summaryrefslogtreecommitdiffstats
path: root/drivers/tty (follow)
Commit message (Collapse)AuthorAgeFilesLines
* Merge tag 'tty-4.18-rc1' of ↵Linus Torvalds2018-06-0626-293/+681
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty Pull tty/serial updates from Greg KH: "Here is the big tty/serial driver update for 4.18-rc1. There's nothing major here, just lots of serial driver updates. Full details are in the shortlog, nothing anything specific to call out here. All have been in linux-next for a while with no reported issues" * tag 'tty-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (55 commits) vt: Perform safe console erase only once serial: imx: disable UCR4_OREN on shutdown serial: imx: drop CTS/RTS handling from shutdown tty: fix typo in ASYNCB_FOURPORT comment serial: samsung: check DMA engine capabilities before using DMA mode tty: Fix data race in tty_insert_flip_string_fixed_flag tty: serial: msm_geni_serial: Fix TX infinite loop serial: 8250_dw: Fix runtime PM handling serial: 8250: omap: Fix idling of clocks for unused uarts tty: serial: drop ATH79 specific SoC symbols serial: 8250: Add missing rxtrig_bytes on Altera 16550 UART serial/aspeed-vuart: fix a couple mod_timer() calls serial: sh-sci: Use spin_{try}lock_irqsave instead of open coding version serial: 8250_of: Add IO space support tty/serial: atmel: use port->name as name in request_irq() serial: imx: dma_unmap_sg buffers on shutdown serial: imx: cleanup imx_uart_disable_dma() tty: serial: qcom_geni_serial: Add early console support tty: serial: qcom_geni_serial: Return IRQ_NONE for spurious interrupts tty: serial: qcom_geni_serial: Use iowrite32_rep to write to FIFO ...
| * vt: Perform safe console erase only onceNicolas Pitre2018-05-251-9/+7
| | | | | | | | | | | | | | | | | | | | | | | | Commit f8df13e0a9 ("tty: Clean console safely") added code to clear both the scrollback buffer and the screen with "\e[3J", then execution falls through into the code to simply clear the screen. This means scr_memsetw() and the console driver update callback are called twice on the whole screen buffer. Let's reorganize the code so the same work is not performed twice needlessly. Signed-off-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * serial: imx: disable UCR4_OREN on shutdownSebastian Reichel2018-05-251-1/+5
| | | | | | | | | | | | | | | | | | | | UCR4_OREN is (depending on the configuration) enabled in startup, but is never disabled. Fix this by disabling it in shutdown. Reported-by: Nandor Han <nandor.han@ge.com> Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk> Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * serial: imx: drop CTS/RTS handling from shutdownSebastian Reichel2018-05-251-1/+1
| | | | | | | | | | | | | | | | | | | | According to Documentation/serial/driver the shutdown function should not disable RTS, so drop it. Suggested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk> Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * serial: samsung: check DMA engine capabilities before using DMA modeMarek Szyprowski2018-05-241-4/+29
| | | | | | | | | | | | | | | | | | | | DMA engine driver might not always provide all the features needed by serial driver to properly operate in DMA mode, so check that before selecting DMA mode. Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * tty: Fix data race in tty_insert_flip_string_fixed_flagDaeRyong Jeong2018-05-141-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Unlike normal serials, in pty layer, there is no guarantee that multiple threads don't insert input characters at the same time. If it is happened, tty_insert_flip_string_fixed_flag can be executed concurrently. This can lead slab out-of-bounds write in tty_insert_flip_string_fixed_flag. Call sequences are as follows. CPU0 CPU1 n_tty_ioctl_helper n_tty_ioctl_helper __start_tty tty_send_xchar tty_wakeup pty_write n_hdlc_tty_wakeup tty_insert_flip_string n_hdlc_send_frames tty_insert_flip_string_fixed_flag pty_write tty_insert_flip_string tty_insert_flip_string_fixed_flag To fix the race, acquire port->lock in pty_write() before it inserts input characters to tty buffer. It prevents multiple threads from inserting input characters concurrently. The crash log is as follows: BUG: KASAN: slab-out-of-bounds in tty_insert_flip_string_fixed_flag+0xb5/ 0x130 drivers/tty/tty_buffer.c:316 at addr ffff880114fcc121 Write of size 1792 by task syz-executor0/30017 CPU: 1 PID: 30017 Comm: syz-executor0 Not tainted 4.8.0 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.8.2-0-g33fbe13 by qemu-project.org 04/01/2014 0000000000000000 ffff88011638f888 ffffffff81694cc3 ffff88007d802140 ffff880114fcb300 ffff880114fcc300 ffff880114fcb300 ffff88011638f8b0 ffffffff8130075c ffff88011638f940 ffff88007d802140 ffff880194fcc121 Call Trace: __dump_stack lib/dump_stack.c:15 [inline] dump_stack+0xb3/0x110 lib/dump_stack.c:51 kasan_object_err+0x1c/0x70 mm/kasan/report.c:156 print_address_description mm/kasan/report.c:194 [inline] kasan_report_error+0x1f7/0x4e0 mm/kasan/report.c:283 kasan_report+0x36/0x40 mm/kasan/report.c:303 check_memory_region_inline mm/kasan/kasan.c:292 [inline] check_memory_region+0x13e/0x1a0 mm/kasan/kasan.c:299 memcpy+0x37/0x50 mm/kasan/kasan.c:335 tty_insert_flip_string_fixed_flag+0xb5/0x130 drivers/tty/tty_buffer.c:316 tty_insert_flip_string include/linux/tty_flip.h:35 [inline] pty_write+0x7f/0xc0 drivers/tty/pty.c:115 n_hdlc_send_frames+0x1d4/0x3b0 drivers/tty/n_hdlc.c:419 n_hdlc_tty_wakeup+0x73/0xa0 drivers/tty/n_hdlc.c:496 tty_wakeup+0x92/0xb0 drivers/tty/tty_io.c:601 __start_tty.part.26+0x66/0x70 drivers/tty/tty_io.c:1018 __start_tty+0x34/0x40 drivers/tty/tty_io.c:1013 n_tty_ioctl_helper+0x146/0x1e0 drivers/tty/tty_ioctl.c:1138 n_hdlc_tty_ioctl+0xb3/0x2b0 drivers/tty/n_hdlc.c:794 tty_ioctl+0xa85/0x16d0 drivers/tty/tty_io.c:2992 vfs_ioctl fs/ioctl.c:43 [inline] do_vfs_ioctl+0x13e/0xba0 fs/ioctl.c:679 SYSC_ioctl fs/ioctl.c:694 [inline] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:685 entry_SYSCALL_64_fastpath+0x1f/0xbd Signed-off-by: DaeRyong Jeong <threeearcat@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * tty: serial: msm_geni_serial: Fix TX infinite loopEvan Green2018-05-141-10/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The GENI serial driver handled transmit by leaving stuff in the common circular buffer until it had completely caught up to the head, then clearing it out all at once. This is a suboptimal way to do transmit, as it leaves data in the circular buffer that could be freed. Moreover, the logic implementing it is wrong, and it is easy to get into a situation where the UART infinitely writes out the same buffer. I could reproduce infinite serial output of the same buffer by running dmesg, then hitting Ctrl-C. I believe what happened is xmit_size was something large, marching towards a larger value. Then the generic OS code flushed out the buffer and replaced it with two characters. Now the xmit_size is a large value marching towards a small value, which it wasn't expecting. The driver subtracts xmit_size (very large) from uart_circ_chars_pending (2), underflows, and repeats ad nauseum. The locking isn't wrong here, as the locks are held whenever the buffer is manipulated, it's just that the driver wasn't expecting the buffer to be flushed out from underneath it in between transmits. This change reworks transmit to grab what it can from the circular buffer, and then update ->tail, both fixing the underflow and freeing up space for a smoother circular experience. Signed-off-by: Evan Green <evgreen@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * serial: 8250_dw: Fix runtime PM handlingPhil Edworthy2018-05-141-0/+4
| | | | | | | | | | | | | | | | | | | | | | When using kgdb, you get an abort when accessing the UART registers. This is because the driver has already entered runtime PM and so turned off the bus clock needed to access the registers. To fix this, set the capability indicating Runtime PM is active while idle. Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * serial: 8250: omap: Fix idling of clocks for unused uartsTony Lindgren2018-05-141-1/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I noticed that unused UARTs won't necessarily idle properly always unless at least one byte tx transfer is done first. After some debugging I narrowed down the problem to the scr register dma configuration bits that need to be set before softreset for the clocks to idle. Unless we do this, the module clkctrl idlest bits may be set to 1 instead of 3 meaning the clock will never idle and is blocking deeper idle states for the whole domain. This might be related to the configuration done by the bootloader or kexec booting where certain configurations cause the 8250 or the clkctrl clock to jam in a way where setting of the scr bits and reset is needed to clear it. I've tried diffing the 8250 registers for the various modes, but did not see anything specific. So far I've only seen this on omap4 but I'm suspecting this might also happen on the other clkctrl using SoCs considering they already have a quirk enabled for UART_ERRATA_CLOCK_DISABLE. Let's fix the issue by configuring scr before reset for basic dma even if we don't use it. The scr register will be reset when we do softreset few lines after, and we restore scr on resume. We should do this for all the SoCs with UART_ERRATA_CLOCK_DISABLE quirk flag set since the ones with UART_ERRATA_CLOCK_DISABLE are all based using clkctrl similar to omap4. Looks like both OMAP_UART_SCR_DMAMODE_1 | OMAP_UART_SCR_DMAMODE_CTL bits are needed for the clkctrl to idle after a softreset. And we need to add omap4 to also use the UART_ERRATA_CLOCK_DISABLE for the related workaround to be enabled. This same compatible value will also be used for omap5. Fixes: cdb929e4452a ("serial: 8250_omap: workaround errata around idling UART after using DMA") Cc: Keerthy <j-keerthy@ti.com> Cc: Matthijs van Duin <matthijsvanduin@gmail.com> Cc: Sekhar Nori <nsekhar@ti.com> Cc: Tero Kristo <t-kristo@ti.com> Signed-off-by: Tony Lindgren <tony@atomide.