--- /dev/null
+/*
+ * Boot HSIC Class Driver -
+ *
+ * Copyright (C) 2001-2004 Greg Kroah-Hartman (greg@kroah.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation, version 2.
+ *
+ * This driver is based on the 2.6.3 version of drivers/usb/usb-skeleton.c
+ * but has been rewritten to be easier to read and use.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/kref.h>
+#include <linux/uaccess.h>
+#include <linux/usb.h>
+#include <linux/mutex.h>
+
+
+/* Version Information */
+#define DRIVER_VERSION "v0.1 (2012/01/03)"
+#define DRIVER_AUTHOR "Picard Ronan <ronan.picard@renesasmobile.com>"
+#define DRIVER_DESC "Modem boot HSIC USB driver for HakuyaS"
+
+/* Define these values to match your devices */
+#define USB_RENESAS_VENDOR_ID 0x045B
+#define USB_HAKUYAS_PRODUCT_ID 0x0213
+
+/* table of devices that work with this driver */
+static const struct usb_device_id renesas_table[] = {
+ { USB_DEVICE(USB_RENESAS_VENDOR_ID, USB_HAKUYAS_PRODUCT_ID) },
+ { } /* Terminating entry */
+};
+MODULE_DEVICE_TABLE(usb, renesas_table);
+
+
+/* Get a minor range for your devices from the usb maintainer */
+#define USB_MODEM_MINOR_BASE 192
+
+/* our private defines. if this grows any larger, use your own .h file */
+#define MAX_TRANSFER (PAGE_SIZE - 512)
+/* MAX_TRANSFER is chosen so that the VM is not stressed by
+ allocations > PAGE_SIZE and the number of packets in a page
+ is an integer 512 is the largest possible packet on EHCI */
+#define WRITES_IN_FLIGHT 8
+/* arbitrarily chosen */
+
+/* Structure to hold all of our device specific stuff */
+struct boot_hsic {
+ /* the usb device for this device */
+ struct usb_device *udev;
+ /* the interface for this device */
+ struct usb_interface *interface;
+ /* limiting the number of writes in progress */
+ struct semaphore limit_sem;
+ /* in case we need to retract our submissions */
+ struct usb_anchor submitted;
+ /* the urb to read data with */
+ struct urb *bulk_in_urb;
+ /* the buffer to receive data */
+ unsigned char *bulk_in_buffer;
+ /* the size of the receive buffer */
+ size_t bulk_in_size;
+ /* number of bytes in the buffer */
+ size_t bulk_in_filled;
+ /* already copied to user space */
+ size_t bulk_in_copied;
+ /* the address of the bulk in endpoint */
+ __u8 bulk_in_endpointAddr;
+ /* the address of the bulk out endpoint */
+ __u8 bulk_out_endpointAddr;
+ /* the last request tanked */
+ int errors;
+ /* count the number of openers */
+ int open_count;
+ /* a read is going on */
+ bool ongoing_read;
+ /* indicates we haven't processed the urb */
+ bool processed_urb;
+ /* lock for errors */
+ spinlock_t err_lock;
+
+ struct kref kref;
+ /* synchronize I/O with disconnect */
+ struct mutex io_mutex;
+ /* to wait for an ongoing read */
+ struct completion bulk_in_completion;
+};
+
+static struct usb_driver boot_hsic_driver;
+
+/**
+ * boot_hsic_delete
+ */
+static void boot_hsic_delete(struct boot_hsic *dev)
+{
+ printk(KERN_DEBUG "boot_hsic_delete.\n");
+ /* free data structures */
+ usb_free_urb(dev->bulk_in_urb);
