ipwireless: driver for PC Card 3G/UMTS modem

The device is manufactured by IPWireless.  In some countries (for
example Czech Republic, T-Mobile ISP) this card is shipped for service
called UMTS 4G.

It's a piece of PCMCIA "4G" UMTS PPP networking hardware that presents
itself as a serial character device (i.e.  looks like usual modem to
userspace, accepts AT commands, etc).

Rewieved-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Ben Martel <benm@symmetric.co.nz>
Signed-off-by: Stephen Blackheath <stephen@symmetric.co.nz>
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 512 insertions, 0 deletions

diff --git a/drivers/char/pcmcia/ipwireless/network.c b/drivers/char/pcmcia/ipwireless/network.c
new file mode 100644
index 000000000000..ff35230058d3
--- /dev/null
+++ b/drivers/char/pcmcia/ipwireless/network.c
@@ -0,0 +1,512 @@
+/*
+ * IPWireless 3G PCMCIA Network Driver
+ *
+ * Original code
+ *   by Stephen Blackheath <stephen@blacksapphire.com>,
+ *      Ben Martel <benm@symmetric.co.nz>
+ *
+ * Copyrighted as follows:
+ *   Copyright (C) 2004 by Symmetric Systems Ltd (NZ)
+ *
+ * Various driver changes and rewrites, port to new kernels
+ *   Copyright (C) 2006-2007 Jiri Kosina
+ *
+ * Misc code cleanups and updates
+ *   Copyright (C) 2007 David Sterba
+ */
+
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/mutex.h>
+#include <linux/netdevice.h>
+#include <linux/ppp_channel.h>
+#include <linux/ppp_defs.h>
+#include <linux/if_ppp.h>
+#include <linux/skbuff.h>
+
+#include "network.h"
+#include "hardware.h"
+#include "main.h"
+#include "tty.h"
+
+#define MAX_OUTGOING_PACKETS_QUEUED   ipwireless_out_queue
+#define MAX_ASSOCIATED_TTYS 2
+
+#define SC_RCV_BITS     (SC_RCV_B7_1|SC_RCV_B7_0|SC_RCV_ODDP|SC_RCV_EVNP)
+
+struct ipw_network {
+	/* Hardware context, used for calls to hardware layer. */
+	struct ipw_hardware *hardware;
+	/* Context for kernel 'generic_ppp' functionality */
+	struct ppp_channel *ppp_channel;
+	/* tty context connected with IPW console */
+	struct ipw_tty *associated_ttys[NO_OF_IPW_CHANNELS][MAX_ASSOCIATED_TTYS];
+	/* True if ppp needs waking up once we're ready to xmit */
+	int ppp_blocked;
+	/* Number of packets queued up in hardware module. */
+	int outgoing_packets_queued;
+	/* Spinlock to avoid interrupts during shutdown */
+	spinlock_t spinlock;
+	struct mutex close_lock;
+
+	/* PPP ioctl data, not actually used anywere */
+	unsigned int flags;
+	unsigned int rbits;
+	u32 xaccm[8];
+	u32 raccm;
+	int mru;
+
+	int shutting_down;
+	unsigned int ras_control_lines;
+
+	struct work_struct work_go_online;
+	struct work_struct work_go_offline;
+};
+
+
+#ifdef IPWIRELESS_STATE_DEBUG
+int ipwireless_dump_network_state(char *p, size_t limit,
+				  struct ipw_network *network)
+{
+	return snprintf(p, limit,
+			"debug: ppp_blocked=%d\n"
+			"debug: outgoing_packets_queued=%d\n"
+			"debug: network.shutting_down=%d\n",
+			network->ppp_blocked,
+			network->outgoing_packets_queued,
+			network->shutting_down);
+}
+#endif
+
+static void notify_packet_sent(void *callback_data, unsigned int packet_length)
+{
+	struct ipw_network *network = callback_data;
+	unsigned long flags;
+
+	spin_lock_irqsave(&network->spinlock, flags);
+	network->outgoing_packets_queued--;
+	if (network->ppp_channel != NULL) {
+		if (network->ppp_blocked) {
+			network->ppp_blocked = 0;
+			spin_unlock_irqrestore(&network->spinlock, flags);
+			ppp_output_wakeup(network->ppp_channel);
+			if (ipwireless_debug)
+				printk(KERN_INFO IPWIRELESS_PCCARD_NAME
+				       ": ppp unblocked\n");
+		} else
+			spin_unlock_irqrestore(&network->spinlock, flags);
+	} else
+		spin_unlock_irqrestore(&network->spinlock, flags);
+}
+
+/*
+ * Called by the ppp system when it has a packet to send to the hardware.
