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path: root/drivers/tty/serial
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2018-03-09serial: imx: don't prepare to send if no data is availableUwe Kleine-König1-0/+3
serial_core might call the .start_tx callback without any data being available to send. In this case return early instead of going through all the setup needed for sending which might include disabling RX in RS485 half-duplex mode. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-09serial: imx: Fix handling of TC irq in combination with DMAUwe Kleine-König1-6/+20
When using RS485 half duplex the Transmitter Complete irq is needed to determine the moment when the transmitter can be disabled. When using DMA this irq must only be enabled when DMA has completed to transfer all data. Otherwise the CPU might busily trigger this irq which is not properly handled and so the also pending irq for the DMA transfer cannot trigger. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-09serial: imx: Also enable the aging timer in PIO modeUwe Kleine-König1-3/+12
This allows to increase the RX waterlevel which allows to delay the RRDY irq. The desired effect is that less irqs are needed to handle characters and so reduce irq count of the system. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-09serial: imx: ensure that RX irqs are off if RX is offUwe Kleine-König1-28/+64
Make sure that UCR1.RXDMAEN and UCR1.ATDMAEN (for the DMA case) and UCR1.RRDYEN (for the PIO case) are off iff UCR1.RXEN is disabled. This ensures that the fifo isn't read with RX disabled which results in an exception. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-09serial: imx: Stop to receive in .stop_rx()Uwe Kleine-König1-9/+0
When the UART is used in DMA mode, .stop_rx() does nothing if the port isn't suspended. This is wrong as .stop_rx() should stop receiving characters unconditionally. When the port is about to be closed the DMA channel is stopped in .shutdown(), so this isn't necessary to be in .stop_rx() here, too. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-09serial: imx: setup fifo waterlevel before enabling aging timerUwe Kleine-König1-2/+2
The aging timer fires if there are characters in the RX fifo but the water level isn't reached yet. Make sure that the waterlevel is configured before the aging timer is enabled to trigger a DMA request (UCR1_ATDMAEN). Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-09serial: imx: use u32 variables with matching names for registersUwe Kleine-König1-167/+179
The serial/imx driver is full of inconsistently named and typed variables that hold different register values. Consistently use u32 as type (matching what readl and writel use) and name the variables after the register whose value they are holding. This makes it easier to notice when UCR2_RTSEN is written to UCR1. The only difference introduced by this commit in the compiled driver is that twice the second argument to warn_slowpath_null() changed because the two WARN_ON in dma_rx_callback() pass __LINE__ to warn_slowpath_null(). Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-09serial: imx: simplify check that prevents starting PIO when DMA is in useUwe Kleine-König1-2/+1
The original code looks as follows: if (sport->dma_is_enabled) { ... make sure TX DMA is running, i.e. .dma_is_txing = 1 } if (sport->dma_is_txing) return; As .dma_is_txing can only be true if .dma_is_enabled is, the return can go at the end of the first if body without an additional check. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-09serial: imx: simplify some conditions related to dmaUwe Kleine-König1-3/+3
Neither .dma_is_txing nor .dma_is_rxing can evaluate to true if .dma_is_enabled evaluates to false: The only function that sets .dma_is_txing to a non-zero value is imx_dma_tx() which is only called if .dma_is_enabled is true. Same for .dma_is_rxing and start_rx_dma(). And before .dma_is_enabled is set to 0 when imx_shutdown calls imx_disable_dma(), .dma_is_rxing and .dma_is_txing are reset to zero before, too. For this reason sport->dma_is_enabled && sport->dma_is_rxing has the same value as sport->dma_is_rxing which allows to simplify three if conditions. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-09serial: imx: implement shadow registers for UCRx and UFCRUwe Kleine-König1-1/+59
