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path: root/drivers/tty/serial/8250
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2025-06-08treewide, timers: Rename from_timer() to timer_container_of()Ingo Molnar
Move this API to the canonical timer_*() namespace. [ tglx: Redone against pre rc1 ] Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/aB2X0jCKQO56WdMt@gmail.com
2025-05-22tty: serial: 8250_omap: fix TX with DMA for am33xxJiri Slaby (SUSE)
Commit 1788cf6a91d9 ("tty: serial: switch from circ_buf to kfifo") introduced an error in the TX DMA handling for 8250_omap. When the OMAP_DMA_TX_KICK flag is set, the "skip_byte" is pulled from the kfifo and emitted directly in order to start the DMA. While the kfifo is updated, dma->tx_size is not decreased. This leads to uart_xmit_advance() called in omap_8250_dma_tx_complete() advancing the kfifo by one too much. In practice, transmitting N bytes has been seen to result in the last N-1 bytes being sent repeatedly. This change fixes the problem by moving all of the dma setup after the OMAP_DMA_TX_KICK handling and using kfifo_len() instead of the DMA size for the 4-byte cutoff check. This slightly changes the behaviour at buffer wraparound, but it still transmits the correct bytes somehow. Now, the "skip_byte" would no longer be accounted to the stats. As previously, dma->tx_size included also this skip byte, up->icount.tx was updated by aforementioned uart_xmit_advance() in omap_8250_dma_tx_complete(). Fix this by using the uart_fifo_out() helper instead of bare kfifo_get(). Based on patch by Mans Rullgard <mans@mansr.com> Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org> Fixes: 1788cf6a91d9 ("tty: serial: switch from circ_buf to kfifo") Link: https://lore.kernel.org/all/20250506150748.3162-1-mans@mansr.com/ Reported-by: Mans Rullgard <mans@mansr.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20250522053835.3495975-1-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-05-018250: microchip: pci1xxxx: Add PCIe Hot reset disable support for Rev C0 and ↵Rengarajan S
later devices Systems that issue PCIe hot reset requests during a suspend/resume cycle cause PCI1XXXX device revisions prior to C0 to get its UART configuration registers reset to hardware default values. This results in device inaccessibility and data transfer failures. Starting with Revision C0, support was added in the device hardware (via the Hot Reset Disable Bit) to allow resetting only the PCIe interface and its associated logic, but preserving the UART configuration during a hot reset. This patch enables the hot reset disable feature during suspend/ resume for C0 and later revisions of the device. Signed-off-by: Rengarajan S <rengarajan.s@microchip.com> Reviewed-by: Jiri Slaby <jirislaby@kernel.org> Link: https://lore.kernel.org/r/20250425145500.29036-1-rengarajan.s@microchip.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-04-25serial: 8250: unexport serial8250_rpm_*() functionsJiri Slaby (SUSE)
Since commit 8700a7ea5519 (serial: 8250_omap: Drop pm_runtime_irq_safe()), all the serial8250_rpm_*() functions are used solely in 8250_port. Unexport them. Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org> Link: https://lore.kernel.org/r/20250425111315.1036184-7-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-04-25serial: switch uart_port::iotype to enum uart_iotypeJiri Slaby (SUSE)
The inline-defined constants look weird. Instead, define a proper enum for them and type uart_port::iotype as that enum. This allows for proper checking in switch-case labels (somewhere, a default or UPIO_UNKNOWN label needs to be added/handled). Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org> Link: https://lore.kernel.org/r/20250425111315.1036184-4-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-04-15serial: 8250_of: manage bus clock in suspend/resumeAlex Elder
