USB: usbtmc: Fix short reads in usbtmc_read()

The header size should not be included in the number of bytes requested of the
instrument

Signed-off-by: Steve Holland <sdh4@iastate.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 4 insertions, 4 deletions

diff --git a/drivers/usb/class/usbtmc.c b/drivers/usb/class/usbtmc.c
index 40ef4da786d8..f2fde7cd6109 100644
--- a/drivers/usb/class/usbtmc.c
+++ b/drivers/usb/class/usbtmc.c
@@ -407,10 +407,10 @@ static ssize_t usbtmc_read(struct file *filp, char __user *buf,
                 buffer[1] = data->bTag;
                 buffer[2] = ~(data->bTag);
                 buffer[3] = 0; /* Reserved */
-                buffer[4] = (this_part - 12 - 3) & 255;
-                buffer[5] = ((this_part - 12 - 3) >> 8) & 255;
-                buffer[6] = ((this_part - 12 - 3) >> 16) & 255;
-                buffer[7] = ((this_part - 12 - 3) >> 24) & 255;
+                buffer[4] = (this_part) & 255;
+                buffer[5] = ((this_part) >> 8) & 255;
+                buffer[6] = ((this_part) >> 16) & 255;
+                buffer[7] = ((this_part) >> 24) & 255;
                 buffer[8] = data->TermCharEnabled * 2;
                 /* Use term character? */
                 buffer[9] = data->TermChar;