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|
// SPDX-License-Identifier: GPL-2.0+
/*
* LEGO USB Tower driver
*
* Copyright (C) 2003 David Glance <davidgsf@sourceforge.net>
* 2001-2004 Juergen Stuber <starblue@users.sourceforge.net>
*
* derived from USB Skeleton driver - 0.5
* Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
*
* History:
*
* 2001-10-13 - 0.1 js
* - first version
* 2001-11-03 - 0.2 js
* - simplified buffering, one-shot URBs for writing
* 2001-11-10 - 0.3 js
* - removed IOCTL (setting power/mode is more complicated, postponed)
* 2001-11-28 - 0.4 js
* - added vendor commands for mode of operation and power level in open
* 2001-12-04 - 0.5 js
* - set IR mode by default (by oversight 0.4 set VLL mode)
* 2002-01-11 - 0.5? pcchan
* - make read buffer reusable and work around bytes_to_write issue between
* uhci and legusbtower
* 2002-09-23 - 0.52 david (david@csse.uwa.edu.au)
* - imported into lejos project
* - changed wake_up to wake_up_interruptible
* - changed to use lego0 rather than tower0
* - changed dbg() to use __func__ rather than deprecated __func__
* 2003-01-12 - 0.53 david (david@csse.uwa.edu.au)
* - changed read and write to write everything or
* timeout (from a patch by Chris Riesen and Brett Thaeler driver)
* - added ioctl functionality to set timeouts
* 2003-07-18 - 0.54 davidgsf (david@csse.uwa.edu.au)
* - initial import into LegoUSB project
* - merge of existing LegoUSB.c driver
* 2003-07-18 - 0.56 davidgsf (david@csse.uwa.edu.au)
* - port to 2.6 style driver
* 2004-02-29 - 0.6 Juergen Stuber <starblue@users.sourceforge.net>
* - fix locking
* - unlink read URBs which are no longer needed
* - allow increased buffer size, eliminates need for timeout on write
* - have read URB running continuously
* - added poll
* - forbid seeking
* - added nonblocking I/O
* - changed back __func__ to __func__
* - read and log tower firmware version
* - reset tower on probe, avoids failure of first write
* 2004-03-09 - 0.7 Juergen Stuber <starblue@users.sourceforge.net>
* - timeout read now only after inactivity, shorten default accordingly
* 2004-03-11 - 0.8 Juergen Stuber <starblue@users.sourceforge.net>
* - log major, minor instead of possibly confusing device filename
* - whitespace cleanup
* 2004-03-12 - 0.9 Juergen Stuber <starblue@users.sourceforge.net>
* - normalize whitespace in debug messages
* - take care about endianness in control message responses
* 2004-03-13 - 0.91 Juergen Stuber <starblue@users.sourceforge.net>
* - make default intervals longer to accommodate current EHCI driver
* 2004-03-19 - 0.92 Juergen Stuber <starblue@users.sourceforge.net>
* - replaced atomic_t by memory barriers
* 2004-04-21 - 0.93 Juergen Stuber <starblue@users.sourceforge.net>
* - wait for completion of write urb in release (needed for remotecontrol)
* - corrected poll for write direction (missing negation)
* 2004-04-22 - 0.94 Juergen Stuber <starblue@users.sourceforge.net>
* - make device locking interruptible
* 2004-04-30 - 0.95 Juergen Stuber <starblue@users.sourceforge.net>
* - check for valid udev on resubmitting and unlinking urbs
* 2004-08-03 - 0.96 Juergen Stuber <starblue@users.sourceforge.net>
* - move reset into open to clean out spurious data
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/completion.h>
#include <linux/mutex.h>
#include <linux/uaccess.h>
#include <linux/usb.h>
#include <linux/poll.h>
#define DRIVER_AUTHOR "Juergen Stuber <starblue@sourceforge.net>"
#define DRIVER_DESC "LEGO USB Tower Driver"
/* The defaults are chosen to work with the latest versions of leJOS and NQC.
*/
/* Some legacy software likes to receive packets in one piece.
* In this case read_buffer_size should exceed the maximal packet length
* (417 for datalog uploads), and packet_timeout should be set.
*/
static int read_buffer_size = 480;
module_param(read_buffer_size, int, 0);
MODULE_PARM_DESC(read_buffer_size, "Read buffer size");
/* Some legacy software likes to send packets in one piece.
* In this case write_buffer_size should exceed the maximal packet length
* (417 for firmware and program downloads).
* A problem with long writes is that the following read may time out
* if the software is not prepared to wait long enough.
