Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 244 insertions, 0 deletions

diff --git a/drivers/w1/w1_int.c b/drivers/w1/w1_int.c
new file mode 100644
index 0000000000..3a71c5eb2f
--- /dev/null
+++ b/drivers/w1/w1_int.c
@@ -0,0 +1,244 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2004 Evgeniy Polyakov <zbr@ioremap.net>
+ */
+
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/delay.h>
+#include <linux/kthread.h>
+#include <linux/slab.h>
+#include <linux/sched/signal.h>
+#include <linux/export.h>
+#include <linux/moduleparam.h>
+
+#include "w1_internal.h"
+#include "w1_netlink.h"
+
+static int w1_search_count = -1; /* Default is continual scan */
+module_param_named(search_count, w1_search_count, int, 0);
+
+static int w1_enable_pullup = 1;
+module_param_named(enable_pullup, w1_enable_pullup, int, 0);
+
+static struct w1_master *w1_alloc_dev(u32 id, int slave_count, int slave_ttl,
+				       struct device_driver *driver,
+				       struct device *device)
+{
+	struct w1_master *dev;
+	int err;
+
+	/*
+	 * We are in process context(kernel thread), so can sleep.
+	 */
+	dev = kzalloc(sizeof(struct w1_master) + sizeof(struct w1_bus_master), GFP_KERNEL);
+	if (!dev) {
+		pr_err("Failed to allocate %zd bytes for new w1 device.\n",
+			sizeof(struct w1_master));
+		return NULL;
+	}
+
+
+	dev->bus_master = (struct w1_bus_master *)(dev + 1);
+
+	dev->owner		= THIS_MODULE;
+	dev->max_slave_count	= slave_count;
+	dev->slave_count	= 0;
+	dev->attempts		= 0;
+	dev->initialized	= 0;
+	dev->id			= id;
+	dev->slave_ttl		= slave_ttl;
+	dev->search_count	= w1_search_count;
+	dev->enable_pullup	= w1_enable_pullup;
+
+	/* For __w1_remove_master_device to decrement
+	 */
+	atomic_set(&dev->refcnt, 1);
+
+	INIT_LIST_HEAD(&dev->slist);
+	INIT_LIST_HEAD(&dev->async_list);
+	mutex_init(&dev->mutex);
+	mutex_init(&dev->bus_mutex);
+	mutex_init(&dev->list_mutex);
+
+	memcpy(&dev->dev, device, sizeof(struct device));
+	dev_set_name(&dev->dev, "w1_bus_master%u", dev->id);
+	snprintf(dev->name, sizeof(dev->name), "w1_bus_master%u", dev->id);
+	dev->dev.init_name = dev->name;
+
+	dev->driver = driver;
+
+	dev->seq = 1;
+
+	err = device_register(&dev->dev);
+	if (err) {
+		pr_err("Failed to register master device. err=%d\n", err);
+		put_device(&dev->dev);
+		dev = NULL;
+	}
+
+	return dev;
+}
+
+static void w1_free_dev(struct w1_master *dev)
+{
+	device_unregister(&dev->dev);
+}
+
+/**
+ * w1_add_master_device() - registers a new master device
+ * @master:	master bus device to register
+ */
+int w1_add_master_device(struct w1_bus_master *master)
+{
+	struct w1_master *dev, *entry;
+	int retval = 0;
+	struct w1_netlink_msg msg;
+	int id, found;
+
+	/* validate minimum functionality */
+	if (!(master->touch_bit && master->reset_bus) &&
+	    !(master->write_bit && master->read_bit) &&
+	    !(master->write_byte && master->read_byte && master->reset_bus)) {
+		pr_err("w1_add_master_device: invalid function set\n");
+		return(-EINVAL);
+	}
+
+	/* Lock until the device is added (or not) to w1_masters. */
+	mutex_lock(&w1_mlock);
+	/* Search for the first available id (starting at 1). */
