summaryrefslogtreecommitdiff
path: root/drivers/usb/class/usbtmc.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/usb/class/usbtmc.c')
-rw-r--r--drivers/usb/class/usbtmc.c84
1 files changed, 69 insertions, 15 deletions
diff --git a/drivers/usb/class/usbtmc.c b/drivers/usb/class/usbtmc.c
index b09a527f7341..333ee02e7b2b 100644
--- a/drivers/usb/class/usbtmc.c
+++ b/drivers/usb/class/usbtmc.c
@@ -57,7 +57,9 @@ MODULE_DEVICE_TABLE(usb, usbtmc_devices);
/*
* This structure is the capabilities for the device
- * See section 4.2.1.8 of the USBTMC specification for details.
+ * See section 4.2.1.8 of the USBTMC specification,
+ * and section 4.2.2 of the USBTMC usb488 subclass
+ * specification for details.
*/
struct usbtmc_dev_capabilities {
__u8 interface_capabilities;
@@ -86,6 +88,8 @@ struct usbtmc_device_data {
bool TermCharEnabled;
bool auto_abort;
+ bool zombie; /* fd of disconnected device */
+
struct usbtmc_dev_capabilities capabilities;
struct kref kref;
struct mutex io_mutex; /* only one i/o function running at a time */
@@ -367,13 +371,13 @@ static ssize_t usbtmc_read(struct file *filp, char __user *buf,
{
struct usbtmc_device_data *data;
struct device *dev;
- unsigned long int n_characters;
+ u32 n_characters;
u8 *buffer;
int actual;
- int done;
- int remaining;
+ size_t done;
+ size_t remaining;
int retval;
- int this_part;
+ size_t this_part;
/* Get pointer to private data structure */
data = filp->private_data;
@@ -384,6 +388,10 @@ static ssize_t usbtmc_read(struct file *filp, char __user *buf,
return -ENOMEM;
mutex_lock(&data->io_mutex);
+ if (data->zombie) {
+ retval = -ENODEV;
+ goto exit;
+ }
remaining = count;
done = 0;
@@ -401,10 +409,10 @@ static ssize_t usbtmc_read(struct file *filp, char __user *buf,
buffer[1] = data->bTag;
buffer[2] = ~(data->bTag);
buffer[3] = 0; /* Reserved */
- buffer[4] = (this_part - 12 - 3) & 255;
- buffer[5] = ((this_part - 12 - 3) >> 8) & 255;
- buffer[6] = ((this_part - 12 - 3) >> 16) & 255;
- buffer[7] = ((this_part - 12 - 3) >> 24) & 255;
+ buffer[4] = (this_part) & 255;
+ buffer[5] = ((this_part) >> 8) & 255;
+ buffer[6] = ((this_part) >> 16) & 255;
+ buffer[7] = ((this_part) >> 24) & 255;
buffer[8] = data->TermCharEnabled * 2;
/* Use term character? */
buffer[9] = data->TermChar;
@@ -455,6 +463,22 @@ static ssize_t usbtmc_read(struct file *filp, char __user *buf,
(buffer[6] << 16) +
(buffer[7] << 24);
+ /* Ensure the instrument doesn't lie about it */
+ if(n_characters > actual - 12) {
+ dev_err(dev, "Device lies about message size: %u > %d\n", n_characters, actual - 12);
+ n_characters = actual - 12;
+ }
+
+ /* Ensure the instrument doesn't send more back than requested */
+ if(n_characters > this_part) {
+ dev_err(dev, "Device returns more than requested: %zu > %zu\n", done + n_characters, done + this_part);
+ n_characters = this_part;
+ }
+
+ /* Bound amount of data received by amount of data requested */
+ if (n_characters > this_part)
+ n_characters = this_part;
+
/* Copy buffer to user space */
if (copy_to_user(buf + done, &buffer[12], n_characters)) {
/* There must have been an addressing problem */
@@ -463,8 +487,11 @@ static ssize_t usbtmc_read(struct file *filp, char __user *buf,
