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* serial: 8250: Store to lsr_save_flags after lsr readIlpo Järvinen2022-06-101-0/+2
| | | | | | | | | | | | | | | | | | | | | | 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>
* Merge tag 'tty-5.19-rc1' of ↵Linus Torvalds2022-06-0314-303/+784
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty Pull tty and serial driver updates from Greg KH: "Here is the big set of tty and serial driver updates for 5.19-rc1. Lots of tiny cleanups in here, the major stuff is: - termbit cleanups and unification by Ilpo. A much needed change that goes a long way to making things simpler for all of the different arches - tty documentation cleanups and movements to their own place in the documentation tree - old tty driver cleanups and fixes from Jiri to bring some existing drivers into the modern world - RS485 cleanups and unifications to make it easier for individual drivers to support this mode instead of having to duplicate logic in each driver - Lots of 8250 driver updates and additions - new device id additions - n_gsm continued fixes and cleanups - other minor serial driver updates and cleanups All of these have been in linux-next for weeks with no reported issues" * tag 'tty-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (166 commits) tty: Rework receive flow control char logic pcmcia: synclink_cs: Don't allow CS5-6 serial: stm32-usart: Correct CSIZE, bits, and parity serial: st-asc: Sanitize CSIZE and correct PARENB for CS7 serial: sifive: Sanitize CSIZE and c_iflag serial: sh-sci: Don't allow CS5-6 serial: txx9: Don't allow CS5-6 serial: rda-uart: Don't allow CS5-6 serial: digicolor-usart: Don't allow CS5-6 serial: uartlite: Fix BRKINT clearing serial: cpm_uart: Fix build error without CONFIG_SERIAL_CPM_CONSOLE serial: core: Do stop_rx in suspend path for console if console_suspend is disabled tty: serial: qcom-geni-serial: Remove uart frequency table. Instead, find suitable frequency with call to clk_round_rate. dt-bindings: serial: renesas,em-uart: Add RZ/V2M clock to access the registers serial: 8250_fintek: Check SER_RS485_RTS_* only with RS485 Revert "serial: 8250_mtk: Make sure to select the right FEATURE_SEL" serial: msm_serial: disable interrupts in __msm_console_write() serial: meson: acquire port->lock in startup() serial: 8250_dw: Use dev_err_probe() serial: 8250_dw: Use devm_add_action_or_reset() ...
| * serial: 8250_fintek: Check SER_RS485_RTS_* only with RS485Ilpo Järvinen2022-05-191-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * Revert "serial: 8250_mtk: Make sure to select the right FEATURE_SEL"AngeloGioacchino Del Regno2022-05-191-7/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It was found that some MediaTek SoCs are incompatible with this change. Also, this register was mistakenly understood as it was related to the 16550A register layout selection but, at least on some IPs, if not all, it's related to something else unknown. This reverts commit 6f81fdded0d024c7d4084d434764f30bca1cd6b1. Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> Fixes: 6f81fdded0d0 ("serial: 8250_mtk: Make sure to select the right FEATURE_SEL") Reported-by: "kernelci.org bot" <bot@kernelci.org> Link: https://lore.kernel.org/r/20220510122620.150342-1-angelogioacchino.delregno@collabora.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * serial: 8250_dw: Use dev_err_probe()Andy Shevchenko2022-05-191-17/+11
| | | | | | | | | | | | | | | | Simplify the error path in ->probe() a bit by using dev_err_probe(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20220509172129.37770-2-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * serial: 8250_dw: Use devm_add_action_or_reset()Andy Shevchenko2022-05-191-32/+31
| | | | | | | | | | | | | | | | | | Slightly simplify ->probe() and drop a few goto labels by using devm_add_action_or_reset() for clock and reset cleanup. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20220509172129.37770-1-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * serial: 8250_dw: Update the list of OF headers used by driverAndy Shevchenko2022-05-191-2/+1
| | | | | | | | | | | | | | | | | | | | The of_irq.h and of_platform.h are not used by the driver. On the other hand, the mod_devicetable.h missed. Drop the former two and add the latter one. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20220509161911.37164-1-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * tty: remove CMSPAR ifdefsIlpo Järvinen2022-05-191-2/+0
| | | | | | | | | | | | | | | | | | | | CMSPAR is defined by all architectures since commit 6bf08cb246b5 ("[PATCH] Add CMSPAR to termbits.h for powerpc and alpha"). Reviewed-by: Johan Hovold <johan@kernel.org> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20220513082906.11096-2-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * Merge 5.18-rc7 into usb-nextGreg Kroah-Hartman2022-05-161-9/+20
| |\ | | | | | | | | | | | | | | | We need the tty fixes in here as well, as we need to revert one of them :( Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | serial: 8250: Add proper clock handling for OxSemi PCIe devicesMaciej W. Rozycki2022-05-051-68/+271
