/*********************************************************************
*
* sir_dev.c: irda sir network device
*
* Copyright (c) 2002 Martin Diehl
*
* 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.
*
********************************************************************/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/smp_lock.h>
#include <linux/delay.h>
#include <net/irda/irda.h>
#include <net/irda/wrapper.h>
#include <net/irda/irda_device.h>
#include "sir-dev.h"
/***************************************************************************/
void sirdev_enable_rx(struct sir_dev *dev)
{
if (unlikely(atomic_read(&dev->enable_rx)))
return;
/* flush rx-buffer - should also help in case of problems with echo cancelation */
dev->rx_buff.data = dev->rx_buff.head;
dev->rx_buff.len = 0;
dev->rx_buff.in_frame = FALSE;
dev->rx_buff.state = OUTSIDE_FRAME;
atomic_set(&dev->enable_rx, 1);
}
static int sirdev_is_receiving(struct sir_dev *dev)
{
if (!atomic_read(&dev->enable_rx))
return 0;
return (dev->rx_buff.state != OUTSIDE_FRAME);
}
int sirdev_set_dongle(struct sir_dev *dev, IRDA_DONGLE type)
{
int err;
IRDA_DEBUG(3, "%s : requesting dongle %d.\n", __FUNCTION__, type);
err = sirdev_schedule_dongle_open(dev, type);
if (unlikely(err))
return err;
down(&dev->fsm.sem); /* block until config change completed */
err = dev->fsm.result;
up(&dev->fsm.sem);
return err;
}
/* used by dongle drivers for dongle programming */
int sirdev_raw_write(struct sir_dev *dev, const char *buf, int len)
{
unsigned long flags;
int ret;
if (unlikely(len > dev->tx_buff.truesize))
return -ENOSPC;
spin_lock_irqsave(&dev->tx_lock, flags); /* serialize with other tx operations */
while (dev->tx_buff.len > 0) { /* wait until tx idle */
spin_unlock_irqrestore(&dev->tx_lock, flags);
msleep(10);
spin_lock_irqsave(&dev->tx_lock, flags);
}
dev->tx_buff.data = dev->tx_buff.head;
memcpy(dev->tx_buff.data, buf, len);
dev->tx_buff.len = len;
ret = dev->drv->do_write(dev, dev->tx_buff.data, dev->tx_buff.len);
if (ret > 0) {
IRDA_DEBUG(3, "%s(), raw-tx started\n", __FUNCTION__);
dev->tx_buff.data += ret;
dev->tx_buff.len -= ret;
dev->raw_tx = 1;
ret = len; /* all data is going to be sent */
}
spin_unlock_irqrestore(&dev->tx_lock, flags);
return ret;
}
/* seems some dongle drivers may need this */
int sirdev_raw_read(struct sir_dev *dev, char *buf, int len)
{
int count;
if (atomic_read(&dev->enable_rx))
return -EIO; /* fail if we expect irda-frames */
count = (len < dev->rx_buff.len) ? len : dev->rx_buff.len;
if (count > 0) {
memcpy(buf, dev->rx_buff.data, count);
dev->rx_buff.data += count;
dev->rx_buff.len -= count;
}
/* remaining stuff gets flushed when re-enabling normal rx */
return count;
}
int sirdev_set_dtr_rts(struct sir_dev *dev, int dtr, int rts)
{
int ret = -ENXIO;
if (dev->drv->set_dtr_rts != 0)
ret = dev->drv->set_dtr_rts(dev, dtr, rts);
return ret;
}
/**********************************************************************/
/* called from client driver - likely with bh-context - to indicate
* it made some progress with transmission. Hence we send the next
* chunk, if any, or complete the skb otherwise
*/
void sirdev_write_complete(struct sir_dev *dev)
{
unsigned long flags;
struct sk_buff *skb;
int actual = 0;
int err;
spin_lock_irqsave(&dev->tx_lock, flags);
IRDA_DEBUG(3, "%s() - dev->tx_buff.len = %d\n",
__FUNCTION__, dev->tx_buff.len);
if (likely(dev->tx_buff.len > 0)) {
/* Write data left in transmit buffer */
actual = dev->drv->do_write(dev, dev->tx_buff.data, dev->tx_buff.len);
if (likely(actual>0)) {
dev->tx_buff.data += actual;
dev->tx_buff.len -= actual;
}
else if (unlikely(actual<0)) {
/* could be dropped later when we have tx_timeout to recover */
IRDA_ERROR("%s: drv->do_write failed (%d)\n",
__FUNCTION__, actual);
if ((skb=dev->tx_skb) != NULL) {
dev->tx_skb = NULL;
dev_kfree_skb_any(skb);
dev->stats.tx_errors++;
dev->stats.tx_dropped++;
}
dev->tx_buff.len = 0;
}
if (dev->tx_buff.len > 0)
goto done; /* more data to send later */
}
if (unlikely(dev->raw_tx != 0)) {
/* in raw mode we are just done now after the buffer was sent
* completely. Since this was requested by some dongle driver
* running under the control of the irda-thread we must take
* care here not to re-enable the queue. The queue will be
* restarted when the irda-thread has completed the request.
