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path: root/drivers/tty/serial/amba-pl011.c
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2024-04-09serial: amba-pl011: move variable into CONFIG_DMA_ENGINE conditionalLino Sanfilippo1-1/+1
Variable dmacr is only used if DMA is enabled, so move it into the CONFIG_DMA_ENGINE conditional. Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com> Link: https://lore.kernel.org/r/20240407002709.16224-3-l.sanfilippo@kunbus.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-09serial: amba-pl011: get rid of useless wrapper pl011_get_rs485_mode()Lino Sanfilippo1-13/+1
Due to earlier code changes function pl011_get_rs485_mode() is now merely a wrapper for uart_get_rs485_mode() which does not add any further functionality. So remove it and instead call uart_get_rs485_mode() directly. Reviewed-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com> Link: https://lore.kernel.org/r/20240407002709.16224-2-l.sanfilippo@kunbus.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-09tty: serial: switch from circ_buf to kfifoJiri Slaby (SUSE)1-27/+19
Switch from struct circ_buf to proper kfifo. kfifo provides much better API, esp. when wrap-around of the buffer needs to be taken into account. Look at pl011_dma_tx_refill() or cpm_uart_tx_pump() changes for example. Kfifo API can also fill in scatter-gather DMA structures, so it easier for that use case too. Look at lpuart_dma_tx() for example. Note that not all drivers can be converted to that (like atmel_serial), they handle DMA specially. Note that usb-serial uses kfifo for TX for ages. omap needed a bit more care as it needs to put a char into FIFO to start the DMA transfer when OMAP_DMA_TX_KICK is set. In that case, we have to do kfifo_dma_out_prepare twice: once to find out the tx_size (to find out if it is worths to do DMA at all -- size >= 4), the second time for the actual transfer. All traces of circ_buf are removed from serial_core.h (and its struct uart_state). Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org> Cc: Al Cooper <alcooperx@gmail.com> Cc: Matthias Brugger <matthias.bgg@gmail.com> Cc: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> Cc: Kumaravel Thiagarajan <kumaravel.thiagarajan@microchip.com> Cc: Tharun Kumar P <tharunkumar.pasumarthi@microchip.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Vineet Gupta <vgupta@kernel.org> Cc: Richard Genoud <richard.genoud@gmail.com> Cc: Nicolas Ferre <nicolas.ferre@microchip.com> Cc: Alexandre Belloni <alexandre.belloni@bootlin.com> Cc: Claudiu Beznea <claudiu.beznea@tuxon.dev> Cc: Alexander Shiyan <shc_work@mail.ru> Cc: Baruch Siach <baruch@tkos.co.il> Cc: Maciej W. Rozycki <macro@orcam.me.uk> Cc: Shawn Guo <shawnguo@kernel.org> Cc: Sascha Hauer <s.hauer@pengutronix.de> Cc: Fabio Estevam <festevam@gmail.com> Cc: Neil Armstrong <neil.armstrong@linaro.org> Cc: Kevin Hilman <khilman@baylibre.com> Cc: Jerome Brunet <jbrunet@baylibre.com> Cc: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Cc: Taichi Sugaya <sugaya.taichi@socionext.com> Cc: Takao Orito <orito.takao@socionext.com> Cc: Bjorn Andersson <andersson@kernel.org> Cc: Konrad Dybcio <konrad.dybcio@linaro.org> Cc: Pali Rohár <pali@kernel.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Aneesh Kumar K.V <aneesh.kumar@kernel.org> Cc: Naveen N. Rao <naveen.n.rao@linux.ibm.com> Cc: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> Cc: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> Cc: Alim Akhtar <alim.akhtar@samsung.com> Cc: Laxman Dewangan <ldewangan@nvidia.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Jonathan Hunter <jonathanh@nvidia.com> Cc: Orson Zhai <orsonzhai@gmail.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Chunyan Zhang <zhang.lyra@gmail.com> Cc: Patrice Chotard <patrice.chotard@foss.st.com> Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com> Cc: Alexandre Torgue <alexandre.torgue@foss.st.com> Cc: David S. Miller <davem@davemloft.net> Cc: Hammer Hsieh <hammerh0314@gmail.com> Cc: Peter Korsgaard <jacmet@sunsite.dk> Cc: Timur Tabi <timur@kernel.org> Cc: Michal Simek <michal.simek@amd.com> Cc: Sumit Semwal <sumit.semwal@linaro.org> Cc: Christian König <christian.koenig@amd.com> Link: https://lore.kernel.org/r/20240405060826.2521-13-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-03serial: amba-pl011: Use uart_prepare_sysrq_char().Sebastian Andrzej Siewior1-16/+8
The port lock is a spinlock_t which is becomes a sleeping lock on PREEMPT_RT. The driver splits the locking function into two parts: local_irq_save() and uart_port_lock() and this breaks PREEMPT_RT. Delay handling sysrq until port lock is dropped. Remove the special case in the console write routine an always use the complete locking function. Cc: Russell King <linux@armlinux.org.uk> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Link: https://lore.kernel.org/r/20240301215246.891055-2-bigeasy@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-19serial: amba-pl011: Fix DMA transmission in RS485 modeLino Sanfilippo1-30/+30