This reduces the amount of read accesses to the register space by shadowing the values for five registers that only change on writing them. There is a single bit in UCR2 that might change without being written to it, this is handled accordingly. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-09serial: imx: add wrappers for writel and readlUwe Kleine-König1-184/+199
This prepares implementing shadow copies for the control registers and additionally provides a good place to hook in debug code to trace register usage. Most of this patch was done using pattern substitution: perl -p -i -e ' s/\breadl(?:_relaxed)?\((?:sport->port\.|port->)membase \+/imx_uart_readl(sport,/; s/\bwritel(?:_relaxed)?\(([^,]*), (sport->port\.|port->)membase \+/imx_uart_writel(sport, $1,/; ' drivers/tty/serial/imx.c Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28serial: imx: document functions that are called with port.lock takenUwe Kleine-König1-12/+11
Consistently indicate being called with irqs off and the port lock taken for all functions that this applies to. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28serial: imx: Rename register fields to match newer reference manualsUwe Kleine-König1-9/+9
Only the reference manual for the i.MX1 (I have MC9328MX1RM/D Rev 5 from 2004) uses TDMAEN and RDMAEN for these. All reference manuals for the newer chips use TXDMAEN and RXDMAEN. Update to the newer name with the assumption that most imx users don't use an imx1 any more. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28serial, pci_ids: Move duplicate IDs to PCI IDs databaseAndy Shevchenko1-3/+0
PCI ID database is for IDs used across several drivers. Here is the case for SUNIX combo cards. No functional change intended. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28serial: xuartps: Fix out-of-bounds access through DT aliasGeert Uytterhoeven1-1/+1
The cdns_uart_port[] array is indexed using a value derived from the "serialN" alias in DT, which may lead to an out-of-bounds access. Fix this by adding a range check. Fixes: 928e9263492069ee ("tty: xuartps: Initialize ports according to aliases") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28serial: sirf: Fix out-of-bounds access through DT aliasGeert Uytterhoeven1-0/+5
The sirf_ports[] array is indexed using a value derived from the "serialN" alias in DT, which may lead to an out-of-bounds access. Fix this by adding a range check. Fixes: a6ffe8966acbb66b ("serial: sirf: use dynamic method allocate uart structure") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28serial: sh-sci: Fix out-of-bounds access through DT aliasGeert Uytterhoeven1-0/+4
The sci_ports[] array is indexed using a value derived from the "serialN" alias in DT, which may lead to an out-of-bounds access. Fix this by adding a range check. Note that the array size is defined by a Kconfig symbol (CONFIG_SERIAL_SH_SCI_NR_UARTS), so this can even be triggered using a legitimate DTB. Fixes: 97ed9790c514066b ("serial: sh-sci: Remove unused platform data capabilities field") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28serial: samsung: Fix out-of-bounds access through serial port indexGeert Uytterhoeven1-0/+4
The s3c24xx_serial_ports[] array is indexed using a value derived from the "serialN" alias in DT, or from an incrementing probe index, which may lead to an out-of-bounds access. Fix this by adding a range check. Note that the array size is defined by a Kconfig symbol (CONFIG_SERIAL_SAMSUNG_UARTS), so this can even be triggered using a legitimate DTB or legitimate board code. Fixes: 13a9f6c64fdc55eb ("serial: samsung: Consider DT alias when probing ports") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28serial: pxa: Fix out-of-bounds access through serial port indexGeert Uytterhoeven1-0/+4
The serial_pxa_ports[] array is indexed using a value derived from the "serialN" alias in DT, or from platform data, which may lead to an out-of-bounds access. Fix this by adding a range check. Fixes: 699c20f3e6310aa2 ("serial: pxa: add OF support") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28serial: mxs-auart: Fix out-of-bounds access through serial port indexGeert Uytterhoeven1-0/+4
The auart_port[] array is indexed using a value derived from the "serialN" alias in DT, or from platform data, which may lead to an out-of-bounds access. Fix this by adding a range check. Fixes: 1ea6607d4cdc9179 ("serial: mxs-auart: Allow device tree probing") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28serial: imx: Fix out-of-bounds access through serial port indexGeert Uytterhoeven1-0/+6