}
done += n_characters;
- if (n_characters < USBTMC_SIZE_IOBUFFER)
+ /* Terminate if end-of-message bit recieved from device */
+ if ((buffer[8] & 0x01) && (actual >= n_characters + 12))
remaining = 0;
+ else
+ remaining -= n_characters;
}
/* Update file position value */
@@ -496,6 +523,10 @@ static ssize_t usbtmc_write(struct file *filp, const char __user *buf,
return -ENOMEM;
mutex_lock(&data->io_mutex);
+ if (data->zombie) {
+ retval = -ENODEV;
+ goto exit;
+ }
remaining = count;
done = 0;
@@ -767,20 +798,21 @@ static int get_capabilities(struct usbtmc_device_data *data)
}
dev_dbg(dev, "GET_CAPABILITIES returned %x\n", buffer[0]);
- dev_dbg(dev, "Interface capabilities are %x\n", buffer[4]);
- dev_dbg(dev, "Device capabilities are %x\n", buffer[5]);
- dev_dbg(dev, "USB488 interface capabilities are %x\n", buffer[14]);
- dev_dbg(dev, "USB488 device capabilities are %x\n", buffer[15]);
if (buffer[0] != USBTMC_STATUS_SUCCESS) {
dev_err(dev, "GET_CAPABILITIES returned %x\n", buffer[0]);
rv = -EPERM;
goto err_out;
}
+ dev_dbg(dev, "Interface capabilities are %x\n", buffer[4]);
+ dev_dbg(dev, "Device capabilities are %x\n", buffer[5]);
+ dev_dbg(dev, "USB488 interface capabilities are %x\n", buffer[14]);
+ dev_dbg(dev, "USB488 device capabilities are %x\n", buffer[15]);
data->capabilities.interface_capabilities = buffer[4];
data->capabilities.device_capabilities = buffer[5];
data->capabilities.usb488_interface_capabilities = buffer[14];
data->capabilities.usb488_device_capabilities = buffer[15];
+ rv = 0;
err_out:
kfree(buffer);
@@ -925,6 +957,10 @@ static long usbtmc_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
data = file->private_data;
mutex_lock(&data->io_mutex);
+ if (data->zombie) {
+ retval = -ENODEV;
+ goto skip_io_on_zombie;
+ }
switch (cmd) {
case USBTMC_IOCTL_CLEAR_OUT_HALT:
@@ -952,6 +988,7 @@ static long usbtmc_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
break;
}
+skip_io_on_zombie:
mutex_unlock(&data->io_mutex);
return retval;
}
@@ -995,6 +1032,7 @@ static int usbtmc_probe(struct usb_interface *intf,
usb_set_intfdata(intf, data);
kref_init(&data->kref);
mutex_init(&data->io_mutex);
+ data->zombie = 0;
/* Initialize USBTMC bTag and other fields */
data->bTag = 1;
@@ -1065,14 +1103,30 @@ static void usbtmc_disconnect(struct usb_interface *intf)
usb_deregister_dev(intf, &usbtmc_class);
sysfs_remove_group(&intf->dev.kobj, &capability_attr_grp);
sysfs_remove_group(&intf->dev.kobj, &data_attr_grp);
+ mutex_lock(&data->io_mutex);
+ data->zombie = 1;
+ mutex_unlock(&data->io_mutex);
kref_put(&data->kref, usbtmc_delete);
}
+static int usbtmc_suspend (struct usb_interface *intf, pm_message_t message)
+{
+ /* this driver does not have pending URBs */
+ return 0;
+}
+
+static int usbtmc_resume (struct usb_interface *intf)
+{
+ return 0;
+}
+
static struct usb_driver usbtmc_driver = {
.name = "usbtmc",
.id_table = usbtmc_devices,
.probe = usbtmc_probe,
- .disconnect = usbtmc_disconnect
+ .disconnect = usbtmc_disconnect,
+ .suspend = usbtmc_suspend,
+ .resume = usbtmc_resume,
};
static int __init usbtmc_init(void)
generated by cgit v1.2.3 (git 2.0.4) at 2024-06-25 09:35:53 +0000