+ usb_put_dev(dev->udev);
+ kfree(dev->bulk_in_buffer);
+ kfree(dev);
+}
+
+/**
+ * modem_hsic_open
+ */
+static int modem_hsic_open(struct inode *inode, struct file *file)
+{
+ struct boot_hsic *dev = NULL;
+ struct usb_interface *interface;
+ int subminor;
+ int retval = 0;
+
+ subminor = iminor(inode);
+ printk(KERN_DEBUG "modem_hsic_open");
+
+ interface = usb_find_interface(&boot_hsic_driver, subminor);
+ if (!interface) {
+ err("%s - error, can't find device for minor %d",
+ __func__, subminor);
+ retval = -ENODEV;
+ goto exit;
+ }
+
+ dev = usb_get_intfdata(interface);
+ if (!dev) {
+ retval = -ENODEV;
+ goto exit;
+ }
+
+
+ /* lock the device to allow correctly handling errors
+ * in resumption */
+ mutex_lock(&dev->io_mutex);
+
+ /* allow opening only once */
+ if (dev->open_count) {
+ retval = -EBUSY;
+ mutex_unlock(&dev->io_mutex);
+ goto exit;
+ }
+ dev->open_count = 1;
+
+ /* save our object in the file's private structure */
+ file->private_data = dev;
+ mutex_unlock(&dev->io_mutex);
+
+exit:
+ return retval;
+}
+
+
+/**
+ * modem_hsic_release
+ */
+static int modem_hsic_release(struct inode *inode, struct file *file)
+{
+ struct boot_hsic *dev = NULL;
+ int retval = 0;
+
+ printk(KERN_DEBUG "modem_hsic_release.\n");
+ dev = file->private_data;
+ if (dev == NULL)
+ return -ENODEV;
+
+ /* allow the device to be autosuspended */
+ /* mutex_lock(&dev->io_mutex); */
+
+ if (dev->open_count != 1) {
+ err("%s - error, device not opened exactly once, %d",
+ __func__, dev->open_count);
+ retval = -ENODEV;
+ goto unlock_exit;
+ }
+
+ if (dev->udev == NULL) {
+ /* the device was unplugged before the file was released */
+ dev->open_count = 0;
+ /* unlock here as frees dev */
+ /* mutex_unlock(&dev->io_mutex); */
+ boot_hsic_delete(dev);
+ } else
+ /* decrement the count on our device */
+ dev->open_count = 0;
+
+ /* mutex_unlock(&dev->io_mutex); */
+
+ return 0;
+
+unlock_exit:
+ /* mutex_unlock(&dev->io_mutex); */
+ return retval;
+}
+
+
+static void modem_read_bulk_callback(struct urb *urb)
+{
+ struct boot_hsic *dev;
+ printk(KERN_DEBUG "modem_read_bulk_callback");
+
+ dev = urb->context;
+
+ spin_lock(&dev->err_lock);
+ /* sync/async unlink faults aren't errors */
+ if (urb->status) {
+ if (!(urb->status == -ENOENT ||
+ urb->status == -ECONNRESET ||
+ urb->status == -ESHUTDOWN))
+ err("%s - nonzero write bulk status received: %d",
+ __func__, urb->status);
+
+ dev->errors = urb->status;
+ } else {
+ dev->bulk_in_filled = urb->actual_length;
+ printk(KERN_DEBUG "modem_read_bulk_callback, length = %d",
+ urb->actual_length);
+ }
+ dev->ongoing_read = 0;
+ spin_unlock(&dev->err_lock);
+
+ complete(&dev->bulk_in_completion);
+}
+
+static int modem_do_read_io(struct boot_hsic *dev, size_t count)
+{
+ int rv;
+ printk(KERN_DEBUG "modem_do_read_io");
+ /* prepare a read */
+ usb_fill_bulk_urb(dev->bulk_in_urb,
+ dev->udev,
+ usb_rcvbulkpipe(dev->udev,
+ dev->bulk_in_endpointAddr),
+ dev->bulk_in_buffer,
+ min(dev->bulk_in_size, count),
