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2024-04-27serial: core: Fix missing shutdown and startup for serial base portTony Lindgren3-3/+55
commit 1aa4ad4eb695bac1b0a7ba542a16d6833c9c8dd8 upstream. We are seeing start_tx being called after port shutdown as noted by Jiri. This happens because we are missing the startup and shutdown related functions for the serial base port. Let's fix the issue by adding startup and shutdown functions for the serial base port to block tx flushing for the serial base port when the port is not in use. Fixes: 84a9582fd203 ("serial: core: Start managing serial controllers to enable runtime PM") Cc: stable <stable@kernel.org> Reported-by: Jiri Slaby <jirislaby@kernel.org> Signed-off-by: Tony Lindgren <tony@atomide.com> Link: https://lore.kernel.org/r/20240411055848.38190-1-tony@atomide.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-27serial: core: Clearing the circular buffer before NULLifying itAndy Shevchenko1-0/+1
commit 9cf7ea2eeb745213dc2a04103e426b960e807940 upstream. The circular buffer is NULLified in uart_tty_port_shutdown() under the spin lock. However, the PM or other timer based callbacks may still trigger after this event without knowning that buffer pointer is not valid. Since the serial code is a bit inconsistent in checking the buffer state (some rely on the head-tail positions, some on the buffer pointer), it's better to have both aligned, i.e. buffer pointer to be NULL and head-tail possitions to be the same, meaning it's empty. This will prevent asynchronous calls to dereference NULL pointer as reported recently in 8250 case: BUG: kernel NULL pointer dereference, address: 00000cf5 Workqueue: pm pm_runtime_work EIP: serial8250_tx_chars (drivers/tty/serial/8250/8250_port.c:1809) ... ? serial8250_tx_chars (drivers/tty/serial/8250/8250_port.c:1809) __start_tx (drivers/tty/serial/8250/8250_port.c:1551) serial8250_start_tx (drivers/tty/serial/8250/8250_port.c:1654) serial_port_runtime_suspend (include/linux/serial_core.h:667 drivers/tty/serial/serial_port.c:63) __rpm_callback (drivers/base/power/runtime.c:393) ? serial_port_remove (drivers/tty/serial/serial_port.c:50) rpm_suspend (drivers/base/power/runtime.c:447) The proposed change will prevent ->start_tx() to be called during suspend on shut down port. Fixes: 43066e32227e ("serial: port: Don't suspend if the port is still busy") Cc: stable <stable@kernel.org> Reported-by: kernel test robot <oliver.sang@intel.com> Closes: https://lore.kernel.org/oe-lkp/202404031607.2e92eebe-lkp@intel.com Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20240404150034.41648-1-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-27serial: stm32: Reset .throttled state in .startup()Uwe Kleine-König1-0/+1
commit ea2624b5b829b8f93c0dce25721d835969b34faf upstream. When an UART is opened that still has .throttled set from a previous open, the RX interrupt is enabled but the irq handler doesn't consider it. This easily results in a stuck irq with the effect to occupy the CPU in a tight loop. So reset the throttle state in .startup() to ensure that RX irqs are handled. Fixes: d1ec8a2eabe9 ("serial: stm32: update throttle and unthrottle ops for dma mode") Cc: stable@vger.kernel.org Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Link: https://lore.kernel.org/r/a784f80d3414f7db723b2ec66efc56e1ad666cbf.1713344161.git.u.kleine-koenig@pengutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-27serial: stm32: Return IRQ_NONE in the ISR if no handling happendUwe Kleine-König1-2/+10
commit 13c785323b36b845300b256d0e5963c3727667d7 upstream. If there is a stuck irq that the handler doesn't address, returning IRQ_HANDLED unconditionally makes it impossible for the irq core to detect the problem and disable the irq. So only return IRQ_HANDLED if an event was handled. A stuck irq is still problematic, but with this change at least it only makes the UART nonfunctional instead of occupying the (usually only) CPU by 100% and so stall the whole machine. Fixes: 48a6092fb41f ("serial: stm32-usart: Add STM32 USART Driver") Cc: stable@vger.kernel.org Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Link: https://lore.kernel.org/r/5f92603d0dfd8a5b8014b2b10a902d91e0bb881f.1713344161.git.u.kleine-koenig@pengutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-27serial/pmac_zilog: Remove flawed mitigation for rx irq floodFinn Thain1-14/+0
commit 1be3226445362bfbf461c92a5bcdb1723f2e4907 upstream. The mitigation was intended to stop the irq completely. That may be better than a hard lock-up but it turns out that you get a crash anyway if you're using pmac_zilog as a serial console: ttyPZ0: pmz: rx irq flood ! BUG: spinlock recursion on CPU#0, swapper/0 That's because the pr_err() call in pmz_receive_chars() results in pmz_console_write() attempting to lock a spinlock already locked in pmz_interrupt(). With CONFIG_DEBUG_SPINLOCK=y, this produces a fatal BUG splat. The spinlock in question is the one in struct uart_port. Even when it's not fatal, the serial port rx function ceases to work. Also, the iteration limit doesn't play nicely with QEMU, as can be seen in the bug report linked below. A web search for other reports of the error message "pmz: rx irq flood" didn't produce anything. So I don't think this code is needed any more. Remove it. Cc: Benjamin Herrenschmidt <benh@kernel.crashing.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: Andy Shevchenko <andy.shevchenko@gmail.com> Cc: stable@kernel.org Cc: linux-m68k@lists.linux-m68k.org Link: https://github.com/vivier/qemu-m68k/issues/44 Link: https://lore.kernel.org/all/1078874617.9746.36.camel@gaston/ Acked-by: Michael Ellerman <mpe@ellerman.id.au> Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable <stable@kernel.org> Signed-off-by: Finn Thain <fthain@linux-m68k.org> Link: https://lore.kernel.org/r/e853cf2c762f23101cd2ddec0cc0c2be0e72685f.1712568223.git.fthain@linux-m68k.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-27serial: mxs-auart: add spinlock around changing cts stateEmil Kronborg1-2/+6
