[PATCH v2 5/6] USB: serial: keyspan_pda: use usb_control_msg_recv()

[Himadri Pandya]

Use the wrapper function usb_control_msg_recv() that accepts stack
variables and remove dma buffers from callers of usb_control_msg().

Signed-off-by: Himadri Pandya <himadrispandya@xxxxxxxxx>
---
Changes in v2:
 - Rebase the patch on top of recent changes
 - Drop unrelated style changes
---
 drivers/usb/serial/keyspan_pda.c | 70 ++++++++++++++------------------
 1 file changed, 31 insertions(+), 39 deletions(-)

diff --git a/drivers/usb/serial/keyspan_pda.c b/drivers/usb/serial/keyspan_pda.c
index 39b0f5f344c2..831dc5f42dea 100644
--- a/drivers/usb/serial/keyspan_pda.c
+++ b/drivers/usb/serial/keyspan_pda.c
@@ -77,35 +77,28 @@ static int keyspan_pda_get_write_room(struct keyspan_pda_private *priv)
 {
 	struct usb_serial_port *port = priv->port;
 	struct usb_serial *serial = port->serial;
-	u8 *room;
+	u8 room;
 	int rc;
 
-	room = kmalloc(1, GFP_KERNEL);
-	if (!room)
-		return -ENOMEM;
-
-	rc = usb_control_msg(serial->dev,
-			     usb_rcvctrlpipe(serial->dev, 0),
-			     6, /* write_room */
-			     USB_TYPE_VENDOR | USB_RECIP_INTERFACE
-			     | USB_DIR_IN,
-			     0, /* value: 0 means "remaining room" */
-			     0, /* index */
-			     room,
-			     1,
-			     2000);
-	if (rc != 1) {
-		if (rc >= 0)
-			rc = -EIO;
+	rc = usb_control_msg_recv(serial->dev,
+				  0,
+				  6, /* write_room */
+				  USB_TYPE_VENDOR | USB_RECIP_INTERFACE
+				  | USB_DIR_IN,
+				  0, /* value: 0 means "remaining room" */
+				  0, /* index */
+				  &room,
+				  1,
+				  2000,
+				  GFP_KERNEL);
+	if (rc) {
 		dev_dbg(&port->dev, "roomquery failed: %d\n", rc);
-		goto out_free;
+		goto out;
 	}
 
-	dev_dbg(&port->dev, "roomquery says %d\n", *room);
-	rc = *room;
-out_free:
-	kfree(room);
-
+	dev_dbg(&port->dev, "roomquery says %d\n", room);
+	rc = room;
+out:
 	return rc;
 }
 
@@ -381,22 +374,21 @@ static int keyspan_pda_get_modem_info(struct usb_serial *serial,
 				      unsigned char *value)
 {
 	int rc;
-	u8 *data;
-
-	data = kmalloc(1, GFP_KERNEL);
-	if (!data)
-		return -ENOMEM;
-
-	rc = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
-			     3, /* get pins */
-			     USB_TYPE_VENDOR|USB_RECIP_INTERFACE|USB_DIR_IN,
-			     0, 0, data, 1, 2000);
-	if (rc == 1)
-		*value = *data;
-	else if (rc >= 0)
-		rc = -EIO;
+	u8 data;
+
+	rc = usb_control_msg_recv(serial->dev, 0,
+				  3, /* get pins */
+				  USB_TYPE_VENDOR | USB_RECIP_INTERFACE |
+				  USB_DIR_IN,
+				  0,
+				  0,
+				  &data,
+				  1,
+				  2000,
+				  GFP_KERNEL);
+	if (rc == 0)
+		*value = data;
 
-	kfree(data);
 	return rc;
 }
 
-- 
2.17.1