*/
IRDA_DEBUG(3, "%s(), raw-tx done\n", __FUNCTION__);
dev->raw_tx = 0;
goto done; /* no post-frame handling in raw mode */
}
/* we have finished now sending this skb.
* update statistics and free the skb.
* finally we check and trigger a pending speed change, if any.
* if not we switch to rx mode and wake the queue for further
* packets.
* note the scheduled speed request blocks until the lower
* client driver and the corresponding hardware has really
* finished sending all data (xmit fifo drained f.e.)
* before the speed change gets finally done and the queue
* re-activated.
*/
IRDA_DEBUG(5, "%s(), finished with frame!\n", __FUNCTION__);
if ((skb=dev->tx_skb) != NULL) {
dev->tx_skb = NULL;
dev->stats.tx_packets++;
dev->stats.tx_bytes += skb->len;
dev_kfree_skb_any(skb);
}
if (unlikely(dev->new_speed > 0)) {
IRDA_DEBUG(5, "%s(), Changing speed!\n", __FUNCTION__);
err = sirdev_schedule_speed(dev, dev->new_speed);
if (unlikely(err)) {
/* should never happen
* forget the speed change and hope the stack recovers
*/
IRDA_ERROR("%s - schedule speed change failed: %d\n",
__FUNCTION__, err);
netif_wake_queue(dev->netdev);
}
/* else: success
* speed change in progress now
* on completion dev->new_speed gets cleared,
* rx-reenabled and the queue restarted
*/
}
else {
sirdev_enable_rx(dev);
netif_wake_queue(dev->netdev);
}
done:
spin_unlock_irqrestore(&dev->tx_lock, flags);
}
/* called from client driver - likely with bh-context - to give us
* some more received bytes. We put them into the rx-buffer,
* normally unwrapping and building LAP-skb's (unless rx disabled)
*/
int sirdev_receive(struct sir_dev *dev, const unsigned char *cp, size_t count)
{
if (!dev || !dev->netdev) {
IRDA_WARNING("%s(), not ready yet!\n", __FUNCTION__);
return -1;
}
if (!dev->irlap) {
IRDA_WARNING("%s - too early: %p / %zd!\n",
__FUNCTION__, cp, count);
return -1;
}
if (cp==NULL) {
/* error already at lower level receive
* just update stats and set media busy
*/
irda_device_set_media_busy(dev->netdev, TRUE);
dev->stats.rx_dropped++;
IRDA_DEBUG(0, "%s; rx-drop: %zd\n", __FUNCTION__, count);
return 0;
}
/* Read the characters into the buffer */
if (likely(atomic_read(&dev->enable_rx))) {
while (count--)
/* Unwrap and destuff one byte */
async_unwrap_char(dev->netdev, &dev->stats,
&dev->rx_buff, *cp++);
} else {
while (count--) {
/* rx not enabled: save the raw bytes and never
* trigger any netif_rx. The received bytes are flushed
* later when we re-enable rx but might be read meanwhile
* by the dongle driver.