When DMA is used in RS485 mode make sure that the UARTs tx section is enabled before the DMA buffers are queued for transmission. Cc: stable@vger.kernel.org Fixes: 8d479237727c ("serial: amba-pl011: add RS485 support") Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com> Link: https://lore.kernel.org/r/20240216224709.9928-2-l.sanfilippo@kunbus.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-12-15tty: serial: amba-pl011: factor QDF2400 SoC erratum 44 out of probeThéo Lebrun1-7/+18
On this platform, different vendor data is used. That requires a compile-time check as we access (1) a global boolean & (2) our local vendor data. Both symbols are accessible only when CONFIG_ACPI_SPCR_TABLE is enabled. Factor the vendor data overriding to a separate function that is empty when CONFIG_ACPI_SPCR_TABLE is not defined. Suggested-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com> Link: https://lore.kernel.org/r/20231207-mbly-uart-v6-8-e384afa5e78c@bootlin.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-12-15tty: serial: amba-pl011: unindent pl011_console_get_options function bodyThéo Lebrun1-22/+21
The whole function body is encapsulated inside an if-condition. Reverse the if logic and early return to remove one indentation level. Also turn two nested ifs into a single one at the end of the function. Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com> Link: https://lore.kernel.org/r/20231207-mbly-uart-v6-7-e384afa5e78c@bootlin.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-12-15tty: serial: amba-pl011: fix miscellaneous checkpatch warningsThéo Lebrun1-7/+6
Fix the following messages from checkpatch: $ ./scripts/checkpatch.pl --strict --file \ drivers/tty/serial/amba-pl011.c ERROR: do not initialise statics to false WARNING: Possible unnecessary 'out of memory' message WARNING: Prefer 'unsigned int' to bare use of 'unsigned' WARNING: Prefer [subsystem eg: netdev]_info([subsystem]dev, ... then dev_info(dev, ... then pr_info(... to CHECK: Prefer using the BIT macro Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com> Link: https://lore.kernel.org/r/20231207-mbly-uart-v6-6-e384afa5e78c@bootlin.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-12-15tty: serial: amba-pl011: fix formatting of conditionsThéo Lebrun1-12/+14
Fix the following checkpatch warnings & checks: $ ./scripts/checkpatch.pl --strict --file \ drivers/tty/serial/amba-pl011.c CHECK: Unbalanced braces around else statement CHECK: Unnecessary parentheses around '[...]' CHECK: braces {} should be used on all arms of this statement CHECK: Comparison to NULL could be written "[...]" WARNING: Comparisons should place the constant on the right side of the test Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com> Link: https://lore.kernel.org/r/20231207-mbly-uart-v6-5-e384afa5e78c@bootlin.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-12-15tty: serial: amba-pl011: avoid quoted string split across linesThéo Lebrun1-8/+8
Remove all instances of quoted strings split across lines. Fix four checkpatch warnings: $ ./scripts/checkpatch.pl --strict --file \ drivers/tty/serial/amba-pl011.c WARNING: quoted string split across lines [...] Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com> Link: https://lore.kernel.org/r/20231207-mbly-uart-v6-4-e384afa5e78c@bootlin.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-12-15tty: serial: amba-pl011: replace TIOCMBIT macros by static functionsThéo Lebrun1-21/+24
The driver uses two TIOCMBIT macros inside pl011_{get,set}_mctrl to simplify the logic. Those look scary to checkpatch because they contain ifs without do-while loops. Avoid the macros by creating small equivalent static functions; that lets the compiler do its type checking & avoids checkpatch errors. For the second instance __assign_bit is not usable because it deals with unsigned long pointers whereas we have an unsigned int in pl011_set_mctrl. This addresses the following checkpatch warnings: $ ./scripts/checkpatch.pl --strict --file \ drivers/tty/serial/amba-pl011.c ERROR: Macros starting with if should be enclosed by a do - while loop to avoid possible if/else logic defects CHECK: Macro argument 'uartbit' may be better as '(uartbit)' to avoid precedence issues ERROR: Macros starting with if should be enclosed by a do - while loop to avoid possible if/else logic defects CHECK: Macro argument 'tiocmbit' may be better as '(tiocmbit)' to avoid precedence issues Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com> Link: https://lore.kernel.org/r/20231207-mbly-uart-v6-3-e384afa5e78c@bootlin.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-12-15tty: serial: amba-pl011: fix whitespace formattingThéo Lebrun1-52/+45
Follow recommandations from: $ ./scripts/checkpatch.pl --strict --file \ drivers/tty/serial/amba-pl011.c We fix 5 warnings and 48 checks, all related to whitespace. Culprits are: CHECK: Alignment should match open parenthesis CHECK: Blank lines aren't necessary after an open brace '{' CHECK: Lines should not end with a '(' CHECK: Please don't use multiple blank lines CHECK: Please use a blank line after function/struct/union/enum declarations CHECK: spaces preferred around that '/' (ctx:VxV) CHECK: spaces preferred around that '|' (ctx:VxV) WARNING: Missing a blank line after declarations WARNING: please, no spaces at the start of a line Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com> Link: https://lore.kernel.org/r/20231207-mbly-uart-v6-2-e384afa5e78c@bootlin.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-12-11Merge 6.7-rc5 into tty-nextGreg Kroah-Hartman1-58/+54
