cregit-Linux how code gets into the kernel

Release 4.14 drivers/w1/w1.c

Directory: drivers/w1
/*
 * Copyright (c) 2004 Evgeniy Polyakov <zbr@ioremap.net>
 *
 * 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.
 */

#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/kthread.h>
#include <linux/freezer.h>
#include <linux/hwmon.h>

#include <linux/atomic.h>

#include "w1_internal.h"
#include "w1_netlink.h"


#define W1_FAMILY_DEFAULT	0


static int w1_timeout = 10;
module_param_named(timeout, w1_timeout, int, 0);
MODULE_PARM_DESC(timeout, "time in seconds between automatic slave searches");


static int w1_timeout_us = 0;
module_param_named(timeout_us, w1_timeout_us, int, 0);
MODULE_PARM_DESC(timeout_us,
		 "time in microseconds between automatic slave searches");

/* A search stops when w1_max_slave_count devices have been found in that
 * search.  The next search will start over and detect the same set of devices
 * on a static 1-wire bus.  Memory is not allocated based on this number, just
 * on the number of devices known to the kernel.  Having a high number does not
 * consume additional resources.  As a special case, if there is only one
 * device on the network and w1_max_slave_count is set to 1, the device id can
 * be read directly skipping the normal slower search process.
 */

int w1_max_slave_count = 64;
module_param_named(max_slave_count, w1_max_slave_count, int, 0);
MODULE_PARM_DESC(max_slave_count,
	"maximum number of slaves detected in a search");


int w1_max_slave_ttl = 10;
module_param_named(slave_ttl, w1_max_slave_ttl, int, 0);
MODULE_PARM_DESC(slave_ttl,
	"Number of searches not seeing a slave before it will be removed");


DEFINE_MUTEX(w1_mlock);

LIST_HEAD(w1_masters);


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

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

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Greg Kroah-Hartman15100.00%1100.00%
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static void w1_master_release(struct device *dev) { struct w1_master *md = dev_to_w1_master(dev); dev_dbg(dev, "%s: Releasing %s.\n", __func__, md->name); memset(md, 0, sizeof(struct w1_master) + sizeof(struct w1_bus_master)); kfree(md); }

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Evgeniy Polyakov3662.07%266.67%
Greg Kroah-Hartman2237.93%133.33%
Total58100.00%3100.00%


static void w1_slave_release(struct device *dev) { struct w1_slave *sl = dev_to_w1_slave(dev); dev_dbg(dev, "%s: Releasing %s [%p]\n", __func__, sl->name, sl); w1_family_put(sl->family); sl->master->slave_count--; }

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Evgeniy Polyakov2652.00%240.00%
Greg Kroah-Hartman2040.00%120.00%
David Fries48.00%240.00%
Total50100.00%5100.00%


static ssize_t name_show(struct device *dev, struct device_attribute *attr, char *buf) { struct w1_slave *sl = dev_to_w1_slave(dev); return sprintf(buf, "%s\n", sl->name); }

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Yani Ioannou511.90%125.00%
Total42100.00%4100.00%

static DEVICE_ATTR_RO(name);
static ssize_t id_show(struct device *dev, struct device_attribute *attr, char *buf) { struct w1_slave *sl = dev_to_w1_slave(dev); ssize_t count = sizeof(sl->reg_num); memcpy(buf, (u8 *)&sl->reg_num, count); return count; }

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Evgeniy Polyakov2338.98%120.00%
Greg Kroah-Hartman1830.51%240.00%
David Fries1525.42%120.00%
Rui Zhang35.08%120.00%
Total59100.00%5100.00%

static DEVICE_ATTR_RO(id); static struct attribute *w1_slave_attrs[] = { &dev_attr_name.attr, &dev_attr_id.attr, NULL, }; ATTRIBUTE_GROUPS(w1_slave); /* Default family */
static ssize_t rw_write(struct file *filp, struct kobject *kobj, struct bin_attribute *bin_attr, char *buf, loff_t off, size_t count) { struct w1_slave *sl = kobj_to_w1_slave(kobj); mutex_lock(&sl->master->mutex); if (w1_reset_select_slave(sl)) { count = 0; goto out_up; } w1_write_block(sl->master, buf, count); out_up: mutex_unlock(&sl->master->mutex); return count; }

