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|
/*****************************************************************************
*
* Filename: stir4200.c
* Version: 0.4
* Description: Irda SigmaTel USB Dongle
* Status: Experimental
* Author: Stephen Hemminger <shemminger@osdl.org>
*
* Based on earlier driver by Paul Stewart <stewart@parc.com>
*
* Copyright (C) 2000, Roman Weissgaerber <weissg@vienna.at>
* Copyright (C) 2001, Dag Brattli <dag@brattli.net>
* Copyright (C) 2001, Jean Tourrilhes <jt@hpl.hp.com>
* Copyright (C) 2004, Stephen Hemminger <shemminger@osdl.org>
*
* 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.
*
* 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.
*
*****************************************************************************/
/*
* This dongle does no framing, and requires polling to receive the
* data. The STIr4200 has bulk in and out endpoints just like
* usr-irda devices, but the data it sends and receives is raw; like
* irtty, it needs to call the wrap and unwrap functions to add and
* remove SOF/BOF and escape characters to/from the frame.
*/
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/kernel.h>
#include <linux/sched/signal.h>
#include <linux/ktime.h>
#include <linux/types.h>
#include <linux/time.h>
#include <linux/skbuff.h>
#include <linux/netdevice.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/usb.h>
#include <linux/crc32.h>
#include <linux/kthread.h>
#include <linux/freezer.h>
#include <net/irda/irda.h>
#include <net/irda/irda_device.h>
#include <net/irda/wrapper.h>
#include <net/irda/crc.h>
#include <asm/byteorder.h>
#include <asm/unaligned.h>
MODULE_AUTHOR("Stephen Hemminger <shemminger@linux-foundation.org>");
MODULE_DESCRIPTION("IrDA-USB Dongle Driver for SigmaTel STIr4200");
MODULE_LICENSE("GPL");
static int qos_mtt_bits = 0x07; /* 1 ms or more */
module_param(qos_mtt_bits, int, 0);
MODULE_PARM_DESC(qos_mtt_bits, "Minimum Turn Time");
static int rx_sensitivity = 1; /* FIR 0..4, SIR 0..6 */
module_param(rx_sensitivity, int, 0);
MODULE_PARM_DESC(rx_sensitivity, "Set Receiver sensitivity (0-6, 0 is most sensitive)");
static int tx_power = 0; /* 0 = highest ... 3 = lowest */
module_param(tx_power, int, 0);
MODULE_PARM_DESC(tx_power, "Set Transmitter power (0-3, 0 is highest power)");
#define STIR_IRDA_HEADER 4
#define CTRL_TIMEOUT 100 /* milliseconds */
#define TRANSMIT_TIMEOUT 200 /* milliseconds */
#define STIR_FIFO_SIZE 4096
#define FIFO_REGS_SIZE 3
enum FirChars {
FIR_CE = 0x7d,
FIR_XBOF = 0x7f,
FIR_EOF = 0x7e,
};
enum StirRequests {
REQ_WRITE_REG = 0x00,
REQ_READ_REG = 0x01,
REQ_READ_ROM = 0x02,
REQ_WRITE_SINGLE = 0x03,
};
/* Register offsets */
enum StirRegs {
REG_RSVD=0,
REG_MODE,
REG_PDCLK,
REG_CTRL1,
REG_CTRL2,
REG_FIFOCTL,
REG_FIFOLSB,
REG_FIFOMSB,
REG_DPLL,
