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path: root/drivers/tty/serial/amba-pl011.c
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2015-03-11drivers/tty: serial: remove info messageJorge Ramirez-Ortiz1-1/+0
Unacceptable levels of debug info will happen when the DMA driver defined in the DT/ACPI is a blacklisted module. Another cause for log polution would be the defer probing of the DMA driver taking too long - in which case the message that this commit removes would be cluttering the logs due to the init daemons activity. Signed-off-by: Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@linaro.org> Reviewed-by: Rob Herring <robh@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-07drivers/tty: amba: defer DMA probe until the DMA channel is required.Jorge Ramirez-Ortiz1-54/+17
Fix a race condition that happens when device_initcall(pl011_dma_initicall) is executed before all the devices have been probed - this issue was observed on a hisi_6220 SoC (HiKey board from Linaro). The deferred driver probing framework relies on late_initcall to trigger deferred probes so it is just possible that, even with a valid DMA driver ready to be loaded, we fail to synchronize with it. The proposed implementation delays probing the DMA until dma_startup. As this is invoked on port startup and port resume - but DMA probing is only required once - we avoid calling multiple times using a new field in uart_amba_port to track this scenario. This commit allows for subsequent attempts to associate an external DMA if the DMA driver itself is not available (but present in the deferred probe pending list). Signed-off-by: Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@linaro.org> Reviewed-by: Rob Herring <robh@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-07serial/amba-pl011: Leave the TX IRQ alone when the UART is not openDave Martin1-4/+1
Getting the TX IRQ re-asserted from scratch can be inefficient in some setups. This patch avoids clearing the TX IRQ across pl011_shutdown()... pl011_startup(), so that if the port is closed and reopened, the IRQ will still work afterwards without having to bootstrap it again. The TX IRQ continues to be masked in IMSC when the UART is not in use. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Tested-by: Andre Przywara <andre.przywara@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-07serial/amba-pl011: Activate TX IRQ passivelyDave Martin1-50/+115
The current PL011 driver transmits a dummy character when the UART is opened, to assert the TX IRQ for the first time (see pl011_startup()). The UART is put in loopback mode temporarily, so the receiver presumably shouldn't see anything. However... At least some platforms containing a PL011 send characters down the wire even when loopback mode is enabled. This means that a spurious NUL character may be seen at the receiver when the PL011 is opened through the TTY layer. The current code also temporarily sets the baud rate to maximum and the character width to the minimum, to that the dummy TX completes as quickly as possible. If this is seen by the receiver it will result in a framing error and can knock the receiver out of sync -- turning subsequent output into garbage until synchronisation is reestablished. (Particularly problematic during boot with systemd.) To avoid spurious transmissions, this patch removes assumptions about whether the TX IRQ will fire until at least one TX IRQ has been seen. Instead, the UART will unmask the TX IRQ and then slow-start via polling and timer-based soft IRQs initially. If the TTY layer writes enough data to fill the FIFO to the interrupt threshold in one go, the TX IRQ should assert, at which point the driver changes to fully interrupt-driven TX. In this way, the TX IRQ is activated as a side-effect instead of being done deliberately. This should also mean that the driver works on the SBSA Generic UART[1] (a cut-down PL011) without invasive changes. The Generic UART lacks some features needed for the dummy TX approach to work (FIFO disabling and loopback). [1] Server Base System Architecture (ARM-DEN-0029-v2.3) http://infocenter.arm.com/ (click-thru required :/) Signed-off-by: Dave Martin <Dave.Martin@arm.com> Tested-by: Andre Przywara <andre.przywara@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-07serial: pl011: Add device tree support for RX DMA pollingAndrew Jackson1-3/+19
Add equivalent attributes to those provided in the platform data for use when RX DMA is enabled. Signed-off-by: Andrew Jackson <Andrew.Jackson@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-07serial: pl011: Don't enable RX DMA if residue processing not supportedAndrew Jackson1-0/+15
