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path: root/drivers/tty/serial/xilinx_uartps.c
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2018-09-18serial: uartps: Move register to probe based on run time detectionMichal Simek
Register uart driver in probe to be able to register one device with unique major/minor separately. Also calculate number of instances of this driver to be able to call uart_unregister_driver() when there is no instance. Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18serial: uartps: Move alias reading higher in probe()Michal Simek
This cosmetic change is done only for having next patch much easier to read. Moving id setup higher in probe is not affecting any usage of this driver and it also simplify error path. Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18serial: uartps: Do not use static struct uart_driver out of probe()Michal Simek
cdns_uart_suspend()/resume() and remove() are using static reference to struct uart_driver. Assign this reference to private data structure as preparation step for dynamic struct uart_driver allocation. Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18serial: uartps: Fix suspend functionalityNava kishore Manne
The driver's suspend/resume functions were buggy. If UART node contains any child node in the DT and the child is established a communication path with the parent UART. The relevant /dev/ttyPS* node will be not available for other operations. If the driver is trying to do any operations like suspend/resume without checking the tty->dev status it leads to the kernel crash/hang. This patch fix this issue by call the device_may_wake() with the generic parameter of type struct device. in the uart suspend and resume paths. It also fixes a race condition in the uart suspend path(i.e uart_suspend_port() should be called at the end of cdns_uart_suspend API this path updates the same) Signed-off-by: Nava kishore Manne <navam@xilinx.com> Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18serial: uartps: Do not initialize field to zero againMichal Simek
Writing zero and NULLs to already initialized fields is not needed. Remove this additional writes. Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-18serial: uartps: console_setup() can't be placed to init sectionMichal Simek
When console device is rebinded, console_setup() is called again. But marking it as __init means that function will be clear after boot is complete. If console device is binded again console_setup() is not found and error "Unable to handle kernel paging request at virtual address" is reported. Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-28serial: xuartps: remove unnecessary register writeHelmut Grohne
This writel writes the exact same value as the previous writel and is thus unnecessary. It accidentally became unnecessary in e3538c37ee38 ("tty: xuartps: Beautify read-modify writes"), but the new behaviour is now expected. Link: https://www.spinics.net/lists/linux-serial/msg23168.html Signed-off-by: Helmut Grohne <h.grohne@intenta.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-28serial: xuartps: reduce hardware TX race conditionHelmut Grohne
After sending data to the uart, the driver was waiting until the TX FIFO was empty (for every single char written). After that, TX was disabled by writing the original TX state to the status register. At that time however, the state machine could still be shifting characters. Not waiting can result in strange hardware states, especially when coupled with calls to cdns_uart_set_termios, whose symptom generally is garbage characters being received from uart or a hang. According to UG585, the TACTIVE bit of the channel status register indicates the shifter operation and we should be waiting for that bit to clear. Sending characters does not require the TX FIFO to be empty, but merely to not be full. So cdns_uart_console_putchar is updated accordingly. During tests with an instrumented kernel and an oscilloscope, we could determine that the chance of a race is reduced by this patch. It is not removed entirely. On the oscilloscope, one can see that disabling the transmitter early can result in the transmission hanging in the middle of a character for a tiny duration. This hiccup is enough to desynchronize with a remote device for a sequence of characters until a data bit doesn't match the start or stop bits anymore. Link: https://www.spinics.net/lists/linux-serial/msg23156.html Link: https://www.spinics.net/lists/linux-serial/msg26139.html Signed-off-by: Helmut Grohne <h.grohne@intenta.de> Acked-by: Sören Brinkmann <soren.brinkmann@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-28serial: xuartps: fix typo in cdns_uart_startupHelmut Grohne
