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path: root/drivers/tty/serial/fsl_lpuart.c
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2024-03-05tty: serial: fsl_lpuart: avoid idle preamble pending if CTS is enabledSherry Sun
If the remote uart device is not connected or not enabled after booting up, the CTS line is high by default. At this time, if we enable the flow control when opening the device(for example, using “stty -F /dev/ttyLP4 crtscts” command), there will be a pending idle preamble(first writing 0 and then writing 1 to UARTCTRL_TE will queue an idle preamble) that cannot be sent out, resulting in the uart port fail to close(waiting for TX empty), so the user space stty will have to wait for a long time or forever. This is an LPUART IP bug(idle preamble has higher priority than CTS), here add a workaround patch to enable TX CTS after enabling UARTCTRL_TE, so that the idle preamble does not get stuck due to CTS is deasserted. Fixes: 380c966c093e ("tty: serial: fsl_lpuart: add 32-bit register interface support") Cc: stable <stable@kernel.org> Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Reviewed-by: Alexander Sverdlin <alexander.sverdlin@siemens.com> Link: https://lore.kernel.org/r/20240305015706.1050769-1-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-23serial: fsl_lpuart: Convert to platform remove callback returning voidUwe Kleine-König
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/20231110152927.70601-17-u.kleine-koenig@pengutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-09-18serial: fsl_lpuart: Use port lock wrappersThomas Gleixner
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/20230914183831.587273-28-john.ogness@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-20Merge commit b320441c04c9 ("Merge tag 'tty-6.5-rc7' of ↵Greg Kroah-Hartman
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty") into tty-next We need the serial-core fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-01tty: serial: fsl_lpuart: Clear the error flags by writing 1 for lpuart32 ↵Sherry Sun
platforms Do not read the data register to clear the error flags for lpuart32 platforms, the additional read may cause the receive FIFO underflow since the DMA has already read the data register. Actually all lpuart32 platforms support write 1 to clear those error bits, let's use this method to better clear the error flags. Fixes: 42b68768e51b ("serial: fsl_lpuart: DMA support for 32-bit variant") Cc: stable <stable@kernel.org> Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Link: https://lore.kernel.org/r/20230801022304.24251-1-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-25serial: fsl_lpuart: Use devm_platform_get_and_ioremap_resource()Yangtao Li
Convert platform_get_resource(), devm_ioremap_resource() to a single call to devm_platform_get_and_ioremap_resource(), as this is exactly what this function does. Signed-off-by: Yangtao Li <frank.li@vivo.com> Link: https://lore.kernel.org/r/20230712062853.11007-7-frank.li@vivo.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-25tty: serial: fsl_lpuart: add IDLE interrupt support for rx_dma on ↵Sherry Sun
imx7ulp/imx8ulp/imx8qxp Add IDLE interrupt support for receive dma on imx7ulp/imx8ulp/imx8qxp platforms to replace the receive dma timer function, because the receive dma timer has bigger latency than idle interrupt triggering, which may cause the Bluetooth Firmware download timeout on Android platform(it has a limited FW download time window). Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Link: https://lore.kernel.org/r/20230710013857.7396-3-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-25tty: serial: fsl_lpuart: move the lpuart32_int() belowSherry Sun
Move the lpuart32_int() below lpuart_copy_rx_to_tty(), this is a preparation patch for the next patch to avoid the function declaration, no actual functional changes. Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Link: https://lore.kernel.org/r/20230710013857.7396-2-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-25tty: Explicitly include correct DT includesRob Herring
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>
2023-07-03Merge tag 'tty-6.5-rc1' of ↵Linus Torvalds
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/serial driver updates for 6.5-rc1. Included in here are: - tty_audit code cleanups from Jiri - more 8250 cleanups from Ilpo - samsung_tty driver bugfixes - 8250 lock port updates - usual fsl_lpuart driver updates and fixes - other small serial driver fixes and updates, full details in the shortlog All of these have been in linux-next for a while with no reported issues" * tag 'tty-6.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (58 commits) tty_audit: make data of tty_audit_log() const tty_audit: make tty pointers in exposed functions const tty_audit: make icanon a bool tty_audit: invert the condition in tty_audit_log() tty_audit: use kzalloc() in tty_audit_buf_alloc() tty_audit: use TASK_COMM_LEN for task comm Revert "8250: add support for ASIX devices with a FIFO bug" serial: atmel: don't enable IRQs prematurely tty: serial: Add Nuvoton ma35d1 serial driver support tty: serial: fsl_lpuart: add earlycon for imx8ulp platform tty: serial: imx: fix rs485 rx after tx selftests: tty: add selftest for tty timestamp updates tty: tty_io: update timestamps on all device nodes tty: fix hang on tty device with no_room set serial: core: fix -EPROBE_DEFER handling in init serial: 8250_omap: Use force_suspend and resume for system suspend tty: serial: samsung_tty: Use abs() to simplify some code tty: serial: samsung_tty: Fix a memory leak in s3c24xx_serial_getclk() when iterating clk tty: serial: samsung_tty: Fix a memory leak in s3c24xx_serial_getclk() in case of error serial: 8250: Apply FSL workarounds also without SERIAL_8250_CONSOLE ...
