Commit 8409e96f authored by Guido Kiener's avatar Guido Kiener Committed by Greg Kroah-Hartman
Browse files

usb: usbtmc: add ioctl USBTMC_IOCTL_MSG_IN_ATTR 



add ioctl USBTMC_IOCTL_MSG_IN_ATTR that returns the specific
bmTransferAttributes field of the last DEV_DEP_MSG_IN Bulk-IN
header. This header is received by the read() function. The
meaning of the (u8) bitmap bmTransferAttributes is:

Bit 0 = EOM flag is set when the last transfer of a USBTMC
message is received.

Bit 1 = is set when the last byte is a termchar (e.g. '\n').
Note that this bit is always zero when the device does not support
the termchar feature or when termchar detection is not enabled
(see ioctl USBTMC_IOCTL_CONFIG_TERMCHAR).

Signed-off-by: default avatarGuido Kiener <guido.kiener@rohde-schwarz.com>
Reviewed-by: default avatarSteve Bayless <steve_bayless@keysight.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 739240a9

drivers/usb/class/usbtmc.c

+8 −0
Original line number Diff line number Diff line
@@ -131,6 +131,7 @@ struct usbtmc_file_data { 
	u8             srq_byte;

	atomic_t       srq_asserted;

	atomic_t       closing;

	u8             bmTransferAttributes; /* member of DEV_DEP_MSG_IN */



	u8             eom_val;

	u8             term_char;
@@ -1435,6 +1436,8 @@ static ssize_t usbtmc_read(struct file *filp, char __user *buf, 
				       (buffer[6] << 16) +

				       (buffer[7] << 24);



			file_data->bmTransferAttributes = buffer[8];



			if (n_characters > this_part) {

				dev_err(dev, "Device wants to return more data than requested: %u > %zu\n", n_characters, count);

				if (data->auto_abort)
@@ -2199,6 +2202,11 @@ static long usbtmc_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 
						  (__u32 __user *)arg);

		break;



	case USBTMC_IOCTL_MSG_IN_ATTR:

		retval = put_user(file_data->bmTransferAttributes,

				  (__u8 __user *)arg);

		break;



	case USBTMC_IOCTL_CANCEL_IO:

		retval = usbtmc_ioctl_cancel_io(file_data);

		break;

include/uapi/linux/usb/tmc.h

+2 −0
Original line number Diff line number Diff line
@@ -98,6 +98,8 @@ struct usbtmc_message { 
#define USBTMC488_IOCTL_TRIGGER		_IO(USBTMC_IOC_NR, 22)

#define USBTMC488_IOCTL_WAIT_SRQ	_IOW(USBTMC_IOC_NR, 23, __u32)



#define USBTMC_IOCTL_MSG_IN_ATTR	_IOR(USBTMC_IOC_NR, 24, __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)

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