The bit mask changes in commit 6e14f7c1f2c2 ("tty: xuartps: Improve startup function") doesn't do what the commit message advertises. The original behaviour was clearing the RX_DIS bit, but due to missing ~, that bit is now the only bit kept. Currently, the regression is harmless, because the previous write to the control register sets it to TXRST | RXRST. Thus the RX_DIS bit is previously cleared. The *RST bits are cleared by the hardware, so this commit does not currently change behaviour, but makes future changes less risky. Link: https://www.spinics.net/lists/linux-serial/msg23157.html Signed-off-by: Helmut Grohne <h.grohne@intenta.de> Fixes: 6e14f7c1f2c2 ("tty: xuartps: Improve startup function") Reviewed-by: Sören Brinkmann <soren.brinkmann@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-30Merge 4.17-rc3 into tty-nextGreg Kroah-Hartman
We want the tty and serial driver fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-25serial: uartps: Remove static port arrayMichal Simek
Allocate uart port structure dynamically. Signed-off-by: Michal Simek <michal.simek@xilinx.com> Reviewed-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-25serial: uartps: Move cnds_uart_get_port to probeMichal Simek
c&p this function to probe as preparation for removing cdns_uart_port[] static array. Signed-off-by: Michal Simek <michal.simek@xilinx.com> Reviewed-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-25serial: uartps: Use dynamic array for console portMichal Simek
Driver console functions are using pointer to static array with fixed size. There can be only one serial console at the time which is found by register_console(). register_console() is filling cons->index to port->line value. Signed-off-by: Michal Simek <michal.simek@xilinx.com> Reviewed-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-25serial: uartps: Remove console_initcall from the driverMichal Simek
register_console() is called from uart_add_one_port()->uart_configure_port() that's why register_console() is called twice. This patch remove console_initcall to call register_console() only from one location. Also based on my tests cdns_uart_console_setup() is not called from the first register_console() call. Signed-off-by: Michal Simek <michal.simek@xilinx.com> Reviewed-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-23tty: serial: xuartps: Setup early console when uartclk is also passedMichal Simek
Baudrate calculation depends on requested baudrate and uart clock. This patch is checking that uartclk is also passed. The same logic is used 8250_early.c/init_port function. Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-22tty: serial: simplify getting .drvdataWolfram Sang
We should get drvdata from struct device directly. Going via platform_device is an unneeded step back and forth. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Acked-by: Michal Simek <michal.simek@xilinx.com> Acked-by: Patrice Chotard <patrice.chotard@st.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28serial: xuartps: Fix out-of-bounds access through DT aliasGeert Uytterhoeven
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>
2017-11-08tty: serial: Remove redundant license textGreg Kroah-Hartman
Now that the SPDX tag is in all tty files, that identifies the license in a specific and legally-defined manner. So the extra GPL text wording can be removed as it is no longer needed at all. This is done on a quest to remove the 700+ different ways that files in the kernel describe the GPL license text. And there's unneeded stuff like the address (sometimes incorrect) for the FSF which is never needed. No copyright headers or other non-license-description text was removed. Cc: Jiri Slaby <jslaby@suse.com> Cc: Eric Anholt <eric@anholt.net> Cc: Stefan Wahren <stefan.wahren@i2se.com> Cc: Florian Fainelli <f.fainelli@gmail.com> Cc: Ray Jui <rjui@broadcom.com> Cc: Scott Branden <sbranden@broadcom.com> Cc: bcm-kernel-feedback-list@broadcom.com Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Helge Deller <deller@gmx.de> Cc: Joachim Eastwood <manabian@gmail.com> Cc: Matthias Brugger <matthias.bgg@gmail.com> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Tobias Klauser <tklauser@distanz.ch> Cc: Russell King <linux@armlinux.org.uk> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Richard Genoud <richard.genoud@gmail.com> Cc: Alexander Shiyan <shc_work@mail.ru> Cc: Baruch Siach <baruch@tkos.co.il> Cc: Pat Gefre <pfg@sgi.com> Cc: "Guilherme G. Piccoli" <gpiccoli@linux.vnet.ibm.com> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Vladimir Zapolskiy <vz@mleia.com> Cc: Sylvain Lemieux <slemieux.tyco@gmail.com> Cc: Carlo Caione <carlo@caione.org> Cc: Kevin Hilman <khilman@baylibre.com> Cc: Liviu Dudau <liviu.dudau@arm.com> Cc: Sudeep Holla <sudeep.holla@arm.com> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: Andy Gross <andy.gross@linaro.org> Cc: David Brown <david.brown@linaro.org> Cc: "Andreas Färber" <afaerber@suse.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Kevin Cernekee <cernekee@gmail.com> Cc: Laxman Dewangan <ldewangan@nvidia.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Jonathan Hunter <jonathanh@nvidia.com> Cc: Barry Song <baohua@kernel.org> Cc: Patrice Chotard <patrice.chotard@st.com> Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com> Cc: Alexandre Torgue <alexandre.torgue@st.com> Cc: Chris Metcalf <cmetcalf@mellanox.com> Cc: Peter Korsgaard <jacmet@sunsite.dk> Cc: Timur Tabi <timur@tabi.org> Cc: Tony Prisk <linux@prisktech.co.nz> Cc: Michal Simek <michal.simek@xilinx.com> Cc: "Sören Brinkmann" <soren.brinkmann@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-08tty: add SPDX identifiers to all remaining files in drivers/tty/Greg Kroah-Hartman
