diff options
| author | Stefan Agner <stefan.agner@toradex.com> | 2018-04-17 11:34:34 +0200 |
|---|---|---|
| committer | Max Krummenacher <max.krummenacher@toradex.com> | 2018-06-21 09:28:22 +0200 |
| commit | ae78c40a12501108e0fee5c7d3b9d0e3e1a8214e (patch) | |
| tree | b87873fc25ee1ed27ed43c2e57f3afa67a95fbc9 | |
| parent | 3562e8d2b673fa9f9807c57ad33f743df0adbb65 (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 002eb91eca12..cd37a3a0f387 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -2069,8 +2069,16 @@ 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; } |