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| author |   Razvan Stefanescu <razvan.stefanescu@microchip.com> | 2019-03-19 15:20:35 +0200 |
|---|---|---|
| committer |   Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-03-28 00:27:48 +0900 |
| commit | 69646d7a3689fbe1a65ae90397d22ac3f1b8d40f (patch) | |
| tree | a09a7229153b649687677d239afe775d72d5b17c /Documentation | |
| parent | tty/serial: atmel: Add is_half_duplex helper (diff) | |
| download | linux-dev-69646d7a3689fbe1a65ae90397d22ac3f1b8d40f.tar.xz linux-dev-69646d7a3689fbe1a65ae90397d22ac3f1b8d40f.zip | |
tty/serial: atmel: RS485 HD w/DMA: enable RX after TX is stopped
In half-duplex operation, RX should be started after TX completes.
If DMA is used, there is a case when the DMA transfer completes but the
TX FIFO is not emptied, so the RX cannot be restarted just yet.
Use a boolean variable to store this state and rearm TX interrupt mask
to be signaled again that the transfer finished. In interrupt transmit
handler this variable is used to start RX. A warning message is generated
if RX is activated before TX fifo is cleared.
Fixes: b389f173aaa1 ("tty/serial: atmel: RS485 half duplex w/DMA: enable
RX after TX is done")
Signed-off-by: Razvan Stefanescu <razvan.stefanescu@microchip.com>
Acked-by: Richard Genoud <richard.genoud@gmail.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'Documentation')
0 files changed, 0 insertions, 0 deletions