REG_IRDIG,
REG_TEST=15,
};
enum StirModeMask {
MODE_FIR = 0x80,
MODE_SIR = 0x20,
MODE_ASK = 0x10,
MODE_FASTRX = 0x08,
MODE_FFRSTEN = 0x04,
MODE_NRESET = 0x02,
MODE_2400 = 0x01,
};
enum StirPdclkMask {
PDCLK_4000000 = 0x02,
PDCLK_115200 = 0x09,
PDCLK_57600 = 0x13,
PDCLK_38400 = 0x1D,
PDCLK_19200 = 0x3B,
PDCLK_9600 = 0x77,
PDCLK_2400 = 0xDF,
};
enum StirCtrl1Mask {
CTRL1_SDMODE = 0x80,
CTRL1_RXSLOW = 0x40,
CTRL1_TXPWD = 0x10,
CTRL1_RXPWD = 0x08,
CTRL1_SRESET = 0x01,
};
enum StirCtrl2Mask {
CTRL2_SPWIDTH = 0x08,
CTRL2_REVID = 0x03,
};
enum StirFifoCtlMask {
FIFOCTL_DIR = 0x10,
FIFOCTL_CLR = 0x08,
FIFOCTL_EMPTY = 0x04,
};
enum StirDiagMask {
IRDIG_RXHIGH = 0x80,
IRDIG_RXLOW = 0x40,
};
enum StirTestMask {
TEST_PLLDOWN = 0x80,
TEST_LOOPIR = 0x40,
TEST_LOOPUSB = 0x20,
TEST_TSTENA = 0x10,
TEST_TSTOSC = 0x0F,
};
struct stir_cb {
struct usb_device *usbdev; /* init: probe_irda */
struct net_device *netdev; /* network layer */
struct irlap_cb *irlap; /* The link layer we are binded to */
struct qos_info qos;
unsigned speed; /* Current speed */
struct task_struct *thread; /* transmit thread */
struct sk_buff *tx_pending;
void *io_buf; /* transmit/receive buffer */
__u8 *fifo_status;
iobuff_t rx_buff; /* receive unwrap state machine */
ktime_t rx_time;
int receiving;
struct urb *rx_urb;
};
/* These are the currently known USB ids */
static const struct usb_device_id dongles[] = {
/* SigmaTel, Inc, STIr4200 IrDA/USB Bridge */
{ USB_DEVICE(0x066f, 0x4200) },
{ }
};
MODULE_DEVICE_TABLE(usb, dongles);
/* Send control message to set dongle register */
static int write_reg(struct stir_cb *stir, __u16 reg, __u8 value)
{
struct usb_device *dev = stir->usbdev;
pr_debug("%s: write reg %d = 0x%x\n",
stir->netdev->name, reg, value);
return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
REQ_WRITE_SINGLE,
USB_DIR_OUT|USB_TYPE_VENDOR|USB_RECIP_DEVICE,
value, reg, NULL, 0,
CTRL_TIMEOUT);
}
/* Send control message to read multiple registers */
static inline int read_reg(struct stir_cb *stir, __u16 reg,
__u8 *data, __u16 count)
{
struct usb_device *dev = stir->usbdev;
return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
REQ_READ_REG,
USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
0, reg, data, count,
CTRL_TIMEOUT);
}
static inline int isfir(u32 speed)
{
return speed == 4000000;
}
/*
* Prepare a FIR IrDA frame for transmission to the USB dongle. The
* FIR transmit frame is documented in the datasheet. It consists of
* a two byte 0x55 0xAA sequence, two little-endian length bytes, a
* sequence of exactly 16 XBOF bytes of 0x7E, two BOF bytes of 0x7E,
* then the data escaped as follows:
*
* 0x7D -> 0x7D 0x5D
* 0x7E -> 0x7D 0x5E
* 0x7F -> 0x7D 0x5F
*
* Then, 4 bytes of little endian (stuffed) FCS follow, then two
* trailing EOF bytes of 0x7E.
