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path: root/drivers/tty/serial
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2015-02-03serial: of-serial: fetch line number from DTLucas Stach
The general agreed way to specify a fixed line number for a serial console is to provide a "serial" alias in the devicetree. Start parsing this property in of_serial. Signed-off-by: Lucas Stach <dev@lynxeye.de> Acked-by: Olof Johansson <olof@lixom.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02serial: samsung: earlycon support depends on CONFIG_SERIAL_SAMSUNG_CONSOLEMarek Szyprowski
EarlyCon support depends on serial console infrastructure, so the code implementing it should depend on CONFIG_SERIAL_SAMSUNG_CONSOLE. This patch fixes the following build break: CC [M] drivers/tty/serial/samsung.o drivers/tty/serial/samsung.c:2468:1: error: expected declaration specifiers or ‘...’ before string constant drivers/tty/serial/samsung.c:2468:1: error: expected declaration specifiers or ‘...’ before ‘s3c2410_setup_earlycon’ drivers/tty/serial/samsung.c:2487:1: error: expected declaration specifiers or ‘...’ before string constant drivers/tty/serial/samsung.c:2487:1: error: expected declaration specifiers or ‘...’ before ‘s3c2412_setup_earlycon’ drivers/tty/serial/samsung.c:2488:1: error: expected declaration specifiers or ‘...’ before string constant drivers/tty/serial/samsung.c:2488:1: error: expected declaration specifiers or ‘...’ before ‘s3c2440_setup_earlycon’ drivers/tty/serial/samsung.c:2489:1: error: expected declaration specifiers or ‘...’ before string constant drivers/tty/serial/samsung.c:2489:1: error: expected declaration specifiers or ‘...’ before ‘s3c6400_setup_earlycon’ drivers/tty/serial/samsung.c:2506:1: error: expected declaration specifiers or ‘...’ before string constant drivers/tty/serial/samsung.c:2506:1: error: expected declaration specifiers or ‘...’ before ‘s5pv210_setup_earlycon’ drivers/tty/serial/samsung.c:2507:1: error: expected declaration specifiers or ‘...’ before string constant drivers/tty/serial/samsung.c:2507:1: error: expected declaration specifiers or ‘...’ before ‘exynos4210_setup_earlycon’ drivers/tty/serial/samsung.c:2468:1: warning: ‘s3c2410_setup_earlycon’ defined but not used [-Wunused-function] drivers/tty/serial/samsung.c:2487:1: warning: ‘s3c2412_setup_earlycon’ defined but not used [-Wunused-function] drivers/tty/serial/samsung.c:2488:1: warning: ‘s3c2440_setup_earlycon’ defined but not used [-Wunused-function] drivers/tty/serial/samsung.c:2489:1: warning: ‘s3c6400_setup_earlycon’ defined but not used [-Wunused-function] drivers/tty/serial/samsung.c:2506:1: warning: ‘s5pv210_setup_earlycon’ defined but not used [-Wunused-function] drivers/tty/serial/samsung.c:2507:1: warning: ‘exynos4210_setup_earlycon’ defined but not used [-Wunused-function] make[3]: *** [drivers/tty/serial/samsung.o] Error 1 Reported-by: kbuild test robot <fengguang.wu@intel.com> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02tty/serial: serial8250_set_divisor() can be statickbuild test robot
drivers/tty/serial/8250/8250_core.c:2503:6: sparse: symbol 'serial8250_set_divisor' was not declared. Should it be static? Signed-off-by: Fengguang Wu <fengguang.wu@intel.com> Cc: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02tty/serial: Add Spreadtrum sc9836-uart driver supportChunyan Zhang
Add a full sc9836-uart driver for SC9836 SoC which is based on the spreadtrum sharkl64 platform. This driver also support earlycon. Originally-by: Lanqing Liu <lanqing.liu@spreadtrum.com> Signed-off-by: Orson Zhai <orson.zhai@spreadtrum.com> Signed-off-by: Chunyan Zhang <chunyan.zhang@spreadtrum.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02serial: samsung: remove redundant interrupt enablingRobert Baldyga
Function s3c24xx_serial_start_tx_pio() enables interrupts if needed, so we don't have to (or even we shouldn't) enable them before. Signed-off-by: Robert Baldyga <r.baldyga@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02serial: omap: Fix RTS handlingPeter Hurley
The OMAP UART ignores MCR[1] (ie., RTS) when in autoRTS mode. This makes it impossible for either the serial core or userspace to manually flow control the sender. Disable autoRTS mode when RTS is lowered and restore the previous mode when RTS is raised. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02serial: 8250_omap: Use UPSTAT_AUTORTS for RTS handlingPeter Hurley
