https://github.com/torvalds/linux
Tip revision: f8788d86ab28f61f7b46eb6be375f8a726783636 authored by Linus Torvalds on 24 February 2020, 00:17:42 UTC
Linux 5.6-rc3
Linux 5.6-rc3
Tip revision: f8788d8
yurex.c
// SPDX-License-Identifier: GPL-2.0
/*
* Driver for Meywa-Denki & KAYAC YUREX
*
* Copyright (C) 2010 Tomoki Sekiyama (tomoki.sekiyama@gmail.com)
*/
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/kref.h>
#include <linux/mutex.h>
#include <linux/uaccess.h>
#include <linux/usb.h>
#include <linux/hid.h>
#define DRIVER_AUTHOR "Tomoki Sekiyama"
#define DRIVER_DESC "Driver for Meywa-Denki & KAYAC YUREX"
#define YUREX_VENDOR_ID 0x0c45
#define YUREX_PRODUCT_ID 0x1010
#define CMD_ACK '!'
#define CMD_ANIMATE 'A'
#define CMD_COUNT 'C'
#define CMD_LED 'L'
#define CMD_READ 'R'
#define CMD_SET 'S'
#define CMD_VERSION 'V'
#define CMD_EOF 0x0d
#define CMD_PADDING 0xff
#define YUREX_BUF_SIZE 8
#define YUREX_WRITE_TIMEOUT (HZ*2)
/* table of devices that work with this driver */
static struct usb_device_id yurex_table[] = {
{ USB_DEVICE(YUREX_VENDOR_ID, YUREX_PRODUCT_ID) },
{ } /* Terminating entry */
};
MODULE_DEVICE_TABLE(usb, yurex_table);
#ifdef CONFIG_USB_DYNAMIC_MINORS
#define YUREX_MINOR_BASE 0
#else
#define YUREX_MINOR_BASE 192
#endif
/* Structure to hold all of our device specific stuff */
struct usb_yurex {
struct usb_device *udev;
struct usb_interface *interface;
__u8 int_in_endpointAddr;
struct urb *urb; /* URB for interrupt in */
unsigned char *int_buffer; /* buffer for intterupt in */
struct urb *cntl_urb; /* URB for control msg */
struct usb_ctrlrequest *cntl_req; /* req for control msg */
unsigned char *cntl_buffer; /* buffer for control msg */
struct kref kref;
struct mutex io_mutex;
unsigned long disconnected:1;
struct fasync_struct *async_queue;
wait_queue_head_t waitq;
spinlock_t lock;
__s64 bbu; /* BBU from device */
};
#define to_yurex_dev(d) container_of(d, struct usb_yurex, kref)
static struct usb_driver yurex_driver;
static const struct file_operations yurex_fops;
static void yurex_control_callback(struct urb *urb)
{
struct usb_yurex *dev = urb->context;
int status = urb->status;
if (status) {
dev_err(&urb->dev->dev, "%s - control failed: %d\n",
__func__, status);
wake_up_interruptible(&dev->waitq);
return;
}
/* on success, sender woken up by CMD_ACK int in, or timeout */
}
static void yurex_delete(struct kref *kref)
{
struct usb_yurex *dev = to_yurex_dev(kref);
dev_dbg(&dev->interface->dev, "%s\n", __func__);
if (dev->cntl_urb) {
usb_kill_urb(dev->cntl_urb);
kfree(dev->cntl_req);
if (dev->cntl_buffer)
usb_free_coherent(dev->udev, YUREX_BUF_SIZE,
dev->cntl_buffer, dev->cntl_urb->transfer_dma);
usb_free_urb(dev->cntl_urb);
}
if (dev->urb) {
usb_kill_urb(dev->urb);
if (dev->int_buffer)
usb_free_coherent(dev->udev, YUREX_BUF_SIZE,
dev->int_buffer, dev->urb->transfer_dma);
usb_free_urb(dev->urb);
}
usb_put_intf(dev->interface);
usb_put_dev(dev->udev);
kfree(dev);
}
/*
* 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 yurex_class = {
.name = "yurex%d",
.fops = &yurex_fops,
