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WSL2-Linux-Kernel/drivers/usb/serial/whiteheat.c

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44 KiB
C
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/*
* USB ConnectTech WhiteHEAT driver
*
* Copyright (C) 2002
* Connect Tech Inc.
*
* Copyright (C) 1999 - 2001
* 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; either version 2 of the License, or
* (at your option) any later version.
*
* See Documentation/usb/usb-serial.txt for more information on using this driver
*
* (10/09/2002) Stuart MacDonald (stuartm@connecttech.com)
* Upgrade to full working driver
*
* (05/30/2001) gkh
* switched from using spinlock to a semaphore, which fixes lots of problems.
*
* (04/08/2001) gb
* Identify version on module load.
*
* 2001_Mar_19 gkh
* Fixed MOD_INC and MOD_DEC logic, the ability to open a port more
* than once, and the got the proper usb_device_id table entries so
* the driver works again.
*
* (11/01/2000) Adam J. Richter
* usb_device_id table support
*
* (10/05/2000) gkh
* Fixed bug with urb->dev not being set properly, now that the usb
* core needs it.
*
* (10/03/2000) smd
* firmware is improved to guard against crap sent to device
* firmware now replies CMD_FAILURE on bad things
* read_callback fix you provided for private info struct
* command_finished now indicates success or fail
* setup_port struct now packed to avoid gcc padding
* firmware uses 1 based port numbering, driver now handles that
*
* (09/11/2000) gkh
* Removed DEBUG #ifdefs with call to usb_serial_debug_data
*
* (07/19/2000) gkh
* Added module_init and module_exit functions to handle the fact that this
* driver is a loadable module now.
* Fixed bug with port->minor that was found by Al Borchers
*
* (07/04/2000) gkh
* Added support for port settings. Baud rate can now be changed. Line signals
* are not transferred to and from the tty layer yet, but things seem to be
* working well now.
*
* (05/04/2000) gkh
* First cut at open and close commands. Data can flow through the ports at
* default speeds now.
*
* (03/26/2000) gkh
* Split driver up into device specific pieces.
*
*/
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/tty.h>
#include <linux/tty_driver.h>
#include <linux/tty_flip.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <asm/uaccess.h>
#include <asm/termbits.h>
#include <linux/usb.h>
#include <linux/serial_reg.h>
#include <linux/serial.h>
#include <linux/usb/serial.h>
#include "whiteheat_fw.h" /* firmware for the ConnectTech WhiteHEAT device */
#include "whiteheat.h" /* WhiteHEAT specific commands */
static int debug;
#ifndef CMSPAR
#define CMSPAR 0
#endif
/*
* Version Information
*/
#define DRIVER_VERSION "v2.0"
#define DRIVER_AUTHOR "Greg Kroah-Hartman <greg@kroah.com>, Stuart MacDonald <stuartm@connecttech.com>"
#define DRIVER_DESC "USB ConnectTech WhiteHEAT driver"
#define CONNECT_TECH_VENDOR_ID 0x0710
#define CONNECT_TECH_FAKE_WHITE_HEAT_ID 0x0001
#define CONNECT_TECH_WHITE_HEAT_ID 0x8001
/*
ID tables for whiteheat are unusual, because we want to different
things for different versions of the device. Eventually, this
will be doable from a single table. But, for now, we define two
separate ID tables, and then a third table that combines them
just for the purpose of exporting the autoloading information.
*/
static struct usb_device_id id_table_std [] = {
{ USB_DEVICE(CONNECT_TECH_VENDOR_ID, CONNECT_TECH_WHITE_HEAT_ID) },
{ } /* Terminating entry */
};
static struct usb_device_id id_table_prerenumeration [] = {
{ USB_DEVICE(CONNECT_TECH_VENDOR_ID, CONNECT_TECH_FAKE_WHITE_HEAT_ID) },
{ } /* Terminating entry */
};
static struct usb_device_id id_table_combined [] = {
{ USB_DEVICE(CONNECT_TECH_VENDOR_ID, CONNECT_TECH_WHITE_HEAT_ID) },
{ USB_DEVICE(CONNECT_TECH_VENDOR_ID, CONNECT_TECH_FAKE_WHITE_HEAT_ID) },
{ } /* Terminating entry */
};
MODULE_DEVICE_TABLE (usb, id_table_combined);
static struct usb_driver whiteheat_driver = {
.name = "whiteheat",
.probe = usb_serial_probe,
.disconnect = usb_serial_disconnect,
.id_table = id_table_combined,
.no_dynamic_id = 1,
};
/* function prototypes for the Connect Tech WhiteHEAT prerenumeration device */
static int whiteheat_firmware_download (struct usb_serial *serial, const struct usb_device_id *id);
static int whiteheat_firmware_attach (struct usb_serial *serial);
/* function prototypes for the Connect Tech WhiteHEAT serial converter */
static int whiteheat_attach (struct usb_serial *serial);
static void whiteheat_shutdown (struct usb_serial *serial);
static int whiteheat_open (struct usb_serial_port *port, struct file *filp);
static void whiteheat_close (struct usb_serial_port *port, struct file *filp);
static int whiteheat_write (struct usb_serial_port *port, const unsigned char *buf, int count);
static int whiteheat_write_room (struct usb_serial_port *port);
static int whiteheat_ioctl (struct usb_serial_port *port, struct file * file, unsigned int cmd, unsigned long arg);
static void whiteheat_set_termios (struct usb_serial_port *port, struct ktermios * old);
static int whiteheat_tiocmget (struct usb_serial_port *port, struct file *file);
static int whiteheat_tiocmset (struct usb_serial_port *port, struct file *file, unsigned int set, unsigned int clear);
static void whiteheat_break_ctl (struct usb_serial_port *port, int break_state);
static int whiteheat_chars_in_buffer (struct usb_serial_port *port);
static void whiteheat_throttle (struct usb_serial_port *port);
static void whiteheat_unthrottle (struct usb_serial_port *port);
static void whiteheat_read_callback (struct urb *urb);
static void whiteheat_write_callback (struct urb *urb);
static struct usb_serial_driver whiteheat_fake_device = {
.driver = {
.owner = THIS_MODULE,
.name = "whiteheatnofirm",
},
.description = "Connect Tech - WhiteHEAT - (prerenumeration)",
.usb_driver = &whiteheat_driver,
.id_table = id_table_prerenumeration,
.num_interrupt_in = NUM_DONT_CARE,
.num_bulk_in = NUM_DONT_CARE,
.num_bulk_out = NUM_DONT_CARE,
.num_ports = 1,
.probe = whiteheat_firmware_download,
.attach = whiteheat_firmware_attach,
};
static struct usb_serial_driver whiteheat_device = {
.driver = {
.owner = THIS_MODULE,
.name = "whiteheat",
},
.description = "Connect Tech - WhiteHEAT",
.usb_driver = &whiteheat_driver,
