summaryrefslogtreecommitdiff
path: root/drivers/tty
AgeCommit message (Collapse)Author
2021-11-25mxser: remove tty->driver_data NULL checkJiri Slaby
Noone sets tty->driver_data to NULL in the driver, so there is no point to check that in mxser_close(). Remove the check. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20211118073125.12283-8-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25mxser: remove pointless xmit_buf checksJiri Slaby
xmit_buf is supposed to exist in all these functions. I.e. from tty_port_operations::activate() to ::shutdown(). So remove these checks. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20211118073125.12283-7-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25mxser: clean up tx handling in mxser_transmit_chars()Jiri Slaby
The port->icount.tx is handled in a too complicated manner. Instead of remembering the original count and subtracting the new one from it, simply increase tx for each character in the loop. No need for cnt variable then. Change also the "X = X & Y" assignment to simpler "X &= Y". Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20211118073125.12283-6-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25mxser: move MSR read to mxser_check_modem_status()Jiri Slaby
The MSR read is currently performed on both places where mxser_check_modem_status() is called. So move it there to avoid code duplication. Rename the variable to msr while we move it, to actually see what "status" we are testing. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20211118073125.12283-5-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25mxser: keep only !tty test in ISRJiri Slaby
The others are superfluous with tty refcounting in place now. And they are racy in fact: * tty_port_initialized() reports false for a small moment after interrupts are enabled. * closing is 1 while the port is still alive. The queues are flushed later during close anyway. So there is no need for this special handling. Actually, the ISR should not flush the queues. It should behave as every other driver, just queue the chars into tty buffer and go on. But this will be changed later. There is still a lot code depending on having tty in ISR (and not only tty_port). Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20211118073125.12283-4-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25mxser: rename mxser_close_port() to mxser_stop_rx()Jiri Slaby
As it is the only thing it does now. This is one of the future serial_core hooks. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20211118073125.12283-3-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25mxser: remove wait for sent from mxser_close_portJiri Slaby
mxser_close() behaves like this: -> tty_port_close_start() -> tty_wait_until_sent() -> mxser_wait_until_sent() -> mxser_close_port -> wait for TEMT So it is already waited for TEMT through mxser_wait_until_sent() and there is another round of waiting in mxser_close_port(). The latter one is superfluous as nothing could be filled into the output FIFO. Remove the call. This helps unification among drivers (so that all behave the same) and future use of tty_port_close(). Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20211118073125.12283-2-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25serial: sh-sci: Add support to deassert/assert reset lineLad Prabhakar
On RZ/G2L SoC we need to explicitly deassert the reset line for the device to work, use this opportunity to deassert/assert reset line in sh-sci driver. This patch adds support to read the "resets" property (if available) from DT and perform deassert/assert when required. Also, propagate the error to the caller of sci_parse_dt() instead of returning NULL in case of failure. Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com> Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> Link: https://lore.kernel.org/r/20211110232920.19198-4-prabhakar.mahadev-lad.rj@bp.renesas.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25tty: serial, join uport checks in uart_port_shutdown()Jiri Slaby
There are two consequent checks of uport != NULL in uart_port_shutdown(). Join these two under a single block. De-multiline the comments when shuffling with them anyway. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20211118071911.12059-5-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25tty: clean up whitespace in __do_SAK()Jiri Slaby
Remove spaces before the 'i' variable declaration and wrap parameters of group_send_sig_info(). Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20211118071911.12059-4-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25tty: remove tty NULL check from __do_SAK()Jiri Slaby