+	id = 0;
+	do {
+		++id;
+		found = 0;
+		list_for_each_entry(entry, &w1_masters, w1_master_entry) {
+			if (entry->id == id) {
+				found = 1;
+				break;
+			}
+		}
+	} while (found);
+
+	dev = w1_alloc_dev(id, w1_max_slave_count, w1_max_slave_ttl,
+		&w1_master_driver, &w1_master_device);
+	if (!dev) {
+		mutex_unlock(&w1_mlock);
+		return -ENOMEM;
+	}
+
+	retval =  w1_create_master_attributes(dev);
+	if (retval) {
+		mutex_unlock(&w1_mlock);
+		goto err_out_free_dev;
+	}
+
+	memcpy(dev->bus_master, master, sizeof(struct w1_bus_master));
+
+	dev->initialized = 1;
+
+	dev->thread = kthread_run(&w1_process, dev, "%s", dev->name);
+	if (IS_ERR(dev->thread)) {
+		retval = PTR_ERR(dev->thread);
+		dev_err(&dev->dev,
+			 "Failed to create new kernel thread. err=%d\n",
+			 retval);
+		mutex_unlock(&w1_mlock);
+		goto err_out_rm_attr;
+	}
+
+	list_add(&dev->w1_master_entry, &w1_masters);
+	mutex_unlock(&w1_mlock);
+
+	memset(&msg, 0, sizeof(msg));
+	msg.id.mst.id = dev->id;
+	msg.type = W1_MASTER_ADD;
+	w1_netlink_send(dev, &msg);
+
+	return 0;
+
+#if 0 /* Thread cleanup code, not required currently. */
+err_out_kill_thread:
+	set_bit(W1_ABORT_SEARCH, &dev->flags);
+	kthread_stop(dev->thread);
+#endif
+err_out_rm_attr:
+	w1_destroy_master_attributes(dev);
+err_out_free_dev:
+	w1_free_dev(dev);
+
+	return retval;
+}
+EXPORT_SYMBOL(w1_add_master_device);
+
+void __w1_remove_master_device(struct w1_master *dev)
+{
+	struct w1_netlink_msg msg;
+	struct w1_slave *sl, *sln;
+
+	mutex_lock(&w1_mlock);
+	list_del(&dev->w1_master_entry);
+	mutex_unlock(&w1_mlock);
+
+	set_bit(W1_ABORT_SEARCH, &dev->flags);
+	kthread_stop(dev->thread);
+
+	mutex_lock(&dev->mutex);
+	mutex_lock(&dev->list_mutex);
+	list_for_each_entry_safe(sl, sln, &dev->slist, w1_slave_entry) {
+		mutex_unlock(&dev->list_mutex);
+		w1_slave_detach(sl);
+		mutex_lock(&dev->list_mutex);
+	}
+	w1_destroy_master_attributes(dev);
+	mutex_unlock(&dev->list_mutex);
+	mutex_unlock(&dev->mutex);
+	atomic_dec(&dev->refcnt);
+
+	while (atomic_read(&dev->refcnt)) {
+		dev_info(&dev->dev, "Waiting for %s to become free: refcnt=%d.\n",
+				dev->name, atomic_read(&dev->refcnt));
+
+		if (msleep_interruptible(1000))
+			flush_signals(current);
+		mutex_lock(&dev->list_mutex);
+		w1_process_callbacks(dev);
+		mutex_unlock(&dev->list_mutex);
+	}
+	mutex_lock(&dev->list_mutex);
+	w1_process_callbacks(dev);
+	mutex_unlock(&dev->list_mutex);
+
+	memset(&msg, 0, sizeof(msg));
+	msg.id.mst.id = dev->id;
+	msg.type = W1_MASTER_REMOVE;
+	w1_netlink_send(dev, &msg);
+
+	w1_free_dev(dev);
+}
+
+/**
+ * w1_remove_master_device() - unregister a master device
+ * @bm:	master bus device to remove
+ */
+void w1_remove_master_device(struct w1_bus_master *bm)
+{
+	struct w1_master *dev, *found = NULL;
+
+	list_for_each_entry(dev, &w1_masters, w1_master_entry) {
+		if (!dev->initialized)
+			continue;
+
+		if (dev->bus_master->data == bm->data) {
+			found = dev;
+			break;
+		}
+	}
+
+	if (!found) {
+		pr_err("Device doesn't exist.\n");
+		return;
+	}
+
+	__w1_remove_master_device(found);
+}
+EXPORT_SYMBOL(w1_remove_master_device);