Commit 29779d89 authored by Dave Penkler's avatar Dave Penkler Committed by Greg Kroah-Hartman
Browse files

Add ioctl to retrieve USBTMC-USB488 capabilities 



This is a convenience function to obtain an instrument's
capabilities from its file descriptor without having to access sysfs
from the user program.

Signed-off-by: default avatarDave Penkler <dpenkler@gmail.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent eb6b92ec

drivers/usb/class/usbtmc.c

+12 −0
Original line number Diff line number Diff line
@@ -102,6 +102,9 @@ struct usbtmc_device_data { 
	u16            iin_wMaxPacketSize;

	atomic_t       srq_asserted;



	/* coalesced usb488_caps from usbtmc_dev_capabilities */

	__u8 usb488_caps;



	u8 rigol_quirk;



	/* attributes from the USB TMC spec for this device */
@@ -993,6 +996,7 @@ static int get_capabilities(struct usbtmc_device_data *data) 
	data->capabilities.device_capabilities = buffer[5];

	data->capabilities.usb488_interface_capabilities = buffer[14];

	data->capabilities.usb488_device_capabilities = buffer[15];

	data->usb488_caps = (buffer[14] & 0x07) | ((buffer[15] & 0x0f) << 4);

	rv = 0;



err_out:
@@ -1168,6 +1172,14 @@ static long usbtmc_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 
		retval = usbtmc_ioctl_abort_bulk_in(data);

		break;



	case USBTMC488_IOCTL_GET_CAPS:

		retval = copy_to_user((void __user *)arg,

				&data->usb488_caps,

				sizeof(data->usb488_caps));

		if (retval)

			retval = -EFAULT;

		break;



	case USBTMC488_IOCTL_READ_STB:

		retval = usbtmc488_ioctl_read_stb(data, (void __user *)arg);

		break;

include/uapi/linux/usb/tmc.h

+18 −3
Original line number Diff line number Diff line
@@ -2,12 +2,14 @@ 
 * Copyright (C) 2007 Stefan Kopp, Gechingen, Germany

 * Copyright (C) 2008 Novell, Inc.

 * Copyright (C) 2008 Greg Kroah-Hartman <gregkh@suse.de>

 * Copyright (C) 2015 Dave Penkler <dpenkler@gmail.com>

 *

 * This file holds USB constants defined by the USB Device Class

 * Definition for Test and Measurement devices published by the USB-IF.

 * and USB488 Subclass Definitions for Test and Measurement devices

 * published by the USB-IF.

 *

 * It also has the ioctl definitions for the usbtmc kernel driver that

 * userspace needs to know about.

 * It also has the ioctl and capability definitions for the

 * usbtmc kernel driver that userspace needs to know about.

 */



#ifndef __LINUX_USB_TMC_H
@@ -40,6 +42,19 @@ 
#define USBTMC_IOCTL_ABORT_BULK_IN	_IO(USBTMC_IOC_NR, 4)

#define USBTMC_IOCTL_CLEAR_OUT_HALT	_IO(USBTMC_IOC_NR, 6)

#define USBTMC_IOCTL_CLEAR_IN_HALT	_IO(USBTMC_IOC_NR, 7)

#define USBTMC488_IOCTL_GET_CAPS	_IOR(USBTMC_IOC_NR, 17, unsigned char)

#define USBTMC488_IOCTL_READ_STB	_IOR(USBTMC_IOC_NR, 18, unsigned char)



/* Driver encoded usb488 capabilities */

#define USBTMC488_CAPABILITY_TRIGGER         1

#define USBTMC488_CAPABILITY_SIMPLE          2

#define USBTMC488_CAPABILITY_REN_CONTROL     2

#define USBTMC488_CAPABILITY_GOTO_LOCAL      2

#define USBTMC488_CAPABILITY_LOCAL_LOCKOUT   2

#define USBTMC488_CAPABILITY_488_DOT_2       4

#define USBTMC488_CAPABILITY_DT1             16

#define USBTMC488_CAPABILITY_RL1             32

#define USBTMC488_CAPABILITY_SR1             64

#define USBTMC488_CAPABILITY_FULL_SCPI       128



#endif