*/
static inline __u8 *stuff_fir(__u8 *p, __u8 c)
{
switch(c) {
case 0x7d:
case 0x7e:
case 0x7f:
*p++ = 0x7d;
c ^= IRDA_TRANS;
/* fall through */
default:
*p++ = c;
}
return p;
}
/* Take raw data in skb and put it wrapped into buf */
static unsigned wrap_fir_skb(const struct sk_buff *skb, __u8 *buf)
{
__u8 *ptr = buf;
__u32 fcs = ~(crc32_le(~0, skb->data, skb->len));
__u16 wraplen;
int i;
/* Header */
buf[0] = 0x55;
buf[1] = 0xAA;
ptr = buf + STIR_IRDA_HEADER;
memset(ptr, 0x7f, 16);
ptr += 16;
/* BOF */
*ptr++ = 0x7e;
*ptr++ = 0x7e;
/* Address / Control / Information */
for (i = 0; i < skb->len; i++)
ptr = stuff_fir(ptr, skb->data[i]);
/* FCS */
ptr = stuff_fir(ptr, fcs & 0xff);
ptr = stuff_fir(ptr, (fcs >> 8) & 0xff);
ptr = stuff_fir(ptr, (fcs >> 16) & 0xff);
ptr = stuff_fir(ptr, (fcs >> 24) & 0xff);
/* EOFs */
*ptr++ = 0x7e;
*ptr++ = 0x7e;
/* Total length, minus the header */
wraplen = (ptr - buf) - STIR_IRDA_HEADER;
buf[2] = wraplen & 0xff;
buf[3] = (wraplen >> 8) & 0xff;
return wraplen + STIR_IRDA_HEADER;
}
static unsigned wrap_sir_skb(struct sk_buff *skb, __u8 *buf)
{
__u16 wraplen;
wraplen = async_wrap_skb(skb, buf + STIR_IRDA_HEADER,
STIR_FIFO_SIZE - STIR_IRDA_HEADER);
buf[0] = 0x55;
buf[1] = 0xAA;
buf[2] = wraplen & 0xff;
buf[3] = (wraplen >> 8) & 0xff;
return wraplen + STIR_IRDA_HEADER;
}
/*
* Frame is fully formed in the rx_buff so check crc
* and pass up to irlap
* setup for next receive
*/
static void fir_eof(struct stir_cb *stir)
{
iobuff_t *rx_buff = &stir->rx_buff;
int len = rx_buff->len - 4;
struct sk_buff *skb, *nskb;
__u32 fcs;
if (unlikely(len <= 0)) {
pr_debug("%s: short frame len %d\n",
stir->netdev->name, len);
++stir->netdev->stats.rx_errors;
++stir->netdev->stats.rx_length_errors;
return;
}
fcs = ~(crc32_le(~0, rx_buff->data, len));
if (fcs != get_unaligned_le32(rx_buff->data + len)) {
pr_debug("crc error calc 0x%x len %d\n", fcs, len);
stir->netdev->stats.rx_errors++;
stir->netdev->stats.rx_crc_errors++;
return;
}
/* if frame is short then just copy it */
if (len < IRDA_RX_COPY_THRESHOLD) {
nskb = dev_alloc_skb(len + 1);
if (unlikely(!nskb)) {
++stir->netdev->stats.rx_dropped;
return;
}
skb_reserve(nskb, 1);
skb = nskb;
skb_copy_to_linear_data(nskb, rx_buff->data, len);
} else {
nskb = dev_alloc_skb(rx_buff->truesize);
if (unlikely(!nskb)) {
++stir->netdev->stats.rx_dropped;
return;
}
skb_reserve(nskb, 1);
skb = rx_buff->skb;
rx_buff->skb = nskb;
rx_buff->head = nskb->data;
}
skb_put(skb, len);
skb_reset_mac_header(skb);
skb->protocol = htons(ETH_P_IRDA);
skb->dev = stir->netdev;
netif_rx(skb);
stir->netdev->stats.rx_packets++;
stir->netdev->stats.rx_bytes += len;
rx_buff->data = rx_buff->head;
rx_buff->len = 0;
}
/* Unwrap FIR stuffed data and bump it to IrLAP */
static void stir_fir_chars(struct stir_cb *stir,
const __u8 *bytes, int len)
{
iobuff_t *rx_buff = &stir->rx_buff;
int i;
for (i = 0; i < len; i++) {
__u8 byte = bytes[i];
switch(rx_buff->state) {
case OUTSIDE_FRAME:
/* ignore garbage till start of frame */
if (unlikely(byte != FIR_EOF))
continue;
/* Now receiving frame */
rx_buff->state = BEGIN_FRAME;
/* Time to initialize receive buffer */
rx_buff->data = rx_buff->head;
rx_buff->len = 0;