Save the bus clock pointer in the of_serial_info structure, and use that to disable the bus clock on suspend and re-enable it on resume. Signed-off-by: Alex Elder <elder@riscstar.com> Reviewed-by: Andy Shevchenko <andy@kernel.org> Reviewed-by: Yixun Lan <dlan@gentoo.org> Link: https://lore.kernel.org/r/20250411203828.1491595-4-elder@riscstar.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-04-11serial: 8250_of: add support for an optional bus clockAlex Elder
The SpacemiT UART requires a bus clock to be enabled, in addition to it's "normal" core clock. Look up the optional bus clock by name, and if that's found, look up the core clock using the name "core". Supplying a bus clock is optional. If no bus clock is needed, the the first/only clock is used for the core clock. Signed-off-by: Alex Elder <elder@riscstar.com> Link: https://lore.kernel.org/r/20250409192213.1130181-3-elder@riscstar.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-04-11serial: 8250_ni: Tidy up ACPI ID tableAndy Shevchenko
Tidy up ACPI ID table: - drop ACPI_PTR() and hence replace acpi.h with mod_devicetable.h et al. - drop comma in the terminator entry With that done, extend compile test coverage. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Tested-by: Chaitanya Vadrevu <chaitanya.vadrevu@emerson.com> Reviewed-by: Chaitanya Vadrevu <chaitanya.vadrevu@emerson.com> Link: https://lore.kernel.org/r/20250321182119.454507-8-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-04-11serial: 8250_ni: Switch to use dev_err_probe()Andy Shevchenko
Switch to use dev_err_probe() to simplify the error path and unify a message template. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Tested-by: Chaitanya Vadrevu <chaitanya.vadrevu@emerson.com> Reviewed-by: Chaitanya Vadrevu <chaitanya.vadrevu@emerson.com> Link: https://lore.kernel.org/r/20250321182119.454507-7-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-04-11serial: 8250_ni: use serial_port_in()/serial_port_out() helpersAndy Shevchenko
There are serial_port_in()/serial_port_out() helpers to be used instead of direct p->serial_in()/p->serial_out(). Use them in various 8250 drivers. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Tested-by: Chaitanya Vadrevu <chaitanya.vadrevu@emerson.com> Reviewed-by: Chaitanya Vadrevu <chaitanya.vadrevu@emerson.com> Link: https://lore.kernel.org/r/20250321182119.454507-6-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-04-11serial: 8250_ni: Remove unneeded conditionalsAndy Shevchenko
It doesn't matter if the properties are supplied or not in the struct ni16550_device_info as default in any case is 0. Hence there is no need to check for them being set. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Tested-by: Chaitanya Vadrevu <chaitanya.vadrevu@emerson.com> Reviewed-by: Chaitanya Vadrevu <chaitanya.vadrevu@emerson.com> Link: https://lore.kernel.org/r/20250321182119.454507-5-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-04-11serial: 8250_ni: Switch to use platform_get_mem_or_io()Andy Shevchenko
Switch to use new platform_get_mem_or_io() instead of home grown analogue. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Tested-by: Chaitanya Vadrevu <chaitanya.vadrevu@emerson.com> Reviewed-by: Chaitanya Vadrevu <chaitanya.vadrevu@emerson.com> Link: https://lore.kernel.org/r/20250321182119.454507-4-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-04-11serial: 8250_ni: Remove duplicate mappingAndy Shevchenko
UPF_IOREMAP is for serial core to map the resource on behalf of the driver. No need to perform this explicitly in the driver. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Tested-by: Chaitanya Vadrevu <chaitanya.vadrevu@emerson.com> Reviewed-by: Chaitanya Vadrevu <chaitanya.vadrevu@emerson.com> Link: https://lore.kernel.org/r/20250321182119.454507-3-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-04-11serial: 8250_ni: Switch to use uart_read_port_properties()Andy Shevchenko
Since we have now a common helper to read port properties use it instead of sparse home grown solution. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Tested-by: Chaitanya Vadrevu <chaitanya.vadrevu@emerson.com> Reviewed-by: Chaitanya Vadrevu <chaitanya.vadrevu@emerson.com> Link: https://lore.kernel.org/r/20250321182119.454507-2-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-04-05treewide: Switch/rename to timer_delete[_sync]()Thomas Gleixner
