summaryrefslogtreecommitdiff
path: root/drivers/tty/serial
AgeCommit message (Collapse)AuthorFilesLines
2021-04-22serial: ar933x: drop low-latency workaroundJohan Hovold1-2/+0
Commit b16c8e3eed12 ("tty: serial: ar933x: drop uart_port->lock before calling tty_flip_buffer_push()") claimed to address a locking issue but only provided a dubious lockdep splat from an unrelated driver, which in the end turned out to be due a broken local change carried by the author. Unfortunately these patches were merged before the issue had been analysed properly so the commit messages makes no sense whatsoever. The real issue was first seen on RT which at the time effectively always set the low_latency flag for all serial drivers by patching tty_flip_buffer_push(). This in turn revealed that many drivers did not handle the infamous low_latency behaviour which meant that data was pushed immediately to the line discipline instead of being deferred to a work queue. Since commit a9c3f68f3cd8 ("tty: Fix low_latency BUG"), tty_flip_buffer_push() always schedules a work item to push data to the line discipline and there's no need to keep any low_latency hacks around. Link: https://lore.kernel.org/linux-serial/cover.1376923198.git.viresh.kumar@linaro.org/ Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20210421095509.3024-8-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-22serial: apbuart: drop low-latency workaroundJohan Hovold1-2/+0
Commit 78d34d75c84d ("tty: serial: apbuart: drop uart_port->lock before calling tty_flip_buffer_push()") claimed to address a locking issue but only provided a dubious lockdep splat from an unrelated driver, which in the end turned out to be due a broken local change carried by the author. Unfortunately these patches were merged before the issue had been analysed properly so the commit messages makes no sense whatsoever. The real issue was first seen on RT which at the time effectively always set the low_latency flag for all serial drivers by patching tty_flip_buffer_push(). This in turn revealed that many drivers did not handle the infamous low_latency behaviour which meant that data was pushed immediately to the line discipline instead of being deferred to a work queue. Since commit a9c3f68f3cd8 ("tty: Fix low_latency BUG"), tty_flip_buffer_push() always schedules a work item to push data to the line discipline and there's no need to keep any low_latency hacks around. Link: https://lore.kernel.org/linux-serial/cover.1376923198.git.viresh.kumar@linaro.org/ Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20210421095509.3024-7-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-22serial: amba-pl011: drop low-latency workaroundJohan Hovold1-2/+0
Commit ead76f329f77 ("ARM: 6763/1: pl011: add optional RX DMA to PL011 v2") added RX DMA support and also reproduced the workaround for the infamous low_latency behaviour of tty_flip_buffer_push() by dropping and reacquiring the port lock during receive processing. Since commit a9c3f68f3cd8 ("tty: Fix low_latency BUG"), tty_flip_buffer_push() always schedules a work item to push data to the line discipline and there's no need to keep any low_latency hacks around. Note that the port lock is also dropped in the PIO path (see pl011_rx_chars), but it is not clear whether this is still needed by the DMA code added by the aforementioned commit. Cc: Linus Walleij <linus.walleij@linaro.org> Cc: Russell King <linux@armlinux.org.uk> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20210421095509.3024-6-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-22serial: amba-pl010: drop low-latency workaroundJohan Hovold1-2/+0
Commit 2389b272168c ("[ARM] 4417/1: Serial: Fix AMBA drivers locking") worked around the infamous low_latency behaviour of tty_flip_buffer_push() by simply dropping and reacquiring the port lock in the interrupt handler. Since commit a9c3f68f3cd8 ("tty: Fix low_latency BUG"), tty_flip_buffer_push() always schedules a work item to push data to the line discipline and there's no need to keep any low_latency hacks around. Cc: Russell King <linux@armlinux.org.uk> Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20210421095509.3024-5-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-22serial: altera_uart: drop low-latency workaroundJohan Hovold1-2/+0