Commit 88838d3112702 ("serial: omap_8250: Fix RTS handling") fixed RTS pin control when in autoRTS mode. New support added in "serial: core: Rework hw-assisted flow control support" enables a much simpler approach; rather than masking out autoRTS whenever writing the EFR register, use the UPSTAT_* mode to determine if autoRTS should be enabled when raising RTS (in omap8250_set_mctrl()). Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02serial: core: Rework hw-assisted flow control supportPeter Hurley
hw-assisted flow control support was added to the serial core in v3.8 with commits, dba05832cbe4f ("SERIAL: core: add hardware assisted h/w flow control support") 2cbacafd7af0f ("SERIAL: core: add hardware assisted s/w flow control support") 9aba8d5b01119 ("SERIAL: core: add throttle/unthrottle callbacks for hardware assisted flow control") Since then, additional requirements for serial core support have arisen. Specifically, 1. Separate tx and rx flow control settings for UARTs which only support tx flow control (ie., autoCTS). 2. Disable sw-assisted CTS flow control in autoCTS mode 3. Support for RTS flow control by serial core and userspace in autoRTS mode Distinguish mode from capability; introduce UPSTAT_AUTORTS, UPSTAT_AUTOCTS and UPSTAT_AUTOXOFF which, when set by the uart driver, enable serial core support for hw-assisted rx, hw-assisted tx and hw-assisted in-band/IXOFF rx flow control, respectively. [Note: hw-assisted in-band/IXON tx flow control does not require serial core support/intervention and can be enabled by the uart driver when required.] These modes must be set/reset in the driver's set_termios() method, based on termios settings, and thus can be safely queried in any context in which one of the port lock, port mutex or termios rwsem are held. Set these modes in the 2 in-tree drivers, omap-serial and 8250_omap, which currently use UPF_HARD_FLOW/UPF_SOFT_FLOW support. Retain UPF_HARD_FLOW and UPF_SOFT_FLOW as capabilities; re-define UPF_HARD_FLOW as both UPF_AUTO_RTS and UPF_AUTO_CTS to allow for distinct and separate rx and tx flow control capabilities. Disable sw-assisted CTS flow control when UPSTAT_AUTOCTS is enabled. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02tty/serial: 8250_early: Add support for PXA UARTsRob Herring
The PXA variant of the 8250 UART adds a UART enable bit which must not be cleared. Make the earlycon support maintain this bit if it is set. This implies some initialization of the UART, but we cannot unconditionally set the bit as some other variants require this bit to be clear for other functions. Signed-off-by: Rob Herring <robh@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jslaby@suse.cz> Cc: linux-serial@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02tty/serial: of_serial: add support for PXA/MMP uartsRob Herring
Add mrvl,pxa-uart and mrvl,mmp-uart compatible strings for the of_serial driver. These are 8250 variants which have a port type of PORT_XSCALE. There is also the serial driver pxa.c with these compatible strings already. However, it can be replaced with the common 8250 driver. It has some issues like it cannot coexist with the 8250 driver due to tty name collision. That also means adding these compatible strings here should not case a problem. Signed-off-by: Rob Herring <robh@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jslaby@suse.cz> Cc: linux-serial@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02tty/serial: of_serial: add DT alias ID handlingRob Herring
Add support for alias parsing from the DT. This allows for consistent tty numbering. Signed-off-by: Rob Herring <robh@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jslaby@suse.cz> Cc: linux-serial@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02serial: 8250: Prevent concurrent updates to shadow registersPeter Hurley
The port shadow registers, ->fcr and ->mcr, must be protected from concurrent updates. Relocate the shadow register updates in serial8250_do_set_termios() to the port lock critical section. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02serial: 8250: Use canary to restart console after suspendPeter Hurley