continue;
case LINK_ESCAPE:
if (byte == FIR_EOF) {
pr_debug("%s: got EOF after escape\n",
stir->netdev->name);
goto frame_error;
}
rx_buff->state = INSIDE_FRAME;
byte ^= IRDA_TRANS;
break;
case BEGIN_FRAME:
/* ignore multiple BOF/EOF */
if (byte == FIR_EOF)
continue;
rx_buff->state = INSIDE_FRAME;
rx_buff->in_frame = TRUE;
/* fall through */
case INSIDE_FRAME:
switch(byte) {
case FIR_CE:
rx_buff->state = LINK_ESCAPE;
continue;
case FIR_XBOF:
/* 0x7f is not used in this framing */
pr_debug("%s: got XBOF without escape\n",
stir->netdev->name);
goto frame_error;
case FIR_EOF:
rx_buff->state = OUTSIDE_FRAME;
rx_buff->in_frame = FALSE;
fir_eof(stir);
continue;
}
break;
}
/* add byte to rx buffer */
if (unlikely(rx_buff->len >= rx_buff->truesize)) {
pr_debug("%s: fir frame exceeds %d\n",
stir->netdev->name, rx_buff->truesize);
++stir->netdev->stats.rx_over_errors;
goto error_recovery;
}
rx_buff->data[rx_buff->len++] = byte;
continue;
frame_error:
++stir->netdev->stats.rx_frame_errors;
error_recovery:
++stir->netdev->stats.rx_errors;
rx_buff->state = OUTSIDE_FRAME;
rx_buff->in_frame = FALSE;
}
}
/* Unwrap SIR stuffed data and bump it up to IrLAP */
static void stir_sir_chars(struct stir_cb *stir,
const __u8 *bytes, int len)
{
int i;
for (i = 0; i < len; i++)
async_unwrap_char(stir->netdev, &stir->netdev->stats,
&stir->rx_buff, bytes[i]);
}
static inline void unwrap_chars(struct stir_cb *stir,
const __u8 *bytes, int length)
{
if (isfir(stir->speed))
stir_fir_chars(stir, bytes, length);
else
stir_sir_chars(stir, bytes, length);
}
/* Mode parameters for each speed */
static const struct {
unsigned speed;
__u8 pdclk;
} stir_modes[] = {
{ 2400, PDCLK_2400 },
{ 9600, PDCLK_9600 },
{ 19200, PDCLK_19200 },
{ 38400, PDCLK_38400 },
{ 57600, PDCLK_57600 },
{ 115200, PDCLK_115200 },
{ 4000000, PDCLK_4000000 },
};
/*
* Setup chip for speed.
* Called at startup to initialize the chip
* and on speed changes.
*
* Note: Write multiple registers doesn't appear to work
*/
static int change_speed(struct stir_cb *stir, unsigned speed)
{
int i, err;
__u8 mode;
for (i = 0; i < ARRAY_SIZE(stir_modes); ++i) {
if (speed == stir_modes[i].speed)
goto found;
}
dev_warn(&stir->netdev->dev, "invalid speed %d\n", speed);
return -EINVAL;
found:
pr_debug("speed change from %d to %d\n", stir->speed, speed);
/* Reset modulator */
err = write_reg(stir, REG_CTRL1, CTRL1_SRESET);
if (err)
goto out;
/* Undocumented magic to tweak the DPLL */
err = write_reg(stir, REG_DPLL, 0x15);
if (err)
goto out;
/* Set clock */
err = write_reg(stir, REG_PDCLK, stir_modes[i].pdclk);
if (err)
goto out;
mode = MODE_NRESET | MODE_FASTRX;
if (isfir(speed))
mode |= MODE_FIR | MODE_FFRSTEN;
else
mode |= MODE_SIR;
if (speed == 2400)
mode |= MODE_2400;
err = write_reg(stir, REG_MODE, mode);
if (err)
goto out;
/* This resets TEMIC style transceiver if any. */
err = write_reg(stir, REG_CTRL1,
CTRL1_SDMODE | (tx_power & 3) << 1);
if (err)
goto out;
err = write_reg(stir, REG_CTRL1, (tx_power & 3) << 1);
if (err)
goto out;
/* Reset sensitivity */
err = write_reg(stir, REG_CTRL2, (rx_sensitivity & 7) << 5);
out:
stir->speed = speed;
return err;
}
/*
* Called from net/core when new frame is available.