+ modem_read_bulk_callback,
+ dev);
+ /* tell everybody to leave the URB alone */
+ spin_lock_irq(&dev->err_lock);
+ dev->ongoing_read = 1;
+ spin_unlock_irq(&dev->err_lock);
+
+ /* do it */
+ rv = usb_submit_urb(dev->bulk_in_urb, GFP_KERNEL);
+ if (rv < 0) {
+ err("%s - failed submitting read urb, error %d",
+ __func__, rv);
+ dev->bulk_in_filled = 0;
+ rv = (rv == -ENOMEM) ? rv : -EIO;
+ spin_lock_irq(&dev->err_lock);
+ dev->ongoing_read = 0;
+ spin_unlock_irq(&dev->err_lock);
+ }
+
+ return rv;
+}
+
+/**
+ * modem_hsic_read
+ */
+static ssize_t modem_hsic_read(struct file *file, char *buffer, size_t count,
+ loff_t *ppos)
+{
+ struct boot_hsic *dev;
+ int retval;
+ bool ongoing_io;
+
+
+ printk(KERN_DEBUG "modem_hsic_read.\n");
+ dev = file->private_data;
+ dev->processed_urb = 0;
+
+ /* verify that the device wasn't unplugged */
+ if (dev->udev == NULL) {
+ retval = -ENODEV;
+ err("%s : No device or device unplugged %d",
+ __func__, retval);
+ goto exit;
+ }
+
+ /* if we cannot read at all, return EOF */
+ if (!count) {
+ printk(KERN_DEBUG "%s :read request of 0 bytes\n", __func__);
+ return 0;
+ }
+
+ if (!dev->interface) { /* disconnect() was called */
+ retval = -ENODEV;
+ err("%s: disconnect %d", __func__, retval);
+ goto exit;
+ }
+
+ if (!dev->processed_urb) {
+ /*
+ * the URB hasn't been processed
+ * do it now
+ */
+ dev->processed_urb = 1;
+
+ retval = modem_do_read_io(dev, count);
+ if (retval < 0) {
+ printk(KERN_DEBUG "%s : modem_do_read_io2, retval = =%d\n",
+ __func__, retval);
+ goto exit;
+ } else
+ printk(KERN_DEBUG "%s : modem_do_read_io3, retval = =%d\n",
+ __func__, retval);
+ }
+
+ /* if IO is under way, we must not touch things */
+retry:
+ spin_lock_irq(&dev->err_lock);
+ ongoing_io = dev->ongoing_read;
+ spin_unlock_irq(&dev->err_lock);
+
+ /* errors must be reported */
+ retval = dev->errors;
+ if (retval < 0) {
+ /* any error is reported once */
+ dev->errors = 0;
+ /* to preserve notifications about reset */
+ retval = (retval == -EPIPE) ? retval : -EIO;
+ /* no data to deliver */
+ dev->bulk_in_filled = 0;
+ /* report it */
+ goto exit;
+ }
+
+ /*
+ * if the buffer is filled we may satisfy the read
+ * else we need to start IO
+ */
+
+ wait_for_completion_interruptible(&dev->bulk_in_completion);
+
+ if (dev->bulk_in_filled) {
+ /* we had read data */
+ if (copy_to_user(buffer, dev->bulk_in_buffer,
+ dev->bulk_in_filled)) {
+ retval = -EFAULT;
+ printk(KERN_DEBUG "%s : copy_to_user retval =%d\n",
+ __func__, retval);
+ dev->bulk_in_filled = 0;
+ goto exit;
+ } else {
+ retval = dev->bulk_in_filled;
+ printk(KERN_DEBUG "%s : copy_to_user bytes_read =%d\n",
+ __func__, dev->bulk_in_filled);
+ dev->bulk_in_filled = 0;
+ goto success;
+ }
+ }
+ goto retry;
+exit:
+ return retval;
+
+success:
+ usb_free_urb(dev->bulk_in_urb);
+ kfree(dev->bulk_in_buffer);
+
+ dev->bulk_in_buffer = kmalloc(dev->bulk_in_size, GFP_KERNEL);
+ if (!dev->bulk_in_buffer) {
+ err("Could not allocate bulk_in_buffer");
+ retval = -ENOMEM;
+ goto exit;
+ }