+ */
+static int ipwireless_ppp_start_xmit(struct ppp_channel *ppp_channel,
+				     struct sk_buff *skb)
+{
+	struct ipw_network *network = ppp_channel->private;
+	unsigned long flags;
+
+	spin_lock_irqsave(&network->spinlock, flags);
+	if (network->outgoing_packets_queued < MAX_OUTGOING_PACKETS_QUEUED) {
+		unsigned char *buf;
+		static unsigned char header[] = {
+			PPP_ALLSTATIONS, /* 0xff */
+			PPP_UI,		 /* 0x03 */
+		};
+		int ret;
+
+		network->outgoing_packets_queued++;
+		spin_unlock_irqrestore(&network->spinlock, flags);
+
+		/*
+		 * If we have the requested amount of headroom in the skb we
+		 * were handed, then we can add the header efficiently.
+		 */
+		if (skb_headroom(skb) >= 2) {
+			memcpy(skb_push(skb, 2), header, 2);
+			ret = ipwireless_send_packet(network->hardware,
+					       IPW_CHANNEL_RAS, skb->data,
+					       skb->len,
+					       notify_packet_sent,
+					       network);
+			if (ret == -1) {
+				skb_pull(skb, 2);
+				return 0;
+			}
+		} else {
+			/* Otherwise (rarely) we do it inefficiently. */
+			buf = kmalloc(skb->len + 2, GFP_ATOMIC);
+			if (!buf)
+				return 0;
+			memcpy(buf + 2, skb->data, skb->len);
+			memcpy(buf, header, 2);
+			ret = ipwireless_send_packet(network->hardware,
+					       IPW_CHANNEL_RAS, buf,
+					       skb->len + 2,
+					       notify_packet_sent,
+					       network);
+			kfree(buf);
+			if (ret == -1)
+				return 0;
+		}
+		kfree_skb(skb);
+		return 1;
+	} else {
+		/*
+		 * Otherwise reject the packet, and flag that the ppp system
+		 * needs to be unblocked once we are ready to send.
+		 */
+		network->ppp_blocked = 1;
+		spin_unlock_irqrestore(&network->spinlock, flags);
+		return 0;
+	}
+}
+
+/* Handle an ioctl call that has come in via ppp. (copy of ppp_async_ioctl() */
+static int ipwireless_ppp_ioctl(struct ppp_channel *ppp_channel,
+				unsigned int cmd, unsigned long arg)
+{
+	struct ipw_network *network = ppp_channel->private;
+	int err, val;
+	u32 accm[8];
+	int __user *user_arg = (int __user *) arg;
+
+	err = -EFAULT;
+	switch (cmd) {
+	case PPPIOCGFLAGS:
+		val = network->flags | network->rbits;
+		if (put_user(val, user_arg))
+			break;
+		err = 0;
+		break;
+
+	case PPPIOCSFLAGS:
+		if (get_user(val, user_arg))
+			break;
+		network->flags = val & ~SC_RCV_BITS;
+		network->rbits = val & SC_RCV_BITS;
+		err = 0;
+		break;
+
+	case PPPIOCGASYNCMAP:
+		if (put_user(network->xaccm[0], user_arg))
+			break;
+		err = 0;
+		break;
+
+	case PPPIOCSASYNCMAP:
+		if (get_user(network->xaccm[0], user_arg))
+			break;
+		err = 0;
+		break;
+
+	case PPPIOCGRASYNCMAP:
+		if (put_user(network->raccm, user_arg))
+			break;
+		err = 0;
+		break;
+
+	case PPPIOCSRASYNCMAP:
+		if (get_user(network->raccm, user_arg))
+			break;
+		err = 0;
+		break;
+
+	case PPPIOCGXASYNCMAP:
+		if (copy_to_user((void __user *) arg, network->xaccm,
+					sizeof(network->xaccm)))
+			break;
+		err = 0;
+		break;
+
+	case PPPIOCSXASYNCMAP:
+		if (copy_from_user(accm, (void __user *) arg, sizeof(accm)))
+			break;
+		accm[2] &= ~0x40000000U;	/* can't escape 0x5e */
+		accm[3] |= 0x60000000U;	/* must escape 0x7d, 0x7e */
+		memcpy(network->xaccm, accm, sizeof(network->xaccm));
+		err = 0;
+		break;
+
+	case PPPIOCGMRU:
+		if (put_user(network->mru, user_arg))
+			break;
+		err = 0;
+		break;
+
+	case PPPIOCSMRU:
+		if (get_user(val, user_arg))
+			break;
+		if (val < PPP_MRU)
+			val = PPP_MRU;
+		network->mru = val;
+		err = 0;
+		break;
+
+	default:
+		err = -ENOTTY;
+	}
+
+	return err;
+}
+
+static struct ppp_channel_ops ipwireless_ppp_channel_ops = {
+	.start_xmit = ipwireless_ppp_start_xmit,
+	.ioctl      = ipwireless_ppp_ioctl
+};
+
+static void do_go_online(struct work_struct *work_go_online)
+{
+	struct ipw_network *network =
+		container_of(work_go_online, struct ipw_network,
+				work_go_online);
+	unsigned long flags;
+
+	spin_lock_irqsave(&network->spinlock, flags);
+	if (!network->ppp_channel) {
+		struct ppp_channel *channel;
+
+		spin_unlock_irqrestore(&network->spinlock, flags);
+		channel = kzalloc(sizeof(struct ppp_channel), GFP_KERNEL);
+		if (!channel) {
+			printk(KERN_ERR IPWIRELESS_PCCARD_NAME
+					": unable to allocate PPP channel\n");
+			return;
+		}
+		channel->private = network;
+		channel->mtu = 16384;	/* Wild guess */
+		channel->hdrlen = 2;
+		channel->ops = &ipwireless_ppp_channel_ops;
+
+		network->flags = 0;
+		network->rbits = 0;
+		network->mru = PPP_MRU;
+		memset(network->xaccm, 0, sizeof(network->xaccm));
+		network->xaccm[0] = ~0U;
+		network->xaccm[3] = 0x60000000U;
+		network->raccm = ~0U;
+		ppp_register_channel(channel);
+		spin_lock_irqsave(&network->spinlock, flags);
+		network->ppp_channel = channel;
+	}
+	spin_unlock_irqrestore(&network->spinlock, flags);
+}
+
+static void do_go_offline(struct work_struct *work_go_offline)
+{
+	struct ipw_network *network =
+		container_of(work_go_offline, struct ipw_network,
+				work_go_offline);
+	unsigned long flags;
+
+	mutex_lock(&network->close_lock);
+	spin_lock_irqsave(&network->spinlock, flags);
+	if (network->ppp_channel != NULL) {
+		struct ppp_channel *channel = network->ppp_channel;
+
+		network->ppp_channel = NULL;
+		spin_unlock_irqrestore(&network->spinlock, flags);
+		mutex_unlock(&network->close_lock);
+		ppp_unregister_channel(channel);
+	} else {
+		spin_unlock_irqrestore(&network->spinlock, flags);
+		mutex_unlock(&network->close_lock);
+	}
+}
+
+void ipwireless_network_notify_control_line_change(struct ipw_network *network,
+						   unsigned int channel_idx,
+						   unsigned int control_lines,
+						   unsigned int changed_mask)
+{
+	int i;
+
+	if (channel_idx == IPW_CHANNEL_RAS)
+		network->ras_control_lines = control_lines;
+
+	for (i = 0; i < MAX_ASSOCIATED_TTYS; i++) {
+		struct ipw_tty *tty =
+			network->associated_ttys[channel_idx][i];
+
+		/*
+		 * If it's associated with a tty (other than the RAS channel
+		 * when we're online), then send the data to that tty.  The RAS
+		 * channel's data is handled above - it always goes through
+		 * ppp_generic.
+		 */
+		if (tty)
+			ipwireless_tty_notify_control_line_change(tty,
+								  channel_idx,
+								  control_lines,
+								  changed_mask);
+	}
+}
+
+/*
+ * Some versions of firmware stuff packets with 0xff 0x03 (PPP: ALLSTATIONS, UI)
+ * bytes, which are required on sent packet, but not always present on received
+ * packets
+ */
+static struct sk_buff *ipw_packet_received_skb(unsigned char *data,
+					       unsigned int length)
+{
+	struct sk_buff *skb;
+
+	if (length > 2 && data[0] == PPP_ALLSTATIONS && data[1] == PPP_UI) {
+		length -= 2;
+		data += 2;
+	}
+
+	skb = dev_alloc_skb(length + 4);
+	skb_reserve(skb, 2);
+	memcpy(skb_put(skb, length), data, length);
+
+	return skb;
+}
+
+void ipwireless_network_packet_received(struct ipw_network *network,
+					unsigned int channel_idx,
+					unsigned char *data,
+					unsigned int length)
+{
+	int i;
+	unsigned long flags;
+
+	for (i = 0; i < MAX_ASSOCIATED_TTYS; i++) {
+		struct ipw_tty *tty = network->associated_ttys[channel_idx][i];
+
+		/*
+		 * If it's associated with a tty (other than the RAS channel
+		 * when we're online), then send the data to that tty.  The RAS
+		 * channel's data is handled above - it always goes through
+		 * ppp_generic.