Both do_SAK_work() and vc_SAK() provide a valid tty to __do_SAK(), so remove the check. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20211118071911.12059-3-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25tty: remove TTY_SOFT_SAK part from __do_SAK()Jiri Slaby
Remove the TTY_SOFT_SAK part. It is never defined, so this is only confusing. It was actually never defined since its introduction in 0.99.14g. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20211118071911.12059-2-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25n_gsm: remove unused parameters from gsm_error()Jiri Slaby
data and flag are unused in gsm_error(), so remove them. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20211118071716.11984-1-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25arm: remove zte zx platform left-overLukas Bulwahn
Commit 89d4f98ae90d ("ARM: remove zte zx platform") missed to remove some definitions for this platform's debug and serial, e.g., code dependent on the config DEBUG_ZTE_ZX. Fortunately, ./scripts/checkkconfigsymbols.py detects this and warns: DEBUG_ZTE_ZX Referencing files: arch/arm/include/debug/pl01x.S Further review by Arnd Bergmann identified even more dead code in the amba serial driver. Remove all this left-over from the zte zx platform. Reviewed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com> Link: https://lore.kernel.org/r/20211102063810.932-1-lukas.bulwahn@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25serial: 8250: replace snprintf in show functions with sysfs_emitJing Yao
coccicheck complains about the use of snprintf() in sysfs show functions: WARNING use scnprintf or sprintf Use sysfs_emit instead of scnprintf or sprintf makes more sense. Reported-by: Zeal Robot <zealci@zte.com.cn> Reviewed-by: Johan Hovold <johan@kernel.org> Signed-off-by: Jing Yao <yao.jing2@zte.com.cn> Link: https://lore.kernel.org/r/20211104114754.30983-1-yao.jing2@zte.com.cn Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25Revert "tty: serial: fsl_lpuart: drop earlycon entry for i.MX8QXP"Alexander Stein
Revert commit b4b844930f27 ("tty: serial: fsl_lpuart: drop earlycon entry for i.MX8QXP"), because this breaks earlycon support on imx8qm/imx8qxp. While it is true that for earlycon there is no difference between i.MX8QXP and i.MX7ULP (for now at least), there are differences regarding clocks and fixups for wakeup support. For that reason it was deemed unacceptable to add the imx7ulp compatible to device tree in order to get earlycon working again. Reviewed-by: Peng Fan <peng.fan@nxp.com> Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com> Link: https://lore.kernel.org/r/20211124073109.805088-1-alexander.stein@ew.tq-group.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25serial: tegra: Change lower tolerance baud rate limit for tegra20 and tegra30Patrik John
The current implementation uses 0 as lower limit for the baud rate tolerance for tegra20 and tegra30 chips which causes isses on UART initialization as soon as baud rate clock is lower than required even when within the standard UART tolerance of +/- 4%. This fix aligns the implementation with the initial commit description of +/- 4% tolerance for tegra chips other than tegra186 and tegra194. Fixes: d781ec21bae6 ("serial: tegra: report clk rate errors") Cc: stable <stable@vger.kernel.org> Signed-off-by: Patrik John <patrik.john@u-blox.com> Link: https://lore.kernel.org/r/sig.19614244f8.20211123132737.88341-1-patrik.john@u-blox.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25serial: liteuart: relax compile-test dependenciesJohan Hovold
The LITEX symbol is neither a build or runtime dependency for the liteuart serial driver. LITEX is selected by the "LiteX SoC Controller" driver, which does a probe-time register-access sanity check and panics if the SoC has not been configured correctly. That driver's Kconfig entry asserts that any LiteX driver using the LiteX register accessors should depend on LITEX, but currently only the serial driver complies. Relax this LITEX "dependency" in order to make it easier to compile test the driver. Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20211117100512.5058-4-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25serial: liteuart: fix minor-number leak on probe errorsJohan Hovold