Commit dd085ed8ef6c ("tty: serial: altera: drop uart_port->lock before calling tty_flip_buffer_push()") claimed to address a locking issue but only provided a dubious lockdep splat from an unrelated driver, which in the end turned out to be due a broken local change carried by the author. Unfortunately these patches were merged before the issue had been analysed properly so the commit messages makes no sense whatsoever. The real issue was first seen on RT which at the time effectively always set the low_latency flag for all serial drivers by patching tty_flip_buffer_push(). This in turn revealed that many drivers did not handle the infamous low_latency behaviour which meant that data was pushed immediately to the line discipline instead of being deferred to a work queue. Since commit a9c3f68f3cd8 ("tty: Fix low_latency BUG"), tty_flip_buffer_push() always schedules a work item to push data to the line discipline and there's no need to keep any low_latency hacks around. Link: https://lore.kernel.org/linux-serial/cover.1376923198.git.viresh.kumar@linaro.org/ Cc: Tobias Klauser <tklauser@distanz.ch> Acked-by: Tobias Klauser <tklauser@distanz.ch> Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20210421095509.3024-4-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-22serial: altera_jtaguart: drop low-latency workaroundJohan Hovold1-2/+0
Commit 53dd0ba7a6f4 ("tty: serial: altera_jtag: drop uart_port->lock before calling tty_flip_buffer_push()") claimed to address a locking issue but only provided a dubious lockdep splat from an unrelated driver, which in the end turned out to be due a broken local change carried by the author. Unfortunately these patches were merged before the issue had been analysed properly so the commit messages makes no sense whatsoever. The real issue was first seen on RT which at the time effectively always set the low_latency flag for all serial drivers by patching tty_flip_buffer_push(). This in turn revealed that many drivers did not handle the infamous low_latency behaviour which meant that data was pushed immediately to the line discipline instead of being deferred to a work queue. Since commit a9c3f68f3cd8 ("tty: Fix low_latency BUG"), tty_flip_buffer_push() always schedules a work item to push data to the line discipline and there's no need to keep any low_latency hacks around. Link: https://lore.kernel.org/linux-serial/cover.1376923198.git.viresh.kumar@linaro.org/ Cc: Tobias Klauser <tklauser@distanz.ch> Acked-by: Tobias Klauser <tklauser@distanz.ch> Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20210421095509.3024-3-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-22serial: omap: fix rs485 half-duplex filteringDario Binacchi1-15/+24
Data received during half-duplex transmission must be filtered. If the target device responds quickly, emptying the FIFO at the end of the transmission can erase not only the echo characters but also part of the response message. By keeping the receive interrupt enabled even during transmission, it allows you to filter each echo character and only in a number equal to those transmitted. The issue was generated by a target device that started responding 240us later having received a request in communication at 115200bps. Sometimes, some messages received by the target were missing some of the first bytes. Fixes: 3a13884abea0 ("tty/serial: omap: empty the RX FIFO at the end of half-duplex TX") Signed-off-by: Dario Binacchi <dariobin@libero.it> Link: https://lore.kernel.org/r/20210418094705.27014-1-dariobin@libero.it Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-22serial: omap: don't disable rs485 if rts gpio is missingDario Binacchi1-8/+4
There are rs485 transceivers (e.g. MAX13487E/MAX13488E) which automatically disable or enable the driver and receiver to keep the bus in the correct state. In these cases we don't need a GPIO for flow control. Fixes: 4a0ac0f55b18 ("OMAP: add RS485 support") Signed-off-by: Dario Binacchi <dariobin@libero.it> Link: https://lore.kernel.org/r/20210415210945.25863-1-dariobin@libero.it Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-22serial: stm32: defer sysrq processingJohan Hovold1-10/+6
Use the uart_unlock_and_check_sysrq() helper to defer sysrq processing until receive processing is done and the port lock has been released. This allows cleaning up the console_write() implementation by not having to work around the recursive sysrq case (by dropping locking completely) and also makes the console code work with PREEMPT_RT by no longer relying on local_irq_save(). Reviewed-by: Valentin Caron<valentin.caron@foss.st.com> Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20210416140557.25177-4-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-22serial: stm32: fix threaded interrupt handlingJohan Hovold1-10/+12