.id_table = id_table_std,
.num_interrupt_in = NUM_DONT_CARE,
.num_bulk_in = NUM_DONT_CARE,
.num_bulk_out = NUM_DONT_CARE,
.num_ports = 4,
.attach = whiteheat_attach,
.shutdown = whiteheat_shutdown,
.open = whiteheat_open,
.close = whiteheat_close,
.write = whiteheat_write,
.write_room = whiteheat_write_room,
.ioctl = whiteheat_ioctl,
.set_termios = whiteheat_set_termios,
.break_ctl = whiteheat_break_ctl,
.tiocmget = whiteheat_tiocmget,
.tiocmset = whiteheat_tiocmset,
.chars_in_buffer = whiteheat_chars_in_buffer,
.throttle = whiteheat_throttle,
.unthrottle = whiteheat_unthrottle,
.read_bulk_callback = whiteheat_read_callback,
.write_bulk_callback = whiteheat_write_callback,
};
struct whiteheat_command_private {
spinlock_t lock;
__u8 port_running;
__u8 command_finished;
wait_queue_head_t wait_command; /* for handling sleeping while waiting for a command to finish */
__u8 result_buffer[64];
};
#define THROTTLED 0x01
#define ACTUALLY_THROTTLED 0x02
static int urb_pool_size = 8;
struct whiteheat_urb_wrap {
struct list_head list;
struct urb *urb;
};
struct whiteheat_private {
spinlock_t lock;
__u8 flags;
__u8 mcr;
struct list_head rx_urbs_free;
struct list_head rx_urbs_submitted;
struct list_head rx_urb_q;
struct work_struct rx_work;
struct usb_serial_port *port;
struct list_head tx_urbs_free;
struct list_head tx_urbs_submitted;
};
/* local function prototypes */
static int start_command_port(struct usb_serial *serial);
static void stop_command_port(struct usb_serial *serial);
static void command_port_write_callback(struct urb *urb);
static void command_port_read_callback(struct urb *urb);
static int start_port_read(struct usb_serial_port *port);
static struct whiteheat_urb_wrap *urb_to_wrap(struct urb *urb, struct list_head *head);
static struct list_head *list_first(struct list_head *head);
static void rx_data_softint(struct work_struct *work);
static int firm_send_command(struct usb_serial_port *port, __u8 command, __u8 *data, __u8 datasize);
static int firm_open(struct usb_serial_port *port);
static int firm_close(struct usb_serial_port *port);
static int firm_setup_port(struct usb_serial_port *port);
static int firm_set_rts(struct usb_serial_port *port, __u8 onoff);
static int firm_set_dtr(struct usb_serial_port *port, __u8 onoff);
static int firm_set_break(struct usb_serial_port *port, __u8 onoff);
static int firm_purge(struct usb_serial_port *port, __u8 rxtx);
static int firm_get_dtr_rts(struct usb_serial_port *port);
static int firm_report_tx_done(struct usb_serial_port *port);
#define COMMAND_PORT 4
#define COMMAND_TIMEOUT (2*HZ) /* 2 second timeout for a command */
#define COMMAND_TIMEOUT_MS 2000
#define CLOSING_DELAY (30 * HZ)
/*****************************************************************************
* Connect Tech's White Heat prerenumeration driver functions
*****************************************************************************/
/* steps to download the firmware to the WhiteHEAT device:
- hold the reset (by writing to the reset bit of the CPUCS register)
- download the VEND_AX.HEX file to the chip using VENDOR_REQUEST-ANCHOR_LOAD
- release the reset (by writing to the CPUCS register)
- download the WH.HEX file for all addresses greater than 0x1b3f using
VENDOR_REQUEST-ANCHOR_EXTERNAL_RAM_LOAD
- hold the reset
- download the WH.HEX file for all addresses less than 0x1b40 using
VENDOR_REQUEST_ANCHOR_LOAD
- release the reset
- device renumerated itself and comes up as new device id with all
firmware download completed.
*/
static int whiteheat_firmware_download (struct usb_serial *serial, const struct usb_device_id *id)
{
int response;
const struct whiteheat_hex_record *record;
dbg("%s", __FUNCTION__);
response = ezusb_set_reset (serial, 1);
record = &whiteheat_loader[0];
while (record->address != 0xffff) {
response = ezusb_writememory (serial, record->address,
(unsigned char *)record->data, record->data_size, 0xa0);
if (response < 0) {
err("%s - ezusb_writememory failed for loader (%d %04X %p %d)",
__FUNCTION__, response, record->address, record->data, record->data_size);
break;
}
++record;
}
response = ezusb_set_reset (serial, 0);
record = &whiteheat_firmware[0];
while (record->address < 0x1b40) {
++record;
}
while (record->address != 0xffff) {
response = ezusb_writememory (serial, record->address,
(unsigned char *)record->data, record->data_size, 0xa3);
if (response < 0) {
err("%s - ezusb_writememory failed for first firmware step (%d %04X %p %d)",
__FUNCTION__, response, record->address, record->data, record->data_size);
break;
}
++record;
}
response = ezusb_set_reset (serial, 1);
record = &whiteheat_firmware[0];
while (record->address < 0x1b40) {
response = ezusb_writememory (serial, record->address,
(unsigned char *)record->data, record->data_size, 0xa0);
if (response < 0) {
err("%s - ezusb_writememory failed for second firmware step (%d %04X %p %d)",
__FUNCTION__, response, record->address, record->data, record->data_size);
break;
}
++record;
}
response = ezusb_set_reset (serial, 0);
return 0;
}
static int whiteheat_firmware_attach (struct usb_serial *serial)
{
/* We want this device to fail to have a driver assigned to it */
return 1;
}
/*****************************************************************************
* Connect Tech's White Heat serial driver functions
*****************************************************************************/
static int whiteheat_attach (struct usb_serial *serial)
{
struct usb_serial_port *command_port;
struct whiteheat_command_private *command_info;
struct usb_serial_port *port;
struct whiteheat_private *info;
struct whiteheat_hw_info *hw_info;
int pipe;
int ret;
int alen;
__u8 *command;
__u8 *result;
int i;
int j;
struct urb *urb;
int buf_size;
struct whiteheat_urb_wrap *wrap;
struct list_head *tmp;
command_port = serial->port[COMMAND_PORT];
pipe = usb_sndbulkpipe (serial->dev, command_port->bulk_out_endpointAddress);
command = kmalloc(2, GFP_KERNEL);
if (!command)
goto no_command_buffer;
command[0] = WHITEHEAT_GET_HW_INFO;
command[1] = 0;
result = kmalloc(sizeof(*hw_info) + 1, GFP_KERNEL);
if (!result)
goto no_result_buffer;
/*
* When the module is reloaded the firmware is still there and
* the endpoints are still in the usb core unchanged. This is the
* unlinking bug in disguise. Same for the call below.