It's good to have SPDX identifiers in all files to make it easier to audit the kernel tree for correct licenses. Update the drivers/tty files files with the correct SPDX license identifier based on the license text in the file itself. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This work is based on a script and data from Thomas Gleixner, Philippe Ombredanne, and Kate Stewart. Cc: Jiri Slaby <jslaby@suse.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Chris Metcalf <cmetcalf@mellanox.com> Cc: Jiri Kosina <jikos@kernel.org> Cc: David Sterba <dsterba@suse.com> Cc: James Hogan <jhogan@kernel.org> Cc: Rob Herring <robh@kernel.org> Cc: Eric Anholt <eric@anholt.net> Cc: Stefan Wahren <stefan.wahren@i2se.com> Cc: Florian Fainelli <f.fainelli@gmail.com> Cc: Ray Jui <rjui@broadcom.com> Cc: Scott Branden <sbranden@broadcom.com> Cc: bcm-kernel-feedback-list@broadcom.com Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Helge Deller <deller@gmx.de> Cc: Joachim Eastwood <manabian@gmail.com> Cc: Matthias Brugger <matthias.bgg@gmail.com> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Tobias Klauser <tklauser@distanz.ch> Cc: Russell King <linux@armlinux.org.uk> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Richard Genoud <richard.genoud@gmail.com> Cc: Alexander Shiyan <shc_work@mail.ru> Cc: Baruch Siach <baruch@tkos.co.il> Cc: "Maciej W. Rozycki" <macro@linux-mips.org> Cc: "Uwe Kleine-König" <kernel@pengutronix.de> Cc: Pat Gefre <pfg@sgi.com> Cc: "Guilherme G. Piccoli" <gpiccoli@linux.vnet.ibm.com> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Vladimir Zapolskiy <vz@mleia.com> Cc: Sylvain Lemieux <slemieux.tyco@gmail.com> Cc: Carlo Caione <carlo@caione.org> Cc: Kevin Hilman <khilman@baylibre.com> Cc: Liviu Dudau <liviu.dudau@arm.com> Cc: Sudeep Holla <sudeep.holla@arm.com> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: Andy Gross <andy.gross@linaro.org> Cc: David Brown <david.brown@linaro.org> Cc: "Andreas Färber" <afaerber@suse.de> Cc: Kevin Cernekee <cernekee@gmail.com> Cc: Laxman Dewangan <ldewangan@nvidia.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Jonathan Hunter <jonathanh@nvidia.com> Cc: Barry Song <baohua@kernel.org> Cc: Patrice Chotard <patrice.chotard@st.com> Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com> Cc: Alexandre Torgue <alexandre.torgue@st.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Peter Korsgaard <jacmet@sunsite.dk> Cc: Timur Tabi <timur@tabi.org> Cc: Tony Prisk <linux@prisktech.co.nz> Cc: Michal Simek <michal.simek@xilinx.com> Cc: "Sören Brinkmann" <soren.brinkmann@xilinx.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Kate Stewart <kstewart@linuxfoundation.org> Cc: Philippe Ombredanne <pombredanne@nexb.com> Cc: Jiri Slaby <jslaby@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-04tty: xilinx_uartps: move to arch_initcall for earlier consoleShubhrajyoti Datta
move to arch_initcall to get the console up really early, it is quite helpful for spotting early boot problems. Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Tested-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-30serial: xuartps: Remove __init marking from early writeJeffy Chen
The earlycon would be alive outside the init code in these cases: 1/ we have keep_bootcon in cmdline. 2/ we don't have a real console to switch to. So remove the __init marking to avoid invalid memory access. Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com> Reviewed-by: Douglas Anderson <dianders@chromium.org> Tested-by: Brian Norris <briannorris@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-03serial: uartps: Fix kernel doc warningsNava kishore Manne
This patch fixes the kernel doc warnings in the driver. Signed-off-by: Nava kishore Manne <navam@xilinx.com> Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18serial: xilinx_uartps: Fix the error pathShubhrajyoti Datta
Fix the runtime calls in the error path. Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-08serial: xuartps: Enable clocks in the pm disable case alsoShubhrajyoti Datta
When Power management is disabled then the clocks are not getting enabled. This patch enables it for the !PM case also. While at it also pm_runtime_set_active is called before calling pm_runtime_enable. Reported-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-17serial: xuartps: Cleanup the clock enableShubhrajyoti Datta
The core handles the clocking now. Remove the clock disable in suspend. In resume we enable the clocks and disable after register write. Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-14serial: xilinx_uartps: Add pm runtime supportShubhrajyoti Datta