2023-06-19tty: serial: fsl_lpuart: add earlycon for imx8ulp platformSherry Sun
Add earlycon support for imx8ulp platform. Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Cc: stable <stable@kernel.org> Link: https://lore.kernel.org/r/20230619080613.16522-1-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-13tty: serial: fsl_lpuart: reduce RX watermark to 0 on LS1028ARobert Hodaszi
LS1028A is using DMA with LPUART. Having RX watermark set to 1, means DMA transactions are started only after receiving the second character. On other platforms with newer LPUART IP, Receiver Idle Empty function initiates the DMA request after the receiver is idling for 4 characters. But this feature is missing on LS1028A, which is causing a 1-character delay in the RX direction on this platform. Set RX watermark to 0 to initiate RX DMA after each character. Link: https://lore.kernel.org/linux-serial/20230607103459.1222426-1-robert.hodaszi@digi.com/ Fixes: 9ad9df844754 ("tty: serial: fsl_lpuart: Fix the wrong RXWATER setting for rx dma case") Cc: stable <stable@kernel.org> Signed-off-by: Robert Hodaszi <robert.hodaszi@digi.com> Message-ID: <20230609121334.1878626-1-robert.hodaszi@digi.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-05Merge 6.4-rc5 into tty-nextGreg Kroah-Hartman
We need the tty fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-30tty: serial: fsl_lpuart: use UARTCTRL_TXINV to send break instead of ↵Sherry Sun
UARTCTRL_SBK LPUART IP now has two known bugs, one is that CTS has higher priority than the break signal, which causes the break signal sending through UARTCTRL_SBK may impacted by the CTS input if the HW flow control is enabled. It exists on all platforms we support in this driver. So we add a workaround patch for this issue: commit c4c81db5cf8b ("tty: serial: fsl_lpuart: disable the CTS when send break signal"). Another IP bug is i.MX8QM LPUART may have an additional break character being sent after SBK was cleared. It may need to add some delay between clearing SBK and re-enabling CTS to ensure that the SBK latch are completely cleared. But we found that during the delay period before CTS is enabled, there is still a risk that Bluetooth data in TX FIFO may be sent out during this period because of break off and CTS disabled(even if BT sets CTS line deasserted, data is still sent to BT). Due to this risk, we have to drop the CTS-disabling workaround for SBK bugs, use TXINV seems to be a better way to replace SBK feature and avoid above risk. Also need to disable the transmitter to prevent any data from being sent out during break, then invert the TX line to send break. Then disable the TXINV when turn off break and re-enable transmitter. Fixes: c4c81db5cf8b ("tty: serial: fsl_lpuart: disable the CTS when send break signal") Cc: stable <stable@kernel.org> Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Link: https://lore.kernel.org/r/20230519094751.28948-1-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-30tty: serial: fsl_lpuart: Check the return value of dmaengine_tx_statusSherry Sun
Coverity reports the Unchecked return value (CHECKED_RETURN) warning: Calling dmaengine_tx_status without checking return value. So here add the return value check for dmaengine_tx_status() function to make coverity happy. Fixes: cf9aa72d2f91 ("tty: serial: fsl_lpuart: optimize the timer based EOP logic") Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Link: https://lore.kernel.org/r/20230522025111.3747-1-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-13tty: serial: fsl_lpuart: optimize the timer based EOP logicShenwei Wang
DMA transfer may end prematurely due to the DMA Rx timeout even during an active transfer because a constant timeout does not accurately simulate an EOP (End Of Package) event. This patch uses a timer to simulate the hardware EOP event. The timer should only complete a DMA transfer once the idle period satisfies a specified interval which is baud rate dependent. The problem has been observed with low baud rates but could occur also with high baud rates. Make the DMA Rx timeout baud rate dependent and check the DMA residue count before copying data to the TTY buffer. If the residue count remains unchanged since the last interrupt, that indicates no new data was received. In this case, the DMA should complete as an EOP event. Otherwise, new data was received during the interval and the EOP condition is not met so restart the DMA Rx timeout Signed-off-by: Shenwei Wang <shenwei.wang@nxp.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20230510203359.1353469-1-shenwei.wang@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-20tty: serial: fsl_lpuart: use UARTMODIR register bits for lpuart32 platformSherry Sun