If the DMA engine doesn't support residue processing then the RX DMA handling won't work terribly well if polling is enabled. So, disable RX DMA if residue handling isn't available. Signed-off-by: Andrew Jackson <Andrew.Jackson@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-07serial: pl011: Set length of DMA transferAndrew Jackson1-0/+1
The DMA engines on some systems require that the dma_length is set when using scatter gather lists. Signed-off-by: Andrew Jackson <Andrew.Jackson@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-07serial: pl011: Avoid assumptions about buffer size when refilling TX DMAAndrew Jackson1-1/+5
The existing code assumed that PL011_DMA_BUFFER_SIZE == UART_XMIT_SIZE, which may not always be the case. This allows for these two being different sizes and not copying too much data. Signed-off-by: Andrew Jackson <Andrew.Jackson@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-07serial: pl011: Allocate TX DMA buffer from DMA capable memoryAndrew Jackson1-1/+1
Allocating with __GFP_DMA avoids the need for bounce buffers Signed-off-by: Andrew Jackson <Andrew.Jackson@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-06serial: pl011: Fix build breakage with !CONFIG_DMA_ENGINEPeter Hurley1-1/+2
Commit 479e9b94fdce7bc4 ("serial: Refactor uart_flush_buffer() from uart_close") refactored the uart_flush_buffer() in uart_close() into those drivers that define a flush_buffer() method. However, in the amba-pl011 driver configured without CONFIG_DMA_ENGINE, flush_buffer() is a NULL method, so the direct call fails to compile. Check and call the flush_buffer() method through the ops table instead. Reported-by: Fengguang Wu <fengguang.wu@intel.com> Cc: Russell King <linux@arm.linux.org.uk> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-05serial: Refactor uart_flush_buffer() from uart_close()Peter Hurley1-0/+1
In the context of the final tty & port close, flushing the tx ring buffer after the hardware has already been shutdown and the ring buffer freed is neither required nor desirable. uart_flush_buffer() performs 3 operations: 1. Resets tx ring buffer indices, but the tx ring buffer has already been freed and the indices are reset if the port is re-opened. 2. Calls uart driver's flush_buffer() method 5 in-tree uart drivers define flush_buffer() methods: amba-pl011, atmel-serial, imx, serial-tegra, timbuart These have been refactored into the shutdown() method, if required. 3. Kicks the ldisc for more writing, but this is undesirable. The file handle is being released; any waiting writer will will be kicked out by tty_release() with a warning. Further, the N_TTY ldisc may generate SIGIO for a file handle which is no longer valid. Cc: Nicolas Ferre <nicolas.ferre@atmel.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Laxman Dewangan <ldewangan@nvidia.com> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-08serial: amba-pl011: Use container_of() to get uart_amba_portDaniel Thompson1-18/+36
Universally adopt container_of() for all pointer conversion from uart_port to uart_amba_port. Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Jiri Slaby <jslaby@suse.cz> Cc: linux-serial@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-09serial: amba-pl011: Remove redundant labelTushar Behera1-20/+10
The label 'out' is only used to return the error code. We can return the error code directly and remove 'out' label. Signed-off-by: Tushar Behera <tushar.b@samsung.com> Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-06-19serial: Fix IGNBRK handlingPeter Hurley1-1/+1
If IGNBRK is set without either BRKINT or PARMRK set, some uart drivers send a 0x00 byte for BREAK without the TTYBREAK flag to the line discipline, when it should send either nothing or the TTYBREAK flag set. This happens because the read_status_mask masks out the BI condition, which uart_insert_char() then interprets as a normal 0x00 byte. SUS v3 is clear regarding the meaning of IGNBRK; Section 11.2.2, General Terminal Interface - Input Modes, states: "If IGNBRK is set, a break condition detected on input shall be ignored; that is, not put on the input queue and therefore not read by any process." Fix read_status_mask to include the BI bit if IGNBRK is set; the lsr status retains the BI bit if a BREAK is recv'd, which is subsequently ignored in uart_insert_char() when masked with the ignore_status_mask. Affected drivers: 8250 - all serial_txx9 mfd amba-pl010 amba-pl011 atmel_serial bfin_uart dz ip22zilog max310x mxs-auart netx-serial pnx8xxx_uart pxa sb1250-duart sccnxp serial_ks8695 sirfsoc_uart st-asc vr41xx_siu zs sunzilog fsl_lpuart sunsab ucc_uart bcm63xx_uart sunsu efm32-uart pmac_zilog mpsc msm_serial m32r_sio Unaffected drivers: omap-serial rp2 sa1100 imx icom Annotated for fixes: altera_uart mcf Drivers without break detection: 21285 xilinx-uartps altera_jtaguart apbuart arc-uart clps711x max3100 uartlite msm_serial_hs nwpserial lantiq vt8500_serial Unknown: samsung mpc52xx_uart bfin_sport_uart cpm_uart/core Fixes: Bugzilla #71651, '8250_core.c incorrectly handles IGNBRK flag' Reported-by: Ivan <athlon_@mail.ru> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-20tty/serial: pl011: add DT based earlycon supportRob Herring1-0/+1
