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-rw-r--r--drivers/usb/class/usbtmc.c2554
1 files changed, 2554 insertions, 0 deletions
diff --git a/drivers/usb/class/usbtmc.c b/drivers/usb/class/usbtmc.c
new file mode 100644
index 000000000..76ff18242
--- /dev/null
+++ b/drivers/usb/class/usbtmc.c
@@ -0,0 +1,2554 @@
+// 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 (2)
+
+#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 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;
+ int rv;
+
+ 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);
+
+ 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];
+ }
+
+ rv = put_user(stb, (__u8 __user *)arg);
+ 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_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_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");