Make sure to release the allocated minor number before returning on probe errors. Fixes: 1da81e5562fa ("drivers/tty/serial: add LiteUART driver") Cc: stable@vger.kernel.org # 5.11 Cc: Filip Kokosinski <fkokosinski@antmicro.com> Cc: Mateusz Holenko <mholenko@antmicro.com> Reviewed-by: Stafford Horne <shorne@gmail.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20211117100512.5058-3-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25serial: liteuart: fix use-after-free and memleak on unbindJohan Hovold
Deregister the port when unbinding the driver to prevent it from being used after releasing the driver data and leaking memory allocated by serial core. Fixes: 1da81e5562fa ("drivers/tty/serial: add LiteUART driver") Cc: stable@vger.kernel.org # 5.11 Cc: Filip Kokosinski <fkokosinski@antmicro.com> Cc: Mateusz Holenko <mholenko@antmicro.com> Reviewed-by: Stafford Horne <shorne@gmail.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20211117100512.5058-2-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25serial: liteuart: Fix NULL pointer dereference in ->remove()Ilia Sergachev
drvdata has to be set in _probe() - otherwise platform_get_drvdata() causes null pointer dereference BUG in _remove(). Fixes: 1da81e5562fa ("drivers/tty/serial: add LiteUART driver") Cc: stable <stable@vger.kernel.org> Reviewed-by: Johan Hovold <johan@kernel.org> Signed-off-by: Ilia Sergachev <silia@ethz.ch> Link: https://lore.kernel.org/r/20211115224944.23f8c12b@dtkw Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25tty: serial: msm_serial: Deactivate RX DMA for polling supportSven Eckelmann
The CONSOLE_POLLING mode is used for tools like k(g)db. In this kind of setup, it is often sharing a serial device with the normal system console. This is usually no problem because the polling helpers can consume input values directly (when in kgdb context) and the normal Linux handlers can only consume new input values after kgdb switched back. This is not true anymore when RX DMA is enabled for UARTDM controllers. Single input values can no longer be received correctly. Instead following seems to happen: * on 1. input, some old input is read (continuously) * on 2. input, two old inputs are read (continuously) * on 3. input, three old input values are read (continuously) * on 4. input, 4 previous inputs are received This repeats then for each group of 4 input values. This behavior changes slightly depending on what state the controller was when the first input was received. But this makes working with kgdb basically impossible because control messages are always corrupted when kgdboc tries to parse them. RX DMA should therefore be off when CONSOLE_POLLING is enabled to avoid these kind of problems. No such problem was noticed for TX DMA. Fixes: 99693945013a ("tty: serial: msm: Add RX DMA support") Cc: stable@vger.kernel.org Signed-off-by: Sven Eckelmann <sven@narfation.org> Link: https://lore.kernel.org/r/20211113121050.7266-1-sven@narfation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25serial: pl011: Add ACPI SBSA UART match idPierre Gondois
The document 'ACPI for Arm Components 1.0' defines the following _HID mappings: -'Prime cell UART (PL011)': ARMH0011 -'SBSA UART': ARMHB000 Use the sbsa-uart driver when a device is described with the 'ARMHB000' _HID. Note: PL011 devices currently use the sbsa-uart driver instead of the uart-pl011 driver. Indeed, PL011 devices are not bound to a clock in ACPI. It is not possible to change their baudrate. Cc: <stable@vger.kernel.org> Signed-off-by: Pierre Gondois <Pierre.Gondois@arm.com> Link: https://lore.kernel.org/r/20211109172248.19061-1-Pierre.Gondois@arm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-25serial: core: fix transmit-buffer reset and memleakJohan Hovold
Commit 761ed4a94582 ("tty: serial_core: convert uart_close to use tty_port_close") converted serial core to use tty_port_close() but failed to notice that the transmit buffer still needs to be freed on final close. Not freeing the transmit buffer means that the buffer is no longer cleared on next open so that any ioctl() waiting for the buffer to drain might wait indefinitely (e.g. on termios changes) or that stale data can end up being transmitted in case tx is restarted. Furthermore, the buffer of any port that has been opened would leak on driver unbind. Note that the port lock is held when clearing the buffer pointer due to the ldisc race worked around by commit a5ba1d95e46e ("uart: fix race between uart_put_char() and uart_shutdown()"). Also note that the tty-port shutdown() callback is not called for console ports so it is not strictly necessary to free the buffer page after releasing the lock (cf. d72402145ace ("tty/serial: do not free trasnmit buffer page under port lock")). Link: https://lore.kernel.org/r/319321886d97c456203d5c6a576a5480d07c3478.1635781688.git.baruch@tkos.co.il Fixes: 761ed4a94582 ("tty: serial_core: convert uart_close to use tty_port_close") Cc: stable@vger.kernel.org # 4.9 Cc: Rob Herring <robh@kernel.org> Reported-by: Baruch Siach <baruch@tkos.co.il> Tested-by: Baruch Siach <baruch@tkos.co.il> Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20211108085431.12637-1-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-23xen: flag hvc_xen to be not essential for system bootJuergen Gross