*/
usb_clear_halt(serial->dev, pipe);
ret = usb_bulk_msg (serial->dev, pipe, command, 2, &alen, COMMAND_TIMEOUT_MS);
if (ret) {
err("%s: Couldn't send command [%d]", serial->type->description, ret);
goto no_firmware;
} else if (alen != 2) {
err("%s: Send command incomplete [%d]", serial->type->description, alen);
goto no_firmware;
}
pipe = usb_rcvbulkpipe (serial->dev, command_port->bulk_in_endpointAddress);
/* See the comment on the usb_clear_halt() above */
usb_clear_halt(serial->dev, pipe);
ret = usb_bulk_msg (serial->dev, pipe, result, sizeof(*hw_info) + 1, &alen, COMMAND_TIMEOUT_MS);
if (ret) {
err("%s: Couldn't get results [%d]", serial->type->description, ret);
goto no_firmware;
} else if (alen != sizeof(*hw_info) + 1) {
err("%s: Get results incomplete [%d]", serial->type->description, alen);
goto no_firmware;
} else if (result[0] != command[0]) {
err("%s: Command failed [%d]", serial->type->description, result[0]);
goto no_firmware;
}
hw_info = (struct whiteheat_hw_info *)&result[1];
info("%s: Driver %s: Firmware v%d.%02d", serial->type->description,
DRIVER_VERSION, hw_info->sw_major_rev, hw_info->sw_minor_rev);
for (i = 0; i < serial->num_ports; i++) {
port = serial->port[i];
info = kmalloc(sizeof(struct whiteheat_private), GFP_KERNEL);
if (info == NULL) {
err("%s: Out of memory for port structures\n", serial->type->description);
goto no_private;
}
spin_lock_init(&info->lock);
info->flags = 0;
info->mcr = 0;
INIT_WORK(&info->rx_work, rx_data_softint);
info->port = port;
INIT_LIST_HEAD(&info->rx_urbs_free);
INIT_LIST_HEAD(&info->rx_urbs_submitted);
INIT_LIST_HEAD(&info->rx_urb_q);
INIT_LIST_HEAD(&info->tx_urbs_free);
INIT_LIST_HEAD(&info->tx_urbs_submitted);
for (j = 0; j < urb_pool_size; j++) {
urb = usb_alloc_urb(0, GFP_KERNEL);
if (!urb) {
err("No free urbs available");
goto no_rx_urb;
}
buf_size = port->read_urb->transfer_buffer_length;
urb->transfer_buffer = kmalloc(buf_size, GFP_KERNEL);
if (!urb->transfer_buffer) {
err("Couldn't allocate urb buffer");
goto no_rx_buf;
}
wrap = kmalloc(sizeof(*wrap), GFP_KERNEL);
if (!wrap) {
err("Couldn't allocate urb wrapper");
goto no_rx_wrap;
}
usb_fill_bulk_urb(urb, serial->dev,
usb_rcvbulkpipe(serial->dev,
port->bulk_in_endpointAddress),
urb->transfer_buffer, buf_size,
whiteheat_read_callback, port);
wrap->urb = urb;
list_add(&wrap->list, &info->rx_urbs_free);
urb = usb_alloc_urb(0, GFP_KERNEL);
if (!urb) {
err("No free urbs available");
goto no_tx_urb;
}
buf_size = port->write_urb->transfer_buffer_length;
urb->transfer_buffer = kmalloc(buf_size, GFP_KERNEL);
if (!urb->transfer_buffer) {
err("Couldn't allocate urb buffer");
goto no_tx_buf;
}
wrap = kmalloc(sizeof(*wrap), GFP_KERNEL);
if (!wrap) {
err("Couldn't allocate urb wrapper");
goto no_tx_wrap;
}
usb_fill_bulk_urb(urb, serial->dev,
usb_sndbulkpipe(serial->dev,
port->bulk_out_endpointAddress),
urb->transfer_buffer, buf_size,
whiteheat_write_callback, port);
wrap->urb = urb;
list_add(&wrap->list, &info->tx_urbs_free);
}
usb_set_serial_port_data(port, info);
}
command_info = kmalloc(sizeof(struct whiteheat_command_private), GFP_KERNEL);
if (command_info == NULL) {
err("%s: Out of memory for port structures\n", serial->type->description);
goto no_command_private;
}
spin_lock_init(&command_info->lock);
command_info->port_running = 0;
init_waitqueue_head(&command_info->wait_command);
usb_set_serial_port_data(command_port, command_info);
command_port->write_urb->complete = command_port_write_callback;
command_port->read_urb->complete = command_port_read_callback;
kfree(result);
kfree(command);
return 0;
no_firmware:
/* Firmware likely not running */
err("%s: Unable to retrieve firmware version, try replugging\n", serial->type->description);
err("%s: If the firmware is not running (status led not blinking)\n", serial->type->description);
err("%s: please contact support@connecttech.com\n", serial->type->description);
kfree(result);
return -ENODEV;
no_command_private:
for (i = serial->num_ports - 1; i >= 0; i--) {
port = serial->port[i];
info = usb_get_serial_port_data(port);
for (j = urb_pool_size - 1; j >= 0; j--) {
tmp = list_first(&info->tx_urbs_free);
list_del(tmp);
wrap = list_entry(tmp, struct whiteheat_urb_wrap, list);
urb = wrap->urb;
kfree(wrap);
no_tx_wrap:
kfree(urb->transfer_buffer);
no_tx_buf:
usb_free_urb(urb);
no_tx_urb:
tmp = list_first(&info->rx_urbs_free);
list_del(tmp);
wrap = list_entry(tmp, struct whiteheat_urb_wrap, list);
urb = wrap->urb;
kfree(wrap);
no_rx_wrap:
kfree(urb->transfer_buffer);
no_rx_buf:
usb_free_urb(urb);
no_rx_urb:
;
}
kfree(info);
no_private:
;
}
kfree(result);
no_result_buffer:
kfree(command);
no_command_buffer:
return -ENOMEM;
}
static void whiteheat_shutdown (struct usb_serial *serial)
{
struct usb_serial_port *command_port;
struct usb_serial_port *port;
struct whiteheat_private *info;
struct whiteheat_urb_wrap *wrap;
struct urb *urb;
struct list_head *tmp;
struct list_head *tmp2;
int i;
dbg("%s", __FUNCTION__);
/* free up our private data for our command port */
