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linux/drivers/net/hamradio/baycom_ser_fdx.c
Thomas Gleixner 3f5296f0e8 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 69 
Based on 1 normalized pattern(s):

  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 this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details you
  should have received a copy of the gnu general public license along
  with this program if not write to the free software foundation inc
  675 mass ave cambridge ma 02139 usa please note that the gpl allows
  you to use the driver not the radio in order to use the radio you
  need a license from the communications authority of your country

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 7 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190520071859.472520794@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-24 17:36:47 +02:00

678 lines
19 KiB
C
Raw Blame History

// SPDX-License-Identifier: GPL-2.0-or-later
/*****************************************************************************/
/*
* baycom_ser_fdx.c -- baycom ser12 fullduplex radio modem driver.
*
* Copyright (C) 1996-2000 Thomas Sailer (sailer@ife.ee.ethz.ch)
*
* Please note that the GPL allows you to use the driver, NOT the radio.
* In order to use the radio, you need a license from the communications
* authority of your country.
*
* Supported modems
*
* ser12: This is a very simple 1200 baud AFSK modem. The modem consists only
* of a modulator/demodulator chip, usually a TI TCM3105. The computer
* is responsible for regenerating the receiver bit clock, as well as
* for handling the HDLC protocol. The modem connects to a serial port,
* hence the name. Since the serial port is not used as an async serial
* port, the kernel driver for serial ports cannot be used, and this
* driver only supports standard serial hardware (8250, 16450, 16550A)
*
* This modem usually draws its supply current out of the otherwise unused
* TXD pin of the serial port. Thus a contiguous stream of 0x00-bytes
* is transmitted to achieve a positive supply voltage.
*
* hsk: This is a 4800 baud FSK modem, designed for TNC use. It works fine
* in 'baycom-mode' :-) In contrast to the TCM3105 modem, power is
* externally supplied. So there's no need to provide the 0x00-byte-stream
* when receiving or idle, which drastically reduces interrupt load.
*
* Command line options (insmod command line)
*
* mode ser# hardware DCD
* ser#* software DCD
* ser#+ hardware DCD, inverted signal at DCD pin
* '#' denotes the baud rate / 100, eg. ser12* is '1200 baud, soft DCD'
* iobase base address of the port; common values are 0x3f8, 0x2f8, 0x3e8, 0x2e8
* baud baud rate (between 300 and 4800)
* irq interrupt line of the port; common values are 4,3
*
* History:
* 0.1 26.06.1996 Adapted from baycom.c and made network driver interface
* 18.10.1996 Changed to new user space access routines (copy_{to,from}_user)
* 0.3 26.04.1997 init code/data tagged
* 0.4 08.07.1997 alternative ser12 decoding algorithm (uses delta CTS ints)
* 0.5 11.11.1997 ser12/par96 split into separate files
* 0.6 24.01.1998 Thorsten Kranzkowski, dl8bcu and Thomas Sailer:
* reduced interrupt load in transmit case
* reworked receiver
* 0.7 03.08.1999 adapt to Linus' new __setup/__initcall
* 0.8 10.08.1999 use module_init/module_exit
* 0.9 12.02.2000 adapted to softnet driver interface
* 0.10 03.07.2000 fix interface name handling
*/
/*****************************************************************************/
#include <linux/capability.h>
#include <linux/module.h>
#include <linux/ioport.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/hdlcdrv.h>
#include <linux/baycom.h>
#include <linux/jiffies.h>
#include <linux/time64.h>
#include <linux/uaccess.h>
#include <asm/io.h>
#include <asm/irq.h>
/* --------------------------------------------------------------------- */
#define BAYCOM_DEBUG
/* --------------------------------------------------------------------- */
static const char bc_drvname[] = "baycom_ser_fdx";
static const char bc_drvinfo[] = KERN_INFO "baycom_ser_fdx: (C) 1996-2000 Thomas Sailer, HB9JNX/AE4WA\n"
"baycom_ser_fdx: version 0.10\n";
/* --------------------------------------------------------------------- */
#define NR_PORTS 4
static struct net_device *baycom_device[NR_PORTS];
/* --------------------------------------------------------------------- */
#define RBR(iobase) (iobase+0)
#define THR(iobase) (iobase+0)
#define IER(iobase) (iobase+1)
#define IIR(iobase) (iobase+2)
#define FCR(iobase) (iobase+2)
#define LCR(iobase) (iobase+3)
#define MCR(iobase) (iobase+4)
#define LSR(iobase) (iobase+5)
#define MSR(iobase) (iobase+6)
#define SCR(iobase) (iobase+7)
#define DLL(iobase) (iobase+0)
#define DLM(iobase) (iobase+1)
#define SER12_EXTENT 8
/* ---------------------------------------------------------------------- */
/*
* Information that need to be kept for each board.