Enable DT based earlycon initialization for the pl011 uart. Signed-off-by: Rob Herring <robh@kernel.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jslaby@suse.cz> Acked-by: Grant Likely <grant.likely@linaro.org>
2014-04-24tty/serial: pl011: add generic earlycon supportRob Herring1-1/+29
Add earlycon support for the pl011 serial port. This allows enabling the pl011 for console when early_params are processed. This is based on the arm64 earlyprintk support and is intended to replace it. Signed-off-by: Rob Herring <robh@kernel.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-16serial: amba-pl011: fix regression, causing an Oops on rmmodGuennadi Liakhovetski1-1/+5
A recent commit ef2889f7ffee67f0aed49e854c72be63f1466759 "serial: pl011: Move uart_register_driver call to device probe" introduced a regression, causing the pl011 driver to Oops if more than 1 port have been probed. Fix the Oops by only calling uart_unregister_driver() once after the last port has been removed. Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-16serial: pl011: change Rx burst size to half of trigger levelGuennadi Liakhovetski1-1/+1
The amba-pl011.c driver sets DMA burst size equal to FIFO trigger level. If now exactly DMA burst size bytes are received, the DMAC will retrieve them all and no Rx timeout interrupt will be generated. To fix that set the burst size to half the FIFO trigger level. Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-02-13serial: pl011: Move uart_register_driver call to device probeTushar Behera1-9/+12
uart_register_driver call binds the driver to a specific device node through tty_register_driver call. This should typically happen during device probe call. In a multiplatform scenario, it is possible that multiple serial drivers are part of the kernel. Currently the driver registration fails if multiple serial drivers with same default major/minor numbers are included in the kernel. A typical case is observed with amba-pl011 and samsung-uart drivers. Signed-off-by: Tushar Behera <tushar.behera@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-17serial: pl011: fix fall back from DMA to interrupt modeGuennadi Liakhovetski1-0/+2
When falling back from DMA to interrupt mode the receive interrupt has to be re-enabled to catch new incoming data. Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-17serial: pl011: (cosmetic) remove superfluous register writeGuennadi Liakhovetski1-3/+1
In pl011_rx_chars() if pl011_dma_rx_trigger_dma() succeeds it will disable the receive interrupt, no need to do this again. Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-17serial: amba-pl011: preseserve hardware settings during initialisationJon Medhurst1-2/+12
During initialisation, a UART may already be in use for a console, so take care to preserve things like baud rate and data format to avoid corrupting console output. Signed-off-by: Jon Medhurst <tixy@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-17serial: amba-pl011: factor out code for writing LCR_H registerJon Medhurst1-22/+17
The code to cope with a split tx/rx LCR_H register is non-trivial so put it into it's own function to avoid duplication. Signed-off-by: Jon Medhurst <tixy@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-17serial: amba-pl011: use port lock to guard control register accessJon Medhurst1-0/+6
When the pl011 is being used for a console, pl011_console_write forces the control register (CR) to enable the UART for transmission and then restores this to the original value afterwards. It does this while holding the port lock. Unfortunately, when the uart is started or shutdown - say in response to userland using the serial device for a terminal - then this updates the control register without any locking. This means we can have pl011_console_write Save CR pl011_startup Initialise CR, e.g. enable receive pl011_console_write Restore old CR with receive not enabled this result is a serial port which doesn't respond to any input. A similar race in reverse could happen when the device is shutdown. We can fix these problems by taking the port lock when updating CR. Signed-off-by: Jon Medhurst <tixy@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-17Revert "serial: pl011: use DMA RX polling by default"Greg Kroah-Hartman1-1/+1
