From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sat, 16 Apr 2005 15:20:36 -0700 Subject: Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip! --- drivers/w1/w1.c | 835 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 835 insertions(+) create mode 100644 drivers/w1/w1.c (limited to 'drivers/w1/w1.c') diff --git a/drivers/w1/w1.c b/drivers/w1/w1.c new file mode 100644 index 00000000000..fd630cec0e7 --- /dev/null +++ b/drivers/w1/w1.c @@ -0,0 +1,835 @@ +/* + * w1.c + * + * Copyright (c) 2004 Evgeniy Polyakov + * + * + * 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 +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include + +#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 "); +MODULE_DESCRIPTION("Driver for 1-wire Dallas network protocol."); + +static int w1_timeout = 10; +int w1_max_slave_count = 10; +int w1_max_slave_ttl = 10; + +module_param_named(timeout, w1_timeout, int, 0); +module_param_named(max_slave_count, w1_max_slave_count, int, 0); +module_param_named(slave_ttl, w1_max_slave_ttl, int, 0); + +DEFINE_SPINLOCK(w1_mlock); +LIST_HEAD(w1_masters); + +static pid_t control_thread; +static int control_needs_exit; +static DECLARE_COMPLETION(w1_control_complete); + +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"); +} + +static 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, +}; + +static 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; +} + +static 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; +} + +static ssize_t w1_master_attribute_show_timeout(struct device *dev, char *buf) +{ + ssize_t count; + count = sprintf(buf, "%d\n", w1_timeout); + return count; +} + +static 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; +} + +static 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; +} + +static 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; +} + +static 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)); + + sl->owner = THIS_MODULE; + sl->master = dev; + set_bit(W1_SLAVE_ACTIVE, (long *)&sl->flags); + + memcpy(&sl->reg_num, rn, sizeof(sl->reg_num)); + atomic_set(&sl->refcnt, 0); + init_completion(&sl->dev_released); + + spin_lock(&w1_flock); + f = w1_family_registered(rn->family); + if (!f) { + spin_unlock(&w1_flock); + dev_info(&dev->dev, "Family %x for %02x.%012llx.%02x is not registered.\n", + rn->family, rn->family, + (unsigned long long)rn->id, rn->crc); + kfree(sl); + return -ENODEV; + } + __w1_family_get(f); + spin_unlock(&w1_flock); + + sl->family = f; + + + err = __w1_attach_slave_device(sl); + if (err < 0) { + dev_err(&dev->dev, "%s: Attaching %s failed.\n", __func__, + sl->name); + w1_family_put(sl->family); + kfree(sl); + return err; + } + + sl->ttl = dev->slave_ttl; + dev->slave_count++; + + memcpy(&msg.id.id, rn, sizeof(msg.id.id)); + msg.type = W1_SLAVE_ADD; + w1_netlink_send(dev, &msg); + + return 0; +} + +static void w1_slave_detach(struct w1_slave *sl) +{ + struct w1_netlink_msg msg; + + dev_info(&sl->dev, "%s: detaching %s.\n", __func__, sl->name); + + while (atomic_read(&sl->refcnt)) { + printk(KERN_INFO "Waiting for %s to become free: refcnt=%d.\n", + sl->name, atomic_read(&sl->refcnt)); + + if (msleep_interruptible(1000)) + flush_signals(current); + } + + sysfs_remove_bin_file (&sl->dev.kobj, &sl->attr_bin); + device_remove_file(&sl->dev, &sl->attr_name); + device_remove_file(&sl->dev, &sl->attr_val); + device_unregister(&sl->dev); + w1_family_put(sl->family); + + memcpy(&msg.id.id, &sl->reg_num, sizeof(msg.id.id)); + msg.type = W1_SLAVE_REMOVE; + w1_netlink_send(sl->master, &msg); +} + +static struct w1_master *w1_search_master(unsigned long data) +{ + struct w1_master *dev; + int found = 0; + + spin_lock_irq(&w1_mlock); + list_for_each_entry(dev, &w1_masters, w1_master_entry) { + if (dev->bus_master->data == data) { + found = 1; + atomic_inc(&dev->refcnt); + break; + } + } + spin_unlock_irq(&w1_mlock); + + return (found)?dev:NULL; +} + +void w1_slave_found(unsigned long data, u64 rn) +{ + int slave_count; + struct w1_slave *sl; + struct list_head *ent; + struct w1_reg_num *tmp; + int family_found = 0; + struct w1_master *dev; + + dev = w1_search_master(data); + if (!dev) { + printk(KERN_ERR "Failed to find w1 master device for data %08lx, it is impossible.