File-copy from v4.4.100

This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Please refer to that tree for all history prior to this point.

Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/net/irda/irda_device.c b/net/irda/irda_device.c
new file mode 100644
index 0000000..8567366
--- /dev/null
+++ b/net/irda/irda_device.c
@@ -0,0 +1,316 @@
+/*********************************************************************
+ *
+ * Filename:      irda_device.c
+ * Version:       0.9
+ * Description:   Utility functions used by the device drivers
+ * Status:        Experimental.
+ * Author:        Dag Brattli <dagb@cs.uit.no>
+ * Created at:    Sat Oct  9 09:22:27 1999
+ * Modified at:   Sun Jan 23 17:41:24 2000
+ * Modified by:   Dag Brattli <dagb@cs.uit.no>
+ *
+ *     Copyright (c) 1999-2000 Dag Brattli, All Rights Reserved.
+ *     Copyright (c) 2000-2001 Jean Tourrilhes <jt@hpl.hp.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.
+ *
+ *     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, see <http://www.gnu.org/licenses/>.
+ *
+ ********************************************************************/
+
+#include <linux/string.h>
+#include <linux/proc_fs.h>
+#include <linux/skbuff.h>
+#include <linux/capability.h>
+#include <linux/if.h>
+#include <linux/if_ether.h>
+#include <linux/if_arp.h>
+#include <linux/netdevice.h>
+#include <linux/init.h>
+#include <linux/tty.h>
+#include <linux/kmod.h>
+#include <linux/spinlock.h>
+#include <linux/slab.h>
+#include <linux/export.h>
+
+#include <asm/ioctls.h>
+#include <asm/uaccess.h>
+#include <asm/dma.h>
+#include <asm/io.h>
+
+#include <net/irda/irda_device.h>
+#include <net/irda/irlap.h>
+#include <net/irda/timer.h>
+#include <net/irda/wrapper.h>
+
+static void __irda_task_delete(struct irda_task *task);
+
+static hashbin_t *dongles = NULL;
+static hashbin_t *tasks = NULL;
+
+static void irda_task_timer_expired(void *data);
+
+int __init irda_device_init( void)
+{
+	dongles = hashbin_new(HB_NOLOCK);
+	if (dongles == NULL) {
+		net_warn_ratelimited("IrDA: Can't allocate dongles hashbin!\n");
+		return -ENOMEM;
+	}
+	spin_lock_init(&dongles->hb_spinlock);
+
+	tasks = hashbin_new(HB_LOCK);
+	if (tasks == NULL) {
+		net_warn_ratelimited("IrDA: Can't allocate tasks hashbin!\n");
+		hashbin_delete(dongles, NULL);
+		return -ENOMEM;
+	}
+
+	/* We no longer initialise the driver ourselves here, we let
+	 * the system do it for us... - Jean II */
+
+	return 0;
+}
+
+static void leftover_dongle(void *arg)
+{
+	struct dongle_reg *reg = arg;
+	net_warn_ratelimited("IrDA: Dongle type %x not unregistered\n",
+			     reg->type);
+}
+
+void irda_device_cleanup(void)
+{
+	hashbin_delete(tasks, (FREE_FUNC) __irda_task_delete);
+
+	hashbin_delete(dongles, leftover_dongle);
+}
+
+/*
+ * Function irda_device_set_media_busy (self, status)
+ *
+ *    Called when we have detected that another station is transmitting
+ *    in contention mode.
+ */
+void irda_device_set_media_busy(struct net_device *dev, int status)
+{
+	struct irlap_cb *self;
+
+	pr_debug("%s(%s)\n", __func__, status ? "TRUE" : "FALSE");
+
+	self = (struct irlap_cb *) dev->atalk_ptr;
+
+	/* Some drivers may enable the receive interrupt before calling
+	 * irlap_open(), or they may disable the receive interrupt
+	 * after calling irlap_close().
+	 * The IrDA stack is protected from this in irlap_driver_rcv().
+	 * However, the driver calls directly the wrapper, that calls
+	 * us directly. Make sure we protect ourselves.
+	 * Jean II */
+	if (!self || self->magic != LAP_MAGIC)
+		return;
+
+	if (status) {
+		self->media_busy = TRUE;
+		if (status == SMALL)
+			irlap_start_mbusy_timer(self, SMALLBUSY_TIMEOUT);
+		else
+			irlap_start_mbusy_timer(self, MEDIABUSY_TIMEOUT);
+		pr_debug("Media busy!\n");
+	} else {
+		self->media_busy = FALSE;
+		irlap_stop_mbusy_timer(self);
+	}
+}
+EXPORT_SYMBOL(irda_device_set_media_busy);
+
+
+/*
+ * Function irda_device_is_receiving (dev)
+ *
+ *    Check if the device driver is currently receiving data
+ *
+ */
+int irda_device_is_receiving(struct net_device *dev)
+{
+	struct if_irda_req req;
+	int ret;
+
+	if (!dev->netdev_ops->ndo_do_ioctl) {
+		net_err_ratelimited("%s: do_ioctl not impl. by device driver\n",
+				    __func__);
+		return -1;
+	}
+
+	ret = (dev->netdev_ops->ndo_do_ioctl)(dev, (struct ifreq *) &req,
+					      SIOCGRECEIVING);
+	if (ret < 0)
+		return ret;
+
+	return req.ifr_receiving;
+}
+
+static void __irda_task_delete(struct irda_task *task)
+{
+	del_timer(&task->timer);
+
+	kfree(task);
+}
+
+static void irda_task_delete(struct irda_task *task)
+{
+	/* Unregister task */
+	hashbin_remove(tasks, (long) task, NULL);
+
+	__irda_task_delete(task);
+}
+
+/*
+ * Function irda_task_kick (task)
+ *
+ *    Tries to execute a task possible multiple times until the task is either
+ *    finished, or askes for a timeout. When a task is finished, we do post
+ *    processing, and notify the parent task, that is waiting for this task
+ *    to complete.
