USB: serial: metro-usb: get data from device in Uni-Directional mode.

We should send special control command to tell device start or stop
transmitting a data.

In Bi-Directional mode that cmd`s are not required.

Signed-off-by: Aleksey Babahin <tamerlan311@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 53 insertions, 0 deletions

diff --git a/drivers/usb/serial/metro-usb.c b/drivers/usb/serial/metro-usb.c
index 92b6f85ab4b9..2df22176515b 100644
--- a/drivers/usb/serial/metro-usb.c
+++ b/drivers/usb/serial/metro-usb.c
@@ -56,6 +56,47 @@ MODULE_DEVICE_TABLE(usb, id_table);
 /* Input parameter constants. */
 static bool debug;
 
+/* UNI-Directional mode commands for device configure */
+#define UNI_CMD_OPEN    0x80
+#define UNI_CMD_CLOSE   0xFF
+
+inline int metrousb_is_unidirectional_mode(struct usb_serial_port *port)
+{
+        __u16 product_id = le16_to_cpu(
+                port->serial->dev->descriptor.idProduct);
+
+        return product_id == FOCUS_PRODUCT_ID_UNI;
+}
+
+static int metrousb_send_unidirectional_cmd(u8 cmd, struct usb_serial_port *port)
+{
+        int ret;
+        int actual_len;
+        u8 *buffer_cmd = NULL;
+
+        if (!metrousb_is_unidirectional_mode(port))
+                return 0;
+
+        buffer_cmd = kzalloc(sizeof(cmd), GFP_KERNEL);
+        if (!buffer_cmd)
+                return -ENOMEM;
+
+        *buffer_cmd = cmd;
+
+        ret = usb_interrupt_msg(port->serial->dev,
+                usb_sndintpipe(port->serial->dev, port->interrupt_out_endpointAddress),
+                buffer_cmd, sizeof(cmd),
+                &actual_len, USB_CTRL_SET_TIMEOUT);
+
+        kfree(buffer_cmd);
+
+        if (ret < 0)
+                return ret;
+        else if (actual_len != sizeof(cmd))
+                return -EIO;
+        return 0;
+}
+
 static void metrousb_read_int_callback(struct urb *urb)
 {
         struct usb_serial_port *port = urb->context;
@@ -154,6 +195,9 @@ static void metrousb_cleanup(struct usb_serial_port *port)
                         usb_unlink_urb(port->interrupt_in_urb);
                         usb_kill_urb(port->interrupt_in_urb);
                 }
+
+                /* Send deactivate cmd to device */
+                metrousb_send_unidirectional_cmd(UNI_CMD_CLOSE, port);
         }
 }
 
@@ -205,6 +249,15 @@ static int metrousb_open(struct tty_struct *tty, struct usb_serial_port *port)
                 goto exit;
         }
 
+        /* Send activate cmd to device */
+        result = metrousb_send_unidirectional_cmd(UNI_CMD_OPEN, port);
+        if (result) {
+                dev_err(&port->dev,
+                        "%s - failed to configure device for port number=%d, error code=%d\n",
+                        __func__, port->number, result);
+                goto exit;
+        }
+
         dev_dbg(&port->dev, "%s - port open\n", __func__);
 exit:
         return result;