timer_delete[_sync]() replaces del_timer[_sync](). Convert the whole tree over and remove the historical wrapper inlines. Conversion was done with coccinelle plus manual fixups where necessary. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2025-03-20serial: 8250: add driver for NI UARTsChaitanya Vadrevu
The National Instruments (NI) 16550 is a 16550-like UART with larger FIFOs and embedded RS-232/RS-485 transceiver control circuitry. This patch adds a driver that can operate this UART, which is used for onboard serial ports in several NI embedded controller designs. Portions of this driver were originally written by Jaeden Amero and Karthik Manamcheri, with extensive cleanups and refactors since by Brenda Streiff. Cc: Gratian Crisan <gratian.crisan@emerson.com> Co-developed-by: Jason Smith <jason.smith@emerson.com> Signed-off-by: Jason Smith <jason.smith@emerson.com> Signed-off-by: Chaitanya Vadrevu <chaitanya.vadrevu@emerson.com> Link: https://lore.kernel.org/r/a3b0df6d-1dd5-4cc4-a7e1-4ed51fb9e4cc@emerson.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-20serial: 8250_dma: terminate correct DMA in tx_dma_flush()John Keeping
When flushing transmit side DMA, it is the transmit channel that should be terminated, not the receive channel. Fixes: 9e512eaaf8f40 ("serial: 8250: Fix fifo underflow on flush") Cc: stable <stable@kernel.org> Reported-by: Wentao Guan <guanwentao@uniontech.com> Signed-off-by: John Keeping <jkeeping@inmusicbrands.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20250224121831.1429323-1-jkeeping@inmusicbrands.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-20tty: serial: 8250: Add Brainboxes XC devicesCameron Williams
These ExpressCard devices use the OxPCIE chip and can be used with this driver. Signed-off-by: Cameron Williams <cang1@live.co.uk> Cc: stable <stable@kernel.org> Link: https://lore.kernel.org/r/DB7PR02MB3802907A9360F27F6CD67AAFC4D62@DB7PR02MB3802.eurprd02.prod.outlook.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-20tty: serial: 8250: Add some more device IDsCameron Williams
These card IDs got missed the first time around. Cc: stable <stable@kernel.org> Signed-off-by: Cameron Williams <cang1@live.co.uk> Link: https://lore.kernel.org/r/DB7PR02MB380295BCC879CCF91315AC38C4C12@DB7PR02MB3802.eurprd02.prod.outlook.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-20serial: 8250_dw: Comment possible corner cases in serial_out() implementationAndy Shevchenko
8250 DesignWare driver uses a few custom implementations of the serial_out(). These implementations are carefully made to avoid infinite loops. But this is not obvious from looking at the code. Comment the possible corner cases in the respective functions. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20250317094021.1201512-1-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-20serial: 8250_port: simplify serial8250_request_std_resource()Jiri Slaby (SUSE)
Return immediately from the error locations or switch-case ends. It is therefore easier to see the flow. Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org> Link: https://lore.kernel.org/r/20250317070046.24386-31-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-20serial: 8250_port: do not use goto for UPQ_NO_TXEN_TEST code flowJiri Slaby (SUSE)
This is unnecessary here and makes the code harder to follow. Invert the condition and drop the goto+label. Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org> Link: https://lore.kernel.org/r/20250317070046.24386-30-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-20serial: 8250_rsa: simplify rsa8250_{request/release}_resource()Jiri Slaby (SUSE)
* Use already defined 'port' for fetching start/offset, and size. * Return from the switch immediately -- so it is clear what is returned and when. Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org> Link: https://lore.kernel.org/r/20250317070046.24386-29-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-03-20serial: 8250: use serial_port_in/out() helpersJiri Slaby (SUSE)