+ */
+static int irda_task_kick(struct irda_task *task)
+{
+	int finished = TRUE;
+	int count = 0;
+	int timeout;
+
+	IRDA_ASSERT(task != NULL, return -1;);
+	IRDA_ASSERT(task->magic == IRDA_TASK_MAGIC, return -1;);
+
+	/* Execute task until it's finished, or askes for a timeout */
+	do {
+		timeout = task->function(task);
+		if (count++ > 100) {
+			net_err_ratelimited("%s: error in task handler!\n",
+					    __func__);
+			irda_task_delete(task);
+			return TRUE;
+		}
+	} while ((timeout == 0) && (task->state != IRDA_TASK_DONE));
+
+	if (timeout < 0) {
+		net_err_ratelimited("%s: Error executing task!\n", __func__);
+		irda_task_delete(task);
+		return TRUE;
+	}
+
+	/* Check if we are finished */
+	if (task->state == IRDA_TASK_DONE) {
+		del_timer(&task->timer);
+
+		/* Do post processing */
+		if (task->finished)
+			task->finished(task);
+
+		/* Notify parent */
+		if (task->parent) {
+			/* Check if parent is waiting for us to complete */
+			if (task->parent->state == IRDA_TASK_CHILD_WAIT) {
+				task->parent->state = IRDA_TASK_CHILD_DONE;
+
+				/* Stop timer now that we are here */
+				del_timer(&task->parent->timer);
+
+				/* Kick parent task */
+				irda_task_kick(task->parent);
+			}
+		}
+		irda_task_delete(task);
+	} else if (timeout > 0) {
+		irda_start_timer(&task->timer, timeout, (void *) task,
+				 irda_task_timer_expired);
+		finished = FALSE;
+	} else {
+		pr_debug("%s(), not finished, and no timeout!\n",
+			 __func__);
+		finished = FALSE;
+	}
+
+	return finished;
+}
+
+/*
+ * Function irda_task_timer_expired (data)
+ *
+ *    Task time has expired. We now try to execute task (again), and restart
+ *    the timer if the task has not finished yet
+ */
+static void irda_task_timer_expired(void *data)
+{
+	struct irda_task *task;
+
+	task = data;
+
+	irda_task_kick(task);
+}
+
+/*
+ * Function irda_device_setup (dev)
+ *
+ *    This function should be used by low level device drivers in a similar way
+ *    as ether_setup() is used by normal network device drivers
+ */
+static void irda_device_setup(struct net_device *dev)
+{
+	dev->hard_header_len = 0;
+	dev->addr_len        = LAP_ALEN;
+
+	dev->type            = ARPHRD_IRDA;
+	dev->tx_queue_len    = 8; /* Window size + 1 s-frame */
+
+	memset(dev->broadcast, 0xff, LAP_ALEN);
+
+	dev->mtu = 2048;
+	dev->flags = IFF_NOARP;
+}
+
+/*
+ * Funciton  alloc_irdadev
+ * 	Allocates and sets up an IRDA device in a manner similar to
+ * 	alloc_etherdev.
+ */
+struct net_device *alloc_irdadev(int sizeof_priv)
+{
+	return alloc_netdev(sizeof_priv, "irda%d", NET_NAME_UNKNOWN,
+			    irda_device_setup);
+}
+EXPORT_SYMBOL(alloc_irdadev);
+
+#ifdef CONFIG_ISA_DMA_API
+/*
+ * Function setup_dma (idev, buffer, count, mode)
+ *
+ *    Setup the DMA channel. Commonly used by LPC FIR drivers
+ *
+ */
+void irda_setup_dma(int channel, dma_addr_t buffer, int count, int mode)
+{
+	unsigned long flags;
+
+	flags = claim_dma_lock();
+
+	disable_dma(channel);
+	clear_dma_ff(channel);
+	set_dma_mode(channel, mode);
+	set_dma_addr(channel, buffer);
+	set_dma_count(channel, count);
+	enable_dma(channel);
+
+	release_dma_lock(flags);
+}
+EXPORT_SYMBOL(irda_setup_dma);
+#endif