\n", + data); + return; + } + + tmp = (struct w1_reg_num *) &rn; + + slave_count = 0; + list_for_each(ent, &dev->slist) { + + sl = list_entry(ent, struct w1_slave, w1_slave_entry); + + if (sl->reg_num.family == tmp->family && + sl->reg_num.id == tmp->id && + sl->reg_num.crc == tmp->crc) { + set_bit(W1_SLAVE_ACTIVE, (long *)&sl->flags); + break; + } + else if (sl->reg_num.family == tmp->family) { + family_found = 1; + break; + } + + slave_count++; + } + + if (slave_count == dev->slave_count && rn ) { + tmp = cpu_to_le64(rn); + if(((rn >> 56) & 0xff) == w1_calc_crc8((u8 *)&tmp, 7)) + w1_attach_slave_device(dev, (struct w1_reg_num *) &rn); + } + + atomic_dec(&dev->refcnt); +} + +void w1_search(struct w1_master *dev) +{ + u64 last, rn, tmp; + int i, count = 0; + int last_family_desc, last_zero, last_device; + int search_bit, id_bit, comp_bit, desc_bit; + + search_bit = id_bit = comp_bit = 0; + rn = tmp = last = 0; + last_device = last_zero = last_family_desc = 0; + + desc_bit = 64; + + while (!(id_bit && comp_bit) && !last_device + && count++ < dev->max_slave_count) { + last = rn; + rn = 0; + + last_family_desc = 0; + + /* + * Reset bus and all 1-wire device state machines + * so they can respond to our requests. + * + * Return 0 - device(s) present, 1 - no devices present. + */ + if (w1_reset_bus(dev)) { + dev_info(&dev->dev, "No devices present on the wire.\n"); + break; + } + +#if 1 + w1_write_8(dev, W1_SEARCH); + for (i = 0; i < 64; ++i) { + /* + * Read 2 bits from bus. + * All who don't sleep must send ID bit and COMPLEMENT ID bit. + * They actually are ANDed between all senders. + */ + id_bit = w1_touch_bit(dev, 1); + comp_bit = w1_touch_bit(dev, 1); + + if (id_bit && comp_bit) + break; + + if (id_bit == 0 && comp_bit == 0) { + if (i == desc_bit) + search_bit = 1; + else if (i > desc_bit) + search_bit = 0; + else + search_bit = ((last >> i) & 0x1); + + if (search_bit == 0) { + last_zero = i; + if (last_zero < 9) + last_family_desc = last_zero; + } + + } + else + search_bit = id_bit; + + tmp = search_bit; + rn |= (tmp << i); + + /* + * Write 1 bit to bus + * and make all who don't have "search_bit" in "i"'th position + * in it's registration number sleep. + */ + if (dev->bus_master->touch_bit) + w1_touch_bit(dev, search_bit); + else + w1_write_bit(dev, search_bit); + + } +#endif + + if (desc_bit == last_zero) + last_device = 1; + + desc_bit = last_zero; + + w1_slave_found(dev->bus_master->data, rn); + } +} + +int w1_create_master_attributes(struct w1_master *dev) +{ + if ( device_create_file(&dev->dev, &w1_master_attribute_slaves) < 0 || + device_create_file(&dev->dev, &w1_master_attribute_slave_count) < 0 || + device_create_file(&dev->dev, &w1_master_attribute_attempts) < 0 || + device_create_file(&dev->dev, &w1_master_attribute_max_slave_count) < 0 || + device_create_file(&dev->dev, &w1_master_attribute_timeout) < 0|| + device_create_file(&dev->dev, &w1_master_attribute_pointer) < 0|| + device_create_file(&dev->dev, &w1_master_attribute_name) < 0) + return -EINVAL; + + return 0; +} + +void w1_destroy_master_attributes(struct w1_master *dev) +{ + device_remove_file(&dev->dev, &w1_master_attribute_slaves); + device_remove_file(&dev->dev, &w1_master_attribute_slave_count); + device_remove_file(&dev->dev, &w1_master_attribute_attempts); + device_remove_file(&dev->dev, &w1_master_attribute_max_slave_count); + device_remove_file(&dev->dev, &w1_master_attribute_timeout); + device_remove_file(&dev->dev, &w1_master_attribute_pointer); + device_remove_file(&dev->dev, &w1_master_attribute_name); +} + + +int w1_control(void *data) +{ + struct w1_slave *sl; + struct