When using no_console_suspend, the serial console may be powered off anyway during system sleep. Upon resume, the port may be in its default power-on state, but is expected to continue console i/o before the device has received its pm callback. The resultant garbage i/o can cause all kinds of havoc on the remote end. Use the scratch register as a canary to discover if the console has been powered-off. Write a non-zero value to the scratch register at port suspend and reprogram the port before any console i/o if the scratch register != canary before port resume. This workaround is disabled for omap_8250 (which uses different divisor programming). Credit to Doug Anderson <dianders@chromium.org> for the idea of using the scratch register canary to discover port power-down. Cc: Doug Anderson <dianders@chromium.org> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02serial: 8250: Refactor XR17V35X divisor calculationPeter Hurley
Exar XR17V35X PCIe uarts support a 4-bit fractional divisor register. Refactor the divisor calculation from the divisor programming. Allow a fractional result from serial8250_get_divisor() and pass this result to serial8250_dl_write(). Simplify the calculation for quot and quot_frac. This was verified to be identical to the results of the original calculation with a test jig. NB: The results were also compared with the divisor value chart on pg 33 of the Exar XR17V352 datasheet, rev 1.0.3, here: http://www.exar.com/common/content/document.ashx?id=1585 which differs from the calculated values by 1 in the fractional result. This is because the calculated values are still rounded in the fractional result, whereas the table values are truncated. Note that the data error rate % values in the datasheet are for rounded fractional results, as the truncated fractional results have more error. Cc: Joe Schultz <jschultz@xes-inc.com> Cc: Aaron Sierra <asierra@xes-inc.com> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02serial: 8250: Refactor divisor programmingPeter Hurley
Refactor divisor register programming into a new function, serial8250_set_divisor; this allows serial console to reinitialize early after resume from suspend. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02serial: 8250: Refactor LCR computationPeter Hurley
Refactor the computation of the LCR register value from termios c_cflag into a new local function, serial8250_compute_lcr(). Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02serial: 8250: Move UART_BUG_QUOT workaroundPeter Hurley
The UART_BUG_QUOT workaround adjusts the divisor computed from the baud rate by serial8250_get_divisor(). Move the workaround into serial8250_get_divisor(), so that divisor-from-baud computation is encapsulated. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02tty: serial: men_z135_uart: Fix driver for changes in hardwareJohannes Thumshirn
16z135 IP Core has changed so the driver needs to be updated to respect these changes. The following changes have been made: * Don't invert the 16z135 modem status register when reading. * Add module parameter to configure the (baud rate dependent) RX timeout. Character timeout in seconds = (timeout_reg * baud_reg * 4)/freq_reg. * Enable the handling of UART core's automatic flow control feature. When AFE is active disable generation of modem status IRQs. * Rework the handling of IRQs to be conform with newer FPGA versions and take precautions not to miss an interrupt because of the destructive read of the IIR register. * Correct men_z135_handle_modem_status(), MSR is stat_reg[15:8] not stat_reg[7:0] * Correct calling of uart_handle_{dcd,cts}_change() * Reset CLOCAL when CRTSCTS is set Signed-off-by: Johannes Thumshirn <johannes.thumshirn@men.de> Reviewed-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02serial: core: Simplify console suspend logic in uart_suspend_port()Peter Hurley
When the uart port being suspended is a console and consoles are not suspending (kernel command line contains no_console_suspend), then no action is performed for that port, and the function can return early. If the function has not returned early, then one of the conditions is not true, so the expression (console_suspend_enabled || !uart_console(uport)) must be true and can be eliminated. Similarly, the expression (console_suspend_enabled && uart_console(uport)) simplifies to just uart_console(uport). Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02serial: samsung: Add support for early consoleTomasz Figa