commit 54c4ec5f8c471b7c1137a1f769648549c423c026 upstream. The uart_handle_cts_change() function in serial_core expects the caller to hold uport->lock. For example, I have seen the below kernel splat, when the Bluetooth driver is loaded on an i.MX28 board. [ 85.119255] ------------[ cut here ]------------ [ 85.124413] WARNING: CPU: 0 PID: 27 at /drivers/tty/serial/serial_core.c:3453 uart_handle_cts_change+0xb4/0xec [ 85.134694] Modules linked in: hci_uart bluetooth ecdh_generic ecc wlcore_sdio configfs [ 85.143314] CPU: 0 PID: 27 Comm: kworker/u3:0 Not tainted 6.6.3-00021-gd62a2f068f92 #1 [ 85.151396] Hardware name: Freescale MXS (Device Tree) [ 85.156679] Workqueue: hci0 hci_power_on [bluetooth] (...) [ 85.191765] uart_handle_cts_change from mxs_auart_irq_handle+0x380/0x3f4 [ 85.198787] mxs_auart_irq_handle from __handle_irq_event_percpu+0x88/0x210 (...) Cc: stable@vger.kernel.org Fixes: 4d90bb147ef6 ("serial: core: Document and assert lock requirements for irq helpers") Reviewed-by: Frank Li <Frank.Li@nxp.com> Signed-off-by: Emil Kronborg <emil.kronborg@protonmail.com> Link: https://lore.kernel.org/r/20240320121530.11348-1-emil.kronborg@protonmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-03Revert "tty: serial: simplify qcom_geni_serial_send_chunk_fifo()"Douglas Anderson1-4/+6
commit 3d9319c27ceb35fa3d2c8b15508967f3fc7e5b78 upstream. This reverts commit 5c7e105cd156fc9adf5294a83623d7a40c15f9b9. As identified by KASAN, the simplification done by the cleanup patch was not legal. >From tracing through the code, it can be seen that we're transmitting from a 4096-byte circular buffer. We copy anywhere from 1-4 bytes from it each time. The simplification runs into trouble when we get near the end of the circular buffer. For instance, we might start out with xmit->tail = 4094 and we want to transfer 4 bytes. With the code before simplification this was no problem. We'd read buf[4094], buf[4095], buf[0], and buf[1]. With the new code we'll do a memcpy(&buf[4094], 4) which reads 2 bytes past the end of the buffer and then skips transmitting what's at buf[0] and buf[1]. KASAN isn't 100% consistent at reporting this for me, but to be extra confident in the analysis, I added traces of the tail and tx_bytes and then wrote a test program: while true; do echo -n "abcdefghijklmnopqrstuvwxyz0" > /dev/ttyMSM0 sleep .1 done I watched the traces over SSH and saw: qcom_geni_serial_send_chunk_fifo: 4093 4 qcom_geni_serial_send_chunk_fifo: 1 3 Which indicated that one byte should be missing. Sure enough the output that should have been: abcdefghijklmnopqrstuvwxyz0 In one case was actually missing a byte: abcdefghijklmnopqrstuvwyz0 Running "ls -al" on large directories also made the missing bytes obvious since columns didn't line up. While the original code may not be the most elegant, we only talking about copying up to 4 bytes here. Let's just go back to the code that worked. Fixes: 5c7e105cd156 ("tty: serial: simplify qcom_geni_serial_send_chunk_fifo()") Cc: stable <stable@kernel.org> Signed-off-by: Douglas Anderson <dianders@chromium.org> Acked-by: Jiri Slaby <jirislaby@kernel.org> Tested-by: Johan Hovold <johan+linaro@kernel.org> Link: https://lore.kernel.org/r/20240304174952.1.I920a314049b345efd1f69d708e7f74d2213d0b49@changeid Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-03vt: fix unicode buffer corruption when deleting charactersNicolas Pitre1-1/+1
commit 1581dafaf0d34bc9c428a794a22110d7046d186d upstream. This is the same issue that was fixed for the VGA text buffer in commit 39cdb68c64d8 ("vt: fix memory overlapping when deleting chars in the buffer"). The cure is also the same i.e. replace memcpy() with memmove() due to the overlaping buffers. Signed-off-by: Nicolas Pitre <nico@fluxnic.net> Fixes: 81732c3b2fed ("tty vt: Fix line garbage in virtual console on command line edition") Cc: stable <stable@kernel.org> Link: https://lore.kernel.org/r/sn184on2-3p0q-0qrq-0218-895349s4753o@syhkavp.arg Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-03serial: port: Don't suspend if the port is still busyYicong Yang1-1/+24
commit 43066e32227ecde674e8ae1fcdd4a1ede67680c2 upstream. We accidently met the issue that the bash prompt is not shown after the previous command done and until the next input if there's only one CPU (In our issue other CPUs are isolated by isolcpus=). Further analysis shows it's because the port entering runtime suspend even if there's still pending chars in the buffer and the pending chars will only be processed in next device resuming. We are using amba-pl011 and the problematic flow is like below: Bash                                         kworker tty_write()   file_tty_write()     n_tty_write()       uart_write()         __uart_start()           pm_runtime_get() // wakeup waker             queue_work()                                     pm_runtime_work()                                                rpm_resume()                                                 status = RPM_RESUMING                                                 serial_port_runtime_resume()                                                   port->ops->start_tx()                                                     pl011_tx_chars()                                                       uart_write_wakeup()         […]         __uart_start()           pm_runtime_get() < 0 // because runtime status = RPM_RESUMING                                // later data are not commit to the port driver                                                 status = RPM_ACTIVE                                                 rpm_idle() -> rpm_suspend() This patch tries to fix this by checking the port busy before entering runtime suspending. A runtime_suspend callback is added for the port driver. When entering runtime suspend the callback is invoked, if there's still pending chars in the buffer then flush the buffer. Fixes: 84a9582fd203 ("serial: core: Start managing serial controllers to enable runtime PM") Cc: stable <stable@kernel.org> Reviewed-by: Tony Lindgren <tony@atomide.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Yicong Yang <yangyicong@hisilicon.com> Link: https://lore.kernel.org/r/20240226152351.40924-1-yangyicong@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-03tty: serial: fsl_lpuart: avoid idle preamble pending if CTS is enabledSherry Sun1-2/+5