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * tty: serial: drop ATH79 specific SoC symbolsJohn Crispin2018-05-141-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | QCA MIPS support is being converted to pure OF. As part of this we are dropping the SOC_AR* symbols. Additionally the SERIAL_AR933X style tty is also found on a few SoCs newer that the AR933x. This patch changes the dependency to ATH79, thus fixing the 2 issues described above. Signed-off-by: John Crispin <john@phrozen.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * serial: 8250: Add missing rxtrig_bytes on Altera 16550 UARTMarek Vasut2018-05-141-0/+3
| | | | | | | | | | | | | | | | | | | | | | The Altera 16550 UART core supports FCR Rx Trigger Level setting, but the port definition in the driver is missing the rxtrig_bytes array specifying the trigger levels. Add the array to make the Rx Trigger Level setting available on this type of 16550 UART. Signed-off-by: Marek Vasut <marex@denx.de> Cc: Thor Thayer <tthayer@opensource.altera.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * serial/aspeed-vuart: fix a couple mod_timer() callsDan Carpenter2018-05-141-2/+3
| | | | | | | | | | | | | | | | | | | | The "unthrottle_timeout" is HZ/10 but mod_timer() takes a the actual jiffie where you want it to timeout, not an offset. Fixes: 5909c0bf9c7a ("serial/aspeed-vuart: Implement quick throttle mechanism") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Jeremy Kerr <jk@ozlabs.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * serial: sh-sci: Use spin_{try}lock_irqsave instead of open coding versionDaniel Wagner2018-05-141-5/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 40f70c03e33a ("serial: sh-sci: add locking to console write function to avoid SMP lockup") copied the strategy to avoid locking problems in conjuncture with the console from the UART8250 driver. Instead using directly spin_{try}lock_irqsave(), local_irq_save() followed by spin_{try}lock() was used. While this is correct on mainline, for -rt it is a problem. spin_{try}lock() will check if it is running in a valid context. Since the local_irq_save() has already been executed, the context has changed and spin_{try}lock() will complain. The reason why spin_{try}lock() complains is that on -rt the spin locks are turned into mutexes and therefore can sleep. Sleeping with interrupts disabled is not valid. BUG: sleeping function called from invalid context at /home/wagi/work/rt/v4.4-cip-rt/kernel/locking/rtmutex.c:995 in_atomic(): 0, irqs_disabled(): 128, pid: 778, name: irq/76-eth0 CPU: 0 PID: 778 Comm: irq/76-eth0 Not tainted 4.4.126-test-cip22-rt14-00403-gcd03665c8318 #12 Hardware name: Generic RZ/G1 (Flattened Device Tree) Backtrace: [<c00140a0>] (dump_backtrace) from [<c001424c>] (show_stack+0x18/0x1c) r7:c06b01f0 r6:60010193 r5:00000000 r4:c06b01f0 [<c0014234>] (show_stack) from [<c01d3c94>] (dump_stack+0x78/0x94) [<c01d3c1c>] (dump_stack) from [<c004c134>] (___might_sleep+0x134/0x194) r7:60010113 r6:c06d3559 r5:00000000 r4:ffffe000 [<c004c000>] (___might_sleep) from [<c04ded60>] (rt_spin_lock+0x20/0x74) r5:c06f4d60 r4:c06f4d60 [<c04ded40>] (rt_spin_lock) from [<c02577e4>] (serial_console_write+0x100/0x118) r5:c06f4d60 r4:c06f4d60 [<c02576e4>] (serial_console_write) from [<c0061060>] (call_console_drivers.constprop.15+0x10c/0x124) r10:c06d2894 r9:c04e18b0 r8:00000028 r7:00000000 r6:c06d3559 r5:c06d2798 r4:c06b9914 r3:c02576e4 [<c0060f54>] (call_console_drivers.constprop.15) from [<c0062984>] (console_unlock+0x32c/0x430) r10:c06d30d8 r9:00000028 r8:c06dd518 r7:00000005 r6:00000000 r5:c06d2798 r4:c06d2798 r3:00000028 [<c0062658>] (console_unlock) from [<c0062e1c>] (vprintk_emit+0x394/0x4f0) r10:c06d2798 r9:c06d30ee r8:00000006 r7:00000005 r6:c06a78fc r5:00000027 r4:00000003 [<c0062a88>] (vprintk_emit) from [<c0062fa0>] (vprintk+0x28/0x30) r10:c060bd46 r9:00001000 r8:c06b9a90 r7:c06b9a90 r6:c06b994c r5:c06b9a3c r4:c0062fa8 [<c0062f78>] (vprintk) from [<c0062fb8>] (vprintk_default+0x10/0x14) [<c0062fa8>] (vprintk_default) from [<c009cd30>] (printk+0x78/0x84) [<c009ccbc>] (printk) from [<c025afdc>] (credit_entropy_bits+0x17c/0x2cc) r3:00000001 r2:decade60 r1:c061a5ee r0:c061a523 r4:00000006 [<c025ae60>] (credit_entropy_bits) from [<c025bf74>] (add_interrupt_randomness+0x160/0x178) r10:466e7196 r9:1f536000 r8:fffeef74 r7:00000000 r6:c06b9a60 r5:c06b9a3c r4:dfbcf680 [<c025be14>] (add_interrupt_randomness) from [<c006536c>] (irq_thread+0x1e8/0x248) r10:c006537c r9:c06cdf21 r8:c0064fcc r7:df791c24 r6:df791c00 r5:ffffe000 r4:df525180 [<c0065184>] (irq_thread) from [<c003fba4>] (kthread+0x108/0x11c) r10:00000000 r9:00000000 r8:c0065184 r7:df791c00 r6:00000000 r5:df791d00 r4:decac000 [<c003fa9c>] (kthread) from [<c00101b8>] (ret_from_fork+0x14/0x3c) r8:00000000 r7:00000000 r6:00000000 r5:c003fa9c r4:df791d00 Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Daniel Wagner <daniel.wagner@siemens.