w1.c

Linux Kernel 2.6.9 for OMAP1710

/*
 * 	w1.c
 *
 * Copyright (c) 2004 Evgeniy Polyakov <[e-mail]>
 * 
 *
 * 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, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

#include <asm/atomic.h>

#include <linux/delay.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/list.h>
#include <linux/interrupt.h>
#include <linux/spinlock.h>
#include <linux/timer.h>
#include <linux/device.h>
#include <linux/slab.h>
#include <linux/sched.h>
#include <linux/suspend.h>

#include "w1.h"
#include "w1_io.h"
#include "w1_log.h"
#include "w1_int.h"
#include "w1_family.h"
#include "w1_netlink.h"

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Evgeniy Polyakov <[e-mail]>");
MODULE_DESCRIPTION("Driver for 1-wire Dallas network protocol.");

static int w1_timeout = 10;
int w1_max_slave_count = 10;

module_param_named(timeout, w1_timeout, int, 0);
module_param_named(max_slave_count, w1_max_slave_count, int, 0);

spinlock_t w1_mlock = SPIN_LOCK_UNLOCKED;
LIST_HEAD(w1_masters);

static pid_t control_thread;
static int control_needs_exit;
static DECLARE_COMPLETION(w1_control_complete);
static DECLARE_WAIT_QUEUE_HEAD(w1_control_wait);

static int w1_master_match(struct device *dev, struct device_driver *drv)
{
	return 1;
}

static int w1_master_probe(struct device *dev)
{
	return -ENODEV;
}

static int w1_master_remove(struct device *dev)
{
	return 0;
}

static void w1_master_release(struct device *dev)
{
	struct w1_master *md = container_of(dev, struct w1_master, dev);

	complete(&md->dev_released);
}

static void w1_slave_release(struct device *dev)
{
	struct w1_slave *sl = container_of(dev, struct w1_slave, dev);

	complete(&sl->dev_released);
}

static ssize_t w1_default_read_name(struct device *dev, char *buf)
{
	return sprintf(buf, "No family registered.\n");
}

static ssize_t w1_default_read_bin(struct kobject *kobj, char *buf, loff_t off,
		     size_t count)
{
	return sprintf(buf, "No family registered.\n");
}

struct bus_type w1_bus_type = {
	.name = "w1",
	.match = w1_master_match,
};

struct device_driver w1_driver = {
	.name = "w1_driver",
	.bus = &w1_bus_type,
	.probe = w1_master_probe,
	.remove = w1_master_remove,
};

struct device w1_device = {
	.parent = NULL,
	.bus = &w1_bus_type,
	.bus_id = "w1 bus master",
	.driver = &w1_driver,
	.release = &w1_master_release
};

static struct device_attribute w1_slave_attribute = {
	.attr = {
			.name = "name",
			.mode = S_IRUGO,
			.owner = THIS_MODULE
	},
	.show = &w1_default_read_name,
};

static struct device_attribute w1_slave_attribute_val = {
	.attr = {
			.name = "value",
			.mode = S_IRUGO,
			.owner = THIS_MODULE
	},
	.show = &w1_default_read_name,
};

ssize_t w1_master_attribute_show_name(struct device *dev, char *buf)
{
	struct w1_master *md = container_of (dev, struct w1_master, dev);
	ssize_t count;
	
	if (down_interruptible (&md->mutex))
		return -EBUSY;

	count = sprintf(buf, "%s\n", md->name);
	
	up(&md->mutex);

	return count;
}

ssize_t w1_master_attribute_show_pointer(struct device *dev, char *buf)
{
	struct w1_master *md = container_of(dev, struct w1_master, dev);
	ssize_t count;
	
	if (down_interruptible(&md->mutex))
		return -EBUSY;

	count = sprintf(buf, "0x%p\n", md->bus_master);
	
	up(&md->mutex);
	return count;
}

ssize_t w1_master_attribute_show_timeout(struct device *dev, char *buf)
{
	ssize_t count;
	count = sprintf(buf, "%d\n", w1_timeout);
	return count;
}

ssize_t w1_master_attribute_show_max_slave_count(struct device *dev, char *buf)
{
	struct w1_master *md = container_of(dev, struct w1_master, dev);
	ssize_t count;
	
	if (down_interruptible(&md->mutex))
		return -EBUSY;

	count = sprintf(buf, "%d\n", md->max_slave_count);
	
	up(&md->mutex);
	return count;
}

ssize_t w1_master_attribute_show_attempts(struct device *dev, char *buf)
{
	struct w1_master *md = container_of(dev, struct w1_master, dev);
	ssize_t count;
	
	if (down_interruptible(&md->mutex))
		return -EBUSY;

	count = sprintf(buf, "%lu\n", md->attempts);
	
	up(&md->mutex);
	return count;
}

ssize_t w1_master_attribute_show_slave_count(struct device *dev, char *buf)
{
	struct w1_master *md = container_of(dev, struct w1_master, dev);
	ssize_t count;
	
	if (down_interruptible(&md->mutex))
		return -EBUSY;

	count = sprintf(buf, "%d\n", md->slave_count);
	
	up(&md->mutex);
	return count;
}

ssize_t w1_master_attribute_show_slaves(struct device *dev, char *buf)

