size in pl011_fifo_to_tty()Timur Tabi2015-10-171-2/+2
| | | | | | | | | | | | | | | | | | | | | | 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>
| * ttyFDC: Fix build problems due to use of module_{init,exit}James Hogan2015-10-171-34/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * tty: remove unneeded return statementGuillaume Gomez2015-10-171-1/+1
| | | | | | | | | | Signed-off-by: Guillaume Gomez <guillaume1.gomez@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * serial: 8250_mid: add support for DMA engine handling from UART MMIOHeikki Krogerus2015-10-172-2/+71
| | | | | | | | | | | | | | | | | | | | 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>
| * dmaengine: hsu: remove platform dataHeikki Krogerus2015-10-175-23/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | There are no platforms where it's not possible to calculate the number of channels based on IO space length, and since that is the only purpose for struct hsu_dma_platform_data, removing it. 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>
| * dmaengine: hsu: introduce stubs for the exported functionsHeikki Krogerus2015-10-171-0/+10
| | | | | | | | | | | | | | | | | | | | This allows UART drivers to register HSU DMA Engine without being forced to use ifdefs. 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>
| * dmaengine: hsu: make the UART driver in control of selecting this driverHeikki Krogerus2015-10-172-7/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * serial: fix mctrl helper functionsArnd Bergmann2015-10-171-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * serial: 8250_pci: Intel MID UART support to its own driverHeikki Krogerus2015-10-174-222/+273
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * serial: fsl_lpuart: add earlycon supportStefan Agner2015-10-173-0/+47
| | | | | | | | | | | | | | | | | | 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>
| * tty: disable unbind for old 74xx based serial/mpsc console portPaul Gortmaker2015-10-171-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * serial: pl011: Spelling s/clocks-names/clock-names/Geert Uytterhoeven2015-10-171-1/+1
| | | | | | | | | | Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * n_tty: Remove reader wakeups for TTY_BREAK/TTY_PARITY charsPeter Hurley2015-10-171-4/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * tty: synclink, fix indentationJiri Slaby2015-10-171-1/+1
| | | | | | | | | | | | | | 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>
| * serial: at91, fix rs485 propertiesJiri Slaby2015-10-171-3/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * tty: Remove wait_event_interruptible_tty()Peter Hurley2015-10-171-26/+0
| | | | | | | | | | | | | | | | In-tree users of wait_event_interruptible_tty() have been removed; remove. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * tty: r3964: Replace/remove bogus tty lock usePeter Hurley2015-10-172-9/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * tty: r3964: Use tty->read_wait waitqueuePeter Hurley2015-10-172-9/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * tty: Remove tty_port::close_waitPeter Hurley2015-10-176-7/+0
| | | | | | | | | | | | | | | | | | | | | | | | 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>
| * usb: gadget: gserial: Privatize close_waitPeter Hurley2015-10-171-2/+4
| | | | | | | | | | | | | | | | close_wait is no longer needed or provided by the tty core. Move close_wait to struct gs_port. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * tty: Remove ASYNC_CLOSING checks in open()/hangup() methodsPeter Hurley2015-10-179-142/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * tty: Remove tty_wait_until_sent_from_close()Peter Hurley2015-10-175-30/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * serial: tegra: Add helper function for handling RX bufferJon Hunter2015-10-171-42/+24
| | | | | | | | | | | | | | | | | | | | 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>
| * serial: tegra: Remove redundant code and check in tegra_uart_stop_rx()Jon Hunter2015-10-171-10/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * serial: tegra: Remove unnecessary return statementsJon Hunter2015-10-171-11/+0
| | | | | | | | | | | | | | | | 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>
| * serial: tegra: Handle another RX race conditionJon Hunter2015-10-171-8/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * serial: 8250_omap: Remove RTS clearPeter Hurley2015-10-171-1/+0
| | | | | | | | | | | | | | | | 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>
| * serial: Enable Freescale 16550 workaround on armScott Wood2015-10-172-2/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * tty: serial: men_z135_uart.c: use mcb memory region size instead of ↵Andreas Werner2015-10-171-8/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * serial: atmel: fix compiler warning on address castAndre Przywara2015-10-171-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * Merge 4.3-rc5 into tty-nextGreg Kroah-Hartman2015-10-12421-2011/+3234
| |\ | | | | | | | | | | | | | | | | | | 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>
| * | Documentation: improve line discipline method descriptionsTilman Schmidt2015-10-051-21/+39
