summaryrefslogtreecommitdiffstats
path: root/drivers/tty/serial/fsl_lpuart.c
Commit message (Collapse)AuthorAgeFilesLines
...
| * tty: serial: fsl_lpuart: specify transmit FIFO sizeStefan Agner2015-03-261-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Specify transmit FIFO size which might be different depending on LPUART instance. This makes sure uart_wait_until_sent in serial core getting called, which in turn waits and checks if the FIFO is really empty on shutdown by using the tx_empty callback. Without the call of this callback, the last several characters might not yet be transmitted when closing the serial port. This can be reproduced by simply using echo and redirect the output to a ttyLP device. Signed-off-by: Stefan Agner <stefan@agner.ch> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | tty: constify of_device_id arrayFabian Frederick2015-03-261-1/+1
|/ | | | | | | | | | | of_device_id is always used as const. (See driver.of_match_table and open firmware functions) Signed-off-by: Fabian Frederick <fabf@skynet.be> Acked-by: Peter Korsgaard <peter@korsgaard.com> Acked-by: Timur Tabi <timur@tabi.org> Acked-by: Patrice Chotard <patrice.chotard@st.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* tty: serial: fsl_lpuart: terminate DMA on buffer flushStefan Agner2015-02-021-0/+11
| | | | | | | | | | | | | | | On uart buffer flush, serial core resets the circular buffer. If a DMA transfer is in progress at that time, the callback lpuart_dma_tx_complete will move buffer's tail unconditionally, hence tail moves beyond head. Use the flush_buffer hook to terminate the DMA imeaditely and avoid lpuart_dma_tx_complete being called in this situation. This bug often showed up while shutdown and lead to duplicate serial console output. Signed-off-by: Stefan Agner <stefan@agner.ch> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* serial: fsl-lpuart: disable interrupt when suspendYuan Yao2015-02-021-0/+13
| | | | | | | | | | | For power management support, we should disable TX and TX interrupt so that kernel can prepare for deep sleep. Retain RX and RX interrupt for wakeup the kernel when receive the input character. Signed-off-by: Yuan Yao <yao.yuan@freescale.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* serial: fsl_lpuart: update RX timer on successful DMA transferStefan Agner2015-02-021-0/+1
| | | | | | | | | | | | | | | To end a DMA transfer which did not consume a whole buffer (e.g. one character only), a RX timer is used. When lots of data are received the DMA transfer will complete and setup another DMA transfer, which in turn might complete again. In this cases, it is not necessary to abort the DMA transfers using the RX timer. This change pushes the RX timer timeout into the future each time a DMA transfer completed. Aborting the DMA was not very harmful, since the next received character lead to setup of another RX DMA. Signed-off-by: Stefan Agner <stefan@agner.ch> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* serial: fsl_lpuart: move DMA channel request to probeStefan Agner2015-02-021-52/+44
| | | | | | | | | | | Move the DMA channel request to probe to avoid requesting the DMA channel on each opening of the ttyLPx device. This also fixes a potential issue that TX channel is not freed when only RX channel allocation fails. The DMA channels are now handled independently, so one could use UART with DMA only in TX direction for instance. Signed-off-by: Stefan Agner <stefan@agner.ch> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* serial: fsl_lpuart: avoid new transfer while DMA is runningStefan Agner2015-02-021-4/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When the UART is in DMA receive mode (RDMAS set) and one character just arrived while another interrupt is handled (e.g. TX), the RDRF (receiver data register full flag) is set due to the water level of 1. But since the DMA will take care of this character, there is no need to handle it by calling lpuart_prepare_rx. Handling it leads to adding the RX timeout timer twice: [ 74.336698] Kernel BUG at 80053070 [verbose debug info unavailable] [ 74.342999] Internal error: Oops - BUG: 0 [#1] ARM0:00.00 khungtaskd [ 74.347817] Modules linked in: 0 S 0.0 0.0 0:00.00 writeback [ 74.350926] CPU: 0 PID: 0 Comm: swapper Not tainted 3.19.0-rc3-00001-g39d78e2 #1788 [ 74.358617] Hardware name: Freescale Vybrid VF610 (Device Tree)t [ 74.364563] task: 807a7678 ti: 8079c000 task.ti: 8079c000 kblockd [ 74.370002] PC is at add_timer+0x24/0x28.0 0.0 0:00.09 kworker/u2:1 [ 74.373960] LR is at