We need the serial fixes in here as well to build off of. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-23ARM: PL011: Fix DMA supportArnd Bergmann1-58/+54
Since there is no guarantee that the memory returned by dma_alloc_coherent() is associated with a 'struct page', using the architecture specific phys_to_page() is wrong, but using virt_to_page() would be as well. Stop using sg lists altogether and just use the *_single() functions instead. This also simplifies the code a bit since the scatterlists in this driver always have only one entry anyway. https://lore.kernel.org/lkml/86db0fe5-930d-4cbb-bd7d-03367da38951@app.fastmail.com/ Use consistent names for dma buffers gc: Add a commit log from the initial thread: https://lore.kernel.org/lkml/86db0fe5-930d-4cbb-bd7d-03367da38951@app.fastmail.com/ Use consistent names for dma buffers Fixes: cb06ff102e2d7 ("ARM: PL011: Add support for Rx DMA buffer polling.") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Tested-by: Gregory CLEMENT <gregory.clement@bootlin.com> Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com> Cc: stable <stable@kernel.org> Link: https://lore.kernel.org/r/20231122171503.235649-1-gregory.clement@bootlin.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-23serial: amba-pl011: convert not to use dma_request_slave_channel()Christophe JAILLET1-3/+3
dma_request_slave_channel() is deprecated. dma_request_chan() should be used directly instead. Switch to the preferred function and update the error handling accordingly. Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Link: https://lore.kernel.org/r/6f76e22f77d776d6c1f176d56e7ee341314d8554.1700405529.git.christophe.jaillet@wanadoo.fr Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-23serial: amba-pl011: Convert to platform remove callback returning voidUwe Kleine-König1-3/+2
The .remove() callback for a platform driver returns an int which makes many driver authors wrongly assume it's possible to do error handling by returning an error code. However the value returned is ignored (apart from emitting a warning) and this typically results in resource leaks. To improve here there is a quest to make the remove callback return void. In the first step of this quest all drivers are converted to .remove_new(), which already returns void. Eventually after all drivers are converted, .remove_new() will be renamed to .remove(). Trivially convert this driver from always returning zero in the remove callback to the void returning variant. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Link: https://lore.kernel.org/r/20231110152927.70601-7-u.kleine-koenig@pengutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-03serial: amba-pl011: Do not complain when DMA is absentFabio Estevam1-1/+1
Many SoCs do not integrate DMA for the amba pl011 UART, causing the following message on boot: uart-pl011 80074000.serial: no DMA platform data The UART still works in PIO, so better not to print such message that may confuse people by causing them to think that there is something wrong with the UART. Change the message to debug level. Signed-off-by: Fabio Estevam <festevam@denx.de> Link: https://lore.kernel.org/r/20230928145842.466933-1-festevam@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-09-18serial: amba-pl011: Use port lock wrappersThomas Gleixner1-36/+36
When a serial port is used for kernel console output, then all modifications to the UART registers which are done from other contexts, e.g. getty, termios, are interference points for the kernel console. So far this has been ignored and the printk output is based on the principle of hope. The rework of the console infrastructure which aims to support threaded and atomic consoles, requires to mark sections which modify the UART registers as unsafe. This allows the atomic write function to make informed decisions and eventually to restore operational state. It also allows to prevent the regular UART code from modifying UART registers while printk output is in progress. All modifications of UART registers are guarded by the UART port lock, which provides an obvious synchronization point with the console infrastructure. To avoid adding this functionality to all UART drivers, wrap the spin_[un]lock*() invocations for uart_port::lock into helper functions which just contain the spin_[un]lock*() invocations for now. In a subsequent step these helpers will gain the console synchronization mechanisms. Converted with coccinelle. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Ogness <john.ogness@linutronix.de> Link: https://lore.kernel.org/r/20230914183831.587273-18-john.ogness@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-25tty: Explicitly include correct DT includesRob Herring1-1/+1
