kernel/drivers/tty/serial, branch linux-4.1.y

Fix serial console on SNI RM400 machines

2018-05-23T01:36:27Z

[ Upstream commit e279e6d98e0cf2c2fe008b3c29042b92f0e17b1d ] sccnxp driver doesn't get the correct uart clock rate, if CONFIG_HAVE_CLOCK is disabled. Correct usage of clk API to make it work with/without it. Fixes: 90efa75f7ab0 (serial: sccnxp: Using CLK API for getting UART clock) Suggested-by: Russell King - ARM Linux Signed-off-by: Thomas Bogendoerfer Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

serial: 8250: omap: Disable DMA for console UART

2018-05-23T01:36:24Z

[ Upstream commit 84b40e3b57eef1417479c00490dd4c9f6e5ffdbc ] Kernel always writes log messages to console via serial8250_console_write()->serial8250_console_putchar() which directly accesses UART_TX register _without_ using DMA. But, if other processes like systemd using same UART port, then these writes are handled by a different code flow using 8250_omap driver where there is provision to use DMA. It seems that it is possible that both DMA and CPU might simultaneously put data to UART FIFO and lead to potential loss of data due to FIFO overflow and weird data corruption. This happens when both kernel console and userspace tries to write simultaneously to the same UART port. Therefore, disable DMA on kernel console port to avoid potential race between CPU and DMA. Signed-off-by: Vignesh R Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

serial: 8250_pci: Add Brainboxes UC-260 4 port serial device

2018-03-21T03:49:54Z

[ Upstream commit 9f2068f35729948bde84d87a40d135015911345d ] Add PCI ids for two variants of Brainboxes UC-260 quad port PCI serial cards. Suggested-by: Andy Shevchenko Signed-off-by: Nikola Ciprich Cc: stable Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

tty/serial: atmel: add new version check for usart

2018-03-21T03:49:53Z

[ Upstream commit fd63a8903a2c40425a9811c3371dd4d0f42c0ad3 ] On our at91sam9260 based board the usart0 and usart1 ports report their versions (ATMEL_US_VERSION) as 0x10302. This version is not included in the current checks in the driver. Signed-off-by: Jonas Danielsson Acked-by: Richard Genoud Acked-by: Nicolas Ferre Cc: stable Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

serial: sh-sci: prevent lockup on full TTY buffers

2018-03-21T03:49:53Z

[ Upstream commit 7842055bfce4bf0170d0f61df8b2add8399697be ] When the TTY buffers fill up to the configured maximum, a system lockup occurs: [ 598.820128] INFO: rcu_preempt detected stalls on CPUs/tasks: [ 598.825796] 0-...!: (1 GPs behind) idle=5a6/2/0 softirq=1974/1974 fqs=1 [ 598.832577] (detected by 3, t=62517 jiffies, g=296, c=295, q=126) [ 598.838755] Task dump for CPU 0: [ 598.841977] swapper/0 R running task 0 0 0 0x00000022 [ 598.849023] Call trace: [ 598.851476] __switch_to+0x98/0xb0 [ 598.854870] (null) This can be prevented by doing a dummy read of the RX data register. This issue affects both HSCIF and SCIF ports. Reported for R-Car H3 ES2.0; reproduced and fixed on H3 ES1.1. Probably affects other R-Car platforms as well. Reported-by: Yoshihiro Shimoda Signed-off-by: Ulrich Hecht Reviewed-by: Geert Uytterhoeven Cc: stable Tested-by: Nguyen Viet Dung Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

serial: 8250_fintek: Fix rs485 disablement on invalid ioctl()

2018-01-17T17:55:17Z

[ Upstream commit 3236a965486ba0c6043cf2c7b51943d8b382ae29 ] This driver's ->rs485_config callback checks if SER_RS485_RTS_ON_SEND and SER_RS485_RTS_AFTER_SEND have the same value. If they do, it means the user has passed in invalid data with the TIOCSRS485 ioctl() since RTS must have a different polarity when sending and when not sending. In this case, rs485 mode is not enabled (the RS485_URA bit is not set in the RS485 Enable Register) and this is supposed to be signaled back to the user by clearing the SER_RS485_ENABLED bit in struct serial_rs485 ... except a missing tilde character is preventing that from happening. Fixes: 28e3fb6c4dce ("serial: Add support for Fintek F81216A LPC to 4 UART") Cc: Ricardo Ribalda Delgado Cc: "Ji-Ze Hong (Peter Hong)" Signed-off-by: Lukas Wunner Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

serial: 8250_pci: Add Amazon PCI serial device ID

2018-01-17T17:55:17Z

[ Upstream commit 3bfd1300abfe3adb18e84a89d97a0e82a22124bb ] This device will be used in future Amazon EC2 instances as the primary serial port (i.e., data sent to this port will be available via the GetConsoleOuput [1] EC2 API). [1] http://docs.aws.amazon.com/AWSEC2/latest/APIReference/API_GetConsoleOutput.html Cc: stable Signed-off-by: Matt Wilson Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

8250_pci: Fix potential use-after-free in error path

2018-01-17T17:55:16Z

[ Upstream commit c130b666a9a711f985a0a44b58699ebe14bb7245 ] Commit f209fa03fc9d ("serial: 8250_pci: Detach low-level driver during PCI error recovery") introduces a potential use-after-free in case the pciserial_init_ports call in serial8250_io_resume fails, which may happen if a memory allocation fails or if the .init quirk failed for whatever reason). If this happen, further pci_get_drvdata will return a pointer to freed memory. This patch reworks the PCI recovery resume hook to restore the old priv structure in this case, which should be ok, since the ports were already detached. Such error during recovery causes us to give up on the recovery. Fixes: f209fa03fc9d ("serial: 8250_pci: Detach low-level driver during PCI error recovery") Reported-by: Michal Suchanek Signed-off-by: Gabriel Krisman Bertazi Signed-off-by: Guilherme G. Piccoli Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

serial: 8250_pci: Detach low-level driver during PCI error recovery

2018-01-17T17:31:54Z

[ Upstream commit f209fa03fc9d131b3108c2e4936181eabab87416 ] During a PCI error recovery, like the ones provoked by EEH in the ppc64 platform, all IO to the device must be blocked while the recovery is completed. Current 8250_pci implementation only suspends the port instead of detaching it, which doesn't prevent incoming accesses like TIOCMGET and TIOCMSET calls from reaching the device. Those end up racing with the EEH recovery, crashing it. Similar races were also observed when opening the device and when shutting it down during recovery. This patch implements a more robust IO blockage for the 8250_pci recovery by unregistering the port at the beginning of the procedure and re-adding it afterwards. Since the port is detached from the uart layer, we can be sure that no request will make through to the device during recovery. This is similar to the solution used by the JSM serial driver. I thank Peter Hurley for valuable input on this one over one year ago. Signed-off-by: Gabriel Krisman Bertazi Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

serial: omap: Fix EFR write on RTS deassertion

2017-12-07T02:20:15Z

[ Upstream commit 2a71de2f7366fb1aec632116d0549ec56d6a3940 ] Commit 348f9bb31c56 ("serial: omap: Fix RTS handling") sought to enable auto RTS upon manual RTS assertion and disable it on deassertion. However it seems the latter was done incorrectly, it clears all bits in the Extended Features Register *except* auto RTS. Fixes: 348f9bb31c56 ("serial: omap: Fix RTS handling") Cc: Peter Hurley Cc: stable Signed-off-by: Lukas Wunner Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin