diff options
Diffstat (limited to 'drivers/usb/serial/cp210x.c')
| -rw-r--r-- | drivers/usb/serial/cp210x.c | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/drivers/usb/serial/cp210x.c b/drivers/usb/serial/cp210x.c index f5143eedbc48..a90801ef0055 100644 --- a/drivers/usb/serial/cp210x.c +++ b/drivers/usb/serial/cp210x.c @@ -272,6 +272,8 @@ static struct usb_serial_driver cp210x_device = { .break_ctl = cp210x_break_ctl, .set_termios = cp210x_set_termios, .tx_empty = cp210x_tx_empty, + .throttle = usb_serial_generic_throttle, + .unthrottle = usb_serial_generic_unthrottle, .tiocmget = cp210x_tiocmget, .tiocmset = cp210x_tiocmset, .attach = cp210x_attach, @@ -915,6 +917,7 @@ static void cp210x_get_termios_port(struct usb_serial_port *port, u32 baud; u16 bits; u32 ctl_hs; + u32 flow_repl; cp210x_read_u32_reg(port, CP210X_GET_BAUDRATE, &baud); @@ -1015,6 +1018,22 @@ static void cp210x_get_termios_port(struct usb_serial_port *port, ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake); if (ctl_hs & CP210X_SERIAL_CTS_HANDSHAKE) { dev_dbg(dev, "%s - flow control = CRTSCTS\n", __func__); + /* + * When the port is closed, the CP210x hardware disables + * auto-RTS and RTS is deasserted but it leaves auto-CTS when + * in hardware flow control mode. When re-opening the port, if + * auto-CTS is enabled on the cp210x, then auto-RTS must be + * re-enabled in the driver. + */ + flow_repl = le32_to_cpu(flow_ctl.ulFlowReplace); + flow_repl &= ~CP210X_SERIAL_RTS_MASK; + flow_repl |= CP210X_SERIAL_RTS_SHIFT(CP210X_SERIAL_RTS_FLOW_CTL); + flow_ctl.ulFlowReplace = cpu_to_le32(flow_repl); + cp210x_write_reg_block(port, + CP210X_SET_FLOW, + &flow_ctl, + sizeof(flow_ctl)); + cflag |= CRTSCTS; } else { dev_dbg(dev, "%s - flow control = NONE\n", __func__); |