command_port = serial->port[COMMAND_PORT];
kfree (usb_get_serial_port_data(command_port));
for (i = 0; i < serial->num_ports; i++) {
port = serial->port[i];
info = usb_get_serial_port_data(port);
list_for_each_safe(tmp, tmp2, &info->rx_urbs_free) {
list_del(tmp);
wrap = list_entry(tmp, struct whiteheat_urb_wrap, list);
urb = wrap->urb;
kfree(wrap);
kfree(urb->transfer_buffer);
usb_free_urb(urb);
}
list_for_each_safe(tmp, tmp2, &info->tx_urbs_free) {
list_del(tmp);
wrap = list_entry(tmp, struct whiteheat_urb_wrap, list);
urb = wrap->urb;
kfree(wrap);
kfree(urb->transfer_buffer);
usb_free_urb(urb);
}
kfree(info);
}
return;
}
static int whiteheat_open (struct usb_serial_port *port, struct file *filp)
{
int retval = 0;
struct ktermios old_term;
dbg("%s - port %d", __FUNCTION__, port->number);
retval = start_command_port(port->serial);
if (retval)
goto exit;
if (port->tty)
port->tty->low_latency = 1;
/* send an open port command */
retval = firm_open(port);
if (retval) {
stop_command_port(port->serial);
goto exit;
}
retval = firm_purge(port, WHITEHEAT_PURGE_RX | WHITEHEAT_PURGE_TX);
if (retval) {
firm_close(port);
stop_command_port(port->serial);
goto exit;
}
old_term.c_cflag = ~port->tty->termios->c_cflag;
old_term.c_iflag = ~port->tty->termios->c_iflag;
whiteheat_set_termios(port, &old_term);
/* Work around HCD bugs */
usb_clear_halt(port->serial->dev, port->read_urb->pipe);
usb_clear_halt(port->serial->dev, port->write_urb->pipe);
/* Start reading from the device */
retval = start_port_read(port);
if (retval) {
err("%s - failed submitting read urb, error %d", __FUNCTION__, retval);
firm_close(port);
stop_command_port(port->serial);
goto exit;
}
exit:
dbg("%s - exit, retval = %d", __FUNCTION__, retval);
return retval;
}
static void whiteheat_close(struct usb_serial_port *port, struct file * filp)
{
struct whiteheat_private *info = usb_get_serial_port_data(port);
struct whiteheat_urb_wrap *wrap;
struct urb *urb;
struct list_head *tmp;
struct list_head *tmp2;
unsigned long flags;
dbg("%s - port %d", __FUNCTION__, port->number);
/* filp is NULL when called from usb_serial_disconnect */
if (filp && (tty_hung_up_p(filp))) {
return;
}
port->tty->closing = 1;
/*
* Not currently in use; tty_wait_until_sent() calls
* serial_chars_in_buffer() which deadlocks on the second semaphore
* acquisition. This should be fixed at some point. Greg's been
* notified.
if ((filp->f_flags & (O_NDELAY | O_NONBLOCK)) == 0) {
tty_wait_until_sent(port->tty, CLOSING_DELAY);
}
*/
if (port->tty->driver->flush_buffer)
port->tty->driver->flush_buffer(port->tty);
tty_ldisc_flush(port->tty);
firm_report_tx_done(port);
firm_close(port);
/* shutdown our bulk reads and writes */
spin_lock_irqsave(&info->lock, flags);
list_for_each_safe(tmp, tmp2, &info->rx_urbs_submitted) {
wrap = list_entry(tmp, struct whiteheat_urb_wrap, list);
urb = wrap->urb;
usb_kill_urb(urb);
list_move(tmp, &info->rx_urbs_free);
}
list_for_each_safe(tmp, tmp2, &info->rx_urb_q)
list_move(tmp, &info->rx_urbs_free);
list_for_each_safe(tmp, tmp2, &info->tx_urbs_submitted) {
wrap = list_entry(tmp, struct whiteheat_urb_wrap, list);
urb = wrap->urb;
usb_kill_urb(urb);
list_move(tmp, &info->tx_urbs_free);
}
spin_unlock_irqrestore(&info->lock, flags);
stop_command_port(port->serial);
port->tty->closing = 0;
}
static int whiteheat_write(struct usb_serial_port *port, const unsigned char *buf, int count)
{
struct usb_serial *serial = port->serial;
struct whiteheat_private *info = usb_get_serial_port_data(port);
struct whiteheat_urb_wrap *wrap;
struct urb *urb;
int result;
int bytes;
int sent = 0;
unsigned long flags;
struct list_head *tmp;
dbg("%s - port %d", __FUNCTION__, port->number);
if (count == 0) {
dbg("%s - write request of 0 bytes", __FUNCTION__);
return (0);
}
while (count) {
spin_lock_irqsave(&info->lock, flags);
if (list_empty(&info->tx_urbs_free)) {
spin_unlock_irqrestore(&info->lock, flags);
break;
}
tmp = list_first(&info->tx_urbs_free);
list_del(tmp);
spin_unlock_irqrestore(&info->lock, flags);
wrap = list_entry(tmp, struct whiteheat_urb_wrap, list);
urb = wrap->urb;
bytes = (count > port->bulk_out_size) ? port->bulk_out_size : count;
memcpy (urb->transfer_buffer, buf + sent, bytes);
usb_serial_debug_data(debug, &port->dev, __FUNCTION__, bytes, urb->transfer_buffer);
urb->dev = serial->dev;
urb->transfer_buffer_length = bytes;
result = usb_submit_urb(urb, GFP_ATOMIC);
if (result) {
err("%s - failed submitting write urb, error %d", __FUNCTION__, result);
sent = result;
spin_lock_irqsave(&info->lock, flags);
list_add(tmp, &info->tx_urbs_free);
spin_unlock_irqrestore(&info->lock, flags);
break;
} else {
sent += bytes;
count -= bytes;
spin_lock_irqsave(&info->lock, flags);
list_add(tmp, &info->tx_urbs_submitted);
spin_unlock_irqrestore(&info->lock, flags);
}
}
return sent;
}
static int whiteheat_write_room(struct usb_serial_port *port)
{
struct whiteheat_private *info = usb_get_serial_port_data(port);
struct list_head *tmp;
int room = 0;
unsigned long flags;
dbg("%s - port %d", __FUNCTION__, port->number);