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Evgeniy Polyakov8288.17%240.00%
Chris Wright55.38%120.00%
Rui Zhang55.38%120.00%
Greg Kroah-Hartman11.08%120.00%
Total93100.00%5100.00%


static ssize_t rw_read(struct file *filp, struct kobject *kobj, struct bin_attribute *bin_attr, char *buf, loff_t off, size_t count) { struct w1_slave *sl = kobj_to_w1_slave(kobj); mutex_lock(&sl->master->mutex); w1_read_block(sl->master, buf, count); mutex_unlock(&sl->master->mutex); return count; }

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Evgeniy Polyakov6485.33%240.00%
Chris Wright56.67%120.00%
Rui Zhang56.67%120.00%
Greg Kroah-Hartman11.33%120.00%
Total75100.00%5100.00%

static BIN_ATTR_RW(rw, PAGE_SIZE); static struct bin_attribute *w1_slave_bin_attrs[] = { &bin_attr_rw, NULL, }; static const struct attribute_group w1_slave_default_group = { .bin_attrs = w1_slave_bin_attrs, }; static const struct attribute_group *w1_slave_default_groups[] = { &w1_slave_default_group, NULL, }; static struct w1_family_ops w1_default_fops = { .groups = w1_slave_default_groups, }; static struct w1_family w1_default_family = { .fops = &w1_default_fops, }; static int w1_uevent(struct device *dev, struct kobj_uevent_env *env); static struct bus_type w1_bus_type = { .name = "w1", .match = w1_master_match, .uevent = w1_uevent, }; struct device_driver w1_master_driver = { .name = "w1_master_driver", .bus = &w1_bus_type, .probe = w1_master_probe, }; struct device w1_master_device = { .parent = NULL, .bus = &w1_bus_type, .init_name = "w1 bus master", .driver = &w1_master_driver, .release = &w1_master_release }; static struct device_driver w1_slave_driver = { .name = "w1_slave_driver", .bus = &w1_bus_type, }; #if 0 struct device w1_slave_device = { .parent = NULL, .bus = &w1_bus_type, .init_name = "w1 bus slave", .driver = &w1_slave_driver, .release = &w1_slave_release }; #endif /* 0 */
static ssize_t w1_master_attribute_show_name(struct device *dev, struct device_attribute *attr, char *buf) { struct w1_master *md = dev_to_w1_master(dev); ssize_t count; mutex_lock(&md->mutex); count = sprintf(buf, "%s\n", md->name); mutex_unlock(&md->mutex); return count; }

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Evgeniy Polyakov6092.31%480.00%
Yani Ioannou57.69%120.00%
Total65100.00%5100.00%


static ssize_t w1_master_attribute_store_search(struct device * dev, struct device_attribute *attr, const char * buf, size_t count) { long tmp; struct w1_master *md = dev_to_w1_master(dev); int ret; ret = kstrtol(buf, 0, &tmp); if (ret) return ret; mutex_lock(&md->mutex); md->search_count = tmp; mutex_unlock(&md->mutex); /* Only wake if it is going to be searching. */ if (tmp) wake_up_process(md->thread); return count; }

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Evgeniy Polyakov4546.88%350.00%
David Fries4041.67%233.33%
Jingoo Han1111.46%116.67%
Total96100.00%6100.00%


static ssize_t w1_master_attribute_show_search(struct device *dev, struct device_attribute *attr, char *buf) { struct w1_master *md = dev_to_w1_master(dev); ssize_t count; mutex_lock(&md->mutex); count = sprintf(buf, "%d\n", md->search_count); mutex_unlock(&md->mutex); return count; }

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David Fries6295.38%150.00%
Evgeniy Polyakov34.62%150.00%
Total65100.00%2100.00%


static ssize_t w1_master_attribute_store_pullup(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { long tmp; struct w1_master *md = dev_to_w1_master(dev); int ret; ret = kstrtol(buf, 0, &tmp); if (ret) return ret; mutex_lock(&md->mutex); md->enable_pullup = tmp; mutex_unlock(&md->mutex); return count; }