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Oxford Semiconductor PCIe (Tornado) 950 serial port devices are driven by a fixed 62.5MHz clock input derived from the 100MHz PCI Express clock. We currently drive the device using its default oversampling rate of 16 and the clock prescaler disabled, consequently yielding the baud base of 3906250. This base is inadequate for some of the high-speed baud rates such as 460800bps, for which the closest rate possible can be obtained by dividing the baud base by 8, yielding the baud rate of 488281.25bps, which is off by 5.9638%. This is enough for data communication to break with the remote end talking actual 460800bps, where missed stop bits have been observed. We can do better however, by taking advantage of a reduced oversampling rate, which can be set to any integer value from 4 to 16 inclusive by programming the TCR register, and by using the clock prescaler, which can be set to any value from 1 to 63.875 in increments of 0.125 in the CPR/CPR2 register pair. The prescaler has to be explicitly enabled though by setting bit 7 in the MCR or otherwise it is bypassed (in the enhanced mode that we enable) as if the value of 1 was used. Make use of these features then as follows: - Set the baud base to 15625000, reflecting the minimum oversampling rate of 4 with the clock prescaler and divisor both set to 1. - Override the `set_mctrl' and set the MCR shadow there so as to have MCR[7] always set and have the 8250 core propagate these settings. - Override the `get_divisor' handler and determine a good combination of parameters by using a lookup table with predetermined value pairs of the oversampling rate and the clock prescaler and finding a pair that divides the input clock such that the quotient, when rounded to the nearest integer, deviates the least from the exact result. Calculate the clock divisor accordingly. Scale the resulting oversampling rate (only by powers of two) if possible so as to maximise it, reducing the divisor accordingly, and avoid a divisor overflow for very low baud rates by scaling the oversampling rate and/or the prescaler even if that causes some accuracy loss. Also handle the historic spd_cust feature so as to allow one to set all the three parameters manually to arbitrary values, by keeping the low 16 bits for the divisor and then putting TCR in bits 19:16 and CPR/CPR2 in bits 28:20, sanitising the bit pattern supplied such as to clamp CPR/CPR2 values between 0.000 and 0.875 inclusive to 33.875. This preserves compatibility with any existing setups, that is where requesting a custom divisor that only has any bits set among the low 16 the oversampling rate of 16 and the clock prescaler of 33.875 will be used as with the original 8250. Finally abuse the `frac' argument to store the determined bit patterns for the TCR, CPR and CPR2 registers. - Override the `set_divisor' handler so as to set the TCR, CPR and CPR2 registers from the `frac' value supplied. Set the divisor as usual. With the baud base set to 15625000 and the unsigned 16-bit UART_DIV_MAX limitation imposed by `serial8250_get_baud_rate' standard baud rates below 300bps become unavailable in the regular way, e.g. the rate of 200bps requires the baud base to be divided by 78125 and that is beyond the unsigned 16-bit range. The historic spd_cust feature can still be used to obtain such rates if so required. See Documentation/tty/device_drivers/oxsemi-tornado.rst for more details. Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk> Link: https://lore.kernel.org/r/alpine.DEB.2.21.2204181519450.9383@angie.orcam.me.uk Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | serial: 8250: Export ICR access helpers for internal useMaciej W. Rozycki2022-05-052-21/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make ICR access helpers available outside 8250_port.c, however retain them as ordinary static functions so as not to regress code generation. This is because `serial_icr_write' is currently automatically inlined by GCC, however `serial_icr_read' is not. Making them both static inline would grow code produced, e.g.: $ i386-linux-gnu-size --format=gnu 8250_port-{old,new}.o text data bss total filename 15065 3378 0 18443 8250_port-old.o 15289 3378 0 18667 8250_port-new.o and: $ riscv64-linux-gnu-size --format=gnu 8250_port-{old,new}.o text data bss total filename 16980 5306 0 22286 8250_port-old.o 17124 5306 0 22430 8250_port-new.o while making them external would needlessly add a new module interface and lose the benefit from `serial_icr_write' getting inlined outside 8250_port.o. Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Link: https://lore.kernel.org/r/alpine.DEB.2.21.2204181517500.9383@angie.orcam.me.uk Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | serial: 8250: Fold EndRun device support into OxSemi Tornado codeMaciej W. Rozycki2022-05-051-51/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 uses the same sequence to determine the number of ports available. Despite that we have duplicate code specific to the EndRun device. Remove redundant code then and factor out OxSemi Tornado device detection. Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Link: https://lore.kernel.org/r/alpine.DEB.2.21.2204181516220.9383@angie.orcam.me.uk Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | serial: 8250: pxa: Remove unneeded <linux/pm_runtime.h>Geert Uytterhoeven2022-05-051-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The 8250 PXA driver never used Runtime PM, so there was never a need to include <linux/pm_runtime.h>. Fixes: ab28f51c77cd4618 ("serial: rewrite pxa2xx-uart to use 8250_core") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/9fd96fba9bbbbdeb16af0dc07ae9dee21c8e297c.1651494971.git.geert+renesas@glider.be Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | serial: 8250: core: Remove unneeded <linux/pm_runtime.h>Geert Uytterhoeven2022-05-051-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The last calls into Runtime PM were moved to 8250_port.c a long time ago. Fixes: b6830f6df8914faa ("serial: 8250: Split base port operations from universal driver") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/2545eaa7fc552013a5d04c4df027255204e64834.1651494971.git.geert+renesas@glider.be Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | serial: 8250: dw: Fix NULL pointer dereferenceHeikki Krogerus2022-05-051-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | dw8250_platform_data is only used on DT platforms for now. Fixes: 4a218b277fdb ("serial: 8250: dw: Create a generic platform data structure") Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20220502115621.77985-1-heikki.krogerus@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | Merge 5.18-rc5 into tty-nextGreg Kroah-Hartman2022-05-022-7/+7
| |\ \ | | | | | | | | | | | | | | | | | | | | We need the tty/serial fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | serial: 8250_dwlib: Implement SW half duplex supportIlpo Järvinen2022-04-261-2/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch enables support for SW half-duplex mode using em485. Cc: Eric Tremblay <etremblay@distech-controls.com> Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Tested-by: Vicente Bergas <vicencb@gmail.com> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20220426122448.38997-3-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | serial: 8250_dwlib: RS485 HW half & full duplex supportIlpo Järvinen2022-04-262-0/+85
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The Synopsys DesignWare UART can be configured to have HW support for the RS485 protocol from IP version 4.0 onward. Add support for hardware-controlled half duplex and full duplex modes. HW will take care of managing DE and RE, the driver just gives it permission to use either by setting both to 1. To ask for full duplex mode, userspace sets SER_RS485_RX_DURING_TX flag and HW will take care of the rest. Set delay_rts_before_send and delay_rts_after_send to zero for now. The granularity of that ABI is too coarse to be useful. Co-developed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Co-developed-by: Raymond Tan <raymond.tan@intel.com> Signed-off-by: Raymond Tan <raymond.tan@intel.com> Co-developed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20220426122448.38997-2-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | serial: 8250: Handle UART without interrupt on TEMTIlpo Järvinen2022-04-261-9/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add UART_CAP_NOTEMT for UARTs that lack interrupt on TEMT but want to use em485. Em485 framework needs to ensure not only FIFO is empty but also that tx shift register is empty. This approach uses Uwe Kleine-König's suggestion on simply using/incrementing stop_tx timer rather than adding another timer. When UART_CAP_NOTEMT is set and THRE is present w/o TEMT, stop tx timer is reused to wait for the emptying of the shift register. This change does not add the UART_CAP_NOTEMT define as it already exist but is currently no-op. See 7a107b2c6b81 (Revert "serial: 8250: Handle UART without interrupt on TEMT using em485") for further details. Vicente Bergas reported that RTS is deasserted roughly one bit too early losing stop bit tx. To address this problem, stop_delay now accounts for one extra bit using rough formula /7 (assumes worst-case of 2+5 bits). I suspect this glitch had to do with when THRE is getting asserted. If FIFO is emptied already during the tx of the stop bit, perhaps it leads to HW asserting THRE early for the normal frame time formula to work accurately. Suggested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Cc: Eric Tremblay <etremblay@distech-controls.com> Tested-by: Vicente Bergas <vicencb@gmail.com> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20220425143410.12703-4-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | serial: 8250: use THRE & __stop_tx also with DMAIlpo Järvinen2022-04-262-5/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 8250 DMA tx complete path lacks calls to normal 8250 stop handling. It does not use THRE to detect true completion of the tx and also doesn't call __stop_tx. This leads to problems with em485 that needs to handle RTS timing. Instead of handling tx stop internally within 8250 dma code, enable THRE when tx'able data runs out and tweak serial8250_handle_irq to call only __stop_tx when uart is using DMA. It also seems bit early to call serial8250_rpm_put_tx from there while tx is still underway(?). Tested-by: Vicente Bergas <vicencb@gmail.com> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20220425143410.12703-3-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | serial: 8250: dw: Improve RZN1 supportPhil Edworthy2022-04-261-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Renesas RZ/N1 SoC features a slightly modified DW UART. On this SoC, the CPR register value is known but not synthetized in hardware. We hence need to provide a CPR value in the platform data. This version of the controller also relies on acting as flow controller when using DMA, so we need to provide the "is dma flow controller" quirk. Co-developed-by: Miquel Raynal <miquel.raynal@bootlin.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Link: https://lore.kernel.org/r/20220422180615.9098-10-miquel.raynal@bootlin.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | serial: 8250: dw: Add support for DMA flow controlling devicesPhil Edworthy2022-04-261-0/+64