spin_lock_irqsave(&info->lock, flags);
list_for_each(tmp, &info->tx_urbs_free)
room++;
spin_unlock_irqrestore(&info->lock, flags);
room *= port->bulk_out_size;
dbg("%s - returns %d", __FUNCTION__, room);
return (room);
}
static int whiteheat_tiocmget (struct usb_serial_port *port, struct file *file)
{
struct whiteheat_private *info = usb_get_serial_port_data(port);
unsigned int modem_signals = 0;
dbg("%s - port %d", __FUNCTION__, port->number);
firm_get_dtr_rts(port);
if (info->mcr & UART_MCR_DTR)
modem_signals |= TIOCM_DTR;
if (info->mcr & UART_MCR_RTS)
modem_signals |= TIOCM_RTS;
return modem_signals;
}
static int whiteheat_tiocmset (struct usb_serial_port *port, struct file *file,
unsigned int set, unsigned int clear)
{
struct whiteheat_private *info = usb_get_serial_port_data(port);
dbg("%s - port %d", __FUNCTION__, port->number);
if (set & TIOCM_RTS)
info->mcr |= UART_MCR_RTS;
if (set & TIOCM_DTR)
info->mcr |= UART_MCR_DTR;
if (clear & TIOCM_RTS)
info->mcr &= ~UART_MCR_RTS;
if (clear & TIOCM_DTR)
info->mcr &= ~UART_MCR_DTR;
firm_set_dtr(port, info->mcr & UART_MCR_DTR);
firm_set_rts(port, info->mcr & UART_MCR_RTS);
return 0;
}
static int whiteheat_ioctl (struct usb_serial_port *port, struct file * file, unsigned int cmd, unsigned long arg)
{
struct serial_struct serstruct;
void __user *user_arg = (void __user *)arg;
dbg("%s - port %d, cmd 0x%.4x", __FUNCTION__, port->number, cmd);
switch (cmd) {
case TIOCGSERIAL:
memset(&serstruct, 0, sizeof(serstruct));
serstruct.type = PORT_16654;
serstruct.line = port->serial->minor;
serstruct.port = port->number;
serstruct.flags = ASYNC_SKIP_TEST | ASYNC_AUTO_IRQ;
serstruct.xmit_fifo_size = port->bulk_out_size;
serstruct.custom_divisor = 0;
serstruct.baud_base = 460800;
serstruct.close_delay = CLOSING_DELAY;
serstruct.closing_wait = CLOSING_DELAY;
if (copy_to_user(user_arg, &serstruct, sizeof(serstruct)))
return -EFAULT;
break;
case TIOCSSERIAL:
if (copy_from_user(&serstruct, user_arg, sizeof(serstruct)))
return -EFAULT;
/*
* For now this is ignored. dip sets the ASYNC_[V]HI flags
* but this isn't used by us at all. Maybe someone somewhere
* will need the custom_divisor setting.
*/
break;
default:
break;
}
return -ENOIOCTLCMD;
}
static void whiteheat_set_termios (struct usb_serial_port *port, struct ktermios *old_termios)
{
dbg("%s -port %d", __FUNCTION__, port->number);
if ((!port->tty) || (!port->tty->termios)) {
dbg("%s - no tty structures", __FUNCTION__);
goto exit;
}
/* check that they really want us to change something */
if (old_termios) {
if ((port->tty->termios->c_cflag == old_termios->c_cflag) &&
(port->tty->termios->c_iflag == old_termios->c_iflag)) {
dbg("%s - nothing to change...", __FUNCTION__);
goto exit;
}
}
firm_setup_port(port);
exit:
return;
}
static void whiteheat_break_ctl(struct usb_serial_port *port, int break_state) {
firm_set_break(port, break_state);
}
static int whiteheat_chars_in_buffer(struct usb_serial_port *port)
{
struct whiteheat_private *info = usb_get_serial_port_data(port);
struct list_head *tmp;
struct whiteheat_urb_wrap *wrap;
int chars = 0;
unsigned long flags;
dbg("%s - port %d", __FUNCTION__, port->number);
spin_lock_irqsave(&info->lock, flags);
list_for_each(tmp, &info->tx_urbs_submitted) {
wrap = list_entry(tmp, struct whiteheat_urb_wrap, list);
chars += wrap->urb->transfer_buffer_length;
}
spin_unlock_irqrestore(&info->lock, flags);
dbg ("%s - returns %d", __FUNCTION__, chars);
return (chars);
}
static void whiteheat_throttle (struct usb_serial_port *port)
{
struct whiteheat_private *info = usb_get_serial_port_data(port);
unsigned long flags;
dbg("%s - port %d", __FUNCTION__, port->number);
spin_lock_irqsave(&info->lock, flags);
info->flags |= THROTTLED;
spin_unlock_irqrestore(&info->lock, flags);
return;
}
static void whiteheat_unthrottle (struct usb_serial_port *port)
{
struct whiteheat_private *info = usb_get_serial_port_data(port);
int actually_throttled;
unsigned long flags;
dbg("%s - port %d", __FUNCTION__, port->number);
spin_lock_irqsave(&info->lock, flags);
actually_throttled = info->flags & ACTUALLY_THROTTLED;
info->flags &= ~(THROTTLED | ACTUALLY_THROTTLED);
spin_unlock_irqrestore(&info->lock, flags);
if (actually_throttled)
rx_data_softint(&info->rx_work);
return;
}
/*****************************************************************************
* Connect Tech's White Heat callback routines
*****************************************************************************/
static void command_port_write_callback (struct urb *urb)
{
dbg("%s", __FUNCTION__);
if (urb->status) {
dbg ("nonzero urb status: %d", urb->status);
return;
}
}
static void command_port_read_callback (struct urb *urb)
{
struct usb_serial_port *command_port = (struct usb_serial_port *)urb->context;
struct whiteheat_command_private *command_info;
unsigned char *data = urb->transfer_buffer;
int result;
unsigned long flags;
dbg("%s", __FUNCTION__);
if (urb->status) {
dbg("%s - nonzero urb status: %d", __FUNCTION__, urb->status);
return;
}