The DT of_device.h and of_platform.h date back to the separate of_platform_bus_type before it as merged into the regular platform bus. As part of that merge prepping Arm DT support 13 years ago, they "temporarily" include each other. They also include platform_device.h and of.h. As a result, there's a pretty much random mix of those include files used throughout the tree. In order to detangle these headers and replace the implicit includes with struct declarations, users need to explicitly include the correct includes. Signed-off-by: Rob Herring <robh@kernel.org> Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> # for imx Link: https://lore.kernel.org/r/20230724205440.767071-1-robh@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-25serial: drivers: switch ch and flag to u8Jiri Slaby1-1/+2
Now that the serial layer explicitly expects 'u8' for flags and characters, propagate this type to drivers' (RX) routines. Note that amba-pl011's, clps711x's and st-asc's 'ch' are left unchanged because 'ch' contains not only a character, but whole status. Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org> Cc: Tobias Klauser <tklauser@distanz.ch> Cc: Russell King <linux@armlinux.org.uk> Cc: Vineet Gupta <vgupta@kernel.org> Cc: Richard Genoud <richard.genoud@gmail.com> Cc: Nicolas Ferre <nicolas.ferre@microchip.com> Cc: Alexandre Belloni <alexandre.belloni@bootlin.com> Cc: Claudiu Beznea <claudiu.beznea@microchip.com> Cc: Alexander Shiyan <shc_work@mail.ru> Cc: Baruch Siach <baruch@tkos.co.il> Cc: "Maciej W. Rozycki" <macro@orcam.me.uk> Cc: Taichi Sugaya <sugaya.taichi@socionext.com> Cc: Takao Orito <orito.takao@socionext.com> Cc: Shawn Guo <shawnguo@kernel.org> Cc: Sascha Hauer <s.hauer@pengutronix.de> Cc: Pengutronix Kernel Team <kernel@pengutronix.de> Cc: Fabio Estevam <festevam@gmail.com> Cc: NXP Linux Team <linux-imx@nxp.com> Cc: Kevin Cernekee <cernekee@gmail.com> Cc: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> Cc: Alim Akhtar <alim.akhtar@samsung.com> Cc: Laxman Dewangan <ldewangan@nvidia.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Jonathan Hunter <jonathanh@nvidia.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Orson Zhai <orsonzhai@gmail.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Chunyan Zhang <zhang.lyra@gmail.com> Cc: Patrice Chotard <patrice.chotard@foss.st.com> Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com> Cc: Alexandre Torgue <alexandre.torgue@foss.st.com> Cc: Hammer Hsieh <hammerh0314@gmail.com> Acked-by: Richard GENOUD <richard.genoud@gmail.com> Acked-by: Tobias Klauser <tklauser@distanz.ch> Acked-by: Thierry Reding <treding@nvidia.com> Acked-by: Maciej W. Rozycki <macro@orcam.me.uk> Link: https://lore.kernel.org/r/20230712081811.29004-11-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-13serial: pl011: set UART011_CR_RXE in pl011_set_termios after port shutdownHongyu Xie1-0/+7
UART011_CR_RXE is set in pl011_startup() during normal initialization, and cleared by pl011_disable_uart() during port shutdown. You can use a none-console port in poll mode like kgdboc does with tty_find_polling_driver() after a port shutdown. But pl011_startup() is not called in tty_find_polling_driver(). So you need to set UART011_CR_RXE to reenable receive function. Not sure setting UART011_CR_RXE in pl011_set_termios() is a good idea through. Signed-off-by: Hongyu Xie <xiehongyu1@kylinos.cn> Link: https://lore.kernel.org/r/20230501070909.1144547-1-xiehongyu1@kylinos.cn Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19serial: amba-pl011: fix high priority character transmission in rs486 modeLino Sanfilippo1-4/+4
In RS485 mode the transmission of a high priority character fails since it is written to the data register before the transmitter is enabled. Fix this in pl011_tx_chars() by enabling RS485 transmission before writing the character. Fixes: 8d479237727c ("serial: amba-pl011: add RS485 support") Cc: stable@vger.kernel.org Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com> Link: https://lore.kernel.org/r/20230108181735.10937-1-LinoSanfilippo@gmx.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-22serial: pl011: Do not clear RX FIFO & RX interrupt in unthrottle.delisun1-1/+10
Clearing the RX FIFO will cause data loss. Copy the pl011_enabl_interrupts implementation, and remove the clear interrupt and FIFO part of the code. Fixes: 211565b10099 ("serial: pl011: UPSTAT_AUTORTS requires .throttle/unthrottle") Signed-off-by: delisun <delisun@pateo.com.cn> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20221110020108.7700-1-delisun@pateo.com.cn Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-22serial: amba-pl011: avoid SBSA UART accessing DMACR registerJiamei Xie1-0/+3