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * serial: 8250_of: Add IO space supportJohn Garry2018-05-141-27/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently the 8250_of driver only supports MEM IO type accesses. Some development boards (Huawei D03, specifically) require IO space access for 8250-compatible OF driver support, so add it. The modification is quite simple: just set the port iotype and associated flags depending on the device address resource type. Signed-off-by: John Garry <john.garry@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * tty/serial: atmel: use port->name as name in request_irq()Sebastian Andrzej Siewior2018-05-141-3/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I was puzzled while looking at /proc/interrupts and random things showed up between reboots. This occurred more often but I realised it later. The "correct" output should be: |38: 11861 atmel-aic5 2 Level ttyS0 but I saw sometimes |38: 6426 atmel-aic5 2 Level tty1 and accounted it wrongly as correct. This is use after free and the former example randomly got the "old" pointer which pointed to the same content. With SLAB_FREELIST_RANDOM and HARDENED I even got |38: 7067 atmel-aic5 2 Level E=Started User Manager for UID 0 or other nonsense. As it turns out the tty, pointer that is accessed in atmel_startup(), is freed() before atmel_shutdown(). It seems to happen quite often that the tty for ttyS0 is allocated and freed while ->shutdown is not invoked. I don't do anything special - just a systemd boot :) Use dev_name(&pdev->dev) as the IRQ name for request_irq(). This exists as long as the driver is loaded so no use-after-free here. Cc: stable@vger.kernel.org Fixes: 761ed4a94582 ("tty: serial_core: convert uart_close to use tty_port_close") Acked-by: Richard Genoud <richard.genoud@gmail.com> Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * serial: imx: dma_unmap_sg buffers on shutdownSebastian Reichel2018-05-141-2/+10
| | | | | | | | | | | | | | | | | | This properly unmaps DMA SG on device shutdown. Reported-by: Nandor Han <nandor.han@ge.com> Suggested-by: Nandor Han <nandor.han@ge.com> Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * serial: imx: cleanup imx_uart_disable_dma()Sebastian Reichel2018-05-141-7/+2
| | | | | | | | | | | | | | | | | | | | | | | | Remove unrelated CTSC/CTS disabling from imx_uart_disable_dma() and move it to imx_uart_shutdown(), which is the only user of the DMA disabling function. This should not change the driver's behaviour, but improves readability. After this change imx_uart_disable_dma() does the reverse thing of imx_uart_enable_dma(). Suggested-by: Nandor Han <nandor.han@ge.com> Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * tty: serial: qcom_geni_serial: Add early console supportKarthikeyan Ramasubramanian2018-05-141-2/+72
| | | | | | | | | | | | | | | | | | | | Add early console support in Qualcomm Technologies Inc., GENI based UART controller. Signed-off-by: Karthikeyan Ramasubramanian <kramasub@codeaurora.org> Signed-off-by: Girish Mahadevan <girishm@codeaurora.org> Reviewed-by: Stephen Boyd <swboyd@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * tty: serial: qcom_geni_serial: Return IRQ_NONE for spurious interruptsKarthikeyan Ramasubramanian2018-05-141-1/+1
| | | | | | | | | | | | | | | | | | | | | | Currently the driver returns IRQ_HANDLED when spurious interrupts happen. This is misleading. Fix the behavior by returning IRQ_NONE for spurious interrupts. Signed-off-by: Karthikeyan Ramasubramanian <kramasub@codeaurora.org> Reviewed-by: Matthias Kaehlcke <mka@chromium.org> Reviewed-by: Stephen Boyd <swboyd@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * tty: serial: qcom_geni_serial: Use iowrite32_rep to write to FIFOKarthikeyan Ramasubramanian2018-05-141-3/+4
| | | | | | | | | | | | | | | | | | | | Use iowrite32_rep to write to the hardware FIFO so that the code does not have to worry about the system endianness. Signed-off-by: Karthikeyan Ramasubramanian <kramasub@codeaurora.org> Reviewed-by: Matthias Kaehlcke <mka@chromium.org> Reviewed-by: Stephen Boyd <swboyd@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * tty: serial: qcom_geni_serial: Remove unnecessary memory barrierKarthikeyan Ramasubramanian2018-05-141-9/+7
