diff options
| author | Axel Haslam <ahaslam@baylibre.com> | 2016-05-31 14:36:12 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@google.com> | 2016-05-31 17:18:18 -0700 |
| commit | 2b3b87f056b276b688cb0429faf682cac33dbf7b (patch) | |
| tree | 87195edc1814cc9c28ae3d3c8194f305e999d1eb /drivers/staging/greybus/uart.c | |
| parent | a8bc00fb88037e0107a0682478f47396a073be5c (diff) | |
greybus: uart: Implement flush_buffer
Data may be held pening in the hardware because of flow
control mechanisms. When the port is closed, we need to flush
all data that was not sent.
For this, use the greybus message GB_UART_TYPE_FLUSH_FIFOS
which will flush all data queued on the module but not
yet sent on the data line.
Suggested-by: Johan Hovold <johan@hovoldconsulting.com>
Signed-off-by: Axel Haslam <ahaslam@baylibre.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Diffstat (limited to 'drivers/staging/greybus/uart.c')
| -rw-r--r-- | drivers/staging/greybus/uart.c | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/drivers/staging/greybus/uart.c b/drivers/staging/greybus/uart.c index 14b3e9d06e9c..7dc9f9b873b1 100644 --- a/drivers/staging/greybus/uart.c +++ b/drivers/staging/greybus/uart.c @@ -317,6 +317,14 @@ static int send_break(struct gb_tty *gb_tty, u8 state) &request, sizeof(request), NULL, 0); } +static int gb_uart_flush(struct gb_tty *gb_tty, u8 flags) +{ + struct gb_uart_serial_flush_request request; + + request.flags = flags; + return gb_operation_sync(gb_tty->connection, GB_UART_TYPE_FLUSH_FIFOS, + &request, sizeof(request), NULL, 0); +} static struct gb_tty *get_gb_by_minor(unsigned minor) { @@ -745,6 +753,7 @@ static void gb_tty_port_shutdown(struct tty_port *port) { struct gb_tty *gb_tty; unsigned long flags; + int ret; gb_tty = container_of(port, struct gb_tty, port); @@ -756,6 +765,12 @@ static void gb_tty_port_shutdown(struct tty_port *port) kfifo_reset_out(&gb_tty->write_fifo); spin_unlock_irqrestore(&gb_tty->write_lock, flags); + ret = gb_uart_flush(gb_tty, GB_SERIAL_FLAG_FLUSH_TRANSMITTER); + if (ret) { + dev_err(&gb_tty->gbphy_dev->dev, + "error flushing transmitter: %d\n", ret); + } + gb_tty->close_pending = false; } |