linux/drivers/power/test_power.c
Krzysztof Kozlowski 297d716f62 power_supply: Change ownership from driver to core
Change the ownership of power_supply structure from each driver
implementing the class to the power supply core.

The patch changes power_supply_register() function thus all drivers
implementing power supply class are adjusted.

Each driver provides the implementation of power supply. However it
should not be the owner of power supply class instance because it is
exposed by core to other subsystems with power_supply_get_by_name().
These other subsystems have no knowledge when the driver will unregister
the power supply. This leads to several issues when driver is unbound -
mostly because user of power supply accesses freed memory.

Instead let the core own the instance of struct 'power_supply'.  Other
users of this power supply will still access valid memory because it
will be freed when device reference count reaches 0. Currently this
means "it will leak" but power_supply_put() call in next patches will
solve it.

This solves invalid memory references in following race condition
scenario:

Thread 1: charger manager
Thread 2: power supply driver, used by charger manager

THREAD 1 (charger manager)         THREAD 2 (power supply driver)
==========================         ==============================
psy = power_supply_get_by_name()
                                   Driver unbind, .remove
                                     power_supply_unregister()
                                     Device fully removed
psy->get_property()

The 'get_property' call is executed in invalid context because the driver was
unbound and struct 'power_supply' memory was freed.

This could be observed easily with charger manager driver (here compiled
with max17040 fuel gauge):

$ cat /sys/devices/virtual/power_supply/cm-battery/capacity &
$ echo "1-0036" > /sys/bus/i2c/drivers/max17040/unbind
[   55.725123] Unable to handle kernel NULL pointer dereference at virtual address 00000000
[   55.732584] pgd = d98d4000
[   55.734060] [00000000] *pgd=5afa2831, *pte=00000000, *ppte=00000000
[   55.740318] Internal error: Oops: 80000007 [#1] PREEMPT SMP ARM
[   55.746210] Modules linked in:
[   55.749259] CPU: 1 PID: 2936 Comm: cat Tainted: G        W       3.19.0-rc1-next-20141226-00048-gf79f475f3c44-dirty #1496
[   55.760190] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree)
[   55.766270] task: d9b76f00 ti: daf54000 task.ti: daf54000
[   55.771647] PC is at 0x0
[   55.774182] LR is at charger_get_property+0x2f4/0x36c
[   55.779201] pc : [<00000000>]    lr : [<c034b0b4>]    psr: 60000013
[   55.779201] sp : daf55e90  ip : 00000003  fp : 00000000
[   55.790657] r10: 00000000  r9 : c06e2878  r8 : d9b26c68
[   55.795865] r7 : dad81610  r6 : daec7410  r5 : daf55ebc  r4 : 00000000
[   55.802367] r3 : 00000000  r2 : daf55ebc  r1 : 0000002a  r0 : d9b26c68
[   55.808879] Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment user
[   55.815994] Control: 10c5387d  Table: 598d406a  DAC: 00000015
[   55.821723] Process cat (pid: 2936, stack limit = 0xdaf54210)
[   55.827451] Stack: (0xdaf55e90 to 0xdaf56000)
[   55.831795] 5e80:                                     60000013 c01459c4 0000002a c06f8ef8
[   55.839956] 5ea0: db651000 c06f8ef8 daebac00 c04cb668 daebac08 c0346864 00000000 c01459c4
[   55.848115] 5ec0: d99eaa80 c06f8ef8 00000fff 00001000 db651000 c027f25c c027f240 d99eaa80
[   55.856274] 5ee0: d9a06c00 c0146218 daf55f18 00001000 d99eaa80 db4c18c0 00000001 00000001
[   55.864468] 5f00: daf55f80 c0144c78 c0144c54 c0107f90 00015000 d99eaab0 00000000 00000000
[   55.872603] 5f20: 000051c7 00000000 db4c18c0 c04a9370 00015000 00001000 daf55f80 00001000
[   55.880763] 5f40: daf54000 00015000 00000000 c00e53dc db4c18c0 c00e548c 0000000d 00008124
[   55.888937] 5f60: 00000001 00000000 00000000 db4c18c0 db4c18c0 00001000 00015000 c00e5550
[   55.897099] 5f80: 00000000 00000000 00001000 00001000 00015000 00000003 00000003 c000f364
[   55.905239] 5fa0: 00000000 c000f1a0 00001000 00015000 00000003 00015000 00001000 0001333c
[   55.913399] 5fc0: 00001000 00015000 00000003 00000003 00000002 00000000 00000000 00000000
[   55.921560] 5fe0: 7fffe000 be999850 0000a225 b6f3c19c 60000010 00000003 00000000 00000000
[   55.929744] [<c034b0b4>] (charger_get_property) from [<c0346864>] (power_supply_show_property+0x48/0x20c)
[   55.939286] [<c0346864>] (power_supply_show_property) from [<c027f25c>] (dev_attr_show+0x1c/0x48)
[   55.948130] [<c027f25c>] (dev_attr_show) from [<c0146218>] (sysfs_kf_seq_show+0x84/0x104)
[   55.956298] [<c0146218>] (sysfs_kf_seq_show) from [<c0144c78>] (kernfs_seq_show+0x24/0x28)
[   55.964536] [<c0144c78>] (kernfs_seq_show) from [<c0107f90>] (seq_read+0x1b0/0x484)
[   55.972172] [<c0107f90>] (seq_read) from [<c00e53dc>] (__vfs_read+0x18/0x4c)
[   55.979188] [<c00e53dc>] (__vfs_read) from [<c00e548c>] (vfs_read+0x7c/0x100)
[   55.986304] [<c00e548c>] (vfs_read) from [<c00e5550>] (SyS_read+0x40/0x8c)
[   55.993164] [<c00e5550>] (SyS_read) from [<c000f1a0>] (ret_fast_syscall+0x0/0x48)
[   56.000626] Code: bad PC value
[   56.011652] ---[ end trace 7b64343fbdae8ef1 ]---