The imx_ports[] array is indexed using a value derived from the "serialN" alias in DT, or from platform data, which may lead to an out-of-bounds access. Fix this by adding a range check. Fixes: ff05967a07225ab6 ("serial/imx: add of_alias_get_id() reference back") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28serial: fsl_lpuart: Fix out-of-bounds access through DT aliasGeert Uytterhoeven1-0/+4
The lpuart_ports[] array is indexed using a value derived from the "serialN" alias in DT, which may lead to an out-of-bounds access. Fix this by adding a range check. Fixes: c9e2e946fb0ba5d2 ("tty: serial: add Freescale lpuart driver support") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28serial: arc_uart: Fix out-of-bounds access through DT aliasGeert Uytterhoeven1-0/+5
The arc_uart_ports[] array is indexed using a value derived from the "serialN" alias in DT, which may lead to an out-of-bounds access. Fix this by adding a range check. Note that the array size is defined by a Kconfig symbol (CONFIG_SERIAL_ARC_NR_PORTS), so this can even be triggered using a legitimate DTB. Fixes: ea28fd56fcde69af ("serial/arc-uart: switch to devicetree based probing") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28serial: imx: drop check for enabled dma in .startupUwe Kleine-König1-1/+1
imx_shutdown() calls imx_disable_dma if .dma_is_enabled. So after imx_shudown() completes, .dma_is_enabled is zero. For this reason .dma_is_enabled is also zero when imx_startup() is called. So the check for this variable being zero can be dropped. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Reviewed-by: Shawn Guo <shawnguo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28serial: imx: simplify tracking of dma being initializedUwe Kleine-König1-8/+4
The .dma_is_inited member is only set to a value != 0 when the port's startup function calls imx_uart_dma_init(). On shutdown of the port imx_uart_dma_exit is called which sets the value back to 0. So .dma_is_inited is always 0 when imx_startup() is called (assuming .startup() and .shutdown() are correctly balanced) and the check for !sport->dma_is_inited can go away. This allows to replace .dma_is_inited by a variable local to imx_startup. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Reviewed-by: Shawn Guo <shawnguo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28serial: imx: Only handle irqs that are actually enabledUwe Kleine-König1-6/+32
Handling an irq that isn't enabled can have some undesired side effects. Some of these are mentioned in the newly introduced code comment. Some of the irq sources already had their handling right, some don't. Handle them all in the same consistent way. The change for USR1_RRDY and USR1_AGTIM drops the check for dma_is_enabled. This is correct as UCR1_RRDYEN and UCR2_ATEN are always off if dma is enabled. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Reviewed-by: Shawn Guo <shawnguo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28serial: imx: rename variables to match the register namesUwe Kleine-König1-11/+10
Now the variable holding the value of register USR1 is called usr1 instead of sts which is more straight forward. The same is also done for sts2 which is called usr2 now. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Reviewed-by: Shawn Guo <shawnguo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28serial: imx: drop if that always evaluates to trueUwe Kleine-König1-2/+1
The check sts & USR1_DTRD was just evaluated to true two lines above. So this change doesn't have any effect on the semantic of the driver. Fixes: 27e16501052e ("serial: imx: implement DSR irq handling for DTE mode") Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Reviewed-by: Shawn Guo <shawnguo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28serial: imx: fix bogus dev_errphil eichinger1-1/+1
Only one of the two is really required, not both: * have_rtscts or * have_rtsgpio In imx_rs485_config() this is done correctly, so RS485 is working, just the error message is false. Signed-off-by: Phil Eichinger <phil@zankapfel.net> Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com> Fixes: b8f3bff057b0 ("serial: imx: Support common rs485 binding for RTS polarity" Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28serial: sh-sci: prevent lockup on full TTY buffersUlrich Hecht1-0/+2
