From e013477bc20763e28d95d74e5ca97411194984ec Mon Sep 17 00:00:00 2001 From: Guido Kiener Date: Wed, 12 Sep 2018 10:51:07 +0200 Subject: usb: usbtmc: Add ioctl USBTMC_IOCTL_API_VERSION Add ioctl USBTMC_IOCTL_API_VERSION to get current API version of usbtmc driver. This is to allow an instrument library to determine whether the driver API is compatible with the implementation. The API may change in future versions. Therefore the macro USBTMC_API_VERSION should be incremented when changing tmc.h with new flags, ioctls or when changing a significant behavior of the driver. Signed-off-by: Guido Kiener Reviewed-by: Steve Bayless Signed-off-by: Greg Kroah-Hartman --- drivers/usb/class/usbtmc.c | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'drivers/usb/class') diff --git a/drivers/usb/class/usbtmc.c b/drivers/usb/class/usbtmc.c index 964c8e87dacb..72867a97ec00 100644 --- a/drivers/usb/class/usbtmc.c +++ b/drivers/usb/class/usbtmc.c @@ -22,6 +22,10 @@ #include #include +/* Increment API VERSION when changing tmc.h with new flags or ioctls + * or when changing a significant behavior of the driver. + */ +#define USBTMC_API_VERSION (2) #define USBTMC_HEADER_SIZE 12 #define USBTMC_MINOR_BASE 176 @@ -2179,6 +2183,11 @@ static long usbtmc_ioctl(struct file *file, unsigned int cmd, unsigned long arg) (void __user *)arg); break; + case USBTMC_IOCTL_API_VERSION: + retval = put_user(USBTMC_API_VERSION, + (__u32 __user *)arg); + break; + case USBTMC488_IOCTL_GET_CAPS: retval = copy_to_user((void __user *)arg, &data->usb488_caps, -- cgit v1.2.3