The Xen pv console driver is not essential for boot. Set the respective flag. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/20211022064800.14978-4-jgross@suse.com Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2021-11-04Merge tag 'tty-5.16-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 and serial driver updates for 5.16-rc1. Nothing major in here at all, just lots of tiny serial and tty driver updates for various reported things, and some good cleanups. These include: - more good tty api cleanups from Jiri - stm32 serial driver updates - softlockup fix for non-preempt systems under high serial load - rpmsg serial driver update - 8250 drivers updates and fixes - n_gsm line discipline fixes and updates as people are finally starting to use it. All of these have been in linux-next for a while now with no reported issues" * tag 'tty-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (86 commits) tty: Fix extra "not" in TTY_DRIVER_REAL_RAW description serial: cpm_uart: Protect udbg definitions by CONFIG_SERIAL_CPM_CONSOLE tty: rpmsg: Define tty name via constant string literal tty: rpmsg: Add pr_fmt() to prefix messages tty: rpmsg: Use dev_err_probe() in ->probe() tty: rpmsg: Unify variable used to keep an error code tty: rpmsg: Assign returned id to a local variable serial: stm32: push DMA RX data before suspending serial: stm32: terminate / restart DMA transfer at suspend / resume serial: stm32: rework RX dma initialization and release serial: 8250_pci: Remove empty stub pci_quatech_exit() serial: 8250_pci: Replace custom pci_match_id() implementation serial: xilinx_uartps: Fix race condition causing stuck TX serial: sunzilog: Mark sunzilog_putchar() __maybe_unused Revert "tty: hvc: pass DMA capable memory to put_chars()" Revert "virtio-console: remove unnecessary kmemdup()" serial: 8250_pci: Replace dev_*() by pci_*() macros serial: 8250_pci: Get rid of redundant 'else' keyword serial: 8250_pci: Refactor the loop in pci_ite887x_init() tty: add rpmsg driver ...
2021-10-30serial: cpm_uart: Protect udbg definitions by CONFIG_SERIAL_CPM_CONSOLEGeert Uytterhoeven
If CONFIG_CONSOLE_POLL=y, and CONFIG_SERIAL_CPM=m (hence CONFIG_SERIAL_CPM_CONSOLE=n): drivers/tty/serial/cpm_uart/cpm_uart_core.c:1109:12: warning: ‘udbg_cpm_getc’ defined but not used [-Wunused-function] 1109 | static int udbg_cpm_getc(void) | ^~~~~~~~~~~~~ drivers/tty/serial/cpm_uart/cpm_uart_core.c:1095:13: warning: ‘udbg_cpm_putc’ defined but not used [-Wunused-function] 1095 | static void udbg_cpm_putc(char c) | ^~~~~~~~~~~~~ Fix this by making the udbg definitions depend on CONFIG_SERIAL_CPM_CONSOLE, in addition to CONFIG_CONSOLE_POLL. Fixes: a60526097f42eb98 ("tty: serial: cpm_uart: Add udbg support for enabling xmon") Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Link: https://lore.kernel.org/r/20211027075326.3270785-1-geert@linux-m68k.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-26tty: rpmsg: Define tty name via constant string literalAndy Shevchenko
Driver uses already twice the same string literal. Define it in one place, so every user will have this name consistent. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20211025135148.53944-5-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-26tty: rpmsg: Add pr_fmt() to prefix messagesAndy Shevchenko
Make all messages to be prefixed in a unified way. Add pr_fmt() to achieve this. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20211025135148.53944-4-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-26tty: rpmsg: Use dev_err_probe() in ->probe()Andy Shevchenko
It's fine to use dev_err_probe() in ->probe() even if we know it won't be deferred. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20211025135148.53944-3-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-26tty: rpmsg: Unify variable used to keep an error codeAndy Shevchenko
In some ret is used, in the other err. Let's unify it across the driver. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20211025135148.53944-2-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-26tty: rpmsg: Assign returned id to a local variableAndy Shevchenko