| | | | | | | | | | | | | | | | | | | | | | | | | | | Mention that the ldisc open method must set tty->receive_room, and that many methods are optional. Add description of receive_buf2 method. Signed-off-by: Tilman Schmidt <tilman@imap.cc> Reviewed-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | tty: serial: msm: Remove 115.2 Kbps maximum baud rate limitationIvan T. Ivanov2015-10-041-3/+17
| | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | tty: serial: msm: Add RX DMA supportIvan T. Ivanov2015-10-043-3/+236
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add receive DMA support for UARTDM type of controllers. Tested on APQ8064, which have UARTDM v1.3 and ADM DMA engine and APQ8016, which have UARTDM v1.4 and BAM DMA engine. Signed-off-by: Ivan T. Ivanov <ivan.ivanov@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | tty: serial: msm: Add TX DMA supportIvan T. Ivanov2015-10-043-24/+294
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add transmit DMA support for UARTDM type of controllers. Tested on APQ8064, which have UARTDM v1.3 and ADM DMA engine and APQ8016, which have UARTDM v1.4 and BAM DMA engine. Signed-off-by: Ivan T. Ivanov <ivan.ivanov@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | tty: serial: msm: Add msm prefix to all driver functionsIvan T. Ivanov2015-10-041-21/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | Make function naming consistent across this driver. Also rename msm_irq to msm_uart_irq. No functional changes. Signed-off-by: Ivan T. Ivanov <ivan.ivanov@linaro.org> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | tty: serial: msm: replaces (1 << x) with BIT(x) macroPramod Gurav2015-10-041-22/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | Replaces (1 << x) with BIT(x) macro Signed-off-by: Pramod Gurav <gpramod@codeaurora.org> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Ivan T. Ivanov <ivan.ivanov@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | tty: serial: msm: Add mask value for UART_DM registersPramod Gurav2015-10-042-6/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The bit masks for RFR_LEVEL1 and STALE_TIMEOUT_MSB values in MR1 and IPR registers respectively are different for UART and UART_DM hardware cores. We have been using UART core mask values for these. Add the same for UART_DM core. There is no bit setting as UART_IPR_RXSTALE_LAST for UART_DM core so do it only for UART core. Signed-off-by: Pramod Gurav <gpramod@codeaurora.org> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Ivan T. Ivanov <ivan.ivanov@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | sc16is7xx: null ptr checkSean Nyekjaer2015-10-041-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | If a wrong compatible flag in specified, the of_match_device returning null. Implemented check and if NULL then returning -ENODEV. Signed-off-by: Sean Nyekjaer <sean.nyekjaer@prevas.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | serial: omap: remove warnings about unused functionsEzequiel Garcia2015-10-041-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | They're used by only if CONFIG_PM is enabled, so enclose them with proper ifdefs. Removes these warnings: drivers/tty/serial/omap-serial.c:202:12: warning: 'serial_omap_get_context_loss_count' defined but not used [-Wunused-function] drivers/tty/serial/omap-serial.c:213:13: warning: 'serial_omap_enable_wakeup' defined but not used [-Wunused-function] Signed-off-by: Guido Martínez <guido@vanguardiasur.com.ar> Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | mpsc: use dma_set_mask insted of dma_supportedChristoph Hellwig2015-10-041-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | This ensures the dma mask that is supported by the driver is recorded in the device structure. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | serial: 8250_dma: no need to sync RX bufferAndy Shevchenko2015-10-041-6/+0
| | | | | | | | | | | | | | | | | | | | | | | | RX buffer is allocated from DMA coherent memory. Thus there is no need to call DMA sync API for it. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | serial: 8250: Refactor serial console restore-from-suspendPeter Hurley2015-10-041-14/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Move h/w reinit of serial console restore-from-suspend into standalone helper function. No functional change. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | serial: 8250: Tolerate clock variance for max baud rateJames Hogan2015-10-041-9/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When the UART clock is set slightly under 1.8432MHz, the 8250 driver core doesn't permit the 115200 baud rate since it calculates the maximum frequency to pass to uart_get_baud_rate by simply dividing the uart clock by 16 which yields a value slightly under 115200, even though the frequency is close enough for the UART to operate reliably. Therefore add some tolerance in the calculation of the maximum baud rate. 1% tolerance allows for marginally slower uart clk than nominal without introducing transmission errors. Signed-off-by: James Hogan <james.hogan@imgtec.com> [pjh: Forward-port & refactor original patch; change tolerance to 1%] Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
OpenPOWER on IntegriCloud