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path: root/drivers/tty/serial/8250
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2024-03-26serial: 8250_exar: Don't remove GPIO device on suspendAndy Shevchenko
[ Upstream commit 73b5a5c00be39e23b194bad10e1ea8bb73eee176 ] It seems a copy&paste mistake that suspend callback removes the GPIO device. There is no counterpart of this action, means once suspended there is no more GPIO device available untile full unbind-bind cycle is performed. Remove suspicious GPIO device removal in suspend. Fixes: d0aeaa83f0b0 ("serial: exar: split out the exar code from 8250_pci") Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20240219150627.2101198-2-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-25serial: 8250: omap: Don't skip resource freeing if ↵Uwe Kleine-König
pm_runtime_resume_and_get() failed [ Upstream commit ad90d0358bd3b4554f243a425168fc7cebe7d04e ] Returning an error code from .remove() makes the driver core emit the little helpful error message: remove callback returned a non-zero value. This will be ignored. and then remove the device anyhow. So all resources that were not freed are leaked in this case. Skipping serial8250_unregister_port() has the potential to keep enough of the UART around to trigger a use-after-free. So replace the error return (and with it the little helpful error message) by a more useful error message and continue to cleanup. Fixes: e3f0c638f428 ("serial: 8250: omap: Fix unpaired pm_runtime_put_sync() in omap8250_remove()") Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Reviewed-by: Tony Lindgren <tony@atomide.com> Link: https://lore.kernel.org/r/20231110152927.70601-2-u.kleine-koenig@pengutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-12-13serial: 8250_omap: Add earlycon support for the AM654 UART controllerRonald Wahl
commit 8e42c301ce64e0dcca547626eb486877d502d336 upstream. Currently there is no support for earlycon on the AM654 UART controller. This commit adds it. Signed-off-by: Ronald Wahl <ronald.wahl@raritan.com> Reviewed-by: Vignesh Raghavendra <vigneshr@ti.com> Link: https://lore.kernel.org/r/20231031131242.15516-1-rwahl@gmx.de Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-08tty: 8250: Add support for Intashield IS-100Cameron Williams
commit 4d994e3cf1b541ff32dfb03fbbc60eea68f9645b upstream. Add support for the Intashield IS-100 1 port serial card. Cc: stable@vger.kernel.org Signed-off-by: Cameron Williams <cang1@live.co.uk> Link: https://lore.kernel.org/r/DU0PR02MB7899A0E0CDAA505AF5A874CDC4DBA@DU0PR02MB7899.eurprd02.prod.outlook.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-08tty: 8250: Add support for Brainboxes UP cardsCameron Williams
commit 2c6fec1e1532f15350be7e14ba6b88a39d289fe4 upstream. Add support for the Brainboxes UP (powered PCI) range of cards, namely UP-189, UP-200, UP-869 and UP-880. Cc: stable@vger.kernel.org Signed-off-by: Cameron Williams <cang1@live.co.uk> Link: https://lore.kernel.org/r/DU0PR02MB7899B5B59FF3D8587E88C117C4DBA@DU0PR02MB7899.eurprd02.prod.outlook.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-08tty: 8250: Add support for additional Brainboxes UC cardsCameron Williams
commit c563db486db7d245c0e2f319443417ae8e692f7f upstream. Add device IDs for some more Brainboxes UC cards, namely UC-235/UC-246, UC-253/UC-734, UC-302, UC-313, UC-346, UC-357, UC-607 and UC-836. Cc: stable@vger.kernel.org Signed-off-by: Cameron Williams <cang1@live.co.uk> Link: https://lore.kernel.org/r/DU0PR02MB789969998A6C3FAFCD95C85DC4DBA@DU0PR02MB7899.eurprd02.prod.outlook.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-08tty: 8250: Remove UC-257 and UC-431Cameron Williams
commit 33092fb3af51deb80849e90a17bada44bbcde6b3 upstream. The UC-257 is a serial + LPT card, so remove it from this driver. A patch has been submitted to add it to parport_serial instead. Additionaly, the UC-431 does not use this card ID, only the UC-420 does. The 431 is a 3-port card and there is no generic 3-port configuration available, so remove reference to it from this driver. Fixes: 152d1afa834c ("tty: Add support for Brainboxes UC cards.") Cc: stable@vger.kernel.org Signed-off-by: Cameron Williams <cang1@live.co.uk> Link: https://lore.kernel.org/r/DU0PR02MB78995ADF7394C74AD4CF3357C4DBA@DU0PR02MB7899.eurprd02.prod.outlook.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-10serial: 8250_port: Check IRQ data before useAndy Shevchenko
commit cce7fc8b29961b64fadb1ce398dc5ff32a79643b upstream. In case the leaf driver wants to use IRQ polling (irq = 0) and IIR register shows that an interrupt happened in the 8250 hardware the IRQ data can be NULL. In such a case we need to skip the wake event as we came to this path from the timer interrupt and quite likely system is already awake. Without this fix we have got an Oops: serial8250: ttyS0 at I/O 0x3f8 (irq = 0, base_baud = 115200) is a 16550A ... BUG: kernel NULL pointer dereference, address: 0000000000000010 RIP: 0010:serial8250_handle_irq+0x7c/0x240 Call Trace: ? serial8250_handle_irq+0x7c/0x240 ? __pfx_serial8250_timeout+0x10/0x10 Fixes: 0ba9e3a13c6a ("serial: 8250: Add missing wakeup event reporting") Cc: stable <stable@kernel.org> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com> Link: https://lore.kernel.org/r/20230831222555.614426-1-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-30serial: 8250: Fix oops for port->pm on uart_change_pm()Tony Lindgren
[ Upstream commit dfe2aeb226fd5e19b0ee795f4f6ed8bc494c1534 ] Unloading a hardware specific 8250 driver can produce error "Unable to handle kernel paging request at virtual address" about ten seconds after unloading the driver. This happens on uart_hangup() calling uart_change_pm(). Turns out commit 04e82793f068 ("serial: 8250: Reinit port->pm on port specific driver unbind") was only a partial fix. If the hardware specific driver has initialized port->pm function, we need to clear port->pm too. Just reinitializing port->ops does not do this. Otherwise serial8250_pm() will call port->pm() instead of serial8250_do_pm(). Fixes: 04e82793f068 ("serial: 8250: Reinit port->pm on port specific driver unbind") Signed-off-by: Tony Lindgren <tony@atomide.com> Link: https://lore.kernel.org/r/20230804131553.52927-1-tony@atomide.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-08-11serial: 8250_dw: Preserve original value of DLF registerRuihong Luo