*/
dev->rx_buff.data[dev->rx_buff.len++] = *cp++;
/* What should we do when the buffer is full? */
if (unlikely(dev->rx_buff.len == dev->rx_buff.truesize))
dev->rx_buff.len = 0;
}
}
return 0;
}
/**********************************************************************/
/* callbacks from network layer */
static struct net_device_stats *sirdev_get_stats(struct net_device *ndev)
{
struct sir_dev *dev = ndev->priv;
return (dev) ? &dev->stats : NULL;
}
static int sirdev_hard_xmit(struct sk_buff *skb, struct net_device *ndev)
{
struct sir_dev *dev = ndev->priv;
unsigned long flags;
int actual = 0;
int err;
s32 speed;
IRDA_ASSERT(dev != NULL, return 0;);
netif_stop_queue(ndev);
IRDA_DEBUG(3, "%s(), skb->len = %d\n", __FUNCTION__, skb->len);
speed = irda_get_next_speed(skb);
if ((speed != dev->speed) && (speed != -1)) {
if (!skb->len) {
err = sirdev_schedule_speed(dev, speed);
if (unlikely(err == -EWOULDBLOCK)) {
/* Failed to initiate the speed change, likely the fsm
* is still busy (pretty unlikely, but...)
* We refuse to accept the skb and return with the queue
* stopped so the network layer will retry after the
* fsm completes and wakes the queue.
*/
return 1;
}
else if (unlikely(err)) {
/* other fatal error - forget the speed change and
* hope the stack will recover somehow
*/
netif_start_queue(ndev);
}
/* else: success
* speed change in progress now
* on completion the queue gets restarted
*/
dev_kfree_skb_any(skb);
return 0;
} else
dev->new_speed = speed;
}
/* Init tx buffer*/
dev->tx_buff.data = dev->tx_buff.head;
/* Check problems */
if(spin_is_locked(&dev->tx_lock)) {
IRDA_DEBUG(3, "%s(), write not completed\n", __FUNCTION__);
}
/* serialize with write completion */
spin_lock_irqsave(&dev->tx_lock, flags);
/* Copy skb to tx_buff while wrapping, stuffing and making CRC */
dev->tx_buff.len = async_wrap_skb(skb, dev->tx_buff.data, dev->tx_buff.truesize);
/* transmission will start now - disable receive.
* if we are just in the middle of an incoming frame,
* treat it as collision. probably it's a good idea to
* reset the rx_buf OUTSIDE_FRAME in this case too?
*/
atomic_set(&dev->enable_rx, 0);
if (unlikely(sirdev_is_receiving(dev)))
dev->stats.collisions++;
actual = dev->drv->do_write(dev, dev->tx_buff.data, dev->tx_buff.len);
if (likely(actual > 0)) {
dev->tx_skb = skb;
ndev->trans_start = jiffies;
dev->tx_buff.data += actual;
dev->tx_buff.len -= actual;
}
else if (unlikely(actual < 0)) {
/* could be dropped later when we have tx_timeout to recover */
IRDA_ERROR("%s: drv->do_write failed (%d)\n",
__FUNCTION__, actual);
dev_kfree_skb_any(skb);
dev->stats.tx_errors++;
dev->stats.tx_dropped++;
netif_wake_queue(ndev);
}
spin_unlock_irqrestore(&dev->tx_lock, flags);
return 0;
}
/* called from network layer with rtnl hold */
static int sirdev_ioctl(struct net_device *ndev, struct ifreq *rq, int cmd)
{
struct if_irda_req *irq = (struct if_irda_req *) rq;
struct sir_dev *dev = ndev->priv;
int ret = 0;
IRDA_ASSERT(dev != NULL, return -1;);
