639949a703
Since commit 79d0224f6bf2 ("tty: serial: imx: Handle RS485 DE signal
active high") RS485 reception no longer works after a transmission.
The following scenario shows the problem:
1) Open a port in RS485 mode
2) Receive data from remote (OK)
3) Transmit data to remote (OK)
4) Receive data from remote (Nothing received)
In RS485 mode, imx_uart_start_tx() calls imx_uart_stop_rx() and, when the
transmission is complete, imx_uart_stop_tx() calls imx_uart_start_rx().
Since the above commit imx_uart_stop_rx() now sets the loopback bit but
imx_uart_start_rx() does not clear it causing the hardware to remain in
loopback mode and not receive external data.
Fix this by moving the existing loopback disable code to a helper function
and calling it from imx_uart_start_rx() too.
Fixes: 79d0224f6bf2 ("tty: serial: imx: Handle RS485 DE signal active high")
Cc: stable@vger.kernel.org
Signed-off-by: Martin Fuzzey <martin.fuzzey@flowbird.group>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20230616104838.2729694-1-martin.fuzzey@flowbird.group
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel
============
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There are various text files in the Documentation/ subdirectory,
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Please read the Documentation/process/changes.rst file, as it contains the
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