commit 74cb7e0355fae9641f825afa389d3fba3b617714 upstream. 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>
2024-04-03tty: serial: imx: Fix broken RS485Rickard x Andersson1-4/+18
commit 672448ccf9b6a676f96f9352cbf91f4d35f4084a upstream. When about to transmit the function imx_uart_start_tx is called and in some RS485 configurations this function will call imx_uart_stop_rx. The problem is that imx_uart_stop_rx will enable loopback in order to release the RS485 bus, but when loopback is enabled transmitted data will just be looped to RX. This patch fixes the above problem by not enabling loopback when about to transmit. This driver now works well when used for RS485 half duplex master configurations. Fixes: 79d0224f6bf2 ("tty: serial: imx: Handle RS485 DE signal active high") Cc: stable <stable@kernel.org> Signed-off-by: Rickard x Andersson <rickaran@axis.com> Tested-by: Christoph Niedermaier <cniedermaier@dh-electronics.com> Link: https://lore.kernel.org/r/20240221115304.509811-1-rickaran@axis.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-03serial: Lock console when calling into driver before registrationPeter Collingbourne2-6/+12
[ Upstream commit 801410b26a0e8b8a16f7915b2b55c9528b69ca87 ] During the handoff from earlycon to the real console driver, we have two separate drivers operating on the same device concurrently. In the case of the 8250 driver these concurrent accesses cause problems due to the driver's use of banked registers, controlled by LCR.DLAB. It is possible for the setup(), config_port(), pm() and set_mctrl() callbacks to set DLAB, which can cause the earlycon code that intends to access TX to instead access DLL, leading to missed output and corruption on the serial line due to unintended modifications to the baud rate. In particular, for setup() we have: univ8250_console_setup() -> serial8250_console_setup() -> uart_set_options() -> serial8250_set_termios() -> serial8250_do_set_termios() -> serial8250_do_set_divisor() For config_port() we have: serial8250_config_port() -> autoconfig() For pm() we have: serial8250_pm() -> serial8250_do_pm() -> serial8250_set_sleep() For set_mctrl() we have (for some devices): serial8250_set_mctrl() -> omap8250_set_mctrl() -> __omap8250_set_mctrl() To avoid such problems, let's make it so that the console is locked during pre-registration calls to these callbacks, which will prevent the earlycon driver from running concurrently. Remove the partial solution to this problem in the 8250 driver that locked the console only during autoconfig_irq(), as this would result in a deadlock with the new approach. The console continues to be locked during autoconfig_irq() because it can only be called through uart_configure_port(). Although this patch introduces more locking than strictly necessary (and in particular it also locks during the call to rs485_config() which is not affected by this issue as far as I can tell), it follows the principle that it is the responsibility of the generic console code to manage the earlycon handoff by ensuring that earlycon and real console driver code cannot run concurrently, and not the individual drivers. Signed-off-by: Peter Collingbourne <pcc@google.com> Reviewed-by: John Ogness <john.ogness@linutronix.de> Link: https://linux-review.googlesource.com/id/I7cf8124dcebf8618e6b2ee543fa5b25532de55d8 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20240304214350.501253-1-pcc@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-04-03serial: max310x: fix NULL pointer dereference in I2C instantiationHugo Villeneuve1-2/+5
[ Upstream commit 0d27056c24efd3d63a03f3edfbcfc4827086b110 ] When trying to instantiate a max14830 device from userspace: echo max14830 0x60 > /sys/bus/i2c/devices/i2c-2/new_device we get the following error: Unable to handle kernel NULL pointer dereference at virtual address... ... Call trace: max310x_i2c_probe+0x48/0x170 [max310x] i2c_device_probe+0x150/0x2a0 ... Add check for validity of devtype to prevent the error, and abort probe with a meaningful error message. Fixes: 2e1f2d9a9bdb ("serial: max310x: implement I2C support") Cc: stable@vger.kernel.org Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com> Link: https://lore.kernel.org/r/20240118152213.2644269-2-hugo@hugovil.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-27serial: 8250_exar: Don't remove GPIO device on suspendAndy Shevchenko1-4/+1
[ Upstream commit 73b5a5c00be39e23b194bad10e1ea8bb73eee176 ] It seems a copy&paste mistake that suspend callback removes the GPIO device. There is no counterpart of this action, means once suspended there is no more GPIO device available untile full unbind-bind cycle is performed. Remove suspicious GPIO device removal in suspend. Fixes: d0aeaa83f0b0 ("serial: exar: split out the exar code from 8250_pci") Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20240219150627.2101198-2-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-27tty: serial: samsung: fix tx_empty() to return TIOCSER_TEMTTudor Ambarus1-3/+2
[ Upstream commit 314c2b399288f0058a8c5b6683292cbde5f1531b ] The core expects for tx_empty() either TIOCSER_TEMT when the tx is empty or 0 otherwise. s3c24xx_serial_txempty_nofifo() might return 0x4, and at least uart_get_lsr_info() tries to clear exactly TIOCSER_TEMT (BIT(1)). Fix tx_empty() to return TIOCSER_TEMT. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org> Reviewed-by: Sam Protsenko <semen.protsenko@linaro.org> Link: https://lore.kernel.org/r/20240119104526.1221243-2-tudor.ambarus@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-27serial: max310x: fix syntax error in IRQ error messageHugo Villeneuve1-1/+1
[ Upstream commit 8ede8c6f474255b2213cccd7997b993272a8e2f9 ] Replace g with q. Helpful when grepping thru source code or logs for "request" keyword. Fixes: f65444187a66 ("serial: New serial driver MAX310X") Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com> Link: https://lore.kernel.org/r/20240118152213.2644269-6-hugo@hugovil.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-27tty: vt: fix 20 vs 0x20 typo in EScsiignoreJiri Slaby (SUSE)1-1/+1