When the TTY buffers fill up to the configured maximum, a system lockup occurs: [ 598.820128] INFO: rcu_preempt detected stalls on CPUs/tasks: [ 598.825796] 0-...!: (1 GPs behind) idle=5a6/2/0 softirq=1974/1974 fqs=1 [ 598.832577] (detected by 3, t=62517 jiffies, g=296, c=295, q=126) [ 598.838755] Task dump for CPU 0: [ 598.841977] swapper/0 R running task 0 0 0 0x00000022 [ 598.849023] Call trace: [ 598.851476] __switch_to+0x98/0xb0 [ 598.854870] (null) This can be prevented by doing a dummy read of the RX data register. This issue affects both HSCIF and SCIF ports. Reported for R-Car H3 ES2.0; reproduced and fixed on H3 ES1.1. Probably affects other R-Car platforms as well. Reported-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Signed-off-by: Ulrich Hecht <ulrich.hecht+renesas@gmail.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Cc: stable <stable@vger.kernel.org> Tested-by: Nguyen Viet Dung <dung.nguyen.aj@renesas.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28serial: 8250_pci: Add Brainboxes UC-260 4 port serial deviceNikola Ciprich1-0/+11
Add PCI ids for two variants of Brainboxes UC-260 quad port PCI serial cards. Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Nikola Ciprich <nikola.ciprich@linuxbox.cz> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28earlycon: add reg-offset to physical address before mappingGreentime Hu1-1/+2
It will get the wrong virtual address because port->mapbase is not added the correct reg-offset yet. We have to update it before earlycon_map() is called Signed-off-by: Greentime Hu <greentime@andestech.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: stable@vger.kernel.org Fixes: 088da2a17619 ("of: earlycon: Initialize port fields from DT properties") Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28serial: core: mark port as initialized in autoconfigSebastian Andrzej Siewior1-0/+2
This is a followup on 44117a1d1732 ("serial: core: mark port as initialized after successful IRQ change"). Nikola has been using autoconfig via setserial and reported a crash similar to what I fixed in the earlier mentioned commit. Here I do the same fixup for the autoconfig. I wasn't sure that this is the right approach. Nikola confirmed that it fixes his crash. Fixes: b3b576461864 ("tty: serial_core: convert uart_open to use tty_port_open") Link: http://lkml.kernel.org/r/20180131072000.GD1853@localhost.localdomain Reported-by: Nikola Ciprich <nikola.ciprich@linuxbox.cz> Tested-by: Nikola Ciprich <nikola.ciprich@linuxbox.cz> Cc: <stable@vger.kernel.org> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Tested-by: Nikola Ciprich <nikola.ciprich@linuxbox.cz> Acked-by: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28serial: 8250_pci: Don't fail on multiport card classAndy Shevchenko1-3/+7
Do not fail on multiport cards in serial_pci_is_class_communication(). It restores behaviour for SUNIX multiport cards, that enumerated by class and have a custom board data. Moreover it allows users to reenumerate port-by-port from user space. Fixes: 7d8905d06405 ("serial: 8250_pci: Enable device after we check black list") Reported-by: Nikola Ciprich <nikola.ciprich@linuxbox.cz> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Tested-by: Nikola Ciprich <nikola.ciprich@linuxbox.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28tty/serial: atmel: add new version check for usartJonas Danielsson1-0/+1
On our at91sam9260 based board the usart0 and usart1 ports report their versions (ATMEL_US_VERSION) as 0x10302. This version is not included in the current checks in the driver. Signed-off-by: Jonas Danielsson <jonas@orbital-systems.com> Acked-by: Richard Genoud <richard.genoud@gmail.com> Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28serial: mvebu-uart: remove duplicated bit-wise or of STAT_FRM_ERRColin Ian King1-1/+1
Bit pattern STAT_FRM_ERR is being bit-wise or'd twice; remove the redundant 2nd STAT_FRM_ERR Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28tty: serial: imx: allow breaks to be received when using dmaTroy Kisky1-7/+14