commit 748c5ea8b8796ae8ee80b8d3a3d940570b588d59 upstream. Preserve the original value of the Divisor Latch Fraction (DLF) register. When the DLF register is modified without preservation, it can disrupt the baudrate settings established by firmware or bootloader, leading to data corruption and the generation of unreadable or distorted characters. Fixes: 701c5e73b296 ("serial: 8250_dw: add fractional divisor support") Cc: stable <stable@kernel.org> Signed-off-by: Ruihong Luo <colorsu1922@gmail.com> Link: https://lore.kernel.org/stable/20230713004235.35904-1-colorsu1922%40gmail.com Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20230713004235.35904-1-colorsu1922@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-27Revert "8250: add support for ASIX devices with a FIFO bug"Jiaqing Zhao
commit a82d62f708545d22859584e0e0620da8e3759bbc upstream. This reverts commit eb26dfe8aa7eeb5a5aa0b7574550125f8aa4c3b3. Commit eb26dfe8aa7e ("8250: add support for ASIX devices with a FIFO bug") merged on Jul 13, 2012 adds a quirk for PCI_VENDOR_ID_ASIX (0x9710). But that ID is the same as PCI_VENDOR_ID_NETMOS defined in 1f8b061050c7 ("[PATCH] Netmos parallel/serial/combo support") merged on Mar 28, 2005. In pci_serial_quirks array, the NetMos entry always takes precedence over the ASIX entry even since it was initially merged, code in that commit is always unreachable. In my tests, adding the FIFO workaround to pci_netmos_init() makes no difference, and the vendor driver also does not have such workaround. Given that the code was never used for over a decade, it's safe to revert it. Also, the real PCI_VENDOR_ID_ASIX should be 0x125b, which is used on their newer AX99100 PCIe serial controllers released on 2016. The FIFO workaround should not be intended for these newer controllers, and it was never implemented in vendor driver. Fixes: eb26dfe8aa7e ("8250: add support for ASIX devices with a FIFO bug") Cc: stable <stable@kernel.org> Signed-off-by: Jiaqing Zhao <jiaqing.zhao@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20230619155743.827859-1-jiaqing.zhao@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-27serial: 8250_omap: Use force_suspend and resume for system suspendTony Lindgren
[ Upstream commit 20a41a62618df85f3a2981008edec5cadd785e0a ] We should not rely on autosuspend timeout for system suspend. Instead, let's use force_suspend and force_resume functions. Otherwise the serial port controller device may not be idled on suspend. As we are doing a register write on suspend to configure the serial port, we still need to runtime PM resume the port on suspend. While at it, let's switch to pm_runtime_resume_and_get() and check for errors returned. And let's add the missing line break before return to the suspend function while at it. Fixes: 09d8b2bdbc5c ("serial: 8250: omap: Provide ability to enable/disable UART as wakeup source") Signed-off-by: Tony Lindgren <tony@atomide.com> Tested-by: Dhruva Gole <d-gole@ti.com> Message-ID: <20230614045922.4798-1-tony@atomide.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-30serial: Add support for Advantech PCI-1611U cardVitaliy Tomin
commit d2b00516de0e1d696724247098f6733a6ea53908 upstream. Add support for Advantech PCI-1611U card Advantech provides opensource drivers for this and many others card based on legacy copy of 8250_pci driver called adv950 https://www.advantech.com/emt/support/details/driver?id=1-TDOIMJ It is hard to maintain to run as out of tree module on newer kernels. Just adding PCI ID to kernel 8250_pci works perfect. Signed-off-by: Vitaliy Tomin <tomin@iszf.irk.ru> Cc: stable <stable@kernel.org> Link: https://lore.kernel.org/r/20230423034512.2671157-1-tomin@iszf.irk.ru Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-30serial: 8250: Reinit port->pm on port specific driver unbindTony Lindgren
[ Upstream commit 04e82793f068d2f0ffe62fcea03d007a8cdc16a7 ] When we unbind a serial port hardware specific 8250 driver, the generic serial8250 driver takes over the port. After that we see an oops about 10 seconds later. This can produce the following at least on some TI SoCs: Unhandled fault: imprecise external abort (0x1406) Internal error: : 1406 [#1] SMP ARM Turns out that we may still have the serial port hardware specific driver port->pm in use, and serial8250_pm() tries to call it after the port specific driver is gone: serial8250_pm [8250_base] from uart_change_pm+0x54/0x8c [serial_base] uart_change_pm [serial_base] from uart_hangup+0x154/0x198 [serial_base] uart_hangup [serial_base] from __tty_hangup.part.0+0x328/0x37c __tty_hangup.part.0 from disassociate_ctty+0x154/0x20c disassociate_ctty from do_exit+0x744/0xaac do_exit from do_group_exit+0x40/0x8c do_group_exit from __wake_up_parent+0x0/0x1c Let's fix the issue by calling serial8250_set_defaults() in serial8250_unregister_port(). This will set the port back to using the serial8250 default functions, and sets the port->pm to point to serial8250_pm. Signed-off-by: Tony Lindgren <tony@atomide.com> Link: https://lore.kernel.org/r/20230418101407.12403-1-tony@atomide.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-17serial: 8250: Fix serial8250_tx_empty() race with DMA TxIlpo Järvinen
There's a potential race before THRE/TEMT deasserts when DMA Tx is starting up (or the next batch of continuous Tx is being submitted). This can lead to misdetecting Tx empty condition. It is entirely normal for THRE/TEMT to be set for some time after the DMA Tx had been setup in serial8250_tx_dma(). As Tx side is definitely not empty at that point, it seems incorrect for serial8250_tx_empty() claim Tx is empty. Fix the race by also checking in serial8250_tx_empty() whether there's DMA Tx active. Note: This fix only addresses in-kernel race mainly to make using TCSADRAIN/FLUSH robust. Userspace can still cause other races but they seem userspace concurrency control problems. Fixes: 9ee4b83e51f74 ("serial: 8250: Add support for dmaengine") Cc: stable@vger.kernel.org Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20230317113318.31327-3-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> (cherry picked from commit 146a37e05d620cef4ad430e5d1c9c077fe6fa76f) Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-17serial: 8250: Add missing wakeup event reportingFlorian Fainelli
