diff options
Diffstat (limited to 'drivers/usb/class/usbtmc.c')
| -rw-r--r-- | drivers/usb/class/usbtmc.c | 84 |
1 files changed, 69 insertions, 15 deletions
diff --git a/drivers/usb/class/usbtmc.c b/drivers/usb/class/usbtmc.c index b09a527f734..333ee02e7b2 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) |