diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/usb/class/usbtmc.c | 2595 |
1 files changed, 2595 insertions, 0 deletions
diff --git a/drivers/usb/class/usbtmc.c b/drivers/usb/class/usbtmc.c new file mode 100644 index 000000000..311007b1d --- /dev/null +++ b/drivers/usb/class/usbtmc.c @@ -0,0 +1,2595 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * drivers/usb/class/usbtmc.c - USB Test & Measurement class driver + * + * Copyright (C) 2007 Stefan Kopp, Gechingen, Germany + * Copyright (C) 2008 Novell, Inc. + * Copyright (C) 2008 Greg Kroah-Hartman <gregkh@suse.de> + * Copyright (C) 2018 IVI Foundation, Inc. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/fs.h> +#include <linux/uaccess.h> +#include <linux/kref.h> +#include <linux/slab.h> +#include <linux/poll.h> +#include <linux/mutex.h> +#include <linux/usb.h> +#include <linux/compat.h> +#include <linux/usb/tmc.h> + +/* Increment API VERSION when changing tmc.h with new flags or ioctls + * or when changing a significant behavior of the driver. + */ +#define USBTMC_API_VERSION (3) + +#define USBTMC_HEADER_SIZE 12 +#define USBTMC_MINOR_BASE 176 + +/* Minimum USB timeout (in milliseconds) */ +#define USBTMC_MIN_TIMEOUT 100 +/* Default USB timeout (in milliseconds) */ +#define USBTMC_TIMEOUT 5000 + +/* Max number of urbs used in write transfers */ +#define MAX_URBS_IN_FLIGHT 16 +/* 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 + * packet is never read. + */ +#define USBTMC_MAX_READS_TO_CLEAR_BULK_IN 100 + +static const struct usb_device_id usbtmc_devices[] = { + { USB_INTERFACE_INFO(USB_CLASS_APP_SPEC, 3, 0), }, + { USB_INTERFACE_INFO(USB_CLASS_APP_SPEC, 3, 1), }, + { 0, } /* terminating entry */ +}; +MODULE_DEVICE_TABLE(usb, usbtmc_devices); + +/* + * This structure is the capabilities for the device + * 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; + __u8 device_capabilities; + __u8 usb488_interface_capabilities; + __u8 usb488_device_capabilities; +}; + +/* This structure holds private data for each USBTMC device. One copy is + * allocated for each USBTMC device in the driver's probe function. + */ +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; + + u8 bTag; + u8 bTag_last_write; /* needed for abort */ + u8 bTag_last_read; /* needed for abort */ + + /* packet size of IN bulk */ + u16 wMaxPacketSize; + + /* data for interrupt in endpoint handling */ + u8 bNotify1; + u8 bNotify2; + u16 ifnum; + u8 iin_bTag; + u8 *iin_buffer; + atomic_t iin_data_valid; + unsigned int iin_ep; + int iin_ep_present; + int iin_interval; + struct urb *iin_urb; + u16 iin_wMaxPacketSize; + + /* coalesced usb488_caps from usbtmc_dev_capabilities */ + __u8 usb488_caps; + + 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 */ + 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; + + u32 timeout; + u8 srq_byte; + atomic_t srq_asserted; + atomic_t closing; + u8 bmTransferAttributes; /* member of DEV_DEP_MSG_IN */ + + u8 eom_val; + u8 term_char; + bool term_char_enabled; + bool auto_abort; + + spinlock_t err_lock; /* lock for errors */ + + struct usb_anchor submitted; + + /* data for generic_write */ + struct semaphore limit_write_sem; + u32 out_transfer_size; + int out_status; + + /* data for generic_read */ + u32 in_transfer_size; + int in_status; + int in_urbs_used; + struct usb_anchor in_anchor; + wait_queue_head_t wait_bulk_in; +}; + +/* Forward declarations */ +static struct usb_driver usbtmc_driver; +static void usbtmc_draw_down(struct usbtmc_file_data *file_data); + +static void usbtmc_delete(struct kref *kref) +{ + struct usbtmc_device_data *data = to_usbtmc_data(kref); + + usb_put_dev(data->usb_dev); + kfree(data); +} + +static int usbtmc_open(struct inode *inode, struct file *filp) +{ + struct usb_interface *intf; + struct usbtmc_device_data *data; + struct usbtmc_file_data *file_data; + + intf = usb_find_interface(&usbtmc_driver, iminor(inode)); + if (!intf) { + pr_err("can not find device for minor %d", iminor(inode)); + return -ENODEV; + } + + file_data = kzalloc(sizeof(*file_data), GFP_KERNEL); + if (!file_data) + return -ENOMEM; + + spin_lock_init(&file_data->err_lock); + sema_init(&file_data->limit_write_sem, MAX_URBS_IN_FLIGHT); + init_usb_anchor(&file_data->submitted); + init_usb_anchor(&file_data->in_anchor); + init_waitqueue_head(&file_data->wait_bulk_in); + + 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; + + atomic_set(&file_data->closing, 0); + + file_data->timeout = USBTMC_TIMEOUT; + file_data->term_char = '\n'; + file_data->term_char_enabled = 0; + file_data->auto_abort = 0; + file_data->eom_val = 1; + + 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 = file_data; + + return 0; +} + +/* + * usbtmc_flush - called before file handle is closed + */ +static int usbtmc_flush(struct file *file, fl_owner_t id) +{ + struct usbtmc_file_data *file_data; + struct usbtmc_device_data *data; + + file_data = file->private_data; + if (file_data == NULL) + return -ENODEV; + + atomic_set(&file_data->closing, 1); + data = file_data->data; + + /* wait for io to stop */ + mutex_lock(&data->io_mutex); + + usbtmc_draw_down(file_data); + + spin_lock_irq(&file_data->err_lock); + file_data->in_status = 0; + file_data->in_transfer_size = 0; + file_data->in_urbs_used = 0; + file_data->out_status = 0; + file_data->out_transfer_size = 0; + spin_unlock_irq(&file_data->err_lock); + + wake_up_interruptible_all(&data->waitq); + mutex_unlock(&data->io_mutex); + + return 0; +} + +static int usbtmc_release(struct inode *inode, struct file *file) +{ + struct usbtmc_file_data *file_data = file->private_data; + + /* 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; +} + +static int usbtmc_ioctl_abort_bulk_in_tag(struct usbtmc_device_data *data, + u8 tag) +{ + u8 *buffer; + struct device *dev; + int rv; + int n; + int actual; + + dev = &data->intf->dev; + buffer = kmalloc(USBTMC_BUFSIZE, GFP_KERNEL); + if (!buffer) + return -ENOMEM; + + rv = usb_control_msg(data->usb_dev, + usb_rcvctrlpipe(data->usb_dev, 0), + USBTMC_REQUEST_INITIATE_ABORT_BULK_IN, + USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT, + tag, data->bulk_in, + buffer, 2, USB_CTRL_GET_TIMEOUT); + + if (rv < 0) { + dev_err(dev, "usb_control_msg returned %d\n", rv); + goto exit; + } + + dev_dbg(dev, "INITIATE_ABORT_BULK_IN returned %x with tag %02x\n", + buffer[0], buffer[1]); + + if (buffer[0] == USBTMC_STATUS_FAILED) { + /* No transfer in progress and the Bulk-OUT FIFO is empty. */ + rv = 0; + goto exit; + } + + if (buffer[0] == USBTMC_STATUS_TRANSFER_NOT_IN_PROGRESS) { + /* The device returns this status if either: + * - There is a transfer in progress, but the specified bTag + * does not match. + * - There is no transfer in progress, but the Bulk-OUT FIFO + * is not empty. + */ + rv = -ENOMSG; + goto exit; + } + + if (buffer[0] != USBTMC_STATUS_SUCCESS) { + dev_err(dev, "INITIATE_ABORT_BULK_IN returned %x\n", + buffer[0]); + rv = -EPERM; + goto exit; + } + + n = 0; + +usbtmc_abort_bulk_in_status: + dev_dbg(dev, "Reading from bulk in EP\n"); + + /* Data must be present. So use low timeout 300 ms */ + actual = 0; + rv = usb_bulk_msg(data->usb_dev, + usb_rcvbulkpipe(data->usb_dev, + data->bulk_in), + buffer, USBTMC_BUFSIZE, + &actual, 