usb: usbtmc: Add ioctl for termination character

add USBTMC_IOCTL_CONFIG_TERMCHAR to control TermChar handling
for next read(). Controls field 'TermChar' and Bit 1 of field
'bmTransferAttributes' of REQUEST_DEV_DEP_MSG_IN BULK-OUT header.

Allows enabling/disabling of terminating a read on reception of
term_char individually for each read request.

Reviewed-by: Steve Bayless <steve_bayless@keysight.com>
Tested-by: Dave Penkler <dpenkler@gmail.com>
Signed-off-by: Dave Penkler <dpenkler@gmail.com>
Signed-off-by: Guido Kiener <guido.kiener@rohde-schwarz.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 6 insertions, 0 deletions

diff --git a/include/uapi/linux/usb/tmc.h b/include/uapi/linux/usb/tmc.h
index e7317dfdd2ae..729af2f861a4 100644
--- a/include/uapi/linux/usb/tmc.h
+++ b/include/uapi/linux/usb/tmc.h
@@ -40,6 +40,11 @@
 #define USBTMC488_REQUEST_GOTO_LOCAL                    161
 #define USBTMC488_REQUEST_LOCAL_LOCKOUT                 162
 
+struct usbtmc_termchar {
+        __u8 term_char;
+        __u8 term_char_enabled;
+} __attribute__ ((packed));
+
 /* Request values for USBTMC driver's ioctl entry point */
 #define USBTMC_IOC_NR                   91
 #define USBTMC_IOCTL_INDICATOR_PULSE    _IO(USBTMC_IOC_NR, 1)
@@ -51,6 +56,7 @@
 #define USBTMC_IOCTL_GET_TIMEOUT        _IOR(USBTMC_IOC_NR, 9, __u32)
 #define USBTMC_IOCTL_SET_TIMEOUT        _IOW(USBTMC_IOC_NR, 10, __u32)
 #define USBTMC_IOCTL_EOM_ENABLE         _IOW(USBTMC_IOC_NR, 11, __u8)
+#define USBTMC_IOCTL_CONFIG_TERMCHAR    _IOW(USBTMC_IOC_NR, 12, struct usbtmc_termchar)
 
 #define USBTMC488_IOCTL_GET_CAPS        _IOR(USBTMC_IOC_NR, 17, unsigned char)
 #define USBTMC488_IOCTL_READ_STB        _IOR(USBTMC_IOC_NR, 18, unsigned char)