When DMA is enabled the receive handler runs in a threaded handler, but the primary handler up until very recently neither disabled interrupts in the device or used IRQF_ONESHOT. This would lead to a deadlock if an interrupt comes in while the threaded receive handler is running under the port lock. Commit ad7676812437 ("serial: stm32: fix a deadlock condition with wakeup event") claimed to fix an unrelated deadlock, but unfortunately also disabled interrupts in the threaded handler. While this prevents the deadlock mentioned in the previous paragraph it also defeats the purpose of using a threaded handler in the first place. Fix this by making the interrupt one-shot and not disabling interrupts in the threaded handler. Note that (receive) DMA must not be used for a console port as the threaded handler could be interrupted while holding the port lock, something which could lead to a deadlock in case an interrupt handler ends up calling printk. Fixes: ad7676812437 ("serial: stm32: fix a deadlock condition with wakeup event") Fixes: 3489187204eb ("serial: stm32: adding dma support") Cc: stable@vger.kernel.org # 4.9 Cc: Alexandre TORGUE <alexandre.torgue@st.com> Cc: Gerald Baeza <gerald.baeza@st.com> Reviewed-by: Valentin Caron<valentin.caron@foss.st.com> Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20210416140557.25177-3-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-22serial: do not restore interrupt state in sysrq helperJohan Hovold5-17/+17
The uart_unlock_and_check_sysrq() helper can be used to defer processing of sysrq until the interrupt handler has released the port lock and is about to return. Since commit 81e2073c175b ("genirq: Disable interrupts for force threaded handlers") interrupt handlers that are not explicitly requested as threaded are always called with interrupts disabled and there is no need to save the interrupt state when taking the port lock. Instead of adding another sysrq helper for when the interrupt state has not needlessly been saved, drop the state parameter from uart_unlock_and_check_sysrq() and update its callers to no longer explicitly disable interrupts in their interrupt handlers. Cc: Joel Stanley <joel@jms.id.au> Cc: Andrew Jeffery <andrew@aj.id.au> Cc: Andy Gross <agross@kernel.org> Cc: Bjorn Andersson <bjorn.andersson@linaro.org> Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20210416140557.25177-2-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-15serial: sh-sci: remove obsolete latency workaroundUlrich Hecht1-12/+1
Since the transition to hrtimers there is no more need to set a minimum RX timeout to work around latency issues. Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Signed-off-by: Ulrich Hecht <uli+renesas@fpond.eu> Link: https://lore.kernel.org/r/20210415093547.21639-1-uli+renesas@fpond.eu Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-15serial: 8250_aspeed_vuart: add aspeed, lpc-io-reg and aspeed, lpc-interrupts ↵Zev Weiss1-2/+49
DT properties These allow describing all the Aspeed VUART attributes currently available via sysfs. aspeed,lpc-interrupts provides a replacement for the deprecated aspeed,sirq-polarity-sense property. Reviewed-by: Andrew Jeffery <andrew@aj.id.au> Signed-off-by: Zev Weiss <zev@bewilderbeest.net> Link: https://lore.kernel.org/r/20210412034712.16778-4-zev@bewilderbeest.net Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-15serial: 8250_aspeed_vuart: refactor sirq and lpc address setting codeZev Weiss1-16/+35
This splits dedicated aspeed_vuart_set_{sirq,lpc_address}() functions out of the sysfs store functions in preparation for adding DT properties that will be poking the same registers. While we're at it, these functions now provide some basic bounds-checking on their arguments. Reviewed-by: Andrew Jeffery <andrew@aj.id.au> Signed-off-by: Zev Weiss <zev@bewilderbeest.net> Link: https://lore.kernel.org/r/20210412034712.16778-3-zev@bewilderbeest.net Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-12Merge branch 'opp/linux-next' of ↵Rafael J. Wysocki1-15/+8