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | DW based controllers like the one on Renesas RZ/N1 must be programmed as flow controllers when using DMA. * Table 11.45 of the system manual, "Flow Control Combinations", states that using UART with DMA requires setting the DMA in the peripheral flow controller mode regardless of the direction. * Chapter 11.6.1.3 of the system manual, "Basic Interface Definitions", explains that the burst size in the above case must be configured in the peripheral's register DEST/SRC_BURST_SIZE. Experiments shown that upon Rx timeout, the DMA transaction needed to be manually cleared as well. Co-developed-by: Miquel Raynal <miquel.raynal@bootlin.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Link: https://lore.kernel.org/r/20220422180615.9098-9-miquel.raynal@bootlin.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | serial: 8250: dw: Move the IO accessors to 8250_dwlib.hMiquel Raynal2022-04-262-16/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | These accessors should be used instead of the regular readl/writel() helpers. In order to use them also from 8250_dw.c in this directory, move the helpers to 8250_dwlib.h There is no functional change. There is no need for declaring `struct uart_port` or even UPIO_MEM32BE which both are already included in the 8250_dwlib.h header by 8250.h. Suggested-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Link: https://lore.kernel.org/r/20220422180615.9098-8-miquel.raynal@bootlin.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | serial: 8250: dw: Introduce an rx_timeout variable in the IRQ pathMiquel Raynal2022-04-261-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In a next change we are going to need the same Rx timeout condition as we already have in the IRQ handling code. Let's just create a boolean to clarify what this operation does before reusing it. There is no functional change. Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Link: https://lore.kernel.org/r/20220422180615.9098-7-miquel.raynal@bootlin.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | serial: 8250: dma: Allow driver operations before starting DMA transfersMiquel Raynal2022-04-262-0/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | One situation where this could be used is when configuring the UART controller to be the DMA flow controller. This is a typical case where the driver might need to program a few more registers before starting a DMA transfer. Provide the necessary infrastructure to support this case. Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Link: https://lore.kernel.org/r/20220422180615.9098-6-miquel.raynal@bootlin.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | serial: 8250: dw: Allow to use a fallback CPR value if not synthesizedMiquel Raynal2022-04-262-3/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | DW UART controllers can be synthesized without the CPR register. In this case, allow to the platform information to provide a CPR value. Co-developed-by: Phil Edworthy <phil.edworthy@renesas.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Link: https://lore.kernel.org/r/20220422180615.9098-5-miquel.raynal@bootlin.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | serial: 8250: dw: Move the USR register to pdataMiquel Raynal2022-04-262-4/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This offset is a good candidate to pdata's because it changes depending on the vendor implementation. Let's move the usr_reg entry from regular to pdata. This way we can drop initializing it at run time. Let's also use a define for it instead of defining only the default value. Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Link: https://lore.kernel.org/r/20220422180615.9098-4-miquel.raynal@bootlin.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | serial: 8250: dw: Create a generic platform data structureEmil Renner Berthing2022-04-262-8/+39
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use device tree match data rather than multiple calls to of_device_is_compatible() by introducing a platform data structure and adding a quirks mask. Provide a stub to the compatibles without quirks to simplify the handling of the upcoming changes. Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Emil Renner Berthing <kernel@esmil.dk> [<miquel.raynal@bootlin.com: Minor changes + creation of a real pdata structure] Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Link: https://lore.kernel.org/r/20220422180615.9098-3-miquel.raynal@bootlin.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | serial: 8250: dw: Move definitions to the shared headerPhil Edworthy2022-04-262-21/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Move the per-device structure and a helper out of the main .c file, into a shared header as they will both be reused from another .c file. There is no functional change. Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com> [miquel.raynal@bootlin.com: Extracted from a bigger change] Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Link: https://lore.kernel.org/r/20220422180615.9098-2-miquel.raynal@bootlin.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | serial/8250: Use fifo in 8250 console driverWander Lairson Costa2022-04-221-6/+65