*/
static netdev_tx_t stir_hard_xmit(struct sk_buff *skb,
struct net_device *netdev)
{
struct stir_cb *stir = netdev_priv(netdev);
netif_stop_queue(netdev);
/* the IRDA wrapping routines don't deal with non linear skb */
SKB_LINEAR_ASSERT(skb);
skb = xchg(&stir->tx_pending, skb);
wake_up_process(stir->thread);
/* this should never happen unless stop/wakeup problem */
if (unlikely(skb)) {
WARN_ON(1);
dev_kfree_skb(skb);
}
return NETDEV_TX_OK;
}
/*
* Wait for the transmit FIFO to have space for next data
*
* If space < 0 then wait till FIFO completely drains.
* FYI: can take up to 13 seconds at 2400baud.
*/
static int fifo_txwait(struct stir_cb *stir, int space)
{
int err;
unsigned long count, status;
unsigned long prev_count = 0x1fff;
/* Read FIFO status and count */
for (;; prev_count = count) {
err = read_reg(stir, REG_FIFOCTL, stir->fifo_status,
FIFO_REGS_SIZE);
if (unlikely(err != FIFO_REGS_SIZE)) {
dev_warn(&stir->netdev->dev,
"FIFO register read error: %d\n", err);
return err;
}
status = stir->fifo_status[0];
count = (unsigned)(stir->fifo_status[2] & 0x1f) << 8
| stir->fifo_status[1];
pr_debug("fifo status 0x%lx count %lu\n", status, count);
/* is fifo receiving already, or empty */
if (!(status & FIFOCTL_DIR) ||
(status & FIFOCTL_EMPTY))
return 0;
if (signal_pending(current))
return -EINTR;
/* shutting down? */
if (!netif_running(stir->netdev) ||
!netif_device_present(stir->netdev))
return -ESHUTDOWN;
/* only waiting for some space */
if (space >= 0 && STIR_FIFO_SIZE - 4 > space + count)
return 0;
/* queue confused */
if (prev_count < count)
break;
/* estimate transfer time for remaining chars */
msleep((count * 8000) / stir->speed);
}
err = write_reg(stir, REG_FIFOCTL, FIFOCTL_CLR);
if (err)
return err;
err = write_reg(stir, REG_FIFOCTL, 0);
if (err)
return err;
return 0;
}
/* Wait for turnaround delay before starting transmit. */
static void turnaround_delay(const struct stir_cb *stir, long us)
{
long ticks;
if (us <= 0)
return;
us -= ktime_us_delta(ktime_get(), stir->rx_time);
if (us < 10)
return;
ticks = us / (1000000 / HZ);
if (ticks > 0)
schedule_timeout_interruptible(1 + ticks);
else
udelay(us);
}
/*
* Start receiver by submitting a request to the receive pipe.
* If nothing is available it will return after rx_interval.
*/
static int receive_start(struct stir_cb *stir)
{
/* reset state */
stir->receiving = 1;
stir->rx_buff.in_frame = FALSE;
stir->rx_buff.state = OUTSIDE_FRAME;
stir->rx_urb->status = 0;
return usb_submit_urb(stir->rx_urb, GFP_KERNEL);
}
/* Stop all pending receive Urb's */
static void receive_stop(struct stir_cb *stir)
{
stir->receiving = 0;
usb_kill_urb(stir->rx_urb);
if (stir->rx_buff.in_frame)
stir->netdev->stats.collisions++;
}
/*
* Wrap data in socket buffer and send it.