Adds pm runtime support to xilinx uart ps. Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-25serial: xuartps: Enable uart loopback modeYasir-Khan
This patch adds xilinx uart loopback support by modifying the cdns_uart_set_mctrl function to handle the switch to loopback mode. After this patch, the loopback mode can be enabled/disabled by setting/clearing the TIOCM_LOOP modem bit via TIOCMBIS/TIOCMBIC ioctls respectively. Signed-off-by: Yasir-Khan <yasir_khan@mentor.com> Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-27serial: xuartps: Add new compatible string for ZynqMPNava kishore Manne
This patch Adds the new compatible string for ZynqMP SoC. Signed-off-by: Nava kishore Manne <navam@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-27serial: xuartps: Add some register initialisation to cdns_early_console_setup()Scott Telford
Add initialisation of control register and baud rate to cdns_early_console_setup(), required when running kernel standalone without a boot loader. Baud rate is only initialised when specified in earlycon command-line option, otherwise it is assumed this has been set by a boot loader. Updated Documentation/kernel-parameters.txt accordingly. Signed-off-by: Scott Telford <stelford@cadence.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-27serial: xuartps: Removed unwanted checks while reading the error conditionsNava kishore Manne
This patch Remove the unwated checks while reading the parity,framing, overrun and Break detection errors. Signed-off-by: Nava kishore Manne <navam@xilinx.com> Signed-off-by: Michal Simek <michal.simek@xilinx.com> [stelford@cadence.com: cherry picked from https://github.com/Xilinx/linux-xlnx commit b1cf74970df5470ffbc8e7876a9edf5e3498ef94] Signed-off-by: Scott Telford <stelford@cadence.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-27serial: xuartps: Rewrite the interrupt handling logicAnirudha Sarangi
The existing interrupt handling logic has following issues. - Upon a parity error with default configuration, the control never comes out of the ISR thereby hanging Linux. - The error handling logic around framing and parity error are buggy. There are chances that the errors will never be captured. This patch ensures that the status registers are cleared on all cases so that a hang situation never arises. Signed-off-by: Anirudha Sarangi <anirudh@xilinx.com> Signed-off-by: Michal Simek <michal.simek@xilinx.com> [stelford@cadence.com: cherry picked from https://github.com/Xilinx/linux-xlnx commit ac297e20d399850d7a8e373b6eccf2e183c15165 with manual conflict resolution] Signed-off-by: Scott Telford <stelford@cadence.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-22serial: xuartps: Do not enable parity error interruptAnirudha Sarangi
The patch makes changes not to enable parity error interrupt. With the current implementation, each parity error results in two distinct interrupts (almost always). The first one is normal parity error interrupt with no data in the fifo and the second one is a proper Rx interrupt with the received data in the fifo. By disabling parity error interrupt we still ensure handling of parity errors as for the Rx fifo interrupt the parity error still shows up in the interrupt status register. Considering the fact that the by default INPCK and IGNPAR are not set, this is the optimal implementation for parity error handling. Signed-off-by: Anirudha Sarangi <anirudh@xilinx.com> Signed-off-by: Michal Simek <michal.simek@xilinx.com> [stelford@cadence.com: cherry picked from https://github.com/Xilinx/linux-xlnx commit bf9f610b445e2c9ed33c41e1e0e30b43be4e1f97 with manual conflict resolution] Signed-off-by: Scott Telford <stelford@cadence.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-22tty: serial: xuartps: Wait for rx and tx reset done statusNava kishore Manne
After issuing the reset, driver is not checking the rx and tx reset done status. So, modified driver to wait for the reset done status. Signed-off-by: Nava kishore Manne <navam@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-22serial: xuartps: Adds RXBS register support for zynqmpNava kishore Manne
This patch adds RXBS register access support for zynqmp. To avoid the corner error conditions it will consider only RXBS[2:0] bits while checking the error conditions (Parity,Framing and BRAK). Signed-off-by: Nava kishore Manne <navam@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-02tty: xuartps: constify uart_ops structuresJulia Lawall
Check for uart_ops structures that are only stored in the ops field of a uart_port structure. This field is declared const, so uart_ops structures that have this property can be declared as const also. The semantic patch that makes this change is as follows: (http://coccinelle.lip6.fr/) // <smpl> @r disable optional_qualifier@ identifier i; position p; @@ static struct uart_ops i@p = { ... }; @ok@ identifier r.i; struct uart_port e; position p; @@ e.ops = &i@p; @bad@ position p != {r.p,ok.p}; identifier r.i; struct uart_ops e; @@ e@i@p @depends on !bad disable optional_qualifier@ identifier r.i; @@ static +const struct uart_ops i = { ... }; // </smpl> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-25tty: xuartps: disable clocks when not usedShubhrajyoti Datta