git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm Pull OPP (Operating Performance Points) framework updates for v5.13 from Viresh Kumar: "This adds devm variants for OPP APIs and updates few of the users as well (Yangtao Li and Dmitry Osipenko)." * 'opp/linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm: memory: samsung: exynos5422-dmc: Convert to use resource-managed OPP API drm/panfrost: Convert to use resource-managed OPP API drm/lima: Convert to use resource-managed OPP API mmc: sdhci-msm: Convert to use resource-managed OPP API spi: spi-qcom-qspi: Convert to use resource-managed OPP API spi: spi-geni-qcom: Convert to use resource-managed OPP API serial: qcom_geni_serial: Convert to use resource-managed OPP API opp: Change return type of devm_pm_opp_attach_genpd() opp: Change return type of devm_pm_opp_register_set_opp_helper() opp: Add devres wrapper for dev_pm_opp_of_add_table opp: Add devres wrapper for dev_pm_opp_set_supported_hw opp: Add devres wrapper for dev_pm_opp_set_regulators opp: Add devres wrapper for dev_pm_opp_set_clkname
2021-04-10serial: Add missing MODULE_DEVICE_TABLEBixuan Cui1-0/+1
This patch adds missing MODULE_DEVICE_TABLE definition which generates correct modalias for automatic loading of this driver when it is built as an external module. Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Bixuan Cui <cuibixuan@huawei.com> Link: https://lore.kernel.org/r/20210410035048.11466-1-cuibixuan@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-10serial: core: return early on unsupported ioctlsJohan Hovold1-3/+3
Drivers can return -ENOIOCTLCMD when an ioctl is not recognised to tell the upper layers to continue looking for a handler. This is not the case for the RS485 and ISO7816 ioctls whose handlers should return -ENOTTY directly in case a serial driver does not implement the corresponding methods. Fixes: a5f276f10ff7 ("serial_core: Handle TIOC[GS]RS485 ioctls.") Fixes: ad8c0eaa0a41 ("tty/serial_core: add ISO7816 infrastructure") Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20210407095208.31838-9-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-10serial: core: drop redundant TIOCGSERIAL memsetJohan Hovold1-2/+0
Since commit 5099d234a52a ("serial_core: switch to ->[sg]et_serial()") the serial structure passed to uart_get_info() has already have been cleared by the tty layer so drop the redundant memset. Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20210407095208.31838-8-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-06tty: serial: ucc_uart: replace qe_io{read,write}* wrappers by generic ↵Christophe Leroy1-62/+62
io{read,write}* Commit 6ac9b61786cc ("soc: fsl: qe: introduce qe_io{read,write}* wrappers") added specific I/O accessors for qe because at that time ioread/iowrite functions were sub-optimal on powerpc/32 compared to the architecture specific in_/out_ IO accessors. But as ioread/iowrite accessors are now equivalent since commit 894fa235eb4c ("powerpc: inline iomap accessors"), use them in order to allow removal of the qe specific ones. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Li Yang <leoyang.li@nxp.com>
2021-04-05sc16is7xx: Defer probe if device read failsAnnaliese McDermond1-1/+1
A test was added to the probe function to ensure the device was actually connected and working before successfully completing a probe. If the device was actually there, but the I2C bus was not ready yet for whatever reason, the probe fails permanently. Change the probe so that we defer the probe on a regmap read failure so that we try the probe again when the dependent drivers are potentially loaded. This should not affect the case where the device truly isn't present because the probe will never successfully complete. Fixes: 2aa916e67db3 ("sc16is7xx: Read the LSR register for basic device presence check") Cc: stable@vger.kernel.org Signed-off-by: Annaliese McDermond <nh6z@nh6z.net> Link: https://lore.kernel.org/r/010101787f9c3fd8-c1815c00-2d6b-4c85-a96a-a13e68597fda-000000@us-west-2.amazonses.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-05tty/serial: Add rx-tx-swap OF option to stm32-usartMartin Devera2-1/+14
STM32 F7/H7 usarts supports RX & TX pin swapping. Add option to turn it on. Tested on STM32MP157. Acked-by: Fabrice Gasnier <fabrice.gasnier@foss.st.com> Signed-off-by: Martin Devera <devik@eaxlabs.cz> Link: https://lore.kernel.org/r/20210328154306.22674-2-devik@eaxlabs.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-05Merge 5.12-rc6 into tty-nextGreg Kroah-Hartman3-10/+0
We need the serial/tty fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-03Merge tag 'tty-5.12-rc6' of ↵Linus Torvalds1-7/+0
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty Pull serial driver fix from Greg KH: "Here is a single serial driver fix for 5.12-rc6. Is is a revert of a change that showed up in 5.9 that has been reported to cause problems. It has been in linux-next for a while with no reported issues" * tag 'tty-5.12-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: soc: qcom-geni-se: Cleanup the code to remove proxy votes