*/
static void stir_send(struct stir_cb *stir, struct sk_buff *skb)
{
unsigned wraplen;
int first_frame = 0;
/* if receiving, need to turnaround */
if (stir->receiving) {
receive_stop(stir);
turnaround_delay(stir, irda_get_mtt(skb));
first_frame = 1;
}
if (isfir(stir->speed))
wraplen = wrap_fir_skb(skb, stir->io_buf);
else
wraplen = wrap_sir_skb(skb, stir->io_buf);
/* check for space available in fifo */
if (!first_frame)
fifo_txwait(stir, wraplen);
stir->netdev->stats.tx_packets++;
stir->netdev->stats.tx_bytes += skb->len;
netif_trans_update(stir->netdev);
pr_debug("send %d (%d)\n", skb->len, wraplen);
if (usb_bulk_msg(stir->usbdev, usb_sndbulkpipe(stir->usbdev, 1),
stir->io_buf, wraplen,
NULL, TRANSMIT_TIMEOUT))
stir->netdev->stats.tx_errors++;
}
/*
* Transmit state machine thread
*/
static int stir_transmit_thread(void *arg)
{
struct stir_cb *stir = arg;
struct net_device *dev = stir->netdev;
struct sk_buff *skb;
while (!kthread_should_stop()) {
#ifdef CONFIG_PM
/* if suspending, then power off and wait */
if (unlikely(freezing(current))) {
if (stir->receiving)
receive_stop(stir);
else
fifo_txwait(stir, -1);
write_reg(stir, REG_CTRL1, CTRL1_TXPWD|CTRL1_RXPWD);
try_to_freeze();
if (change_speed(stir, stir->speed))
break;
}
#endif
/* if something to send? */
skb = xchg(&stir->tx_pending, NULL);
if (skb) {
unsigned new_speed = irda_get_next_speed(skb);
netif_wake_queue(dev);
if (skb->len > 0)
stir_send(stir, skb);
dev_kfree_skb(skb);
if ((new_speed != -1) && (stir->speed != new_speed)) {
if (fifo_txwait(stir, -1) ||
change_speed(stir, new_speed))
break;
}
continue;
}
/* nothing to send? start receiving */
if (!stir->receiving &&
irda_device_txqueue_empty(dev)) {
/* Wait otherwise chip gets confused. */
if (fifo_txwait(stir, -1))
break;
if (unlikely(receive_start(stir))) {
if (net_ratelimit())
dev_info(&dev->dev,
"%s: receive usb submit failed\n",
stir->netdev->name);
stir->receiving = 0;
msleep(10);
continue;
}
}
/* sleep if nothing to send */
set_current_state(TASK_INTERRUPTIBLE);
schedule();
}
return 0;
}
/*
* USB bulk receive completion callback.
* Wakes up every ms (usb round trip) with wrapped
* data.