| | | | | | | | | | | | | | | | | | | | | | | | While initiating TX, only the register reads need to be ordered. The register write order either is achieved due to data dependency or is not required. Use readl to achieve the read order and remove the unnecessary barrier. Signed-off-by: Karthikeyan Ramasubramanian <kramasub@codeaurora.org> Reviewed-by: Evan Green <evgreen@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * tty: serial: qcom_geni_serial: Initialize console port staticallyKarthikeyan Ramasubramanian2018-05-141-7/+9
| | | | | | | | | | | | | | | | | | | | Perform static initialization of console_port since its initial state has no run-time dependencies. Signed-off-by: Karthikeyan Ramasubramanian <kramasub@codeaurora.org> Reviewed-by: Matthias Kaehlcke <mka@chromium.org> Reviewed-by: Stephen Boyd <swboyd@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * tty: serial: qcom_geni_serial: Use min3 to find minimum of 3 valuesKarthikeyan Ramasubramanian2018-05-141-5/+1
| | | | | | | | | | | | | | | | | | Use min3 helper to calculate the minimum value of 3 variables. Signed-off-by: Karthikeyan Ramasubramanian <kramasub@codeaurora.org> Reviewed-by: Matthias Kaehlcke <mka@chromium.org> Reviewed-by: Stephen Boyd <swboyd@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * tty: serial: qcom_geni_serial: Cleanup redundant codeKarthikeyan Ramasubramanian2018-05-141-15/+6
| | | | | | | | | | | | | | | | | | | | | | | | * Remove redundant casting while using min_t * Remove redundant initialization of port_setup flag * Remove redundant error checking in get_tx_fifo_size * Remove logging redundant error code in debug messages * Remove redundant disable_irq before free_irq Signed-off-by: Karthikeyan Ramasubramanian <kramasub@codeaurora.org> Reviewed-by: Stephen Boyd <swboyd@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * tty: serial: qcom_geni_serial: Add comments for clarificationKarthikeyan Ramasubramanian2018-05-141-0/+12
| | | | | | | | | | | | | | | | | | * Document reason for newline character counting in console_write * Document reason for disabling IRQ in the system resume operation Signed-off-by: Karthikeyan Ramasubramanian <kramasub@codeaurora.org> Reviewed-by: Matthias Kaehlcke <mka@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * serial: samsung: fix maxburst parameter for DMA transactionsMarek Szyprowski2018-05-141-5/+2
| | | | | | | | | | | | | | | | | | | | | | | | The best granularity of residue that DMA engine can report is in the BURST units, so the serial driver must use MAXBURST = 1 and DMA_SLAVE_BUSWIDTH_1_BYTE if it relies on exact number of bytes transferred by DMA engine. Fixes: 62c37eedb74c ("serial: samsung: add dma reqest/release functions") Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Acked-by: Krzysztof Kozlowski <krzk@kernel.org> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * tty: serial: msm_serial: Add __maybe_unused to suspend/resume callbacksPascal Huerst2018-05-141-4/+2
| | | | | | | | | | | | | | | | As stated under "20) Conditional Compilation" in coding-style.rst. We shall rather use __maybe_unused than preprocessor macros in such cases. Signed-off-by: Pascal Huerst <pascal.huerst@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * earlycon: Remove hardcoded port->uartclk initialization in of_setup_earlyconMichal Simek2018-05-141-1/+0
| | | | | | | | | | | | | | | | | | There is no reason to initialize uartclk to BASE_BAUD * 16 for DT based systems. Signed-off-by: Michal Simek <michal.simek@xilinx.com> Tested-by: Matt Redfearn <matt.redfearn@mips.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * tty: pl011: Avoid spuriously stuck-off interruptsDave Martin2018-05-141-0/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 9b96fbacda34 ("serial: PL011: clear pending interrupts") clears the RX and receive timeout interrupts on pl011 startup, to avoid a screaming-interrupt scenario that can occur when the firmware or bootloader leaves these interrupts asserted. This has been noted as an issue when running Linux on qemu [1]. Unfortunately, the above fix seems to lead to potential misbehaviour if the RX FIFO interrupt is asserted _non_ spuriously on driver startup, if the RX FIFO is also already full to the trigger level. Clearing the RX FIFO interrupt does not change the FIFO fill level. In this scenario, because the interrupt is now clear and because the FIFO is already full to the trigger level, no new assertion of the RX FIFO interrupt can occur unless the FIFO is drained back below the trigger level. This never occurs because the pl011 driver is waiting for an RX FIFO interrupt to tell it that there is something to read, and does not read the FIFO at all until that interrupt occurs. Thus, simply clearing "spurious" interrupts on startup may be misguided, since there is no way to be sure that the interrupts are truly spurious, and things can go wrong if they