*/
struct baycom_state {
struct hdlcdrv_state hdrv;
unsigned int baud, baud_us, baud_arbdiv, baud_uartdiv, baud_dcdtimeout;
int opt_dcd;
struct modem_state {
unsigned char flags;
unsigned char ptt;
unsigned int shreg;
struct modem_state_ser12 {
unsigned char tx_bit;
unsigned char last_rxbit;
int dcd_sum0, dcd_sum1, dcd_sum2;
int dcd_time;
unsigned int pll_time;
unsigned int txshreg;
} ser12;
} modem;
#ifdef BAYCOM_DEBUG
struct debug_vals {
unsigned long last_jiffies;
unsigned cur_intcnt;
unsigned last_intcnt;
int cur_pllcorr;
int last_pllcorr;
} debug_vals;
#endif /* BAYCOM_DEBUG */
};
/* --------------------------------------------------------------------- */
static inline void baycom_int_freq(struct baycom_state *bc)
{
#ifdef BAYCOM_DEBUG
unsigned long cur_jiffies = jiffies;
/*
* measure the interrupt frequency
*/
bc->debug_vals.cur_intcnt++;
if (time_after_eq(cur_jiffies, bc->debug_vals.last_jiffies + HZ)) {
bc->debug_vals.last_jiffies = cur_jiffies;
bc->debug_vals.last_intcnt = bc->debug_vals.cur_intcnt;
bc->debug_vals.cur_intcnt = 0;
bc->debug_vals.last_pllcorr = bc->debug_vals.cur_pllcorr;
bc->debug_vals.cur_pllcorr = 0;
}
#endif /* BAYCOM_DEBUG */
}
/* --------------------------------------------------------------------- */
/*
* ===================== SER12 specific routines =========================
*/
/* --------------------------------------------------------------------- */
static inline void ser12_set_divisor(struct net_device *dev,
unsigned int divisor)
{
outb(0x81, LCR(dev->base_addr)); /* DLAB = 1 */
outb(divisor, DLL(dev->base_addr));
outb(divisor >> 8, DLM(dev->base_addr));
outb(0x01, LCR(dev->base_addr)); /* word length = 6 */
/*
* make sure the next interrupt is generated;
* 0 must be used to power the modem; the modem draws its
* power from the TxD line
*/
outb(0x00, THR(dev->base_addr));
/*
* it is important not to set the divider while transmitting;
* this reportedly makes some UARTs generating interrupts
* in the hundredthousands per second region
* Reported by: Ignacio.Arenaza@studi.epfl.ch (Ignacio Arenaza Nuno)
*/
}
static __inline__ void ser12_rx(struct net_device *dev, struct baycom_state *bc, struct timespec64 *ts, unsigned char curs)
{
int timediff;
int bdus8 = bc->baud_us >> 3;
int bdus4 = bc->baud_us >> 2;
int bdus2 = bc->baud_us >> 1;
timediff = 1000000 + ts->tv_nsec / NSEC_PER_USEC -
bc->modem.ser12.pll_time;
while (timediff >= 500000)
timediff -= 1000000;
while (timediff >= bdus2) {
timediff -= bc->baud_us;
bc->modem.ser12.pll_time += bc->baud_us;
bc->modem.ser12.dcd_time--;
/* first check if there is room to add a bit */
if (bc->modem.shreg & 1) {
hdlcdrv_putbits(&bc->hdrv, (bc->modem.shreg >> 1) ^ 0xffff);
bc->modem.shreg = 0x10000;
}
/* add a one bit */
bc->modem.shreg >>= 1;
}
if (bc->modem.ser12.dcd_time <= 0) {
if (!bc->opt_dcd)
hdlcdrv_setdcd(&bc->hdrv, (bc->modem.ser12.dcd_sum0 +