+ dev->bulk_in_urb = usb_alloc_urb(0, GFP_KERNEL);
+ if (!dev->bulk_in_urb) {
+ err("Could not allocate bulk_in_urb");
+ retval = -ENOMEM;
+ goto exit;
+ }
+ /* mutex_unlock(&dev->io_mutex); */
+ return retval;
+
+}
+
+static void modem_write_bulk_callback(struct urb *urb)
+{
+ struct boot_hsic *dev;
+
+ /* printk(KERN_DEBUG "modem_write_bulk_callback : enter\n"); */
+
+ dev = urb->context;
+
+ /* sync/async unlink faults aren't errors */
+ if (urb->status) {
+ if (!(urb->status == -ENOENT ||
+ urb->status == -ECONNRESET ||
+ urb->status == -ESHUTDOWN))
+ err("%s - nonzero write bulk status received: %d",
+ __func__, urb->status);
+
+ spin_lock(&dev->err_lock);
+ dev->errors = urb->status;
+ spin_unlock(&dev->err_lock);
+ }
+
+ /* free up our allocated buffer */
+ usb_free_coherent(urb->dev, urb->transfer_buffer_length,
+ urb->transfer_buffer, urb->transfer_dma);
+
+ up(&dev->limit_sem);
+}
+
+/**
+ * modem_hsic_write
+ */
+static ssize_t modem_hsic_write(struct file *file,
+ const char __user *user_buffer,
+ size_t count, loff_t *ppos)
+{
+ struct boot_hsic *dev;
+ int retval = 0;
+ struct urb *urb = NULL;
+ char *buf = NULL;
+ size_t writesize = min_t(size_t, count, 512);
+ dev = file->private_data;
+
+ /* printk(KERN_DEBUG "modem_hsic_write : enter\n"); */
+
+ /* verify that we actually have some data to write */
+ if (count == 0) {
+ err("modem_hsic_write: count == 0");
+ goto exit;
+ }
+
+ /*
+ * limit the number of URBs in flight to stop a user from using up all
+ * RAM
+ */
+ if (!(file->f_flags & O_NONBLOCK)) {
+ retval = -ERESTARTSYS;
+ err("modem_hsic_write: interruptible retval = %d", retval);
+ goto exit;
+ } else {
+ if (down_trylock(&dev->limit_sem)) {
+ retval = -EAGAIN;
+ goto exit;
+ }
+ }
+
+ spin_lock_irq(&dev->err_lock);
+ retval = dev->errors;
+ if (retval < 0) {
+ /* any error is reported once */
+ dev->errors = 0;
+ /* to preserve notifications about reset */
+ retval = (retval == -EPIPE) ? retval : -EIO;
+ }
+ spin_unlock_irq(&dev->err_lock);
+ if (retval < 0) {
+ err("modem_hsic_write: misc error retval = %d",
+ retval);
+ goto error;
+ }
+
+ /* create a urb, and a buffer for BULK OUT,
+ and copy the data to the urb */
+ urb = usb_alloc_urb(0, GFP_KERNEL);
+ if (!urb) {
+ retval = -ENOMEM;
+ err("modem_hsic_write: urb alloc retval = %d",
+ retval);
+ goto error;
+ }
+
+ buf = usb_alloc_coherent(dev->udev, writesize, GFP_KERNEL,
+ &urb->transfer_dma);
+ if (!buf) {
+ retval = -ENOMEM;
+ err("modem_hsic_write: usb_alloc_coherent retval = %d",
+ retval);
+ goto error;
+ }
+
+ if (copy_from_user(buf, user_buffer, writesize)) {
+ retval = -EFAULT;
+ err("modem_hsic_write: copy_from_user retval = %d",
+ retval);
+ goto error;
+ }
+
+ /* this lock makes sure we don't submit URBs to gone devices */
+ mutex_lock(&dev->io_mutex);
+ if (!dev->interface) { /* disconnect() was called */
+ mutex_unlock(&dev->io_mutex);
+ err("modem_hsic_write: interface retval = %d", retval);
+ retval = -ENODEV;
+ goto error;
+ }
+
+ /* initialize the urb properly */
