Add USBTMC_IOCTL_CTRL_REQUEST to send arbitrary requests on the
control pipe. Used by specific applications of IVI Foundation,
Inc. to implement VISA API functions: viUsbControlIn/Out.
The maximum length of control request is set to 4k.
Signed-off-by: Guido Kiener <guido.kie...@rohde-schwarz.com>
Reviewed-by: Steve Bayless <steve_bayl...@keysight.com>
---
drivers/usb/class/usbtmc.c | 84 ++++++++++++++++++++++++++++++++++++
include/uapi/linux/usb/tmc.h | 15 +++++++
2 files changed, 99 insertions(+)
diff --git a/drivers/usb/class/usbtmc.c b/drivers/usb/class/usbtmc.c
index 83ffa5a14c3d..3b3b4284d04e 100644
--- a/drivers/usb/class/usbtmc.c
+++ b/drivers/usb/class/usbtmc.c
@@ -5,6 +5,7 @@
* Copyright (C) 2007 Stefan Kopp, Gechingen, Germany
* Copyright (C) 2008 Novell, Inc.
* Copyright (C) 2008 Greg Kroah-Hartman <gre...@suse.de>
+ * Copyright (C) 2018 IVI Foundation, Inc.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
@@ -36,6 +37,9 @@
/* Default USB timeout (in milliseconds) */
#define USBTMC_TIMEOUT 5000
+/* I/O buffer size used in generic read/write functions */
+#define USBTMC_BUFSIZE (4096)
+
/*
* Maximum number of read cycles to empty bulk in endpoint during CLEAR and
* ABORT_BULK_IN requests. Ends the loop if (for whatever reason) a short
@@ -129,6 +133,21 @@ struct usbtmc_file_data {
/* Forward declarations */
static struct usb_driver usbtmc_driver;
+#ifdef CONFIG_COMPAT
+static void __user *u64_to_uptr(u64 value)
+{
+ if (in_compat_syscall())
+ return compat_ptr(value);
+ else
+ return (void __user *)(unsigned long)value;
+}
+#else
+static inline void __user *u64_to_uptr(u64 value)
+{
+ return (void __user *)(unsigned long)value;
+}
+#endif /* CONFIG_COMPAT */
+
static void usbtmc_delete(struct kref *kref)
{
struct usbtmc_device_data *data = to_usbtmc_data(kref);
@@ -1250,6 +1269,67 @@ static int usbtmc_ioctl_indicator_pulse(struct
usbtmc_device_data *data)
return rv;
}
+static int usbtmc_ioctl_request(struct usbtmc_device_data *data,
+ void __user *arg)
+{
+ struct device *dev = &data->intf->dev;
+ struct usbtmc_ctrlrequest request;
+ u8 *buffer = NULL;
+ int rv;
+ unsigned long res;
+
+ res = copy_from_user(&request, arg, sizeof(struct usbtmc_ctrlrequest));
+ if (res)
+ return -EFAULT;
+
+ buffer = kmalloc(request.req.wLength, GFP_KERNEL);
+ if (!buffer)
+ return -ENOMEM;
+
+ if (request.req.wLength > USBTMC_BUFSIZE)
+ return -EMSGSIZE;
+
+ if (request.req.wLength) {
+ buffer = kmalloc(request.req.wLength, GFP_KERNEL);
+ if (!buffer)
+ return -ENOMEM;
+
+ if ((request.req.bRequestType & USB_DIR_IN) == 0) {
+ /* Send control data to device */
+ res = copy_from_user(buffer, u64_to_uptr(request.data),
+ request.req.wLength);
+ if (res) {
+ rv = -EFAULT;
+ goto exit;
+ }
+ }
+ }
+
+ rv = usb_control_msg(data->usb_dev,
+ usb_rcvctrlpipe(data->usb_dev, 0),
+ request.req.bRequest,
+ request.req.bRequestType,
+ request.req.wValue,
+ request.req.wIndex,
+ buffer, request.req.wLength, USB_CTRL_GET_TIMEOUT);
+
+ if (rv < 0) {
+ dev_err(dev, "%s failed %d\n", __func__, rv);
+ goto exit;
+ }
+
+ if (rv && (request.req.bRequestType & USB_DIR_IN)) {
+ /* Read control data from device */
+ res = copy_to_user(u64_to_uptr(request.data), buffer, rv);
+ if (res)
+ rv = -EFAULT;
+ }
+
+ exit:
+ kfree(buffer);
+ return rv;
+}
+
/*
* Get the usb timeout value
*/
@@ -1366,6 +1446,10 @@ static long usbtmc_ioctl(struct file *file, unsigned int
cmd, unsigned long arg)
retval = usbtmc_ioctl_abort_bulk_in(data);
break;
+ case USBTMC_IOCTL_CTRL_REQUEST:
+ retval = usbtmc_ioctl_request(data, (void __user *)arg);
+ break;
+
case USBTMC_IOCTL_GET_TIMEOUT:
retval = usbtmc_ioctl_get_timeout(file_data,
(void __user *)arg);
diff --git a/include/uapi/linux/usb/tmc.h b/include/uapi/linux/usb/tmc.h
index 729af2f861a4..95533118ac34 100644
--- a/include/uapi/linux/usb/tmc.h
+++ b/include/uapi/linux/usb/tmc.h
@@ -4,6 +4,7 @@
* Copyright (C) 2008 Novell, Inc.
* Copyright (C) 2008 Greg Kroah-Hartman <gre...@suse.de>
* Copyright (C) 2015 Dave Penkler <dpenk...@gmail.com>
+ * Copyright (C) 2018 IVI Foundation, Inc.
*
* This file holds USB constants defined by the USB Device Class
* and USB488 Subclass Definitions for Test and Measurement devices
@@ -40,6 +41,19 @@
#define USBTMC488_REQUEST_GOTO_LOCAL 161
#define USBTMC488_REQUEST_LOCAL_LOCKOUT 162
+struct usbtmc_request {
+ __u8 bRequestType;
+ __u8 bRequest;
+ __u16 wValue;
+ __u16 wIndex;
+ __u16 wLength;
+} __attribute__ ((packed));
+
+struct usbtmc_ctrlrequest {
+ struct usbtmc_request req;
+ __u64 data; /* pointer to user space */
+} __attribute__ ((packed));
+
struct usbtmc_termchar {
__u8 term_char;
__u8 term_char_enabled;
@@ -53,6 +67,7 @@ struct usbtmc_termchar {
#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 USBTMC_IOCTL_CTRL_REQUEST _IOWR(USBTMC_IOC_NR, 8, struct
usbtmc_ctrlrequest)
#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)
--
2.17.1
--
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