This patch adds support for early console initialized from device tree and kernel command line to all variants of Samsung serial driver. Signed-off-by: Tomasz Figa <t.figa@samsung.com> [mszyprow: added support for command line based initialization, fixed comments, added documentation] Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com> Tested-by: Alim Akhtar <alim.akhtar@samsung.com> Tested-by: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02serial: sh-sci: Fix R-Car SCIF and HSCIF overrun handlingHisashi Nakamura
When fifo overrun happened, the interrupt status refers to SCLSR register in R-Car SCIF and HSCIF. Thus, overrun handling takes SCLSR register into account. Signed-off-by: Hisashi Nakamura <hisashi.nakamura.ak@renesas.com> Signed-off-by: Yoshihiro Kaneko <ykaneko0929@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02serial: sh-sci: Use dev_dbg() to log an error messageYoshihiro Kaneko
Since the driver cannot return from overrun error if characters are output during overrun process, use dev_dbg() instead of dev_notice() to log the error message of overrun in syslog. Based on a patch by Hisashi Nakamura. Signed-off-by: Yoshihiro Kaneko <ykaneko0929@gmail.com> Acked-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02serial: 8250_dma: don't bother DMA with small transfersAndy Shevchenko
If we would like to send amount of data less than FIFO size we better would do this via PIO mode. Otherwise the overhead could be significant. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02serial: 8250_core: remove redundant else keywordAndy Shevchenko
Since we return in the first branch the second one doesn't require an additional else keyword. The patch removes it. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02sh-sci: extend PM methodsSergei Shtylyov
In order to make it possible to restore from hibernation not only in Linux but also in e.g. U-Boot, we have to use sci_{suspend|remove}() for the PM {freeze| thaw|restore}() methods. It's handy to achieve this by using SIMPLE_DEV_PM_OPS() macro, however we have to annotate sci_{suspend|remove}() with '__maybe_unused' in order to avoid compilation warnings when CONFIG_PM_SLEEP is undefined. Based on orignal patch by Mikhail Ulyanov <mikhail.ulyanov@cogentembedded.com>. Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02tty: xuartps: Fix RX hang, and TX corruption in termios callNathan Rossi
The implementation of flushing the RX FIFO breaks in a number of cases, it is impossible to ensure an complete flush of the RX FIFO due to the hardware not allowing the use of the FIFOs when the receiver is disabled (Reading from the FIFO register does not remove it from the FIFO when the RX_EN=0 or RX_DIS=1). Additionally during an initial set_termios call where RX_DIS=1 causes a hang waiting forever for the RX FIFO to empty. On top of this the FIFO will be cleared by the use of the RXRST bits on the Control Register, making the RX flush pointless (as it does not preserve the data read anyway). Due to the TXRST the TX FIFO and transmitter can be interrupted during frame trasmission, causing corruption and additionally data lost in the FIFO. Most other serial drivers do not flush or clear the FIFOs during a termios configuration change and as such do not have issues with corruption. For this UART controller is it required that the TXRST/RXRST bit be flagged during the change, this means that the data in the FIFO will be dropped when changing configuration. In order to prevent data loss and corruption of the transmitted data, wait until the TX FIFO is empty before changing the configuration. The performance of this may cause the set_termios call to take a longer amount of time especially on lower baud rates, however it is comparable to the same performance hit that a console_write call costs. Signed-off-by: Nathan Rossi <nathan.rossi@xilinx.com> Acked-by: Anirudha Sarangi <anirudh@xilinx.com> Acked-by: Harini Katakam <harinik@xilinx.com> Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02serial: mxs-auart: Remove unneeded zeroing of 'ret'Fabio Estevam
There is no need to explicitly zero the 'ret' variable as it is properly initialized in a few lines below as: ret = serial_mxs_probe_dt(s, pdev); Remove the unneeded zeroing of 'ret'. Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02serial: mxs-auart: Check for platform_get_irq() errorFabio Estevam
