Commit 12dcaeb7 authored by Guido Kiener's avatar Guido Kiener Committed by Greg Kroah-Hartman
Browse files

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: default avatarSteve Bayless <steve_bayless@keysight.com>
Tested-by: default avatarDave Penkler <dpenkler@gmail.com>
Signed-off-by: default avatarDave Penkler <dpenkler@gmail.com>
Signed-off-by: default avatarGuido Kiener <guido.kiener@rohde-schwarz.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent fbd83971

drivers/usb/class/usbtmc.c

+34 −2
Original line number Diff line number Diff line
@@ -121,6 +121,8 @@ struct usbtmc_file_data { 
	u8             srq_byte;

	atomic_t       srq_asserted;

	u8             eom_val;

	u8             term_char;

	bool           term_char_enabled;

};



/* Forward declarations */
@@ -157,7 +159,10 @@ static int usbtmc_open(struct inode *inode, struct file *filp) 
	mutex_lock(&data->io_mutex);

	file_data->data = data;



	/* copy default values from device settings */

	file_data->timeout = USBTMC_TIMEOUT;

	file_data->term_char = data->TermChar;

	file_data->term_char_enabled = data->TermCharEnabled;

	file_data->eom_val = 1;



	INIT_LIST_HEAD(&file_data->file_elem);
@@ -634,9 +639,9 @@ static int send_request_dev_dep_msg_in(struct usbtmc_file_data *file_data, 
	buffer[5] = transfer_size >> 8;

	buffer[6] = transfer_size >> 16;

	buffer[7] = transfer_size >> 24;

	buffer[8] = data->TermCharEnabled * 2;

	buffer[8] = file_data->term_char_enabled * 2;

	/* Use term character? */

	buffer[9] = data->TermChar;

	buffer[9] = file_data->term_char;

	buffer[10] = 0; /* Reserved */

	buffer[11] = 0; /* Reserved */
@@ -1298,6 +1303,28 @@ static int usbtmc_ioctl_eom_enable(struct usbtmc_file_data *file_data, 
	return 0;

}



/*

 * Configure termination character for read()

 */

static int usbtmc_ioctl_config_termc(struct usbtmc_file_data *file_data,

				void __user *arg)

{

	struct usbtmc_termchar termc;



	if (copy_from_user(&termc, arg, sizeof(termc)))

		return -EFAULT;



	if ((termc.term_char_enabled > 1) ||

		(termc.term_char_enabled &&

		!(file_data->data->capabilities.device_capabilities & 1)))

		return -EINVAL;



	file_data->term_char = termc.term_char;

	file_data->term_char_enabled = termc.term_char_enabled;



	return 0;

}



static long usbtmc_ioctl(struct file *file, unsigned int cmd, unsigned long arg)

{

	struct usbtmc_file_data *file_data;
@@ -1353,6 +1380,11 @@ static long usbtmc_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 
						 (void __user *)arg);

		break;



	case USBTMC_IOCTL_CONFIG_TERMCHAR:

		retval = usbtmc_ioctl_config_termc(file_data,

						   (void __user *)arg);

		break;



	case USBTMC488_IOCTL_GET_CAPS:

		retval = copy_to_user((void __user *)arg,

				&data->usb488_caps,

include/uapi/linux/usb/tmc.h

+6 −0
Original line number Diff line number Diff line
@@ -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)

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