diff options
Diffstat (limited to 'drivers/usb/class/usbtmc.c')
| -rw-r--r-- | drivers/usb/class/usbtmc.c | 136 |
1 files changed, 105 insertions, 31 deletions
diff --git a/drivers/usb/class/usbtmc.c b/drivers/usb/class/usbtmc.c index 529295a17579..db58b84d43ee 100644 --- a/drivers/usb/class/usbtmc.c +++ b/drivers/usb/class/usbtmc.c @@ -67,6 +67,7 @@ struct usbtmc_device_data { const struct usb_device_id *id; struct usb_device *usb_dev; struct usb_interface *intf; + struct list_head file_list; unsigned int bulk_in; unsigned int bulk_out; @@ -87,7 +88,6 @@ struct usbtmc_device_data { int iin_interval; struct urb *iin_urb; u16 iin_wMaxPacketSize; - atomic_t srq_asserted; /* coalesced usb488_caps from usbtmc_dev_capabilities */ __u8 usb488_caps; @@ -104,9 +104,21 @@ struct usbtmc_device_data { struct mutex io_mutex; /* only one i/o function running at a time */ wait_queue_head_t waitq; struct fasync_struct *fasync; + spinlock_t dev_lock; /* lock for file_list */ }; #define to_usbtmc_data(d) container_of(d, struct usbtmc_device_data, kref) +/* + * This structure holds private data for each USBTMC file handle. + */ +struct usbtmc_file_data { + struct usbtmc_device_data *data; + struct list_head file_elem; + + u8 srq_byte; + atomic_t srq_asserted; +}; + /* Forward declarations */ static struct usb_driver usbtmc_driver; @@ -122,7 +134,7 @@ static int usbtmc_open(struct inode *inode, struct file *filp) { struct usb_interface *intf; struct usbtmc_device_data *data; - int retval = 0; + struct usbtmc_file_data *file_data; intf = usb_find_interface(&usbtmc_driver, iminor(inode)); if (!intf) { @@ -130,21 +142,45 @@ static int usbtmc_open(struct inode *inode, struct file *filp) return -ENODEV; } + file_data = kzalloc(sizeof(*file_data), GFP_KERNEL); + if (!file_data) + return -ENOMEM; + data = usb_get_intfdata(intf); /* Protect reference to data from file structure until release */ kref_get(&data->kref); + mutex_lock(&data->io_mutex); + file_data->data = data; + + INIT_LIST_HEAD(&file_data->file_elem); + spin_lock_irq(&data->dev_lock); + list_add_tail(&file_data->file_elem, &data->file_list); + spin_unlock_irq(&data->dev_lock); + mutex_unlock(&data->io_mutex); + /* Store pointer in file structure's private data field */ - filp->private_data = data; + filp->private_data = file_data; - return retval; + return 0; } static int usbtmc_release(struct inode *inode, struct file *file) { - struct usbtmc_device_data *data = file->private_data; + struct usbtmc_file_data *file_data = file->private_data; - kref_put(&data->kref, usbtmc_delete); + /* prevent IO _AND_ usbtmc_interrupt */ + mutex_lock(&file_data->data->io_mutex); + spin_lock_irq(&file_data->data->dev_lock); + + list_del(&file_data->file_elem); + + spin_unlock_irq(&file_data->data->dev_lock); + mutex_unlock(&file_data->data->io_mutex); + + kref_put(&file_data->data->kref, usbtmc_delete); + file_data->data = NULL; + kfree(file_data); return 0; } @@ -369,10 +405,12 @@ exit: return rv; } -static int usbtmc488_ioctl_read_stb(struct usbtmc_device_data *data, +static int usbtmc488_ioctl_read_stb(struct usbtmc_file_data *file_data, void __user *arg) { + struct usbtmc_device_data *data = file_data->data; struct device *dev = &data->intf->dev; + int srq_asserted = 0; u8 *buffer; u8 tag; __u8 stb; @@ -381,15 +419,25 @@ static int usbtmc488_ioctl_read_stb(struct usbtmc_device_data *data, dev_dbg(dev, "Enter ioctl_read_stb iin_ep_present: %d\n", data->iin_ep_present); + spin_lock_irq(&data->dev_lock); + srq_asserted = atomic_xchg(&file_data->srq_asserted, srq_asserted); + if (srq_asserted) { + /* a STB with SRQ is already received */ + stb = file_data->srq_byte; + spin_unlock_irq(&data->dev_lock); + rv = put_user(stb, (__u8 __user *)arg); + dev_dbg(dev, "stb:0x%02x with srq received %d\n", + (unsigned int)stb, rv); + return rv; + } + spin_unlock_irq(&data->dev_lock); + buffer = kmalloc(8, GFP_KERNEL); if (!buffer) return -ENOMEM; atomic_set(&data->iin_data_valid, 0); - /* must issue read_stb before using poll or select */ - atomic_set(&data->srq_asserted, 0); - rv = usb_control_msg(data->usb_dev, usb_rcvctrlpipe(data->usb_dev, 0), USBTMC488_REQUEST_READ_STATUS_BYTE, @@ -435,9 +483,8 @@ static int usbtmc488_ioctl_read_stb(struct usbtmc_device_data *data, stb = buffer[2]; } - rv = copy_to_user(arg, &stb, sizeof(stb)); - if (rv) - rv = -EFAULT; + rv = put_user(stb, (__u8 __user *)arg); + dev_dbg(dev, "stb:0x%02x received %d\n", (unsigned int)stb, rv); exit: /* bump interrupt bTag */ @@ -565,6 +612,7 @@ static int send_request_dev_dep_msg_in(struct usbtmc_device_data *data, size_t t static ssize_t usbtmc_read(struct file *filp, char __user *buf, size_t count, loff_t *f_pos) { + struct usbtmc_file_data *file_data; struct usbtmc_device_data *data; struct device *dev; u32 n_characters; @@ -576,7 +624,8 @@ static ssize_t usbtmc_read(struct file *filp, char __user *buf, size_t this_part; /* Get pointer to private data structure */ - data = filp->private_data; + file_data = filp->private_data; + data = file_data->data; dev = &data->intf->dev; buffer = kmalloc(USBTMC_SIZE_IOBUFFER, GFP_KERNEL); @@ -721,6 +770,7 @@ exit: static ssize_t usbtmc_write(struct file *filp, const char __user *buf, size_t count, loff_t *f_pos) { + struct usbtmc_file_data *file_data; struct usbtmc_device_data *data; u8 *buffer; int retval; @@ -730,7 +780,8 @@ static ssize_t usbtmc_write(struct file *filp, const char __user *buf, int done; int this_part; - data = filp->private_data; + file_data = filp->private_data; + data = file_data->data; buffer = kmalloc(USBTMC_SIZE_IOBUFFER, GFP_KERNEL); if (!buffer) @@ -1140,10 +1191,13 @@ exit: static long usbtmc_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { + struct usbtmc_file_data *file_data; struct usbtmc_device_data *data; int retval = -EBADRQC; - data = file->private_data; + file_data = file->private_data; + data = file_data->data; + mutex_lock(&data->io_mutex); if (data->zombie) { retval = -ENODEV; @@ -1184,7 +1238,8 @@ static long usbtmc_ioctl(struct file *file, unsigned int cmd, unsigned long arg) break; case USBTMC488_IOCTL_READ_STB: - retval = usbtmc488_ioctl_read_stb(data, (void __user *)arg); + retval = usbtmc488_ioctl_read_stb(file_data, + (void __user *)arg); break; case USBTMC488_IOCTL_REN_CONTROL: @@ -1210,14 +1265,15 @@ skip_io_on_zombie: static int usbtmc_fasync(int fd, struct file *file, int on) { - struct usbtmc_device_data *data = file->private_data; + struct usbtmc_file_data *file_data = file->private_data; - return fasync_helper(fd, file, on, &data->fasync); + return fasync_helper(fd, file, on, &file_data->data->fasync); } static __poll_t usbtmc_poll(struct file *file, poll_table *wait) { - struct usbtmc_device_data *data = file->private_data; + struct usbtmc_file_data *file_data = file->private_data; + struct usbtmc_device_data *data = file_data->data; __poll_t mask; mutex_lock(&data->io_mutex); @@ -1229,7 +1285,7 @@ static __poll_t usbtmc_poll(struct file *file, poll_table *wait) poll_wait(file, &data->waitq, wait); - mask = (atomic_read(&data->srq_asserted)) ? EPOLLIN | EPOLLRDNORM : 0; + mask = (atomic_read(&file_data->srq_asserted)) ? EPOLLPRI : 0; no_poll: mutex_unlock(&data->io_mutex); @@ -1276,15 +1332,33 @@ static void usbtmc_interrupt(struct urb *urb) } /* check for SRQ notification */ if (data->iin_buffer[0] == 0x81) { + unsigned long flags; + struct list_head *elem; + if (data->fasync) kill_fasync(&data->fasync, - SIGIO, POLL_IN); + SIGIO, POLL_PRI); - atomic_set(&data->srq_asserted, 1); - wake_up_interruptible(&data->waitq); + spin_lock_irqsave(&data->dev_lock, flags); + list_for_each(elem, &data->file_list) { + struct usbtmc_file_data *file_data; + + file_data = list_entry(elem, + struct usbtmc_file_data, + file_elem); + file_data->srq_byte = data->iin_buffer[1]; + atomic_set(&file_data->srq_asserted, 1); + } + spin_unlock_irqrestore(&data->dev_lock, flags); + + dev_dbg(dev, "srq received bTag %x stb %x\n", + (unsigned int)data->iin_buffer[0], + (unsigned int)data->iin_buffer[1]); + wake_up_interruptible_all(&data->waitq); goto exit; } - dev_warn(dev, "invalid notification: %x\n", data->iin_buffer[0]); + dev_warn(dev, "invalid notification: %x\n", + data->iin_buffer[0]); break; case -EOVERFLOW: dev_err(dev, "overflow with length %d, actual length is %d\n", @@ -1295,6 +1369,7 @@ static void usbtmc_interrupt(struct urb *urb) case -ESHUTDOWN: case -EILSEQ: case -ETIME: + case -EPIPE: /* urb terminated, clean up */ dev_dbg(dev, "urb terminated, status: %d\n", status); return; @@ -1339,7 +1414,9 @@ static int usbtmc_probe(struct usb_interface *intf, mutex_init(&data->io_mutex); init_waitqueue_head(&data->waitq); atomic_set(&data->iin_data_valid, 0); - atomic_set(&data->srq_asserted, 0); + INIT_LIST_HEAD(&data->file_list); + spin_lock_init(&data->dev_lock); + data->zombie = 0; /* Initialize USBTMC bTag and other fields */ @@ -1442,17 +1519,14 @@ err_put: static void usbtmc_disconnect(struct usb_interface *intf) { - struct usbtmc_device_data *data; + struct usbtmc_device_data *data = usb_get_intfdata(intf); - dev_dbg(&intf->dev, "usbtmc_disconnect called\n"); - - data = usb_get_intfdata(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; - wake_up_all(&data->waitq); + wake_up_interruptible_all(&data->waitq); mutex_unlock(&data->io_mutex); usbtmc_free_int(data); kref_put(&data->kref, usbtmc_delete); |