This allows me to login after sending a break when service serial-getty@ttymxc0.service is running The "tty_insert_flip_char(port, 0, TTY_BREAK)" in clear_rx_errors fixes this by allowing the higher layers to see a break. Also, call uart_handle_break to handle possible "secure attention key." FYI: Martin said the ROM sdma firmware works with this patch, but external sdma firmware still does not send breaks on a i.mx6UL Signed-off-by: Troy Kisky <troy.kisky@boundarydevices.com> Tested-by: Martin Hicks <mort@bork.org> Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com> Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28serial: 8250_dw: Allow TX FIFO to drain before writing to UART_LCRJoshua Scott1-0/+18
An issue has been observed on the Marvell Armada 38x serial port. Writes to UART_LCR can result in characters that are currently held in the TX FIFO being lost rather than sent, even if the userspace process has attempted to flush them. This is most visible when using the "resize" command (tested on Busybox), where we have observed the escape code for restoring cursor position becoming mangled. Signed-off-by: Joshua Scott <joshua.scott@alliedtelesis.co.nz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28serial: sh-sci: use hrtimer for receive timeoutUlrich Hecht1-17/+30
High latencies of classic timers cause performance issues for high- speed serial transmissions. This patch transforms rx_timer into an hrtimer to reduce the minimum latency. Signed-off-by: Ulrich Hecht <ulrich.hecht+renesas@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28serial: 8250: 8250_omap: Fix throttling when DMA is enabledVignesh R1-1/+10
omap_8250_throttle() is called when tty RX buffer is about to overflow and can no longer keep up with the rate at which UART is receiving data. So, the expectation of this callback, is that UART stops RX and asserts HW flow control to signal the sender to stop sending more data. omap_8250_throttle() disables RX FIFO interrupts thus FIFO is no longer serviced, leading to assertion of flow control once RX FIFO is full. But, this does not work when DMA is enabled as driver keeps queuing new RX DMA request in completion handler without brothering about throttling request made by the higher layer. This patch introduces a flag that can be used to determine whether or not to queue next RX DMA request based on throttling request. Without this patch, tty buffer overflows are reported at higher baudrates. Signed-off-by: Vignesh R <vigneshr@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28serial: 8250: Don't service RX FIFO if interrupts are disabledVignesh R1-1/+2
Currently, data in RX FIFO is read based on UART_LSR register state even if RDI and RLSI interrupts are disabled in UART_IER register. This is because when IRQ handler is called due to TX FIFO empty event, RX FIFO is serviced based on UART_LSR register status instead of UART_IIR status. This defeats the purpose of disabling UART RX FIFO interrupts during throttling(see, omap_8250_throttle()) as IRQ handler continues to drain UART RX FIFO resulting in overflow of buffer at tty layer. Fix this by making sure that driver drains UART RX FIFO only when UART_IIR_RDI is set along with UART_LSR_BI or UART_LSR_DR bits. Signed-off-by: Vignesh R <vigneshr@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28gpio: serial: max310x: Use HW type for gpio_chip's labelJan Kundrát1-1/+1
Some debugging tools (/sys/kernel/debug/gpio, `lsgpio`) use the gpio_chip's label for displaying an additional context. Right now, the information duplicates stuff which is already available from the parent's device. This is how e.g. `lsgpio`'s output looks like: GPIO chip: gpiochip2, "spi1.2", 16 GPIO lines Comparing the output of other GPIO expanders that I have available: gpiochip4: GPIOs 464-479, parent: spi/spi1.1, mcp23s17, can sleep: gpiochip5: GPIOs 448-463, parent: i2c/0-0020, pca9555, can sleep: gpiochip2: GPIOs 496-511, parent: spi/spi1.2, spi1.2, can sleep: This patch ensures that the type of the real HW device is shown instead of duplicating the SPI path: gpiochip2: GPIOs 496-511, parent: spi/spi1.2, MAX14830, can sleep: Signed-off-by: Jan Kundrát <jan.kundrat@cesnet.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28serial: altera: set RRDY flag also without irqUwe Kleine-König1-9/+9