2021-04-02serial: 8250: Make symbol 'brcmuart_debugfs_root' staticZucheng Zheng1-1/+1
symbol 'brcmuart_debugfs_root' is not used outside of 8250_bcm7271.c, so this commit marks it static. Signed-off-by: Zucheng Zheng <zhengzucheng@huawei.com> Link: https://lore.kernel.org/r/20210401074919.56573-1-zhengzucheng@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-02serial: 8250_bcm7271: Fix return value check in brcmuart_probe()Wei Yongjun1-2/+2
In case of error, the function devm_ioremap() returns NULL pointer not ERR_PTR(). The IS_ERR() test in the return value check should be replaced with NULL test. Fixes: 41a469482de2 ("serial: 8250: Add new 8250-core based Broadcom STB driver") Reported-by: Hulk Robot <hulkci@huawei.com> Reviewed-by: Al Cooper <alcooperx@gmail.com> Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com> Link: https://lore.kernel.org/r/20210329140659.1832950-1-weiyongjun1@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-28serial: 8250_of: Add nuvoton,wpcm450-uartJonathan Neuschäfer1-0/+1
Add a compatible string for the UART inside the Nuvoton WPCM450 SoC. It works the same as the UART in NPCM750. Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> Link: https://lore.kernel.org/r/20210320181610.680870-10-j.neuschaefer@gmx.net Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-26serial: 8250: Add new 8250-core based Broadcom STB driverAl Cooper3-0/+1213
Add a UART driver for the new Broadcom 8250 based STB UART. The new UART is backward compatible with the standard 8250, but has some additional features. The new features include a high accuracy baud rate clock system and DMA support. The driver will use the new optional BAUD MUX clock to select the best one of the four master clocks (81MHz, 108MHz, 64MHz and 48MHz) to feed the baud rate selection logic for any requested baud rate. This allows for more accurate BAUD rates when high speed baud rates are selected. The driver will use the new UART DMA hardware if the UART DMA registers are specified in Device Tree "reg" property. The driver also sets the UPSTAT_AUTOCTS flag when hardware flow control is enabled. This flag is needed for UARTs that don't assert a CTS changed interrupt when CTS changes and AFE (Hardware Flow Control) is enabled. The driver also contains a workaround for a bug in the Synopsis 8250 core. The problem is that at high baud rates, the RX partial FIFO timeout interrupt can occur but there is no RX data (DR not set in the LSR register). In this case the driver will not read the Receive Buffer Register, which clears the interrupt, and the system will get continuous UART interrupts until the next RX character arrives. The fix originally suggested by Synopsis was to read the Receive Buffer Register and discard the character when the DR bit in the LSR was not set, to clear the interrupt. The problem was that occasionally a character would arrive just after the DR bit check and a valid character would be discarded. The fix that was added will clear receive interrupts to stop the interrupt, deassert RTS to insure that no new data can arrive, wait for 1.5 character times for the sender to react to RTS and then check for data and either do a dummy read or a valid read. Debugfs error counters were also added and were used to help create test software that would cause the error condition. The counters can be found at: /sys/kernel/debug/bcm7271-uart/<device-name>/stats This also includes a few fixes for build warnings reported by the kernel test robot. Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Al Cooper <alcooperx@gmail.com> Link: https://lore.kernel.org/r/20210325185256.16156-3-alcooperx@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-26soc: qcom-geni-se: Cleanup the code to remove proxy votesRoja Rani Yarubandi1-7/+0