+		 */
+		if (tty && channel_idx == IPW_CHANNEL_RAS
+				&& (network->ras_control_lines &
+					IPW_CONTROL_LINE_DCD) != 0
+				&& ipwireless_tty_is_modem(tty)) {
+			/*
+			 * If data came in on the RAS channel and this tty is
+			 * the modem tty, and we are online, then we send it to
+			 * the PPP layer.
+			 */
+			mutex_lock(&network->close_lock);
+			spin_lock_irqsave(&network->spinlock, flags);
+			if (network->ppp_channel != NULL) {
+				struct sk_buff *skb;
+
+				spin_unlock_irqrestore(&network->spinlock,
+						flags);
+
+				/* Send the data to the ppp_generic module. */
+				skb = ipw_packet_received_skb(data, length);
+				ppp_input(network->ppp_channel, skb);
+			} else
+				spin_unlock_irqrestore(&network->spinlock,
+						flags);
+			mutex_unlock(&network->close_lock);
+		}
+		/* Otherwise we send it out the tty. */
+		else
+			ipwireless_tty_received(tty, data, length);
+	}
+}
+
+struct ipw_network *ipwireless_network_create(struct ipw_hardware *hw)
+{
+	struct ipw_network *network =
+		kzalloc(sizeof(struct ipw_network), GFP_ATOMIC);
+
+	if (!network)
+		return NULL;
+
+	spin_lock_init(&network->spinlock);
+	mutex_init(&network->close_lock);
+
+	network->hardware = hw;
+
+	INIT_WORK(&network->work_go_online, do_go_online);
+	INIT_WORK(&network->work_go_offline, do_go_offline);
+
+	ipwireless_associate_network(hw, network);
+
+	return network;
+}
+
+void ipwireless_network_free(struct ipw_network *network)
+{
+	network->shutting_down = 1;
+
+	ipwireless_ppp_close(network);
+	flush_scheduled_work();
+
+	ipwireless_stop_interrupts(network->hardware);
+	ipwireless_associate_network(network->hardware, NULL);
+
+	kfree(network);
+}
+
+void ipwireless_associate_network_tty(struct ipw_network *network,
+				      unsigned int channel_idx,
+				      struct ipw_tty *tty)
+{
+	int i;
+
+	for (i = 0; i < MAX_ASSOCIATED_TTYS; i++)
+		if (network->associated_ttys[channel_idx][i] == NULL) {
+			network->associated_ttys[channel_idx][i] = tty;
+			break;
+		}
+}
+
+void ipwireless_disassociate_network_ttys(struct ipw_network *network,
+					  unsigned int channel_idx)
+{
+	int i;
+
+	for (i = 0; i < MAX_ASSOCIATED_TTYS; i++)
+		network->associated_ttys[channel_idx][i] = NULL;
+}
+
+void ipwireless_ppp_open(struct ipw_network *network)
+{
+	if (ipwireless_debug)
+		printk(KERN_DEBUG IPWIRELESS_PCCARD_NAME ": online\n");
+	schedule_work(&network->work_go_online);
+}
+
+void ipwireless_ppp_close(struct ipw_network *network)
+{
+	/* Disconnect from the wireless network. */
+	if (ipwireless_debug)
+		printk(KERN_DEBUG IPWIRELESS_PCCARD_NAME ": offline\n");
+	schedule_work(&network->work_go_offline);
+}
+
+int ipwireless_ppp_channel_index(struct ipw_network *network)
+{
+	int ret = -1;
+	unsigned long flags;
+
+	spin_lock_irqsave(&network->spinlock, flags);
+	if (network->ppp_channel != NULL)
+		ret = ppp_channel_index(network->ppp_channel);
+	spin_unlock_irqrestore(&network->spinlock, flags);
+
+	return ret;
+}
+
+int ipwireless_ppp_unit_number(struct ipw_network *network)
+{
+	int ret = -1;
+	unsigned long flags;
+
+	spin_lock_irqsave(&network->spinlock, flags);
+	if (network->ppp_channel != NULL)
+		ret = ppp_unit_number(network->ppp_channel);
+	spin_unlock_irqrestore(&network->spinlock, flags);
+
+	return ret;
+}