From fbd83971f9429849dd3a105b663822d15b7b992b Mon Sep 17 00:00:00 2001 From: Guido Kiener Date: Wed, 18 Jul 2018 10:45:38 +0200 Subject: [PATCH] usb: usbtmc: Add ioctl for EOM bit add USBTMC_IOCTL_EOM_ENABLE to specify EOM bit for next write() call. Sets Bit 0 of field 'bmTransferAttributes' of DEV_DEP_MSG_OUT Bulk-OUT Header. Allows fine grained control over end of message handling on a per file descriptor basis. Reviewed-by: Steve Bayless Tested-by: Dave Penkler Signed-off-by: Dave Penkler Signed-off-by: Guido Kiener Signed-off-by: Greg Kroah-Hartman --- drivers/usb/class/usbtmc.c | 28 +++++++++++++++++++++++++++- include/uapi/linux/usb/tmc.h | 2 ++ 2 files changed, 29 insertions(+), 1 deletion(-) diff --git a/drivers/usb/class/usbtmc.c b/drivers/usb/class/usbtmc.c index 38fc7abdc00c..c77e0ac6260b 100644 --- a/drivers/usb/class/usbtmc.c +++ b/drivers/usb/class/usbtmc.c @@ -120,6 +120,7 @@ struct usbtmc_file_data { u32 timeout; u8 srq_byte; atomic_t srq_asserted; + u8 eom_val; }; /* Forward declarations */ @@ -157,6 +158,7 @@ static int usbtmc_open(struct inode *inode, struct file *filp) file_data->data = data; file_data->timeout = USBTMC_TIMEOUT; + file_data->eom_val = 1; INIT_LIST_HEAD(&file_data->file_elem); spin_lock_irq(&data->dev_lock); @@ -855,7 +857,7 @@ static ssize_t usbtmc_write(struct file *filp, const char __user *buf, buffer[8] = 0; } else { this_part = remaining; - buffer[8] = 1; + buffer[8] = file_data->eom_val; } /* Setup IO buffer for DEV_DEP_MSG_OUT message */ @@ -1277,6 +1279,25 @@ static int usbtmc_ioctl_set_timeout(struct usbtmc_file_data *file_data, return 0; } +/* + * enables/disables sending EOM on write + */ +static int usbtmc_ioctl_eom_enable(struct usbtmc_file_data *file_data, + void __user *arg) +{ + u8 eom_enable; + + if (copy_from_user(&eom_enable, arg, sizeof(eom_enable))) + return -EFAULT; + + if (eom_enable > 1) + return -EINVAL; + + file_data->eom_val = eom_enable; + + return 0; +} + static long usbtmc_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { struct usbtmc_file_data *file_data; @@ -1327,6 +1348,11 @@ static long usbtmc_ioctl(struct file *file, unsigned int cmd, unsigned long arg) (void __user *)arg); break; + case USBTMC_IOCTL_EOM_ENABLE: + retval = usbtmc_ioctl_eom_enable(file_data, + (void __user *)arg); + break; + case USBTMC488_IOCTL_GET_CAPS: retval = copy_to_user((void __user *)arg, &data->usb488_caps, diff --git a/include/uapi/linux/usb/tmc.h b/include/uapi/linux/usb/tmc.h index c61bad7150dd..e7317dfdd2ae 100644 --- a/include/uapi/linux/usb/tmc.h +++ b/include/uapi/linux/usb/tmc.h @@ -50,6 +50,8 @@ #define USBTMC_IOCTL_CLEAR_IN_HALT _IO(USBTMC_IOC_NR, 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 USBTMC488_IOCTL_GET_CAPS _IOR(USBTMC_IOC_NR, 17, unsigned char) #define USBTMC488_IOCTL_READ_STB _IOR(USBTMC_IOC_NR, 18, unsigned char) #define USBTMC488_IOCTL_REN_CONTROL _IOW(USBTMC_IOC_NR, 19, unsigned char)