Chapter "B Generic UART" in "ARM Server Base System Architecture" [1] documentation describes a generic UART interface. Such generic UART does not support DMA. In current code, sbsa_uart_pops and amba_pl011_pops share the same stop_rx operation, which will invoke pl011_dma_rx_stop, leading to an access of the DMACR register. This commit adds a using_rx_dma check in pl011_dma_rx_stop to avoid the access to DMACR register for SBSA UARTs which does not support DMA. When the kernel enables DMA engine with "CONFIG_DMA_ENGINE=y", Linux SBSA PL011 driver will access PL011 DMACR register in some functions. For most real SBSA Pl011 hardware implementations, the DMACR write behaviour will be ignored. So these DMACR operations will not cause obvious problems. But for some virtual SBSA PL011 hardware, like Xen virtual SBSA PL011 (vpl011) device, the behaviour might be different. Xen vpl011 emulation will inject a data abort to guest, when guest is accessing an unimplemented UART register. As Xen VPL011 is SBSA compatible, it will not implement DMACR register. So when Linux SBSA PL011 driver access DMACR register, it will get an unhandled data abort fault and the application will get a segmentation fault: Unhandled fault at 0xffffffc00944d048 Mem abort info: ESR = 0x96000000 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 FSC = 0x00: ttbr address size fault Data abort info: ISV = 0, ISS = 0x00000000 CM = 0, WnR = 0 swapper pgtable: 4k pages, 39-bit VAs, pgdp=0000000020e2e000 [ffffffc00944d048] pgd=100000003ffff803, p4d=100000003ffff803, pud=100000003ffff803, pmd=100000003fffa803, pte=006800009c090f13 Internal error: ttbr address size fault: 96000000 [#1] PREEMPT SMP ... Call trace: pl011_stop_rx+0x70/0x80 tty_port_shutdown+0x7c/0xb4 tty_port_close+0x60/0xcc uart_close+0x34/0x8c tty_release+0x144/0x4c0 __fput+0x78/0x220 ____fput+0x1c/0x30 task_work_run+0x88/0xc0 do_notify_resume+0x8d0/0x123c el0_svc+0xa8/0xc0 el0t_64_sync_handler+0xa4/0x130 el0t_64_sync+0x1a0/0x1a4 Code: b9000083 b901f001 794038a0 8b000042 (b9000041) ---[ end trace 83dd93df15c3216f ]--- note: bootlogd[132] exited with preempt_count 1 /etc/rcS.d/S07bootlogd: line 47: 132 Segmentation fault start-stop-daemon This has been discussed in the Xen community, and we think it should fix this in Linux. See [2] for more information. [1] https://developer.arm.com/documentation/den0094/c/?lang=en [2] https://lists.xenproject.org/archives/html/xen-devel/2022-11/msg00543.html Fixes: 0dd1e247fd39 (drivers: PL011: add support for the ARM SBSA generic UART) Signed-off-by: Jiamei Xie <jiamei.xie@arm.com> Reviewed-by: Andre Przywara <andre.przywara@arm.com> Link: https://lore.kernel.org/r/20221117103237.86856-1-jiamei.xie@arm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-03serial: pl011: Use uart_xmit_advance()Ilpo Järvinen1-2/+1
Take advantage of the new uart_xmit_advance() helper. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20221019091151.6692-9-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-30serial: Make ->set_termios() old ktermios constIlpo Järvinen1-2/+2
There should be no reason to adjust old ktermios which is going to get discarded anyway. Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20220816115739.10928-7-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-30serial: pl011: Add reg-io-width parametersShubhrajyoti Datta1-0/+16
Some of the implementations can read only 32 bits because of the interface limitations of the port they are connected to. Add a parameter reg-io-width for supporting such platforms. Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@amd.com> Link: https://lore.kernel.org/r/20220826120559.2122-3-shubhrajyoti.datta@amd.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-08Merge tag 'tty-6.0-rc1' of ↵Linus Torvalds1-6/+9
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty Pull tty / serial driver updates from Greg KH: "Here is the big set of tty and serial driver changes for 6.0-rc1. It was delayed from last week as I wanted to make sure the last commit here got some good testing in linux-next and elsewhere as it seemed to show up only late in testing for some reason. Nothing major here, just lots of cleanups from Jiri and Ilpo to make the tty core cleaner (Jiri) and the rs485 code simpler to use (Ilpo). Also included in here is the obligatory n_gsm updates from Daniel Starke and lots of tiny driver updates and minor fixes and tweaks for other smaller serial drivers. All of these have been in linux-next for a while with no reported problems" * tag 'tty-6.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (186 commits) tty: serial: qcom-geni-serial: Fix %lu -> %u in print statements tty: amiserial: Fix comment typo tty: serial: document uart_get_console() tty: serial: serial_core, reformat kernel-doc for functions Documentation: serial: link uart_ops properly Documentation: serial: move GPIO kernel-doc to the functions Documentation: serial: dedup kernel-doc for uart functions Documentation: serial: move uart_ops documentation to the struct dt-bindings: serial: snps-dw-apb-uart: Document Rockchip RV1126 serial: mvebu-uart: uart2 error bits clearing tty: serial: fsl_lpuart: correct the count of break characters serial: stm32: make info structs static to avoid sparse warnings serial: fsl_lpuart: zero out parity bit in CS7 mode tty: serial: qcom-geni-serial: Fix get_clk_div_rate() which otherwise could return a sub-optimal clock rate. serial: 8250_bcm2835aux: Add missing clk_disable_unprepare() tty: vt: initialize unicode screen buffer serial: remove VR41XX serial driver serial: 8250: lpc18xx: Remove redundant sanity check for RS485 flags serial: 8250_dwlib: remove redundant sanity check for RS485 flags dt_bindings: rs485: Correct delay values ...