.minor_base = YUREX_MINOR_BASE,
};
static void yurex_interrupt(struct urb *urb)
{
struct usb_yurex *dev = urb->context;
unsigned char *buf = dev->int_buffer;
int status = urb->status;
unsigned long flags;
int retval, i;
switch (status) {
case 0: /*success*/
break;
/* The device is terminated or messed up, give up */
case -EOVERFLOW:
dev_err(&dev->interface->dev,
"%s - overflow with length %d, actual length is %d\n",
__func__, YUREX_BUF_SIZE, dev->urb->actual_length);
case -ECONNRESET:
case -ENOENT:
case -ESHUTDOWN:
case -EILSEQ:
case -EPROTO:
case -ETIME:
return;
default:
dev_err(&dev->interface->dev,
"%s - unknown status received: %d\n", __func__, status);
return;
}
/* handle received message */
switch (buf[0]) {
case CMD_COUNT:
case CMD_READ:
if (buf[6] == CMD_EOF) {
spin_lock_irqsave(&dev->lock, flags);
dev->bbu = 0;
for (i = 1; i < 6; i++) {
dev->bbu += buf[i];
if (i != 5)
dev->bbu <<= 8;
}
dev_dbg(&dev->interface->dev, "%s count: %lld\n",
__func__, dev->bbu);
spin_unlock_irqrestore(&dev->lock, flags);
kill_fasync(&dev->async_queue, SIGIO, POLL_IN);
}
else
dev_dbg(&dev->interface->dev,
"data format error - no EOF\n");
break;
case CMD_ACK:
dev_dbg(&dev->interface->dev, "%s ack: %c\n",
__func__, buf[1]);
wake_up_interruptible(&dev->waitq);
break;
}
retval = usb_submit_urb(dev->urb, GFP_ATOMIC);
if (retval) {
dev_err(&dev->interface->dev, "%s - usb_submit_urb failed: %d\n",
__func__, retval);
}
}
static int yurex_probe(struct usb_interface *interface, const struct usb_device_id *id)
{
struct usb_yurex *dev;
struct usb_host_interface *iface_desc;
struct usb_endpoint_descriptor *endpoint;
int retval = -ENOMEM;
DEFINE_WAIT(wait);
int res;
/* allocate memory for our device state and initialize it */
dev = kzalloc(sizeof(*dev), GFP_KERNEL);
if (!dev)
goto error;
kref_init(&dev->kref);
mutex_init(&dev->io_mutex);
spin_lock_init(&dev->lock);
init_waitqueue_head(&dev->waitq);
dev->udev = usb_get_dev(interface_to_usbdev(interface));
dev->interface = usb_get_intf(interface);
/* set up the endpoint information */
iface_desc = interface->cur_altsetting;
res = usb_find_int_in_endpoint(iface_desc, &endpoint);
if (res) {
dev_err(&interface->dev, "Could not find endpoints\n");
retval = res;
goto error;
}
dev->int_in_endpointAddr = endpoint->bEndpointAddress;
/* allocate control URB */
dev->cntl_urb = usb_alloc_urb(0, GFP_KERNEL);
if (!dev->cntl_urb)
goto error;
/* allocate buffer for control req */
dev->cntl_req = kmalloc(YUREX_BUF_SIZE, GFP_KERNEL);
if (!dev->cntl_req)
goto error;
/* allocate buffer for control msg */
dev->cntl_buffer = usb_alloc_coherent(dev->udev, YUREX_BUF_SIZE,
GFP_KERNEL,
&dev->cntl_urb->transfer_dma);
if (!dev->cntl_buffer) {
dev_err(&interface->dev, "Could not allocate cntl_buffer\n");
goto error;
}
/* configure control URB */
dev->cntl_req->bRequestType = USB_DIR_OUT | USB_TYPE_CLASS |
USB_RECIP_INTERFACE;
dev->cntl_req->bRequest = HID_REQ_SET_REPORT;
dev->cntl_req->wValue = cpu_to_le16((HID_OUTPUT_REPORT + 1) << 8);
dev->cntl_req->wIndex = cpu_to_le16(iface_desc->desc.bInterfaceNumber);