are not. This patch instead clears the interrupt condition by draining the RX FIFO during UART startup, after clearing any potentially spurious interrupt. This should ensure that an interrupt will definitely be asserted if the RX FIFO subsequently becomes sufficiently full. The drain is done at the point of enabling interrupts only. This means that it will occur any time the UART is newly opened through the tty layer. It will not apply to polled-mode use of the UART by kgdboc: since that scenario cannot use interrupts by design, this should not matter. kgdboc will interact badly with "normal" use of the UART in any case: this patch makes no attempt to paper over such issues. This patch does not attempt to address the case where the RX FIFO fills faster than it can be drained: that is a pathological hardware design problem that is beyond the scope of the driver to work around. As a failsafe, the number of poll iterations for draining the FIFO is limited to twice the FIFO size. This will ensure that the kernel at least boots even if it is impossible to drain the FIFO for some reason. [1] [Qemu-devel] [Qemu-arm] [PATCH] pl011: do not put into fifo before enabled the interruption https://lists.gnu.org/archive/html/qemu-devel/2018-01/msg06446.html Reported-by: Wei Xu <xuwei5@hisilicon.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Linus Walleij <linus.walleij@linaro.org> Cc: Peter Maydell <peter.maydell@linaro.org> Fixes: 9b96fbacda34 ("serial: PL011: clear pending interrupts") Signed-off-by: Dave Martin <Dave.Martin@arm.com> Cc: stable <stable@vger.kernel.org> Tested-by: Wei Xu <xuwei5@hisilicon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * Merge 4.17-rc3 into tty-nextGreg Kroah-Hartman2018-04-308-27/+68
| |\ | | | | | | | | | | | | | | | We want the tty and serial driver fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | serial: uartps: Remove static port arrayMichal Simek2018-04-251-12/+4
| | | | | | | | | | | | | | | | | | | | | | | | Allocate uart port structure dynamically. Signed-off-by: Michal Simek <michal.simek@xilinx.com> Reviewed-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | serial: uartps: Move cnds_uart_get_port to probeMichal Simek2018-04-251-40/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | c&p this function to probe as preparation for removing cdns_uart_port[] static array. Signed-off-by: Michal Simek <michal.simek@xilinx.com> Reviewed-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | serial: uartps: Use dynamic array for console portMichal Simek2018-04-251-5/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Driver console functions are using pointer to static array with fixed size. There can be only one serial console at the time which is found by register_console(). register_console() is filling cons->index to port->line value. Signed-off-by: Michal Simek <michal.simek@xilinx.com> Reviewed-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | serial: uartps: Remove console_initcall from the driverMichal Simek2018-04-251-14/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | register_console() is called from uart_add_one_port()->uart_configure_port() that's why register_console() is called twice. This patch remove console_initcall to call register_console() only from one location. Also based on my tests cdns_uart_console_setup() is not called from the first register_console() call. Signed-off-by: Michal Simek <michal.simek@xilinx.com> Reviewed-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | sc16is7xx: Check for an error when the clock is enabled.Stefan Potyra2018-04-251-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When the clock is enabled, check if there is an error. Otherwise clk_get_rate() can be called without enabled clock. Found by Linux Driver Verification project (linuxtesting.org). Fixes: 0814e8d5da2b ("sc16is7xx: enable the clock") Signed-off-by: Stefan Potyra <Stefan.Potyra@elektrobit.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | tty: n_gsm: fix gsm_mux_net_start_xmit()'s return typeLuc Van Oostenryck2018-04-251-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The method ndo_start_xmit() is defined as returning an 'netdev_tx_t', which is a typedef for an enum type, but the implementation in this driver returns an 'int'. Fix this by returning 'netdev_tx_t' in this driver too. Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | serial: 8250_early: Setup divider when uartclk is passedMichal Simek2018-04-251-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | device->baud is always non zero value because it is checked already in early_serial8250_setup() before init_port is called. Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | tty/nozomi: fix inconsistent indentationJoey Pabalinas2018-04-251-38/+38
