diff options
| -rw-r--r-- | drivers/usb/serial/cp210x.c | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/drivers/usb/serial/cp210x.c b/drivers/usb/serial/cp210x.c index 66a6ac50a4cd..b98454fe08ea 100644 --- a/drivers/usb/serial/cp210x.c +++ b/drivers/usb/serial/cp210x.c @@ -258,6 +258,7 @@ struct cp210x_serial_private { speed_t max_speed; bool use_actual_rate; bool no_flow_control; + bool no_event_mode; }; enum cp210x_event_state { @@ -1113,12 +1114,16 @@ static void cp210x_change_speed(struct tty_struct *tty, static void cp210x_enable_event_mode(struct usb_serial_port *port) { + struct cp210x_serial_private *priv = usb_get_serial_data(port->serial); struct cp210x_port_private *port_priv = usb_get_serial_port_data(port); int ret; if (port_priv->event_mode) return; + if (priv->no_event_mode) + return; + port_priv->event_state = ES_DATA; port_priv->event_mode = true; @@ -2074,6 +2079,33 @@ static void cp210x_init_max_speed(struct usb_serial *serial) priv->use_actual_rate = use_actual_rate; } +static void cp2102_determine_quirks(struct usb_serial *serial) +{ + struct cp210x_serial_private *priv = usb_get_serial_data(serial); + u8 *buf; + int ret; + + buf = kmalloc(2, GFP_KERNEL); + if (!buf) + return; + /* + * Some (possibly counterfeit) CP2102 do not support event-insertion + * mode and respond differently to malformed vendor requests. + * Specifically, they return one instead of two bytes when sent a + * two-byte part-number request. + */ + ret = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0), + CP210X_VENDOR_SPECIFIC, REQTYPE_DEVICE_TO_HOST, + CP210X_GET_PARTNUM, 0, buf, 2, USB_CTRL_GET_TIMEOUT); + if (ret == 1) { + dev_dbg(&serial->interface->dev, + "device does not support event-insertion mode\n"); + priv->no_event_mode = true; + } + + kfree(buf); +} + static int cp210x_get_fw_version(struct usb_serial *serial, u16 value) { struct cp210x_serial_private *priv = usb_get_serial_data(serial); @@ -2109,6 +2141,9 @@ static void cp210x_determine_type(struct usb_serial *serial) } switch (priv->partnum) { + case CP210X_PARTNUM_CP2102: + cp2102_determine_quirks(serial); + break; case CP210X_PARTNUM_CP2105: case CP210X_PARTNUM_CP2108: cp210x_get_fw_version(serial, CP210X_GET_FW_VER); |