[ Upstream commit 0e6a92f67c8a94707f7bb27ac29e2bdf3e7c167d ] The if (c >= 20 && c <= 0x3f) test added in commit 7a99565f8732 is wrong. 20 is DC4 in ascii and it makes no sense to consider that as the bottom limit. Instead, it should be 0x20 as in the other test in the commit above. This is supposed to NOT change anything as we handle interesting 20-0x20 asciis far before this if. So for sakeness, change to 0x20 (which is SPACE). Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org> Fixes: 7a99565f8732 ("vt: ignore csi sequences with intermediate characters.") Cc: Martin Hostettler <textshell@uchuujin.de> Link: https://lore.kernel.org/all/ZaP45QY2WEsDqoxg@neutronstar.dyndns.org/ Tested-by: Helge Deller <deller@gmx.de> # parisc STI console Link: https://lore.kernel.org/r/20240122110401.7289-4-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-01serial: amba-pl011: Fix DMA transmission in RS485 modeLino Sanfilippo1-30/+30
commit 3b69e32e151bc4a4e3c785cbdb1f918d5ee337ed upstream. 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>
2024-03-01serial: stm32: do not always set SER_RS485_RX_DURING_TX if RS485 is enabledLino Sanfilippo1-1/+3
commit f418ae73311deb901c0110b08d1bbafc20c1820e upstream. Before commit 07c30ea5861f ("serial: Do not hold the port lock when setting rx-during-tx GPIO") the SER_RS485_RX_DURING_TX flag was only set if the rx-during-tx mode was not controlled by a GPIO. Now the flag is set unconditionally when RS485 is enabled. This results in an incorrect setting if the rx-during-tx GPIO is not asserted. Fix this by setting the flag only if the rx-during-tx mode is not controlled by a GPIO and thus restore the correct behaviour. Cc: stable@vger.kernel.org # 6.6+ Fixes: 07c30ea5861f ("serial: Do not hold the port lock when setting rx-during-tx GPIO") Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com> Link: https://lore.kernel.org/r/20240216224709.9928-1-l.sanfilippo@kunbus.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-23serial: mxs-auart: fix txJiri Slaby (SUSE)1-1/+4
commit 7be50f2e8f20fc2299069b28dea59a28e3abe20a upstream. Emil reports: After updating Linux on an i.MX28 board, serial communication over AUART broke. When I TX from the board and measure on the TX pin, it seems like the HW fifo is not emptied before the transmission is stopped. MXS performs weird things with stop_tx(). The driver makes it conditional on uart_tx_stopped(). So the driver needs special handling. Pass the brand new UART_TX_NOSTOP to uart_port_tx_flags() and handle the stop on its own. Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org> Reported-by: Emil Kronborg <emil.kronborg@protonmail.com> Cc: stable <stable@kernel.org> Fixes: 2d141e683e9a ("tty: serial: use uart_port_tx() helper") Closes: https://lore.kernel.org/all/miwgbnvy3hjpnricubg76ytpn7xoceehwahupy25bubbduu23s@om2lptpa26xw/ Tested-by: Stefan Wahren <wahrenst@gmx.net> Tested-by: Emil Kronborg <emil.kronborg@protonmail.com> Link: https://lore.kernel.org/r/20240201105557.28043-2-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-23serial: max310x: prevent infinite while() loop in port startupHugo Villeneuve1-2/+18
commit b35f8dbbce818b02c730dc85133dc7754266e084 upstream. If there is a problem after resetting a port, the do/while() loop that checks the default value of DIVLSB register may run forever and spam the I2C bus. Add a delay before each read of DIVLSB, and a maximum number of tries to prevent that situation from happening. Also fail probe if port reset is unsuccessful. Fixes: 10d8b34a4217 ("serial: max310x: Driver rework") Cc: stable@vger.kernel.org Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com> Link: https://lore.kernel.org/r/20240116213001.3691629-5-hugo@hugovil.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-23serial: max310x: fail probe if clock crystal is unstableHugo Villeneuve1-3/+9
commit 8afa6c6decea37e7cb473d2c60473f37f46cea35 upstream. A stable clock is really required in order to use this UART, so log an error message and bail out if the chip reports that the clock is not stable. Fixes: 4cf9a888fd3c ("serial: max310x: Check the clock readiness") Cc: stable@vger.kernel.org Suggested-by: Jan Kundrát <jan.kundrat@cesnet.cz> Link: https://www.spinics.net/lists/linux-serial/msg35773.html Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com> Link: https://lore.kernel.org/r/20240116213001.3691629-4-hugo@hugovil.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-23serial: max310x: improve crystal stable clock detectionHugo Villeneuve1-5/+16
commit 93cd256ab224c2519e7c4e5f58bb4f1ac2bf0965 upstream. Some people are seeing a warning similar to this when using a crystal: max310x 11-006c: clock is not stable yet The datasheet doesn't mention the maximum time to wait for the clock to be stable when using a crystal, and it seems that the 10ms delay in the driver is not always sufficient. Jan Kundrát reported that it took three tries (each separated by 10ms) to get a stable clock. Modify behavior to check stable clock ready bit multiple times (20), and waiting 10ms between each try. Note: the first draft of the driver originally used a 50ms delay, without checking the clock stable bit. Then a loop with 1000 retries was implemented, each time reading the clock stable bit. Fixes: 4cf9a888fd3c ("serial: max310x: Check the clock readiness") Cc: stable@vger.kernel.org Suggested-by: Jan Kundrát <jan.kundrat@cesnet.cz> Link: https://www.spinics.net/lists/linux-serial/msg35773.html Link: https://lore.kernel.org/all/20240110174015.6f20195fde08e5c9e64e5675@hugovil.com/raw Link: https://github.com/boundarydevices/linux/commit/e5dfe3e4a751392515d78051973190301a37ca9a Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com> Link: https://lore.kernel.org/r/20240116213001.3691629-3-hugo@hugovil.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-23serial: max310x: set default value when reading clock ready bitHugo Villeneuve1-1/+1