For lpuart32 platforms, UARTMODIR register is used instead of UARTMODEM. So here should configure the corresponding UARTMODIR register bits to avoid confusion. Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Link: https://lore.kernel.org/r/20230414022111.20896-1-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-20tty: serial: fsl_lpuart: adjust buffer length to the intended sizeShenwei Wang
Based on the fls function definition provided below, we should not subtract 1 to obtain the correct buffer length: fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32. Fixes: 5887ad43ee02 ("tty: serial: fsl_lpuart: Use cyclic DMA for Rx") Signed-off-by: Shenwei Wang <shenwei.wang@nxp.com> Link: https://lore.kernel.org/r/20230410195555.1003900-1-shenwei.wang@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-29tty: serial: fsl_lpuart: fix crash in lpuart_uport_is_activeSherry Sun
For serdev framework, tty->dev is a NULL pointer, lpuart_uport_is_active calling device_may_wakeup() may cause kernel NULL pointer crash, so here add the NULL pointer check before using it. Fixes: 4f5cb8c5e915 ("tty: serial: fsl_lpuart: enable wakeup source for lpuart") Cc: stable <stable@kernel.org> Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Link: https://lore.kernel.org/r/20230323110923.24581-1-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-29tty: serial: fsl_lpuart: avoid checking for transfer complete when ↵Sherry Sun
UARTCTRL_SBK is asserted in lpuart32_tx_empty According to LPUART RM, Transmission Complete Flag becomes 0 if queuing a break character by writing 1 to CTRL[SBK], so here need to avoid checking for transmission complete when UARTCTRL_SBK is asserted, otherwise the lpuart32_tx_empty may never get TIOCSER_TEMT. Commit 2411fd94ceaa("tty: serial: fsl_lpuart: skip waiting for transmission complete when UARTCTRL_SBK is asserted") only fix it in lpuart32_set_termios(), here also fix it in lpuart32_tx_empty(). Fixes: 380c966c093e ("tty: serial: fsl_lpuart: add 32-bit register interface support") Cc: stable <stable@kernel.org> Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Link: https://lore.kernel.org/r/20230323054415.20363-1-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-09tty: serial: fsl_lpuart: fix race on RX DMA shutdownAlexander Sverdlin
From time to time DMA completion can come in the middle of DMA shutdown: <process ctx>: <IRQ>: lpuart32_shutdown() lpuart_dma_shutdown() del_timer_sync() lpuart_dma_rx_complete() lpuart_copy_rx_to_tty() mod_timer() lpuart_dma_rx_free() When the timer fires a bit later, sport->dma_rx_desc is NULL: Unable to handle kernel NULL pointer dereference at virtual address 0000000000000004 pc : lpuart_copy_rx_to_tty+0xcc/0x5bc lr : lpuart_timer_func+0x1c/0x2c Call trace: lpuart_copy_rx_to_tty lpuart_timer_func call_timer_fn __run_timers.part.0 run_timer_softirq __do_softirq __irq_exit_rcu irq_exit handle_domain_irq gic_handle_irq call_on_irq_stack do_interrupt_handler ... To fix this fold del_timer_sync() into lpuart_dma_rx_free() after dmaengine_terminate_sync() to make sure timer will not be re-started in lpuart_copy_rx_to_tty() <= lpuart_dma_rx_complete(). Fixes: 4a8588a1cf86 ("serial: fsl_lpuart: delete timer on shutdown") Cc: stable <stable@kernel.org> Signed-off-by: Alexander Sverdlin <alexander.sverdlin@siemens.com> Link: https://lore.kernel.org/r/20230309134302.74940-2-alexander.sverdlin@siemens.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-09tty: serial: fsl_lpuart: skip waiting for transmission complete when ↵Sherry Sun