[ Upstream commit 0ba9e3a13c6adfa99e32b2576d20820ab10ad48a ] An 8250 UART configured as a wake-up source would not have reported itself through sysfs as being the source of wake-up, correct that. Fixes: b3b708fa2780 ("wake up from a serial port") Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Link: https://lore.kernel.org/r/20230414170241.2016255-1-f.fainelli@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-03-22serial: 8250_em: Fix UART port typeBiju Das
commit 32e293be736b853f168cd065d9cbc1b0c69f545d upstream. As per HW manual for EMEV2 "R19UH0040EJ0400 Rev.4.00", the UART IP found on EMMA mobile SoC is Register-compatible with the general-purpose 16750 UART chip. Fix UART port type as 16750 and enable 64-bytes fifo support. Fixes: 22886ee96895 ("serial8250-em: Emma Mobile UART driver V2") Cc: stable@vger.kernel.org Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com> Link: https://lore.kernel.org/r/20230227114152.22265-2-biju.das.jz@bp.renesas.com [biju: manually fixed the conflicts] Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-02-22serial: 8250_dma: Fix DMA Rx rearm raceIlpo Järvinen
commit 57e9af7831dcf211c5c689c2a6f209f4abdf0bce upstream. As DMA Rx can be completed from two places, it is possible that DMA Rx completes before DMA completion callback had a chance to complete it. Once the previous DMA Rx has been completed, a new one can be started on the next UART interrupt. The following race is possible (uart_unlock_and_check_sysrq_irqrestore() replaced with spin_unlock_irqrestore() for simplicity/clarity): CPU0 CPU1 dma_rx_complete() serial8250_handle_irq() spin_lock_irqsave(&port->lock) handle_rx_dma() serial8250_rx_dma_flush() __dma_rx_complete() dma->rx_running = 0 // Complete DMA Rx spin_unlock_irqrestore(&port->lock) serial8250_handle_irq() spin_lock_irqsave(&port->lock) handle_rx_dma() serial8250_rx_dma() dma->rx_running = 1 // Setup a new DMA Rx spin_unlock_irqrestore(&port->lock) spin_lock_irqsave(&port->lock) // sees dma->rx_running = 1 __dma_rx_complete() dma->rx_running = 0 // Incorrectly complete // running DMA Rx This race seems somewhat theoretical to occur for real but handle it correctly regardless. Check what is the DMA status before complething anything in __dma_rx_complete(). Reported-by: Gilles BULOZ <gilles.buloz@kontron.com> Tested-by: Gilles BULOZ <gilles.buloz@kontron.com> Fixes: 9ee4b83e51f7 ("serial: 8250: Add support for dmaengine") Cc: stable@vger.kernel.org Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20230130114841.25749-3-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-02-22serial: 8250_dma: Fix DMA Rx completion raceIlpo Järvinen
commit 31352811e13dc2313f101b890fd4b1ce760b5fe7 upstream. __dma_rx_complete() is called from two places: - Through the DMA completion callback dma_rx_complete() - From serial8250_rx_dma_flush() after IIR_RLSI or IIR_RX_TIMEOUT The former does not hold port's lock during __dma_rx_complete() which allows these two to race and potentially insert the same data twice. Extend port's lock coverage in dma_rx_complete() to prevent the race and check if the DMA Rx is still pending completion before calling into __dma_rx_complete(). Reported-by: Gilles BULOZ <gilles.buloz@kontron.com> Tested-by: Gilles BULOZ <gilles.buloz@kontron.com> Fixes: 9ee4b83e51f7 ("serial: 8250: Add support for dmaengine") Cc: stable@vger.kernel.org Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20230130114841.25749-2-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-12-08serial: 8250: 8250_omap: Avoid RS485 RTS glitch on ->set_termios()Lukas Wunner
[ Upstream commit 038ee49fef18710bedd38b531d173ccd746b2d8d ] RS485-enabled UART ports on TI Sitara SoCs with active-low polarity exhibit a Transmit Enable glitch on ->set_termios(): omap8250_restore_regs(), which is called from omap_8250_set_termios(), sets the TCRTLR bit in the MCR register and clears all other bits, including RTS. If RTS uses active-low polarity, it is now asserted for no reason. The TCRTLR bit is subsequently cleared by writing up->mcr to the MCR register. That variable is always zero, so the RTS bit is still cleared (incorrectly so if RTS is active-high). (up->mcr is not, as one might think, a cache of the MCR register's current value. Rather, it only caches a single bit of that register, the AFE bit. And it only does so if the UART supports the AFE bit, which OMAP does not. For details see serial8250_do_set_termios() and serial8250_do_set_mctrl().) Finally at the end of omap8250_restore_regs(), the MCR register is restored (and RTS deasserted) by a call to up->port.ops->set_mctrl() (which equals serial8250_set_mctrl()) and serial8250_em485_stop_tx(). So there's an RTS glitch between setting TCRTLR and calling serial8250_em485_stop_tx(). Avoid by using a read-modify-write when setting TCRTLR. While at it, drop a redundant initialization of up->mcr. As explained above, the variable isn't used by the driver and it is already initialized to zero because it is part of the static struct serial8250_ports[] declared in 8250_core.c. (Static structs are initialized to zero per section 6.7.8 nr. 10 of the C99 standard.) Cc: Jan Kiszka <jan.kiszka@siemens.com> Cc: Su Bao Cheng <baocheng.su@siemens.com> Tested-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com> Signed-off-by: Lukas Wunner <lukas@wunner.de> Link: https://lore.kernel.org/r/6554b0241a2c7fd50f32576fdbafed96709e11e8.1664278942.git.lukas@wunner.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-25serial: 8250: Flush DMA Rx on RLSIIlpo Järvinen
commit 1980860e0c8299316cddaf0992dd9e1258ec9d88 upstream. Returning true from handle_rx_dma() without flushing DMA first creates a data ordering hazard. If DMA Rx has handled any character at the point when RLSI occurs, the non-DMA path handles any pending characters jumping them ahead of those characters that are pending under DMA. Fixes: 75df022b5f89 ("serial: 8250_dma: Fix RX handling") Cc: <stable@vger.kernel.org> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20221108121952.5497-5-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-25serial: 8250_lpss: Configure DMA also w/o DMA filterIlpo Järvinen