300); + + print_hex_dump_debug("usbtmc ", DUMP_PREFIX_NONE, 16, 1, + buffer, actual, true); + + n++; + + if (rv < 0) { + dev_err(dev, "usb_bulk_msg returned %d\n", rv); + if (rv != -ETIMEDOUT) + goto exit; + } + + if (actual == USBTMC_BUFSIZE) + goto usbtmc_abort_bulk_in_status; + + if (n >= USBTMC_MAX_READS_TO_CLEAR_BULK_IN) { + dev_err(dev, "Couldn't clear device buffer within %d cycles\n", + USBTMC_MAX_READS_TO_CLEAR_BULK_IN); + rv = -EPERM; + goto exit; + } + + rv = usb_control_msg(data->usb_dev, + usb_rcvctrlpipe(data->usb_dev, 0), + USBTMC_REQUEST_CHECK_ABORT_BULK_IN_STATUS, + USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT, + 0, data->bulk_in, buffer, 0x08, + USB_CTRL_GET_TIMEOUT); + + if (rv < 0) { + dev_err(dev, "usb_control_msg returned %d\n", rv); + goto exit; + } + + dev_dbg(dev, "CHECK_ABORT_BULK_IN returned %x\n", buffer[0]); + + if (buffer[0] == USBTMC_STATUS_SUCCESS) { + rv = 0; + goto exit; + } + + if (buffer[0] != USBTMC_STATUS_PENDING) { + dev_err(dev, "CHECK_ABORT_BULK_IN returned %x\n", buffer[0]); + rv = -EPERM; + goto exit; + } + + if ((buffer[1] & 1) > 0) { + /* The device has 1 or more queued packets the Host can read */ + goto usbtmc_abort_bulk_in_status; + } + + /* The Host must send CHECK_ABORT_BULK_IN_STATUS at a later time. */ + rv = -EAGAIN; +exit: + kfree(buffer); + return rv; +} + +static int usbtmc_ioctl_abort_bulk_in(struct usbtmc_device_data *data) +{ + return usbtmc_ioctl_abort_bulk_in_tag(data, data->bTag_last_read); +} + +static int usbtmc_ioctl_abort_bulk_out_tag(struct usbtmc_device_data *data, + u8 tag) +{ + struct device *dev; + u8 *buffer; + int rv; + int n; + + dev = &data->intf->dev; + + buffer = kmalloc(8, GFP_KERNEL); + if (!buffer) + return -ENOMEM; + + rv = usb_control_msg(data->usb_dev, + usb_rcvctrlpipe(data->usb_dev, 0), + USBTMC_REQUEST_INITIATE_ABORT_BULK_OUT, + USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT, + tag, data->bulk_out, + buffer, 2, USB_CTRL_GET_TIMEOUT); + + if (rv < 0) { + dev_err(dev, "usb_control_msg returned %d\n", rv); + goto exit; + } + + dev_dbg(dev, "INITIATE_ABORT_BULK_OUT returned %x\n", buffer[0]); + + if (buffer[0] != USBTMC_STATUS_SUCCESS) { + dev_err(dev, "INITIATE_ABORT_BULK_OUT returned %x\n", + buffer[0]); + rv = -EPERM; + goto exit; + } + + n = 0; + +usbtmc_abort_bulk_out_check_status: + /* do not stress device with subsequent requests */ + msleep(50); + rv = usb_control_msg(data->usb_dev, + usb_rcvctrlpipe(data->usb_dev, 0), + USBTMC_REQUEST_CHECK_ABORT_BULK_OUT_STATUS, + USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT, + 0, data->bulk_out, buffer, 0x08, + USB_CTRL_GET_TIMEOUT); + n++; + if (rv < 0) { + dev_err(dev, "usb_control_msg returned %d\n", rv); + goto exit; + } + + dev_dbg(dev, "CHECK_ABORT_BULK_OUT returned %x\n", buffer[0]); + + if (buffer[0] == USBTMC_STATUS_SUCCESS) + goto usbtmc_abort_bulk_out_clear_halt; + + if ((buffer[0] == USBTMC_STATUS_PENDING) && + (n < USBTMC_MAX_READS_TO_CLEAR_BULK_IN)) + goto usbtmc_abort_bulk_out_check_status; + + rv = -EPERM; + goto exit; + +usbtmc_abort_bulk_out_clear_halt: + rv = usb_clear_halt(data->usb_dev, + usb_sndbulkpipe(data->usb_dev, data->bulk_out)); + + if (rv < 0) { + dev_err(dev, "usb_control_msg returned %d\n", rv); + goto exit; + } + rv = 0; + +exit: + kfree(buffer); + return rv; +} + +static int usbtmc_ioctl_abort_bulk_out(struct usbtmc_device_data *data) +{ + return usbtmc_ioctl_abort_bulk_out_tag(data, data->bTag_last_write); +} + +static int usbtmc_get_stb(struct usbtmc_file_data *file_data, __u8 *stb) +{ + struct usbtmc_device_data *data = file_data->data; + struct device *dev = &data->intf->dev; + u8 *buffer; + u8 tag; + int rv; + + dev_dbg(dev, "Enter ioctl_read_stb iin_ep_present: %d\n", + data->iin_ep_present); + + buffer = kmalloc(8, GFP_KERNEL); + if (!buffer) + return -ENOMEM; + + atomic_set(&data->iin_data_valid, 0); + + rv = usb_control_msg(data->usb_dev, + usb_rcvctrlpipe(data->usb_dev, 0), + USBTMC488_REQUEST_READ_STATUS_BYTE, + USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE, + data->iin_bTag, + data->ifnum, + buffer, 0x03, USB_CTRL_GET_TIMEOUT); + if (rv < 0) { + dev_err(dev, "stb usb_control_msg returned %d\n", rv); + goto exit; + } + + if (buffer[0] != USBTMC_STATUS_SUCCESS) { + dev_err(dev, "control status returned %x\n", buffer[0]); + rv = -EIO; + goto exit; + } + + if (data->iin_ep_present) { + rv = wait_event_interruptible_timeout( + data->waitq, + atomic_read(&data->iin_data_valid) != 0, + file_data->timeout); + if (rv < 0) { + dev_dbg(dev, "wait interrupted %d\n", rv); + goto exit; + } + + if (rv == 0) { + dev_dbg(dev, "wait timed out\n"); + rv = -ETIMEDOUT; + goto exit; + } + + tag = data->bNotify1 & 0x7f; + if (tag != data->iin_bTag) { + dev_err(dev, "expected bTag %x got %x\n", + data->iin_bTag, tag); + } + + *stb = data->bNotify2; + } else { + *stb = buffer[2]; + } + + dev_dbg(dev, "stb:0x%02x received %d\n", (unsigned int)*stb, rv); + + exit: + /* bump interrupt bTag */ + data->iin_bTag += 1; + if (data->iin_bTag > 127) + /* 1 is for SRQ see USBTMC-USB488 subclass spec section 4.3.1 */ + data->iin_bTag = 2; + + kfree(buffer); + return rv; +} + +static int usbtmc488_ioctl_read_stb(struct usbtmc_file_data *file_data, + void __user *arg) +{ + int srq_asserted = 0; + __u8 stb; + int rv; + + rv = usbtmc_get_stb(file_data, &stb); + + if (rv > 0) { + srq_asserted = atomic_xchg(&file_data->srq_asserted, + srq_asserted); + if (srq_asserted) + stb |= 0x40; /* Set RQS bit */ + + rv = put_user(stb, (__u8 __user *)arg); + } + return rv; + +} + +static int usbtmc_ioctl_get_srq_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 stb = 0; + int rv; + + spin_lock_irq(&data->dev_lock); + srq_asserted = atomic_xchg(&file_data->srq_asserted, srq_asserted); + + if (srq_asserted) { + stb = file_data->srq_byte; + spin_unlock_irq(&data->dev_lock); + rv = put_user(stb, (__u8 __user *)arg); + } else { + spin_unlock_irq(&data->dev_lock); + rv = -ENOMSG; + } + + dev_dbg(dev, "stb:0x%02x with srq received %d\n", (unsigned int)stb, rv); + + return rv; +} + +static int usbtmc488_ioctl_wait_srq(struct usbtmc_file_data *file_data, + __u32 __user *arg) +{ + struct usbtmc_device_data *data = file_data->data; + struct device *dev = &data->intf->dev; + int rv; + u32 timeout; + unsigned long expire; + + if (!data->iin_ep_present) { + dev_dbg(dev, "no interrupt endpoint present\n"); + return -EFAULT; + } + + if (get_user(timeout, arg)) + return -EFAULT; + + expire = msecs_to_jiffies(timeout); + + mutex_unlock(&data->io_mutex); + + rv = wait_event_interruptible_timeout( + data->waitq, + atomic_read(&file_data->srq_asserted) != 0 || + atomic_read(&file_data->closing), + expire); + + mutex_lock(&data->io_mutex); + + /* Note! disconnect or close could be called in the meantime */ + if (atomic_read(&file_data->closing) || data->zombie) + rv = -ENODEV; + + if (rv < 0) { + /* dev can be invalid now! */ + pr_debug("%s - wait interrupted %d\n", __func__, rv); + return rv; + } + + if (rv == 0) { + dev_dbg(dev, "%s - wait timed out\n", __func__); + return -ETIMEDOUT; + } + + dev_dbg(dev, "%s - srq asserted\n", __func__); + return 0; +} + +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, USB_CTRL_GET_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 