This reverts commit 048eb908a1f2 ("soc: qcom-geni-se: Add interconnect support to fix earlycon crash") ICC core and platforms drivers supports sync_state feature, which ensures that the default ICC BW votes from the bootloader is not removed until all it's consumers are probes. The proxy votes were needed in case other QUP child drivers I2C, SPI probes before UART, they can turn off the QUP-CORE clock which is shared resources for all QUP driver, this causes unclocked access to HW from earlycon. Given above support from ICC there is no longer need to maintain proxy votes on QUP-CORE ICC node from QUP wrapper driver for early console usecase, the default votes won't be removed until real console is probed. Cc: stable@vger.kernel.org Fixes: 266cd33b5913 ("interconnect: qcom: Ensure that the floor bandwidth value is enforced") Fixes: 7d3b0b0d8184 ("interconnect: qcom: Use icc_sync_state") Signed-off-by: Roja Rani Yarubandi <rojay@codeaurora.org> Signed-off-by: Akash Asthana <akashast@codeaurora.org> Reviewed-by: Matthias Kaehlcke <mka@chromium.org> Link: https://lore.kernel.org/r/20210324101836.25272-2-rojay@codeaurora.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-23serial: imx: drop workaround for forced irq threadingJohan Hovold1-8/+2
Force-threaded interrupt handlers used to run with interrupts enabled, something which could lead to deadlocks in case a threaded handler shared a lock with code running in hard interrupt context (e.g. timer callbacks) and did not explicitly disable interrupts. This was specifically the case for serial drivers that take the port lock in their console write path as printk can be called from hard interrupt context also with forced threading ("threadirqs"). Since commit 81e2073c175b ("genirq: Disable interrupts for force threaded handlers") interrupt handlers always run with interrupts disabled on non-RT so that drivers no longer need to do handle this. Drop the now obsolete workaround added by commit 33f16855dcb9 ("tty: serial: imx: fix potential deadlock"). Cc: Sam Nobs <samuel.nobs@taitradio.com> Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20210322111036.31966-1-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-23serial: pch_uart: fix build error with !CONFIG_DEBUG_FSWei Yongjun1-3/+0
Fix the build error with CONFIG_DEBUG_FS is not set: drivers/tty/serial/pch_uart.c: In function 'pch_uart_init_port': drivers/tty/serial/pch_uart.c:1815:9: error: 'port_regs_ops' undeclared (first use in this function) 1815 | &port_regs_ops); | ^~~~~~~~~~~~~ This commit get rid of the CONFIG_PM_SLEEP ifdefery to fix the build error. Fixes: 1f8a51ee3242 ("tty: serial: pch_uart.c: remove debugfs dentry pointer") Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com> Link: https://lore.kernel.org/r/20210322122601.2980258-1-weiyongjun1@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-23serial: stm32: update wakeup IRQ managementAlexandre Torgue2-22/+12
The wakeup specific IRQ management is no more needed to wake up the stm32 plaform. A relationship has been established between the EXTI and the EVENT IRQ, just need to declare the EXTI interrupt instead of the UART event IRQ. Signed-off-by: Alexandre Torgue <alexandre.torgue@foss.st.com> Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com> Link: https://lore.kernel.org/r/20210319184253.5841-5-erwan.leray@foss.st.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-23serial: stm32: clean wakeup handling in serial_suspendErwan Le Ray1-2/+0
Remove useless call to stm32_usart_serial_en_wakeup() routine in suspend callback. When called with "false" argument, this routine is clearing UESM and WUFIE bits if usart is not wakeup source. Those bits are already cleared in set_termios(), and then in serial_resume() callback when usart is wakeup source. Signed-off-by: Alexandre Torgue <alexandre.torgue@foss.st.com> Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com> Link: https://lore.kernel.org/r/20210319184253.5841-3-erwan.leray@foss.st.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-23serial: stm32: rework wakeup managementErwan Le Ray1-3/+3
Rework wakeup management by activating uart as wakeup source when usart device OR its tty virtual device parent is wakeup source. This patch aim to avoid potential misalignment between serial and tty wakeup flags. Signed-off-by: Patrice Chotard <patrice.chotard@foss.st.com> Signed-off-by: Alexandre Torgue <alexandre.torgue@foss.st.com> Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com> Link: https://lore.kernel.org/r/20210319184253.5841-2-erwan.leray@foss.st.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-23drivers: tty: serial: sh-sci: fix spelling typo of 'wheter'Wang Qing1-1/+1
wheter -> whether Signed-off-by: Wang Qing <wangqing@vivo.com> Link: https://lore.kernel.org/r/1615345622-2015-1-git-send-email-wangqing@vivo.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-23tty: max310x: fix flexible_array.cocci warningskernel test robot1-1/+1