commit 1bfcbe5805d0cfc83c3544dcd01e0a282c1f6790 upstream. If the platform doesn't use DMA device filter (as is the case with Elkhart Lake), whole lpss8250_dma_setup() setup is skipped. This results in skipping also *_maxburst setup which is undesirable. Refactor lpss8250_dma_setup() to configure DMA even if filter is not setup. Cc: stable <stable@kernel.org> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20221108121952.5497-3-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-25serial: 8250: Fall back to non-DMA Rx if IIR_RDI occursIlpo Järvinen
commit a931237cbea256aff13bb403da13a97b2d1605d9 upstream. DW UART sometimes triggers IIR_RDI during DMA Rx when IIR_RX_TIMEOUT should have been triggered instead. Since IIR_RDI has higher priority than IIR_RX_TIMEOUT, this causes the Rx to hang into interrupt loop. The problem seems to occur at least with some combinations of small-sized transfers (I've reproduced the problem on Elkhart Lake PSE UARTs). If there's already an on-going Rx DMA and IIR_RDI triggers, fall graciously back to non-DMA Rx. That is, behave as if IIR_RX_TIMEOUT had occurred. 8250_omap already considers IIR_RDI similar to this change so its nothing unheard of. Fixes: 75df022b5f89 ("serial: 8250_dma: Fix RX handling") Cc: <stable@vger.kernel.org> Co-developed-by: Srikanth Thokala <srikanth.thokala@intel.com> Signed-off-by: Srikanth Thokala <srikanth.thokala@intel.com> Co-developed-by: Aman Kumar <aman.kumar@intel.com> Signed-off-by: Aman Kumar <aman.kumar@intel.com> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20221108121952.5497-2-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-25serial: 8250: omap: Flush PM QOS work on removeTony Lindgren
[ Upstream commit d0b68629bd2fb61e0171a62f2e8da3db322f5cf6 ] Rebinding 8250_omap in a loop will at some point produce a warning for kernel/power/qos.c:296 cpu_latency_qos_update_request() with error "cpu_latency_qos_update_request called for unknown object". Let's flush the possibly pending PM QOS work scheduled from omap8250_runtime_suspend() before we disable runtime PM. Fixes: 61929cf0169d ("tty: serial: Add 8250-core based omap driver") Signed-off-by: Tony Lindgren <tony@atomide.com> Link: https://lore.kernel.org/r/20221028110044.54719-1-tony@atomide.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-25serial: 8250: omap: Fix unpaired pm_runtime_put_sync() in omap8250_remove()Tony Lindgren
[ Upstream commit e3f0c638f428fd66b5871154b62706772045f91a ] On remove, we get an error for "Runtime PM usage count underflow!". I guess this driver is mostly built-in, and this issue has gone unnoticed for a while. Somehow I did not catch this issue with my earlier fix done with commit 4e0f5cc65098 ("serial: 8250_omap: Fix probe and remove for PM runtime"). Fixes: 4e0f5cc65098 ("serial: 8250_omap: Fix probe and remove for PM runtime") Signed-off-by: Tony Lindgren <tony@atomide.com> Depends-on: dd8088d5a896 ("PM: runtime: Add pm_runtime_resume_and_get to deal with usage counter") Link: https://lore.kernel.org/r/20221028105813.54290-1-tony@atomide.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-25serial: 8250_omap: remove wait loop from Errata i202 workaroundMatthias Schiffer
[ Upstream commit e828e56684d61b17317e0cfdef83791fa61cb76b ] We were occasionally seeing the "Errata i202: timedout" on an AM335x board when repeatedly opening and closing a UART connected to an active sender. As new input may arrive at any time, it is possible to miss the "RX FIFO empty" condition, forcing the loop to wait until it times out. Nothing in the i202 Advisory states that such a wait is even necessary; other FIFO clear functions like serial8250_clear_fifos() do not wait either. For this reason, it seems safe to remove the wait, fixing the mentioned issue. Fixes: 61929cf0169d ("tty: serial: Add 8250-core based omap driver") Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com> Link: https://lore.kernel.org/r/20221013112339.2540767-1-matthias.schiffer@ew.tq-group.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-10parisc: Make 8250_gsc driver dependend on CONFIG_PARISCHelge Deller
commit e8a18e3f00f3ee8d07c17ab1ea3ad4df4a3b6fe0 upstream. Although the name of the driver 8250_gsc.c suggests that it handles only serial ports on the GSC bus, it does handle serial ports listed in the parisc machine inventory as well, e.g. the serial ports in a C8000 PCI-only workstation. Change the dependency to CONFIG_PARISC, so that the driver gets included in the kernel even if CONFIG_GSC isn't set. Reported-by: Mikulas Patocka <mpatocka@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: Helge Deller <deller@gmx.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-10-26serial: 8250: Fix restoring termios speed after suspendPali Rohár
[ Upstream commit 379a33786d489ab81885ff0b3935cfeb36137fea ] Since commit edc6afc54968 ("tty: switch to ktermios and new framework") termios speed is no longer stored only in c_cflag member but also in new additional c_ispeed and c_ospeed members. If BOTHER flag is set in c_cflag then termios speed is stored only in these new members. Since commit 027b57170bf8 ("serial: core: Fix initializing and restoring termios speed") termios speed is available also in struct console. So properly restore also c_ispeed and c_ospeed members after suspend to fix restoring termios speed which is not represented by Bnnn constant. Fixes: 4516d50aabed ("serial: 8250: Use canary to restart console after suspend") Signed-off-by: Pali Rohár <pali@kernel.org> Link: https://lore.kernel.org/r/20220924104324.4035-1-pali@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-25serial: 8250_dw: Store LSR into lsr_saved_flags in dw8250_tx_wait_empty()Ilpo Järvinen