UARTCTRL_SBK is asserted According to LPUART RM, Transmission Complete Flag becomes 0 if queuing a break character by writing 1 to CTRL[SBK], so here need to skip waiting for transmission complete when UARTCTRL_SBK is asserted, otherwise the kernel may stuck here. And actually set_termios() adds transmission completion waiting to avoid data loss or data breakage when changing the baud rate, but we don't need to worry about this when queuing break characters. Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Cc: stable <stable@kernel.org> Link: https://lore.kernel.org/r/20230223093941.31790-1-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-02-08serial: fsl_lpuart: fix RS485 RTS polariy inverse issueShenwei Wang
The previous 'commit 846651eca073 ("serial: fsl_lpuart: RS485 RTS polariy is inverse")' only fixed the inverse issue on lpuart 8bit platforms. This is a follow-up patch to fix the RS485 polarity inverse issue on lpuart 32bit platforms. Fixes: 03895cf41d18 ("tty: serial: fsl_lpuart: Add support for RS-485") Reported-by: Sherry Sun <sherry.sun@nxp.com> Signed-off-by: Shenwei Wang <shenwei.wang@nxp.com> Link: https://lore.kernel.org/r/20230207162420.3647904-1-shenwei.wang@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-31tty: serial: fsl_lpuart: add imx8ulp supportSherry Sun
The lpuart of imx8ulp is basically the same as imx7ulp, but it supports some new features based on imx7ulp, such as it can assert the DMA request on EOP(end-of-packet). Here add lpuart support for imx8ulp, and rx_watermark is set to 3 as imx8ulp RX FIFO depth is 8. Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Link: https://lore.kernel.org/r/20230130064449.9564-7-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-31tty: serial: fsl_lpuart: set RTS watermark for lpuartSherry Sun
Add RTS watermark support for LPUART. The RX RTS_B output negates when the number of empty words in the receive FIFO is greater or equal to RTSWATER. Here set the RTSWATER to half of the rxfifo_size. Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Link: https://lore.kernel.org/r/20230130064449.9564-6-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-31tty: serial: fsl_lpuart: Enable Receiver Idle Empty function for LPUARTSherry Sun
With the growth of rx watermark, it's useful to enable the Receiver Idle Empty function, it can assert the RDRF(Receive Data Register Full Flag) when the receiver is idle for a number of idle characters and the FIFO is not empty. It will generate a DMA request or interrupt, which can avoid receive data being trapped in the RX FIFO since the number of words received is less than the watermark. Here set the RXIDEN as 0x3 which enable the RDRF assertion due to partially filled FIFO when receiver is idle for 4 characters. Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Link: https://lore.kernel.org/r/20230130064449.9564-5-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-31tty: serial: fsl_lpuart: Fix the wrong RXWATER setting for rx dma caseSherry Sun
The RXWATER value must be greater than 0 according to the LPUART reference manual. And when the number of datawords in the receive FIFO is greater than RXWATER, an interrupt or a DMA request is generated, so no need to set the different value for lpuart interrupt case and dma case. Here delete the wrong RXWATER setting for dma case directly. Fixes: 42b68768e51b ("serial: fsl_lpuart: DMA support for 32-bit variant") Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Link: https://lore.kernel.org/r/20230130064449.9564-4-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-31tty: serial: fsl_lpuart: set receive watermark for imx8qxp platformSherry Sun
Since imx8qxp RX FIFO depth is 64 datawords, it will be better to set the rx watermark as 31, which means when the number of datawords in the receive FIFO(>= 32) is greater than the watermark, an interrupt or a DMA request is generated. Also keep the console rx watermark as 1 to make sure it responsive. Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Link: https://lore.kernel.org/r/20230130064449.9564-3-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-31tty: serial: fsl_lpuart: make rx_watermark configurable for different platformsSherry Sun