commit 0419373333c2f2024966d36261fd82a453281e80 upstream. If regmap_read() returns a non-zero value, the 'val' variable can be left uninitialized. Clear it before calling regmap_read() to make sure we properly detect the clock ready bit. Fixes: 4cf9a888fd3c ("serial: max310x: Check the clock readiness") Cc: stable@vger.kernel.org Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com> Link: https://lore.kernel.org/r/20240116213001.3691629-2-hugo@hugovil.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-05tty: allow TIOCSLCKTRMIOS with CAP_CHECKPOINT_RESTOREAdrian Reber1-2/+2
[ Upstream commit e0f25b8992345aa5f113da2815f5add98738c611 ] The capability CAP_CHECKPOINT_RESTORE was introduced to allow non-root users to checkpoint and restore processes as non-root with CRIU. This change extends CAP_CHECKPOINT_RESTORE to enable the CRIU option '--shell-job' as non-root. CRIU's man-page describes the '--shell-job' option like this: Allow one to dump shell jobs. This implies the restored task will inherit session and process group ID from the criu itself. This option also allows to migrate a single external tty connection, to migrate applications like top. TIOCSLCKTRMIOS can only be done if the process has CAP_SYS_ADMIN and this change extends it to CAP_SYS_ADMIN or CAP_CHECKPOINT_RESTORE. With this change it is possible to checkpoint and restore processes which have a tty connection as non-root if CAP_CHECKPOINT_RESTORE is set. Acked-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Adrian Reber <areber@redhat.com> Acked-by: Andrei Vagin <avagin@gmail.com> Link: https://lore.kernel.org/r/20231208143656.1019-1-areber@redhat.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-02-01serial: sc16is7xx: fix unconditional activation of THRI interruptHugo Villeneuve1-5/+2
[ Upstream commit 9915753037eba7135b209fef4f2afeca841af816 ] Commit cc4c1d05eb10 ("sc16is7xx: Properly resume TX after stop") changed behavior to unconditionnaly set the THRI interrupt in sc16is7xx_tx_proc(). For example when sending a 65 bytes message, and assuming the Tx FIFO is initially empty, sc16is7xx_handle_tx() will write the first 64 bytes of the message to the FIFO and sc16is7xx_tx_proc() will then activate THRI. When the THRI IRQ is fired, the driver will write the remaining byte of the message to the FIFO, and disable THRI by calling sc16is7xx_stop_tx(). When sending a 2 bytes message, sc16is7xx_handle_tx() will write the 2 bytes of the message to the FIFO and call sc16is7xx_stop_tx(), disabling THRI. After sc16is7xx_handle_tx() exits, control returns to sc16is7xx_tx_proc() which will unconditionally set THRI. When the THRI IRQ is fired, the driver simply acknowledges the interrupt and does nothing more, since all the data has already been written to the FIFO. This results in 2 register writes and 4 register reads all for nothing and taking precious cycles from the I2C/SPI bus. Fix this by enabling the THRI interrupt only when we fill the Tx FIFO to its maximum capacity and there are remaining bytes to send in the message. Fixes: cc4c1d05eb10 ("sc16is7xx: Properly resume TX after stop") Cc: <stable@vger.kernel.org> Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com> Link: https://lore.kernel.org/r/20231211171353.2901416-7-hugo@hugovil.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-02-01serial: sc16is7xx: Use port lock wrappersThomas Gleixner1-20/+20
[ Upstream commit b465848be8a652e2c5fefe102661fb660cff8497 ] 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/20230914183831.587273-56-john.ogness@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Stable-dep-of: 9915753037eb ("serial: sc16is7xx: fix unconditional activation of THRI interrupt") Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-02-01serial: Do not hold the port lock when setting rx-during-tx GPIOLino Sanfilippo3-12/+26
commit 07c30ea5861fb26a77dade8cdc787252f6122fb1 upstream. Both the imx and stm32 driver set the rx-during-tx GPIO in rs485_config(). Since this function is called with the port lock held, this can be a problem in case that setting the GPIO line can sleep (e.g. if a GPIO expander is used which is connected via SPI or I2C). Avoid this issue by moving the GPIO setting outside of the port lock into the serial core and thus making it a generic feature. Also with commit c54d48543689 ("serial: stm32: Add support for rs485 RX_DURING_TX output GPIO") the SER_RS485_RX_DURING_TX flag is only set if a rx-during-tx GPIO is _not_ available, which is wrong. Fix this, too. Furthermore reset old GPIO settings in case that changing the RS485 configuration failed. Fixes: c54d48543689 ("serial: stm32: Add support for rs485 RX_DURING_TX output GPIO") Fixes: ca530cfa968c ("serial: imx: Add support for RS485 RX_DURING_TX output GPIO") Cc: Shawn Guo <shawnguo@kernel.org> Cc: Sascha Hauer <s.hauer@pengutronix.de> Cc: <stable@vger.kernel.org> Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com> Link: https://lore.kernel.org/r/20240103061818.564-2-l.sanfilippo@kunbus.com Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-01serial: sc16is7xx: improve do/while loop in sc16is7xx_irq()Hugo Villeneuve1-5/+6
commit d5078509c8b06c5c472a60232815e41af81c6446 upstream. Simplify and improve readability by replacing while(1) loop with do {} while, and by using the keep_polling variable as the exit condition, making it more explicit. Fixes: 834449872105 ("sc16is7xx: Fix for multi-channel stall") Cc: <stable@vger.kernel.org> Suggested-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com> Link: https://lore.kernel.org/r/20231221231823.2327894-6-hugo@hugovil.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-01serial: sc16is7xx: remove obsolete loop in sc16is7xx_port_irq()Hugo Villeneuve1-44/+41
commit ed647256e8f226241ecff7baaecdb8632ffc7ec1 upstream. Commit 834449872105 ("sc16is7xx: Fix for multi-channel stall") changed sc16is7xx_port_irq() from looping multiple times when there was still interrupts to serve. It simply changed the do {} while(1) loop to a do {} while(0) loop, which makes the loop itself now obsolete. Clean the code by removing this obsolete do {} while(0) loop. Fixes: 834449872105 ("sc16is7xx: Fix for multi-channel stall") Cc: <stable@vger.kernel.org> Suggested-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com> Link: https://lore.kernel.org/r/20231221231823.2327894-5-hugo@hugovil.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-01serial: sc16is7xx: fix invalid sc16is7xx_lines bitfield in case of probe errorHugo Villeneuve1-26/+18