usb_serial_debug_data(debug, &command_port->dev, __FUNCTION__, urb->actual_length, data);
command_info = usb_get_serial_port_data(command_port);
if (!command_info) {
dbg ("%s - command_info is NULL, exiting.", __FUNCTION__);
return;
}
spin_lock_irqsave(&command_info->lock, flags);
if (data[0] == WHITEHEAT_CMD_COMPLETE) {
command_info->command_finished = WHITEHEAT_CMD_COMPLETE;
wake_up_interruptible(&command_info->wait_command);
} else if (data[0] == WHITEHEAT_CMD_FAILURE) {
command_info->command_finished = WHITEHEAT_CMD_FAILURE;
wake_up_interruptible(&command_info->wait_command);
} else if (data[0] == WHITEHEAT_EVENT) {
/* These are unsolicited reports from the firmware, hence no waiting command to wakeup */
dbg("%s - event received", __FUNCTION__);
} else if (data[0] == WHITEHEAT_GET_DTR_RTS) {
memcpy(command_info->result_buffer, &data[1], urb->actual_length - 1);
command_info->command_finished = WHITEHEAT_CMD_COMPLETE;
wake_up_interruptible(&command_info->wait_command);
} else {
dbg("%s - bad reply from firmware", __FUNCTION__);
}
/* Continue trying to always read */
command_port->read_urb->dev = command_port->serial->dev;
result = usb_submit_urb(command_port->read_urb, GFP_ATOMIC);
spin_unlock_irqrestore(&command_info->lock, flags);
if (result)
dbg("%s - failed resubmitting read urb, error %d", __FUNCTION__, result);
}
static void whiteheat_read_callback(struct urb *urb)
{
struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
struct whiteheat_urb_wrap *wrap;
unsigned char *data = urb->transfer_buffer;
struct whiteheat_private *info = usb_get_serial_port_data(port);
dbg("%s - port %d", __FUNCTION__, port->number);
spin_lock(&info->lock);
wrap = urb_to_wrap(urb, &info->rx_urbs_submitted);
if (!wrap) {
spin_unlock(&info->lock);
err("%s - Not my urb!", __FUNCTION__);
return;
}
list_del(&wrap->list);
spin_unlock(&info->lock);
if (urb->status) {
dbg("%s - nonzero read bulk status received: %d", __FUNCTION__, urb->status);
spin_lock(&info->lock);
list_add(&wrap->list, &info->rx_urbs_free);
spin_unlock(&info->lock);
return;
}
usb_serial_debug_data(debug, &port->dev, __FUNCTION__, urb->actual_length, data);
spin_lock(&info->lock);
list_add_tail(&wrap->list, &info->rx_urb_q);
if (info->flags & THROTTLED) {
info->flags |= ACTUALLY_THROTTLED;
spin_unlock(&info->lock);
return;
}
spin_unlock(&info->lock);
schedule_work(&info->rx_work);
}
static void whiteheat_write_callback(struct urb *urb)
{
struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
struct whiteheat_private *info = usb_get_serial_port_data(port);
struct whiteheat_urb_wrap *wrap;
dbg("%s - port %d", __FUNCTION__, port->number);
spin_lock(&info->lock);
wrap = urb_to_wrap(urb, &info->tx_urbs_submitted);
if (!wrap) {
spin_unlock(&info->lock);
err("%s - Not my urb!", __FUNCTION__);
return;
}
list_move(&wrap->list, &info->tx_urbs_free);
spin_unlock(&info->lock);
if (urb->status) {
dbg("%s - nonzero write bulk status received: %d", __FUNCTION__, urb->status);
return;
}
usb_serial_port_softint(port);
}
/*****************************************************************************
* Connect Tech's White Heat firmware interface
*****************************************************************************/
static int firm_send_command (struct usb_serial_port *port, __u8 command, __u8 *data, __u8 datasize)
{
struct usb_serial_port *command_port;
struct whiteheat_command_private *command_info;
struct whiteheat_private *info;
__u8 *transfer_buffer;
int retval = 0;
unsigned long flags;
dbg("%s - command %d", __FUNCTION__, command);
command_port = port->serial->port[COMMAND_PORT];
command_info = usb_get_serial_port_data(command_port);
spin_lock_irqsave(&command_info->lock, flags);
command_info->command_finished = FALSE;
transfer_buffer = (__u8 *)command_port->write_urb->transfer_buffer;
transfer_buffer[0] = command;
memcpy (&transfer_buffer[1], data, datasize);
command_port->write_urb->transfer_buffer_length = datasize + 1;
command_port->write_urb->dev = port->serial->dev;
retval = usb_submit_urb (command_port->write_urb, GFP_KERNEL);
if (retval) {
dbg("%s - submit urb failed", __FUNCTION__);
goto exit;
}
spin_unlock_irqrestore(&command_info->lock, flags);
/* wait for the command to complete */
wait_event_interruptible_timeout(command_info->wait_command,
(command_info->command_finished != FALSE), COMMAND_TIMEOUT);
spin_lock_irqsave(&command_info->lock, flags);
if (command_info->command_finished == FALSE) {
dbg("%s - command timed out.", __FUNCTION__);
retval = -ETIMEDOUT;
goto exit;
}
if (command_info->command_finished == WHITEHEAT_CMD_FAILURE) {
dbg("%s - command failed.", __FUNCTION__);
retval = -EIO;
goto exit;
}
if (command_info->command_finished == WHITEHEAT_CMD_COMPLETE) {
dbg("%s - command completed.", __FUNCTION__);
switch (command) {
case WHITEHEAT_GET_DTR_RTS:
info = usb_get_serial_port_data(port);
memcpy(&info->mcr, command_info->result_buffer, sizeof(struct whiteheat_dr_info));
break;
}
}
exit:
spin_unlock_irqrestore(&command_info->lock, flags);
return retval;
}