bc->modem.ser12.dcd_sum1 +
bc->modem.ser12.dcd_sum2) < 0);
bc->modem.ser12.dcd_sum2 = bc->modem.ser12.dcd_sum1;
bc->modem.ser12.dcd_sum1 = bc->modem.ser12.dcd_sum0;
bc->modem.ser12.dcd_sum0 = 2; /* slight bias */
bc->modem.ser12.dcd_time += 120;
}
if (bc->modem.ser12.last_rxbit != curs) {
bc->modem.ser12.last_rxbit = curs;
bc->modem.shreg |= 0x10000;
/* adjust the PLL */
if (timediff > 0)
bc->modem.ser12.pll_time += bdus8;
else
bc->modem.ser12.pll_time += 1000000 - bdus8;
/* update DCD */
if (abs(timediff) > bdus4)
bc->modem.ser12.dcd_sum0 += 4;
else
bc->modem.ser12.dcd_sum0--;
#ifdef BAYCOM_DEBUG
bc->debug_vals.cur_pllcorr = timediff;
#endif /* BAYCOM_DEBUG */
}
while (bc->modem.ser12.pll_time >= 1000000)
bc->modem.ser12.pll_time -= 1000000;
}
/* --------------------------------------------------------------------- */
static irqreturn_t ser12_interrupt(int irq, void *dev_id)
{
struct net_device *dev = (struct net_device *)dev_id;
struct baycom_state *bc = netdev_priv(dev);
struct timespec64 ts;
unsigned char iir, msr;
unsigned int txcount = 0;
if (!bc || bc->hdrv.magic != HDLCDRV_MAGIC)
return IRQ_NONE;
/* fast way out for shared irq */
if ((iir = inb(IIR(dev->base_addr))) & 1)
return IRQ_NONE;
/* get current time */
ktime_get_ts64(&ts);
msr = inb(MSR(dev->base_addr));
/* delta DCD */
if ((msr & 8) && bc->opt_dcd)
hdlcdrv_setdcd(&bc->hdrv, !((msr ^ bc->opt_dcd) & 0x80));
do {
switch (iir & 6) {
case 6:
inb(LSR(dev->base_addr));
break;
case 4:
inb(RBR(dev->base_addr));
break;
case 2:
/*
* make sure the next interrupt is generated;
* 0 must be used to power the modem; the modem draws its
* power from the TxD line
*/
outb(0x00, THR(dev->base_addr));
baycom_int_freq(bc);
txcount++;
/*
* first output the last bit (!) then call HDLC transmitter,
* since this may take quite long
*/
if (bc->modem.ptt)
outb(0x0e | (!!bc->modem.ser12.tx_bit), MCR(dev->base_addr));
else
outb(0x0d, MCR(dev->base_addr)); /* transmitter off */
break;
default:
msr = inb(MSR(dev->base_addr));
/* delta DCD */
if ((msr & 8) && bc->opt_dcd)
hdlcdrv_setdcd(&bc->hdrv, !((msr ^ bc->opt_dcd) & 0x80));
break;
}
iir = inb(IIR(dev->base_addr));
} while (!(iir & 1));
ser12_rx(dev, bc, &ts, msr & 0x10); /* CTS */
if (bc->modem.ptt && txcount) {
if (bc->modem.ser12.txshreg <= 1) {
bc->modem.ser12.txshreg = 0x10000 | hdlcdrv_getbits(&bc->hdrv);
if (!hdlcdrv_ptt(&bc->hdrv)) {
ser12_set_divisor(dev, 115200/100/8);
bc->modem.ptt = 0;
goto end_transmit;
}
}
bc->modem.ser12.tx_bit = !(bc->modem.ser12.tx_bit ^ (bc->modem.ser12.txshreg & 1));
bc->modem.ser12.txshreg >>= 1;
}
end_transmit:
local_irq_enable();
if (!bc->modem.ptt && txcount) {
hdlcdrv_arbitrate(dev, &bc->hdrv);
if (hdlcdrv_ptt(&bc->hdrv)) {
ser12_set_divisor(dev, bc->baud_uartdiv);
bc->modem.ser12.txshreg = 1;
bc->modem.ptt = 1;
}
}
hdlcdrv_transmitter(dev, &bc->hdrv);
hdlcdrv_receiver(dev, &bc->hdrv);