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David Fries5767.86%125.00%
Evgeniy Polyakov1619.05%250.00%
Jingoo Han1113.10%125.00%
Total84100.00%4100.00%


static ssize_t w1_master_attribute_show_pullup(struct device *dev, struct device_attribute *attr, char *buf) { struct w1_master *md = dev_to_w1_master(dev); ssize_t count; mutex_lock(&md->mutex); count = sprintf(buf, "%d\n", md->enable_pullup); mutex_unlock(&md->mutex); return count; }

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Evgeniy Polyakov6396.92%375.00%
David Fries23.08%125.00%
Total65100.00%4100.00%


static ssize_t w1_master_attribute_show_pointer(struct device *dev, struct device_attribute *attr, char *buf) { struct w1_master *md = dev_to_w1_master(dev); ssize_t count; mutex_lock(&md->mutex); count = sprintf(buf, "0x%p\n", md->bus_master); mutex_unlock(&md->mutex); return count; }

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Evgeniy Polyakov6092.31%480.00%
Yani Ioannou57.69%120.00%
Total65100.00%5100.00%


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

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Evgeniy Polyakov3286.49%266.67%
Yani Ioannou513.51%133.33%
Total37100.00%3100.00%


static ssize_t w1_master_attribute_show_timeout_us(struct device *dev, struct device_attribute *attr, char *buf) { ssize_t count; count = sprintf(buf, "%d\n", w1_timeout_us); return count; }

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Dmitry Khromov37100.00%1100.00%
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static ssize_t w1_master_attribute_store_max_slave_count(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { int tmp; struct w1_master *md = dev_to_w1_master(dev); if (kstrtoint(buf, 0, &tmp) || tmp < 1) return -EINVAL; mutex_lock(&md->mutex); md->max_slave_count = tmp; /* allow each time the max_slave_count is updated */ clear_bit(W1_WARN_MAX_COUNT, &md->flags); mutex_unlock(&md->mutex); return count; }

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David Fries9197.85%150.00%
Dan Carpenter22.15%150.00%
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static ssize_t w1_master_attribute_show_max_slave_count(struct device *dev, struct device_attribute *attr, char *buf) { struct w1_master *md = dev_to_w1_master(dev); ssize_t count; mutex_lock(&md->mutex); count = sprintf(buf, "%d\n", md->max_slave_count); mutex_unlock(&md->mutex); return count; }

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Evgeniy Polyakov6092.31%480.00%
Yani Ioannou57.69%120.00%
Total65100.00%5100.00%


static ssize_t w1_master_attribute_show_attempts(struct device *dev, struct device_attribute *attr, char *buf) { struct w1_master *md = dev_to_w1_master(dev); ssize_t count; mutex_lock(&md->mutex); count = sprintf(buf, "%lu\n", md->attempts); mutex_unlock(&md->mutex); return count; }

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Evgeniy Polyakov6092.31%480.00%
Yani Ioannou57.69%120.00%
Total65100.00%5100.00%


static ssize_t w1_master_attribute_show_slave_count(struct device *dev, struct device_attribute *attr, char *buf) { struct w1_master *md = dev_to_w1_master(dev); ssize_t count; mutex_lock(&md->mutex); count = sprintf(buf, "%d\n", md->slave_count); mutex_unlock(&md->mutex); return count; }

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Evgeniy Polyakov6092.31%480.00%
Yani Ioannou57.69%120.00%
Total65100.00%5100.00%


static ssize_t w1_master_attribute_show_slaves(struct device *dev, struct device_attribute *attr, char *buf) { struct w1_master *md = dev_to_w1_master(dev); int c = PAGE_SIZE; struct list_head *ent, *n; struct w1_slave *sl = NULL; mutex_lock(&md->list_mutex); 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); } if (!sl) c -= snprintf(buf + PAGE_SIZE - c, c, "not found.\n"); mutex_unlock(&md->list_mutex); return PAGE_SIZE - c; }