Add rx_watermark parameter for struct lpuart_port to make the receive watermark configurable for different platforms. No function changed. Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Link: https://lore.kernel.org/r/20230130064449.9564-2-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-31tty: serial: fsl_lpuart: don't enable receiver/transmitter before rx/tx dma ↵Sherry Sun
ready lpuart32_setup_watermark_enable() will configure the UART FIFO and watermark, also enable the receiver and transmitter, this should be done after the rx/tx dma steup ready. Also add lpuart32_hw_disable() to make sure the receiver/transmitter and interrupts are disabled during the dma steup. Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Link: https://lore.kernel.org/r/20230130054107.9119-1-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19tty: serial: fsl_lpuart: increase maximum uart_nr to eightNate Drude
Some SoCs like the i.MX93 have aliases for up to eight UARTs, see: https://github.com/torvalds/linux/blob/v6.1/arch/arm64/boot/dts/freescale/imx93.dtsi#L31-L38 Increase UART_NR from 6 to 8 to support lpuart7 and lpuart8 and avoid initialization failures like the following: [ 0.837146] fsl-lpuart 42690000.serial: serial6 out of range [ 0.842814] fsl-lpuart: probe of 42690000.serial failed with error -22 Signed-off-by: Nate Drude <nate.d@variscite.com> Reviewed-by: Sherry Sun <sherry.sun@nxp.com> Link: https://lore.kernel.org/r/20221222145634.2217793-1-nate.d@variscite.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19tty: serial: fsl_lpuart: disable the break condition when shutdown the uart portSherry Sun
Need to disable the break condition for lpuart driver when closing the uart port like other uart drivers do. Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Link: https://lore.kernel.org/r/20221214031137.28815-3-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19tty: serial: fsl_lpuart: disable the CTS when send break signalSherry Sun
LPUART IP has a bug that it treats the CTS as higher priority than the break signal, which cause the break signal sending through UARTCTRL_SBK may impacted by the CTS input if the HW flow control is enabled. Add this workaround patch to fix the IP bug, we can disable CTS before asserting SBK to avoid any interference from CTS, and re-enable it when break off. Such as for the bluetooth chip power save feature, host can let the BT chip get into sleep state by sending a UART break signal, and wake it up by turning off the UART break. If the BT chip enters the sleep mode successfully, it will pull up the CTS line, if the BT chip is woken up, it will pull down the CTS line. If without this workaround patch, the UART TX pin cannot send the break signal successfully as it affected by the BT CTS pin. After adding this patch, the BT power save feature can work well. Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Link: https://lore.kernel.org/r/20221214031137.28815-2-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19tty: serial: fsl_lpuart: clear LPUART Status Register in lpuart32_shutdown()Sherry Sun
The LPUART Status Register needs to be cleared when closing the uart port to get a clean environment when reopening the uart. Fixes: 380c966c093e ("tty: serial: fsl_lpuart: add 32-bit register interface support") Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Link: https://lore.kernel.org/r/20221125101953.18753-4-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19tty: serial: fsl_lpuart: disable Rx/Tx DMA in lpuart32_shutdown()Sherry Sun
UARTBAUD_RDMAE and UARTBAUD_TDMAE are enabled in lpuart32_startup(), but lpuart32_shutdown() not disable them, only free the dma ring buffer and release the dma channels, so here disable the Rx/Tx DMA first in lpuart32_shutdown(). Fixes: 42b68768e51b ("serial: fsl_lpuart: DMA support for 32-bit variant") Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Link: https://lore.kernel.org/r/20221125101953.18753-3-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-19tty: serial: fsl_lpuart: only enable Idle Line Interrupt for non-dma caseSherry Sun