We should check whether platform_get_irq() failed, and in the case of error this needs to be propagated. Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02serial: mxs-auart: Remove irq from private structureFabio Estevam
The irq number is only used inside the probe function, so there is no need to keep it in the private mxs_auart_port structure. Use a local 'irq' variable for storing the irq number instead. Also make its type of 'int' as platform_get_irq() may fail and return a negative number. Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02tty/serial: digicolor: remove sysrq referenceBaruch Siach
The Digicolor USART hardware does not support detecting the BREAK condition. This means that we can't support sysrq on this hardware. Remove all reference to sysrq from the code. This also fixes build when sysrq is disabled: drivers/tty/serial/digicolor-usart.c: In function 'digicolor_uart_console_write': drivers/tty/serial/digicolor-usart.c:407:33: error: 'struct uart_port' has no member named 'sysrq' Reported-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Baruch Siach <baruch@tkos.co.il> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02serial: 8250_pnp: Enable PNP_CONSOLE for console portsPeter Hurley
When the kernel command line parameter, no_console_suspend, is used, the console should continue to output console messages during and after system suspend. For a serial console, the serial core ensures that the device is not shutdown when no_console_suspend is specified. However, the default operation of the pnp bus will disable and suspend the device and no further output occurs. When registering the 8250 port, if the serial device is a console set the PNP_CONSOLE capability, which prevents device power-off if consoles are not suspending. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02tty: serial: msm_serial: Remove console unregistration from driver exit.Pramod Gurav
unregister_console() will be called from uart_remove_one_port() while removing the platform driver. So not necessary to call it in driver exit path. Signed-off-by: Pramod Gurav <pramod.gurav@smartplayin.com> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02tty: serial: msm_serial: code cleanup in msm_console_setupPramod Gurav
The change does following: - baud, flow, bits, parity were being overwritten as they were being reinitialized after parsing. Initialize them when they are declared so that user provided setting are not overwritten. - msm_set_baud_rate() is anyway called in uart_set_options when it calls msm_set_termios(). msm_reset() is called when we change the baud rate. Hence doing away with both of these calls. - CR_CMD_PROTECTION_EN and CR_TX_ENABLE settings are done in msm_set_baud_rate. So do away with this here. Signed-off-by: Pramod Gurav <pramod.gurav@smartplayin.com> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02serial: 8250_pci: remove one useless explicit type conversionHeikki Krogerus
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02x86, mrst: remove Moorestown specific serial driversAndy Shevchenko
Intel Moorestown platform support was removed few years ago. This is a follow up which removes Moorestown specific code for the serial devices. It includes mrst_max3110 and earlyprintk bits. This was used on SFI (Medfield, Clovertrail) based platforms as well, though new ones use normal serial interface for the console service. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: David Cohen <david.a.cohen@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02serial: imx: Fix imx_flush_buffer()Fabio Estevam
When running an userspace program that does a 'tcflush(fd, TCIOFLUSH)' call we still see the last received character in the URXD register afterwards. Clear UCR2_SRST bit so that the UART FIFO is flushed properly. Since UCR2_SRST also resets some UART registers, we need to save and restore some of them. Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com> Tested-by: Fugang Duan <B38611@freescale.com> Acked-by: Jason Liu <r64343@freecale.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02tty: serial: fsl_lpuart: terminate DMA on buffer flushStefan Agner
