diff options
| author | Stefan Agner <stefan.agner@toradex.com> | 2018-04-17 11:34:34 +0200 |
|---|---|---|
| committer | Marcel Ziswiler <marcel.ziswiler@toradex.com> | 2018-12-24 01:27:32 +0100 |
| commit | 72919eb5f9e7a9aeb5fc1c2aa694b07994fb5a8d (patch) | |
| tree | 51b06bd406edb37be4ab05661a7da2c9da0349c9 | |
| parent | 3657cc7fe11427f27b189ffa7a83e91f4308a8db (diff) | |
serial: imx: add RS-485 device tree properties
Add device tree properties to influence RTS polarity and whether
the receiver is enabled during transmission (rs485-rts-active-low,
rs485-rx-during-tx).
This aligns with behavior with upstream Linux, where RTS is active
high by default (SER_RS485_RTS_AFTER_SEND) and the receiver is
disabled by default when using RS485 (SER_RS485_RX_DURING_TX).
Note that for Toradex hardware both properties are required, hence
using RS-485 on Toradex Carrier Boards requires the following
properties being specified in the device tree:
linux,rs485-enabled-at-boot-time;
rs485-rts-active-low;
rs485-rx-during-tx;
Signed-off-by: Stefan Agner <stefan.agner@toradex.com>
Acked-by: Max Krummenacher <max.krummenacher@toradex.com>
| -rw-r--r-- | drivers/tty/serial/imx.c | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index 39056519a293..7b5541695308 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -2082,8 +2082,16 @@ static int serial_imx_probe_dt(struct imx_port *sport, if (of_get_property(np, "fsl,dte-mode", NULL)) sport->dte_mode = 1; - if (of_property_read_bool(np, "linux,rs485-enabled-at-boot-time")) { + sport->port.rs485.flags |= SER_RS485_RTS_AFTER_SEND; + + if (of_property_read_bool(np, "linux,rs485-enabled-at-boot-time")) sport->port.rs485.flags |= SER_RS485_ENABLED; + + if (of_property_read_bool(np, "rs485-rx-during-tx")) + sport->port.rs485.flags |= SER_RS485_RX_DURING_TX; + + if (of_property_read_bool(np, "rs485-rts-active-low")) { + sport->port.rs485.flags &= ~SER_RS485_RTS_ON_SEND; sport->port.rs485.flags |= SER_RS485_RTS_AFTER_SEND; } |