commit 8a1060ce974919f2a79807527ad82ac39336eda2 upstream. If an error occurs during probing, the sc16is7xx_lines bitfield may be left in a state that doesn't represent the correct state of lines allocation. For example, in a system with two SC16 devices, if an error occurs only during probing of channel (port) B of the second device, sc16is7xx_lines final state will be 00001011b instead of the expected 00000011b. This is caused in part because of the "i--" in the for/loop located in the out_ports: error path. Fix this by checking the return value of uart_add_one_port() and set line allocation bit only if this was successful. This allows the refactor of the obfuscated for(i--...) loop in the error path, and properly call uart_remove_one_port() only when needed, and properly unset line allocation bits. Also use same mechanism in remove() when calling uart_remove_one_port(). Fixes: c64349722d14 ("sc16is7xx: support multiple devices") Cc: <stable@vger.kernel.org> Cc: Yury Norov <yury.norov@gmail.com> Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com> Link: https://lore.kernel.org/r/20231221231823.2327894-2-hugo@hugovil.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-01serial: sc16is7xx: convert from _raw_ to _noinc_ regmap functions for FIFOHugo Villeneuve1-6/+11
commit dbf4ab821804df071c8b566d9813083125e6d97b upstream. The SC16IS7XX IC supports a burst mode to access the FIFOs where the initial register address is sent ($00), followed by all the FIFO data without having to resend the register address each time. In this mode, the IC doesn't increment the register address for each R/W byte. The regmap_raw_read() and regmap_raw_write() are functions which can perform IO over multiple registers. They are currently used to read/write from/to the FIFO, and although they operate correctly in this burst mode on the SPI bus, they would corrupt the regmap cache if it was not disabled manually. The reason is that when the R/W size is more than 1 byte, these functions assume that the register address is incremented and handle the cache accordingly. Convert FIFO R/W functions to use the regmap _noinc_ versions in order to remove the manual cache control which was a workaround when using the _raw_ versions. FIFO registers are properly declared as volatile so cache will not be used/updated for FIFO accesses. Fixes: dfeae619d781 ("serial: sc16is7xx") Cc: <stable@vger.kernel.org> Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com> Link: https://lore.kernel.org/r/20231211171353.2901416-6-hugo@hugovil.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-01serial: sc16is7xx: change EFR lock to operate on each channelsHugo Villeneuve1-23/+26
commit 4409df5866b7ff7686ba27e449ca97a92ee063c9 upstream. Now that the driver has been converted to use one regmap per port, change efr locking to operate on a channel basis instead of on the whole IC. Fixes: 3837a0379533 ("serial: sc16is7xx: improve regmap debugfs by using one regmap per port") Cc: <stable@vger.kernel.org> # 6.1.x: 3837a03 serial: sc16is7xx: improve regmap debugfs by using one regmap per port Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com> Link: https://lore.kernel.org/r/20231211171353.2901416-5-hugo@hugovil.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-01serial: sc16is7xx: remove unused line structure memberHugo Villeneuve1-2/+0
commit 41a308cbedb2a68a6831f0f2e992e296c4b8aff0 upstream. Now that the driver has been converted to use one regmap per port, the line structure member is no longer used, so remove it. Fixes: 3837a0379533 ("serial: sc16is7xx: improve regmap debugfs by using one regmap per port") Cc: <stable@vger.kernel.org> Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com> Link: https://lore.kernel.org/r/20231211171353.2901416-4-hugo@hugovil.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-01serial: sc16is7xx: remove global regmap from struct sc16is7xx_portHugo Villeneuve1-6/+9
commit f6959c5217bd799bcb770b95d3c09b3244e175c6 upstream. Remove global struct regmap so that it is more obvious that this regmap is to be used only in the probe function. Also add a comment to that effect in probe function. Fixes: 3837a0379533 ("serial: sc16is7xx: improve regmap debugfs by using one regmap per port") Cc: <stable@vger.kernel.org> Suggested-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com> Link: https://lore.kernel.org/r/20231211171353.2901416-3-hugo@hugovil.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-01serial: sc16is7xx: remove wasteful static buffer in sc16is7xx_regmap_name()Hugo Villeneuve1-6/+8
commit 6bcab3c8acc88e265c570dea969fd04f137c8a4c upstream. Using a static buffer inside sc16is7xx_regmap_name() was a convenient and simple way to set the regmap name without having to allocate and free a buffer each time it is called. The drawback is that the static buffer wastes memory for nothing once regmap is fully initialized. Remove static buffer and use constant strings instead. This also avoids a truncation warning when using "%d" or "%u" in snprintf which was flagged by kernel test robot. Fixes: 3837a0379533 ("serial: sc16is7xx: improve regmap debugfs by using one regmap per port") Cc: <stable@vger.kernel.org> # 6.1.x: 3837a03 serial: sc16is7xx: improve regmap debugfs by using one regmap per port Suggested-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com> Link: https://lore.kernel.org/r/20231211171353.2901416-2-hugo@hugovil.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-01serial: sc16is7xx: improve regmap debugfs by using one regmap per portHugo Villeneuve1-62/+81