2022-07-08serial: Embed rs485_supported to uart_portIlpo Järvinen1-1/+1
Embed rs485_supported to uart_port to allow serial core to tweak it as needed. Reviewed-by: Lino Sanfilippo <l.sanfilippo@kunbus.com> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20220704094515.6831-2-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-06-27serial: pl011: UPSTAT_AUTORTS requires .throttle/unthrottleIlpo Järvinen1-2/+21
The driver must provide throttle and unthrottle in uart_ops when it sets UPSTAT_AUTORTS. Add them using existing stop_rx & enable_interrupts functions. Fixes: 2a76fa283098 (serial: pl011: Adopt generic flag to store auto RTS status) Cc: stable <stable@kernel.org> Cc: Lukas Wunner <lukas@wunner.de> Reported-by: Nuno Gonçalves <nunojpg@gmail.com> Tested-by: Nuno Gonçalves <nunojpg@gmail.com> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20220614075637.8558-1-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-06-27serial: take termios_rwsem for ->rs485_config() & pass termios as paramIlpo Järvinen1-1/+1
To be able to alter ADDRB within ->rs485_config(), take termios_rwsem before calling ->rs485_config() and pass termios. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20220624204210.11112-5-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-06-10serial: pl011: Remove serial_rs485 sanitizationIlpo Järvinen1-5/+0
Serial core handles serial_rs485 sanitization. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20220606100433.13793-30-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-06-10serial: pl011: Fill in rs485_supportedIlpo Järvinen1-0/+8
Add information on supported serial_rs485 features. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20220606100433.13793-13-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-05-19serial: amba-pl011: move header content to .cJiri Slaby1-2/+30
There is no point keeping the header content separated. In this case, it is only an enum. So move the enum to the appropriate source file. Cc: Russell King <linux@armlinux.org.uk> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20220519075720.31402-1-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-05-02Merge 5.18-rc5 into tty-nextGreg Kroah-Hartman1-2/+7
We need the tty/serial fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15serial: amba-pl011: do not time out prematurely when draining tx fifoLino Sanfilippo1-2/+7
The current timeout for draining the tx fifo in RS485 mode is calculated by multiplying the time it takes to transmit one character (with the given baud rate) with the maximal number of characters in the tx queue. This timeout is too short for two reasons: First when calculating the time to transmit one character integer division is used which may round down the result in case of a remainder of the division. Fix this by rounding up the division result. Second the hardware may need additional time (e.g for first putting the characters from the fifo into the shift register) before the characters are actually put onto the wire. To be on the safe side double the current maximum number of iterations that are used to wait for the queue draining. Fixes: 8d479237727c ("serial: amba-pl011: add RS485 support") Cc: stable@vger.kernel.org Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de> Link: https://lore.kernel.org/r/20220408233503.7251-1-LinoSanfilippo@gmx.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15serial: amba-pl011: remove redundant code in rs485_configLino Sanfilippo1-15/+1
In uart_set_rs485_config() the serial core already - ensures that only one of both options RTS on send or RTS after send is set - nullifies the padding field of the passed serial_rs485 struct - clamps the RTS delays - assigns the passed serial_rs485 struct to the uart port So remove these tasks from the code of the drivers rs485_config() function to avoid redundancy. Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de> Link: https://lore.kernel.org/r/20220410104642.32195-3-LinoSanfilippo@gmx.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-03-03serial: make uart_console_write->putchar()'s character an unsigned charJiri Slaby1-3/+3
Currently, uart_console_write->putchar's second parameter (the character) is of type int. It makes little sense, provided uart_console_write() accepts the input string as "const char *s" and passes its content -- the characters -- to putchar(). So switch the character's type to unsigned char. We don't use char as that is signed on some platforms. That would cause troubles for drivers which (implicitly) cast the char to u16 when writing to the device. Sign extension would happen in that case and the value written would be completely different to the provided char. DZ is an example of such a driver -- on MIPS, it uses u16 for dz_out in dz_console_putchar(). Note we do the char -> uchar conversion implicitly in uart_console_write(). Provided we do not change size of the data type, sign extension does not happen there, so the problem is void. This makes the types consistent and unified with the rest of the uart layer, which uses unsigned char in most places already. One exception is xmit_buf, but that is going to be converted later. Cc: Paul Cercueil <paul@crapouillou.net> Cc: Tobias Klauser <tklauser@distanz.ch> Cc: Russell King <linux@armlinux.org.uk> Cc: Vineet Gupta <vgupta@kernel.org> Cc: Nicolas Ferre <nicolas.ferre@microchip.com> Cc: Alexandre Belloni <alexandre.belloni@bootlin.com> Cc: Ludovic Desroches <ludovic.desroches@microchip.com> Cc: Florian Fainelli <f.fainelli@gmail.com> Cc: bcm-kernel-feedback-list@broadcom.com Cc: Alexander Shiyan <shc_work@mail.ru> Cc: Baruch Siach <baruch@tkos.co.il> Cc: "Maciej W. Rozycki" <macro@orcam.me.uk> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Shawn Guo <shawnguo@kernel.org> Cc: Sascha Hauer <s.hauer@pengutronix.de> Cc: Pengutronix Kernel Team <kernel@pengutronix.de> Cc: Fabio Estevam <festevam@gmail.com> Cc: NXP Linux Team <linux-imx@nxp.com> Cc: Karol Gugala <kgugala@antmicro.com> Cc: Mateusz Holenko <mholenko@antmicro.com> Cc: Vladimir Zapolskiy <vz@mleia.com> Cc: Neil Armstrong <narmstrong@baylibre.com> Cc: Kevin Hilman <khilman@baylibre.com> Cc: Jerome Brunet <jbrunet@baylibre.com> Cc: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Cc: Taichi Sugaya <sugaya.taichi@socionext.com> Cc: Takao Orito <orito.takao@socionext.com> Cc: Liviu Dudau <liviu.dudau@arm.com> Cc: Sudeep Holla <sudeep.holla@arm.com> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: "Andreas Färber" <afaerber@suse.de> Cc: Manivannan Sadhasivam <mani@kernel.