lpuart_int+0x15c/0x3d8 [ 74.378171] pc : [<80053070>] lr : [<802e0d88>] psr: a0010193 [ 74.378171] sp : 8079de10 ip : 8079de20 fp : 8079de1c [ 74.389694] r10: 807d44c0 r9 : 8688c300 r8 : 00000013 [ 74.394943] r7 : 20010193 r6 : 00000000 r5 : 000000a0 r4 : 86997210 [ 74.401498] r3 : ffffa7da r2 : 80817868 r1 : 86997210 r0 : 86997344 [ 74.408052] Flags: NzCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment kernel [ 74.415489] Control: 10c5387d Table: 8611c059 DAC: 00000015 [ 74.421265] Process swapper (pid: 0, stack limit = 0x8079c230) ... Solve this by only execute the receiver path (lpuart_prepare_rx) if the DMA receive mode (RDMAS) is not set. Also, make sure the flag is cleared on initialization, in case it has been left set. This can be best reproduced using UART as a serial console, then running top while dd'ing data into the terminal. Signed-off-by: Stefan Agner <stefan@agner.ch> Cc: stable <stable@vger.kernel.org> # 3.14 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* serial: fsl_lpuart: delete timer on shutdownStefan Agner2015-02-021-3/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If the serial port gets closed while a RX transfer is in progress, the timer might fire after the serial port shutdown finished. This leads in a NULL pointer dereference: [ 7.508324] Unable to handle kernel NULL pointer dereference at virtual address 00000000 [ 7.516590] pgd = 86348000 [ 7.519445] [00000000] *pgd=86179831, *pte=00000000, *ppte=00000000 [ 7.526145] Internal error: Oops: 17 [#1] ARM [ 7.530611] Modules linked in: [ 7.533876] CPU: 0 PID: 123 Comm: systemd Not tainted 3.19.0-rc3-00004-g5b11ea7 #1778 [ 7.541827] Hardware name: Freescale Vybrid VF610 (Device Tree) [ 7.547862] task: 861c3400 ti: 86ac8000 task.ti: 86ac8000 [ 7.553392] PC is at lpuart_timer_func+0x24/0xf8 [ 7.558127] LR is at lpuart_timer_func+0x20/0xf8 [ 7.562857] pc : [<802df99c>] lr : [<802df998>] psr: 600b0113 [ 7.562857] sp : 86ac9b90 ip : 86ac9b90 fp : 86ac9bbc [ 7.574467] r10: 80817180 r9 : 80817b98 r8 : 80817998 [ 7.579803] r7 : 807acee0 r6 : 86989000 r5 : 00000100 r4 : 86997210 [ 7.586444] r3 : 86ac8000 r2 : 86ac9bc0 r1 : 86997210 r0 : 00000000 [ 7.593085] Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user [ 7.600341] Control: 10c5387d Table: 86348059 DAC: 00000015 [ 7.606203] Process systemd (pid: 123, stack limit = 0x86ac8230) Setup the timer on UART startup which allows to delete the timer unconditionally on shutdown. This also saves the initialization on each transfer. Signed-off-by: Stefan Agner <stefan@agner.ch> Cc: stable <stable@vger.kernel.org> # 3.14 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Merge tag 'driver-core-3.19-rc1' of ↵Linus Torvalds2014-12-141-1/+0
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core update from Greg KH: "Here's the set of driver core patches for 3.19-rc1. They are dominated by the removal of the .owner field in platform drivers. They touch a lot of files, but they are "simple" changes, just removing a line in a structure. Other than that, a few minor driver core and debugfs changes. There are some ath9k patches coming in through this tree that have been acked by the wireless maintainers as they relied on the debugfs changes. Everything has been in linux-next for a while" * tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (324 commits) Revert "ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries" fs: debugfs: add forward declaration for struct device type firmware class: Deletion of an unnecessary check before the function call "vunmap" firmware loader: fix hung task warning dump devcoredump: provide a one-way disable function device: Add dev_<level>_once variants ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries ath: use seq_file api for ath9k debugfs files debugfs: add helper function to create device related seq_file drivers/base: cacheinfo: remove noisy error boot message Revert "core: platform: add warning if driver has no owner" drivers: base: support cpu cache information interface to userspace via sysfs drivers: base: add cpu_device_create to support per-cpu devices topology: replace custom attribute macros with standard DEVICE_ATTR* cpumask: factor out show_cpumap into separate helper function driver core: Fix unbalanced device reference in drivers_probe driver core: fix race with userland in device_add() sysfs/kernfs: make read requests on pre-alloc files use the buffer. sysfs/kernfs: allow attributes to request write buffer be pre-allocated. fs: sysfs: return EGBIG on write if offset is larger than file size ...