TRIGGER Bulk-OUT command message + * See the USBTMC-USB488 specification, Table 2. + * + * Also updates bTag_last_write. + */ +static int usbtmc488_ioctl_trigger(struct usbtmc_file_data *file_data) +{ + struct usbtmc_device_data *data = file_data->data; + int retval; + u8 *buffer; + int actual; + + buffer = kzalloc(USBTMC_HEADER_SIZE, GFP_KERNEL); + if (!buffer) + return -ENOMEM; + + buffer[0] = 128; + buffer[1] = data->bTag; + buffer[2] = ~data->bTag; + + retval = usb_bulk_msg(data->usb_dev, + usb_sndbulkpipe(data->usb_dev, + data->bulk_out), + buffer, USBTMC_HEADER_SIZE, + &actual, file_data->timeout); + + /* Store bTag (in case we need to abort) */ + data->bTag_last_write = data->bTag; + + /* Increment bTag -- and increment again if zero */ + data->bTag++; + if (!data->bTag) + data->bTag++; + + kfree(buffer); + if (retval < 0) { + dev_err(&data->intf->dev, "%s returned %d\n", + __func__, retval); + return retval; + } + + return 0; +} + +static struct urb *usbtmc_create_urb(void) +{ + const size_t bufsize = USBTMC_BUFSIZE; + u8 *dmabuf = NULL; + struct urb *urb = usb_alloc_urb(0, GFP_KERNEL); + + if (!urb) + return NULL; + + dmabuf = kmalloc(bufsize, GFP_KERNEL); + if (!dmabuf) { + usb_free_urb(urb); + return NULL; + } + + urb->transfer_buffer = dmabuf; + urb->transfer_buffer_length = bufsize; + urb->transfer_flags |= URB_FREE_BUFFER; + return urb; +} + +static void usbtmc_read_bulk_cb(struct urb *urb) +{ + struct usbtmc_file_data *file_data = urb->context; + int status = urb->status; + unsigned long flags; + + /* sync/async unlink faults aren't errors */ + if (status) { + if (!(/* status == -ENOENT || */ + status == -ECONNRESET || + status == -EREMOTEIO || /* Short packet */ + status == -ESHUTDOWN)) + dev_err(&file_data->data->intf->dev, + "%s - nonzero read bulk status received: %d\n", + __func__, status); + + spin_lock_irqsave(&file_data->err_lock, flags); + if (!file_data->in_status) + file_data->in_status = status; + spin_unlock_irqrestore(&file_data->err_lock, flags); + } + + spin_lock_irqsave(&file_data->err_lock, flags); + file_data->in_transfer_size += urb->actual_length; + dev_dbg(&file_data->data->intf->dev, + "%s - total size: %u current: %d status: %d\n", + __func__, file_data->in_transfer_size, + urb->actual_length, status); + spin_unlock_irqrestore(&file_data->err_lock, flags); + usb_anchor_urb(urb, &file_data->in_anchor); + + wake_up_interruptible(&file_data->wait_bulk_in); + wake_up_interruptible(&file_data->data->waitq); +} + +static inline bool usbtmc_do_transfer(struct usbtmc_file_data *file_data) +{ + bool data_or_error; + + spin_lock_irq(&file_data->err_lock); + data_or_error = !usb_anchor_empty(&file_data->in_anchor) + || file_data->in_status; + spin_unlock_irq(&file_data->err_lock); + dev_dbg(&file_data->data->intf->dev, "%s: returns %d\n", __func__, + data_or_error); + return data_or_error; +} + +static ssize_t usbtmc_generic_read(struct usbtmc_file_data *file_data, + void __user *user_buffer, + u32 transfer_size, + u32 *transferred, + u32 flags) +{ + struct usbtmc_device_data *data = file_data->data; + struct device *dev = &data->intf->dev; + u32 done = 0; + u32 remaining; + const u32 bufsize = USBTMC_BUFSIZE; + int retval = 0; + u32 max_transfer_size; + unsigned long expire; + int bufcount = 1; + int again = 0; + + /* mutex already locked */ + + *transferred = done; + + max_transfer_size = transfer_size; + + if (flags & USBTMC_FLAG_IGNORE_TRAILER) { + /* The device may send extra alignment bytes (up to + * wMaxPacketSize – 1) to avoid sending a zero-length + * packet + */ + remaining = transfer_size; + if ((max_transfer_size % data->wMaxPacketSize) == 0) + max_transfer_size += (data->wMaxPacketSize - 1); + } else { + /* round down to bufsize to avoid truncated data left */ + if (max_transfer_size > bufsize) { + max_transfer_size = + roundup(max_transfer_size + 1 - bufsize, + bufsize); + } + remaining = max_transfer_size; + } + + spin_lock_irq(&file_data->err_lock); + + if (file_data->in_status) { + /* return the very first error */ + retval = file_data->in_status; + spin_unlock_irq(&file_data->err_lock); + goto error; + } + + if (flags & USBTMC_FLAG_ASYNC) { + if (usb_anchor_empty(&file_data->in_anchor)) + again = 1; + + if (file_data->in_urbs_used == 0) { + file_data->in_transfer_size = 0; + file_data->in_status = 0; + } + } else { + file_data->in_transfer_size = 0; + file_data->in_status = 0; + } + + if (max_transfer_size == 0) { + bufcount = 0; + } else { + bufcount = roundup(max_transfer_size, bufsize) / bufsize; + if (bufcount > file_data->in_urbs_used) + bufcount -= file_data->in_urbs_used; + else + bufcount = 0; + + if (bufcount + file_data->in_urbs_used > MAX_URBS_IN_FLIGHT) { + bufcount = MAX_URBS_IN_FLIGHT - + file_data->in_urbs_used; + } + } + spin_unlock_irq(&file_data->err_lock); + + dev_dbg(dev, "%s: requested=%u flags=0x%X size=%u bufs=%d used=%d\n", + __func__, transfer_size, flags, + max_transfer_size, bufcount, file_data->in_urbs_used); + + while (bufcount > 0) { + u8 *dmabuf = NULL; + struct urb *urb = usbtmc_create_urb(); + + if (!urb) { + retval = -ENOMEM; + goto error; + } + + dmabuf = urb->transfer_buffer; + + usb_fill_bulk_urb(urb, data->usb_dev, + usb_rcvbulkpipe(data->usb_dev, data->bulk_in), + dmabuf, bufsize, + usbtmc_read_bulk_cb, file_data); + + usb_anchor_urb(urb, &file_data->submitted); + retval = usb_submit_urb(urb, GFP_KERNEL); + /* urb is anchored. We can release our reference. */ + usb_free_urb(urb); + if (unlikely(retval)) { + usb_unanchor_urb(urb); + goto error; + } + file_data->in_urbs_used++; + bufcount--; + } + + if (again) { + dev_dbg(dev, "%s: ret=again\n", __func__); + return -EAGAIN; + } + + if (user_buffer == NULL) + return -EINVAL; + + expire = msecs_to_jiffies(file_data->timeout); + + while (max_transfer_size > 0) { + u32 this_part; + struct urb *urb = NULL; + + if (!(flags & USBTMC_FLAG_ASYNC)) { + dev_dbg(dev, "%s: before wait time %lu\n", + __func__, expire); + retval = wait_event_interruptible_timeout( + file_data->wait_bulk_in, + usbtmc_do_transfer(file_data), + expire); + + dev_dbg(dev, "%s: wait returned %d\n", + __func__, retval); + + if (retval <= 0) { + if (retval == 0) + retval = -ETIMEDOUT; + goto error; + } + } + + urb = usb_get_from_anchor(&file_data->in_anchor); + if (!urb) { + if (!(flags & USBTMC_FLAG_ASYNC)) { + /* synchronous case: must not happen */ + retval = -EFAULT; + goto error; + } + + /* asynchronous case: ready, do not block or wait */ + *transferred = done; + dev_dbg(dev, "%s: (async) done=%u ret=0\n", + __func__, done); + return 0; + } + + file_data->in_urbs_used--; + + if (max_transfer_size > urb->actual_length) + max_transfer_size -= urb->actual_length; + else + max_transfer_size = 0; + + if (remaining > urb->actual_length) + this_part = urb->actual_length; + else + this_part = remaining; + + print_hex_dump_debug("usbtmc ", DUMP_PREFIX_NONE, 16, 1, + urb->transfer_buffer, urb->actual_length, true); + + if (copy_to_user(user_buffer + done, + urb->transfer_buffer, this_part)) { + usb_free_urb(urb); + retval = -EFAULT; + goto error; + } + + remaining -= this_part; + done += this_part; + + spin_lock_irq(&file_data->err_lock); + if (urb->status) { + /* return the very first error */ + retval = file_data->in_status; + spin_unlock_irq(&file_data->err_lock); + usb_free_urb(urb); + goto error; + } + spin_unlock_irq(&file_data->err_lock); + + if (urb->actual_length < bufsize) { + /* short packet or ZLP received => ready */ + usb_free_urb(urb); + retval = 1; + break; + } + + if (!