Add tx_empty() function for F81232 & F81534A series.
Signed-off-by: Ji-Ze Hong (Peter Hong) <hpeter+linux_kernel@xxxxxxxxx>
---
drivers/usb/serial/f81232.c | 19 +++++++++++++++++++
1 file changed, 19 insertions(+)
diff --git a/drivers/usb/serial/f81232.c b/drivers/usb/serial/f81232.c
index e9470fb0d691..7d1ec8f9d168 100644
--- a/drivers/usb/serial/f81232.c
+++ b/drivers/usb/serial/f81232.c
@@ -850,6 +850,24 @@ static void f81232_dtr_rts(struct usb_serial_port *port, int on)
f81232_set_mctrl(port, 0, TIOCM_DTR | TIOCM_RTS);
}
+static bool f81232_tx_empty(struct usb_serial_port *port)
+{
+ int status;
+ u8 tmp;
+ u8 both_empty = UART_LSR_TEMT | UART_LSR_THRE;
+
+ status = f81232_get_register(port, LINE_STATUS_REGISTER, &tmp);
+ if (status) {
+ dev_err(&port->dev, "get LSR status failed: %d\n", status);
+ return false;
+ }
+
+ if ((tmp & both_empty) != both_empty)
+ return false;
+
+ return true;
+}
+
static int f81232_carrier_raised(struct usb_serial_port *port)
{
u8 msr;
@@ -1279,6 +1297,7 @@ static struct usb_serial_driver f81232_device = {
.tiocmget = f81232_tiocmget,
.tiocmset = f81232_tiocmset,
.tiocmiwait = usb_serial_generic_tiocmiwait,
+ .tx_empty = f81232_tx_empty,
.process_read_urb = f81232_read_urb_proxy,
.read_int_callback = f81232_read_int_callback,
.port_probe = f81232_port_probe,
--
2.7.4