*/
static void stir_rcv_irq(struct urb *urb)
{
struct stir_cb *stir = urb->context;
int err;
/* in process of stopping, just drop data */
if (!netif_running(stir->netdev))
return;
/* unlink, shutdown, unplug, other nasties */
if (urb->status != 0)
return;
if (urb->actual_length > 0) {
pr_debug("receive %d\n", urb->actual_length);
unwrap_chars(stir, urb->transfer_buffer,
urb->actual_length);
stir->rx_time = ktime_get();
}
/* kernel thread is stopping receiver don't resubmit */
if (!stir->receiving)
return;
/* resubmit existing urb */
err = usb_submit_urb(urb, GFP_ATOMIC);
/* in case of error, the kernel thread will restart us */
if (err) {
dev_warn(&stir->netdev->dev, "usb receive submit error: %d\n",
err);
stir->receiving = 0;
wake_up_process(stir->thread);
}
}
/*
* Function stir_net_open (dev)
*
* Network device is taken up. Usually this is done by "ifconfig irda0 up"
*/
static int stir_net_open(struct net_device *netdev)
{
struct stir_cb *stir = netdev_priv(netdev);
int err;
char hwname[16];
err = usb_clear_halt(stir->usbdev, usb_sndbulkpipe(stir->usbdev, 1));
if (err)
goto err_out1;
err = usb_clear_halt(stir->usbdev, usb_rcvbulkpipe(stir->usbdev, 2));
if (err)
goto err_out1;
err = change_speed(stir, 9600);
if (err)
goto err_out1;
err = -ENOMEM;
/* Initialize for SIR/FIR to copy data directly into skb. */
stir->receiving = 0;
stir->rx_buff.truesize = IRDA_SKB_MAX_MTU;
stir->rx_buff.skb = dev_alloc_skb(IRDA_SKB_MAX_MTU);
if (!stir->rx_buff.skb)
goto err_out1;
skb_reserve(stir->rx_buff.skb, 1);
stir->rx_buff.head = stir->rx_buff.skb->data;
stir->rx_time = ktime_get();
stir->rx_urb = usb_alloc_urb(0, GFP_KERNEL);
if (!stir->rx_urb)
goto err_out2;
stir->io_buf = kmalloc(STIR_FIFO_SIZE, GFP_KERNEL);
if (!stir->io_buf)
goto err_out3;
usb_fill_bulk_urb(stir->rx_urb, stir->usbdev,
usb_rcvbulkpipe(stir->usbdev, 2),
stir->io_buf, STIR_FIFO_SIZE,
stir_rcv_irq, stir);
stir->fifo_status = kmalloc(FIFO_REGS_SIZE, GFP_KERNEL);
if (!stir->fifo_status)
goto err_out4;
/*
* Now that everything should be initialized properly,
* Open new IrLAP layer instance to take care of us...
* Note : will send immediately a speed change...
*/
sprintf(hwname, "usb#%d", stir->usbdev->devnum);
stir->irlap = irlap_open(netdev, &stir->qos, hwname);
if (!stir->irlap) {
dev_err(&stir->usbdev->dev, "irlap_open failed\n");
goto err_out5;
}
/** Start kernel thread for transmit. */
stir->thread = kthread_run(stir_transmit_thread, stir,
"%s", stir->netdev->name);
if (IS_ERR(stir->thread)) {
err = PTR_ERR(stir->thread);
dev_err(&stir->usbdev->dev, "unable to start kernel thread\n");
goto err_out6;
}
netif_start_queue(netdev);
return 0;
err_out6:
irlap_close(stir->irlap);
err_out5:
kfree(stir->fifo_status);
err_out4:
kfree(stir->io_buf);
err_out3:
usb_free_urb(stir->rx_urb);
err_out2:
kfree_skb(stir->rx_buff.skb);
err_out1:
return err;
}
/*
* Function stir_net_close (stir)
*
* Network device is taken down. Usually this is done by
* "ifconfig irda0 down"
*/
static int stir_net_close(struct net_device *netdev)
{
struct stir_cb *stir = netdev_priv(netdev);
/* Stop transmit processing */
netif_stop_queue(netdev);
/* Kill transmit thread */
kthread_stop(stir->thread);
kfree(stir->fifo_status);
/* Mop up receive urb's */
usb_kill_urb(stir->rx_urb);
kfree(stir->io_buf);
usb_free_urb(stir->rx_urb);
kfree_skb(stir->rx_buff.skb);
/* Stop and remove instance of IrLAP */
if (stir->irlap)
irlap_close(stir->irlap);
stir->irlap = NULL;
return 0;
}
/*
* IOCTLs : Extra out-of-band network commands...