There are serial_port_in/out() helpers to be used instead of direct p->serial_in/out(). Use them in various 8250 drivers. Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org> Cc: "Ilpo Järvinen" <ilpo.jarvinen@linux.intel.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> -- [v2] * Use serial_port_in/out() and not serial_in/out() [Andy] Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> # 8250_dw Link: https://lore.kernel.org/r/20250317070046.24386-28-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-20serial: 8250: Switch to use hrtimer_setup()Nam Cao
hrtimer_setup() takes the callback function pointer as argument and initializes the timer completely. Replace hrtimer_init() and the open coded initialization of hrtimer::function with the new setup mechanism. Patch was created by using Coccinelle. Acked-by: Zack Rusin <zack.rusin@broadcom.com> Signed-off-by: Nam Cao <namcao@linutronix.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://lore.kernel.org/r/991926d130cc272df30d226760d5d74187991669.1738746904.git.namcao@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-19serial: mctrl_gpio: split disable_ms into sync and no_sync APIsAlexis Lothoré
The following splat has been observed on a SAMA5D27 platform using atmel_serial: BUG: sleeping function called from invalid context at kernel/irq/manage.c:738 in_atomic(): 1, irqs_disabled(): 128, non_block: 0, pid: 27, name: kworker/u5:0 preempt_count: 1, expected: 0 INFO: lockdep is turned off. irq event stamp: 0 hardirqs last enabled at (0): [<00000000>] 0x0 hardirqs last disabled at (0): [<c01588f0>] copy_process+0x1c4c/0x7bec softirqs last enabled at (0): [<c0158944>] copy_process+0x1ca0/0x7bec softirqs last disabled at (0): [<00000000>] 0x0 CPU: 0 UID: 0 PID: 27 Comm: kworker/u5:0 Not tainted 6.13.0-rc7+ #74 Hardware name: Atmel SAMA5 Workqueue: hci0 hci_power_on [bluetooth] Call trace: unwind_backtrace from show_stack+0x18/0x1c show_stack from dump_stack_lvl+0x44/0x70 dump_stack_lvl from __might_resched+0x38c/0x598 __might_resched from disable_irq+0x1c/0x48 disable_irq from mctrl_gpio_disable_ms+0x74/0xc0 mctrl_gpio_disable_ms from atmel_disable_ms.part.0+0x80/0x1f4 atmel_disable_ms.part.0 from atmel_set_termios+0x764/0x11e8 atmel_set_termios from uart_change_line_settings+0x15c/0x994 uart_change_line_settings from uart_set_termios+0x2b0/0x668 uart_set_termios from tty_set_termios+0x600/0x8ec tty_set_termios from ttyport_set_flow_control+0x188/0x1e0 ttyport_set_flow_control from wilc_setup+0xd0/0x524 [hci_wilc] wilc_setup [hci_wilc] from hci_dev_open_sync+0x330/0x203c [bluetooth] hci_dev_open_sync [bluetooth] from hci_dev_do_open+0x40/0xb0 [bluetooth] hci_dev_do_open [bluetooth] from hci_power_on+0x12c/0x664 [bluetooth] hci_power_on [bluetooth] from process_one_work+0x998/0x1a38 process_one_work from worker_thread+0x6e0/0xfb4 worker_thread from kthread+0x3d4/0x484 kthread from ret_from_fork+0x14/0x28 This warning is emitted when trying to toggle, at the highest level, some flow control (with serdev_device_set_flow_control) in a device driver. At the lowest level, the atmel_serial driver is using serial_mctrl_gpio lib to enable/disable the corresponding IRQs accordingly. The warning emitted by CONFIG_DEBUG_ATOMIC_SLEEP is due to disable_irq (called in mctrl_gpio_disable_ms) being possibly called in some atomic context (some tty drivers perform modem lines configuration in regions protected by port lock). Split mctrl_gpio_disable_ms into two differents APIs, a non-blocking one and a blocking one. Replace mctrl_gpio_disable_ms calls with the relevant version depending on whether the call is protected by some port lock. Suggested-by: Jiri Slaby <jirislaby@kernel.org> Signed-off-by: Alexis Lothoré <alexis.lothore@bootlin.com> Acked-by: Richard Genoud <richard.genoud@bootlin.com> Link: https://lore.kernel.org/r/20250217-atomic_sleep_mctrl_serial_gpio-v3-1-59324b313eef@bootlin.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-17Merge 6.14-rc3 into tty-nextGreg Kroah-Hartman