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Note: I am using a small test app + driver located at [0] for the problem description. serco is a driver whose write function dispatches to the serial controller. sertest is a user-mode app that writes n bytes to the serial console using the serco driver. While investigating a bug in the RHEL kernel, I noticed that the serial console throughput is way below the configured speed of 115200 bps in a HP Proliant DL380 Gen9. I was expecting something above 10KB/s, but I got 2.5KB/s. $ time ./sertest -n 2500 /tmp/serco real 0m0.997s user 0m0.000s sys 0m0.997s With the help of the function tracer, I then noticed the serial controller was taking around 410us seconds to dispatch one single byte: $ trace-cmd record -p function_graph -g serial8250_console_write \ ./sertest -n 1 /tmp/serco $ trace-cmd report | serial8250_console_write() { 0.384 us | _raw_spin_lock_irqsave(); 1.836 us | io_serial_in(); 1.667 us | io_serial_out(); | uart_console_write() { | serial8250_console_putchar() { | wait_for_xmitr() { 1.870 us | io_serial_in(); 2.238 us | } 1.737 us | io_serial_out(); 4.318 us | } 4.675 us | } | wait_for_xmitr() { 1.635 us | io_serial_in(); | __const_udelay() { 1.125 us | delay_tsc(); 1.429 us | } ... ... ... 1.683 us | io_serial_in(); | __const_udelay() { 1.248 us | delay_tsc(); 1.486 us | } 1.671 us | io_serial_in(); 411.342 us | } In another machine, I measured a throughput of 11.5KB/s, with the serial controller taking between 80-90us to send each byte. That matches the expected throughput for a configuration of 115200 bps. This patch changes the serial8250_console_write to use the 16550 fifo if available. In my benchmarks I got around 25% improvement in the slow machine, and no performance penalty in the fast machine. Signed-off-by: Wander Lairson Costa <wander@redhat.com> Link: https://lore.kernel.org/r/20220411174841.34936-2-wander@redhat.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | Revert "serial: 8250: Handle UART without interrupt on TEMT using em485"Ilpo Järvinen2022-04-201-74/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This partially reverts commit f6f586102add. The code added by that commit containted math overflow for 32-bit archs. In addition, the approach used in it is unnecessarily complicated requiring a dedicated timer just for notemt. A simpler approach for providing UART_CAP_NOTEMT already exists (patches 1-2): https://lore.kernel.org/linux-serial/20220411083321.9131-3-ilpo.jarvinen@linux.intel.com/T/#u Thus, simply revert the UART_CAP_NOTEMT change for now. There were two driver changes within the patch series adding UART_CAP_NOTEMT taking advantage of the newly added flag. This does not revert the driver changes and therefore also UART_CAP_NOTEMT define has to remain. UART_CAP_NOTEMT remains no-op until support is again added. Fixes: f6f586102add ("serial: 8250: Handle UART without interrupt on TEMT using em485") Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/5f874142-fb1f-bff7-f33-fac823e65e2e@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | serial: 8250: add compatible for fsl,16550-FIFO64Eric Tremblay2022-04-151-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Eric Tremblay <etremblay@distech-controls.com> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Link: https://lore.kernel.org/r/20220330104642.229507-4-u.kleine-koenig@pengutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | serial: 8250: Add UART_CAP_NOTEMT on PORT_16550A_FSL64Eric Tremblay2022-04-151-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The Freescale variant of the 16550A doesn't have an interrupt on TEMT available when using the FIFO mode. Signed-off-by: Eric Tremblay <etremblay@distech-controls.com> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Link: https://lore.kernel.org/r/20220330104642.229507-3-u.kleine-koenig@pengutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | serial: 8250: Handle UART without interrupt on TEMT using em485Eric Tremblay2022-04-152-2/+75