(flags & USBTMC_FLAG_ASYNC) && + max_transfer_size > (bufsize * file_data->in_urbs_used)) { + /* resubmit, since other buffers still not enough */ + usb_anchor_urb(urb, &file_data->submitted); + retval = usb_submit_urb(urb, GFP_KERNEL); + if (unlikely(retval)) { + usb_unanchor_urb(urb); + usb_free_urb(urb); + goto error; + } + file_data->in_urbs_used++; + } + usb_free_urb(urb); + retval = 0; + } + +error: + *transferred = done; + + dev_dbg(dev, "%s: before kill\n", __func__); + /* Attention: killing urbs can take long time (2 ms) */ + usb_kill_anchored_urbs(&file_data->submitted); + dev_dbg(dev, "%s: after kill\n", __func__); + usb_scuttle_anchored_urbs(&file_data->in_anchor); + file_data->in_urbs_used = 0; + file_data->in_status = 0; /* no spinlock needed here */ + dev_dbg(dev, "%s: done=%u ret=%d\n", __func__, done, retval); + + return retval; +} + +static ssize_t usbtmc_ioctl_generic_read(struct usbtmc_file_data *file_data, + void __user *arg) +{ + struct usbtmc_message msg; + ssize_t retval = 0; + + /* mutex already locked */ + + if (copy_from_user(&msg, arg, sizeof(struct usbtmc_message))) + return -EFAULT; + + retval = usbtmc_generic_read(file_data, msg.message, + msg.transfer_size, &msg.transferred, + msg.flags); + + if (put_user(msg.transferred, + &((struct usbtmc_message __user *)arg)->transferred)) + return -EFAULT; + + return retval; +} + +static void usbtmc_write_bulk_cb(struct urb *urb) +{ + struct usbtmc_file_data *file_data = urb->context; + int wakeup = 0; + unsigned long flags; + + spin_lock_irqsave(&file_data->err_lock, flags); + file_data->out_transfer_size += urb->actual_length; + + /* sync/async unlink faults aren't errors */ + if (urb->status) { + if (!(urb->status == -ENOENT || + urb->status == -ECONNRESET || + urb->status == -ESHUTDOWN)) + dev_err(&file_data->data->intf->dev, + "%s - nonzero write bulk status received: %d\n", + __func__, urb->status); + + if (!file_data->out_status) { + file_data->out_status = urb->status; + wakeup = 1; + } + } + spin_unlock_irqrestore(&file_data->err_lock, flags); + + dev_dbg(&file_data->data->intf->dev, + "%s - write bulk total size: %u\n", + __func__, file_data->out_transfer_size); + + up(&file_data->limit_write_sem); + if (usb_anchor_empty(&file_data->submitted) || wakeup) + wake_up_interruptible(&file_data->data->waitq); +} + +static ssize_t usbtmc_generic_write(struct usbtmc_file_data *file_data, + const void __user *user_buffer, + u32 transfer_size, + u32 *transferred, + u32 flags) +{ + struct usbtmc_device_data *data = file_data->data; + struct device *dev; + u32 done = 0; + u32 remaining; + unsigned long expire; + const u32 bufsize = USBTMC_BUFSIZE; + struct urb *urb = NULL; + int retval = 0; + u32 timeout; + + *transferred = 0; + + /* Get pointer to private data structure */ + dev = &data->intf->dev; + + dev_dbg(dev, "%s: size=%u flags=0x%X sema=%u\n", + __func__, transfer_size, flags, + file_data->limit_write_sem.count); + + if (flags & USBTMC_FLAG_APPEND) { + spin_lock_irq(&file_data->err_lock); + retval = file_data->out_status; + spin_unlock_irq(&file_data->err_lock); + if (retval < 0) + return retval; + } else { + spin_lock_irq(&file_data->err_lock); + file_data->out_transfer_size = 0; + file_data->out_status = 0; + spin_unlock_irq(&file_data->err_lock); + } + + remaining = transfer_size; + if (remaining > INT_MAX) + remaining = INT_MAX; + + timeout = file_data->timeout; + expire = msecs_to_jiffies(timeout); + + while (remaining > 0) { + u32 this_part, aligned; + u8 *buffer = NULL; + + if (flags & USBTMC_FLAG_ASYNC) { + if (down_trylock(&file_data->limit_write_sem)) { + retval = (done)?(0):(-EAGAIN); + goto exit; + } + } else { + retval = down_timeout(&file_data->limit_write_sem, + expire); + if (retval < 0) { + retval = -ETIMEDOUT; + goto error; + } + } + + spin_lock_irq(&file_data->err_lock); + retval = file_data->out_status; + spin_unlock_irq(&file_data->err_lock); + if (retval < 0) { + up(&file_data->limit_write_sem); + goto error; + } + + /* prepare next urb to send */ + urb = usbtmc_create_urb(); + if (!urb) { + retval = -ENOMEM; + up(&file_data->limit_write_sem); + goto error; + } + buffer = urb->transfer_buffer; + + if (remaining > bufsize) + this_part = bufsize; + else + this_part = remaining; + + if (copy_from_user(buffer, user_buffer + done, this_part)) { + retval = -EFAULT; + up(&file_data->limit_write_sem); + goto error; + } + + print_hex_dump_debug("usbtmc ", DUMP_PREFIX_NONE, + 16, 1, buffer, this_part, true); + + /* fill bulk with 32 bit alignment to meet USBTMC specification + * (size + 3 & ~3) rounds up and simplifies user code + */ + aligned = (this_part + 3) & ~3; + dev_dbg(dev, "write(size:%u align:%u done:%u)\n", + (unsigned int)this_part, + (unsigned int)aligned, + (unsigned int)done); + + usb_fill_bulk_urb(urb, data->usb_dev, + usb_sndbulkpipe(data->usb_dev, data->bulk_out), + urb->transfer_buffer, aligned, + usbtmc_write_bulk_cb, file_data); + + usb_anchor_urb(urb, &file_data->submitted); + retval = usb_submit_urb(urb, GFP_KERNEL); + if (unlikely(retval)) { + usb_unanchor_urb(urb); + up(&file_data->limit_write_sem); + goto error; + } + + usb_free_urb(urb); + urb = NULL; /* urb will be finally released by usb driver */ + + remaining -= this_part; + done += this_part; + } + + /* All urbs are on the fly */ + if (!(flags & USBTMC_FLAG_ASYNC)) { + if (!usb_wait_anchor_empty_timeout(&file_data->submitted, + timeout)) { + retval = -ETIMEDOUT; + goto error; + } + } + + retval = 0; + goto exit; + +error: + usb_kill_anchored_urbs(&file_data->submitted); +exit: + usb_free_urb(urb); + + spin_lock_irq(&file_data->err_lock); + if (!(flags & USBTMC_FLAG_ASYNC)) + done = file_data->out_transfer_size; + if (!retval && file_data->out_status) + retval = file_data->out_status; + spin_unlock_irq(&file_data->err_lock); + + *transferred = done; + + dev_dbg(dev, "%s: done=%u, retval=%d, urbstat=%d\n", + __func__, done, retval, file_data->out_status); + + return retval; +} + +static ssize_t usbtmc_ioctl_generic_write(struct usbtmc_file_data *file_data, + void __user *arg) +{ + struct usbtmc_message msg; + ssize_t retval = 0; + + /* mutex already locked */ + + if (copy_from_user(&msg, arg, sizeof(struct usbtmc_message))) + return -EFAULT; + + retval = usbtmc_generic_write(file_data, msg.message, + msg.transfer_size, &msg.transferred, + msg.flags); + + if (put_user(msg.transferred, + &((struct usbtmc_message __user *)arg)->transferred)) + return -EFAULT; + + return retval; +} + +/* + * Get the generic write result + */ +static ssize_t usbtmc_ioctl_write_result(struct usbtmc_file_data *file_data, + void __user *arg) +{ + u32 transferred; + int retval; + + spin_lock_irq(&file_data->err_lock); + transferred = file_data->out_transfer_size; + retval = file_data->out_status; + spin_unlock_irq(&file_data->err_lock); + + if (put_user(transferred, (__u32 __user *)arg)) + return -EFAULT; + + return retval; +} + +/* + * Sends a REQUEST_DEV_DEP_MSG_IN message on the Bulk-OUT endpoint. + * @transfer_size: number of bytes to request from the device. + * + * See the USBTMC specification, Table 4. + * + * Also updates bTag_last_write. + */ +static int send_request_dev_dep_msg_in(struct usbtmc_file_data *file_data, + u32 transfer_size) +{ + struct usbtmc_device_data *data = file_data->data; + int retval; + u8 *buffer; + int actual; + + buffer = kmalloc(USBTMC_HEADER_SIZE, GFP_KERNEL); + if (!buffer) + return -ENOMEM; + /* Setup IO buffer for REQUEST_DEV_DEP_MSG_IN message + * Refer to class specs for details + */ + buffer[0] = 2; + buffer[1] = data->bTag; + buffer[2] = ~data->bTag; + buffer[3] = 0; /* Reserved */ + buffer[4] = transfer_size >> 0; + buffer[5] = transfer_size >> 8; + buffer[6] = transfer_size >> 16; + buffer[7] = transfer_size >> 24; + buffer[8] = file_data->term_char_enabled * 2; + /* Use term character? */ + buffer[9] = file_data->term_char; + buffer[10] = 0; /* Reserved */ + buffer[11] = 0; /* Reserved */ + + /* Send bulk URB */ + retval = usb_bulk_msg(data->usb_dev, + usb_sndbulkpipe(data->usb_dev, + data->bulk_out), + buffer, USBTMC_HEADER_SIZE, + &actual, file_data->timeout); + + /* Store bTag (in case we need to abort) */ + data->bTag_last_write = data->bTag; + + /* Increment bTag -- and increment again if zero */ + data->bTag++; + if (!data->bTag) + data->bTag++; + + kfree(buffer); + if (retval < 0) + dev_err(&data->intf->dev, "%s returned %d\n", + __func__, retval); + + return retval; +} + +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; + const u32 bufsize = USBTMC_BUFSIZE; + u32 n_characters; + u8 *buffer; + int actual; + u32 done = 0; + u32 remaining; + int retval; + + /* Get pointer to private data structure */ + file_data = filp->private_data; + data = file_data->data; + dev = &data->intf->dev; + + buffer = kmalloc(bufsize, GFP_KERNEL); + if (!buffer) + return -ENOMEM; + + mutex_lock(&data->io_mutex); + if (data->zombie) { + retval = -ENODEV; + goto exit; + } + + if (count > INT_MAX) + count = INT_MAX; + + dev_dbg(dev, "%s(count:%zu)\n", __func__, count); + + retval = send_request_dev_dep_msg_in(file_data, count); + + if (retval < 0) { + if (file_data->auto_abort) + usbtmc_ioctl_abort_bulk_out(data); + goto exit; + } + + /* Loop until we have fetched everything we requested */ + remaining = count; + actual = 0; + + /* Send bulk URB */ + retval = usb_bulk_msg(data->usb_dev, + usb_rcvbulkpipe(data->usb_dev, + data->bulk_in), + buffer, bufsize, &actual, + file_data->timeout); + + dev_dbg(dev, "%s: bulk_msg retval(%u), actual(%d)\n", + __func__, retval, actual); + + /* Store bTag (in case we need to abort) */ + data->bTag_last_read = data->bTag; + + if (retval < 0) { + if (file_data->auto_abort) + usbtmc_ioctl_abort_bulk_in(data); + goto exit; + } + + /* Sanity checks for the header */ + if (actual < USBTMC_HEADER_SIZE) { + dev_err(dev, "Device sent too small first packet: %u < %u\n", + actual, USBTMC_HEADER_SIZE); + if (file_data->auto_abort) + usbtmc_ioctl_abort_bulk_in(data); + goto exit; + } + + if (buffer[0] != 2) { + dev_err(dev, "Device sent reply with wrong MsgID: %u != 2\n", + buffer[0]); + if (file_data->auto_abort) + usbtmc_ioctl_abort_bulk_in(data); + goto exit; + } + + if (buffer[1] != data->bTag_last_write) { + dev_err(dev, "Device sent reply with wrong bTag: %u != %u\n", + buffer[1], data->bTag_last_write); + if (file_data->auto_abort) + usbtmc_ioctl_abort_bulk_in(data); + goto exit; + } + + /* How many characters did the instrument send? */ + n_characters = buffer[4] + + (buffer[5] << 8) + + (buffer[6] << 16) + + (buffer[7] << 24); + + file_data->bmTransferAttributes = buffer[8]; + + dev_dbg(dev, "Bulk-IN header: N_characters(%u), bTransAttr(%u)\n", + n_characters, buffer[8]); + + if (n_characters > remaining) { + dev_err(dev, "Device wants to return more data than requested: %u > %zu\n", + n_characters, count); + if (file_data->auto_abort) + usbtmc_ioctl_abort_bulk_in(data); + goto exit; + } + + print_hex_dump_debug("usbtmc ", DUMP_PREFIX_NONE, + 16, 1, buffer, actual, true); + + remaining = n_characters; + + /* Remove the USBTMC header */ + actual -= USBTMC_HEADER_SIZE; + + /* Remove padding if it exists */ + if (actual > remaining) + actual = remaining; + + remaining -= actual; + + /* Copy buffer to user space */ + if (copy_to_user(buf, &buffer[USBTMC_HEADER_SIZE], actual)) { + /* There must have been an addressing problem */ + retval = -EFAULT; + goto exit; + } + + if ((actual + USBTMC_HEADER_SIZE) == bufsize) { + retval = usbtmc_generic_read(file_data, buf + actual, + remaining, + &done, + USBTMC_FLAG_IGNORE_TRAILER); + if (retval < 0) + goto exit; + } + done += actual; + + /* Update file position value */ + *f_pos = *f_pos + done; + retval = done; + +exit: + mutex_unlock(&data->io_mutex); + kfree(buffer); + return retval; +} + +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; + struct urb *urb = NULL; + ssize_t retval = 0; + u8 *buffer; + u32 remaining, done; + u32 transfersize, aligned, buflen; + + file_data = filp->private_data; + data = file_data->data; + + mutex_lock(&data->io_mutex); + + if (data->zombie) { + retval = -ENODEV; + goto exit; + } + + done = 0; + + spin_lock_irq(&file_data->err_lock); + file_data->out_transfer_size = 0; + file_data->out_status = 0; + spin_unlock_irq(&file_data->err_lock); + + if (!count) + goto exit; + + if (down_trylock(&file_data->limit_write_sem)) { + /* previous calls were async */ + retval = -EBUSY; + goto exit; + } + + urb = usbtmc_create_urb(); + if (!urb) { + retval = -ENOMEM; + up(&file_data->limit_write_sem); + goto exit; + } + + buffer = urb->transfer_buffer; + buflen = urb->transfer_buffer_length; + + if (count > INT_MAX) { + transfersize = INT_MAX; + buffer[8] = 0; + } else { + transfersize = count; + buffer[8] = file_data->eom_val; + } + + /* Setup IO buffer for DEV_DEP_MSG_OUT message */ + buffer[0] = 1; + buffer[1] = data->bTag; + buffer[2] = ~data->bTag; + buffer[3] = 0; /* Reserved */ + buffer[4] = transfersize >> 0; + buffer[5] = transfersize >> 8; + buffer[6] = transfersize >> 16; + buffer[7] = transfersize >> 24; + /* buffer[8] is set above... */ + buffer[9] = 0; /* Reserved */ + buffer[10] = 0; /* Reserved */ + buffer[11] = 0; /* Reserved */ + + remaining = transfersize; + + if (transfersize + USBTMC_HEADER_SIZE > buflen) { + transfersize = buflen - USBTMC_HEADER_SIZE; + aligned = buflen; + } else { + aligned = (transfersize + (USBTMC_HEADER_SIZE + 3)) & ~3; + } + + if (copy_from_user(&buffer[USBTMC_HEADER_SIZE], buf, transfersize)) { + retval = -EFAULT; + up(&file_data->limit_write_sem); + goto exit; + } + + dev_dbg(&data->intf->dev, "%s(size:%u align:%u)\n", __func__, + (unsigned int)transfersize, (unsigned int)aligned); + + print_hex_dump_debug("usbtmc ", DUMP_PREFIX_NONE, + 16, 1, buffer, aligned, true); + + usb_fill_bulk_urb(urb, data->usb_dev, + usb_sndbulkpipe(data->usb_dev, data->bulk_out), + urb->transfer_buffer, aligned, + usbtmc_write_bulk_cb, file_data); + + usb_anchor_urb(urb, &file_data->submitted); + retval = usb_submit_urb(urb, GFP_KERNEL); + if (unlikely(retval)) { + usb_unanchor_urb(urb); + up(&file_data->limit_write_sem); + goto