*/
static int stir_net_ioctl(struct net_device *netdev, struct ifreq *rq, int cmd)
{
struct if_irda_req *irq = (struct if_irda_req *) rq;
struct stir_cb *stir = netdev_priv(netdev);
int ret = 0;
switch (cmd) {
case SIOCSBANDWIDTH: /* Set bandwidth */
if (!capable(CAP_NET_ADMIN))
return -EPERM;
/* Check if the device is still there */
if (netif_device_present(stir->netdev))
ret = change_speed(stir, irq->ifr_baudrate);
break;
case SIOCSMEDIABUSY: /* Set media busy */
if (!capable(CAP_NET_ADMIN))
return -EPERM;
/* Check if the IrDA stack is still there */
if (netif_running(stir->netdev))
irda_device_set_media_busy(stir->netdev, TRUE);
break;
case SIOCGRECEIVING:
/* Only approximately true */
irq->ifr_receiving = stir->receiving;
break;
default:
ret = -EOPNOTSUPP;
}
return ret;
}
static const struct net_device_ops stir_netdev_ops = {
.ndo_open = stir_net_open,
.ndo_stop = stir_net_close,
.ndo_start_xmit = stir_hard_xmit,
.ndo_do_ioctl = stir_net_ioctl,
};
/*
* This routine is called by the USB subsystem for each new device
* in the system. We need to check if the device is ours, and in
* this case start handling it.
* Note : it might be worth protecting this function by a global
* spinlock... Or not, because maybe USB already deal with that...
*/
static int stir_probe(struct usb_interface *intf,
const struct usb_device_id *id)
{
struct usb_device *dev = interface_to_usbdev(intf);
struct stir_cb *stir = NULL;
struct net_device *net;
int ret = -ENOMEM;
/* Allocate network device container. */
net = alloc_irdadev(sizeof(*stir));
if(!net)
goto err_out1;
SET_NETDEV_DEV(net, &intf->dev);
stir = netdev_priv(net);
stir->netdev = net;
stir->usbdev = dev;
ret = usb_reset_configuration(dev);
if (ret != 0) {
dev_err(&intf->dev, "usb reset configuration failed\n");
goto err_out2;
}
printk(KERN_INFO "SigmaTel STIr4200 IRDA/USB found at address %d, "
"Vendor: %x, Product: %x\n",
dev->devnum, le16_to_cpu(dev->descriptor.idVendor),
le16_to_cpu(dev->descriptor.idProduct));
/* Initialize QoS for this device */
irda_init_max_qos_capabilies(&stir->qos);
/* That's the Rx capability. */
stir->qos.baud_rate.bits &= IR_2400 | IR_9600 | IR_19200 |
IR_38400 | IR_57600 | IR_115200 |
(IR_4000000 << 8);
stir->qos.min_turn_time.bits &= qos_mtt_bits;
irda_qos_bits_to_value(&stir->qos);
/* Override the network functions we need to use */
net->netdev_ops = &stir_netdev_ops;
ret = register_netdev(net);
if (ret != 0)
goto err_out2;
dev_info(&intf->dev, "IrDA: Registered SigmaTel device %s\n",
net->name);
usb_set_intfdata(intf, stir);
return 0;
err_out2:
free_netdev(net);
err_out1:
return ret;
}
/*
* The current device is removed, the USB layer tell us to shut it down...
*/
static void stir_disconnect(struct usb_interface *intf)
{
struct stir_cb *stir = usb_get_intfdata(intf);
if (!stir)
return;
unregister_netdev(stir->netdev);
free_netdev(stir->netdev);
usb_set_intfdata(intf, NULL);
}
#ifdef CONFIG_PM
/* USB suspend, so power off the transmitter/receiver */
static int stir_suspend(struct usb_interface *intf, pm_message_t message)
{
struct stir_cb *stir = usb_get_intfdata(intf);
netif_device_detach(stir->netdev);
return 0;
}
/* Coming out of suspend, so reset hardware */
static int stir_resume(struct usb_interface *intf)
{
struct stir_cb *stir = usb_get_intfdata(intf);
netif_device_attach(stir->netdev);
/* receiver restarted when send thread wakes up */
return 0;
}
#endif
/*
* USB device callbacks
*/
static struct usb_driver irda_driver = {
.name = "stir4200",
.probe = stir_probe,
.disconnect = stir_disconnect,
.id_table = dongles,
#ifdef CONFIG_PM
.suspend = stir_suspend,
.resume = stir_resume,
#endif
};
module_usb_driver(irda_driver);
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