This reverts commit 17438217a6f5e33d920ed3821a4b857311cc2872 on request of Linus Walleij: Greg can you please drop or revert commit 17438217a6f5e33d920ed3821a4b857311cc2872 "serial: pl011: use DMA RX polling by default" from the TTY tree until this has been sorted out? Cc: Linus Walleij <linus.walleij@linaro.org> Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-08serial: pl011: use DMA RX polling by defaultLinus Walleij1-1/+1
Making DMA RX polling optional when DMA is on was just over-cautious: there is one single system in the kernel tree using this facility, Ux500 and after some testing I turned this on also for Ux500, which means it should simply be on by default if DMA is enabled. Cc: Jongsung Kim <neidhard.kim@lge.com> Cc: Chanho Min <chanho.min@lge.com> Cc: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-08serial: pl011: Convert to modern PM opsUlf Hansson1-9/+8
Convert to modern PM ops and use the SIMPLE_DEV_PM_OPS macro to set up the PM callbacks. Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-08serial: pl011: remove redundant early amba_ports declarationBaruch Siach1-2/+0
This early amba_ports declaration was introduced by commit c16d51a32 (amba pl011: workaround for uart registers lockup) for use in the pl011_lockup_wa() routine. This routine was later removed by commit 4fd0690bb (serial: pl011: implement workaround for CTS clear event issue). Signed-off-by: Baruch Siach <baruch@tkos.co.il> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-03serial: Remove unnecessary amba_set_drvdata()Michal Simek1-3/+0
Driver core clears the driver data to NULL after device_release or on probe failure, so just remove it from here. Driver core change: "device-core: Ensure drvdata = NULL when no driver is bound" (sha1: 0998d0631001288a5974afc0b2a5f568bcdecb4d) Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-12serial: amba-pl011: Use __releases/__acquires annotationsFabio Estevam1-0/+4
Fix the following sparse warnings: drivers/tty/serial/amba-pl011.c:687:20: warning: context imbalance in 'pl011_dma_flush_buffer' - unexpected unlock drivers/tty/serial/amba-pl011.c:1200:13: warning: context imbalance in 'pl011_rx_chars' - unexpected unlock Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-31serial: use dev_get_platdata()Jingoo Han1-7/+7
Use the wrapper function for retrieving the platform data instead of accessing dev->platform_data directly. Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-03Merge tag 'pinctrl-for-v3.11-1' of ↵Linus Torvalds1-39/+3
git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl Pull pin control changes from Linus Walleij: - A large slew of improvements of the Genric pin configuration support, and deployment in four different platforms: Rockchip, Super-H PFC, ABx500 and TZ1090. Support BIAS_BUS_HOLD, get device tree parsing and debugfs support into shape. - We also have device tree support with generic naming conventions for the generic pin configuration. - Delete the unused and confusing direct pinconf API. Now state transitions is *the* way to control pins and multiplexing. - New drivers for Rockchip, TZ1090, and TZ1090 PDC. - Two pin control states related to power management are now handled in the device core: "sleep" and "idle", removing a lot of boilerplate code in drivers. We do not yet know if this is the final word for pin PM, but it already make things a lot easier to handle. - Handle sparse GPIO ranges passing a list of disparate pins, and utilize these in the new BayTrail (x86 Atom SoC) driver. - Make the sunxi (AllWinner) driver handle external interrupts. - Make it possible for pinctrl-single to handle the case where several pins are managed by a single register, and augment it to handle sleep modes. - Cleanups and improvements for the abx500 drivers. - Move Sirf pin control drivers to their own directory, support save/restore of context and add support for the SiRFatlas6 SoC. - PMU muxing for the Dove pinctrl driver. - Finalization and support for VF610 in the i.MX6 pinctrl driver. - Smoothen out various Exynos rough edges. - Generic cleanups of various kinds. * tag 'pinctrl-for-v3.