Add ioctls to enable and disable local controls on an instrument

These ioctls provide support for the USBTMC-USB488 control requests
for REN_CONTROL, GO_TO_LOCAL and LOCAL_LOCKOUT

Signed-off-by: Dave Penkler <dpenkler@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/class/usbtmc.c b/drivers/usb/class/usbtmc.c
index 6edb21ca9989fff06211015a2db413e40dd0ca0a..419c72e1046469d8767df8debe663f029fd7b9af 100644 (file)
--- a/drivers/usb/class/usbtmc.c
+++ b/drivers/usb/class/usbtmc.c
@@ -474,6 +474,61 @@ static int usbtmc488_ioctl_read_stb(struct usbtmc_device_data *data,
        return rv;
 }
 
+static int usbtmc488_ioctl_simple(struct usbtmc_device_data *data,
+                               void __user *arg, unsigned int cmd)
+{
+       struct device *dev = &data->intf->dev;
+       __u8 val;
+       u8 *buffer;
+       u16 wValue;
+       int rv;
+
+       if (!(data->usb488_caps & USBTMC488_CAPABILITY_SIMPLE))
+               return -EINVAL;
+
+       buffer = kmalloc(8, GFP_KERNEL);
+       if (!buffer)
+               return -ENOMEM;
+
+       if (cmd == USBTMC488_REQUEST_REN_CONTROL) {
+               rv = copy_from_user(&val, arg, sizeof(val));
+               if (rv) {
+                       rv = -EFAULT;
+                       goto exit;
+               }
+               wValue = val ? 1 : 0;
+       } else {
+               wValue = 0;
+       }
+
+       rv = usb_control_msg(data->usb_dev,
+                       usb_rcvctrlpipe(data->usb_dev, 0),
+                       cmd,
+                       USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
+                       wValue,
+                       data->ifnum,
+                       buffer, 0x01, USBTMC_TIMEOUT);
+       if (rv < 0) {
+               dev_err(dev, "simple usb_control_msg failed %d\n", rv);
+               goto exit;
+       } else if (rv != 1) {
+               dev_warn(dev, "simple usb_control_msg returned %d\n", rv);
+               rv = -EIO;
+               goto exit;
+       }
+
+       if (buffer[0] != USBTMC_STATUS_SUCCESS) {
+               dev_err(dev, "simple control status returned %x\n", buffer[0]);
+               rv = -EIO;
+               goto exit;
+       }
+       rv = 0;
+
+ exit:
+       kfree(buffer);
+       return rv;
+}
+
 /*
  * Sends a REQUEST_DEV_DEP_MSG_IN message on the Bulk-IN endpoint.
  * @transfer_size: number of bytes to request from the device.
@@ -1183,6 +1238,21 @@ static long usbtmc_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
        case USBTMC488_IOCTL_READ_STB:
                retval = usbtmc488_ioctl_read_stb(data, (void __user *)arg);
                break;
+
+       case USBTMC488_IOCTL_REN_CONTROL:
+               retval = usbtmc488_ioctl_simple(data, (void __user *)arg,
+                                               USBTMC488_REQUEST_REN_CONTROL);
+               break;
+
+       case USBTMC488_IOCTL_GOTO_LOCAL:
+               retval = usbtmc488_ioctl_simple(data, (void __user *)arg,
+                                               USBTMC488_REQUEST_GOTO_LOCAL);
+               break;
+
+       case USBTMC488_IOCTL_LOCAL_LOCKOUT:
+               retval = usbtmc488_ioctl_simple(data, (void __user *)arg,
+                                               USBTMC488_REQUEST_LOCAL_LOCKOUT);
+               break;
        }
 
 skip_io_on_zombie:

diff --git a/include/uapi/linux/usb/tmc.h b/include/uapi/linux/usb/tmc.h
index b512fb2d403ec9720073516cc3d9df596fcbaff4..2e59d9c50b8d739855f87989f09e2ed32ce1a4e6 100644 (file)
--- a/include/uapi/linux/usb/tmc.h
+++ b/include/uapi/linux/usb/tmc.h
@@ -33,6 +33,9 @@
 #define USBTMC_REQUEST_GET_CAPABILITIES                        7
 #define USBTMC_REQUEST_INDICATOR_PULSE                 64
 #define USBTMC488_REQUEST_READ_STATUS_BYTE             128
+#define USBTMC488_REQUEST_REN_CONTROL                  160
+#define USBTMC488_REQUEST_GOTO_LOCAL                   161
+#define USBTMC488_REQUEST_LOCAL_LOCKOUT                        162
 
 /* Request values for USBTMC driver's ioctl entry point */
 #define USBTMC_IOC_NR                  91
@@ -44,6 +47,9 @@
 #define USBTMC_IOCTL_CLEAR_IN_HALT     _IO(USBTMC_IOC_NR, 7)
 #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)
+#define USBTMC488_IOCTL_GOTO_LOCAL     _IO(USBTMC_IOC_NR, 20)
+#define USBTMC488_IOCTL_LOCAL_LOCKOUT  _IO(USBTMC_IOC_NR, 21)
 
 /* Driver encoded usb488 capabilities */
 #define USBTMC488_CAPABILITY_TRIGGER         1