On uart buffer flush, serial core resets the circular buffer. If a DMA transfer is in progress at that time, the callback lpuart_dma_tx_complete will move buffer's tail unconditionally, hence tail moves beyond head. Use the flush_buffer hook to terminate the DMA imeaditely and avoid lpuart_dma_tx_complete being called in this situation. This bug often showed up while shutdown and lead to duplicate serial console output. Signed-off-by: Stefan Agner <stefan@agner.ch> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02serial: fsl-lpuart: disable interrupt when suspendYuan Yao
For power management support, we should disable TX and TX interrupt so that kernel can prepare for deep sleep. Retain RX and RX interrupt for wakeup the kernel when receive the input character. Signed-off-by: Yuan Yao <yao.yuan@freescale.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02serial: fsl_lpuart: update RX timer on successful DMA transferStefan Agner
To end a DMA transfer which did not consume a whole buffer (e.g. one character only), a RX timer is used. When lots of data are received the DMA transfer will complete and setup another DMA transfer, which in turn might complete again. In this cases, it is not necessary to abort the DMA transfers using the RX timer. This change pushes the RX timer timeout into the future each time a DMA transfer completed. Aborting the DMA was not very harmful, since the next received character lead to setup of another RX DMA. Signed-off-by: Stefan Agner <stefan@agner.ch> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02serial: fsl_lpuart: move DMA channel request to probeStefan Agner
Move the DMA channel request to probe to avoid requesting the DMA channel on each opening of the ttyLPx device. This also fixes a potential issue that TX channel is not freed when only RX channel allocation fails. The DMA channels are now handled independently, so one could use UART with DMA only in TX direction for instance. Signed-off-by: Stefan Agner <stefan@agner.ch> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02serial: fsl_lpuart: avoid new transfer while DMA is runningStefan Agner
When the UART is in DMA receive mode (RDMAS set) and one character just arrived while another interrupt is handled (e.g. TX), the RDRF (receiver data register full flag) is set due to the water level of 1. But since the DMA will take care of this character, there is no need to handle it by calling lpuart_prepare_rx. Handling it leads to adding the RX timeout timer twice: [ 74.336698] Kernel BUG at 80053070 [verbose debug info unavailable] [ 74.342999] Internal error: Oops - BUG: 0 [#1] ARM0:00.00 khungtaskd [ 74.347817] Modules linked in: 0 S 0.0 0.0 0:00.00 writeback [ 74.350926] CPU: 0 PID: 0 Comm: swapper Not tainted 3.19.0-rc3-00001-g39d78e2 #1788 [ 74.358617] Hardware name: Freescale Vybrid VF610 (Device Tree)t [ 74.364563] task: 807a7678 ti: 8079c000 task.ti: 8079c000 kblockd [ 74.370002] PC is at add_timer+0x24/0x28.0 0.0 0:00.09 kworker/u2:1 [ 74.373960] LR is at lpuart_int+0x15c/0x3d8 [ 74.378171] pc : [<80053070>] lr : [<802e0d88>] psr: a0010193 [ 74.378171] sp : 8079de10 ip : 8079de20 fp : 8079de1c [ 74.389694] r10: 807d44c0 r9 : 8688c300 r8 : 00000013 [ 74.394943] r7 : 20010193 r6 : 00000000 r5 : 000000a0 r4 : 86997210 [ 74.401498] r3 : ffffa7da r2 : 80817868 r1 : 86997210 r0 : 86997344 [ 74.408052] Flags: NzCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment kernel [ 74.415489] Control: 10c5387d Table: 8611c059 DAC: 00000015 [ 74.421265] Process swapper (pid: 0, stack limit = 0x8079c230) ... Solve this by only execute the receiver path (lpuart_prepare_rx) if the DMA receive mode (RDMAS) is not set. Also, make sure the flag is cleared on initialization, in case it has been left set. This can be best reproduced using UART as a serial console, then running top while dd'ing data into the terminal. Signed-off-by: Stefan Agner <stefan@agner.ch> Cc: stable <stable@vger.kernel.org> # 3.14 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02serial: fsl_lpuart: delete timer on shutdownStefan Agner