The UART can be operated without an irq. In this case a timer is setup that regularily calls altera_uart_interrupt(). The receiving part depends on pp->imr having the bit ALTERA_UART_STATUS_RRDY_MSK set, otherwise altera_uart_rx_chars() is never called. So ensure that the bit gets set (disguised as ALTERA_UART_CONTROL_RRDY_MSK) by not returning early from altera_uart_startup() if port->irq is 0. This doesn't affect the hardware as the ALTERA_UART_CONTROL_RRDY_MSK bit isn't actually written to the control register. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Acked-by: Tobias Klauser <tklauser@distanz.ch> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28serial: altera: don't enable any irq if the device doesn't feature an irqUwe Kleine-König1-8/+22
If the irq line of an altera UART device isn't used to report interrupts for this device the driver better ensures that this device doesn't pull this line to active state and so disturb the whatever might be connected to this line. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Acked-by: Tobias Klauser <tklauser@distanz.ch> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28serial: altera: ensure port->regshift is honored consistentlyUwe Kleine-König1-6/+6
Most register accesses in the altera driver honor port->regshift by using altera_uart_writel(). There are a few accesses however that were missed when the driver was converted to use port->regshift and some others were added later in commit 4d9d7d896d77 ("serial: altera_uart: add earlycon support"). Fixes: 2780ad42f5fe ("tty: serial: altera_uart: Use port->regshift to store bus shift") Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Acked-by: Tobias Klauser <tklauser@distanz.ch> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-09Merge tag 'acpi-part2-4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pmLinus Torvalds1-10/+5
Pull more ACPI updates from Rafael Wysocki: "These are mostly fixes and cleanups, a few new quirks, a couple of updates related to the handling of ACPI tables and ACPICA copyrights refreshment. Specifics: - Update the ACPICA kernel code to upstream revision 20180105 including: * Assorted fixes (Jung-uk Kim) * Support for X32 ABI compilation (Anuj Mittal) * Update of ACPICA copyrights to 2018 (Bob Moore) - Prepare for future modifications to avoid executing the _STA control method too early (Hans de Goede) - Make the processor performance control library code ignore _PPC notifications if they cannot be handled and fix up the C1 idle state definition when it is used as a fallback state (Chen Yu, Yazen Ghannam) - Make it possible to use the SPCR table on x86 and to replace the original IORT table with a new one from initrd (Prarit Bhargava, Shunyong Yang) - Add battery-related quirks for Asus UX360UA and UX410UAK and add quirks for table parsing on Dell XPS 9570 and Precision M5530 (Kai Heng Feng) - Address static checker warnings in the CPPC code (Gustavo Silva) - Avoid printing a raw pointer to the kernel log in the smart battery driver (Greg Kroah-Hartman)" * tag 'acpi-part2-4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: ACPI: sbshc: remove raw pointer from printk() message ACPI: SPCR: Make SPCR available to x86 ACPI / CPPC: Use 64-bit arithmetic instead of 32-bit ACPI / tables: Add IORT to injectable table list ACPI / bus: Parse tables as term_list for Dell XPS 9570 and Precision M5530 ACPICA: Update version to 20180105 ACPICA: All acpica: Update copyrights to 2018 ACPI / processor: Set default C1 idle state description ACPI / battery: Add quirk for Asus UX360UA and UX410UAK ACPI: processor_perflib: Do not send _PPC change notification if not ready ACPI / scan: Use acpi_bus_get_status() to initialize ACPI_TYPE_DEVICE devs ACPI / bus: Do not call _STA on battery devices with unmet dependencies PCI: acpiphp_ibm: prepare for acpi_get_object_info() no longer returning status ACPI: export acpi_bus_get_status_handle() ACPICA: Add a missing pair of parentheses ACPICA: Prefer ACPI_TO_POINTER() over ACPI_ADD_PTR() ACPICA: Avoid NULL pointer arithmetic ACPICA: Linux: add support for X32 ABI compilation ACPI / video: Use true for boolean value
2018-02-07ACPI: SPCR: Make SPCR available to x86Prarit Bhargava1-10/+5