+ usb_fill_bulk_urb(urb, dev->udev,
+ usb_sndbulkpipe(dev->udev,
+ dev->bulk_out_endpointAddr),
+ buf, writesize,
+ modem_write_bulk_callback, dev);
+
+ /* urb->transfer_flags |= URB_ZERO_PACKET; */
+ urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
+
+ /* send the data out the bulk port */
+ retval = usb_submit_urb(urb, GFP_KERNEL);
+ mutex_unlock(&dev->io_mutex);
+ if (retval) {
+ err("%s - failed submitting write urb, error %d", __func__,
+ retval);
+ goto error;
+ }
+
+ /*
+ * release our reference to this urb, the USB core will eventually free
+ * it entirely
+ */
+ usb_free_urb(urb);
+
+ return writesize;
+
+error:
+ printk(KERN_DEBUG "modem_hsic_write : error\n");
+ if (urb) {
+ printk(KERN_DEBUG "modem_hsic_write : error free URB\n");
+
+ usb_free_coherent(dev->udev, writesize, buf, urb->transfer_dma);
+ usb_free_urb(urb);
+ }
+ up(&dev->limit_sem);
+exit:
+ return retval;
+}
+
+/* file operations needed when we register this driver */
+static const struct file_operations boot_hsic_fops = {
+ .owner = THIS_MODULE,
+ .read = modem_hsic_read,
+ .write = modem_hsic_write,
+ .open = modem_hsic_open,
+ .release = modem_hsic_release,
+};
+
+/*
+ * usb class driver info in order to get a minor number from the usb core,
+ * and to have the device registered with the driver core
+ */
+static struct usb_class_driver boot_hsic_class = {
+ .name = "boot_hsic%d",
+ .fops = &boot_hsic_fops,
+ .minor_base = USB_MODEM_MINOR_BASE,
+};
+
+/**
+ * boot_hsic_probe
+ *
+ * Called by the usb core when a new device is connected that it thinks
+ * this driver might be interested in.
+ */
+static int boot_hsic_probe(struct usb_interface *interface,
+ const struct usb_device_id *id)
+{
+ struct boot_hsic *dev = NULL;
+ struct usb_device *udev = interface_to_usbdev(interface);
+ struct usb_host_interface *iface_desc;
+ struct usb_endpoint_descriptor *endpoint;
+ size_t buffer_size;
+ int i;
+ int retval = -ENOMEM;
+
+ /* allocate memory for our device state and initialize it */
+ dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+ if (!dev) {
+ err("Out of memory");
+ goto error;
+ }
+
+ mutex_init(&dev->io_mutex);
+ spin_lock_init(&dev->err_lock);
+ init_completion(&dev->bulk_in_completion);
+ sema_init(&dev->limit_sem, WRITES_IN_FLIGHT);
+
+ dev->udev = usb_get_dev(udev);
+ dev->interface = interface;
+
+ /* set up the endpoint information */
+ /* use only the first bulk-in and bulk-out endpoints */
+ iface_desc = interface->cur_altsetting;
+ for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
+ endpoint = &iface_desc->endpoint[i].desc;
+
+ if (!dev->bulk_in_endpointAddr &&
+ usb_endpoint_is_bulk_in(endpoint)) {
+ /* we found a bulk in endpoint */
+ buffer_size = le16_to_cpu(endpoint->wMaxPacketSize);
+ dev->bulk_in_size = buffer_size;
+ dev->bulk_in_endpointAddr = endpoint->bEndpointAddress;
+ dev->bulk_in_buffer = kmalloc(buffer_size, GFP_KERNEL);
+ if (!dev->bulk_in_buffer) {
+ err("Could not allocate bulk_in_buffer");
+ goto error;
+ }