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Introduce the UART_CAP_NOTEMT capability. The capability indicates that the UART doesn't have an interrupt available on TEMT. In the case where the device does not support it, we calculate the maximum time it could take for the transmitter to empty the shift register. When we get in the situation where we get the THRE interrupt, we check if the TEMT bit is set. If it's not, we start the a timer and recall __stop_tx() after the delay. The transmit sequence is a bit modified when the capability is set. The new timer is used between the last interrupt(THRE) and a potential stop_tx timer. Signed-off-by: Giulio Benetti <giulio.benetti@micronovasrl.com> [moved to use added UART_CAP_TEMT] Signed-off-by: Heiko Stuebner <heiko.stuebner@theobroma-systems.com> [moved to use added UART_CAP_NOTEMT, improve timeout] Signed-off-by: Eric Tremblay <etremblay@distech-controls.com> [rebased to v5.17, making use of tty_get_frame_size] Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Link: https://lore.kernel.org/r/20220330104642.229507-2-u.kleine-koenig@pengutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | serial: 8250_aspeed_vuart: Fix potential NULL dereference in aspeed_vuart_probeMiaoqian Lin2022-04-151-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | platform_get_resource() may fail and return NULL, so we should better check it's return value to avoid a NULL pointer dereference. Fixes: 54da3e381c2b ("serial: 8250_aspeed_vuart: use UPF_IOREMAP to set up register mapping") Signed-off-by: Miaoqian Lin <linmq006@gmail.com> Link: https://lore.kernel.org/r/20220404143842.16960-1-linmq006@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | serial: 8250: Report which option to enable for blacklisted PCI devicesMaciej W. Rozycki2022-04-151-27/+40
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Provide information in the kernel log as to what configuration option to enable for PCI UART devices that have been blacklisted in the generic PCI 8250 UART driver and which have a dedicated driver available to handle that has been disabled. The rationale is there is no easy way for the user to map a specific PCI vendor:device pair to an individual dedicated driver while the generic driver has this information readily available and it will likely be confusing that the generic driver does not register such a port. This is unlike usual drivers, such as drivers/net/ethernet/3com/3c59x.c which handles all the hardware family members regardless of differences between them, and following an existing example where a serio driver provides suggestions as to the correct configuration options to use: psmouse serio1: synaptics: The touchpad can support a better bus than the too old PS/2 protocol. Make sure MOUSE_PS2_SYNAPTICS_SMBUS and RMI4_SMB are enabled to get a better touchpad experience. A message is then printed like: serial 0000:04:00.3: ignoring port, enable SERIAL_8250_PERICOM to handle when an affected device is encountered and the generic driver rejects it. Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk> Link: https://lore.kernel.org/r/alpine.DEB.2.21.2203310054120.44113@angie.orcam.me.uk Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | serial: 8250: Make SERIAL_8250_EM available for arm64 systemsPhil Edworthy2022-04-151-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is needed for the Renesas RZ/V2M (r9a09g011) SoC. Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com> Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20220330154024.112270-6-phil.edworthy@renesas.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | | | Merge tag 'arm-multiplatform-5.19-1' of ↵Linus Torvalds2022-05-261-0/+1
|\ \ \ \ | |_|_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc Pull ARMv4T/v5 multiplatform support from Arnd Bergmann: "This series has been 12 years in the making, it mostly finishes the work that was started with the founding of Linaro to clean up platform support in the kernel. The largest change here is a cleanup of the omap1 platform, which is the final ARM machine type to get converted to the common-clk subsystem. All the omap1 specific drivers are now made independent of the mach/*.h headers to allow the platform to be part of a generic ARMv4/v5 multiplatform kernel. The last bit that enables this support is still missing here while we wait for some last dependencies to make it into the mainline kernel through other subsystems. The s3c24xx, ixp4xx, iop32x, ep93xx and dove platforms were all almost at the point of allowing multiplatform kernels, this work gets completed here along with a few additional cleanup. At the same time, the s3c24xx and s3c64xx are now deprecated and expected to get removed in the future. The PXA and OMAP1 bits are in a separate branch because of dependencies. Once both branches are merged, only the three Intel StrongARM platforms (RiscPC, Footbridge/NetWinder and StrongARM1100) need separate kernels, and there are no plans to include these" * tag 'arm-multiplatform-5.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (61 commits) ARM: ixp4xx: Consolidate Kconfig fixing issue ARM: versatile: Add missing of_node_put in dcscb_init ARM: config: Refresh IXP4xx config after multiplatform ARM: omap1: add back omap_set_dma_priority() stub ARM: omap: fix missing declaration warnings ARM: omap: fix address space warnings from sparse ARM: spear: remove include/mach/ subdirectory ARM: davinci: remove include/mach/ subdirectory ARM: omap2: remove include/mach/ subdirectory integrator: remove empty ap_init_early() ARM: s3c: fix include path MAINTAINERS: omap1: Add Janusz as an additional maintainer ARM: omap1: htc_herald: fix typos in comments ARM: OMAP1: fix typos in comments ARM: OMAP1: clock: Remove noop code ARM: OMAP1: clock: Remove unused code ARM: OMAP1: clock: Fix UART rate reporting algorithm ARM: OMAP1: clock: Fix early UART rate issues ARM: OMAP1: Prepare for conversion of OMAP1 clocks to CCF ARM: omap1: fix build with no SoC selected ...