SPCR is currently only enabled or ARM64 and x86 can use SPCR to setup an early console. General fixes include updating Documentation & Kconfig (for x86), updating comments, and changing parse_spcr() to acpi_parse_spcr(), and earlycon_init_is_deferred to earlycon_acpi_spcr_enable to be more descriptive. On x86, many systems have a valid SPCR table but the table version is not 2 so the table version check must be a warning. On ARM64 when the kernel parameter earlycon is used both the early console and console are enabled. On x86, only the earlycon should be enabled by by default. Modify acpi_parse_spcr() to allow options for initializing the early console and console separately. Signed-off-by: Prarit Bhargava <prarit@redhat.com> Acked-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Mark Salter <msalter@redhat.com> Tested-by: Mark Salter <msalter@redhat.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-02-01Merge tag 'driver-core-4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-coreLinus Torvalds1-1/+1
Pull driver core updates from Greg KH: "Here is the set of "big" driver core patches for 4.16-rc1. The majority of the work here is in the firmware subsystem, with reworks to try to attempt to make the code easier to handle in the long run, but no functional change. There's also some tree-wide sysfs attribute fixups with lots of acks from the various subsystem maintainers, as well as a handful of other normal fixes and changes. And finally, some license cleanups for the driver core and sysfs code. All have been in linux-next for a while with no reported issues" * tag 'driver-core-4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (48 commits) device property: Define type of PROPERTY_ENRTY_*() macros device property: Reuse property_entry_free_data() device property: Move property_entry_free_data() upper firmware: Fix up docs referring to FIRMWARE_IN_KERNEL firmware: Drop FIRMWARE_IN_KERNEL Kconfig option USB: serial: keyspan: Drop firmware Kconfig options sysfs: remove DEBUG defines sysfs: use SPDX identifiers drivers: base: add coredump driver ops sysfs: add attribute specification for /sysfs/devices/.../coredump test_firmware: fix missing unlock on error in config_num_requests_store() test_firmware: make local symbol test_fw_config static sysfs: turn WARN() into pr_warn() firmware: Fix a typo in fallback-mechanisms.rst treewide: Use DEVICE_ATTR_WO treewide: Use DEVICE_ATTR_RO treewide: Use DEVICE_ATTR_RW sysfs.h: Use octal permissions component: add debugfs support bus: simple-pm-bus: convert bool SIMPLE_PM_BUS to tristate ...
2018-01-25tty: serial: exar: Relocate sleep wake-up handlingAaron Sierra2-30/+30
Exar sleep wake-up handling has been done on a per-channel basis by virtue of INT0 being accessible from each channel's address space. I believe this was initially done out of necessity, but now that Exar devices have their own driver, we can do things more efficiently by registering a dedicated INT0 handler at the PCI device level. I see this change providing the following benefits: 1. If more than one port is active, eliminates the redundant bus cycles for reading INT0 on every interrupt. 2. This note associated with hooking in the per-channel handler in 8250_port.c is resolved: /* Fixme: probably not the best place for this */ Cc: Matt Schulte <matts@commtech-fastcom.com> Signed-off-by: Aaron Sierra <asierra@xes-inc.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-22serial: imx: fix endless loop during suspendMartin Kaiser1-17/+15
Before we go into suspend mode, we enable the imx uart's interrupt for the awake bit in the UART Status Register 1. If, for some reason, the awake bit is already set before we enter suspend mode, we get an interrupt immediately when we enable interrupts for awake. The uart's clk_ipg is disabled at this point (unless there's an ongoing transfer). We end up in the interrupt handler, which usually tries to clear the awake bit. This doesn't work with the clock disabled. Therefore, we keep getting interrupts forever, resulting in an endless loop. Clear the awake bit before setting the awaken bit to signal that we want an imx interrupt when the awake bit will be set. This ensures that we're not woken up by events that happened before we started going into suspend mode. Change the clock handling so that suspend prepares and enables the clock and suspend_noirq disables it. Revert these operations in resume_noirq and resume. With these preparations in place, we can now modify awake and awaken in the suspend function when the actual imx interrupt is disabled and the required clk_ipg is active. Update the thaw and freeze functions to use the new clock handling since we share the suspend_noirq function between suspend and hibernate. Signed-off-by: Martin Kaiser <martin@kaiser.cx> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>