commit 3837a0379533aabb9e4483677077479f7c6aa910 upstream. With this current driver regmap implementation, it is hard to make sense of the register addresses displayed using the regmap debugfs interface, because they do not correspond to the actual register addresses documented in the datasheet. For example, register 1 is displayed as registers 04 thru 07: $ cat /sys/kernel/debug/regmap/spi0.0/registers 04: 10 -> Port 0, register offset 1 05: 10 -> Port 1, register offset 1 06: 00 -> Port 2, register offset 1 -> invalid 07: 00 -> port 3, register offset 1 -> invalid ... The reason is that bits 0 and 1 of the register address correspond to the channel (port) bits, so the register address itself starts at bit 2, and we must 'mentally' shift each register address by 2 bits to get its real address/offset. Also, only channels 0 and 1 are supported by the chip, so channel mask combinations of 10b and 11b are invalid, and the display of these registers is useless. This patch adds a separate regmap configuration for each port, similar to what is done in the max310x driver, so that register addresses displayed match the register addresses in the chip datasheet. Also, each port now has its own debugfs entry. Example with new regmap implementation: $ cat /sys/kernel/debug/regmap/spi0.0-port0/registers 1: 10 2: 01 3: 00 ... $ cat /sys/kernel/debug/regmap/spi0.0-port1/registers 1: 10 2: 01 3: 00 As an added bonus, this also simplifies some operations (read/write/modify) because it is no longer necessary to manually shift register addresses. Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com> Link: https://lore.kernel.org/r/20231030211447.974779-1-hugo@hugovil.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-01serial: core: set missing supported flag for RX during TX GPIOLino Sanfilippo1-0/+2
[ Upstream commit 1a33e33ca0e80d485458410f149265cdc0178cfa ] If the RS485 feature RX-during-TX is supported by means of a GPIO set the according supported flag. Otherwise setting this feature from userspace may not be possible, since in uart_sanitize_serial_rs485() the passed RS485 configuration is matched against the supported features and unsupported settings are thereby removed and thus take no effect. Cc: <stable@vger.kernel.org> Fixes: 163f080eb717 ("serial: core: Add option to output RS485 RX_DURING_TX state via GPIO") Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com> Link: https://lore.kernel.org/r/20240103061818.564-3-l.sanfilippo@kunbus.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-02-01serial: core: Simplify uart_get_rs485_mode()Andy Shevchenko1-18/+12
[ Upstream commit 7cda0b9eb6eb9e761f452e2ef4e81eca20b19938 ] Simplify uart_get_rs485_mode() by using temporary variable for the GPIO descriptor. With that, use proper type for the flags of the GPIO descriptor. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20231003142346.3072929-1-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Stable-dep-of: 1a33e33ca0e8 ("serial: core: set missing supported flag for RX during TX GPIO") Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-26serial: apbuart: fix console prompt on qemuSam Ravnborg1-1/+1
[ Upstream commit c6dcd8050fb7c2efec6946ae9c49bc186b0a7475 ] When using a leon kernel with qemu there where no console prompt. The root cause is the handling of the fifo size in the tx part of the apbuart driver. The qemu uart driver only have a very rudimentary status handling and do not report the number of chars queued in the tx fifo in the status register. So the driver ends up with a fifo size of 1. In the tx path the fifo size is divided by 2 - resulting in a fifo size of zero. The original implementation would always try to send one char, but after the introduction of uart_port_tx_limited() the fifo size is respected even for the first char. There seems to be no good reason to divide the fifo size with two - so remove this. It looks like something copied from the original amba driver. With qemu we now have a minimum fifo size of one char, so we show the prompt. Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Fixes: d11cc8c3c4b6 ("tty: serial: use uart_port_tx_limited()") Cc: Andreas Larsson <andreas@gaisler.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jirislaby@kernel.org> Cc: <linux-serial@vger.kernel.org> Cc: <sparclinux@vger.kernel.org> Link: https://lore.kernel.org/r/20231226121607.GA2622970@ravnborg.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-26serial: imx: Correct clock error message in function probe()Christoph Niedermaier1-1/+1
[ Upstream commit 3e189470cad27d41a3a9dc02649f965b7ed1c90f ] Correct the clock error message by changing the clock name. Fixes: 1e512d45332b ("serial: imx: add error messages when .probe fails") Signed-off-by: Christoph Niedermaier <cniedermaier@dh-electronics.com> Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Link: https://lore.kernel.org/r/20231224093209.2612-1-cniedermaier@dh-electronics.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-26usb: cdc-acm: return correct error code on unsupported breakOliver Neukum1-0/+3
[ Upstream commit 66aad7d8d3ec5a3a8ec2023841bcec2ded5f65c9 ] In ACM support for sending breaks to devices is optional. If a device says that it doenot support sending breaks, the host must respect that. Given the number of optional features providing tty operations for each combination is not practical and errors need to be returned dynamically if unsupported features are requested. In case a device does not support break, we want the tty layer to treat that like it treats drivers that statically cannot support sending a break. It ignores the inability and does nothing. This patch uses EOPNOTSUPP to indicate that. Signed-off-by: Oliver Neukum <oneukum@suse.com> Fixes: 9e98966c7bb94 ("tty: rework break handling") Link: https://lore.kernel.org/r/20231207132639.18250-1-oneukum@suse.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-26tty: use 'if' in send_break() instead of 'goto'Jiri Slaby (SUSE)1-5/+4
[ Upstream commit 24f2cd019946fc2e88e632d2e24a34c2cc3f2be4 ] Now, the "jumped-over" code is simple enough to be put inside an 'if'. Do so to make it 'goto'-less. Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org> Link: https://lore.kernel.org/r/20230919085156.1578-16-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Stable-dep-of: 66aad7d8d3ec ("usb: cdc-acm: return correct error code on unsupported break") Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-26tty: don't check for signal_pending() in send_break()Jiri Slaby (SUSE)1-2/+1