| | | | | | | | | | | | | | | | | | | | | Correct misaligned indentation and remove extraneous spaces. Signed-off-by: Joey Pabalinas <joeypabalinas@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | tty/nozomi: cleanup DUMP() macroJoey Pabalinas2018-04-251-13/+13
| | | | | | | | | | | | | | | | | | | | | | | | Replace snprint() with strscpy() and use min_t() instead of the conditional operator to clamp buffer length. Signed-off-by: Joey Pabalinas <joeypabalinas@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | tty: nozomi: fix spelling mistake in macro NOZOMI_STATE_UKNOWNColin Ian King2018-04-231-1/+1
| | | | | | | | | | | | | | | | | | | | | Rename NOZOMI_STATE_UKNOWN to NOZOMI_STATE_UNKNOWN (add missing N) Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | tty: ipwireless: Replace GFP_ATOMIC with GFP_KERNEL in ipwireless_network_createJia-Ju Bai2018-04-231-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ipwireless_network_create() is never called in atomic context. The call chain ending up at ipwireless_network_create() is: [1] ipwireless_network_create() <- config_ipwireless() <- ipwireless_attach() ipwireless_attach() is only set as ".probe" in struct pcmcia_driver. Despite never getting called from atomic context, ipwireless_network_create() calls kzalloc() with GFP_ATOMIC, which does not sleep for allocation. GFP_ATOMIC is not necessary and can be replaced with GFP_KERNEL, which can sleep and improve the possibility of sucessful allocation. This is found by a static analysis tool named DCNS written by myself. And I also manually check it. Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | serial/aspeed-vuart: Implement quick throttle mechanismJeremy Kerr2018-04-231-4/+101
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Although we populate the ->throttle and ->unthrottle UART operations, these may not be called until the ldisc has had a chance to schedule and check buffer space. This means that we may overflow the flip buffers without ever hitting the ldisc's throttle threshold. This change implements an interrupt-based throttle, where we check for space in the flip buffers before reading characters from the UART's FIFO. If there's no space available, we disable the RX interrupt and schedule a timer to check for space later. For this, we need an unlocked version of the set_throttle function to be able to change throttle state from the irq_handler, which already holds port->lock. This prevents a case where we drop characters under heavy RX load. Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Tested-by: Eddie James <eajames@linux.vnet.ibm.com> Tested-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | serial/aspeed-vuart: Implement rx throttlingJeremy Kerr2018-04-231-0/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The aspeed VUART runs at LPC bus frequency, rather than being restricted to a typical UART baud rate. This means that the VUART can receive a lot of data, which can overrun tty flip buffers, and/or cause a large amount of interrupt traffic. This change implements the uart_port->throttle & unthrottle callbacks, implemented by disabling the receiver line status & received data available IRQs. Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Tested-by: Eddie James <eajames@linux.vnet.ibm.com> Tested-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | serial/8250: export serial8250_read_charJeremy Kerr2018-04-231-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, we export serial8250_rx_chars, which does a whole bunch of reads from the 8250 data register, without any form of flow control between reads. An upcoming change to the aspeed vuart driver implements more fine-grained flow control in the interrupt handler, requiring character-at-a-time control over the rx path. This change exports serial8250_read_char to allow this. Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Tested-by: Eddie James <eajames@linux.vnet.ibm.com> Tested-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | serial: Introduce UPSTAT_SYNC_FIFO for synchronised FIFOsJeremy Kerr2018-04-231-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This change adds a flag to indicate that a UART is has an external means of synchronising its FIFO, without needing CTSRTS or XON/XOFF. This allows us to use the throttle/unthrottle callbacks, without having to claim other methods of flow control. Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Tested-by: Eddie James <eajames@linux.vnet.ibm.com> Tested-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | serial: Remove depends on HAS_DMA in case of platform dependencyGeert Uytterhoeven2018-04-231-4/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Remove dependencies on HAS_DMA where a Kconfig symbol depends on another symbol that implies HAS_DMA, and, optionally, on "|| COMPILE_TEST". In most cases this other symbol is an architecture or platform specific symbol, or PCI. Generic symbols and drivers without platform dependencies keep their dependencies on HAS_DMA, to prevent compiling subsystems or drivers that cannot work anyway. This simplifies the dependencies, and allows to improve compile-testing. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Reviewed-by: Mark Brown <broonie@kernel.org> Acked-by: Robin Murphy <robin.murphy@arm.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | earlycon: Initialize port->uartclk based on clock-frequency propertyMichal Simek2018-04-231-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On DT based platforms when current-speed property is present baudrate is setup. Also port->uartclk is initialized to bogus BASE_BAUD * 16 value. Drivers like uartps/ns16550 contain logic when baudrate and uartclk is used for baudrate calculation. The patch is reading optional clock-frequency property to replace bogus BASE_BAUD * 16 calculation to have proper baudrate calculation. Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | tty: serial: 8250: pass IRQ shared flag to UART portsKurt Kanzenbach2018-04-231-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On some systems IRQ lines between multiple UARTs might be shared. If so, the irqflags have to be configured accordingly. The reason is: The 8250 port startup code performs IRQ tests *before* the IRQ handler for that particular port is registered. This is performed in serial8250_do_startup(). This function checks whether IRQF_SHARED is configured and only then disables the IRQ line while testing. This test is performed upon each open() of the UART device. Imagine two UARTs share the same IRQ line: On is already opened and the IRQ is active. When the second UART is opened, the IRQ line has to be disabled while performing IRQ tests. Otherwise an IRQ might handler might be invoked, but the the IRQ itself cannot be handled, because the corresponding handler isn't registered, yet. That's because the 8250 code uses a chain-handler and invokes the corresponding port's IRQ handling rountines himself. Unfortunately this IRQF_SHARED flag isn't configured for UARTs probed via device tree even if the IRQs are shared. This way, the actual and shared IRQ line isn't disabled while performing tests and the kernel correctly detects a spurious IRQ. So, adding this flag to the DT probe solves the issue. Note: The UPF_SHARE_IRQ flag is configured unconditionally. Therefore, the IRQF_SHARED flag can be set unconditionally as well. Example stacktrace by performing echo 1 > /dev/ttyS2 on a non-patched system: |irq 85: nobody cared (try booting with the "irqpoll" option) | [...] |handlers: |[<ffff0000080fc628>] irq_default_primary_handler threaded [<ffff00000855fbb8>] serial8250_interrupt |Disabling IRQ #85 Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | serial: 8250: omap: Provide ability to enable/disable UART as wakeup sourceVignesh R2018-04-231-0/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Enable/Clear module level UART wakeup in UART_OMAP_WER register based on return value of device_may_wakeup() in .suspend(). This allows userspace to use sysfs to control the ability of UART to wakeup the system from deep sleep state. Register is restored back in .startup() call that happens as part of resume sequence. With this patch, userspace can control UART wakeup capability via sysfs: To enable wakeup capability: echo enabled > /sys/class/tty/ttyXX/device/power/wakeup For disabling wakeup capability: echo disabled > /sys/class/tty/ttyXX/device/power/wakeup Note that the UART wakeup events configured in the 8250 hardware only work for idle modes that do not cut off power for the UART. For deeper idle states, dedicated padconf wakeirqs must be used. Or in some cases the UART RX pin can be remuxed to GPIO input if the GPIO block stays powered. Signed-off-by: Vignesh R <vigneshr@ti.com> Tested-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | serial: 8250_dw: Limit dw8250_tx_wait_empty quirk to armada-38x devicesJoshua Scott2018-04-231-4/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The previous implementation has had a detrimental effect on devices using high bitrates (bluetooth), as the fifo being non-empty for a single check would result in a 10 µs delay. Limit the change to devices with the new "marvell,armada-38x-uart" compatible string. Also update the code to allow the first 1000 retries to not perform a delay. The maximum duration of retries has been increased to cover a worst-case seen on the Armada 385 SoC. "dmesg ; resize", will fill the buffer with text to output before doing a resize. At 9600 baud this took up to 13 ms to flush all characters and avoid some getting lost. Signed-off-by: Joshua Scott <joshua.scott@alliedtelesis.co.nz> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>