IRDA_DEBUG(3, "%s(), %s, (cmd=0x%X)\n", __FUNCTION__, ndev->name, cmd);
switch (cmd) {
case SIOCSBANDWIDTH: /* Set bandwidth */
if (!capable(CAP_NET_ADMIN))
ret = -EPERM;
else
ret = sirdev_schedule_speed(dev, irq->ifr_baudrate);
/* cannot sleep here for completion
* we are called from network layer with rtnl hold
*/
break;
case SIOCSDONGLE: /* Set dongle */
if (!capable(CAP_NET_ADMIN))
ret = -EPERM;
else
ret = sirdev_schedule_dongle_open(dev, irq->ifr_dongle);
/* cannot sleep here for completion
* we are called from network layer with rtnl hold
*/
break;
case SIOCSMEDIABUSY: /* Set media busy */
if (!capable(CAP_NET_ADMIN))
ret = -EPERM;
else
irda_device_set_media_busy(dev->netdev, TRUE);
break;
case SIOCGRECEIVING: /* Check if we are receiving right now */
irq->ifr_receiving = sirdev_is_receiving(dev);
break;
case SIOCSDTRRTS:
if (!capable(CAP_NET_ADMIN))
ret = -EPERM;
else
ret = sirdev_schedule_dtr_rts(dev, irq->ifr_dtr, irq->ifr_rts);
/* cannot sleep here for completion
* we are called from network layer with rtnl hold
*/
break;
case SIOCSMODE:
#if 0
if (!capable(CAP_NET_ADMIN))
ret = -EPERM;
else
ret = sirdev_schedule_mode(dev, irq->ifr_mode);
/* cannot sleep here for completion
* we are called from network layer with rtnl hold
*/
break;
#endif
default:
ret = -EOPNOTSUPP;
}
return ret;
}
/* ----------------------------------------------------------------------------- */
#define SIRBUF_ALLOCSIZE 4269 /* worst case size of a wrapped IrLAP frame */
static int sirdev_alloc_buffers(struct sir_dev *dev)
{
dev->tx_buff.truesize = SIRBUF_ALLOCSIZE;
dev->rx_buff.truesize = IRDA_SKB_MAX_MTU;
/* Bootstrap ZeroCopy Rx */
dev->rx_buff.skb = __dev_alloc_skb(dev->rx_buff.truesize, GFP_KERNEL);
if (dev->rx_buff.skb == NULL)
return -ENOMEM;
skb_reserve(dev->rx_buff.skb, 1);
dev->rx_buff.head = dev->rx_buff.skb->data;
dev->tx_buff.head = kmalloc(dev->tx_buff.truesize, GFP_KERNEL);
if (dev->tx_buff.head == NULL) {
kfree_skb(dev->rx_buff.skb);
dev->rx_buff.skb = NULL;
dev->rx_buff.head = NULL;
return -ENOMEM;
}
dev->tx_buff.data = dev->tx_buff.head;
dev->rx_buff.data = dev->rx_buff.head;
dev->tx_buff.len = 0;
dev->rx_buff.len = 0;
dev->rx_buff.in_frame = FALSE;
dev->rx_buff.state = OUTSIDE_FRAME;
return 0;
};
static void sirdev_free_buffers(struct sir_dev *dev)
{
if (dev->rx_buff.skb)
kfree_skb(dev->rx_buff.skb);
kfree(dev->tx_buff.head);
dev->rx_buff.head = dev->tx_buff.head = NULL;
dev->rx_buff.skb = NULL;
}
static int sirdev_open(struct net_device *ndev)
{
struct sir_dev *dev = ndev->priv;
const struct sir_driver *drv = dev->drv;
if (!drv)
return -ENODEV;
/* increase the reference count of the driver module before doing serious stuff */
if (!try_module_get(drv->owner))
return -ESTALE;
IRDA_DEBUG(2, "%s()\n", __FUNCTION__);
if (sirdev_alloc_buffers(dev))
goto errout_dec;
if (!dev->drv->start_dev || dev->drv->start_dev(dev))
goto errout_free;
sirdev_enable_rx(dev);
dev->raw_tx = 0;
netif_start_queue(ndev);
dev->irlap = irlap_open(ndev, &dev->qos, dev->hwname);
if (!dev->irlap)
goto errout_stop;