static int firm_open(struct usb_serial_port *port) {
struct whiteheat_simple open_command;
open_command.port = port->number - port->serial->minor + 1;
return firm_send_command(port, WHITEHEAT_OPEN, (__u8 *)&open_command, sizeof(open_command));
}
static int firm_close(struct usb_serial_port *port) {
struct whiteheat_simple close_command;
close_command.port = port->number - port->serial->minor + 1;
return firm_send_command(port, WHITEHEAT_CLOSE, (__u8 *)&close_command, sizeof(close_command));
}
static int firm_setup_port(struct usb_serial_port *port) {
struct whiteheat_port_settings port_settings;
unsigned int cflag = port->tty->termios->c_cflag;
port_settings.port = port->number + 1;
/* get the byte size */
switch (cflag & CSIZE) {
case CS5: port_settings.bits = 5; break;
case CS6: port_settings.bits = 6; break;
case CS7: port_settings.bits = 7; break;
default:
case CS8: port_settings.bits = 8; break;
}
dbg("%s - data bits = %d", __FUNCTION__, port_settings.bits);
/* determine the parity */
if (cflag & PARENB)
if (cflag & CMSPAR)
if (cflag & PARODD)
port_settings.parity = WHITEHEAT_PAR_MARK;
else
port_settings.parity = WHITEHEAT_PAR_SPACE;
else
if (cflag & PARODD)
port_settings.parity = WHITEHEAT_PAR_ODD;
else
port_settings.parity = WHITEHEAT_PAR_EVEN;
else
port_settings.parity = WHITEHEAT_PAR_NONE;
dbg("%s - parity = %c", __FUNCTION__, port_settings.parity);
/* figure out the stop bits requested */
if (cflag & CSTOPB)
port_settings.stop = 2;
else
port_settings.stop = 1;
dbg("%s - stop bits = %d", __FUNCTION__, port_settings.stop);
/* figure out the flow control settings */
if (cflag & CRTSCTS)
port_settings.hflow = (WHITEHEAT_HFLOW_CTS | WHITEHEAT_HFLOW_RTS);
else
port_settings.hflow = WHITEHEAT_HFLOW_NONE;
dbg("%s - hardware flow control = %s %s %s %s", __FUNCTION__,
(port_settings.hflow & WHITEHEAT_HFLOW_CTS) ? "CTS" : "",
(port_settings.hflow & WHITEHEAT_HFLOW_RTS) ? "RTS" : "",
(port_settings.hflow & WHITEHEAT_HFLOW_DSR) ? "DSR" : "",
(port_settings.hflow & WHITEHEAT_HFLOW_DTR) ? "DTR" : "");
/* determine software flow control */
if (I_IXOFF(port->tty))
port_settings.sflow = WHITEHEAT_SFLOW_RXTX;
else
port_settings.sflow = WHITEHEAT_SFLOW_NONE;
dbg("%s - software flow control = %c", __FUNCTION__, port_settings.sflow);
port_settings.xon = START_CHAR(port->tty);
port_settings.xoff = STOP_CHAR(port->tty);
dbg("%s - XON = %2x, XOFF = %2x", __FUNCTION__, port_settings.xon, port_settings.xoff);
/* get the baud rate wanted */
port_settings.baud = tty_get_baud_rate(port->tty);
dbg("%s - baud rate = %d", __FUNCTION__, port_settings.baud);
/* handle any settings that aren't specified in the tty structure */
port_settings.lloop = 0;
/* now send the message to the device */
return firm_send_command(port, WHITEHEAT_SETUP_PORT, (__u8 *)&port_settings, sizeof(port_settings));
}
static int firm_set_rts(struct usb_serial_port *port, __u8 onoff) {
struct whiteheat_set_rdb rts_command;
rts_command.port = port->number - port->serial->minor + 1;
rts_command.state = onoff;
return firm_send_command(port, WHITEHEAT_SET_RTS, (__u8 *)&rts_command, sizeof(rts_command));
}
static int firm_set_dtr(struct usb_serial_port *port, __u8 onoff) {
struct whiteheat_set_rdb dtr_command;
dtr_command.port = port->number - port->serial->minor + 1;
dtr_command.state = onoff;
return firm_send_command(port, WHITEHEAT_SET_RTS, (__u8 *)&dtr_command, sizeof(dtr_command));
}
static int firm_set_break(struct usb_serial_port *port, __u8 onoff) {
struct whiteheat_set_rdb break_command;
break_command.port = port->number - port->serial->minor + 1;
break_command.state = onoff;
return firm_send_command(port, WHITEHEAT_SET_RTS, (__u8 *)&break_command, sizeof(break_command));
}
static int firm_purge(struct usb_serial_port *port, __u8 rxtx) {
struct whiteheat_purge purge_command;
purge_command.port = port->number - port->serial->minor + 1;
purge_command.what = rxtx;
return firm_send_command(port, WHITEHEAT_PURGE, (__u8 *)&purge_command, sizeof(purge_command));
}
static int firm_get_dtr_rts(struct usb_serial_port *port) {
struct whiteheat_simple get_dr_command;
get_dr_command.port = port->number - port->serial->minor + 1;
return firm_send_command(port, WHITEHEAT_GET_DTR_RTS, (__u8 *)&get_dr_command, sizeof(get_dr_command));
}
static int firm_report_tx_done(struct usb_serial_port *port) {
struct whiteheat_simple close_command;
close_command.port = port->number - port->serial->minor + 1;
return firm_send_command(port, WHITEHEAT_REPORT_TX_DONE, (__u8 *)&close_command, sizeof(close_command));
}
/*****************************************************************************
* Connect Tech's White Heat utility functions
*****************************************************************************/
static int start_command_port(struct usb_serial *serial)
{
struct usb_serial_port *command_port;
struct whiteheat_command_private *command_info;
unsigned long flags;
int retval = 0;
command_port = serial->port[COMMAND_PORT];
command_info = usb_get_serial_port_data(command_port);