For the lpuart driver, the Idle Line Interrupt Enable now is only needed for the CPU mode, so enable the UARTCTRL_ILIE at the correct place, and clear it when shutdown. Also need to configure the suitable UARTCTRL_IDLECFG, now the value is 0x7, represent 128 idle characters will trigger the Idle Line Interrupt. Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Link: https://lore.kernel.org/r/20221125101953.18753-2-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-23tty: serial: fsl_lpuart: switch to new dmaengine_terminate_* APISherry Sun
Convert dmaengine_terminate_all() calls to synchronous and asynchronous versions where appropriate. Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Link: https://lore.kernel.org/r/20221123023619.30173-1-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-22tty: serial: fsl_lpuart: Use pm_ptr() to avoid need to make pm __maybe_unusedSherry Sun
Use pm_ptr() to remove the need to mark the pm functions as __maybe_unused when the kernel is built without CONFIG_PM support. Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Link: https://lore.kernel.org/r/20221110113859.8485-4-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-22tty: serial: fsl_lpuart: Add runtime pm supportSherry Sun
Add runtime pm support to manage the lpuart clock. Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Link: https://lore.kernel.org/r/20221110113859.8485-3-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-22tty: serial: fsl_lpuart: enable wakeup source for lpuartSherry Sun
LPUART supports both synchronous wakeup and asynchronous wakeup(wakeup the system when the UART clocks are shut-off), the synchronous wakeup is configured by UARTCTRL_RIE interrupt, and the asynchronous wakeup is configured by UARTBAUD_RXEDGIE interrupt. Add lpuart_uport_is_active() to determine if the uart port needs to get into the suspend states, also add lpuart_suspend_noirq() and lpuart_resume_noirq() to enable and disable the wakeup irq bits if the uart port needs to be set as wakeup source. When use lpuart with DMA mode, it still needs to switch to the cpu mode in .suspend() that enable cpu interrupts RIE and RXEDGIE as wakeup source, after system resume back, needs to setup DMA again, .resume() will share the HW setup code with .startup(), so abstract the same code to the api like lpuart32_hw_setup(). Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Link: https://lore.kernel.org/r/20221110113859.8485-2-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-22Merge 6.1-rc6 into tty-nextGreg Kroah-Hartman
We need the tty/serial fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-03tty: serial: fsl_lpuart: don't break the on-going transfer when global resetSherry Sun
lpuart_global_reset() shouldn't break the on-going transmit engine, need to recover the on-going data transfer after reset. This can help earlycon here, since commit 60f361722ad2 ("serial: fsl_lpuart: Reset prior to registration") moved lpuart_global_reset() before uart_add_one_port(), earlycon is writing during global reset, as global reset will disable the TX and clear the baud rate register, which caused the earlycon cannot work any more after reset, needs to restore the baud rate and re-enable the transmitter to recover the earlycon write. Also move the lpuart_global_reset() down, then we can reuse the lpuart32_tx_empty() without declaration. Fixes: bd5305dcabbc ("tty: serial: fsl_lpuart: do software reset for imx7ulp and imx8qxp") Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Link: https://lore.kernel.org/r/20221024085844.22786-1-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-03serial: fsl_lpuart: Use uart_xmit_advance()Ilpo Järvinen
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/20221019091151.6692-17-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-03tty: serial: use uart_port_tx() helperJiri Slaby (SUSE)