We need the tty changes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-14serial: 8250_dw: Call dw8250_quirks() conditionallyAndy Shevchenko
Not all the cases provide the driver data, that is represented by an object instance of struct dw8250_platform_data. Id est the change missed the case when the driver is instantiated via board files as pure platform driver. Fix this by calling dw8250_quirks() conditionally. This will require splitting dw8250_setup_dma_filter() out of dw8250_quirks(). Also make sure IRQ handler won't crash, it also requires driver data to be present. Fixes: bfd3d4a40f39 ("serial: 8250_dw: Drop unneeded NULL checks in dw8250_quirks()") Reported-by: kernel test robot <oliver.sang@intel.com> Closes: https://lore.kernel.org/oe-lkp/202502121529.f7e65d49-lkp@intel.com Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20250212115952.2312444-1-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-14serial: 8250: Fix fifo underflow on flushJohn Keeping
When flushing the serial port's buffer, uart_flush_buffer() calls kfifo_reset() but if there is an outstanding DMA transfer then the completion function will consume data from the kfifo via uart_xmit_advance(), underflowing and leading to ongoing DMA as the driver tries to transmit another 2^32 bytes. This is readily reproduced with serial-generic and amidi sending even short messages as closing the device on exit will wait for the fifo to drain and in the underflow case amidi hangs for 30 seconds on exit in tty_wait_until_sent(). A trace of that gives: kworker/1:1-84 [001] 51.769423: bprint: serial8250_tx_dma: tx_size=3 fifo_len=3 amidi-763 [001] 51.769460: bprint: uart_flush_buffer: resetting fifo irq/21-fe530000-76 [000] 51.769474: bprint: __dma_tx_complete: tx_size=3 irq/21-fe530000-76 [000] 51.769479: bprint: serial8250_tx_dma: tx_size=4096 fifo_len=4294967293 irq/21-fe530000-76 [000] 51.781295: bprint: __dma_tx_complete: tx_size=4096 irq/21-fe530000-76 [000] 51.781301: bprint: serial8250_tx_dma: tx_size=4096 fifo_len=4294963197 irq/21-fe530000-76 [000] 51.793131: bprint: __dma_tx_complete: tx_size=4096 irq/21-fe530000-76 [000] 51.793135: bprint: serial8250_tx_dma: tx_size=4096 fifo_len=4294959101 irq/21-fe530000-76 [000] 51.804949: bprint: __dma_tx_complete: tx_size=4096 Since the port lock is held in when the kfifo is reset in uart_flush_buffer() and in __dma_tx_complete(), adding a flush_buffer hook to adjust the outstanding DMA byte count is sufficient to avoid the kfifo underflow. Fixes: 9ee4b83e51f74 ("serial: 8250: Add support for dmaengine") Cc: stable <stable@kernel.org> Signed-off-by: John Keeping <jkeeping@inmusicbrands.com> Link: https://lore.kernel.org/r/20250208124148.1189191-1-jkeeping@inmusicbrands.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-06Revert "serial: Airoha SoC UART and HSUART support"Greg Kroah-Hartman
This reverts commit e12ebf14fa3654f68589292e645ae1ef74786638. It causes build errors in linux-next. Cc: Benjamin Larsson <benjamin.larsson@genexis.eu> Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Link: https://lore.kernel.org/r/20250206135328.4bad1401@canb.auug.org.au Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-04serial: 8250_pnp: Remove unneeded ->iotype assignmentAndy Shevchenko
If ->iobase is set the default will be UPIO_PORT for ->iotype after the uart_read_and_validate_port_properties() call. Hence no need to assign that explicitly. Otherwise it will be UPIO_MEM. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20250124161530.398361-7-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-04serial: 8250_platform: Remove unneeded ->iotype assignmentAndy Shevchenko
If ->iobase is set the default will be UPIO_PORT for ->iotype after the uart_read_and_validate_port_properties() call. Hence no need to assign that explicitly. Otherwise it will be UPIO_MEM. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20250124161530.398361-6-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-04serial: 8250_of: Remove unneeded ->iotype assignmentAndy Shevchenko
