diff options
| author | Christoph Vogtländer <c.vogtlaender@sigma-surface-science.com> | 2019-09-04 14:17:46 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-09-05 09:57:44 +0200 |
| commit | 7d4f881ff1fb327e96fc36a58c4f0b6482ea453d (patch) | |
| tree | 14b27d97b99b74189f04a140bf9cef98f038884d /drivers/tty | |
| parent | 5a8c296f5362fffc9da5da10eef01cf0b9b4ac7f (diff) | |
serial: max310x: turn off transmitter before activating AutoCTS or auto transmitter flow control
As documented in the data-sheet, the transmitter must be disabled before
activating AutoCTS or auto transmitter flow control. Accordingly, the
transmitter must be enabled after AutoCTS or auto transmitter flow
control gets deactivated.
Signed-off-by: Christoph Vogtländer <c.vogtlaender@sigma-surface-science.com>
Link: https://lore.kernel.org/r/20190904121746.4641-1-c.vogtlaender@sigma-surface-science.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty')
| -rw-r--r-- | drivers/tty/serial/max310x.c | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/drivers/tty/serial/max310x.c b/drivers/tty/serial/max310x.c index aed19c688beb..8434bd5a8ec7 100644 --- a/drivers/tty/serial/max310x.c +++ b/drivers/tty/serial/max310x.c @@ -956,6 +956,15 @@ static void max310x_set_termios(struct uart_port *port, max310x_port_write(port, MAX310X_XON1_REG, termios->c_cc[VSTART]); max310x_port_write(port, MAX310X_XOFF1_REG, termios->c_cc[VSTOP]); + /* Disable transmitter before enabling AutoCTS or auto transmitter + * flow control + */ + if (termios->c_cflag & CRTSCTS || termios->c_iflag & IXOFF) { + max310x_port_update(port, MAX310X_MODE1_REG, + MAX310X_MODE1_TXDIS_BIT, + MAX310X_MODE1_TXDIS_BIT); + } + port->status &= ~(UPSTAT_AUTOCTS | UPSTAT_AUTORTS | UPSTAT_AUTOXOFF); if (termios->c_cflag & CRTSCTS) { @@ -974,6 +983,15 @@ static void max310x_set_termios(struct uart_port *port, } max310x_port_write(port, MAX310X_FLOWCTRL_REG, flow); + /* Enable transmitter after disabling AutoCTS and auto transmitter + * flow control + */ + if (!(termios->c_cflag & CRTSCTS) && !(termios->c_iflag & IXOFF)) { + max310x_port_update(port, MAX310X_MODE1_REG, + MAX310X_MODE1_TXDIS_BIT, + 0); + } + /* Get baud rate generator configuration */ baud = uart_get_baud_rate(port, termios, old, port->uartclk / 16 / 0xffff, |