*/
static int write_buffer_size = 480;
module_param(write_buffer_size, int, 0);
MODULE_PARM_DESC(write_buffer_size, "Write buffer size");
/* Some legacy software expects reads to contain whole LASM packets.
* To achieve this, characters which arrive before a packet timeout
* occurs will be returned in a single read operation.
* A problem with long reads is that the software may time out
* if it is not prepared to wait long enough.
* The packet timeout should be greater than the time between the
* reception of subsequent characters, which should arrive about
* every 5ms for the standard 2400 baud.
* Set it to 0 to disable.
*/
static int packet_timeout = 50;
module_param(packet_timeout, int, 0);
MODULE_PARM_DESC(packet_timeout, "Packet timeout in ms");
/* Some legacy software expects blocking reads to time out.
* Timeout occurs after the specified time of read and write inactivity.
* Set it to 0 to disable.
*/
static int read_timeout = 200;
module_param(read_timeout, int, 0);
MODULE_PARM_DESC(read_timeout, "Read timeout in ms");
/* As of kernel version 2.6.4 ehci-hcd uses an
* "only one interrupt transfer per frame" shortcut
* to simplify the scheduling of periodic transfers.
* This conflicts with our standard 1ms intervals for in and out URBs.
* We use default intervals of 2ms for in and 8ms for out transfers,
* which is fast enough for 2400 baud and allows a small additional load.
* Increase the interval to allow more devices that do interrupt transfers,
* or set to 0 to use the standard interval from the endpoint descriptors.
*/
static int interrupt_in_interval = 2;
module_param(interrupt_in_interval, int, 0);
MODULE_PARM_DESC(interrupt_in_interval, "Interrupt in interval in ms");
static int interrupt_out_interval = 8;
module_param(interrupt_out_interval, int, 0);
MODULE_PARM_DESC(interrupt_out_interval, "Interrupt out interval in ms");
/* Define these values to match your device */
#define LEGO_USB_TOWER_VENDOR_ID 0x0694
#define LEGO_USB_TOWER_PRODUCT_ID 0x0001
/* Vendor requests */
#define LEGO_USB_TOWER_REQUEST_RESET 0x04
#define LEGO_USB_TOWER_REQUEST_GET_VERSION 0xFD
struct tower_reset_reply {
__le16 size;
__u8 err_code;
__u8 spare;
};
struct tower_get_version_reply {
__le16 size;
__u8 err_code;
__u8 spare;
__u8 major;
__u8 minor;
__le16 build_no;
};
/* table of devices that work with this driver */
static const struct usb_device_id tower_table[] = {
{ USB_DEVICE(LEGO_USB_TOWER_VENDOR_ID, LEGO_USB_TOWER_PRODUCT_ID) },
{ } /* Terminating entry */
};
MODULE_DEVICE_TABLE(usb, tower_table);
#define LEGO_USB_TOWER_MINOR_BASE 160
/* Structure to hold all of our device specific stuff */
struct lego_usb_tower {
struct mutex lock; /* locks this structure */
struct usb_device *udev; /* save off the usb device pointer */
unsigned char minor; /* the starting minor number for this device */
int open_count; /* number of times this port has been opened */
unsigned long disconnected:1;
char *read_buffer;
size_t read_buffer_length; /* this much came in */
size_t read_packet_length; /* this much will be returned on read */
spinlock_t read_buffer_lock;
int packet_timeout_jiffies;
unsigned long read_last_arrival;
wait_queue_head_t read_wait;
wait_queue_head_t write_wait;
char *interrupt_in_buffer;
struct usb_endpoint_descriptor *interrupt_in_endpoint;
struct urb *interrupt_in_urb;
int interrupt_in_interval;
int interrupt_in_done;
char *interrupt_out_buffer;
struct usb_endpoint_descriptor *interrupt_out_endpoint;
struct urb *interrupt_out_urb;
int interrupt_out_interval;
int interrupt_out_busy;
};
/* local function prototypes */
static ssize_t tower_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos);
static ssize_t tower_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos);
static inline void tower_delete(struct lego_usb_tower *dev);
static int tower_open(struct inode *inode, struct file *file);
static int tower_release(struct inode *inode, struct file *file);
static __poll_t tower_poll(struct file *file, poll_table *wait);
static loff_t tower_llseek(struct file *file, loff_t off, int whence);
static void tower_check_for_read_packet(struct lego_usb_tower *dev);
static void tower_interrupt_in_callback(struct urb *urb);
static void tower_interrupt_out_callback(struct urb *urb);
static int tower_probe(struct usb_interface *interface, const struct usb_device_id *
|