spin_lock_irqsave(&command_info->lock, flags);
if (!command_info->port_running) {
/* Work around HCD bugs */
usb_clear_halt(serial->dev, command_port->read_urb->pipe);
command_port->read_urb->dev = serial->dev;
retval = usb_submit_urb(command_port->read_urb, GFP_KERNEL);
if (retval) {
err("%s - failed submitting read urb, error %d", __FUNCTION__, retval);
goto exit;
}
}
command_info->port_running++;
exit:
spin_unlock_irqrestore(&command_info->lock, flags);
return retval;
}
static void stop_command_port(struct usb_serial *serial)
{
struct usb_serial_port *command_port;
struct whiteheat_command_private *command_info;
unsigned long flags;
command_port = serial->port[COMMAND_PORT];
command_info = usb_get_serial_port_data(command_port);
spin_lock_irqsave(&command_info->lock, flags);
command_info->port_running--;
if (!command_info->port_running)
usb_kill_urb(command_port->read_urb);
spin_unlock_irqrestore(&command_info->lock, flags);
}
static int start_port_read(struct usb_serial_port *port)
{
struct whiteheat_private *info = usb_get_serial_port_data(port);
struct whiteheat_urb_wrap *wrap;
struct urb *urb;
int retval = 0;
unsigned long flags;
struct list_head *tmp;
struct list_head *tmp2;
spin_lock_irqsave(&info->lock, flags);
list_for_each_safe(tmp, tmp2, &info->rx_urbs_free) {
list_del(tmp);
wrap = list_entry(tmp, struct whiteheat_urb_wrap, list);
urb = wrap->urb;
urb->dev = port->serial->dev;
retval = usb_submit_urb(urb, GFP_KERNEL);
if (retval) {
list_add(tmp, &info->rx_urbs_free);
list_for_each_safe(tmp, tmp2, &info->rx_urbs_submitted) {
wrap = list_entry(tmp, struct whiteheat_urb_wrap, list);
urb = wrap->urb;
usb_kill_urb(urb);
list_move(tmp, &info->rx_urbs_free);
}
break;
}
list_add(tmp, &info->rx_urbs_submitted);
}
spin_unlock_irqrestore(&info->lock, flags);
return retval;
}
static struct whiteheat_urb_wrap *urb_to_wrap(struct urb* urb, struct list_head *head)
{
struct whiteheat_urb_wrap *wrap;
struct list_head *tmp;
list_for_each(tmp, head) {
wrap = list_entry(tmp, struct whiteheat_urb_wrap, list);
if (wrap->urb == urb)
return wrap;
}
return NULL;
}
static struct list_head *list_first(struct list_head *head)
{
return head->next;
}
static void rx_data_softint(struct work_struct *work)
{
struct whiteheat_private *info =
container_of(work, struct whiteheat_private, rx_work);
struct usb_serial_port *port = info->port;
struct tty_struct *tty = port->tty;
struct whiteheat_urb_wrap *wrap;
struct urb *urb;
unsigned long flags;
struct list_head *tmp;
struct list_head *tmp2;
int result;
int sent = 0;
spin_lock_irqsave(&info->lock, flags);
if (info->flags & THROTTLED) {
spin_unlock_irqrestore(&info->lock, flags);
return;
}
list_for_each_safe(tmp, tmp2, &info->rx_urb_q) {
list_del(tmp);
spin_unlock_irqrestore(&info->lock, flags);
wrap = list_entry(tmp, struct whiteheat_urb_wrap, list);
urb = wrap->urb;
if (tty && urb->actual_length) {
int len = tty_buffer_request_room(tty, urb->actual_length);
/* This stuff can go away now I suspect */
if (unlikely(len < urb->actual_length)) {
spin_lock_irqsave(&info->lock, flags);
list_add(tmp, &info->rx_urb_q);
spin_unlock_irqrestore(&info->lock, flags);
tty_flip_buffer_push(tty);
schedule_work(&info->rx_work);
return;
}
tty_insert_flip_string(tty, urb->transfer_buffer, len);
sent += len;
}
urb->dev = port->serial->dev;
result = usb_submit_urb(urb, GFP_ATOMIC);
if (result) {
err("%s - failed resubmitting read urb, error %d", __FUNCTION__, result);
spin_lock_irqsave(&info->lock, flags);
list_add(tmp, &info->rx_urbs_free);
continue;
}
spin_lock_irqsave(&info->lock, flags);
list_add(tmp, &info->rx_urbs_submitted);
}
spin_unlock_irqrestore(&info->lock, flags);
if (sent)
tty_flip_buffer_push(tty);
}
/*****************************************************************************
* Connect Tech's White Heat module functions
*****************************************************************************/
static int __init whiteheat_init (void)
{
int retval;
retval = usb_serial_register(&whiteheat_fake_device);
if (retval)
goto failed_fake_register;
retval = usb_serial_register(&whiteheat_device);
if (retval)
goto failed_device_register;
retval = usb_register(&whiteheat_driver);
if (retval)
goto failed_usb_register;
info(DRIVER_DESC " " DRIVER_VERSION);
return 0;
failed_usb_register:
usb_serial_deregister(&whiteheat_device);
failed_device_register:
usb_serial_deregister(&whiteheat_fake_device);
failed_fake_register:
return retval;
}
static void __exit whiteheat_exit (void)
{
usb_deregister (&whiteheat_driver);
usb_serial_deregister (&whiteheat_fake_device);
usb_serial_deregister (&whiteheat_device);
}
module_init(whiteheat_init);
module_exit(whiteheat_exit);
MODULE_AUTHOR( DRIVER_AUTHOR );
MODULE_DESCRIPTION( DRIVER_DESC );
MODULE_LICENSE("GPL");
module_param(urb_pool_size, int, 0);
MODULE_PARM_DESC(urb_pool_size, "Number of urbs to use for buffering");
module_param(debug, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(debug, "Debug enabled or not");
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