Zero-length and one-element arrays are deprecated, see Documentation/process/deprecated.rst Flexible-array members should be used instead. Generated by: scripts/coccinelle/misc/flexible_array.cocci Fixes: 10d8b34a42171 ("serial: max310x: Driver rework") CC: Denis Efremov <efremov@linux.com> Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: kernel test robot <lkp@intel.com> Signed-off-by: Julia Lawall <julia.lawall@inria.fr> Link: https://lore.kernel.org/r/alpine.DEB.2.22.394.2103091516020.2892@hadrien Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-23tty: serial: 8250: delete redundant printing of return valueWang Qing1-4/+1
platform_get_irq() has already checked and printed the return value, the printing here is nothing special, it is not necessary at all. Signed-off-by: Wang Qing <wangqing@vivo.com> Link: https://lore.kernel.org/r/1615621707-2330-1-git-send-email-wangqing@vivo.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-23tty: serial: samsung_tty: remove spinlock flags in interrupt handlersKrzysztof Kozlowski1-9/+6
Since interrupt handler is called with disabled local interrupts, there is no need to use the spinlock primitives disabling interrupts as well. Suggested-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Johan Hovold <johan@kernel.org> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com> Link: https://lore.kernel.org/r/20210315181212.113217-1-krzysztof.kozlowski@canonical.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-17module: remove never implemented MODULE_SUPPORTED_DEVICELeon Romanovsky2-3/+0
MODULE_SUPPORTED_DEVICE was added in pre-git era and never was implemented. We can safely remove it, because the kernel has grown to have many more reliable mechanisms to determine if device is supported or not. Signed-off-by: Leon Romanovsky <leonro@nvidia.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-16serial: qcom_geni_serial: Convert to use resource-managed OPP APIYangtao Li1-15/+8
Use resource-managed OPP API to simplify code. Signed-off-by: Yangtao Li <tiny.windzz@gmail.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2021-03-15Merge 5.12-rc3 into tty-nextGreg Kroah-Hartman1-24/+5
Resolves a merge issue with: drivers/tty/hvc/hvcs.c and we want the tty/serial fixes from 5.12-rc3 in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-10serial: stm32: add support for "flush_buffer" opsErwan Le Ray1-0/+14
Add the support for "flush_buffer" ops in order to flush any write buffers, reset any DMA state and stop any ongoing DMA transfers when the port->state->xmit circular buffer is cleared. Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com> Link: https://lore.kernel.org/r/20210304162308.8984-14-erwan.leray@foss.st.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-10serial: stm32: fix tx_empty conditionErwan Le Ray2-4/+4
In "tx_empty", we should poll TC bit in both DMA and PIO modes (instead of TXE) to check transmission data register has been transmitted independently of the FIFO mode. TC indicates that both transmit register and shift register are empty. When shift register is empty, tx_empty should return TIOCSER_TEMT instead of TC value. Cleans the USART_CR_TC TCCF register define (transmission complete clear flag) as it is duplicate of USART_ICR_TCCF. Fixes: 48a6092fb41f ("serial: stm32-usart: Add STM32 USART Driver") Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com> Link: https://lore.kernel.org/r/20210304162308.8984-13-erwan.leray@foss.st.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-10serial: stm32: add FIFO flush when port is closedErwan Le Ray1-0/+5
Transmission complete error is sent when ISR_TC is not set. If port closure is requested despite data in TDR / TX FIFO has not been sent (because of flow control), ISR_TC is not set and error message is sent on port closure but also when a new port is opened. Flush the data when port is closed, so the error isn't printed twice upon next port opening. Fixes: 64c32eab6603 ("serial: stm32: Add support of TC bit status check") Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com> Link: https://lore.kernel.org/r/20210304162308.8984-12-erwan.leray@foss.st.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-10serial: stm32: fix FIFO flush in startup and set_termiosErwan Le Ray1-3/+3
Fifo flush set USART_RQR register by calling stm32_usart_set_bits routine (Read/Modify/Write). USART_RQR register is a write only register. So, read before write isn't correct / relevant to flush the FIFOs. Replace stm32_usart_set_bits call by writel_relaxed. Fixes: 84872dc448fe ("serial: stm32: add RX and TX FIFO flush") Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com> Link: https://lore.kernel.org/r/20210304162308.8984-11-erwan.leray@foss.st.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-10serial: stm32: call stm32_transmit_chars lockedErwan Le Ray1-0/+3