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (82 commits) pinctrl: vt8500: wmt: remove redundant dev_err call in wmt_pinctrl_probe() pinctrl: remove bindings for pinconf options needing more thought pinctrl: remove slew-rate parameter from tz1090 pinctrl: set unit for debounce time pinconfig to usec pinctrl: more clarifications for generic pull configs pinctrl: rip out the direct pinconf API pinctrl-tz1090-pdc: add TZ1090 PDC pinctrl driver pinctrl-tz1090: add TZ1090 pinctrl driver pinctrl: samsung: Staticize drvdata_list pinctrl: rockchip: Add missing irq_gc_unlock() call before return error pinctrl: abx500: rework error path pinctrl: abx500: suppress hardcoded value pinctrl: abx500: factorize code pinctrl: abx500: fix abx500_gpio_get() pinctrl: abx500: fix abx500_pin_config_set() pinctrl: abx500: Add device tree support sh-pfc: Guard DT parsing with #ifdef CONFIG_OF pinctrl: add Intel BayTrail GPIO/pinctrl support pinctrl: fix pinconf_ops::pin_config_dbg_parse_modify kerneldoc pinctrl: Staticize local symbols ... Conflicts: drivers/net/ethernet/ti/davinci_mdio.c drivers/pinctrl/Makefile
2013-06-16tty: serial: modify PL011 driver to use pinctrl PM helpersLinus Walleij1-39/+3
This augments the PL011 UART driver to utilize the new pinctrl core PM helpers to transition the driver to default and sleep states, cutting away some boilerplate code. Cc: Hebbar Gururaja <gururaja.hebbar@ti.com> Cc: Mark Brown <broonie@kernel.org> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Kevin Hilman <khilman@linaro.org> Cc: Stephen Warren <swarren@wwwdotorg.org> Acked-by: Wolfram Sang <wsa@the-dreams.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-05-27Merge 3.10-rc3 into tty-nextGreg Kroah-Hartman1-1/+1
We want these fixes. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-20serial: pl011: protect attribute read from NULL platform data structLee Jones1-1/+1
It's completely feasible that platform data will be empty i.e. when booting with Device Tree with no device AUXDATA. So we must protect it's use in these use-cases, or risk a kernel Oops. Cc: Russell King <linux@arm.linux.org.uk> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Lee Jones <lee.jones@linaro.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-20tty: serial: amba-pl011: revise to use amba_rev macroJongsung Kim1-6/+5
This patch replaces the ugly bit-operations with the convenient amba_rev macro from the get_fifosize_arm function. The type of get_fifosize member function is also slightly changed to take a pointer to the amba_device. Signed-off-by: Jongsung Kim <neidhard.kim@lge.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-07Merge tag 'cleanup-for-linus-2' of ↵Linus Torvalds1-26/+38
git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc Pull ARM SoC late cleanups from Arnd Bergmann: "These are cleanups and smaller changes that either depend on earlier feature branches or came in late during the development cycle. We normally try to get all cleanups early, so these are the exceptions: - A follow-up on the clocksource reworks, hopefully the last time we need to merge clocksource subsystem changes through arm-soc. A first set of patches was part of the original 3.10 arm-soc cleanup series because of interdependencies with timer drivers now moved out of arch/arm. - Migrating the SPEAr13xx platform away from using auxdata for DMA channel descriptions towards using information in device tree, based on the earlier SPEAr multiplatform series - A few follow-ups on the Atmel SAMA5 support and other changes for Atmel at91 based on the larger at91 reworks. - Moving the armada irqchip implementation to drivers/irqchip - Several OMAP cleanups following up on the larger series already merged in 3.10." * tag 'cleanup-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (50 commits) ARM: OMAP4: change the device names in usb_bind_phy ARM: OMAP2+: Fix mismerge for timer.c between ff931c82 and da4a686a ARM: SPEAr: conditionalize SMP code ARM: arch_timer: Silence debug preempt warnings ARM: OMAP: remove unused variable serial: amba-pl011: fix !CONFIG_DMA_ENGINE case ata: arasan: remove the need for platform_data ARM: at91/sama5d34ek.dts: remove not needed compatibility string ARM: at91: dts: add MCI DMA support ARM: at91: dts: add i2c dma support ARM: at91: dts: set #dma-cells to the correct value ARM: at91: suspend both memory controllers on at91sam9263 irqchip: armada-370-xp: slightly cleanup irq controller driver irqchip: armada-370-xp: move IRQ handler to avoid forward declaration irqchip: move IRQ driver for Armada 370/XP ARM: mvebu: move L2 cache initialization in init_early() devtree: add binding documentation for sp804 ARM: integrator-cp: convert use CLKSRC_OF for timer init ARM: versatile: use OF init for sp804 timer ARM: versatile: add versatile dtbs to dtbs target ...
