USB: usbtmc: Change magic number to constant
These patches implement a modification of the USBTMC
protocol to allow operation with Rigol equipment. Cosmetic change to show
that 12 is the USBTMC header size.
Signed-off-by: Alexandre Peixoto Ferreira <alexandref75@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/usb/class/usbtmc.c b/drivers/usb/class/usbtmc.c
index 8ebd06b..609dbc2 100644
--- a/drivers/usb/class/usbtmc.c
+++ b/drivers/usb/class/usbtmc.c
@@ -640,8 +640,8 @@
done = 0;
while (remaining > 0) {
- if (remaining > USBTMC_SIZE_IOBUFFER - 12) {
- this_part = USBTMC_SIZE_IOBUFFER - 12;
+ if (remaining > USBTMC_SIZE_IOBUFFER - USBTMC_HEADER_SIZE) {
+ this_part = USBTMC_SIZE_IOBUFFER - USBTMC_HEADER_SIZE;
buffer[8] = 0;
} else {
this_part = remaining;
@@ -662,13 +662,13 @@
buffer[10] = 0; /* Reserved */
buffer[11] = 0; /* Reserved */
- if (copy_from_user(&buffer[12], buf + done, this_part)) {
+ if (copy_from_user(&buffer[USBTMC_HEADER_SIZE], buf + done, this_part)) {
retval = -EFAULT;
goto exit;
}
- n_bytes = roundup(12 + this_part, 4);
- memset(buffer + 12 + this_part, 0, n_bytes - (12 + this_part));
+ n_bytes = roundup(USBTMC_HEADER_SIZE + this_part, 4);
+ memset(buffer + USBTMC_HEADER_SIZE + this_part, 0, n_bytes - (USBTMC_HEADER_SIZE + this_part));
do {
retval = usb_bulk_msg(data->usb_dev,