stm32_transmit_chars should be called under lock also in tx DMA callback. Fixes: 3489187204eb ("serial: stm32: adding dma support") Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com> Signed-off-by: Fabrice Gasnier <fabrice.gasnier@foss.st.com> Link: https://lore.kernel.org/r/20210304162308.8984-10-erwan.leray@foss.st.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-10serial: stm32: fix tx dma completion, release channelErwan Le Ray1-0/+1
This patch add a proper release of dma channels when completing dma tx. Fixes: 3489187204eb ("serial: stm32: adding dma support") Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com> Link: https://lore.kernel.org/r/20210304162308.8984-9-erwan.leray@foss.st.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-10serial: stm32: fix a deadlock in set_termiosErwan Le Ray1-6/+6
CTS/RTS GPIOs support that has been added recently to STM32 UART driver has introduced scheduled code in a set_termios part protected by a spin lock. This generates a potential deadlock scenario: Chain exists of: &irq_desc_lock_class --> console_owner --> &port_lock_key Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&port_lock_key); lock(console_owner); lock(&port_lock_key); lock(&irq_desc_lock_class); *** DEADLOCK *** 4 locks held by stty/766: Move the scheduled code after the spinlock. Fixes: 6cf61b9bd7cc ("tty: serial: Add modem control gpio support for STM32 UART") Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com> Link: https://lore.kernel.org/r/20210304162308.8984-8-erwan.leray@foss.st.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-10serial: stm32: fix wake-up flag handlingErwan Le Ray1-13/+19
This patch fixes several issue with wake-up handling: - the WUF irq is handled several times at wake-up - the USART is disabled / enabled at suspend to set wake-up flag. It can cause glitches during RX. This patch fix those issues: - clear wake-up flag and disable wake-up irq in WUF irq handling - enable wake-up from low power on start bit detection at port configuration - Unmask the wake-up flag irq at suspend and mask it at resume In addition, pm_wakeup_event handling is moved from receice_chars to WUF irq handling. Fixes: 270e5a74fe4c ("serial: stm32: add wakeup mechanism") Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com> Link: https://lore.kernel.org/r/20210304162308.8984-7-erwan.leray@foss.st.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-10serial: stm32: fix a deadlock condition with wakeup eventErwan Le Ray1-12/+15
Deadlock issue is seen when enabling CONFIG_PROVE_LOCKING=Y, and uart console as wakeup source. Deadlock occurs when resuming from low power mode if system is waked up via usart console. The deadlock is triggered 100% when also disabling console suspend prior to go to suspend. Simplified call stack, deadlock condition: - stm32_console_write <-- spin_lock already held - print_circular_bug - pm_wakeup_dev_event <-- triggers lockdep as seen above - stm32_receive_chars - stm32_interrupt <-- wakeup via uart console, takes the lock So, revisit spin_lock in stm32-usart driver: - there is no need to hold the lock to access ICR (atomic clear of status flags) - only hold the lock inside stm32_receive_chars() routine (no need to call pm_wakeup_dev_event with lock held) - keep stm32_transmit_chars() routine called with lock held Fixes: 48a6092fb41f ("serial: stm32-usart: Add STM32 USART Driver") Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com> Signed-off-by: Fabrice Gasnier <fabrice.gasnier@foss.st.com> Link: https://lore.kernel.org/r/20210304162308.8984-6-erwan.leray@foss.st.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-10serial: stm32: fix TX and RX FIFO thresholdsErwan Le Ray1-14/+9
TX and RX FIFO thresholds may be cleared after suspend/resume, depending on the low power mode. Those configurations (done in startup) are not effective for UART console, as: - the reference manual indicates that FIFOEN bit can only be written when the USART is disabled (UE=0) - a set_termios (where UE is set) is requested firstly for console enabling, before the startup. Fixes: 84872dc448fe ("serial: stm32: add RX and TX FIFO flush") Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com> Link: https://lore.kernel.org/r/20210304162308.8984-5-erwan.leray@foss.st.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>