| * | | serial: 8250/omap1: include linux/soc/ti/omap1-soc.hArnd Bergmann2022-04-211-0/+1
| |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | As a preparation for cleaning up the omap1 headers, start including linux/soc/ti/omap1-soc.h directly so we can keep calling cpu_is_omap1510(). Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
* | | serial: 8250_mtk: Fix register address for XON/XOFF characterAngeloGioacchino Del Regno2022-05-051-2/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | | serial: 8250_mtk: Make sure to select the right FEATURE_SELAngeloGioacchino Del Regno2022-05-051-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Set the FEATURE_SEL at probe time to make sure that BIT(0) is enabled: this guarantees that when the port is configured as AP UART, the right register layout is interpreted by the UART IP. Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20220427132328.228297-3-angelogioacchino.delregno@collabora.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | | serial: 8250_mtk: Fix UART_EFR register addressAngeloGioacchino Del Regno2022-05-051-7/+8
| |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | serial: 8250: Correct the clock for EndRun PTP/1588 PCIe deviceMaciej W. Rozycki2022-04-221-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | serial: 8250: Also set sticky MCR bits in console restorationMaciej W. Rozycki2022-04-221-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | serial: 8250: Fix runtime PM for start_tx() for empty bufferTony Lindgren2022-04-151-2/+2
|/ | | | | | | | | | | | | | | | Commit 932d596378b0 ("serial: 8250: Return early in .start_tx() if there are no chars to send") caused a regression where the drivers implementing runtime PM stopped idling. This is because serial8250_rpm_put_tx() is now unbalanced on early return, it normally gets called at __stop_tx(). Fixes: 932d596378b0 ("serial: 8250: Return early in .start_tx() if there are no chars to send") Cc: Steffen Trumtrar <s.trumtrar@pengutronix.de> Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Reviewed-by: Johan Hovold <johan@kernel.org> Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Tony Lindgren <tony@atomide.com> Link: https://lore.kernel.org/r/20220411111657.16744-1-tony@atomide.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* serial: 8250: fix XOFF/XON sending when DMA is usedIlpo Järvinen2022-03-182-4/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | When 8250 UART is using DMA, x_char (XON/XOFF) is never sent to the wire. After this change, x_char is injected correctly. Create uart_xchar_out() helper for sending the x_char out and accounting related to it. It seems that almost every driver does these same steps with x_char. Except for 8250, however, almost all currently lack .serial_out so they cannot immediately take advantage of this new helper. The downside of this patch is that it might reintroduce the problems some devices faced with mixed DMA/non-DMA transfer which caused revert f967fc8f165f (Revert "serial: 8250_dma: don't bother DMA with small transfers"). However, the impact should be limited to cases with XON/XOFF (that didn't work with DMA capable devices to begin with so this problem is not very likely to cause a major issue, if any at all). Fixes: 9ee4b83e51f74 ("serial: 8250: Add support for dmaengine") Reported-by: Gilles Buloz <gilles.buloz@kontron.com> Tested-by: Gilles Buloz <gilles.buloz@kontron.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20220314091432.4288-2-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* serial: 8250_tegra: mark acpi_device_id as unused with !ACPIKrzysztof Kozlowski2022-03-181-1/+1
| | | | | | | | | | | | The driver's acpi_device_id table is referenced via ACPI_PTR() so it will be unused for !CONFIG_ACPI builds: drivers/tty/serial/8250/8250_tegra.c:178:36: warning: ‘tegra_uart_acpi_match’ defined but not used [-Wunused-const-variable=] Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com> Link: https://lore.kernel.org/r/20220308074157.113568-1-krzysztof.kozlowski@canonical.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* serial: 8250_mtk: make two read-only arrays static constColin Ian King2022-03-181-2/+2
