On Sun, Nov 29, 2015 at 01:35:51PM +0100, Dave Penkler wrote:
> 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: Dave Penkler <dpenkler@xxxxxxxxx>
> ---
> drivers/usb/class/usbtmc.c | 12 ++++++++++++
> include/uapi/linux/usb/tmc.h | 21 ++++++++++++++++++---
> 2 files changed, 30 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/usb/class/usbtmc.c b/drivers/usb/class/usbtmc.c
> index 3b85ef5..3a3264c 100644
> --- a/drivers/usb/class/usbtmc.c
> +++ b/drivers/usb/class/usbtmc.c
> @@ -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 */
> @@ -992,6 +995,7 @@ 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:
> @@ -1167,6 +1171,14 @@ 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, arg);
> break;
> diff --git a/include/uapi/linux/usb/tmc.h b/include/uapi/linux/usb/tmc.h
> index 7e5ced8..1dc3af1 100644
> --- a/include/uapi/linux/usb/tmc.h
> +++ b/include/uapi/linux/usb/tmc.h
> @@ -2,12 +2,14 @@
> * Copyright (C) 2007 Stefan Kopp, Gechingen, Germany
> * Copyright (C) 2008 Novell, Inc.
> * Copyright (C) 2008 Greg Kroah-Hartman <gregkh@xxxxxxx>
> + * Copyright (C) 2015 Dave Penkler <dpenkler@xxxxxxxxx>
> *
> * 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 _IO(USBTMC_IOC_NR, 17)
Shouldn't there be a data structure mentioned here that gets passed back
to userspace? And are you sure the direction is correct as well?
thanks,
greg k-h
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