[ Upstream commit af14f3007e2dca0d112f10f6717ba43093f74e81 ] Make sure LSR flags are preserved in dw8250_tx_wait_empty(). This function is called from a low-level out function and therefore cannot call serial_lsr_in() as it would lead to infinite recursion. It is borderline if the flags need to be saved here at all since this code relates to writing LCR register which usually implies no important characters should be arriving. Fixes: 914eaf935ec7 ("serial: 8250_dw: Allow TX FIFO to drain before writing to UART_LCR") Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20220608095431.18376-7-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-07-21serial: 8250: fix return error code in serial8250_request_std_resource()Yi Yang
commit 6e690d54cfa802f939cefbd2fa2c91bd0b8bd1b6 upstream. If port->mapbase = NULL in serial8250_request_std_resource() , it need return a error code instead of 0. If uart_set_info() fail to request new regions by serial8250_request_std_resource() but the return value of serial8250_request_std_resource() is 0, The system incorrectly considers that the resource application is successful and does not attempt to restore the old setting. A null pointer reference is triggered when the port resource is later invoked. Signed-off-by: Yi Yang <yiyang13@huawei.com> Cc: stable <stable@kernel.org> Link: https://lore.kernel.org/r/20220628083515.64138-1-yiyang13@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-06-22serial: 8250: Store to lsr_save_flags after lsr readIlpo Järvinen
commit be03b0651ffd8bab69dfd574c6818b446c0753ce upstream. Not all LSR register flags are preserved across reads. Therefore, LSR readers must store the non-preserved bits into lsr_save_flags. This fix was initially mixed into feature commit f6f586102add ("serial: 8250: Handle UART without interrupt on TEMT using em485"). However, that feature change had a flaw and it was reverted to make room for simpler approach providing the same feature. The embedded fix got reverted with the feature change. Re-add the lsr_save_flags fix and properly mark it's a fix. Link: https://lore.kernel.org/all/1d6c31d-d194-9e6a-ddf9-5f29af829f3@linux.intel.com/T/#m1737eef986bd20cf19593e344cebd7b0244945fc Fixes: e490c9144cfa ("tty: Add software emulated RS485 support for 8250") Cc: stable <stable@kernel.org> Acked-by: Uwe Kleine-König <u.kleine-koenig@penugtronix.de> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/f4d774be-1437-a550-8334-19d8722ab98c@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-06-14serial: 8250_fintek: Check SER_RS485_RTS_* only with RS485Ilpo Järvinen
[ Upstream commit af0179270977508df6986b51242825d7edd59caf ] SER_RS485_RTS_ON_SEND and SER_RS485_RTS_AFTER_SEND relate to behavior within RS485 operation. The driver checks if they have the same value which is not possible to realize with the hardware. The check is taken regardless of SER_RS485_ENABLED flag and -EINVAL is returned when the check fails, which creates problems. This check makes it unnecessarily complicated to turn RS485 mode off as simple zeroed serial_rs485 struct will trigger that equal values check. In addition, the driver itself memsets its rs485 structure to zero when RS485 is disabled but if userspace would try to make an TIOCSRS485 ioctl() call with the very same struct, it would end up failing with -EINVAL which doesn't make much sense. Resolve the problem by moving the check inside SER_RS485_ENABLED block. Fixes: 7ecc77011c6f ("serial: 8250_fintek: Return -EINVAL on invalid configuration") Cc: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/035c738-8ea5-8b17-b1d7-84a7b3aeaa51@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-05-18serial: 8250_mtk: Fix register address for XON/XOFF characterAngeloGioacchino Del Regno
commit e1bfdbc7daca171c74a577b3dd0b36d76bb0ffcc upstream. The XON1/XOFF1 character registers are at offset 0xa0 and 0xa8 respectively, so we cannot use the definition in serial_port.h. Fixes: bdbd0a7f8f03 ("serial: 8250-mtk: modify baudrate setting") Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20220427132328.228297-4-angelogioacchino.delregno@collabora.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-05-18serial: 8250_mtk: Fix UART_EFR register addressAngeloGioacchino Del Regno
commit bb0b197aadd928f52ce6f01f0ee977f0a08cf1be upstream. On MediaTek SoCs, the UART IP is 16550A compatible, but there are some specific quirks: we are declaring a register shift of 2, but this is only valid for the majority of the registers, as there are some that are out of the standard layout. Specifically, this driver is using definitions from serial_reg.h, where we have a UART_EFR register defined as 2: this results in a 0x8 offset, but there we have the FCR register instead. The right offset for the EFR register on MediaTek UART is at 0x98, so, following the decimal definition convention in serial_reg.h and accounting for the register left shift of two, add and use the correct register address for this IP, defined as decimal 38, so that the final calculation results in (0x26 << 2) = 0x98. Fixes: bdbd0a7f8f03 ("serial: 8250-mtk: modify baudrate setting") Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20220427132328.228297-2-angelogioacchino.delregno@collabora.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-05-09serial: 8250: Correct the clock for EndRun PTP/1588 PCIe deviceMaciej W. Rozycki
commit 637674fa40059cddcc3ad2212728965072f62ea3 upstream. The EndRun PTP/1588 dual serial port device is based on the Oxford Semiconductor OXPCIe952 UART device with the PCI vendor:device ID set for EndRun Technologies and is therefore driven by a fixed 62.5MHz clock input derived from the 100MHz PCI Express clock. The clock rate is divided by the oversampling rate of 16 as it is supplied to the baud rate generator, yielding the baud base of 3906250. Replace the incorrect baud base of 4000000 with the right value of 3906250 then, complementing commit 6cbe45d8ac93 ("serial: 8250: Correct the clock for OxSemi PCIe devices"). Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk> Cc: stable <stable@kernel.org> Fixes: 1bc8cde46a159 ("8250_pci: Added driver for Endrun Technologies PTP PCIe card.") Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Link: https://lore.kernel.org/r/alpine.DEB.2.21.2204181515270.9383@angie.orcam.me.uk Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-05-09serial: 8250: Also set sticky MCR bits in console restorationMaciej W. Rozycki