{
	struct w1_master *md = container_of(dev, struct w1_master, dev);
	int c = PAGE_SIZE;

	if (down_interruptible(&md->mutex))
		return -EBUSY;

	if (md->slave_count == 0)
		c -= snprintf(buf + PAGE_SIZE - c, c, "not found.\n");
	else {
		struct list_head *ent, *n;
		struct w1_slave *sl;

		list_for_each_safe(ent, n, &md->slist) {
			sl = list_entry(ent, struct w1_slave, w1_slave_entry);

 			c -= snprintf(buf + PAGE_SIZE - c, c, "%s\n", sl->name);
		}
	}

	up(&md->mutex);

	return PAGE_SIZE - c;
}

static struct device_attribute w1_master_attribute_slaves = {
	.attr = {
 			.name = "w1_master_slaves",
			.mode = S_IRUGO,
			.owner = THIS_MODULE,
	},
 	.show = &w1_master_attribute_show_slaves,
};
static struct device_attribute w1_master_attribute_slave_count = {
	.attr = {
			.name = "w1_master_slave_count",
			.mode = S_IRUGO,
			.owner = THIS_MODULE
	},
	.show = &w1_master_attribute_show_slave_count,
};
static struct device_attribute w1_master_attribute_attempts = {
	.attr = {
			.name = "w1_master_attempts",
			.mode = S_IRUGO,
			.owner = THIS_MODULE
	},
	.show = &w1_master_attribute_show_attempts,
};
static struct device_attribute w1_master_attribute_max_slave_count = {
	.attr = {
			.name = "w1_master_max_slave_count",
			.mode = S_IRUGO,
			.owner = THIS_MODULE
	},
	.show = &w1_master_attribute_show_max_slave_count,
};
static struct device_attribute w1_master_attribute_timeout = {
	.attr = {
			.name = "w1_master_timeout",
			.mode = S_IRUGO,
			.owner = THIS_MODULE
	},
	.show = &w1_master_attribute_show_timeout,
};
static struct device_attribute w1_master_attribute_pointer = {
	.attr = {
			.name = "w1_master_pointer",
			.mode = S_IRUGO,
			.owner = THIS_MODULE
	},
	.show = &w1_master_attribute_show_pointer,
};
static struct device_attribute w1_master_attribute_name = {
	.attr = {
			.name = "w1_master_name",
			.mode = S_IRUGO,
			.owner = THIS_MODULE
	},
	.show = &w1_master_attribute_show_name,
};

static struct bin_attribute w1_slave_bin_attribute = {
	.attr = {
		 	.name = "w1_slave",
		 	.mode = S_IRUGO,
			.owner = THIS_MODULE,
	},
	.size = W1_SLAVE_DATA_SIZE,
	.read = &w1_default_read_bin,
};

static int __w1_attach_slave_device(struct w1_slave *sl)
{
	int err;

	sl->dev.parent = &sl->master->dev;
	sl->dev.driver = sl->master->driver;
	sl->dev.bus = &w1_bus_type;
	sl->dev.release = &w1_slave_release;

	snprintf(&sl->dev.bus_id[0], sizeof(sl->dev.bus_id),
		  "%02x-%012llx",
		  (unsigned int) sl->reg_num.family,
		  (unsigned long long) sl->reg_num.id);
	snprintf (&sl->name[0], sizeof(sl->name),
		  "%02x-%012llx",
		  (unsigned int) sl->reg_num.family,
		  (unsigned long long) sl->reg_num.id);

	dev_dbg(&sl->dev, "%s: registering %s.\n", __func__,
		&sl->dev.bus_id[0]);

	err = device_register(&sl->dev);
	if (err < 0) {
		dev_err(&sl->dev,
			 "Device registration [%s] failed. err=%d\n",
			 sl->dev.bus_id, err);
		return err;
	}

	memcpy(&sl->attr_bin, &w1_slave_bin_attribute, sizeof(sl->attr_bin));
	memcpy(&sl->attr_name, &w1_slave_attribute, sizeof(sl->attr_name));
	memcpy(&sl->attr_val, &w1_slave_attribute_val, sizeof(sl->attr_val));
	
	sl->attr_bin.read = sl->family->fops->rbin;
	sl->attr_name.show = sl->family->fops->rname;
	sl->attr_val.show = sl->family->fops->rval;
	sl->attr_val.attr.name = sl->family->fops->rvalname;

	err = device_create_file(&sl->dev, &sl->attr_name);
	if (err < 0) {
		dev_err(&sl->dev,
			 "sysfs file creation for [%s] failed. err=%d\n",
			 sl->dev.bus_id, err);
		device_unregister(&sl->dev);
		return err;
	}

	err = device_create_file(&sl->dev, &sl->attr_val);
	if (err < 0) {
		dev_err(&sl->dev,
			 "sysfs file creation for [%s] failed. err=%d\n",
			 sl->dev.bus_id, err);
		device_remove_file(&sl->dev, &sl->attr_name);
		device_unregister(&sl->dev);
		return err;
	}

	err = sysfs_create_bin_file(&sl->dev.kobj, &sl->attr_bin);
	if (err < 0) {
		dev_err(&sl->dev,
			 "sysfs file creation for [%s] failed. err=%d\n",
			 sl->dev.bus_id, err);
		device_remove_file(&sl->dev, &sl->attr_name);
		device_remove_file(&sl->dev, &sl->attr_val);
		device_unregister(&sl->dev);
		return err;
	}

	list_add_tail(&sl->w1_slave_entry, &sl->master->slist);

	return 0;
}

static int w1_attach_slave_device(struct w1_master *dev, struct w1_reg_num *rn)
{
	struct w1_slave *sl;
	struct w1_family *f;
	int err;
	struct w1_netlink_msg msg;

	sl = kmalloc(sizeof(struct w1_slave), GFP_KERNEL);
	if (!sl) {
		dev_err(&dev->dev,
			 "%s: failed to allocate new slave device.\n",
			 __func__);
		return -ENOMEM;
	}

	memset(sl, 0, sizeof(*sl));