w1_master *dev; + struct list_head *ent, *ment, *n, *mn; + int err, have_to_wait = 0; + + daemonize("w1_control"); + allow_signal(SIGTERM); + + while (!control_needs_exit || have_to_wait) { + have_to_wait = 0; + + try_to_freeze(PF_FREEZE); + msleep_interruptible(w1_timeout * 1000); + + if (signal_pending(current)) + flush_signals(current); + + list_for_each_safe(ment, mn, &w1_masters) { + dev = list_entry(ment, struct w1_master, w1_master_entry); + + if (!control_needs_exit && !dev->need_exit) + continue; + /* + * Little race: we can create thread but not set the flag. + * Get a chance for external process to set flag up. + */ + if (!dev->initialized) { + have_to_wait = 1; + continue; + } + + spin_lock(&w1_mlock); + list_del(&dev->w1_master_entry); + spin_unlock(&w1_mlock); + + if (control_needs_exit) { + dev->need_exit = 1; + + err = kill_proc(dev->kpid, SIGTERM, 1); + if (err) + dev_err(&dev->dev, + "Failed to send signal to w1 kernel thread %d.\n", + dev->kpid); + } + + wait_for_completion(&dev->dev_exited); + + list_for_each_safe(ent, n, &dev->slist) { + sl = list_entry(ent, struct w1_slave, w1_slave_entry); + + if (!sl) + dev_warn(&dev->dev, + "%s: slave entry is NULL.\n", + __func__); + else { + list_del(&sl->w1_slave_entry); + + w1_slave_detach(sl); + kfree(sl); + } + } + w1_destroy_master_attributes(dev); + atomic_dec(&dev->refcnt); + } + } + + complete_and_exit(&w1_control_complete, 0); +} + +int w1_process(void *data) +{ + struct w1_master *dev = (struct w1_master *) data; + struct list_head *ent, *n; + struct w1_slave *sl; + + daemonize("%s", dev->name); + allow_signal(SIGTERM); + + while (!dev->need_exit) { + try_to_freeze(PF_FREEZE); + msleep_interruptible(w1_timeout * 1000); + + if (signal_pending(current)) + flush_signals(current); + + if (dev->need_exit) + break; + + if (!dev->initialized) + continue; + + if (down_interruptible(&dev->mutex)) + continue; + + list_for_each_safe(ent, n, &dev->slist) { + sl = list_entry(ent, struct w1_slave, w1_slave_entry); + + if (sl) + clear_bit(W1_SLAVE_ACTIVE, (long *)&sl->flags); + } + + w1_search_devices(dev, w1_slave_found); + + list_for_each_safe(ent, n, &dev->slist) { + sl = list_entry(ent, struct w1_slave, w1_slave_entry); + + if (sl && !test_bit(W1_SLAVE_ACTIVE, (unsigned long *)&sl->flags) && !--sl->ttl) { + list_del (&sl->w1_slave_entry); + + w1_slave_detach (sl); + kfree (sl); + + dev->slave_count--; + } + else if (test_bit(W1_SLAVE_ACTIVE, (unsigned long *)&sl->flags)) + sl->ttl = dev->slave_ttl; + } + up(&dev->mutex); + } + + atomic_dec(&dev->refcnt); + complete_and_exit(&dev->dev_exited, 0); + + return 0; +} + +int w1_init(void) +{ + int retval; + + printk(KERN_INFO "Driver for 1-wire Dallas network protocol.\n"); + + retval = bus_register(&w1_bus_type); + if (retval) { + printk(KERN_ERR "Failed to register bus. err=%d.\n", retval); + goto err_out_exit_init; + } + + retval = driver_register(&w1_driver); + if (retval) { + printk(KERN_ERR + "Failed to register master driver. err=%d.\n", + retval); + goto err_out_bus_unregister; + } + + control_thread = kernel_thread(&w1_control, NULL, 0); + if (control_thread < 0) { + printk(KERN_ERR "Failed to create control thread. err=%d\n", + control_thread); + retval = control_thread; + goto err_out_driver_unregister; + } + + return 0; + +err_out_driver_unregister: + driver_unregister(&w1_driver); + +err_out_bus_unregister: + bus_unregister(&w1_bus_type); + +err_out_exit_init: + return retval; +} + +void w1_fini(void) +{ + struct w1_master *dev; + struct list_head *ent, *n; + + list_for_each_safe(ent, n, &w1_masters) { + dev = list_entry(ent, struct w1_master, w1_master_entry); + __w1_remove_master_device(dev); + } + + control_needs_exit = 1; + + wait_for_completion(&w1_control_complete); + + driver_unregister(&w1_driver); + bus_unregister(&w1_bus_type); +} + +module_init(w1_init); +module_exit(w1_fini); 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