diff options
Diffstat (limited to 'drivers/usb/class/usbtmc.c')
| -rw-r--r-- | drivers/usb/class/usbtmc.c | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/drivers/usb/class/usbtmc.c b/drivers/usb/class/usbtmc.c index 36d740c4c6fb..38fc7abdc00c 100644 --- a/drivers/usb/class/usbtmc.c +++ b/drivers/usb/class/usbtmc.c @@ -558,6 +558,51 @@ static int usbtmc488_ioctl_simple(struct usbtmc_device_data *data, } /* + * Sends a TRIGGER Bulk-OUT command message + * See the USBTMC-USB488 specification, Table 2. + * + * Also updates bTag_last_write. + */ +static int usbtmc488_ioctl_trigger(struct usbtmc_file_data *file_data) +{ + struct usbtmc_device_data *data = file_data->data; + int retval; + u8 *buffer; + int actual; + + buffer = kzalloc(USBTMC_HEADER_SIZE, GFP_KERNEL); + if (!buffer) + return -ENOMEM; + + buffer[0] = 128; + buffer[1] = data->bTag; + buffer[2] = ~data->bTag; + + retval = usb_bulk_msg(data->usb_dev, + usb_sndbulkpipe(data->usb_dev, + data->bulk_out), + buffer, USBTMC_HEADER_SIZE, + &actual, file_data->timeout); + + /* Store bTag (in case we need to abort) */ + data->bTag_last_write = data->bTag; + + /* Increment bTag -- and increment again if zero */ + data->bTag++; + if (!data->bTag) + data->bTag++; + + kfree(buffer); + if (retval < 0) { + dev_err(&data->intf->dev, "%s returned %d\n", + __func__, retval); + return retval; + } + + return 0; +} + +/* * Sends a REQUEST_DEV_DEP_MSG_IN message on the Bulk-OUT endpoint. * @transfer_size: number of bytes to request from the device. * @@ -1309,6 +1354,10 @@ static long usbtmc_ioctl(struct file *file, unsigned int cmd, unsigned long arg) retval = usbtmc488_ioctl_simple(data, (void __user *)arg, USBTMC488_REQUEST_LOCAL_LOCKOUT); break; + + case USBTMC488_IOCTL_TRIGGER: + retval = usbtmc488_ioctl_trigger(file_data); + break; } skip_io_on_zombie: |