If the serial port gets closed while a RX transfer is in progress, the timer might fire after the serial port shutdown finished. This leads in a NULL pointer dereference: [ 7.508324] Unable to handle kernel NULL pointer dereference at virtual address 00000000 [ 7.516590] pgd = 86348000 [ 7.519445] [00000000] *pgd=86179831, *pte=00000000, *ppte=00000000 [ 7.526145] Internal error: Oops: 17 [#1] ARM [ 7.530611] Modules linked in: [ 7.533876] CPU: 0 PID: 123 Comm: systemd Not tainted 3.19.0-rc3-00004-g5b11ea7 #1778 [ 7.541827] Hardware name: Freescale Vybrid VF610 (Device Tree) [ 7.547862] task: 861c3400 ti: 86ac8000 task.ti: 86ac8000 [ 7.553392] PC is at lpuart_timer_func+0x24/0xf8 [ 7.558127] LR is at lpuart_timer_func+0x20/0xf8 [ 7.562857] pc : [<802df99c>] lr : [<802df998>] psr: 600b0113 [ 7.562857] sp : 86ac9b90 ip : 86ac9b90 fp : 86ac9bbc [ 7.574467] r10: 80817180 r9 : 80817b98 r8 : 80817998 [ 7.579803] r7 : 807acee0 r6 : 86989000 r5 : 00000100 r4 : 86997210 [ 7.586444] r3 : 86ac8000 r2 : 86ac9bc0 r1 : 86997210 r0 : 00000000 [ 7.593085] Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user [ 7.600341] Control: 10c5387d Table: 86348059 DAC: 00000015 [ 7.606203] Process systemd (pid: 123, stack limit = 0x86ac8230) Setup the timer on UART startup which allows to delete the timer unconditionally on shutdown. This also saves the initialization on each transfer. Signed-off-by: Stefan Agner <stefan@agner.ch> Cc: stable <stable@vger.kernel.org> # 3.14 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-01-19Merge 3.19-rc5 into tty-nextGreg Kroah-Hartman
We want those tty fixes in that release in this branch as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-01-09serial: 8250_early: optimize early 8250 uartVineet Gupta
In early 8250, IER is already zero so no point in writing this - twice per line This helped improve the SystemC model based ARC OSCI platform Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jslaby@suse.cz> Cc: linux-serial@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: Rob Herring <robh@kernel.org> Cc: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-01-09tty: 8250: Add 64byte UART support for FSL platformsVijay Rai
Some of FSL SoCs like T1040 has new version of UART controller which can support 64byte FiFo. To enable 64 byte support, following needs to be done: -FCR[EN64] needs to be programmed to 1 to enable it. -Also, when FCR[EN64]==1, RTL bits to be used as below to define various Receive Trigger Levels: -FCR[RTL] = 00 1 byte -FCR[RTL] = 01 16 bytes -FCR[RTL] = 10 32 bytes -FCR[RTL] = 11 56 bytes -tx_loadsz is set to 63-bytes instead of 64-bytes to implement workaround of errata A-008006 which states that tx_loadsz should be configured less than Maximum supported fifo bytes Signed-off-by: Vijay Rai <vijay.rai@freescale.com> Signed-off-by: Priyanka Jain <Priyanka.Jain@freescale.com> Signed-off-by: Poonam Aggrwal <poonam.aggrwal@freescale.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-01-09serial: driver for Conexant Digicolor USARTBaruch Siach
Signed-off-by: Baruch Siach <baruch@tkos.co.il> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-01-09serial: imx: ignore framing errors when IGNPAR is set.Eric Nelson
When IGNPAR is set in termios->c_iflag, characters with framing errors should be ignored. Signed-off-by: Eric Nelson <eric.nelson@boundarydevices.com> Reviewed-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-01-09serial: imx: preserve characters with parity or framing errorsEric Nelson
If IGNPAR/INPCK are clear in termios->c_iflag, characters received with parity or framing errors should be preserved and passed to the upper layers of the tty stack. Specifically, the decision of whether to set the character value to zero should be made by n_tty.c/n_tty_receive_parity_error(). Signed-off-by: Eric Nelson <eric.nelson@boundarydevices.com> Reviewed-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-01-09serial: altera-uart: fix NULL device in log messageLey Foon Tan
Add device pointer to port->dev. Before: "(NULL device *): ttyAL0 at MMIO 0x2020 (irq = 6, base_baud = 3125000) is a Altera UART" After: "altera_uart 2020.serial: ttyAL0 at MMIO 0x2020 (irq = 6, base_baud = 3125000) is a Altera UART" Signed-off-by: Ley Foon Tan <lftan@altera.com> Acked-by: Tobias Klauser <tklauser@distanz.ch> Acked-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-01-09serial: altera-juart: fix NULL device in log messageLey Foon Tan
Add device pointer to port->dev. Before: "(NULL device *): ttyJ0 at MMIO 0x1008 (irq = 2, base_baud = 0) is a Altera JTAG UART" After: "altera_jtaguart 1008.serial: ttyJ0 at MMIO 0x1008 (irq = 2, base_baud = 0) is a Altera JTAG UART" Signed-off-by: Ley Foon Tan <lftan@altera.com> Acked-by: Tobias Klauser <tklauser@distanz.ch> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>