commit 6e6eebdf5e2455f089ccd000754a0deaeb79af82 upstream. Sticky MCR bits are lost in console restoration if console suspending has been disabled. This currently affects the AFE bit, which works in combination with RTS which we set, so we want to make sure the UART retains control of its FIFO where previously requested. Also specific drivers may need other bits in the future. Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk> Fixes: 4516d50aabed ("serial: 8250: Use canary to restart console after suspend") Cc: stable@vger.kernel.org # v4.0+ Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Link: https://lore.kernel.org/r/alpine.DEB.2.21.2204181518490.9383@angie.orcam.me.uk Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15serial: 8250: Fix race condition in RTS-after-send handlingUwe Kleine-König
[ Upstream commit dedab69fd650ea74710b2e626e63fd35584ef773 ] Set em485->active_timer = NULL isn't always enough to take out the stop timer. While there is a check that it acts in the right state (i.e. waiting for RTS-after-send to pass after sending some chars) but the following might happen: - CPU1: some chars send, shifter becomes empty, stop tx timer armed - CPU0: more chars send before RTS-after-send expired - CPU0: shifter empty irq, port lock taken - CPU1: tx timer triggers, waits for port lock - CPU0: em485->active_timer = &em485->stop_tx_timer, hrtimer_start(), releases lock() - CPU1: get lock, see em485->active_timer == &em485->stop_tx_timer, tear down RTS too early This fix bases on research done by Steffen Trumtrar. Fixes: b86f86e8e7c5 ("serial: 8250: fix potential deadlock in rs485-mode") Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Link: https://lore.kernel.org/r/20220215160236.344236-1-u.kleine-koenig@pengutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-15serial: 8250_mid: Balance reference count for PCI DMA deviceAndy Shevchenko
[ Upstream commit 67ec6dd0b257bd81b4e9fcac89b29da72f6265e5 ] The pci_get_slot() increases its reference count, the caller must decrement the reference count by calling pci_dev_put(). Fixes: 90b9aacf912a ("serial: 8250_pci: add Intel Tangier support") Fixes: f549e94effa1 ("serial: 8250_pci: add Intel Penwell ports") Reported-by: Qing Wang <wangqing@vivo.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Depends-on: d9eda9bab237 ("serial: 8250_pci: Intel MID UART support to its own driver") Link: https://lore.kernel.org/r/20220215100920.41984-1-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-02-23serial: parisc: GSC: fix build when IOSAPIC is not setRandy Dunlap
commit 6e8793674bb0d1135ca0e5c9f7e16fecbf815926 upstream. There is a build error when using a kernel .config file from 'kernel test robot' for a different build problem: hppa64-linux-ld: drivers/tty/serial/8250/8250_gsc.o: in function `.LC3': (.data.rel.ro+0x18): undefined reference to `iosapic_serial_irq' when: CONFIG_GSC=y CONFIG_SERIO_GSCPS2=y CONFIG_SERIAL_8250_GSC=y CONFIG_PCI is not set and hence PCI_LBA is not set. IOSAPIC depends on PCI_LBA, so IOSAPIC is not set/enabled. Make the use of iosapic_serial_irq() conditional to fix the build error. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reported-by: kernel test robot <lkp@intel.com> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: Helge Deller <deller@gmx.de> Cc: linux-parisc@vger.kernel.org Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: linux-serial@vger.kernel.org Cc: Jiri Slaby <jirislaby@kernel.org> Cc: Johan Hovold <johan@kernel.org> Suggested-by: Helge Deller <deller@gmx.de> Signed-off-by: Helge Deller <deller@gmx.de> Cc: stable@vger.kernel.org Signed-off-by: Helge Deller <deller@gmx.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-02-01tty: Add support for Brainboxes UC cards.Cameron Williams
commit 152d1afa834c84530828ee031cf07a00e0fc0b8c upstream. This commit adds support for the some of the Brainboxes PCI range of cards, including the UC-101, UC-235/246, UC-257, UC-268, UC-275/279, UC-302, UC-310, UC-313, UC-320/324, UC-346, UC-357, UC-368 and UC-420/431. Signed-off-by: Cameron Williams <cang1@live.co.uk> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/AM5PR0202MB2564688493F7DD9B9C610827C45E9@AM5PR0202MB2564.eurprd02.prod.outlook.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-02-01serial: 8250: of: Fix mapped region size when using reg-offset propertyRobert Hancock
commit d06b1cf28297e27127d3da54753a3a01a2fa2f28 upstream. 8250_of supports a reg-offset property which is intended to handle cases where the device registers start at an offset inside the region of memory allocated to the device. The Xilinx 16550 UART, for which this support was initially added, requires this. However, the code did not adjust the overall size of the mapped region accordingly, causing the driver to request an area of memory past the end of the device's allocation. For example, if the UART was allocated an address of 0xb0130000, size of 0x10000 and reg-offset of 0x1000 in the device tree, the region of memory reserved was b0131000-b0140fff, which caused the driver for the region starting at b0140000 to fail to probe. Fix this by subtracting reg-offset from the mapped region size. Fixes: b912b5e2cfb3 ([POWERPC] Xilinx: of_serial support for Xilinx uart 16550.) Cc: stable <stable@vger.kernel.org> Signed-off-by: Robert Hancock <robert.hancock@calian.com> Link: https://lore.kernel.org/r/20220112194214.881844-1-robert.hancock@calian.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-29serial: 8250_fintek: Fix garbled text for consoleJi-Ze Hong (Peter Hong)