[ Upstream commit fd99392b643b824813df2edbaebe26a2136d31e6 ] msleep_interruptible() will check on its own. So no need to do the check in send_break() before calling the above. Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org> Link: https://lore.kernel.org/r/20230919085156.1578-15-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Stable-dep-of: 66aad7d8d3ec ("usb: cdc-acm: return correct error code on unsupported break") Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-26tty: early return from send_break() on TTY_DRIVER_HARDWARE_BREAKJiri Slaby (SUSE)1-15/+17
[ Upstream commit 66619686d187b4a6395316b7f39881e945dce4bc ] If the driver sets TTY_DRIVER_HARDWARE_BREAK, we leave ops->break_ctl() to the driver and return from send_break(). But we do it using a local variable and keep the code flowing through the end of the function. Instead, do 'return' immediately with the ops->break_ctl()'s return value. This way, we don't have to stuff the 'else' branch of the 'if' with the software break handling. And we can re-indent the function too. Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org> Link: https://lore.kernel.org/r/20230919085156.1578-14-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Stable-dep-of: 66aad7d8d3ec ("usb: cdc-acm: return correct error code on unsupported break") Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-26serial: imx: fix tx statemachine deadlockPaul Geurts1-2/+2
[ Upstream commit 78d60dae9a0c9f09aa3d6477c94047df2fe6f7b0 ] When using the serial port as RS485 port, the tx statemachine is used to control the RTS pin to drive the RS485 transceiver TX_EN pin. When the TTY port is closed in the middle of a transmission (for instance during userland application crash), imx_uart_shutdown disables the interface and disables the Transmission Complete interrupt. afer that, imx_uart_stop_tx bails on an incomplete transmission, to be retriggered by the TC interrupt. This interrupt is disabled and therefore the tx statemachine never transitions out of SEND. The statemachine is in deadlock now, and the TX_EN remains low, making the interface useless. imx_uart_stop_tx now checks for incomplete transmission AND whether TC interrupts are enabled before bailing to be retriggered. This makes sure the state machine handling is reached, and is properly set to WAIT_AFTER_SEND. Fixes: cb1a60923609 ("serial: imx: implement rts delaying for rs485") Signed-off-by: Paul Geurts <paul_geurts@live.nl> Tested-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk> Tested-by: Eberhard Stoll <eberhard.stoll@gmx.de> Link: https://lore.kernel.org/r/AM0PR09MB26758F651BC1B742EB45775995B8A@AM0PR09MB2675.eurprd09.prod.outlook.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-26serial: 8250: omap: Don't skip resource freeing if ↵Uwe Kleine-König1-1/+1
pm_runtime_resume_and_get() failed [ Upstream commit ad90d0358bd3b4554f243a425168fc7cebe7d04e ] Returning an error code from .remove() makes the driver core emit the little helpful error message: remove callback returned a non-zero value. This will be ignored. and then remove the device anyhow. So all resources that were not freed are leaked in this case. Skipping serial8250_unregister_port() has the potential to keep enough of the UART around to trigger a use-after-free. So replace the error return (and with it the little helpful error message) by a more useful error message and continue to cleanup. Fixes: e3f0c638f428 ("serial: 8250: omap: Fix unpaired pm_runtime_put_sync() in omap8250_remove()") Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Reviewed-by: Tony Lindgren <tony@atomide.com> Link: https://lore.kernel.org/r/20231110152927.70601-2-u.kleine-koenig@pengutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-26serial: sc16is7xx: set safe default SPI clock frequencyHugo Villeneuve1-1/+2
commit 3ef79cd1412236d884ab0c46b4d1921380807b48 upstream. 15 MHz is supported only by 76x variants. If the SPI clock frequency is not specified, use a safe default clock value of 4 MHz that is supported by all variants. Also use HZ_PER_MHZ macro to improve readability. Fixes: 2c837a8a8f9f ("sc16is7xx: spi interface is added") Cc: <stable@vger.kernel.org> Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com> Link: https://lore.kernel.org/r/20231221231823.2327894-4-hugo@hugovil.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-26serial: sc16is7xx: add check for unsupported SPI modes during probeHugo Villeneuve1-1/+4
commit 6d710b769c1f5f0d55c9ad9bb49b7dce009ec103 upstream. The original comment is confusing because it implies that variants other than the SC16IS762 supports other SPI modes beside SPI_MODE_0. Extract from datasheet: The SC16IS762 differs from the SC16IS752 in that it supports SPI clock speeds up to 15 Mbit/s instead of the 4 Mbit/s supported by the SC16IS752... In all other aspects, the SC16IS762 is functionally and electrically the same as the SC16IS752. The same is also true of the SC16IS760 variant versus the SC16IS740 and SC16IS750 variants. For all variants, only SPI mode 0 is supported. Change comment and abort probing if the specified SPI mode is not SPI_MODE_0. Fixes: 2c837a8a8f9f ("sc16is7xx: spi interface is added") Cc: <stable@vger.kernel.org> Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com> Link: https://lore.kernel.org/r/20231221231823.2327894-3-hugo@hugovil.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-26serial: omap: do not override settings for RS485 supportLino Sanfilippo1-13/+14
commit 51f93776b84dee23e44a7be880736669a01cec2b upstream. The drivers RS485 support is deactivated if there is no RTS GPIO available. This is done by nullifying the ports rs485_supported struct. After that however the settings in serial_omap_rs485_supported are assigned to the same structure unconditionally, which results in an unintended reactivation of RS485 support. Fix this by moving the assignment to the beginning of serial_omap_probe_rs485() and thus before uart_get_rs485_mode() gets called. Also replace the assignment of rs485_config() to have the complete RS485 setup in one function. Fixes: e2752ae3cfc9 ("serial: omap: Disallow RS-485 if rts-gpio is not specified") Cc: <stable@vger.kernel.org> Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20240103061818.564-7-l.sanfilippo@kunbus.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>