Currently the clocks are enabled at probe and disabled at remove. Instead enable the clocks when used. Signed-off-by: Shubhrajyoti Datta <shubhraj@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-07serial: xuartps: Enable OF earlycon supportMichal Simek
Support early console setup via DT for all listed compatible strings. Remove EARLYCON_DECLARE which was done by: "Use common framework for earlycon declarations" (sha1: 2eaa790989e03900298ad24f77f1086dbbc1aebd) when OF_EARLYCON_DECLARE is defined. Signed-off-by: Michal Simek <michal.simek@xilinx.com> Reviewed-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-06tty: xuartps: Consolidate TX handlingSoren Brinkmann
start_tx and the ISR used largely identical code to transmit data. Consolidate that in one place. Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-06tty: xuartps: Remove '_OFFSET' suffix from #definesSoren Brinkmann
Remove the _OFFSET suffix from all register defines which makes code a little easier to read and avoids a few line breaks. Suggested-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-06tty: xuartps: Improve sysrq handlingSoren Brinkmann
Handling magic sysrq included dropping a lock to avoid a deadlock that happened when cdns_uart_console_write tried to acquire a lock in the from the sysrq code path. By making the acquisition of the lock in cdns_uart_console_write depending on port->sysrq, cdns_uart_handle_rx can be simplified to simply call uart_handle_sysrq. Suggested-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-06tty: xuartps: Cleanup: Reformat if-elseSoren Brinkmann
Convert an if-else into the more common early return on error, reducing the indent level of the happy path. Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-06tty: xuartps: Refactor IRQ handlingSoren Brinkmann
The system could deadlock handling RX IRQs when RX-related IRQ conditions became true while the receiver was disabled. To avoid this, enable/disable the RX/TX IRQs together with the receiver/transmitter. Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-06tty: xuartps: Move request_irq to after setting up the HWSoren Brinkmann
Request_irq() should be _after_ h/w programming, otherwise an interrupt could be triggered and in-progress before the h/w has been setup. Reported-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-06tty: xuartps: Move RX path into helper functionSoren Brinkmann
Move RX-related IRQ handling into a helper function. Fixes a problem where every char received after a parity or frame error in the current isr will also be tagged as a parity or frame error. Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com> Reviewed-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-06tty: xuartps: Acquire port lock for shutdownSoren Brinkmann
Shutting down the UART port can happen while console operations are in progress. Holding the port lock serializes these operations and avoids the UART HW to be disabled in the middle of console prints. Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com> Reviewed-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-06tty: xuartps: Keep lock for whole ISRSoren Brinkmann
The RX path in the interrupt handler released a lock unnecessarily. Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com> Reviewed-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-06tty: xuartps: Improve startup functionSoren Brinkmann
The startup function is supposed to initialize the UART for receiving. Hence, don't enable the TX part. Also, protect HW accesses with the port lock. Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com> Reviewed-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-06tty: xuartps: Clear interrupt status register in shutdownSoren Brinkmann
When shutting down the UART, clear the interrupt status register. Bits in the ISR are cleared by writing them as '1'. Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com> Reviewed-by: Peter Hurley <peter@hurleysoftware.com> Reviewed-by: Moritz Fischer <moritz.fischer@ettus.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-06tty: xuartps: Don't consider circular buffer when enabling transmitterSoren Brinkmann
Restarting the transmitter even if the circ buffer is empty may be necessary to push out remaining data when the port is restarted after being stopped. Cc: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com> Reviewed-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-06tty: xuartps: Use spinlock to serialize HW accessSoren Brinkmann
Instead of disabling the IRQ, use the spin lock to serialize accesses to the HW. This protects the driver from interference of non-IRQ callbacks with each other and makes the driver more consistent in its serialization method. Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com> Reviewed-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>