commit 6c33ff728812aa18792afffaf2c9873b898e7512 upstream. Commit fab8a02b73eb ("serial: 8250_fintek: Enable high speed mode on Fintek F81866") introduced support to use high baudrate with Fintek SuperIO UARTs. It'll change clocksources when the UART probed. But when user add kernel parameter "console=ttyS0,115200 console=tty0" to make the UART as console output, the console will output garbled text after the following kernel message. [ 3.681188] Serial: 8250/16550 driver, 32 ports, IRQ sharing enabled The issue is occurs in following step: probe_setup_port() -> fintek_8250_goto_highspeed() It change clocksource from 115200 to 921600 with wrong time, it should change clocksource in set_termios() not in probed. The following 3 patches are implemented change clocksource in fintek_8250_set_termios(). Commit 58178914ae5b ("serial: 8250_fintek: UART dynamic clocksource on Fintek F81216H") Commit 195638b6d44f ("serial: 8250_fintek: UART dynamic clocksource on Fintek F81866") Commit 423d9118c624 ("serial: 8250_fintek: Add F81966 Support") Due to the high baud rate had implemented above 3 patches and the patch Commit fab8a02b73eb ("serial: 8250_fintek: Enable high speed mode on Fintek F81866") is bugged, So this patch will remove it. Fixes: fab8a02b73eb ("serial: 8250_fintek: Enable high speed mode on Fintek F81866") Signed-off-by: Ji-Ze Hong (Peter Hong) <hpeter+linux_kernel@gmail.com> Link: https://lore.kernel.org/r/20211215075835.2072-1-hpeter+linux_kernel@gmail.com Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-08serial: 8250_pci: rewrite pericom_do_set_divisor()Jay Dolan
commit bb1201d4b38ec67bd9a871cf86b0cc10f28b15b5 upstream. Have pericom_do_set_divisor() use the uartclk instead of a hard coded value to work with different speed crystals. Tested with 14.7456 and 24 MHz crystals. Have pericom_do_set_divisor() always calculate the divisor rather than call serial8250_do_set_divisor() for rates below baud_base. Do not write registers or call serial8250_do_set_divisor() if valid divisors could not be found. Fixes: 6bf4e42f1d19 ("serial: 8250: Add support for higher baud rates to Pericom chips") Cc: stable <stable@vger.kernel.org> Signed-off-by: Jay Dolan <jay.dolan@accesio.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20211122120604.3909-3-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-08serial: 8250_pci: Fix ACCES entries in pci_serial_quirks arrayJay Dolan
commit c525c5d2437f93520388920baac6d9340c65d239 upstream. Fix error in table for PCI_DEVICE_ID_ACCESIO_PCIE_ICM_4S that caused it and PCI_DEVICE_ID_ACCESIO_PCIE_ICM232_4 to be missing their fourth port. Fixes: 78d3820b9bd3 ("serial: 8250_pci: Have ACCES cards that use the four port Pericom PI7C9X7954 chip use the pci_pericom_setup()") Cc: stable <stable@vger.kernel.org> Signed-off-by: Jay Dolan <jay.dolan@accesio.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20211122120604.3909-2-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-17serial: 8250_dw: Drop wrong use of ACPI_PTR()Andy Shevchenko
[ Upstream commit ebabb77a2a115b6c5e68f7364b598310b5f61fb2 ] ACPI_PTR() is more harmful than helpful. For example, in this case if CONFIG_ACPI=n, the ID table left unused which is not what we want. Instead of adding ifdeffery here and there, drop ACPI_PTR(). Fixes: 6a7320c4669f ("serial: 8250_dw: Add ACPI 5.0 support") Reported-by: Daniel Palmer <daniel@0x0f.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20211005134516.23218-1-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-09-22serial: 8250_pci: make setup_port() parameters explicitly unsignedGreg Kroah-Hartman
[ Upstream commit 3a96e97ab4e835078e6f27b7e1c0947814df3841 ] The bar and offset parameters to setup_port() are used in pointer math, and while it would be very difficult to get them to wrap as a negative number, just be "safe" and make them unsigned so that static checkers do not trip over them unintentionally. Cc: Jiri Slaby <jirislaby@kernel.org> Reported-by: Jordy Zomer <jordy@pwning.systems> Link: https://lore.kernel.org/r/20210726130717.2052096-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-09-22serial: 8250: Define RX trigger levels for OxSemi 950 devicesMaciej W. Rozycki
[ Upstream commit d7aff291d069c4418285f3c8ee27b0ff67ce5998 ] Oxford Semiconductor 950 serial port devices have a 128-byte FIFO and in the enhanced (650) mode, which we select in `autoconfig_has_efr' with the ECB bit set in the EFR register, they support the receive interrupt trigger level selectable with FCR bits 7:6 from the set of 16, 32, 112, 120. This applies to the original OX16C950 discrete UART[1] as well as 950 cores embedded into more complex devices. For these devices we set the default to 112, which sets an excessively high level of 112 or 7/8 of the FIFO capacity, unlike with other port types where we choose at most 1/2 of their respective FIFO capacities. Additionally we don't make the trigger level configurable. Consequently frequent input overruns happen with high bit rates where hardware flow control cannot be used (e.g. terminal applications) even with otherwise highly-performant systems. Lower the default receive interrupt trigger level to 32 then, and make it configurable. Document the trigger levels along with other port types, including the set of 16, 32, 64, 112 for the transmit interrupt as well[2]. References: [1] "OX16C950 rev B High Performance UART with 128 byte FIFOs", Oxford Semiconductor, Inc., DS-0031, Sep 05, Table 10: "Receiver Trigger Levels", p. 22 [2] same, Table 9: "Transmit Interrupt Trigger Levels", p. 22 Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk> Link: https://lore.kernel.org/r/alpine.DEB.2.21.2106260608480.37803@angie.orcam.me.uk Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-08-12serial: 8250_pci: Avoid irq sharing for MSI(-X) interrupts.Mario Kleiner