exit; + } + + remaining -= transfersize; + + data->bTag_last_write = data->bTag; + data->bTag++; + + if (!data->bTag) + data->bTag++; + + /* call generic_write even when remaining = 0 */ + retval = usbtmc_generic_write(file_data, buf + transfersize, remaining, + &done, USBTMC_FLAG_APPEND); + /* truncate alignment bytes */ + if (done > remaining) + done = remaining; + + /*add size of first urb*/ + done += transfersize; + + if (retval < 0) { + usb_kill_anchored_urbs(&file_data->submitted); + + dev_err(&data->intf->dev, + "Unable to send data, error %d\n", (int)retval); + if (file_data->auto_abort) + usbtmc_ioctl_abort_bulk_out(data); + goto exit; + } + + retval = done; +exit: + usb_free_urb(urb); + mutex_unlock(&data->io_mutex); + return retval; +} + +static int usbtmc_ioctl_clear(struct usbtmc_device_data *data) +{ + struct device *dev; + u8 *buffer; + int rv; + int n; + int actual = 0; + + dev = &data->intf->dev; + + dev_dbg(dev, "Sending INITIATE_CLEAR request\n"); + + buffer = kmalloc(USBTMC_BUFSIZE, GFP_KERNEL); + if (!buffer) + return -ENOMEM; + + rv = usb_control_msg(data->usb_dev, + usb_rcvctrlpipe(data->usb_dev, 0), + USBTMC_REQUEST_INITIATE_CLEAR, + USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE, + 0, 0, buffer, 1, USB_CTRL_GET_TIMEOUT); + if (rv < 0) { + dev_err(dev, "usb_control_msg returned %d\n", rv); + goto exit; + } + + dev_dbg(dev, "INITIATE_CLEAR returned %x\n", buffer[0]); + + if (buffer[0] != USBTMC_STATUS_SUCCESS) { + dev_err(dev, "INITIATE_CLEAR returned %x\n", buffer[0]); + rv = -EPERM; + goto exit; + } + + n = 0; + +usbtmc_clear_check_status: + + dev_dbg(dev, "Sending CHECK_CLEAR_STATUS request\n"); + + rv = usb_control_msg(data->usb_dev, + usb_rcvctrlpipe(data->usb_dev, 0), + USBTMC_REQUEST_CHECK_CLEAR_STATUS, + USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE, + 0, 0, buffer, 2, USB_CTRL_GET_TIMEOUT); + if (rv < 0) { + dev_err(dev, "usb_control_msg returned %d\n", rv); + goto exit; + } + + dev_dbg(dev, "CHECK_CLEAR_STATUS returned %x\n", buffer[0]); + + if (buffer[0] == USBTMC_STATUS_SUCCESS) + goto usbtmc_clear_bulk_out_halt; + + if (buffer[0] != USBTMC_STATUS_PENDING) { + dev_err(dev, "CHECK_CLEAR_STATUS returned %x\n", buffer[0]); + rv = -EPERM; + goto exit; + } + + if ((buffer[1] & 1) != 0) { + do { + dev_dbg(dev, "Reading from bulk in EP\n"); + + actual = 0; + rv = usb_bulk_msg(data->usb_dev, + usb_rcvbulkpipe(data->usb_dev, + data->bulk_in), + buffer, USBTMC_BUFSIZE, + &actual, USB_CTRL_GET_TIMEOUT); + + print_hex_dump_debug("usbtmc ", DUMP_PREFIX_NONE, + 16, 1, buffer, actual, true); + + n++; + + if (rv < 0) { + dev_err(dev, "usb_control_msg returned %d\n", + rv); + goto exit; + } + } while ((actual == USBTMC_BUFSIZE) && + (n < USBTMC_MAX_READS_TO_CLEAR_BULK_IN)); + } else { + /* do not stress device with subsequent requests */ + msleep(50); + n++; + } + + if (n >= USBTMC_MAX_READS_TO_CLEAR_BULK_IN) { + dev_err(dev, "Couldn't clear device buffer within %d cycles\n", + USBTMC_MAX_READS_TO_CLEAR_BULK_IN); + rv = -EPERM; + goto exit; + } + + goto usbtmc_clear_check_status; + +usbtmc_clear_bulk_out_halt: + + rv = usb_clear_halt(data->usb_dev, + usb_sndbulkpipe(data->usb_dev, data->bulk_out)); + if (rv < 0) { + dev_err(dev, "usb_clear_halt returned %d\n", rv); + goto exit; + } + rv = 0; + +exit: + kfree(buffer); + return rv; +} + +static int usbtmc_ioctl_clear_out_halt(struct usbtmc_device_data *data) +{ + int rv; + + rv = usb_clear_halt(data->usb_dev, + usb_sndbulkpipe(data->usb_dev, data->bulk_out)); + + if (rv < 0) + dev_err(&data->usb_dev->dev, "%s returned %d\n", __func__, rv); + return rv; +} + +static int usbtmc_ioctl_clear_in_halt(struct usbtmc_device_data *data) +{ + int rv; + + rv = usb_clear_halt(data->usb_dev, + usb_rcvbulkpipe(data->usb_dev, data->bulk_in)); + + if (rv < 0) + dev_err(&data->usb_dev->dev, "%s returned %d\n", __func__, rv); + return rv; +} + +static int usbtmc_ioctl_cancel_io(struct usbtmc_file_data *file_data) +{ + spin_lock_irq(&file_data->err_lock); + file_data->in_status = -ECANCELED; + file_data->out_status = -ECANCELED; + spin_unlock_irq(&file_data->err_lock); + usb_kill_anchored_urbs(&file_data->submitted); + return 0; +} + +static int usbtmc_ioctl_cleanup_io(struct usbtmc_file_data *file_data) +{ + usb_kill_anchored_urbs(&file_data->submitted); + usb_scuttle_anchored_urbs(&file_data->in_anchor); + spin_lock_irq(&file_data->err_lock); + file_data->in_status = 0; + file_data->in_transfer_size = 0; + file_data->out_status = 0; + file_data->out_transfer_size = 0; + spin_unlock_irq(&file_data->err_lock); + + file_data->in_urbs_used = 0; + return 0; +} + +static int get_capabilities(struct usbtmc_device_data *data) +{ + struct device *dev = &data->usb_dev->dev; + char *buffer; + int rv = 0; + + buffer = kmalloc(0x18, GFP_KERNEL); + if (!buffer) + return -ENOMEM; + + rv = usb_control_msg(data->usb_dev, usb_rcvctrlpipe(data->usb_dev, 0), + USBTMC_REQUEST_GET_CAPABILITIES, + USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE, + 0, 0, buffer, 0x18, USB_CTRL_GET_TIMEOUT); + if (rv < 0) { + dev_err(dev, "usb_control_msg returned %d\n", rv); + goto err_out; + } + + dev_dbg(dev, "GET_CAPABILITIES returned %x\n", buffer[0]); + 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]; + data->usb488_caps = (buffer[14] & 0x07) | ((buffer[15] & 0x0f) << 4); + rv = 0; + +err_out: + kfree(buffer); + return rv; +} + +#define capability_attribute(name) \ +static ssize_t name##_show(struct device *dev, \ + struct device_attribute *attr, char *buf) \ +{ \ + struct usb_interface *intf = to_usb_interface(dev); \ + struct usbtmc_device_data *data = usb_get_intfdata(intf); \ + \ + return sprintf(buf, "%d\n", data->capabilities.name); \ +} \ +static DEVICE_ATTR_RO(name) + +capability_attribute(interface_capabilities); +capability_attribute(device_capabilities); +capability_attribute(usb488_interface_capabilities); +capability_attribute(usb488_device_capabilities); + +static struct attribute *usbtmc_attrs[] = { + &dev_attr_interface_capabilities.attr, + &dev_attr_device_capabilities.attr, + &dev_attr_usb488_interface_capabilities.attr, + &dev_attr_usb488_device_capabilities.attr, + NULL, +}; +ATTRIBUTE_GROUPS(usbtmc); + +static int usbtmc_ioctl_indicator_pulse(struct usbtmc_device_data *data) +{ + struct device *dev; + u8 *buffer; + int rv; + + dev = &data->intf->dev; + + buffer = kmalloc(2, GFP_KERNEL); + if (!buffer) + return -ENOMEM; + + rv = usb_control_msg(data->usb_dev, + usb_rcvctrlpipe(data->usb_dev, 0), + USBTMC_REQUEST_INDICATOR_PULSE, + USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE, + 0, 0, buffer, 0x01, USB_CTRL_GET_TIMEOUT); + + if (rv < 0) { + dev_err(dev, "usb_control_msg returned %d\n", rv); + goto exit; + } + + dev_dbg(dev, "INDICATOR_PULSE returned %x\n", buffer[0]); + + if (buffer[0] != USBTMC_STATUS_SUCCESS) { + dev_err(dev, "INDICATOR_PULSE returned %x\n", buffer[0]); + rv = -EPERM; + goto exit; + } + rv = 0; + +exit: + kfree(buffer); + 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 int is_in, pipe; + unsigned long res; + + res = copy_from_user(&request, arg, sizeof(struct usbtmc_ctrlrequest)); + if (res) + return -EFAULT; + + if (request.req.wLength > USBTMC_BUFSIZE) + return -EMSGSIZE; + if (request.req.wLength == 0) /* Length-0 requests are never IN */ + request.req.bRequestType &= ~USB_DIR_IN; + + is_in = request.req.bRequestType & USB_DIR_IN; + + if (request.req.wLength) { + buffer = kmalloc(request.req.wLength, GFP_KERNEL); + if (!buffer) + return -ENOMEM; + + if (!is_in) { + /* Send control data to device */ + res = copy_from_user(buffer, request.data, + request.req.wLength); + if (res) { + rv = -EFAULT; + goto exit; + } + } + } + + if (is_in) + pipe = usb_rcvctrlpipe(data->usb_dev, 0); + else + pipe = usb_sndctrlpipe(data->usb_dev, 0); + rv = usb_control_msg(data->usb_dev, + pipe, + 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 && is_in) { + /* Read control data from device */ + res = copy_to_user(request.data, buffer, rv); + if (res) + rv = -EFAULT; + } + + exit: + kfree(buffer); + return rv; +} + +/* + * Get the usb timeout value + */ +static int usbtmc_ioctl_get_timeout(struct usbtmc_file_data *file_data, + void __user *arg) +{ + u32 timeout; + + timeout = file_data->timeout; + + return put_user(timeout, (__u32 __user *)arg); +} + +/* + * Set the usb timeout value + */ +static int usbtmc_ioctl_set_timeout(struct usbtmc_file_data *file_data, + void __user *arg) +{ + u32 timeout; + + if (get_user(timeout, (__u32 __user *)arg)) + return -EFAULT; + + /* Note that timeout = 0 means + * MAX_SCHEDULE_TIMEOUT in usb_control_msg + */ + if (timeout < USBTMC_MIN_TIMEOUT) + return -EINVAL; + + file_data->timeout = timeout; + + return 0; +} + +/* + * enables/disables sending EOM on write + */ +static int usbtmc_ioctl_eom_enable(struct usbtmc_file_data *file_data, + void __user *arg) +{ + u8 eom_enable; + + if (copy_from_user(&eom_enable, arg, sizeof(eom_enable))) + return -EFAULT; + + if (eom_enable > 1) + return -EINVAL; + + file_data->eom_val = eom_enable; + + return 0; +} + +/* + * Configure termination character for read() + */ +static int usbtmc_ioctl_config_termc(struct usbtmc_file_data *file_data, + void __user *arg) +{ + struct usbtmc_termchar termc; + + if (copy_from_user(&termc, arg, sizeof(termc))) + return -EFAULT; + + if ((termc.term_char_enabled > 1) || + (termc.term_char_enabled && + !(file_data->data->capabilities.device_capabilities & 1))) + return -EINVAL; + + file_data->term_char = termc.term_char; + file_data->term_char_enabled = termc.term_char_enabled; + + return 0; +} + +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; + __u8 tmp_byte; + + file_data = file->private_data; + data = file_data->data; + + mutex_lock(&data->io_mutex); + if (data->zombie) { + retval = -ENODEV; + goto skip_io_on_zombie; + } + + switch (cmd) { + case USBTMC_IOCTL_CLEAR_OUT_HALT: + retval = usbtmc_ioctl_clear_out_halt(data); + break; + + case USBTMC_IOCTL_CLEAR_IN_HALT: + retval = usbtmc_ioctl_clear_in_halt(data); + break; + + case USBTMC_IOCTL_INDICATOR_PULSE: + retval = usbtmc_ioctl_indicator_pulse(data); + break; + + case USBTMC_IOCTL_CLEAR: + retval = usbtmc_ioctl_clear(data); + break; + + case USBTMC_IOCTL_ABORT_BULK_OUT: + retval = usbtmc_ioctl_abort_bulk_out(data); + break; + + case USBTMC_IOCTL_ABORT_BULK_IN: + 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); + break; + + case USBTMC_IOCTL_SET_TIMEOUT: + retval = usbtmc_ioctl_set_timeout(file_data, + (void __user *)arg); + break; + + case USBTMC_IOCTL_EOM_ENABLE: + retval = usbtmc_ioctl_eom_enable(file_data, + (void __user *)arg); + break; + + case USBTMC_IOCTL_CONFIG_TERMCHAR: + retval = usbtmc_ioctl_config_termc(file_data, + (void __user *)arg); + break; + + case USBTMC_IOCTL_WRITE: + retval = usbtmc_ioctl_generic_write(file_data, + (void __user *)arg); + break; + + case USBTMC_IOCTL_READ: + retval = usbtmc_ioctl_generic_read(file_data, + (void __user *)arg); + break; + + case USBTMC_IOCTL_WRITE_RESULT: + retval = usbtmc_ioctl_write_result(file_data, + (void __user *)arg); + break; + + case USBTMC_IOCTL_API_VERSION: + retval = put_user(USBTMC_API_VERSION, + (__u32 __user *)arg); + break; + + case USBTMC488_IOCTL_GET_CAPS: + retval = put_user(data->usb488_caps, + (unsigned char __user *)arg); + break; + + case USBTMC488_IOCTL_READ_STB: + retval = usbtmc488_ioctl_read_stb(file_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; + + case USBTMC488_IOCTL_TRIGGER: + retval = usbtmc488_ioctl_trigger(file_data); + break; + + case USBTMC488_IOCTL_WAIT_SRQ: + retval = usbtmc488_ioctl_wait_srq(file_data, + (__u32 __user *)arg); + break; + + case USBTMC_IOCTL_MSG_IN_ATTR: + retval = put_user(file_data->bmTransferAttributes, + (__u8 __user *)arg); + break; + + case USBTMC_IOCTL_AUTO_ABORT: + retval = get_user(tmp_byte, (unsigned char __user *)arg); + if (retval == 0) + file_data->auto_abort = !!tmp_byte; + break; + + case USBTMC_IOCTL_GET_STB: + retval = usbtmc_get_stb(file_data, &tmp_byte); + if (retval > 0) + retval = put_user(tmp_byte, (__u8 __user *)arg); + break; + + case USBTMC_IOCTL_GET_SRQ_STB: + retval = usbtmc_ioctl_get_srq_stb(file_data, + (void __user *)arg); + break; + + case USBTMC_IOCTL_CANCEL_IO: + retval = usbtmc_ioctl_cancel_io(file_data); + break; + + case USBTMC_IOCTL_CLEANUP_IO: + retval = usbtmc_ioctl_cleanup_io(file_data); + break; + } + +skip_io_on_zombie: + mutex_unlock(&data->io_mutex); + return retval; +} + +static int usbtmc_fasync(int fd, struct file *file, int on) +{ + struct usbtmc_file_data *file_data = file->private_data; + + return fasync_helper(fd, file, on, &file_data->data->fasync); +} + +static __poll_t usbtmc_poll(struct file *file, poll_table *wait) +{ + 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); + + if (data->zombie) { + mask = EPOLLHUP | EPOLLERR; + goto no_poll; + } + + poll_wait(file, &data->waitq, wait); + + /* Note that EPOLLPRI is now assigned to SRQ, and + * EPOLLIN|EPOLLRDNORM to normal read data. + */ + mask = 0; + if (atomic_read(&file_data->srq_asserted)) + mask |= EPOLLPRI; + + /* Note that the anchor submitted includes all urbs for BULK IN + * and OUT. So EPOLLOUT is signaled when BULK OUT is empty and + * all BULK IN urbs are completed and moved to in_anchor. + */ + if (usb_anchor_empty(&file_data->submitted)) + mask |= (EPOLLOUT | EPOLLWRNORM); + if (!usb_anchor_empty(&file_data->in_anchor)) + mask |= (EPOLLIN | EPOLLRDNORM); + + spin_lock_irq(&file_data->err_lock); + if (file_data->in_status || file_data->out_status) + mask |= EPOLLERR; + spin_unlock_irq(&file_data->err_lock); + + dev_dbg(&data->intf->dev, "poll mask = %x\n", mask); + +no_poll: + mutex_unlock(&data->io_mutex); + return mask; +} + +static const struct file_operations fops = { + .owner = THIS_MODULE, + .read = usbtmc_read, + .write = usbtmc_write, + .open = usbtmc_open, + .release = usbtmc_release, + .flush = usbtmc_flush, + .unlocked_ioctl = usbtmc_ioctl, + .compat_ioctl = compat_ptr_ioctl, + .fasync = usbtmc_fasync, + .poll = usbtmc_poll, + .llseek = default_llseek, +}; + +static struct usb_class_driver usbtmc_class = { + .name = "usbtmc%d", + .fops = &fops, + .minor_base = USBTMC_MINOR_BASE, +}; + +static void usbtmc_interrupt(struct urb *urb) +{ + struct usbtmc_device_data *data = urb->context; + struct device *dev = &data->intf->dev; + int status = urb->status; + int rv; + + dev_dbg(&data->intf->dev, "int status: %d len %d\n", + status, urb->actual_length); + + switch (status) { + case 0: /* SUCCESS */ + /* check for valid STB notification */ + if (data->iin_buffer[0] > 0x81) { + data->bNotify1 = data->iin_buffer[0]; + data->bNotify2 = data->iin_buffer[1]; + atomic_set(&data->iin_data_valid, 1); + wake_up_interruptible(&data->waitq); + goto exit; + } + /* 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_PRI); + + 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]); + break; + case -EOVERFLOW: + dev_err(dev, "overflow with length %d, actual length is %d\n", + data->iin_wMaxPacketSize, urb->actual_length); + fallthrough; + default: + /* urb terminated, clean up */ + dev_dbg(dev, "urb terminated, status: %d\n", status); + return; + } +exit: + rv = usb_submit_urb(urb, GFP_ATOMIC); + if (rv) + dev_err(dev, "usb_submit_urb failed: %d\n", rv); +} + +static void usbtmc_free_int(struct usbtmc_device_data *data) +{ + if (!data->iin_ep_present || !data->iin_urb) + return; + usb_kill_urb(data->iin_urb); + kfree(data->iin_buffer); + data->iin_buffer = NULL; + usb_free_urb(data->iin_urb); + data->iin_urb = NULL; + kref_put(&data->kref, usbtmc_delete); +} + +static int usbtmc_probe(struct usb_interface *intf, + const struct usb_device_id *id) +{ + struct usbtmc_device_data *data; + struct usb_host_interface *iface_desc; + struct usb_endpoint_descriptor *bulk_in, *bulk_out, *int_in; + int retcode; + + dev_dbg(&intf->dev, "%s called\n", __func__); + + data = kzalloc(sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->intf = intf; + data->id = id; + data->usb_dev = usb_get_dev(interface_to_usbdev(intf)); + usb_set_intfdata(intf, data); + kref_init(&data->kref); + mutex_init(&data->io_mutex); + init_waitqueue_head(&data->waitq); + atomic_set(&data->iin_data_valid, 0); + INIT_LIST_HEAD(&data->file_list); + spin_lock_init(&data->dev_lock); + + data->zombie = 0; + + /* Initialize USBTMC bTag and other fields */ + data->bTag = 1; + /* 2 <= bTag <= 127 USBTMC-USB488 subclass specification 4.3.1 */ + data->iin_bTag = 2; + + /* USBTMC devices have only one setting, so use that */ + iface_desc = data->intf->cur_altsetting; + data->ifnum = iface_desc->desc.bInterfaceNumber; + + /* Find bulk endpoints */ + retcode = usb_find_common_endpoints(iface_desc, + &bulk_in, &bulk_out, NULL, NULL); + if (retcode) { + dev_err(&intf->dev, "bulk endpoints not found\n"); + goto err_put; + } + + retcode = -EINVAL; + data->bulk_in = bulk_in->bEndpointAddress; + data->wMaxPacketSize = usb_endpoint_maxp(bulk_in); + if (!data->wMaxPacketSize) + goto err_put; + dev_dbg(&intf->dev, "Found bulk in endpoint at %u\n", data->bulk_in); + + data->bulk_out = bulk_out->bEndpointAddress; + dev_dbg(&intf->dev, "Found Bulk out endpoint at %u\n", data->bulk_out); + + /* Find int endpoint */ + retcode = usb_find_int_in_endpoint(iface_desc, &int_in); + if (!retcode) { + data->iin_ep_present = 1; + data->iin_ep = int_in->bEndpointAddress; + data->iin_wMaxPacketSize = usb_endpoint_maxp(int_in); + data->iin_interval = int_in->bInterval; + dev_dbg(&intf->dev, "Found Int in endpoint at %u\n", + data->iin_ep); + } + + retcode = get_capabilities(data); + if (retcode) + dev_err(&intf->dev, "can't read capabilities\n"); + + if (data->iin_ep_present) { + /* allocate int urb */ + data->iin_urb = usb_alloc_urb(0, GFP_KERNEL); + if (!data->iin_urb) { + retcode = -ENOMEM; + goto error_register; + } + + /* Protect interrupt in endpoint data until iin_urb is freed */ + kref_get(&data->kref); + + /* allocate buffer for interrupt in */ + data->iin_buffer = kmalloc(data->iin_wMaxPacketSize, + GFP_KERNEL); + if (!data->iin_buffer) { + retcode = -ENOMEM; + goto error_register; + } + + /* fill interrupt urb */ + usb_fill_int_urb(data->iin_urb, data->usb_dev, + usb_rcvintpipe(data->usb_dev, data->iin_ep), + data->iin_buffer, data->iin_wMaxPacketSize, + usbtmc_interrupt, + data, data->iin_interval); + + retcode = usb_submit_urb(data->iin_urb, GFP_KERNEL); + if (retcode) { + dev_err(&intf->dev, "Failed to submit iin_urb\n"); + goto error_register; + } + } + + retcode = usb_register_dev(intf, &usbtmc_class); + if (retcode) { + dev_err(&intf->dev, "Not able to get a minor (base %u, slice default): %d\n", + USBTMC_MINOR_BASE, + retcode); + goto error_register; + } + dev_dbg(&intf->dev, "Using minor number %d\n", intf->minor); + + return 0; + +error_register: + usbtmc_free_int(data); +err_put: + kref_put(&data->kref, usbtmc_delete); + return retcode; +} + +static void usbtmc_disconnect(struct usb_interface *intf) +{ + struct usbtmc_device_data *data = usb_get_intfdata(intf); + struct list_head *elem; + + usb_deregister_dev(intf, &usbtmc_class); + mutex_lock(&data->io_mutex); + data->zombie = 1; + wake_up_interruptible_all(&data->waitq); + list_for_each(elem, &data->file_list) { + struct usbtmc_file_data *file_data; + + file_data = list_entry(elem, + struct usbtmc_file_data, + file_elem); + usb_kill_anchored_urbs(&file_data->submitted); + usb_scuttle_anchored_urbs(&file_data->in_anchor); + } + mutex_unlock(&data->io_mutex); + usbtmc_free_int(data); + kref_put(&data->kref, usbtmc_delete); +} + +static void usbtmc_draw_down(struct usbtmc_file_data *file_data) +{ + int time; + + time = usb_wait_anchor_empty_timeout(&file_data->submitted, 1000); + if (!time) + usb_kill_anchored_urbs(&file_data->submitted); + usb_scuttle_anchored_urbs(&file_data->in_anchor); +} + +static int usbtmc_suspend(struct usb_interface *intf, pm_message_t message) +{ + struct usbtmc_device_data *data = usb_get_intfdata(intf); + struct list_head *elem; + + if (!data) + return 0; + + mutex_lock(&data->io_mutex); + list_for_each(elem, &data->file_list) { + struct usbtmc_file_data *file_data; + + file_data = list_entry(elem, + struct usbtmc_file_data, + file_elem); + usbtmc_draw_down(file_data); + } + + if (data->iin_ep_present && data->iin_urb) + usb_kill_urb(data->iin_urb); + + mutex_unlock(&data->io_mutex); + return 0; +} + +static int usbtmc_resume(struct usb_interface *intf) +{ + struct usbtmc_device_data *data = usb_get_intfdata(intf); + int retcode = 0; + + if (data->iin_ep_present && data->iin_urb) + retcode = usb_submit_urb(data->iin_urb, GFP_KERNEL); + if (retcode) + dev_err(&intf->dev, "Failed to submit iin_urb\n"); + + return retcode; +} + +static int usbtmc_pre_reset(struct usb_interface *intf) +{ + struct usbtmc_device_data *data = usb_get_intfdata(intf); + struct list_head *elem; + + if (!data) + return 0; + + mutex_lock(&data->io_mutex); + + list_for_each(elem, &data->file_list) { + struct usbtmc_file_data *file_data; + + file_data = list_entry(elem, + struct usbtmc_file_data, + file_elem); + usbtmc_ioctl_cancel_io(file_data); + } + + return 0; +} + +static int usbtmc_post_reset(struct usb_interface *intf) +{ + struct usbtmc_device_data *data = usb_get_intfdata(intf); + + mutex_unlock(&data->io_mutex); + + return 0; +} + +static struct usb_driver usbtmc_driver = { + .name = "usbtmc", + .id_table = usbtmc_devices, + .probe = usbtmc_probe, + .disconnect = usbtmc_disconnect, + .suspend = usbtmc_suspend, + .resume = usbtmc_resume, + .pre_reset = usbtmc_pre_reset, + .post_reset = usbtmc_post_reset, + .dev_groups = usbtmc_groups, +}; + +module_usb_driver(usbtmc_driver); + +MODULE_LICENSE("GPL"); |