netif_wake_queue(ndev);
IRDA_DEBUG(2, "%s - done, speed = %d\n", __FUNCTION__, dev->speed);
return 0;
errout_stop:
atomic_set(&dev->enable_rx, 0);
if (dev->drv->stop_dev)
dev->drv->stop_dev(dev);
errout_free:
sirdev_free_buffers(dev);
errout_dec:
module_put(drv->owner);
return -EAGAIN;
}
static int sirdev_close(struct net_device *ndev)
{
struct sir_dev *dev = ndev->priv;
const struct sir_driver *drv;
// IRDA_DEBUG(0, "%s\n", __FUNCTION__);
netif_stop_queue(ndev);
down(&dev->fsm.sem); /* block on pending config completion */
atomic_set(&dev->enable_rx, 0);
if (unlikely(!dev->irlap))
goto out;
irlap_close(dev->irlap);
dev->irlap = NULL;
drv = dev->drv;
if (unlikely(!drv || !dev->priv))
goto out;
if (drv->stop_dev)
drv->stop_dev(dev);
sirdev_free_buffers(dev);
module_put(drv->owner);
out:
dev->speed = 0;
up(&dev->fsm.sem);
return 0;
}
/* ----------------------------------------------------------------------------- */
struct sir_dev * sirdev_get_instance(const struct sir_driver *drv, const char *name)
{
struct net_device *ndev;
struct sir_dev *dev;
IRDA_DEBUG(0, "%s - %s\n", __FUNCTION__, name);
/* instead of adding tests to protect against drv->do_write==NULL
* at several places we refuse to create a sir_dev instance for
* drivers which don't implement do_write.
*/
if (!drv || !drv->do_write)
return NULL;
/*
* Allocate new instance of the device
*/
ndev = alloc_irdadev(sizeof(*dev));
if (ndev == NULL) {
IRDA_ERROR("%s - Can't allocate memory for IrDA control block!\n", __FUNCTION__);
goto out;
}
dev = ndev->priv;
irda_init_max_qos_capabilies(&dev->qos);
dev->qos.baud_rate.bits = IR_9600|IR_19200|IR_38400|IR_57600|IR_115200;
dev->qos.min_turn_time.bits = drv->qos_mtt_bits;
irda_qos_bits_to_value(&dev->qos);
strncpy(dev->hwname, name, sizeof(dev->hwname)-1);
atomic_set(&dev->enable_rx, 0);
dev->tx_skb = NULL;
spin_lock_init(&dev->tx_lock);
init_MUTEX(&dev->fsm.sem);
INIT_LIST_HEAD(&dev->fsm.rq.lh_request);
dev->fsm.rq.pending = 0;
init_timer(&dev->fsm.rq.timer);
dev->drv = drv;
dev->netdev = ndev;
SET_MODULE_OWNER(ndev);
/* Override the network functions we need to use */
ndev->hard_start_xmit = sirdev_hard_xmit;
ndev->open = sirdev_open;
ndev->stop = sirdev_close;
ndev->get_stats = sirdev_get_stats;
ndev->do_ioctl = sirdev_ioctl;
if (register_netdev(ndev)) {
IRDA_ERROR("%s(), register_netdev() failed!\n", __FUNCTION__);
goto out_freenetdev;
}
return dev;
out_freenetdev:
free_netdev(ndev);
out:
return NULL;
}
int sirdev_put_instance(struct sir_dev *dev)
{
int err = 0;
IRDA_DEBUG(0, "%s\n", __FUNCTION__);
atomic_set(&dev->enable_rx, 0);
netif_carrier_off(dev->netdev);
netif_device_detach(dev->netdev);
if (dev->dongle_drv)
err = sirdev_schedule_dongle_close(dev);
if (err)
IRDA_ERROR("%s - error %d\n", __FUNCTION__, err);
sirdev_close(dev->netdev);
down(&dev->fsm.sem);
dev->fsm.state = SIRDEV_STATE_DEAD; /* mark staled */
dev->dongle_drv = NULL;
dev->priv = NULL;
up(&dev->fsm.sem);
/* Remove netdevice */
unregister_netdev(dev->netdev);
free_netdev(dev->netdev);
return 0;
}