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Evgeniy Polyakov9672.73%466.67%
David Fries3123.48%116.67%
Yani Ioannou53.79%116.67%
Total132100.00%6100.00%


static ssize_t w1_master_attribute_show_add(struct device *dev, struct device_attribute *attr, char *buf) { int c = PAGE_SIZE; c -= snprintf(buf+PAGE_SIZE - c, c, "write device id xx-xxxxxxxxxxxx to add slave\n"); return PAGE_SIZE - c; }

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David Fries3680.00%133.33%
Evgeniy Polyakov920.00%266.67%
Total45100.00%3100.00%


static int w1_atoreg_num(struct device *dev, const char *buf, size_t count, struct w1_reg_num *rn) { unsigned int family; unsigned long long id; int i; u64 rn64_le; /* The CRC value isn't read from the user because the sysfs directory * doesn't include it and most messages from the bus search don't * print it either. It would be unreasonable for the user to then * provide it. */ const char *error_msg = "bad slave string format, expecting " "ff-dddddddddddd\n"; if (buf[2] != '-') { dev_err(dev, "%s", error_msg); return -EINVAL; } i = sscanf(buf, "%02x-%012llx", &family, &id); if (i != 2) { dev_err(dev, "%s", error_msg); return -EINVAL; } rn->family = family; rn->id = id; rn64_le = cpu_to_le64(*(u64 *)rn); rn->crc = w1_calc_crc8((u8 *)&rn64_le, 7); #if 0 dev_info(dev, "With CRC device is %02x.%012llx.%02x.\n", rn->family, (unsigned long long)rn->id, rn->crc); #endif return 0; }

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/* Searches the slaves in the w1_master and returns a pointer or NULL. * Note: must not hold list_mutex */
struct w1_slave *w1_slave_search_device(struct w1_master *dev, struct w1_reg_num *rn) { struct w1_slave *sl; mutex_lock(&dev->list_mutex); list_for_each_entry(sl, &dev->slist, w1_slave_entry) { if (sl->reg_num.family == rn->family && sl->reg_num.id == rn->id && sl->reg_num.crc == rn->crc) { mutex_unlock(&dev->list_mutex); return sl; } } mutex_unlock(&dev->list_mutex); return NULL; }

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David Fries9497.92%250.00%
Evgeniy Polyakov22.08%250.00%
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static ssize_t w1_master_attribute_store_add(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct w1_master *md = dev_to_w1_master(dev); struct w1_reg_num rn; struct w1_slave *sl; ssize_t result = count; if (w1_atoreg_num(dev, buf, count, &rn)) return -EINVAL; mutex_lock(&md->mutex); sl = w1_slave_search_device(md, &rn); /* It would be nice to do a targeted search one the one-wire bus * for the new device to see if it is out there or not. But the * current search doesn't support that. */ if (sl) { dev_info(dev, "Device %s already exists\n", sl->name); result = -EINVAL; } else { w1_attach_slave_device(md, &rn); } mutex_unlock(&md->mutex); return result; }

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static ssize_t w1_master_attribute_show_remove(struct device *dev, struct device_attribute *attr, char *buf) { int c = PAGE_SIZE; c -= snprintf(buf+PAGE_SIZE - c, c, "write device id xx-xxxxxxxxxxxx to remove slave\n"); return PAGE_SIZE - c; }

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static ssize_t w1_master_attribute_store_remove(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct w1_master *md = dev_to_w1_master(dev); struct w1_reg_num rn; struct w1_slave *sl; ssize_t result = count; if (w1_atoreg_num(dev, buf, count, &rn)) return -EINVAL; mutex_lock(&md->mutex); sl = w1_slave_search_device(md, &rn); if (sl) { result = w1_slave_detach(sl); /* refcnt 0 means it was detached in the call */ if (result == 0) result = count; } else { dev_info(dev, "Device %02x-%012llx doesn't exists\n", rn.family, (unsigned long long)rn.id); result = -EINVAL; } mutex_unlock(&md->mutex); return result; }