dev->cntl_req->wLength = cpu_to_le16(YUREX_BUF_SIZE);
usb_fill_control_urb(dev->cntl_urb, dev->udev,
usb_sndctrlpipe(dev->udev, 0),
(void *)dev->cntl_req, dev->cntl_buffer,
YUREX_BUF_SIZE, yurex_control_callback, dev);
dev->cntl_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
/* allocate interrupt URB */
dev->urb = usb_alloc_urb(0, GFP_KERNEL);
if (!dev->urb)
goto error;
/* allocate buffer for interrupt in */
dev->int_buffer = usb_alloc_coherent(dev->udev, YUREX_BUF_SIZE,
GFP_KERNEL, &dev->urb->transfer_dma);
if (!dev->int_buffer) {
dev_err(&interface->dev, "Could not allocate int_buffer\n");
goto error;
}
/* configure interrupt URB */
usb_fill_int_urb(dev->urb, dev->udev,
usb_rcvintpipe(dev->udev, dev->int_in_endpointAddr),
dev->int_buffer, YUREX_BUF_SIZE, yurex_interrupt,
dev, 1);
dev->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
if (usb_submit_urb(dev->urb, GFP_KERNEL)) {
retval = -EIO;
dev_err(&interface->dev, "Could not submitting URB\n");
goto error;
}
/* save our data pointer in this interface device */
usb_set_intfdata(interface, dev);
dev->bbu = -1;
/* we can register the device now, as it is ready */
retval = usb_register_dev(interface, &yurex_class);
if (retval) {
dev_err(&interface->dev,
"Not able to get a minor for this device.\n");
usb_set_intfdata(interface, NULL);
goto error;
}
dev_info(&interface->dev,
"USB YUREX device now attached to Yurex #%d\n",
interface->minor);
return 0;
error:
if (dev)
/* this frees allocated memory */
kref_put(&dev->kref, yurex_delete);
return retval;
}
static void yurex_disconnect(struct usb_interface *interface)
{
struct usb_yurex *dev;
int minor = interface->minor;
dev = usb_get_intfdata(interface);
usb_set_intfdata(interface, NULL);
/* give back our minor */
usb_deregister_dev(interface, &yurex_class);
/* prevent more I/O from starting */
usb_poison_urb(dev->urb);
usb_poison_urb(dev->cntl_urb);
mutex_lock(&dev->io_mutex);
dev->disconnected = 1;
mutex_unlock(&dev->io_mutex);
/* wakeup waiters */
kill_fasync(&dev->async_queue, SIGIO, POLL_IN);
wake_up_interruptible(&dev->waitq);
/* decrement our usage count */
kref_put(&dev->kref, yurex_delete);
dev_info(&interface->dev, "USB YUREX #%d now disconnected\n", minor);
}
static struct usb_driver yurex_driver = {
.name = "yurex",
.probe = yurex_probe,
.disconnect = yurex_disconnect,
.id_table = yurex_table,
};
static int yurex_fasync(int fd, struct file *file, int on)
{
struct usb_yurex *dev;
dev = file->private_data;
return fasync_helper(fd, file, on, &dev->async_queue);
}
static int yurex_open(struct inode *inode, struct file *file)
{
struct usb_yurex *dev;
struct usb_interface *interface;
int subminor;
int retval = 0;
subminor = iminor(inode);
interface = usb_find_interface(&yurex_driver, subminor);
if (!interface) {
printk(KERN_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;
}
/* increment our usage count for the device */
kref_get(&dev->kref);
/* save our object in the file's private structure */
mutex_lock(&dev->io_mutex);
file->private_data = dev;
mutex_unlock(&dev->io_mutex);
exit:
