[PATCH v4 3/3] usb: misc: usbsevseg: update to use usb_control_msg_send()

[Anant Thazhemadam]

The newer usb_control_msg_{send|recv}() API ensures that a short read is 
treated as an error, data can be used off the stack, and raw usb pipes 
need not be created in the calling functions.
For this reason, instances of usb_control_msg() have been replaced with
usb_control_msg_send() appropriately.

Signed-off-by: Anant Thazhemadam <anant.thazhemadam@xxxxxxxxx>
---
 drivers/usb/misc/usbsevseg.c | 60 ++++++++++--------------------------
 1 file changed, 17 insertions(+), 43 deletions(-)

diff --git a/drivers/usb/misc/usbsevseg.c b/drivers/usb/misc/usbsevseg.c
index 551074f5b7ad..4bc816bb09bb 100644
--- a/drivers/usb/misc/usbsevseg.c
+++ b/drivers/usb/misc/usbsevseg.c
@@ -74,15 +74,10 @@ static void update_display_powered(struct usb_sevsegdev *mydev)
 	if (mydev->shadow_power != 1)
 		return;
 
-	rc = usb_control_msg(mydev->udev,
-			usb_sndctrlpipe(mydev->udev, 0),
-			0x12,
-			0x48,
-			(80 * 0x100) + 10, /*  (power mode) */
-			(0x00 * 0x100) + (mydev->powered ? 1 : 0),
-			NULL,
-			0,
-			2000);
+	rc = usb_control_msg_send(mydev->udev, 0, 0x12, 0x48,
+				  (80 * 0x100) + 10, /*  (power mode) */
+				  (0x00 * 0x100) + (mydev->powered ? 1 : 0),
+				  NULL, 0, 2000, GFP_KERNEL);
 	if (rc < 0)
 		dev_dbg(&mydev->udev->dev, "power retval = %d\n", rc);
 
@@ -99,15 +94,10 @@ static void update_display_mode(struct usb_sevsegdev *mydev)
 	if(mydev->shadow_power != 1)
 		return;
 
-	rc = usb_control_msg(mydev->udev,
-			usb_sndctrlpipe(mydev->udev, 0),
-			0x12,
-			0x48,
-			(82 * 0x100) + 10, /* (set mode) */
-			(mydev->mode_msb * 0x100) + mydev->mode_lsb,
-			NULL,
-			0,
-			2000);
+	rc = usb_control_msg_send(mydev->udev, 0, 0x12, 0x48,
+				  (82 * 0x100) + 10, /* (set mode) */
+				  (mydev->mode_msb * 0x100) + mydev->mode_lsb,
+				  NULL, 0, 2000, GFP_NOIO);
 
 	if (rc < 0)
 		dev_dbg(&mydev->udev->dev, "mode retval = %d\n", rc);
@@ -117,48 +107,32 @@ static void update_display_visual(struct usb_sevsegdev *mydev, gfp_t mf)
 {
 	int rc;
 	int i;
-	unsigned char *buffer;
+	unsigned char buffer[MAXLEN] = {0};
 	u8 decimals = 0;
 
 	if(mydev->shadow_power != 1)
 		return;
 
-	buffer = kzalloc(MAXLEN, mf);
-	if (!buffer)
-		return;
-
 	/* The device is right to left, where as you write left to right */
 	for (i = 0; i < mydev->textlength; i++)
 		buffer[i] = mydev->text[mydev->textlength-1-i];
 
-	rc = usb_control_msg(mydev->udev,
-			usb_sndctrlpipe(mydev->udev, 0),
-			0x12,
-			0x48,
-			(85 * 0x100) + 10, /* (write text) */
-			(0 * 0x100) + mydev->textmode, /* mode  */
-			buffer,
-			mydev->textlength,
-			2000);
+	rc = usb_control_msg_send(mydev->udev, 0, 0x12, 0x48,
+				  (85 * 0x100) + 10, /* (write text) */
+				  (0 * 0x100) + mydev->textmode, /* mode  */
+				  &buffer, mydev->textlength, 2000, mf);
 
 	if (rc < 0)
 		dev_dbg(&mydev->udev->dev, "write retval = %d\n", rc);
 
-	kfree(buffer);
-
 	/* The device is right to left, where as you write left to right */
 	for (i = 0; i < sizeof(mydev->decimals); i++)
 		decimals |= mydev->decimals[i] << i;
 
-	rc = usb_control_msg(mydev->udev,
-			usb_sndctrlpipe(mydev->udev, 0),
-			0x12,
-			0x48,
-			(86 * 0x100) + 10, /* (set decimal) */
-			(0 * 0x100) + decimals, /* decimals */
-			NULL,
-			0,
-			2000);
+	rc = usb_control_msg_send(mydev->udev, 0, 0x12, 0x48,
+				  (86 * 0x100) + 10, /* (set decimal) */
+				  (0 * 0x100) + decimals, /* decimals */
+				  NULL, 0, 2000, mf);
 
 	if (rc < 0)
 		dev_dbg(&mydev->udev->dev, "decimal retval = %d\n", rc);
-- 
2.25.1