This new ioctl reads the status byte (STB) from the device and returns
the STB unmodified to the application. The srq_asserted bit is not taken
into account and not changed.
This ioctl is useful to support non USBTMC-488 compliant devices.
Signed-off-by: Dave Penkler <dpenkler@xxxxxxxxx>
Reviewed-by: Guido Kiener <guido.kiener@xxxxxxxxxxxxxxxxx>
Tested-by: Jian-Wei Wu <jian-wei_wu@xxxxxxxxxxxx>
---
drivers/usb/class/usbtmc.c | 6 ++++++
include/uapi/linux/usb/tmc.h | 2 ++
2 files changed, 8 insertions(+)
diff --git a/drivers/usb/class/usbtmc.c b/drivers/usb/class/usbtmc.c
index 189f06dcb7d3..8918e2182eca 100644
--- a/drivers/usb/class/usbtmc.c
+++ b/drivers/usb/class/usbtmc.c
@@ -2149,6 +2149,12 @@ static long usbtmc_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
file_data->auto_abort = !!tmp_byte;
break;
+ case USBTMC_IOCTL_GET_STB:
+ retval = usbtmc_get_stb(file_data, &tmp_byte);
+ if (retval > 0)
+ retval = put_user(tmp_byte, (__u8 __user *)arg);
+ break;
+
case USBTMC_IOCTL_CANCEL_IO:
retval = usbtmc_ioctl_cancel_io(file_data);
break;
diff --git a/include/uapi/linux/usb/tmc.h b/include/uapi/linux/usb/tmc.h
index fdd4d88a7b95..1e7878fe591f 100644
--- a/include/uapi/linux/usb/tmc.h
+++ b/include/uapi/linux/usb/tmc.h
@@ -102,6 +102,8 @@ struct usbtmc_message {
#define USBTMC_IOCTL_MSG_IN_ATTR _IOR(USBTMC_IOC_NR, 24, __u8)
#define USBTMC_IOCTL_AUTO_ABORT _IOW(USBTMC_IOC_NR, 25, __u8)
+#define USBTMC_IOCTL_GET_STB _IOR(USBTMC_IOC_NR, 26, __u8)
+
/* Cancel and cleanup asynchronous calls */
#define USBTMC_IOCTL_CANCEL_IO _IO(USBTMC_IOC_NR, 35)
#define USBTMC_IOCTL_CLEANUP_IO _IO(USBTMC_IOC_NR, 36)
--
2.29.2