Instead of putting garbage in the data structure, assign allocated id or an error code to a temporary variable. This makes code cleaner. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20211025135148.53944-1-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-26serial: stm32: push DMA RX data before suspendingErwan Le Ray
Data may be stored in DMA RX buffer, when suspending. The data needs to be pushed to the upper layer. We can't rely on the timeout IRQ (RTOR) that can't be triggered into low power state. So safely clear DMA request (DMAR), force the DMA reception routines to push RX buffer content, before disabling RX DMA. This way, handover to pio mode is safe. Only call tty_flip_buffer_push() when there is RX data to handle. Move the locking outside of stm32_usart_receive_chars() to prevent a race condition, when disabling DMA request upon suspend / pm_runtime_suspend. Data may be received under IRQ and pushed before stm32_usart_receive_chars() has pushed older data from DMA rx_buf upon suspend. The sequence in suspend routine needs proper locking to avoid this. Signed-off-by: Fabrice Gasnier <fabrice.gasnier@foss.st.com> Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com> Link: https://lore.kernel.org/r/20211025134229.8456-4-erwan.leray@foss.st.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-26serial: stm32: terminate / restart DMA transfer at suspend / resumeErwan Le Ray
DMA prevents the system to suspend when an UART RX wake-up source is using DMA. DMA can't suspend while DMA channels are still active. Terminate DMA transfer at suspend, and restart a new DMA transfer at resume. Create stm32_usart_start_rx_dma_cyclic function to factorize dma RX initialization. Move RX DMA code related to wakeup into stm32_usart_serial_en_wakeup() routine to ease further improvements on wakeup from low power modes. Don't enable/disable wakeup on uninitialized port. There may be data residue in the RX FIFO while suspending. Flush it at suspend time. Receiver timeout interrupt won't trigger later in low power mode, so call stm32_usart_receive_chars() in case there's data to handle. Signed-off-by: Valentin Caron <valentin.caron@foss.st.com> Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com> Link: https://lore.kernel.org/r/20211025134229.8456-3-erwan.leray@foss.st.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-26serial: stm32: rework RX dma initialization and releaseErwan Le Ray
The RX DMA channel is kept active forever (from the probe). That prevents going to low power mode when it is used. This change moves the DMA configuration and enabling procedures to startup routine to allow transition to low power mode. The DMA disabling procedure is implemented in stop_rx routine as this ops has to stop characters reception, and DMA transation in shutdown. Clean useless dma_async_tx_descriptor initialization to NULL value. Signed-off-by: Valentin Caron <valentin.caron@foss.st.com> Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com> Link: https://lore.kernel.org/r/20211025134229.8456-2-erwan.leray@foss.st.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-26serial: 8250_pci: Remove empty stub pci_quatech_exit()Andy Shevchenko
The ->exit() callback is checked for presence anyway, no need to have an empty stub. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20211026133452.61657-2-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-26serial: 8250_pci: Replace custom pci_match_id() implementationAndy Shevchenko
Replace pci_quatech_amcc() with generic pci_match_id(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20211026133452.61657-1-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-26serial: xilinx_uartps: Fix race condition causing stuck TXAnssi Hannula
xilinx_uartps .start_tx() clears TXEMPTY when enabling TXEMPTY to avoid any previous TXEVENT event asserting the UART interrupt. This clear operation is done immediately after filling the TX FIFO. However, if the bytes inserted by cdns_uart_handle_tx() are consumed by the UART before the TXEMPTY is cleared, the clear operation eats the new TXEMPTY event as well, causing cdns_uart_isr() to never receive the TXEMPTY event. If there are bytes still queued in circbuf, TX will get stuck as they will never get transferred to FIFO (unless new bytes are queued to circbuf in which case .start_tx() is called again). While the racy missed TXEMPTY occurs fairly often with short data sequences (e.g. write 1 byte), in those cases circbuf is usually