2013-04-20serial: amba-pl011: fix !CONFIG_DMA_ENGINE caseArnd Bergmann1-1/+1
I changed the prototype of the function earlier but only in the section for CONFIG_DMA_ENGINE, not the alternative. This makes the driver build again, e.g. for vexpress_defconfig. Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2013-04-17ARM: PL011: add support for extended FIFO-size of PL011-r1p5Jongsung Kim1-4/+16
The latest r1p5-revision of the ARM PL011 UART has 32-byte FIFOs, while all earlier ones have 16-byte FIFOs. This patch suggests a way to set the FIFO-size correctly & flexibly by using a member function named get_fifosize, rather than using the fifosize member variable. The function takes the UARTPeriphID, and returns the correct FIFO size. Signed-off-by: Jongsung Kim <neidhard.kim@lge.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-03amba-pl011: fix build error if CONFIG_DMA_ENGINE is not enabledChanho Min1-0/+4
Following patch will fix build error if CONFIG_DMA_ENGINE is unset. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Chanho Min <chanho.min@lge.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-29ARM: PL011: Add support for Rx DMA buffer polling.Chanho Min1-19/+138
In DMA support, The received data is not pushed to tty until the DMA buffer is filled. But some megabyte rate chips such as BT expect fast response and data should be pushed immediately. In order to fix this issue, We suggest the use of the timer for polling DMA buffer. In our test, no data loss occurred at high-baudrate as compared with interrupt- driven (We tested with 3Mbps). We changes: - We add timer for polling. If we set poll_timer to 10, every 10ms, timer handler checks the residue in the dma buffer and transfer data to the tty. Also, last_residue is updated for the next polling. - poll_timeout is used to prevent the timer's system cost. If poll_timeout is set to 3000 and no data is received in 3 seconds, we inactivate poll timer and driver falls back to interrupt-driven. When data is received again in FIFO and UART irq is occurred, we switch back to DMA mode and start polling. - We use consistent DMA mappings to avoid from the frequent cache operation of the timer function for default. - pl011_dma_rx_chars is modified. the pending size is recalculated because data can be taken by polling. - the polling time is adjusted if dma rx poll is enabled but no rate is specified. Ideal polling interval to push 1 character at every interval is the reciprocal of 'baud rate / 10 line bits per character / 1000 ms per sec'. But It is very aggressive to system. Experimentally, '10000000 / baud' is suitable to receive dozens of characters. the poll rate can be specified statically by dma_rx_poll_rate of the platform data as well. Changes compared to v1: - Use of consistent DMA mappings. - Added dma_rx_poll_rate in platform data to specify the polling interval. - Added dma_rx_poll_timeout in platform data to specify the polling timeout. Changes compared to v2: - Use of consistent DMA mappings for default. - Added dma_rx_poll_enable in platform data to adjust the polling time according to the baud rate. - remove unnecessary lock from the polling function. Signed-off-by: Chanho Min <chanho.min@lge.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-12serial: pl011: use generic DMA slave configuration if possibleArnd Bergmann1-25/+37
With the new OF DMA binding, it is possible to completely avoid the need for platform_data for configuring a DMA channel. In cases where the platform has already been converted, calling dma_request_slave_channel should get all the necessary information from the device tree. This also adds a binding document specific to the pl011 controller, and extends the generic primecell binding to mention "dmas" and other common properties. Like the patch that converts the dw_dma controller, this is completely untested and is looking for someone to try it out. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Grant Likely <grant.likely@secretlab.ca> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: devicetree-discuss@lists.ozlabs.org Cc: linux-arm-kernel@lists.infradead.org
2013-01-15TTY: switch tty_flip_buffer_pushJiri Slaby1-5/+2
