linux/drivers/tty/serial/sh-sci.c, branch v4.14

serial: sh-sci: use of_property_read_bool()

2017-08-28T18:51:20Z

Use more compact of_property_read_bool() call for a boolean property instead of of_find_property() call in sci_parse_dt(). Signed-off-by: Sergei Shtylyov Reviewed-by: Geert Uytterhoeven Signed-off-by: Greg Kroah-Hartman

serial: sh-sci: Uninitialized variables in sysfs files

2017-07-17T11:19:19Z

The kstrtol() function returns -ERANGE as well as -EINVAL so these tests are not enough. It's not a super serious bug, but my static checker correctly complains that the "r" variable might be used uninitialized. Fixes: 5d23188a473d ("serial: sh-sci: make RX FIFO parameters tunable via sysfs") Signed-off-by: Dan Carpenter Cc: stable Signed-off-by: Greg Kroah-Hartman

serial: sh-sci: Update warning message in sci_request_dma_chan()

2017-05-24T13:15:56Z

The commit below changed a function call from dma_request_slave_channel_compat() to dma_request_slave_channel(), but forgot to update the printed failure message. Fixes: 219fb0c1436e4893 ("serial: sh-sci: Remove the platform data dma slave rx/tx channel IDs") Signed-off-by: Geert Uytterhoeven Signed-off-by: Greg Kroah-Hartman

serial: sh-sci: Move uart_register_driver call to device probe

2017-05-18T14:19:16Z

uart_register_driver call binds the driver to a specific device node through tty_register_driver call. This should typically happen during device probe call. In a multiplatform scenario, it is possible that multiple serial drivers are part of the kernel. Currently the driver registration fails if multiple serial drivers with overlapping major/minor numbers are included. Signed-off-by: Sjoerd Simons Signed-off-by: Greg Kroah-Hartman

serial: sh-sci: Fix race condition causing garbage during shutdown

2017-05-18T14:19:16Z

If DMA is enabled and used, a burst of old data may be seen on the serial console during "poweroff" or "reboot". uart_flush_buffer() clears the circular buffer, but sci_port.tx_dma_len is not reset. This leads to a circular buffer overflow, dumping (UART_XMIT_SIZE - sci_port.tx_dma_len) bytes. To fix this, add a .flush_buffer() callback that resets sci_port.tx_dma_len. Inspired by commit 31ca2c63fdc0aee7 ("tty/serial: atmel: fix race condition (TX+DMA)"). Signed-off-by: Geert Uytterhoeven Signed-off-by: Greg Kroah-Hartman

serial: sh-sci: Fix (AUTO)RTS in sci_init_pins()

2017-03-31T13:29:06Z

If a UART has dedicated RTS/CTS pins, and hardware control flow is disabled (or AUTORTS is not yet effective), changing any serial port configuration deasserts RTS, as .set_termios() calls sci_init_pins(). To fix this, consider the current (AUTO)RTS state when (re)initializing the pins. Note that for SCIFA/SCIFB, AUTORTS needs explicit configuration of the RTS# pin function, while (H)SCIF handles this automatically. Fixes: d2b9775d795ec05f ("serial: sh-sci: Correct pin initialization on (H)SCIF") Fixes: e9d7a45a03991349 ("serial: sh-sci: Add pin initialization for SCIFA/SCIFB") Signed-off-by: Geert Uytterhoeven Signed-off-by: Greg Kroah-Hartman

serial: sh-sci: Fix late enablement of AUTORTS

2017-03-31T13:29:05Z

When changing hardware control flow for a UART with dedicated RTS/CTS pins, the new AUTORTS state is not immediately reflected in the hardware, but only when RTS is raised. However, the serial core does not call .set_mctrl() after .set_termios(), hence AUTORTS may only become effective when the port is closed, and reopened later. Note that this problem does not happen when manually using stty to change CRTSCTS, as AUTORTS will work fine on next open. To fix this, call .set_mctrl() from .set_termios() when dedicated RTS/CTS pins are present, to refresh the AUTORTS or RTS state. This is similar to what other drivers supporting AUTORTS do (e.g. omap-serial). Reported-by: Baumann, Christoph (C.) Fixes: 33f50ffc253854cf ("serial: sh-sci: Fix support for hardware-assisted RTS/CTS") Signed-off-by: Geert Uytterhoeven Signed-off-by: Greg Kroah-Hartman

serial: sh-sci: Fix hang in sci_reset()

2017-03-31T13:29:05Z

When the .set_termios() callback resets the UART, it first waits (busy loops) until all characters in the transmit FIFO have been transmitted, to prevent a port configuration change from impacting these characters. However, if the UART has dedicated RTS/CTS hardware flow control enabled, these characters may have been stuck in the FIFO due to CTS not being asserted by the remote side. - When a new user opens the port, .set_termios() is called while transmission is still disabled, leading to an infinite loop: NMI watchdog: BUG: soft lockup - CPU#0 stuck for 22s! - When an active user changes port configuration without waiting for the draining of the transmit FIFO, this may also block indefinitely, until CTS is asserted by the remote side. This has been observed with SCIFA (on r8a7740/armadillo), and SCIFB and HSCIF (on r8a7791/koelsch). To fix this, remove the code that waits for the draining of the transmit FIFO. Signed-off-by: Geert Uytterhoeven Signed-off-by: Greg Kroah-Hartman

serial: sh-sci: Fix panic when serial console and DMA are enabled

2017-03-14T02:59:04Z

This patch fixes an issue that kernel panic happens when DMA is enabled and we press enter key while the kernel booting on the serial console. * An interrupt may occur after sci_request_irq(). * DMA transfer area is initialized by setup_timer() in sci_request_dma() and used in interrupt. If an interrupt occurred between sci_request_irq() and setup_timer() in sci_request_dma(), DMA transfer area has not been initialized yet. So, this patch changes the order of sci_request_irq() and sci_request_dma(). Fixes: 73a19e4c0301 ("serial: sh-sci: Add DMA support.") Signed-off-by: Takatoshi Akiyama [Shimoda changes the commit log] Signed-off-by: Yoshihiro Shimoda Signed-off-by: Greg Kroah-Hartman

serial: sh-sci: fix hardware RX trigger level setting

2017-02-10T14:10:16Z

1. Do not set the RX trigger level for software timeout devices on reset; there is no timeout by default, and data will rot. 2. Do set the RX trigger level for hardware timeout devices when set via sysfs attribute. Fixes SCIFA-type serial consoles. Signed-off-by: Ulrich Hecht Tested-by: Geert Uytterhoeven Signed-off-by: Greg Kroah-Hartman