local_irq_disable();
return IRQ_HANDLED;
}
/* --------------------------------------------------------------------- */
enum uart { c_uart_unknown, c_uart_8250,
c_uart_16450, c_uart_16550, c_uart_16550A};
static const char *uart_str[] = {
"unknown", "8250", "16450", "16550", "16550A"
};
static enum uart ser12_check_uart(unsigned int iobase)
{
unsigned char b1,b2,b3;
enum uart u;
enum uart uart_tab[] =
{ c_uart_16450, c_uart_unknown, c_uart_16550, c_uart_16550A };
b1 = inb(MCR(iobase));
outb(b1 | 0x10, MCR(iobase)); /* loopback mode */
b2 = inb(MSR(iobase));
outb(0x1a, MCR(iobase));
b3 = inb(MSR(iobase)) & 0xf0;
outb(b1, MCR(iobase)); /* restore old values */
outb(b2, MSR(iobase));
if (b3 != 0x90)
return c_uart_unknown;
inb(RBR(iobase));
inb(RBR(iobase));
outb(0x01, FCR(iobase)); /* enable FIFOs */
u = uart_tab[(inb(IIR(iobase)) >> 6) & 3];
if (u == c_uart_16450) {
outb(0x5a, SCR(iobase));
b1 = inb(SCR(iobase));
outb(0xa5, SCR(iobase));
b2 = inb(SCR(iobase));
if ((b1 != 0x5a) || (b2 != 0xa5))
u = c_uart_8250;
}
return u;
}
/* --------------------------------------------------------------------- */
static int ser12_open(struct net_device *dev)
{
struct baycom_state *bc = netdev_priv(dev);
enum uart u;
if (!dev || !bc)
return -ENXIO;
if (!dev->base_addr || dev->base_addr > 0xffff-SER12_EXTENT ||
dev->irq < 2 || dev->irq > nr_irqs) {
printk(KERN_INFO "baycom_ser_fdx: invalid portnumber (max %u) "
"or irq (2 <= irq <= %d)\n",
0xffff-SER12_EXTENT, nr_irqs);
return -ENXIO;
}
if (bc->baud < 300 || bc->baud > 4800) {
printk(KERN_INFO "baycom_ser_fdx: invalid baudrate "
"(300...4800)\n");
return -EINVAL;
}
if (!request_region(dev->base_addr, SER12_EXTENT, "baycom_ser_fdx")) {
printk(KERN_WARNING "BAYCOM_SER_FSX: I/O port 0x%04lx busy\n",
dev->base_addr);
return -EACCES;
}
memset(&bc->modem, 0, sizeof(bc->modem));
bc->hdrv.par.bitrate = bc->baud;
bc->baud_us = 1000000/bc->baud;
bc->baud_uartdiv = (115200/8)/bc->baud;
if ((u = ser12_check_uart(dev->base_addr)) == c_uart_unknown){
release_region(dev->base_addr, SER12_EXTENT);
return -EIO;
}
outb(0, FCR(dev->base_addr)); /* disable FIFOs */
outb(0x0d, MCR(dev->base_addr));
outb(0, IER(dev->base_addr));
if (request_irq(dev->irq, ser12_interrupt, IRQF_SHARED,
"baycom_ser_fdx", dev)) {
release_region(dev->base_addr, SER12_EXTENT);
return -EBUSY;
}
/*
* set the SIO to 6 Bits/character; during receive,
* the baud rate is set to produce 100 ints/sec
* to feed the channel arbitration process,
* during transmit to baud ints/sec to run
* the transmitter
*/
ser12_set_divisor(dev, 115200/100/8);
/*
* enable transmitter empty interrupt and modem status interrupt
*/
outb(0x0a, IER(dev->base_addr));
/*
* make sure the next interrupt is generated;
* 0 must be used to power the modem; the modem draws its
* power from the TxD line
*/
outb(0x00, THR(dev->base_addr));
hdlcdrv_setdcd(&bc->hdrv, 0);