empty so no action on TXEMPTY would have been needed anyway. On the other hand, longer data sequences make the race much more unlikely as UART takes longer to consume the TX FIFO. Therefore it is rare for this race to cause visible issues in general. Fix the race by clearing the TXEMPTY bit in ISR *before* filling the FIFO. The TXEMPTY bit in ISR will only get asserted at the exact moment the TX FIFO *becomes* empty, so clearing the bit before filling FIFO does not cause an extra immediate assertion even if the FIFO is initially empty. This is hard to reproduce directly on a normal system, but inserting e.g. udelay(200) after cdns_uart_handle_tx(port), setting 4000000 baud, and then running "dd if=/dev/zero bs=128 of=/dev/ttyPS0 count=50" reliably reproduces the issue on my ZynqMP test system unless this fix is applied. Fixes: 85baf542d54e ("tty: xuartps: support 64 byte FIFO size") Signed-off-by: Anssi Hannula <anssi.hannula@bitwise.fi> Link: https://lore.kernel.org/r/20211026102741.2910441-1-anssi.hannula@bitwise.fi Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-26serial: sunzilog: Mark sunzilog_putchar() __maybe_unusedGeert Uytterhoeven
If CONSOLE_POLL=n, CONFIG_SERIAL_SUNZILOG_CONSOLE=n, and CONFIG_SERIO=m: drivers/tty/serial/sunzilog.c:1128:13: error: ‘sunzilog_putchar’ defined but not used [-Werror=unused-function] 1128 | static void sunzilog_putchar(struct uart_port *port, int ch) | ^~~~~~~~~~~~~~~~ Fix this by marking sunzilog_putchar() __maybe_unused. Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Link: https://lore.kernel.org/r/20211026080426.2444756-1-geert@linux-m68k.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-26Revert "tty: hvc: pass DMA capable memory to put_chars()"Greg Kroah-Hartman
This reverts commit 0986d7bc5598f5df30e3db777d00e73890c97627. It still has some issues and needs to be dropped at this point in time. Link: https://lore.kernel.org/r/208f7a41-a9fa-630c-cb44-c37c503f3a72@kernel.org Reported-by: Jiri Slaby <jirislaby@kernel.org> Cc: Xianting Tian <xianting.tian@linux.alibaba.com> Cc: Shile Zhang <shile.zhang@linux.alibaba.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-26serial: 8250_pci: Replace dev_*() by pci_*() macrosAndy Shevchenko
PCI subsystem provides convenient shortcut macros for message printing. Use those macros instead of dev_*(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Jiri Slaby <jslaby@kernel.org> Link: https://lore.kernel.org/r/20211022135147.70965-3-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-26serial: 8250_pci: Get rid of redundant 'else' keywordAndy Shevchenko
The 'else' keyword is not needed when previous conditional branch returns to the upper layer. Get rid of redundant 'else' keyword in such cases. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Jiri Slaby <jslaby@kernel.org> Link: https://lore.kernel.org/r/20211022135147.70965-2-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-26serial: 8250_pci: Refactor the loop in pci_ite887x_init()Andy Shevchenko
The loop can be refactored by using ARRAY_SIZE() instead of NULL terminator. This reduces code base and makes it easier to read and understand. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Jiri Slaby <jslaby@kernel.org> Link: https://lore.kernel.org/r/20211022135147.70965-1-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-21tty: add rpmsg driverArnaud Pouliquen
This driver exposes a standard TTY interface on top of the rpmsg framework through a rpmsg service. This driver supports multi-instances, offering a /dev/ttyRPMSGx entry per rpmsg endpoint. Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@foss.st.com> Link: https://lore.kernel.org/r/20211015094701.5732-3-arnaud.pouliquen@foss.st.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-21serial: 8250_dw: drop bogus uartclk optimisationJohan Hovold
The driver was updating the port uartclk before setting the new rate in an attempt to avoid having the clock notifier redundantly update the divisors. The set_termios() callback is however called under the termios semaphore and tty-port mutex so the worker scheduled by the clock notifier will block in serial8250_update_uartclk() until the uartclk and divisors have been updated anyway. Drop the unnecessary swaps and incorrect comment and simply update the uartclk field if the clock-rate change was successful. Tested-by: Serge Semin <fancer.lancer@gmail.com> Reviewed-by: Serge Semin <fancer.lancer@gmail.com> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20211015111422.1027-4-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-21serial: 8250: rename unlock labelsJohan Hovold