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Andy Gross <agross@kernel.org> Cc: Bjorn Andersson <bjorn.andersson@linaro.org> Cc: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com> Cc: Orson Zhai <orsonzhai@gmail.com> Cc: Baolin Wang <baolin.wang7@gmail.com> Cc: Chunyan Zhang <zhang.lyra@gmail.com> Cc: Patrice Chotard <patrice.chotard@foss.st.com> Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com> Cc: Alexandre Torgue <alexandre.torgue@foss.st.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Peter Korsgaard <peter@korsgaard.com> Cc: Michal Simek <michal.simek@xilinx.com> Acked-by: Richard Genoud <richard.genoud@gmail.com> [atmel_serial] Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Acked-by: Paul Cercueil <paul@crapouillou.net> Acked-by: Neil Armstrong <narmstrong@baylibre.com> # meson_serial Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20220303080831.21783-1-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-26serial: core: Initialize rs485 RTS polarity already on probeLukas Wunner1-14/+1
RTS polarity of rs485-enabled ports is currently initialized on uart open via: tty_port_open() tty_port_block_til_ready() tty_port_raise_dtr_rts() # if (C_BAUD(tty)) uart_dtr_rts() uart_port_dtr_rts() There's at least three problems here: First, if no baud rate is set, RTS polarity is not initialized. That's the right thing to do for rs232, but not for rs485, which requires that RTS is deasserted unconditionally. Second, if the DeviceTree property "linux,rs485-enabled-at-boot-time" is present, RTS should be deasserted as early as possible, i.e. on probe. Otherwise it may remain asserted until first open. Third, even though RTS is deasserted on open and close, it may subsequently be asserted by uart_throttle(), uart_unthrottle() or uart_set_termios() because those functions aren't rs485-aware. (Only uart_tiocmset() is.) To address these issues, move RTS initialization from uart_port_dtr_rts() to uart_configure_port(). Prevent subsequent modification of RTS polarity by moving the existing rs485 check from uart_tiocmget() to uart_update_mctrl(). That way, RTS is initialized on probe and then remains unmodified unless the uart transmits data. If rs485 is enabled at runtime (instead of at boot) through a TIOCSRS485 ioctl(), RTS is initialized by the uart driver's ->rs485_config() callback and then likewise remains unmodified. The PL011 driver initializes RTS on uart open and prevents subsequent modification in its ->set_mctrl() callback. That code is obsoleted by the present commit, so drop it. Cc: Jan Kiszka <jan.kiszka@siemens.com> Cc: Su Bao Cheng <baocheng.su@siemens.com> Signed-off-by: Lukas Wunner <lukas@wunner.de> Link: https://lore.kernel.org/r/2d2acaf3a69e89b7bf687c912022b11fd29dfa1e.1642909284.git.lukas@wunner.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-26serial: pl011: Fix incorrect rs485 RTS polarity on set_mctrlJochen Mades1-2/+6
Commit 8d479237727c ("serial: amba-pl011: add RS485 support") sought to keep RTS deasserted on set_mctrl if rs485 is enabled. However it did so only if deasserted RTS polarity is high. Fix it in case it's low. Fixes: 8d479237727c ("serial: amba-pl011: add RS485 support") Cc: stable@vger.kernel.org # v5.15+ Cc: Lino Sanfilippo <LinoSanfilippo@gmx.de> Signed-off-by: Jochen Mades <jochen@mades.net> [lukas: copyedit commit message, add stable designation] Signed-off-by: Lukas Wunner <lukas@wunner.de> Link: https://lore.kernel.org/r/85fa3323ba8c307943969b7343e23f34c3e652ba.1642909284.git.lukas@wunner.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-06serial: pl011: Drop redundant DTR/RTS preservation on close/openLukas Wunner1-5/+2
Commit d8d8ffa47783 ("amba-pl011: do not disable RTS during shutdown") amended the PL011 serial driver to leave DTR/RTS polarity untouched on tty close. That change made sense. But the commit also added code to save DTR/RTS state to an internal variable on tty close and restore it on tty open. That part of the commit makes less sense: The driver has no ->pm() callback, so the uart remains powered after tty close and automatically preserves register state, including DTR/RTS. Saving and restoring registers isn't the job of the ->startup() and ->shutdown() callbacks anyway. Rather, it should happen in ->pm(). Additionally, after pl011_startup() restores the state, the serial core overrides it in uart_port_dtr_rts() if a baud rate has been set: tty_port_open() uart_port_activate() uart_startup() uart_port_startup() pl011_startup() # restores DTR/RTS from uap->old_cr tty_port_block_til_ready() tty_port_raise_dtr_rts # if (C_BAUD(tty)) uart_dtr_rts() uart_port_dtr_rts() # raises DTR/RTS The serial core also overrides DTR/RTS on tty close in uart_shutdown() if C_HUPCL(tty) is set. So a user-defined DTR/RTS polarity won't survive a close/open cycle anyway, unless the user has set the baud rate to zero and disabled hupcl on the tty. Bottom line is, the code to save and restore DTR/RTS has no effect. Remove it. Cc: Linus Walleij <linus.walleij@linaro.org> Cc: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Lukas Wunner <lukas@wunner.de> Link: https://lore.kernel.org/r/e22089ab49e6e78822c50c8c4db46bf3ee885623.1641129328.git.lukas@wunner.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-06serial: pl011: Drop CR register reset on set_termiosLukas Wunner1-2/+0
