From 4143d178e7b39c00d5277040c69a1522c4d98871 Mon Sep 17 00:00:00 2001 From: Steve Holland Date: Thu, 18 Jun 2009 17:37:49 -0500 Subject: [PATCH] USB: usbtmc: correct termination condition for reads. Follow T&M convention of obeying EOM flag. Avoid exception cases where instrument response size matches a buffer size. Signed-off-by: Steve Holland Signed-off-by: Greg Kroah-Hartman --- drivers/usb/class/usbtmc.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/usb/class/usbtmc.c b/drivers/usb/class/usbtmc.c index 91d3a94eeaa0..6395f22a58e1 100644 --- a/drivers/usb/class/usbtmc.c +++ b/drivers/usb/class/usbtmc.c @@ -485,7 +485,8 @@ static ssize_t usbtmc_read(struct file *filp, char __user *buf, } done += n_characters; - if (n_characters < USBTMC_SIZE_IOBUFFER) + /* Terminate if end-of-message bit recieved from device */ + if ((buffer[8] & 0x01) && (actual >= n_characters + 12)) remaining = 0; else remaining -= n_characters; -- 2.20.1