Now, we start converting tty buffer functions to actually use tty_port. This will allow us to get rid of the need of tty in many call sites. Only tty_port will needed and hence no more tty_port_tty_get in those paths. Now, the one where most of tty_port_tty_get gets removed: tty_flip_buffer_push. IOW we also closed all the races in drivers not using tty_port_tty_get at all yet. Also we move tty_flip_buffer_push declaration from include/linux/tty.h to include/linux/tty_flip.h to all others while we are changing it anyway. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-15TTY: switch tty_insert_flip_stringJiri Slaby1-3/+3
Now, we start converting tty buffer functions to actually use tty_port. This will allow us to get rid of the need of tty in many call sites. Only tty_port will needed and hence no more tty_port_tty_get in those paths. tty_insert_flip_string this time. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-25serial/amba-pl011: use devm_* managed resourcesLinus Walleij1-16/+9
This switches a bunch of allocation and remapping to use the devm_* garbage collected methods and cleans up the error path and remove() paths consequently. devm_ioremap() is only in <linux/io.h> so fix up the erroneous <asm/*> include as well. Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Tested-by: Domenico Andreoli <domenico.andreoli@linux.com> Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-26tty/serial/amba-pl011: Quiesce interrupts in poll_get_charAnton Vorontsov1-0/+29
We need to quiesce interrupts in the poll_get_char routine, otherwise, if used with KGDB NMI debugger, we'll keep reentering the NMI. Quiescing interrupts is pretty straightforward, except for TXIM interrupt. The interrupt has "ready to transmit" meaning, so it's almost always raised, and the only way to silence it is to mask it. But that's OK, ops->start_tx will unmask it. Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Acked-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-26tty/serial/amba-pl011: Implement poll_init callbackAnton Vorontsov1-11/+33
The callback is used to initialize the hardware, nothing else should be done, i.e. we should not request interrupts (but we can and do unmask some of them, as they might be useful for NMI entry). As a side-effect, the patch also fixes a division by zero[1] when booting with kgdboc options specified (e.g. kgdboc=ttyAMA0,115200n8). The issue happens because serial core calls set_termios callback, but the driver doesn't know clock frequency, and thus cannot calculate proper baud rate values. [1] WARNING: at drivers/tty/serial/serial_core.c:400 uart_get_baud_rate+0xe8/0x14c() Modules linked in: [<c0018e50>] (unwind_backtrace+0x0/0xf0) from [<c0020ae8>] (warn_slowpath_common+0x4c/0x64) [<c0020ae8>] (warn_slowpath_common+0x4c/0x64) from [<c0020b1c>] (warn_slowpath_null+0x1c/0x24) [<c0020b1c>] (warn_slowpath_null+0x1c/0x24) from [<c0185ed8>] (uart_get_baud_rate+0xe8/0x14c) [<c0185ed8>] (uart_get_baud_rate+0xe8/0x14c) from [<c0187078>] (pl011_set_termios+0x48/0x278) [<c0187078>] (pl011_set_termios+0x48/0x278) from [<c01850b0>] (uart_set_options+0xe8/0x114) [<c01850b0>] (uart_set_options+0xe8/0x114) from [<c0185de4>] (uart_poll_init+0xd4/0xe0) [<c0185de4>] (uart_poll_init+0xd4/0xe0) from [<c016da8c>] (tty_find_polling_driver+0x100/0x17c) [<c016da8c>] (tty_find_polling_driver+0x100/0x17c) from [<c0188538>] (configure_kgdboc+0xc8/0x1b8) [<c0188538>] (configure_kgdboc+0xc8/0x1b8) from [<c00088a4>] (do_one_initcall+0x30/0x168) [<c00088a4>] (do_one_initcall+0x30/0x168) from [<c033784c>] (do_basic_setup+0x94/0xc8) [<c033784c>] (do_basic_setup+0x94/0xc8) from [<c03378e0>] (kernel_init+0x60/0xf4) [<c03378e0>] (kernel_init+0x60/0xf4) from [<c00144a0>] (kernel_thread_exit+0x0/0x8) ---[ end trace 7d41c9186f342c40 ]--- Division by zero in kernel. [<c0018e50>] (unwind_backtrace+0x0/0xf0) from [<c014546c>] (Ldiv0+0x8/0x10) [<c014546c>] (Ldiv0+0x8/0x10) from [<c0187098>] (pl011_set_termios+0x68/0x278) [<c0187098>] (pl011_set_termios+0x68/0x278) from [<c01850b0>] (uart_set_options+0xe8/0x114) [<c01850b0>] (uart_set_options+0xe8/0x114) from [<c0185de4>] (uart_poll_init+0xd4/0xe0) [<c0185de4>] (uart_poll_init+0xd4/0xe0) from [<c016da8c>] (tty_find_polling_driver+0x100/0x17c) [<c016da8c>] (tty_find_polling_driver+0x100/0x17c) from [<c0188538>] (configure_kgdboc+0xc8/0x1b8) [<c0188538>] (configure_kgdboc+0xc8/0x1b8) from [<c00088a4>] (do_one_initcall+0x30/0x168) [<c00088a4>] (do_one_initcall+0x30/0x168) from [<c033784c>] (do_basic_setup+0x94/0xc8) [<c033784c>] (do_basic_setup+0x94/0xc8) from [<c03378e0>] (kernel_init+0x60/0xf4) [<c03378e0>] (kernel_init+0x60/0xf4) from [<c00144a0>] (kernel_thread_exit+0x0/0x8) Division by zero in kernel. [<c0018e50>] (unwind_backtrace+0x0/0xf0) from [<c014546c>] (Ldiv0+0x8/0x10) [<c014546c>] (Ldiv0+0x8/0x10) from [<c0183a98>] (uart_update_timeout+0x4c/0x5c) [<c0183a98>] (uart_update_timeout+0x4c/0x5c) from [<c01870f8>] (pl011_set_termios+0xc8/0x278) [<c01870f8>] (pl011_set_termios+0xc8/0x278) from [<c01850b0>] (uart_set_options+0xe8/0x114) [<c01850b0>] (uart_set_options+0xe8/0x114) from [<c0185de4>] (uart_poll_init+0xd4/0xe0) [<c0185de4>] (uart_poll_init+0xd4/0xe0) from [<c016da8c>] (tty_find_polling_driver+0x100/0x17c) [<c016da8c>] (tty_find_polling_driver+0x100/0x17c) from [<c0188538>] (configure_kgdboc+0xc8/0x1b8) [<c0188538>] (configure_kgdboc+0xc8/0x1b8) from [<c00088a4>] (do_one_initcall+0x30/0x168) [<c00088a4>] (do_one_initcall+0x30/0x168) from [<c033784c>] (do_basic_setup+0x94/0xc8) [<c033784c>] (do_basic_setup+0x94/0xc8) from [<c03378e0>] (kernel_init+0x60/0xf4) [<c03378e0>] (kernel_init+0x60/0xf4) from [<c00144a0>] (kernel_thread_exit+0x0/0x8) Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Acked-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-26serial: pl011: handle corruption at high clock speedsLinus Walleij1-1/+14
This works around a few glitches in the ST version of the PL011 serial driver when using very high baud rates, as we do in the Ux500: 3, 3.25, 4 and 4.05 Mbps. Problem Observed/rootcause: When using high baud-rates, and the baudrate*8 is getting close to the provided clock frequency (so a division factor close to 1), when using bursts of characters (so they are abutted), then it seems as if there is not enough time to detect the beginning of the start-bit which is a timing reference for the entire character, and thus the sampling moment of character bits is moving towards the end of each bit, instead of the middle. Fix: Increase slightly the RX baud rate of the UART above the theoretical baudrate by 5%. This will definitely give more margin time to the UART_RX to correctly sample the data at the middle of the bit period. Also fix the ages old copy-paste error in the very stressed comment, it's referencing the registers used in the PL010 driver rather than the PL011 ones. Signed-off-by: Guillaume Jaunet <guillaume.jaunet@stericsson.com> Signed-off-by: Christophe Arnal <christophe.arnal@stericsson.com> Signed-off-by: Matthias Locher <matthias.locher@stericsson.com> Signed-off-by: Rajanikanth HV <rajanikanth.hv@stericsson.com> Cc: stable <stable@vger.kernel.org> Cc: Bibek Basu <bibek.basu@stericsson.com> Cc: Par-Gunnar Hjalmdahl <par-gunnar.hjalmdahl@stericsson.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-10serial: pl011: delete dangling bug flagLinus Walleij1-4/+0
The bug flag .interrupt_may_hang is not used since commit 4fd0690bb0c3955983560bb2767ee82e2b197f9b "serial: pl011: implement workaround for CTS clear event issue" so delete it. Cc: Rajanikanth H.V <rajanikanth.hv@stericsson.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Lee Jones <lee.jones@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-05serial: pl011: honour serial aliases in device treeMatthew Leach1-0/+36
If the order of UART nodes is changed in the device tree, then tty dev devices are attached to different serial ports causing the console to be directed to a different physical serial port. The "serial" aliases in the device tree should prevent this. This patch ensures that the UART driver creates tty devices that honour these aliases if a device tree is present. Acked-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Will Deacon <will.deacon@arm.com> Acked-by: Rob Herring <rob.herring@calxeda.com> Signed-off-by: Matthew Leach <matthew.leach@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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