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#define W1_MASTER_ATTR_RO(_name, _mode) \ struct device_attribute w1_master_attribute_##_name = \ __ATTR(w1_master_##_name, _mode, \ w1_master_attribute_show_##_name, NULL) #define W1_MASTER_ATTR_RW(_name, _mode) \ struct device_attribute w1_master_attribute_##_name = \ __ATTR(w1_master_##_name, _mode, \ w1_master_attribute_show_##_name, \ w1_master_attribute_store_##_name) static W1_MASTER_ATTR_RO(name, S_IRUGO); static W1_MASTER_ATTR_RO(slaves, S_IRUGO); static W1_MASTER_ATTR_RO(slave_count, S_IRUGO); static W1_MASTER_ATTR_RW(max_slave_count, S_IRUGO | S_IWUSR | S_IWGRP); static W1_MASTER_ATTR_RO(attempts, S_IRUGO); static W1_MASTER_ATTR_RO(timeout, S_IRUGO); static W1_MASTER_ATTR_RO(timeout_us, S_IRUGO); static W1_MASTER_ATTR_RO(pointer, S_IRUGO); static W1_MASTER_ATTR_RW(search, S_IRUGO | S_IWUSR | S_IWGRP); static W1_MASTER_ATTR_RW(pullup, S_IRUGO | S_IWUSR | S_IWGRP); static W1_MASTER_ATTR_RW(add, S_IRUGO | S_IWUSR | S_IWGRP); static W1_MASTER_ATTR_RW(remove, S_IRUGO | S_IWUSR | S_IWGRP); static struct attribute *w1_master_default_attrs[] = { &w1_master_attribute_name.attr, &w1_master_attribute_slaves.attr, &w1_master_attribute_slave_count.attr, &w1_master_attribute_max_slave_count.attr, &w1_master_attribute_attempts.attr, &w1_master_attribute_timeout.attr, &w1_master_attribute_timeout_us.attr, &w1_master_attribute_pointer.attr, &w1_master_attribute_search.attr, &w1_master_attribute_pullup.attr, &w1_master_attribute_add.attr, &w1_master_attribute_remove.attr, NULL }; static const struct attribute_group w1_master_defattr_group = { .attrs = w1_master_default_attrs, };
int w1_create_master_attributes(struct w1_master *master) { return sysfs_create_group(&master->dev.kobj, &w1_master_defattr_group); }

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Evgeniy Polyakov1979.17%266.67%
Greg Kroah-Hartman520.83%133.33%
Total24100.00%3100.00%


void w1_destroy_master_attributes(struct w1_master *master) { sysfs_remove_group(&master->dev.kobj, &w1_master_defattr_group); }

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Evgeniy Polyakov1982.61%150.00%
Greg Kroah-Hartman417.39%150.00%
Total23100.00%2100.00%


static int w1_uevent(struct device *dev, struct kobj_uevent_env *env) { struct w1_master *md = NULL; struct w1_slave *sl = NULL; char *event_owner, *name; int err = 0; if (dev->driver == &w1_master_driver) { md = container_of(dev, struct w1_master, dev); event_owner = "master"; name = md->name; } else if (dev->driver == &w1_slave_driver) { sl = container_of(dev, struct w1_slave, dev); event_owner = "slave"; name = sl->name; } else { dev_dbg(dev, "Unknown event.\n"); return -EINVAL; } dev_dbg(dev, "Hotplug event for %s %s, bus_id=%s.\n", event_owner, name, dev_name(dev)); if (dev->driver != &w1_slave_driver || !sl) goto end; err = add_uevent_var(env, "W1_FID=%02X", sl->reg_num.family); if (err) goto end; err = add_uevent_var(env, "W1_SLAVE_ID=%024LX", (unsigned long long)sl->reg_num.id); end: return err; }

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Evgeniy Polyakov17687.56%228.57%
Kay Sievers125.97%342.86%
Devendra Naga104.98%114.29%
Andrew Morton31.49%114.29%
Total201100.00%7100.00%


static int w1_family_notify(unsigned long action, struct w1_slave *sl) { struct w1_family_ops *fops; int err; fops = sl->family->fops; if (!fops) return 0; switch (action) { case BUS_NOTIFY_ADD_DEVICE: /* if the family driver needs to initialize something... */ if (fops->add_slave) { err = fops->add_slave(sl); if (err < 0) { dev_err(&sl->dev, "add_slave() call failed. err=%d\n", err); return err; } } if (fops->groups) { err = sysfs_create_groups(&sl->