printk(KERN_INFO "%s: ser_fdx at iobase 0x%lx irq %u baud %u uart %s\n",
bc_drvname, dev->base_addr, dev->irq, bc->baud, uart_str[u]);
return 0;
}
/* --------------------------------------------------------------------- */
static int ser12_close(struct net_device *dev)
{
struct baycom_state *bc = netdev_priv(dev);
if (!dev || !bc)
return -EINVAL;
/*
* disable interrupts
*/
outb(0, IER(dev->base_addr));
outb(1, MCR(dev->base_addr));
free_irq(dev->irq, dev);
release_region(dev->base_addr, SER12_EXTENT);
printk(KERN_INFO "%s: close ser_fdx at iobase 0x%lx irq %u\n",
bc_drvname, dev->base_addr, dev->irq);
return 0;
}
/* --------------------------------------------------------------------- */
/*
* ===================== hdlcdrv driver interface =========================
*/
/* --------------------------------------------------------------------- */
static int baycom_ioctl(struct net_device *dev, struct ifreq *ifr,
struct hdlcdrv_ioctl *hi, int cmd);
/* --------------------------------------------------------------------- */
static const struct hdlcdrv_ops ser12_ops = {
.drvname = bc_drvname,
.drvinfo = bc_drvinfo,
.open = ser12_open,
.close = ser12_close,
.ioctl = baycom_ioctl,
};
/* --------------------------------------------------------------------- */
static int baycom_setmode(struct baycom_state *bc, const char *modestr)
{
unsigned int baud;
if (!strncmp(modestr, "ser", 3)) {
baud = simple_strtoul(modestr+3, NULL, 10);
if (baud >= 3 && baud <= 48)
bc->baud = baud*100;
}
if (strchr(modestr, '*'))
bc->opt_dcd = 0;
else if (strchr(modestr, '+'))
bc->opt_dcd = -1;
else
bc->opt_dcd = 1;
return 0;
}
/* --------------------------------------------------------------------- */
static int baycom_ioctl(struct net_device *dev, struct ifreq *ifr,
struct hdlcdrv_ioctl *hi, int cmd)
{
struct baycom_state *bc;
struct baycom_ioctl bi;
if (!dev)
return -EINVAL;
bc = netdev_priv(dev);
BUG_ON(bc->hdrv.magic != HDLCDRV_MAGIC);
if (cmd != SIOCDEVPRIVATE)
return -ENOIOCTLCMD;
switch (hi->cmd) {
default:
break;
case HDLCDRVCTL_GETMODE:
sprintf(hi->data.modename, "ser%u", bc->baud / 100);
if (bc->opt_dcd <= 0)
strcat(hi->data.modename, (!bc->opt_dcd) ? "*" : "+");
if (copy_to_user(ifr->ifr_data, hi, sizeof(struct hdlcdrv_ioctl)))
return -EFAULT;
return 0;
case HDLCDRVCTL_SETMODE:
if (netif_running(dev) || !capable(CAP_NET_ADMIN))
return -EACCES;
hi->data.modename[sizeof(hi->data.modename)-1] = '\0';
return baycom_setmode(bc, hi->data.modename);
case HDLCDRVCTL_MODELIST:
strcpy(hi->data.modename, "ser12,ser3,ser24");
if (copy_to_user(ifr->ifr_data, hi, sizeof(struct hdlcdrv_ioctl)))
return -EFAULT;
return 0;
case HDLCDRVCTL_MODEMPARMASK:
return HDLCDRV_PARMASK_IOBASE | HDLCDRV_PARMASK_IRQ;
}
if (copy_from_user(&bi, ifr->ifr_data, sizeof(bi)))
return -EFAULT;
switch (bi.cmd) {
default:
return -ENOIOCTLCMD;
#ifdef BAYCOM_DEBUG
case BAYCOMCTL_GETDEBUG:
