Commit ec412b92 authored by Andre Herms's avatar Andre Herms Committed by Greg Kroah-Hartman

USB: usbtmc: repeat usb_bulk_msg until whole message is transfered

usb_bulk_msg() transfers only bytes up to the maximum packet size.
It must be repeated by the usbtmc driver until all bytes of a TMC message
are transfered.

Without this patch, ETIMEDOUT is reported when writing TMC messages
larger than the maximum USB bulk size and the transfer remains incomplete.
The user will notice that the device hangs and must be reset by either closing
the application or pulling the plug.
Signed-off-by: default avatarAndre Herms <andre.herms@tec-venture.de>
Cc: stable <stable@kernel.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 7723de7e
......@@ -562,10 +562,16 @@ static ssize_t usbtmc_write(struct file *filp, const char __user *buf,
n_bytes = roundup(12 + this_part, 4);
memset(buffer + 12 + this_part, 0, n_bytes - (12 + this_part));
do {
retval = usb_bulk_msg(data->usb_dev,
usb_sndbulkpipe(data->usb_dev,
data->bulk_out),
buffer, n_bytes, &actual, USBTMC_TIMEOUT);
buffer, n_bytes,
&actual, USBTMC_TIMEOUT);
if (retval != 0)
break;
n_bytes -= actual;
} while (n_bytes);
data->bTag_last_write = data->bTag;
data->bTag++;
......
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