uart_port_tx() is a new helper to send characters to the device. Use it in these drivers. Cc: Tobias Klauser <tklauser@distanz.ch> 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: Vladimir Zapolskiy <vz@mleia.com> Cc: Liviu Dudau <liviu.dudau@arm.com> Cc: Sudeep Holla <sudeep.holla@arm.com> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.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: "Andreas Färber" <afaerber@suse.de> Cc: Manivannan Sadhasivam <mani@kernel.org> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org> Link: https://lore.kernel.org/r/20221004104927.14361-3-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-25serial: Deassert Transmit Enable on probe in driver-specific wayLukas Wunner
When a UART port is newly registered, uart_configure_port() seeks to deassert RS485 Transmit Enable by setting the RTS bit in port->mctrl. However a number of UART drivers interpret a set RTS bit as *assertion* instead of deassertion: Affected drivers include those using serial8250_em485_config() (except 8250_bcm2835aux.c) and some using mctrl_gpio (e.g. imx.c). Since the interpretation of the RTS bit is driver-specific, it is not suitable as a means to centrally deassert Transmit Enable in the serial core. Instead, the serial core must call on drivers to deassert it in their driver-specific way. One way to achieve that is to call ->rs485_config(). It implicitly deasserts Transmit Enable. So amend uart_configure_port() and uart_resume_port() to invoke uart_rs485_config(). That allows removing calls to uart_rs485_config() from drivers' ->probe() hooks and declaring the function static. Skip any invocation of ->set_mctrl() if RS485 is enabled. RS485 has no hardware flow control, so the modem control lines are irrelevant and need not be touched. When leaving RS485 mode, reset the modem control lines to the state stored in port->mctrl. That way, UARTs which are muxed between RS485 and RS232 transceivers drive the lines correctly when switched to RS232. (serial8250_do_startup() historically raises the OUT1 modem signal because otherwise interrupts are not signaled on ancient PC UARTs, but I believe that no longer applies to modern, RS485-capable UARTs and is thus safe to be skipped.) imx.c modifies port->mctrl whenever Transmit Enable is asserted and deasserted. Stop it from doing that so port->mctrl reflects the RS232 line state. 8250_omap.c deasserts Transmit Enable on ->runtime_resume() by calling ->set_mctrl(). Because that is now a no-op in RS485 mode, amend the function to call serial8250_em485_stop_tx(). fsl_lpuart.c retrieves and applies the RS485 device tree properties after registering the UART port. Because applying now happens on registration in uart_configure_port(), move retrieval of the properties ahead of uart_add_one_port(). Link: https://lore.kernel.org/all/20220329085050.311408-1-matthias.schiffer@ew.tq-group.com/ Link: https://lore.kernel.org/all/8f538a8903795f22f9acc94a9a31b03c9c4ccacb.camel@ginzinger.com/ Fixes: d3b3404df318 ("serial: Fix incorrect rs485 polarity on uart open") Cc: stable@vger.kernel.org # v4.14+ Reported-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com> Reported-by: Roosen Henri <Henri.Roosen@ginzinger.com> Tested-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Lukas Wunner <lukas@wunner.de> Link: https://lore.kernel.org/r/2de36eba3fbe11278d5002e4e501afe0ceaca039.1663863805.git.lukas@wunner.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-25Merge 7e2cd21e02b3 ("Merge tag 'tty-6.0-rc7' of ↵Greg Kroah-Hartman
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty") into tty-next We need the tty fixes and api additions in this branch. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-22serial: fsl_lpuart: Reset prior to registrationLukas Wunner
Since commit bd5305dcabbc ("tty: serial: fsl_lpuart: do software reset for imx7ulp and imx8qxp"), certain i.MX UARTs are reset after they've already been registered. Register state may thus be clobbered after user space has begun to open and access the UART. Avoid by performing the reset prior to registration. Fixes: bd5305dcabbc ("tty: serial: fsl_lpuart: do software reset for imx7ulp and imx8qxp") Cc: stable@vger.kernel.org # v5.15+ Cc: Fugang Duan <fugang.duan@nxp.com> Cc: Sherry Sun <sherry.sun@nxp.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Lukas Wunner <lukas@wunner.de> Link: https://lore.kernel.org/r/72fb646c1b0b11c989850c55f52f9ff343d1b2fa.1662884345.git.lukas@wunner.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-22tty: serial: fsl_lpuart: disable dma rx/tx use flags in lpuart_dma_shutdownSherry Sun