| | | | | | | | | | Don't populate the read-only arrays fraction_L_mapping and fraction_M_mapping on the stack but instead make them static const. Also makes the object code a little smaller. Signed-off-by: Colin Ian King <colin.i.king@gmail.com> Link: https://lore.kernel.org/r/20220307230055.168241-1-colin.i.king@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* serial: make uart_console_write->putchar()'s character an unsigned charJiri Slaby2022-03-033-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, uart_console_write->putchar's second parameter (the character) is of type int. It makes little sense, provided uart_console_write() accepts the input string as "const char *s" and passes its content -- the characters -- to putchar(). So switch the character's type to unsigned char. We don't use char as that is signed on some platforms. That would cause troubles for drivers which (implicitly) cast the char to u16 when writing to the device. Sign extension would happen in that case and the value written would be completely different to the provided char. DZ is an example of such a driver -- on MIPS, it uses u16 for dz_out in dz_console_putchar(). Note we do the char -> uchar conversion implicitly in uart_console_write(). Provided we do not change size of the data type, sign extension does not happen there, so the problem is void. This makes the types consistent and unified with the rest of the uart layer, which uses unsigned char in most places already. One exception is xmit_buf, but that is going to be converted later. Cc: Paul Cercueil <paul@crapouillou.net> Cc: Tobias Klauser <tklauser@distanz.ch> Cc: Russell King <linux@armlinux.org.uk> Cc: Vineet Gupta <vgupta@kernel.org> Cc: Nicolas Ferre <nicolas.ferre@microchip.com> Cc: Alexandre Belloni <alexandre.belloni@bootlin.com> Cc: Ludovic Desroches <ludovic.desroches@microchip.com> Cc: Florian Fainelli <f.fainelli@gmail.com> Cc: bcm-kernel-feedback-list@broadcom.com Cc: Alexander Shiyan <shc_work@mail.ru> Cc: Baruch Siach <baruch@tkos.co.il> Cc: "Maciej W. Rozycki" <macro@orcam.me.uk> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Shawn Guo <shawnguo@kernel.org> Cc: Sascha Hauer <s.hauer@pengutronix.de> Cc: Pengutronix Kernel Team <kernel@pengutronix.de> Cc: Fabio Estevam <festevam@gmail.com> Cc: NXP Linux Team <linux-imx@nxp.com> Cc: Karol Gugala <kgugala@antmicro.com> Cc: Mateusz Holenko <mholenko@antmicro.com> Cc: Vladimir Zapolskiy <vz@mleia.com> Cc: Neil Armstrong <narmstrong@baylibre.com> Cc: Kevin Hilman <khilman@baylibre.com> Cc: Jerome Brunet <jbrunet@baylibre.com> Cc: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Cc: Taichi Sugaya <sugaya.taichi@socionext.com> Cc: Takao Orito <orito.takao@socionext.com> Cc: Liviu Dudau <liviu.dudau@arm.com> Cc: Sudeep Holla <sudeep.holla@arm.com> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: "Andreas Färber" <afaerber@suse.de> Cc: Manivannan Sadhasivam <mani@kernel.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Andy Gross <agross@kernel.org> Cc: Bjorn Andersson <bjorn.andersson@linaro.org> Cc: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com> Cc: Orson Zhai <orsonzhai@gmail.com> Cc: Baolin Wang <baolin.wang7@gmail.com> Cc: Chunyan Zhang <zhang.lyra@gmail.com> Cc: Patrice Chotard <patrice.chotard@foss.st.com> Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com> Cc: Alexandre Torgue <alexandre.torgue@foss.st.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Peter Korsgaard <peter@korsgaard.com> Cc: Michal Simek <michal.simek@xilinx.com> Acked-by: Richard Genoud <richard.genoud@gmail.com> [atmel_serial] Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Acked-by: Paul Cercueil <paul@crapouillou.net> Acked-by: Neil Armstrong <narmstrong@baylibre.com> # meson_serial Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20220303080831.21783-1-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* tty: serial: make use of UART_LCR_WLEN() + tty_get_char_size()Jiri Slaby2022-02-282-30/+2
| | | | | | | | | | | | | | Having a generic UART_LCR_WLEN() macro and the tty_get_char_size() helper, we can remove all those repeated switch-cases in drivers. Cc: Laxman Dewangan <ldewangan@nvidia.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Jonathan Hunter <jonathanh@nvidia.com> Cc: linux-tegra@vger.kernel.org Reviewed-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20220224095558.30929-2-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
generated by cgit v1.2.3-71-gd317 (git 2.46.0) at 2026-01-02 19:57:26 +0000