If ->iobase is set the default will be UPIO_PORT for ->iotype after the uart_read_and_validate_port_properties() call. Hence no need to assign that explicitly. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20250124161530.398361-5-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-04serial: 8250_dw: Drop unneeded NULL checks in dw8250_quirks()Andy Shevchenko
Since platform data is being provided for all supported hardware, no need to NULL check for it. Drop unneeded checks. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20250203121456.3182891-1-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-04serial: Airoha SoC UART and HSUART supportBenjamin Larsson
Support for Airoha AN7581 SoC UART and HSUART baud rate calculation routine. Signed-off-by: Benjamin Larsson <benjamin.larsson@genexis.eu> Link: https://lore.kernel.org/r/20250119130105.2833517-3-benjamin.larsson@genexis.eu Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-22Revert "serial: 8250: Switch to nbcon console"Greg Kroah-Hartman
This reverts commit b63e6f60eab45b16a1bf734fef9035a4c4187cd5. kernel test robot has found problems with this commit so revert it for now. Link: https://lore.kernel.org/r/202501221029.fb0d574d-lkp@intel.com Reported-by: kernel test robot <oliver.sang@intel.com> Closes: https://lore.kernel.org/oe-lkp/202501221029.fb0d574d-lkp@intel.com Cc: John Ogness <john.ogness@linutronix.de> Cc: Petr Mladek <pmladek@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-22Revert "serial: 8250: Revert "drop lockdep annotation from ↵Greg Kroah-Hartman
serial8250_clear_IER()"" This reverts commit 422c9727b07f9f86e2ec11c56622e566221591cc. kernel test robot has found problems with this commit so revert it for now. Link: https://lore.kernel.org/r/202501221029.fb0d574d-lkp@intel.com Reported-by: kernel test robot <oliver.sang@intel.com> Closes: https://lore.kernel.org/oe-lkp/202501221029.fb0d574d-lkp@intel.com Cc: John Ogness <john.ogness@linutronix.de> Cc: Petr Mladek <pmladek@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-13Merge 6.13-rc7 into tty-nextGreg Kroah-Hartman
We need the serial driver fixes in here to build on top of. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-10serial: 8250: Revert "drop lockdep annotation from serial8250_clear_IER()"John Ogness
The 8250 driver no longer depends on @oops_in_progress and will no longer violate the port->lock locking constraints. This reverts commit 3d9e6f556e235ddcdc9f73600fdd46fe1736b090. Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20250107212702.169493-7-john.ogness@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-10serial: 8250: Switch to nbcon consoleJohn Ogness
Implement the necessary callbacks to switch the 8250 console driver to perform as an nbcon console. Add implementations for the nbcon console callbacks: ->write_atomic() ->write_thread() ->device_lock() ->device_unlock() and add CON_NBCON to the initial @flags. All register access in the callbacks are within unsafe sections. The ->write_atomic() and ->write_thread() callbacks allow safe handover/takeover per byte and add a preceding newline if they take over from another context mid-line. For the ->write_atomic() callback, a new irq_work is used to defer modem control since it may be called from a context that does not allow waking up tasks. Note: A new __serial8250_clear_IER() is introduced for direct clearing of UART_IER. This will allow to restore the lockdep check to serial8250_clear_IER() in a follow-up commit. Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Petr Mladek <pmladek@suse.com> Tested-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20250107212702.169493-6-john.ogness@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-10serial: 8250: Provide flag for IER toggling for RS485John Ogness