+ dev->bulk_in_urb = usb_alloc_urb(0, GFP_KERNEL);
+ if (!dev->bulk_in_urb) {
+ err("Could not allocate bulk_in_urb");
+ goto error;
+ }
+ }
+
+ if (!dev->bulk_out_endpointAddr &&
+ usb_endpoint_is_bulk_out(endpoint)) {
+ /* we found a bulk out endpoint */
+ dev->bulk_out_endpointAddr = endpoint->bEndpointAddress;
+ }
+ }
+ if (!(dev->bulk_in_endpointAddr && dev->bulk_out_endpointAddr)) {
+ err("Could not find both bulk-in and bulk-out endpoints");
+ goto error;
+ }
+
+ /* save our data pointer in this interface device */
+ usb_set_intfdata(interface, dev);
+
+ /* we can register the device now, as it is ready */
+ retval = usb_register_dev(interface, &boot_hsic_class);
+ if (retval) {
+ /* something prevented us from registering this driver */
+ err("Not able to get a minor for this device.");
+ usb_set_intfdata(interface, NULL);
+ goto error;
+ }
+
+ /* let the user know what node this device is now attached to */
+ dev_info(&interface->dev,
+ "USB HAKUYA-S device now attached to USBRenesas-%d"
+ "vid 0x%4.4X pid 0x%4.4X\n",
+ interface->minor,
+ le16_to_cpu(udev->descriptor.idVendor),
+ le16_to_cpu(udev->descriptor.idProduct));
+ return 0;
+
+error:
+ if (dev)
+ /* this frees allocated memory */
+ boot_hsic_delete(dev);
+ return retval;
+}
+
+/**
+ * boot_hsic_disconnect
+ *
+ * Called by the usb core when the device is removed from the system.
+ */
+static void boot_hsic_disconnect(struct usb_interface *interface)
+{
+ struct boot_hsic *dev;
+ int minor = interface->minor;
+
+ printk(KERN_DEBUG "boot_hsic_disconnect.\n");
+ dev = usb_get_intfdata(interface);
+ usb_set_intfdata(interface, NULL);
+
+ /* give back our minor */
+ usb_deregister_dev(interface, &boot_hsic_class);
+
+ /* prevent more I/O from starting */
+ mutex_lock(&dev->io_mutex);
+ dev->interface = NULL;
+ /* mutex_unlock(&dev->io_mutex); */
+
+ /* if the device is not opened, then we clean up right now */
+ if (!dev->open_count) {
+ mutex_unlock(&dev->io_mutex);
+ boot_hsic_delete(dev);
+ } else {
+ dev->udev = NULL;
+ mutex_unlock(&dev->io_mutex);
+ }
+
+ /* decrement our usage count */
+ /* boot_hsic_delete(dev); */
+
+ dev_info(&interface->dev,
+ "USB Hakuya Renesas Modem #%d now disconnected",
+ minor);
+}
+
+/* usb specific object needed to register this driver with the usb subsystem */
+static struct usb_driver boot_hsic_driver = {
+ .name = "modem_boot_hsic",
+ .probe = boot_hsic_probe,
+ .disconnect = boot_hsic_disconnect,
+ .id_table = renesas_table,
+};
+
+static int __init boot_hsic_init(void)
+{
+ int result;
+
+ /* register this driver with the USB subsystem */
+ result = usb_register(&boot_hsic_driver);
+ if (result)
+ err("usb_register failed. Error number %d", result);
+
+ return result;
+}
+
+static void __exit boot_hsic_exit(void)
+{
+ /* deregister this driver with the USB subsystem */
+ usb_deregister(&boot_hsic_driver);
+}
+
+module_init(boot_hsic_init);
+module_exit(boot_hsic_exit);
+
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE("GPL");
Code Review / linux-3.10.git / commitdiff