Rename a couple of oddly named labels that are used to unlock before returning after what they do (rather than after the context they are used in) to improve readability. Tested-by: Serge Semin <fancer.lancer@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Serge Semin <fancer.lancer@gmail.com> Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20211015111422.1027-3-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-21serial: 8250: fix racy uartclk updateJohan Hovold
Commit 868f3ee6e452 ("serial: 8250: Add 8250 port clock update method") added a hack to support SoCs where the UART reference clock can change behind the back of the driver but failed to add the proper locking. First, make sure to take a reference to the tty struct to avoid dereferencing a NULL pointer if the clock change races with a hangup. Second, the termios semaphore must be held during the update to prevent a racing termios change. Fixes: 868f3ee6e452 ("serial: 8250: Add 8250 port clock update method") Fixes: c8dff3aa8241 ("serial: 8250: Skip uninitialized TTY port baud rate update") Cc: stable@vger.kernel.org # 5.9 Cc: Serge Semin <Sergey.Semin@baikalelectronics.ru> Tested-by: Serge Semin <fancer.lancer@gmail.com> Reviewed-by: Serge Semin <fancer.lancer@gmail.com> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20211015111422.1027-2-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-21serial: stm32: update throttle and unthrottle ops for dma modeErwan Le Ray
Disable DMA request line (if enabled) to switch in PIO mode in throttle ops, so the RX data gets queues into the FIFO. The hardware flow control is triggered when the RX FIFO is full. Switch back to DMA mode (re-enable DMA request line) in unthrottle ops. Hardware flow control is stopped when FIFO is not full anymore. Signed-off-by: Valentin Caron <valentin.caron@foss.st.com> Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com> Link: https://lore.kernel.org/r/20211020150332.10214-4-erwan.leray@foss.st.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-21serial: stm32: rework RX over DMAErwan Le Ray
This patch reworks RX support over DMA to improve reliability: - change dma buffer cyclic configuration by using 2 periods. DMA buffer data are handled by a flip-flop between the 2 periods in order to avoid risk of data loss/corruption - change the size of dma buffer to 4096 to limit overruns - add rx errors management (breaks, parity, framing and overrun). When an error occurs on the uart line, the dma request line is masked at HW level. The SW must 1st clear DMAR (dma request line enable), to handle the error, then re-enable DMAR to recover. So, any correct data is taken from the DMA buffer, before handling the error itself. Then errors are handled from RDR/ISR/FIFO (e.g. in PIO mode). Last, DMA reception is resumed. - add a condition on DMA request line in DMA RX routines in order to switch to PIO mode when no DMA request line is disabled, even if the DMA channel is still enabled. When the UART is wakeup source and is configured to use DMA for RX, any incoming data that wakes up the system isn't correctly received. At data reception, the irq_handler handles the WUF irq, and then the data reception over DMA. As the DMA transfer has been terminated at suspend, and will be restored by resume callback (which has no yet been called by system), the data can't be received. The wake-up data has to be handled in PIO mode while suspend callback has not been called. Signed-off-by: Valentin Caron <valentin.caron@foss.st.com> Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com> Link: https://lore.kernel.org/r/20211020150332.10214-3-erwan.leray@foss.st.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-21serial: stm32: re-introduce an irq flag condition in usart_receive_charsErwan Le Ray
Re-introduce an irq flag condition in usart_receive_chars. This condition has been deleted by commit 75f4e830fa9c ("serial: do not restore interrupt state in sysrq helper"). This code was present to handle threaded case, and has been removed because it is no more needed in this case. Nevertheless an irq safe lock is still needed in some cases, when DMA should be stopped to receive errors or breaks in PIO mode. This patch is a precursor to the complete rework or stm32 serial driver DMA implementation. Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com> Link: https://lore.kernel.org/r/20211020150332.10214-2-erwan.leray@foss.st.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
generated by cgit (git 2.34.1) at 2025-09-11 21:17:00 +0000