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authorRicardo Ribalda Delgado <ricardo.ribalda@gmail.com>2017-11-06 13:49:12 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2017-11-08 15:09:35 +0300
commit7ecc77011c6fb40d3eef7c6a0ebcec61e69b3ec3 (patch)
treefa409afa4b009b0146f4068fa302edb351e6d565 /drivers/tty
parente5656d43dce828bfcacbecd614e22355073e918b (diff)
downloadlinux-7ecc77011c6fb40d3eef7c6a0ebcec61e69b3ec3.tar.xz
serial: 8250_fintek: Return -EINVAL on invalid configuration
Hardware does not support having the same RTS level during RX and TX when RS485 mode is on (URA in Fintek terminology). The manufacturer has also confirmed that the delays are not enabled if the RS485 mode is not enabled. Therefore we should return -EINVAL if the user wants to have the same value for RTS_ON_SEND and RTS_AFTER_SEND. Cc: "Ji-Ze Hong (Peter Hong)" <hpeter@gmail.com> Cc: Lukas Wunner <lukas@wunner.de> Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty')
-rw-r--r--drivers/tty/serial/8250/8250_fintek.c17
1 files changed, 9 insertions, 8 deletions
diff --git a/drivers/tty/serial/8250/8250_fintek.c b/drivers/tty/serial/8250/8250_fintek.c
index be7029f2391e..6c7910d8e136 100644
--- a/drivers/tty/serial/8250/8250_fintek.c
+++ b/drivers/tty/serial/8250/8250_fintek.c
@@ -197,10 +197,17 @@ static int fintek_8250_rs485_config(struct uart_port *port,
if (!pdata)
return -EINVAL;
- if (rs485->flags & SER_RS485_ENABLED)
+ /* Hardware do not support same RTS level on send and receive */
+ if (!(rs485->flags & SER_RS485_RTS_ON_SEND) ==
+ !(rs485->flags & SER_RS485_RTS_AFTER_SEND))
+ return -EINVAL;
+
+ if (rs485->flags & SER_RS485_ENABLED) {
memset(rs485->padding, 0, sizeof(rs485->padding));
- else
+ config |= RS485_URA;
+ } else {
memset(rs485, 0, sizeof(*rs485));
+ }
rs485->flags &= SER_RS485_ENABLED | SER_RS485_RTS_ON_SEND |
SER_RS485_RTS_AFTER_SEND;
@@ -215,12 +222,6 @@ static int fintek_8250_rs485_config(struct uart_port *port,
config |= RXW4C_IRA;
}
- if ((!!(rs485->flags & SER_RS485_RTS_ON_SEND)) ==
- (!!(rs485->flags & SER_RS485_RTS_AFTER_SEND)))
- rs485->flags &= ~SER_RS485_ENABLED;
- else
- config |= RS485_URA;
-
if (rs485->flags & SER_RS485_RTS_ON_SEND)
config |= RTS_INVERT;