kernel/linux.git/drivers/tty, branch v4.19.39

serial: ar933x_uart: Fix build failure with disabled console

2019-05-04T07:20:13+00:00

[ Upstream commit 72ff51d8dd262d1fef25baedc2ac35116435be47 ] Andrey has reported on OpenWrt's bug tracking system[1], that he currently can't use ar93xx_uart as pure serial UART without console (CONFIG_SERIAL_8250_CONSOLE and CONFIG_SERIAL_AR933X_CONSOLE undefined), because compilation ends with following error: ar933x_uart.c: In function 'ar933x_uart_console_write': ar933x_uart.c:550:14: error: 'struct uart_port' has no member named 'sysrq' So this patch moves all the code related to console handling behind series of CONFIG_SERIAL_AR933X_CONSOLE ifdefs. 1. https://bugs.openwrt.org/index.php?do=details&task_id=2152 Cc: Greg Kroah-Hartman Cc: Jiri Slaby Cc: Andrey Batyiev Reported-by: Andrey Batyiev Tested-by: Andrey Batyiev Signed-off-by: Petr Štetiar Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin (Microsoft)

sc16is7xx: missing unregister/delete driver on error in sc16is7xx_init()

2019-05-04T07:20:13+00:00

[ Upstream commit ac0cdb3d990108df795b676cd0d0e65ac34b2273 ] Add the missing uart_unregister_driver() and i2c_del_driver() before return from sc16is7xx_init() in the error handling case. Signed-off-by: Mao Wenan Reviewed-by: Vladimir Zapolskiy Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin (Microsoft)

vt: fix cursor when clearing the screen

2019-04-27T07:36:36+00:00

commit b2ecf00631362a83744e5ec249947620db5e240c upstream. The patch a6dbe4427559 ("vt: perform safe console erase in the right order") introduced a bug. The conditional do_update_region() was replaced by a call to update_region() that does contain the conditional already, but with unwanted extra side effects such as restoring the cursor drawing. In order to reproduce the bug: - use framebuffer console with the AMDGPU driver - type "links" to start the console www browser - press 'q' and space to exit links Now the cursor will be permanently visible in the center of the screen. It will stay there until something overwrites it. The bug goes away if we change update_region() back to the conditional do_update_region(). [ nico: reworded changelog ] Signed-off-by: Mikulas Patocka Reviewed-by: Nicolas Pitre Cc: stable@vger.kernel.org Fixes: a6dbe4427559 ("vt: perform safe console erase in the right order") Signed-off-by: Greg Kroah-Hartman

serial: sh-sci: Fix HSCIF RX sampling point calculation

2019-04-27T07:36:36+00:00

commit ace965696da2611af759f0284e26342b7b6cec89 upstream. There are several issues with the formula used for calculating the deviation from the intended rate: 1. While min_err and last_stop are signed, srr and baud are unsigned. Hence the signed values are promoted to unsigned, which will lead to a bogus value of deviation if min_err is negative, 2. Srr is the register field value, which is one less than the actual sampling rate factor, 3. The divisions do not use rounding. Fix this by casting unsigned variables to int, adding one to srr, and using a single DIV_ROUND_CLOSEST(). Fixes: 63ba1e00f178a448 ("serial: sh-sci: Support for HSCIF RX sampling point adjustment") Signed-off-by: Geert Uytterhoeven Reviewed-by: Mukesh Ojha Cc: stable Reviewed-by: Ulrich Hecht Signed-off-by: Greg Kroah-Hartman

serial: sh-sci: Fix HSCIF RX sampling point adjustment

2019-04-27T07:36:36+00:00

commit 6b87784b53592a90d21576be8eff688b56d93cce upstream. The calculation of the sampling point has min() and max() exchanged. Fix this by using the clamp() helper instead. Fixes: 63ba1e00f178a448 ("serial: sh-sci: Support for HSCIF RX sampling point adjustment") Signed-off-by: Geert Uytterhoeven Reviewed-by: Ulrich Hecht Reviewed-by: Wolfram Sang Acked-by: Dirk Behme Cc: stable Reviewed-by: Simon Horman Signed-off-by: Greg Kroah-Hartman

serial: uartps: console_setup() can't be placed to init section

2019-04-20T07:16:01+00:00

[ Upstream commit 4bb1ce2350a598502b23088b169e16b43d4bc639 ] When console device is rebinded, console_setup() is called again. But marking it as __init means that function will be clear after boot is complete. If console device is binded again console_setup() is not found and error "Unable to handle kernel paging request at virtual address" is reported. Signed-off-by: Michal Simek Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

tty: ldisc: add sysctl to prevent autoloading of ldiscs

2019-04-17T06:38:47+00:00

commit 7c0cca7c847e6e019d67b7d793efbbe3b947d004 upstream. By default, the kernel will automatically load the module of any line dicipline that is asked for. As this sometimes isn't the safest thing to do, provide a sysctl to disable this feature. By default, we set this to 'y' as that is the historical way that Linux has worked, and we do not want to break working systems. But in the future, perhaps this can default to 'n' to prevent this functionality. Signed-off-by: Greg Kroah-Hartman Reviewed-by: Theodore Ts'o Signed-off-by: Greg Kroah-Hartman

tty: increase the default flip buffer limit to 2*640K

2019-04-05T20:33:13+00:00

[ Upstream commit 7ab57b76ebf632bf2231ccabe26bea33868118c6 ] We increase the default limit for buffer memory allocation by a factor of 10 to 640K to prevent data loss when using fast serial interfaces. For example when using RS485 without flow-control at speeds of 1Mbit/s an upwards we've run into problems such as applications being too slow to read out this buffer (on embedded devices based on imx53 or imx6). If you want to write transmitted data to a slow SD card and thus have realtime requirements, this limit can become a problem. That shouldn't be the case and 640K buffers fix such problems for us. This value is a maximum limit for allocation only. It has no effect on systems that currently run fine. When transmission is slow enough applications and hardware can keep up and increasing this limit doesn't change anything. It only _allows_ to allocate more than 2*64K in cases we currently fail to allocate memory despite having some. Signed-off-by: Manfred Schlaegl Signed-off-by: Martin Kepplinger Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

serial: 8250_pxa: honor the port number from devicetree

2019-04-05T20:33:01+00:00

[ Upstream commit fe9ed6d2483fda55465f32924fb15bce0fac3fac ] Like the other OF-enabled drivers, use the port number from the firmware if the devicetree specifies an alias: aliases { ... serial2 = &uart2; /* Should be ttyS2 */ } This is how the deprecated pxa.c driver behaved, switching to 8250_pxa messes up the numbering. Signed-off-by: Lubomir Rintel Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

tty/serial: atmel: RS485 HD w/DMA: enable RX after TX is stopped

2019-04-05T20:32:55+00:00

commit 69646d7a3689fbe1a65ae90397d22ac3f1b8d40f upstream. In half-duplex operation, RX should be started after TX completes. If DMA is used, there is a case when the DMA transfer completes but the TX FIFO is not emptied, so the RX cannot be restarted just yet. Use a boolean variable to store this state and rearm TX interrupt mask to be signaled again that the transfer finished. In interrupt transmit handler this variable is used to start RX. A warning message is generated if RX is activated before TX fifo is cleared. Fixes: b389f173aaa1 ("tty/serial: atmel: RS485 half duplex w/DMA: enable RX after TX is done") Signed-off-by: Razvan Stefanescu Acked-by: Richard Genoud Cc: stable Signed-off-by: Greg Kroah-Hartman