return retval;
}
static int yurex_release(struct inode *inode, struct file *file)
{
struct usb_yurex *dev;
dev = file->private_data;
if (dev == NULL)
return -ENODEV;
/* decrement the count on our device */
kref_put(&dev->kref, yurex_delete);
return 0;
}
static ssize_t yurex_read(struct file *file, char __user *buffer, size_t count,
loff_t *ppos)
{
struct usb_yurex *dev;
int len = 0;
char in_buffer[20];
unsigned long flags;
dev = file->private_data;
mutex_lock(&dev->io_mutex);
if (dev->disconnected) { /* already disconnected */
mutex_unlock(&dev->io_mutex);
return -ENODEV;
}
spin_lock_irqsave(&dev->lock, flags);
len = snprintf(in_buffer, 20, "%lld\n", dev->bbu);
spin_unlock_irqrestore(&dev->lock, flags);
mutex_unlock(&dev->io_mutex);
if (WARN_ON_ONCE(len >= sizeof(in_buffer)))
return -EIO;
return simple_read_from_buffer(buffer, count, ppos, in_buffer, len);
}
static ssize_t yurex_write(struct file *file, const char __user *user_buffer,
size_t count, loff_t *ppos)
{
struct usb_yurex *dev;
int i, set = 0, retval = 0;
char buffer[16 + 1];
char *data = buffer;
unsigned long long c, c2 = 0;
signed long timeout = 0;
DEFINE_WAIT(wait);
count = min(sizeof(buffer) - 1, count);
dev = file->private_data;
/* verify that we actually have some data to write */
if (count == 0)
goto error;
mutex_lock(&dev->io_mutex);
if (dev->disconnected) { /* already disconnected */
mutex_unlock(&dev->io_mutex);
retval = -ENODEV;
goto error;
}
if (copy_from_user(buffer, user_buffer, count)) {
mutex_unlock(&dev->io_mutex);
retval = -EFAULT;
goto error;
}
buffer[count] = 0;
memset(dev->cntl_buffer, CMD_PADDING, YUREX_BUF_SIZE);
switch (buffer[0]) {
case CMD_ANIMATE:
case CMD_LED:
dev->cntl_buffer[0] = buffer[0];
dev->cntl_buffer[1] = buffer[1];
dev->cntl_buffer[2] = CMD_EOF;
break;
case CMD_READ:
case CMD_VERSION:
dev->cntl_buffer[0] = buffer[0];
dev->cntl_buffer[1] = 0x00;
dev->cntl_buffer[2] = CMD_EOF;
break;
case CMD_SET:
data++;
/* FALL THROUGH */
case '0' ... '9':
set = 1;
c = c2 = simple_strtoull(data, NULL, 0);
dev->cntl_buffer[0] = CMD_SET;
for (i = 1; i < 6; i++) {
dev->cntl_buffer[i] = (c>>32) & 0xff;
c <<= 8;
}
buffer[6] = CMD_EOF;
break;
default:
mutex_unlock(&dev->io_mutex);
return -EINVAL;
}
/* send the data as the control msg */
prepare_to_wait(&dev->waitq, &wait, TASK_INTERRUPTIBLE);
dev_dbg(&dev->interface->dev, "%s - submit %c\n", __func__,
dev->cntl_buffer[0]);
retval = usb_submit_urb(dev->cntl_urb, GFP_KERNEL);
if (retval >= 0)
timeout = schedule_timeout(YUREX_WRITE_TIMEOUT);
finish_wait(&dev->waitq, &wait);
mutex_unlock(&dev->io_mutex);
if (retval < 0) {
dev_err(&dev->interface->dev,
"%s - failed to send bulk msg, error %d\n",
__func__, retval);
goto error;
}
if (set && timeout)
dev->bbu = c2;
return timeout ? count : -EIO;
error:
return retval;
}
static const struct file_operations yurex_fops = {
.owner = THIS_MODULE,
.read = yurex_read,
.write = yurex_write,
.open = yurex_open,
.release = yurex_release,
.fasync = yurex_fasync,
.llseek = default_llseek,
};
module_usb_driver(yurex_driver);
MODULE_LICENSE("GPL");