For RS485 mode, if SER_RS485_RX_DURING_TX is not available, the console ->write() callback needs to enable/disable Tx. It does this by calling the ->rs485_start_tx() and ->rs485_stop_tx() callbacks. However, some of these callbacks also disable/enable interrupts and makes power management calls. This causes 2 problems for console writing: 1. A console write can occur in contexts that are illegal for pm_runtime_*(). It is not even necessary for console writing to use pm_runtime_*() because a console already does this in serial8250_console_setup() and serial8250_console_exit(). 2. The console ->write() callback already handles disabling/enabling the interrupts by properly restoring the previous IER value. Add an argument @toggle_ier to the ->rs485_start_tx() and ->rs485_stop_tx() callbacks to specify if they may disable/enable receive interrupts while using pm_runtime_*(). Console writing will not allow the toggling. For all call sites other than console writing there is no functional change. Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20250107212702.169493-5-john.ogness@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-10serial: 8250: Use high-level writing function for FIFOJohn Ogness
Currently serial8250_console_fifo_write() directly writes into the UART_TX register rather than using the high-level function serial8250_console_putchar(). This is because serial8250_console_putchar() waits for the holding register to become empty, which would defeat the purpose of the FIFO code. Move the LSR_THRE waiting to a new function serial8250_console_wait_putchar() so that the FIFO code can use serial8250_console_putchar(). This will be particularly important for a follow-up commit, where output bytes are inspected to track newlines. This is only refactoring and has no functional change. Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20250107212702.169493-4-john.ogness@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-10serial: 8250: Use frame time to determine timeoutJohn Ogness
Rather than using a hard-coded per-character Tx-timeout of 10ms, use the frame time to determine a timeout value. The value is doubled to ensure that a timeout is only hit during unexpected circumstances. Since the frame time may not be available during early printing, the previous 10ms value is kept as a fallback. Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20250107212702.169493-3-john.ogness@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-10serial: 8250: Adjust the timeout for FIFO modeJohn Ogness
After a console has written a record into UART_TX, it uses wait_for_xmitr() to wait until the data has been sent out before returning. However, wait_for_xmitr() will timeout after 10ms, regardless if the data has been transmitted or not. For single bytes, this timeout is sufficient even at very slow baud rates, such as 1200bps. However, when FIFO mode is used, there may be 64 bytes pushed into the FIFO at once. At a baud rate of 115200bps, the 10ms timeout is still sufficient. But when using lower baud rates (such as 57600bps), the timeout is _not_ sufficient. This causes longer lines to be cut off, resulting in lost and horribly misformatted output on the console. When using FIFO mode, take the number of bytes into account to determine an appropriate maximum timeout. Increasing the timeout does not affect performance since ideally the timeout never occurs. Fixes: 8f3631f0f6eb ("serial/8250: Use fifo in 8250 console driver") Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Wander Lairson Costa <wander@redhat.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20250107212702.169493-2-john.ogness@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-23tty: serial: 8250: Fix another runtime PM usage counter underflowIlpo Järvinen
The commit f9b11229b79c ("serial: 8250: Fix PM usage_count for console handover") fixed one runtime PM usage counter balance problem that occurs because .dev is not set during univ8250 setup preventing call to pm_runtime_get_sync(). Later, univ8250_console_exit() will trigger the runtime PM usage counter underflow as .dev is already set at that time. Call pm_runtime_get_sync() to balance the RPM usage counter also in serial8250_register_8250_port() before trying to add the port. Reported-by: Borislav Petkov (AMD) <bp@alien8.de> Fixes: bedb404e91bb ("serial: 8250_port: Don't use power management for kernel console") Cc: stable <stable@kernel.org> Tested-by: Borislav Petkov (AMD) <bp@alien8.de> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20241210170120.2231-1-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-23serial: 8250: Explain the role of @read_status_maskJohn Ogness