commit 341abd693d10e5f337a51f140ae3e7a1ae0febf6 upstream. This attempts to fix a bug found with a serial port card which uses an MCS9922 chip, one of the 4 models for which MSI-X interrupts are currently supported. I don't possess such a card, and i'm not experienced with the serial subsystem, so this patch is based on what i think i found as a likely reason for failure, based on walking the user who actually owns the card through some diagnostic. The user who reported the problem finds the following in his dmesg output for the relevant ttyS4 and ttyS5: [ 0.580425] serial 0000:02:00.0: enabling device (0000 -> 0003) [ 0.601448] 0000:02:00.0: ttyS4 at I/O 0x3010 (irq = 125, base_baud = 115200) is a ST16650V2 [ 0.603089] serial 0000:02:00.1: enabling device (0000 -> 0003) [ 0.624119] 0000:02:00.1: ttyS5 at I/O 0x3000 (irq = 126, base_baud = 115200) is a ST16650V2 ... [ 6.323784] genirq: Flags mismatch irq 128. 00000080 (ttyS5) vs. 00000000 (xhci_hcd) [ 6.324128] genirq: Flags mismatch irq 128. 00000080 (ttyS5) vs. 00000000 (xhci_hcd) ... Output of setserial -a: /dev/ttyS4, Line 4, UART: 16650V2, Port: 0x3010, IRQ: 127 Baud_base: 115200, close_delay: 50, divisor: 0 closing_wait: 3000 Flags: spd_normal skip_test This suggests to me that the serial driver wants to register and share a MSI/MSI-X irq 128 with the xhci_hcd driver, whereas the xhci driver does not want to share the irq, as flags 0x00000080 (== IRQF_SHARED) from the serial port driver means to share the irq, and this mismatch ends in some failed irq init? With this setup, data reception works very unreliable, with dropped data, already at a transmission rate of only a 16 Bytes chunk every 1/120th of a second, ie. 1920 Bytes/sec, presumably due to rx fifo overflow due to mishandled or not used at all rx irq's? See full discussion thread with attempted diagnosis at: https://psychtoolbox.discourse.group/t/issues-with-iscan-serial-port-recording/3886 Disabling the use of MSI interrupts for the serial port pci card did fix the reliability problems. The user executed the following sequence of commands to achieve this: echo 0000:02:00.0 | sudo tee /sys/bus/pci/drivers/serial/unbind echo 0000:02:00.1 | sudo tee /sys/bus/pci/drivers/serial/unbind echo 0 | sudo tee /sys/bus/pci/devices/0000:02:00.0/msi_bus echo 0 | sudo tee /sys/bus/pci/devices/0000:02:00.1/msi_bus echo 0000:02:00.0 | sudo tee /sys/bus/pci/drivers/serial/bind echo 0000:02:00.1 | sudo tee /sys/bus/pci/drivers/serial/bind This resulted in the following log output: [ 82.179021] pci 0000:02:00.0: MSI/MSI-X disallowed for future drivers [ 87.003031] pci 0000:02:00.1: MSI/MSI-X disallowed for future drivers [ 98.537010] 0000:02:00.0: ttyS4 at I/O 0x3010 (irq = 17, base_baud = 115200) is a ST16650V2 [ 103.648124] 0000:02:00.1: ttyS5 at I/O 0x3000 (irq = 18, base_baud = 115200) is a ST16650V2 This patch attempts to fix the problem by disabling irq sharing when using MSI irq's. Note that all i know for sure is that disabling MSI irq's fixed the problem for the user, so this patch could be wrong and is untested. Please review with caution, keeping this in mind. Fixes: 8428413b1d14 ("serial: 8250_pci: Implement MSI(-X) support") Cc: Ralf Ramsauer <ralf.ramsauer@oth-regensburg.de> Cc: stable <stable@vger.kernel.org> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com> Link: https://lore.kernel.org/r/20210729043306.18528-1-mario.kleiner.de@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12serial: 8250_pci: Enumerate Elkhart Lake UARTs via dedicated driverAndy Shevchenko
commit 7f0909db761535aefafa77031062603a71557267 upstream. Elkhart Lake UARTs are PCI enumerated Synopsys DesignWare v4.0+ UART integrated with Intel iDMA 32-bit DMA controller. There is a specific driver to handle them, i.e. 8250_lpss. Hence, disable 8250_pci enumeration for these UARTs. Fixes: 1b91d97c66ef ("serial: 8250_lpss: Add ->setup() for Elkhart Lake ports") Fixes: 4f912b898dc2 ("serial: 8250_lpss: Enable HS UART on Elkhart Lake") Cc: stable <stable@vger.kernel.org> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20210713101739.36962-1-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12serial: 8250: Mask out floating 16/32-bit bus bitsMaciej W. Rozycki
commit e5227c51090e165db4b48dcaa300605bfced7014 upstream. Make sure only actual 8 bits of the IIR register are used in determining the port type in `autoconfig'. The `serial_in' port accessor returns the `unsigned int' type, meaning that with UPIO_AU, UPIO_MEM16, UPIO_MEM32, and UPIO_MEM32BE access types more than 8 bits of data are returned, of which the high order bits will often come from bus lines that are left floating in the data phase. For example with the MIPS Malta board's CBUS UART, where the registers are aligned on 8-byte boundaries and which uses 32-bit accesses, data as follows is returned: YAMON> dump -32 0xbf000900 0x40 BF000900: 1F000942 1F000942 1F000900 1F000900 ...B...B........ BF000910: 1F000901 1F000901 1F000900 1F000900 ................ BF000920: 1F000900 1F000900 1F000960 1F000960 ...........`...` BF000930: 1F000900 1F000900 1F0009FF 1F0009FF ................ YAMON> Evidently high-order 24 bits return values previously driven in the address phase (the 3 highest order address bits used with the command above are masked out in the simple virtual address mapping used here and come out at zeros on the external bus), a common scenario with bus lines left floating, due to bus capacitance. Consequently when the value of IIR, mapped at 0x1f000910, is retrieved in `autoconfig', it comes out at 0x1f0009c1 and when it is right-shifted by 6 and then assigned to 8-bit `scratch' variable, the value calculated is 0x27, not one of 0, 1, 2, 3 expected in port type determination. Fix the issue then, by assigning the value returned from `serial_in' to `scratch' first, which masks out 24 high-order bits retrieved, and only then right-shift the resulting 8-bit data quantity, producing the value of 3 in this case, as expected. Fix the same issue in `serial_dl_read'. The problem first appeared with Linux 2.6.9-rc3 which predates our repo history, but the origin could be identified with the old MIPS/Linux repo also at: <git://git.kernel.org/pub/scm/linux/kernel/git/ralf/linux.git> as commit e0d2356c0777 ("Merge with Linux 2.6.9-rc3."), where code in `serial_in' was updated with this case: + case UPIO_MEM32: + return readl(up->port.membase + offset); + which made it produce results outside the unsigned 8-bit range for the first time, though obviously it is system dependent what actual values appear in the high order bits retrieved and it may well have been zeros in the relevant positions with the system the change originally was intended for. It is at that point that code in `autoconf' should have been updated accordingly, but clearly it was overlooked. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable@vger.kernel.org # v2.6.12+ Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk> Link: https://lore.kernel.org/r/alpine.DEB.2.21.2106260516220.37803@angie.orcam.me.uk Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>