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| author | Jochen Mades <jochen@mades.net> | 2021-01-23 07:10:14 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-02-01 19:27:03 +0300 |
| commit | f0cb78064e1c1246394aeddbbf619198dd4ce980 (patch) | |
| tree | d5538ea44e1629eb11760a5ffa19def8a1a1c044 /drivers/tty/serial | |
| parent | 965bc27251f0eee9bb23c06dc708015630c97d1a (diff) | |
| download | linux-f0cb78064e1c1246394aeddbbf619198dd4ce980.tar.xz | |
serial: pl011: Fix incorrect rs485 RTS polarity on set_mctrl
commit 62f676ff7898f6c1bd26ce014564773a3dc00601 upstream.
Commit 8d479237727c ("serial: amba-pl011: add RS485 support") sought to
keep RTS deasserted on set_mctrl if rs485 is enabled. However it did so
only if deasserted RTS polarity is high. Fix it in case it's low.
Fixes: 8d479237727c ("serial: amba-pl011: add RS485 support")
Cc: stable@vger.kernel.org # v5.15+
Cc: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Signed-off-by: Jochen Mades <jochen@mades.net>
[lukas: copyedit commit message, add stable designation]
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Link: https://lore.kernel.org/r/85fa3323ba8c307943969b7343e23f34c3e652ba.1642909284.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty/serial')
| -rw-r--r-- | drivers/tty/serial/amba-pl011.c | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c index 6ec34260d6b1..da54f827c5ef 100644 --- a/drivers/tty/serial/amba-pl011.c +++ b/drivers/tty/serial/amba-pl011.c @@ -1615,8 +1615,12 @@ static void pl011_set_mctrl(struct uart_port *port, unsigned int mctrl) container_of(port, struct uart_amba_port, port); unsigned int cr; - if (port->rs485.flags & SER_RS485_ENABLED) - mctrl &= ~TIOCM_RTS; + if (port->rs485.flags & SER_RS485_ENABLED) { + if (port->rs485.flags & SER_RS485_RTS_AFTER_SEND) + mctrl &= ~TIOCM_RTS; + else + mctrl |= TIOCM_RTS; + } cr = pl011_read(uap, REG_CR); |