bi.data.dbg.debug1 = bc->hdrv.ptt_keyed;
bi.data.dbg.debug2 = bc->debug_vals.last_intcnt;
bi.data.dbg.debug3 = bc->debug_vals.last_pllcorr;
break;
#endif /* BAYCOM_DEBUG */
}
if (copy_to_user(ifr->ifr_data, &bi, sizeof(bi)))
return -EFAULT;
return 0;
}
/* --------------------------------------------------------------------- */
/*
* command line settable parameters
*/
static char *mode[NR_PORTS] = { "ser12*", };
static int iobase[NR_PORTS] = { 0x3f8, };
static int irq[NR_PORTS] = { 4, };
static int baud[NR_PORTS] = { [0 ... NR_PORTS-1] = 1200 };
module_param_array(mode, charp, NULL, 0);
MODULE_PARM_DESC(mode, "baycom operating mode; * for software DCD");
module_param_hw_array(iobase, int, ioport, NULL, 0);
MODULE_PARM_DESC(iobase, "baycom io base address");
module_param_hw_array(irq, int, irq, NULL, 0);
MODULE_PARM_DESC(irq, "baycom irq number");
module_param_array(baud, int, NULL, 0);
MODULE_PARM_DESC(baud, "baycom baud rate (300 to 4800)");
MODULE_AUTHOR("Thomas M. Sailer, sailer@ife.ee.ethz.ch, hb9jnx@hb9w.che.eu");
MODULE_DESCRIPTION("Baycom ser12 full duplex amateur radio modem driver");
MODULE_LICENSE("GPL");
/* --------------------------------------------------------------------- */
static int __init init_baycomserfdx(void)
{
int i, found = 0;
char set_hw = 1;
printk(bc_drvinfo);
/*
* register net devices
*/
for (i = 0; i < NR_PORTS; i++) {
struct net_device *dev;
struct baycom_state *bc;
char ifname[IFNAMSIZ];
sprintf(ifname, "bcsf%d", i);
if (!mode[i])
set_hw = 0;
if (!set_hw)
iobase[i] = irq[i] = 0;
dev = hdlcdrv_register(&ser12_ops,
sizeof(struct baycom_state),
ifname, iobase[i], irq[i], 0);
if (IS_ERR(dev))
break;
bc = netdev_priv(dev);
if (set_hw && baycom_setmode(bc, mode[i]))
set_hw = 0;
bc->baud = baud[i];
found++;
baycom_device[i] = dev;
}
if (!found)
return -ENXIO;
return 0;
}
static void __exit cleanup_baycomserfdx(void)
{
int i;
for(i = 0; i < NR_PORTS; i++) {
struct net_device *dev = baycom_device[i];
if (dev)
hdlcdrv_unregister(dev);
}
}
module_init(init_baycomserfdx);
module_exit(cleanup_baycomserfdx);
/* --------------------------------------------------------------------- */
#ifndef MODULE
/*
* format: baycom_ser_fdx=io,irq,mode
* mode: ser# hardware DCD
* ser#* software DCD
* ser#+ hardware DCD, inverted signal at DCD pin
* '#' denotes the baud rate / 100, eg. ser12* is '1200 baud, soft DCD'
*/
static int __init baycom_ser_fdx_setup(char *str)
{
static unsigned nr_dev;
int ints[4];
if (nr_dev >= NR_PORTS)
return 0;
str = get_options(str, 4, ints);
if (ints[0] < 2)
return 0;
mode[nr_dev] = str;
iobase[nr_dev] = ints[1];
irq[nr_dev] = ints[2];
if (ints[0] >= 3)
baud[nr_dev] = ints[3];
nr_dev++;
return 1;
}
__setup("baycom_ser_fdx=", baycom_ser_fdx_setup);
#endif /* MODULE */
/* --------------------------------------------------------------------- */
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