lpuart_dma_shutdown tears down lpuart dma, but lpuart_flush_buffer can still occur which in turn tries to access dma apis if lpuart_dma_tx_use flag is true. At this point since dma is torn down, these dma apis can abort. Set lpuart_dma_tx_use and the corresponding rx flag lpuart_dma_rx_use to false in lpuart_dma_shutdown so that dmas are not accessed after they are relinquished. Otherwise, when try to kill btattach, kernel may panic. This patch may fix this issue. root@imx8ulpevk:~# btattach -B /dev/ttyLP2 -S 115200 ^C[ 90.182296] Internal error: synchronous external abort: 96000210 [#1] PREEMPT SMP [ 90.189806] Modules linked in: moal(O) mlan(O) [ 90.194258] CPU: 0 PID: 503 Comm: btattach Tainted: G O 5.15.32-06136-g34eecdf2f9e4 #37 [ 90.203554] Hardware name: NXP i.MX8ULP 9X9 EVK (DT) [ 90.208513] pstate: 600000c5 (nZCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 90.215470] pc : fsl_edma3_disable_request+0x8/0x60 [ 90.220358] lr : fsl_edma3_terminate_all+0x34/0x20c [ 90.225237] sp : ffff800013f0bac0 [ 90.228548] x29: ffff800013f0bac0 x28: 0000000000000001 x27: ffff000008404800 [ 90.235681] x26: ffff000008404960 x25: ffff000008404a08 x24: ffff000008404a00 [ 90.242813] x23: ffff000008404a60 x22: 0000000000000002 x21: 0000000000000000 [ 90.249946] x20: ffff800013f0baf8 x19: ffff00000559c800 x18: 0000000000000000 [ 90.257078] x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000 [ 90.264211] x14: 0000000000000003 x13: 0000000000000000 x12: 0000000000000040 [ 90.271344] x11: ffff00000600c248 x10: ffff800013f0bb10 x9 : ffff000057bcb090 [ 90.278477] x8 : fffffc0000241a08 x7 : ffff00000534ee00 x6 : ffff000008404804 [ 90.285609] x5 : 0000000000000000 x4 : 0000000000000000 x3 : ffff0000055b3480 [ 90.292742] x2 : ffff8000135c0000 x1 : ffff00000534ee00 x0 : ffff00000559c800 [ 90.299876] Call trace: [ 90.302321] fsl_edma3_disable_request+0x8/0x60 [ 90.306851] lpuart_flush_buffer+0x40/0x160 [ 90.311037] uart_flush_buffer+0x88/0x120 [ 90.315050] tty_driver_flush_buffer+0x20/0x30 [ 90.319496] hci_uart_flush+0x44/0x90 [ 90.323162] +0x34/0x12c [ 90.327253] tty_ldisc_close+0x38/0x70 [ 90.331005] tty_ldisc_release+0xa8/0x190 [ 90.335018] tty_release_struct+0x24/0x8c [ 90.339022] tty_release+0x3ec/0x4c0 [ 90.342593] __fput+0x70/0x234 [ 90.345652] ____fput+0x14/0x20 [ 90.348790] task_work_run+0x84/0x17c [ 90.352455] do_exit+0x310/0x96c [ 90.355688] do_group_exit+0x3c/0xa0 [ 90.359259] __arm64_sys_exit_group+0x1c/0x20 [ 90.363609] invoke_syscall+0x48/0x114 [ 90.367362] el0_svc_common.constprop.0+0xd4/0xfc [ 90.372068] do_el0_svc+0x2c/0x94 [ 90.375379] el0_svc+0x28/0x80 [ 90.378438] el0t_64_sync_handler+0xa8/0x130 [ 90.382711] el0t_64_sync+0x1a0/0x1a4 [ 90.386376] Code: 17ffffda d503201f d503233f f9409802 (b9400041) [ 90.392467] ---[ end trace 2f60524b4a43f1f6 ]--- [ 90.397073] note: btattach[503] exited with preempt_count 1 [ 90.402636] Fixing recursive fault but reboot is needed! Fixes: 6250cc30c4c4 ("tty: serial: fsl_lpuart: Use scatter/gather DMA for Tx") Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Thara Gopinath <tgopinath@microsoft.com> Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Link: https://lore.kernel.org/r/20220920111703.1532-1-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-05Merge 6.0-rc4 into tty-nextGreg Kroah-Hartman
We need the tty/serial fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-30tty: serial: lpuart: disable flow control while waiting for the transmit ↵Sherry Sun
engine to complete When the user initializes the uart port, and waits for the transmit engine to complete in lpuart32_set_termios(), if the UART TX fifo has dirty data and the UARTMODIR enable the flow control, the TX fifo may never be empty. So here we should disable the flow control first to make sure the transmit engin can complete. Fixes: 380c966c093e ("tty: serial: fsl_lpuart: add 32-bit register interface support") Cc: stable <stable@kernel.org> Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Link: https://lore.kernel.org/r/20220821101527.10066-1-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>