The role of @read_status_mask has changed over time and seems to still cause confusion. This can be expected since there is zero documentation about this driver-specific variable. Add comments to the initialization of @read_status_mask to clarify its role. Signed-off-by: John Ogness <john.ogness@linutronix.de> Link: https://lore.kernel.org/r/20241216171244.12783-5-john.ogness@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-23serial: 8250: Never adjust UART_LSR_DR in @read_status_maskJohn Ogness
The CREAD feature of termios is implemented by setting/clearing UART_LSR_DR within @ignore_status_mask. For this feature to function correctly, it requires that UART_LSR_DR is never masked (unset) in @read_status_mask so that uart_insert_char() can properly drop the character if CREAD is disabled. Currently there are code paths that clear/set UART_LSR_DR from @read_status_mask at times. This appears to be a relic from Linux 1.1.60, where @read_status_mask could be used to mask all UART_LSR reading. However, since Linux 2.1.8 that is no longer the case. Now if UART_LSR_DR is cleared from @read_status_mask, received characters may not be dropped even though CREAD is disabled. This can be seen when: - CREAD is disabled (UART_LSR_DR is set in @ignore_status_mask) - LSR has an error bit set from UART_LSR_BRK_ERROR_BITS (and that error is not ignored via @ignore_status_mask) - UART_LSR_DR is cleared in @read_status_mask In this case characters will be inserted into the tty buffer even though they should be ignored. Remove all setting/clearing of UART_LSR_DR for @read_status_mask except for its initialization. Signed-off-by: John Ogness <john.ogness@linutronix.de> Link: https://lore.kernel.org/r/20241216171244.12783-4-john.ogness@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-23serial: 8250: Do not set UART_LSR_THRE in @read_status_maskJohn Ogness
Since Linux 2.1.8 @read_status_mask is no longer used as a general control of which bits are used from the LSR register. Instead it has become an additional mask applied to @ignore_status_mask. Since UART_LSR_THRE is never set for @ignore_status_mask, it serves no purpose to set it for @read_status_mask. In fact, it propagates the misconception that @read_status_mask can be used as a general mask for LSR bits. Do not set UART_LSR_THRE for @read_status_mask. Signed-off-by: John Ogness <john.ogness@linutronix.de> Link: https://lore.kernel.org/r/20241216171244.12783-3-john.ogness@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-23serial: 8250: Use @ier bits to determine if Rx is stoppedJohn Ogness
Commit f19c3f6c8109 ("serial: 8250_port: Don't service RX FIFO if throttled") uses @read_status_mask (bit UART_LSR_DR) to determine if Rx has been stopped. However, the bit UART_LSR_DR is not managed properly in @read_status_mask for all Rx stop/start situations and is therefore not suitable for this purpose. Use the UART_IER_RLSI and UART_IER_RDI bits in @ier instead, as this is already common in 8250-variants and drivers. Signed-off-by: John Ogness <john.ogness@linutronix.de> Link: https://lore.kernel.org/r/20241216171244.12783-2-john.ogness@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-238250: microchip: pci1xxxx: Add workaround for RTS bit toggleRengarajan S
In the B0 revision, the RTS pin remains high due to incorrect hardware mapping. To address this issue, enable auto-direction control with the RTS bit in ADCL_CFG_REG. This configuration ensures that the RTS pin goes low when the terminal is opened and high when the terminal is closed. Additionally, we reset the step counter for Rx and Tx engines by writing into FRAC_DIV_CFG_REG. Signed-off-by: Rengarajan S <rengarajan.s@microchip.com> Link: https://lore.kernel.org/r/20241218094017.18290-1-rengarajan.s@microchip.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
generated by cgit (git 2.34.1) at 2025-07-29 17:47:15 +0000