pl011_set_termios() briefly resets the CR register to zero, thereby glitching DTR/RTS signals. With rs485 this may result in the bus being occupied for no reason. Where does this register write originate from? The PL011 driver was forked from the PL010 driver in 2004: https://git.kernel.org/history/history/c/157c0342e591 Until this commit, the PL010 driver's IRQ handler ambauart_int() modified the CR register without holding the port spinlock. ambauart_set_termios() also modified that register. To prevent concurrent read-modify-writes by the IRQ handler and to prevent transmission while changing baudrate, ambauart_set_termios() had to disable interrupts. On the PL010, that is achieved by writing zero to the CR register. However, on the PL011, interrupts are disabled in the IMSC register, not in the CR register. Additionally, the commit amended both the PL010 and PL011 driver to acquire the port spinlock in the IRQ handler, obviating the need to disable interrupts in ->set_termios(). So the CR register write is obsolete for two reasons. Drop it. Cc: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Lukas Wunner <lukas@wunner.de> Link: https://lore.kernel.org/r/f49f945375f5ccb979893c49f1129f51651ac738.1641129062.git.lukas@wunner.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-06Merge 5.16-rc4 into tty-nextGreg Kroah-Hartman1-0/+1
We need the tty/serial driver fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-03serial: amba-pl011: do not request memory region twiceLino Sanfilippo1-24/+3
With commit 3873e2d7f63a ("drivers: PL011: refactor pl011_probe()") the function devm_ioremap() called from pl011_setup_port() was replaced with devm_ioremap_resource(). Since this function not only remaps but also requests the ports io memory region it now collides with the .config_port() callback which requests the same region at uart port registration. Since devm_ioremap_resource() already claims the memory successfully, the request in .config_port() fails. Later at uart port deregistration the attempt to release the unclaimed memory also fails. The failure results in a “Trying to free nonexistent resource" warning. Fix these issues by removing the callbacks that implement the redundant memory allocation/release. Also make sure that changing the drivers io memory base address via TIOCSSERIAL is not allowed any more. Fixes: 3873e2d7f63a ("drivers: PL011: refactor pl011_probe()") Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de> Link: https://lore.kernel.org/r/20211129174238.8333-1-LinoSanfilippo@gmx.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25arm: remove zte zx platform left-overLukas Bulwahn1-37/+0
Commit 89d4f98ae90d ("ARM: remove zte zx platform") missed to remove some definitions for this platform's debug and serial, e.g., code dependent on the config DEBUG_ZTE_ZX. Fortunately, ./scripts/checkkconfigsymbols.py detects this and warns: DEBUG_ZTE_ZX Referencing files: arch/arm/include/debug/pl01x.S Further review by Arnd Bergmann identified even more dead code in the amba serial driver. Remove all this left-over from the zte zx platform. Reviewed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com> Link: https://lore.kernel.org/r/20211102063810.932-1-lukas.bulwahn@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25serial: pl011: Add ACPI SBSA UART match idPierre Gondois1-0/+1
The document 'ACPI for Arm Components 1.0' defines the following _HID mappings: -'Prime cell UART (PL011)': ARMH0011 -'SBSA UART': ARMHB000 Use the sbsa-uart driver when a device is described with the 'ARMHB000' _HID. Note: PL011 devices currently use the sbsa-uart driver instead of the uart-pl011 driver. Indeed, PL011 devices are not bound to a clock in ACPI. It is not possible to change their baudrate. Cc: <stable@vger.kernel.org> Signed-off-by: Pierre Gondois <Pierre.Gondois@arm.com> Link: https://lore.kernel.org/r/20211109172248.19061-1-Pierre.Gondois@arm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-16Revert "arm pl011 serial: support multi-irq request"Qian Cai1-31/+3
This reverts commit b0819465be8be0c76af15436a9e6db4dab4c196e which results in amba_device-specific code being called from sbsa_uart_startup() and sbsa_uart_shutdown(). Signed-off-by: Qian Cai <quic_qiancai@quicinc.com> Link: https://lore.kernel.org/r/20210813163135.205-1-quic_qiancai@quicinc.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-21arm pl011 serial: support multi-irq requestBing Fan1-3/+31
In order to make pl011 work better, multiple interrupts are required, such as TXIM, RXIM, RTIM, error interrupt(FE/PE/BE/OE); at the same time, pl011 to GIC does not merge the interrupt lines(each serial-interrupt corresponding to different GIC hardware interrupt), so need to enable and request multiple gic interrupt numbers in the driver. Signed-off-by: Bing Fan <tombinfan@tencent.com> Link: https://lore.kernel.org/r/1625103512-30182-1-git-send-email-hptsfb@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-21serial: amba-pl011: add RS485 supportLino Sanfilippo1-2/+161
Add basic support for RS485: Provide a callback to configure RS485 settings. Handle the RS485 specific part in the functions pl011_rs485_tx_start() and pl011_rs485_tx_stop() which extend the generic start/stop callbacks. Beside via IOCTL from userspace RS485 can be enabled by means of the device tree property "rs485-enabled-at-boot-time". Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de> Link: https://lore.kernel.org/r/20210630225644.3744-1-LinoSanfilippo@gmx.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-20serial: drop irq-flags initialisationsJohan Hovold1-1/+1
There's no need to initialise irq-flags variables before saving the interrupt state. Drop the redundant initialisations from drivers that got this wrong. Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20210519092541.10137-1-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>