| * tty: serial: drop owner assignment from platform_driversWolfram Sang2014-10-201-1/+0
| | | | | | | | | | | | | | A platform_driver does not need to set an owner, it will be populated by the driver core. Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* | serial: fsl_lpuart: Remove unneeded registration messageFabio Estevam2014-11-071-4/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is no real value in displaying "serial: Freescale lpuart driver" in every boot. The uart_register_driver() can fail and even so the "serial: Freescale lpuart driver" will be displayed, which is not really helpful. This is particularly annoying when booting multi_v7_defconfig kernel on a SoC that is not a Vybrid/Layerscape and even though this message gets displayed. Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com> Acked-by: Jingchang Lu <jingchang.lu@freescale.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | serial: fsl_lpuart: Remove unneeded check for 'res'Fabio Estevam2014-11-071-4/+2
| | | | | | | | | | | | | | | | | | 'res' will be automatically checked inside devm_ioremap_resource(), so there is no need to explicitly perform a NULL check. Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com> Acked-by: Jingchang Lu <jingchang.lu@freescale.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | serial: fsl-lpuart: add lpuart32 power management supportJingchang Lu2014-11-061-0/+14
|/ | | | | | | | This adds 32-bit register lpuart32 power management support, this also updates the 8-bit register lpuart resume function. Signed-off-by: Jingchang Lu <jingchang.lu@freescale.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* tty: serial: fsl_lpuart: add 32-bit register interface supportJingchang Lu2014-07-171-8/+637
| | | | | | | | This add the 32-bit register version LPUART support with big-endian byte order. Signed-off-by: Jingchang Lu <jingchang.lu@freescale.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* serial: fsl_lpuart: calculate DMA burstStefan Agner2014-07-101-14/+13
| | | | | | | | | | | The DMA burst size must match the transmit FIFO depth in order to make sure all character are transmitted. This patch calculates DMA burst size by using FIFO depth rather than use the hardcoded 16 bytes. This is required since some UARTs (e.g. UART2 on Vybrid) have a FIFO depth of 8 bytes. Signed-off-by: Stefan Agner <stefan@agner.ch> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* serial: fsl_lpuart: move DMA RX timeout calculationStefan Agner2014-07-101-7/+11
| | | | | | | | | | | | | The DMA RX timeout calculation is done based on FIFO buffer size and port timeout when setting up DMA. However, both variables are not necessarily initialized at DMA initialization time, which can lead to a division by zero. Move the timeout calculation to set_termios where both variables are initialized. Signed-off-by: Stefan Agner <stefan@agner.ch> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* serial: treewide: Remove empty implementations of enable_ms()Alexander Shiyan2014-07-091-5/+0
| | | | | Signed-off-by: Alexander Shiyan <shc_work@mail.ru> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* serial: Fix IGNBRK handlingPeter Hurley2014-06-191-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If IGNBRK is set without either BRKINT or PARMRK set, some uart drivers send a 0x00 byte for BREAK without the TTYBREAK flag to the line discipline, when it should send either nothing or the TTYBREAK flag set. This happens because the read_status_mask masks out the BI condition, which uart_insert_char() then interprets as a normal 0x00 byte. SUS v3 is clear regarding the meaning of IGNBRK; Section 11.2.2, General Terminal Interface - Input Modes, states: "If IGNBRK is set, a break condition detected on input shall be ignored; that is, not put on the input queue and therefore not read by any process." Fix read_status_mask to include the BI bit if IGNBRK is set; the lsr status retains the BI bit if a BREAK is recv'd, which is subsequently ignored in uart_insert_char() when masked with the ignore_status_mask. Affected drivers: 8250 - all serial_txx9 mfd amba-pl010 amba-pl011 atmel_serial bfin_uart dz ip22zilog max310x mxs-auart netx-serial pnx8xxx_uart pxa sb1250-duart sccnxp serial_ks8695 sirfsoc_uart st-asc vr41xx_siu zs sunzilog fsl_lpuart sunsab ucc_uart bcm63xx_uart sunsu efm32-uart pmac_zilog mpsc msm_serial m32r_sio Unaffected drivers: omap-serial rp2 sa1100 imx icom Annotated for fixes: altera_uart mcf Drivers without break detection: 21285 xilinx-uartps altera_jtaguart apbuart arc-uart clps711x max3100 uartlite msm_serial_hs nwpserial lantiq vt8500_serial Unknown: samsung mpc52xx_uart bfin_sport_uart cpm_uart/core Fixes: Bugzilla #71651, '8250_core.c incorrectly handles IGNBRK flag' Reported-by: Ivan <athlon_@mail.ru> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* serial: fsl_lpuart: add DMA supportYuan Yao2014-02-181-12/+418
| | | | | | | | | | Add dma support for lpuart. This function depend on DMA driver. You can turn on it by write both the dmas and dma-name properties in dts node. Signed-off-by: Yuan Yao <yao.yuan@freescale.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* serial: fsl_lpuart: Return proper error on lpuart_serial_init error pathAxel Lin2013-07-261-1/+1
| | | | | Signed-off-by: Axel Lin <axel.lin@ingics.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* serial: fsl_lpuart: restore UARTCR2 after watermark setup is doneShawn Guo2013-07-261-0/+5
| | | | | | | | | | | | | | | Function lpuart_setup_watermark() clears some bits in register UARTCR2 before writing FIFO configuration registers as required by hardware. But it should restore UARTCR2 after that. Otherwise, we end up changing UARTCR2 register when setting up watermark, and that is not really desirable. At least, when low-level debug and earlyprint is enabled, serial console is broken due to it. Fix the problem by restoring UARTCR2 register at the end of function lpuart_setup_watermark(). Signed-off-by: Shawn Guo <shawn.guo@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* tty: serial: add Freescale lpuart driver supportJingchang Lu2013-06-081-0/+874
Add Freescale lpuart driver support. The lpuart device can be found on Vybrid VF610 and Layerscape LS-1 SoCs. Signed-off-by: Jingchang Lu <b35083@freescale.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-08 03:21:28 +0000