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

[for the nvec part]
Reviewed-by: Marc Dietrich <marvin24@gmx.de>

[for compal-laptop.c]
Acked-by: Darren Hart <dvhart@linux.intel.com>

[for the mfd part]
Acked-by: Lee Jones <lee.jones@linaro.org>

[for the hid part]
Acked-by: Jiri Kosina <jkosina@suse.cz>

[for the acpi part]
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Signed-off-by: Sebastian Reichel <sre@kernel.org>
2015-03-13 23:15:51 +01:00

532 lines
14 KiB
C

/*
* Power supply driver for testing.
*
* Copyright 2010 Anton Vorontsov <cbouatmailru@gmail.com>
*
* Dynamic module parameter code from the Virtual Battery Driver
* Copyright (C) 2008 Pylone, Inc.
* By: Masashi YOKOTA <yokota@pylone.jp>
* Originally found here:
* http://downloads.pylone.jp/src/virtual_battery/virtual_battery-0.0.1.tar.bz2
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/power_supply.h>
#include <linux/errno.h>
#include <linux/delay.h>
#include <linux/vermagic.h>
enum test_power_id {
TEST_AC,
TEST_BATTERY,
TEST_USB,
TEST_POWER_NUM,
};
static int ac_online = 1;
static int usb_online = 1;
static int battery_status = POWER_SUPPLY_STATUS_DISCHARGING;
static int battery_health = POWER_SUPPLY_HEALTH_GOOD;
static int battery_present = 1; /* true */
static int battery_technology = POWER_SUPPLY_TECHNOLOGY_LION;
static int battery_capacity = 50;
static int battery_voltage = 3300;
static bool module_initialized;
static int test_power_get_ac_property(struct power_supply *psy,
enum power_supply_property psp,
union power_supply_propval *val)
{
switch (psp) {
case POWER_SUPPLY_PROP_ONLINE:
val->intval = ac_online;
break;
default:
return -EINVAL;
}
return 0;
}
static int test_power_get_usb_property(struct power_supply *psy,
enum power_supply_property psp,
union power_supply_propval *val)
{
switch (psp) {
case POWER_SUPPLY_PROP_ONLINE:
val->intval = usb_online;
break;
default:
return -EINVAL;
}
return 0;
}
static int test_power_get_battery_property(struct power_supply *psy,
enum power_supply_property psp,
union power_supply_propval *val)
{
switch (psp) {
case POWER_SUPPLY_PROP_MODEL_NAME:
val->strval = "Test battery";
break;
case POWER_SUPPLY_PROP_MANUFACTURER:
val->strval = "Linux";
break;
case POWER_SUPPLY_PROP_SERIAL_NUMBER:
val->strval = UTS_RELEASE;
break;
case POWER_SUPPLY_PROP_STATUS:
val->intval = battery_status;
break;
case POWER_SUPPLY_PROP_CHARGE_TYPE:
val->intval = POWER_SUPPLY_CHARGE_TYPE_FAST;
break;
case POWER_SUPPLY_PROP_HEALTH:
val->intval = battery_health;
break;
case POWER_SUPPLY_PROP_PRESENT:
val->intval = battery_present;
break;
case POWER_SUPPLY_PROP_TECHNOLOGY:
val->intval = battery_technology;
break;
case POWER_SUPPLY_PROP_CAPACITY_LEVEL:
val->intval = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
break;
case POWER_SUPPLY_PROP_CAPACITY:
case POWER_SUPPLY_PROP_CHARGE_NOW:
val->intval = battery_capacity;
break;
case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
case POWER_SUPPLY_PROP_CHARGE_FULL:
val->intval = 100;
break;
case POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG:
case POWER_SUPPLY_PROP_TIME_TO_FULL_NOW:
val->intval = 3600;
break;
case POWER_SUPPLY_PROP_TEMP:
val->intval = 26;
break;
case POWER_SUPPLY_PROP_VOLTAGE_NOW:
val->intval = battery_voltage;
break;
default:
pr_info("%s: some properties deliberately report errors.\n",
__func__);
return -EINVAL;
}
return 0;
}
static enum power_supply_property test_power_ac_props[] = {
POWER_SUPPLY_PROP_ONLINE,
};
static enum power_supply_property test_power_battery_props[] = {
POWER_SUPPLY_PROP_STATUS,
POWER_SUPPLY_PROP_CHARGE_TYPE,
POWER_SUPPLY_PROP_HEALTH,
POWER_SUPPLY_PROP_PRESENT,
POWER_SUPPLY_PROP_TECHNOLOGY,
POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
POWER_SUPPLY_PROP_CHARGE_FULL,
POWER_SUPPLY_PROP_CHARGE_NOW,
POWER_SUPPLY_PROP_CAPACITY,
POWER_SUPPLY_PROP_CAPACITY_LEVEL,
POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG,
POWER_SUPPLY_PROP_TIME_TO_FULL_NOW,
POWER_SUPPLY_PROP_MODEL_NAME,
POWER_SUPPLY_PROP_MANUFACTURER,
POWER_SUPPLY_PROP_SERIAL_NUMBER,
POWER_SUPPLY_PROP_TEMP,
POWER_SUPPLY_PROP_VOLTAGE_NOW,
};
static char *test_power_ac_supplied_to[] = {
"test_battery",
};
static struct power_supply *test_power_supplies[TEST_POWER_NUM];
static const struct power_supply_desc test_power_desc[] = {
[TEST_AC] = {
.name = "test_ac",
.type = POWER_SUPPLY_TYPE_MAINS,
.properties = test_power_ac_props,
.num_properties = ARRAY_SIZE(test_power_ac_props),
.get_property = test_power_get_ac_property,
},
[TEST_BATTERY] = {
.name = "test_battery",
.type = POWER_SUPPLY_TYPE_BATTERY,
.properties = test_power_battery_props,
.num_properties = ARRAY_SIZE(test_power_battery_props),
.get_property = test_power_get_battery_property,
},
[TEST_USB] = {
.name = "test_usb",
.type = POWER_SUPPLY_TYPE_USB,
.properties = test_power_ac_props,
.num_properties = ARRAY_SIZE(test_power_ac_props),
.get_property = test_power_get_usb_property,
},
};
static const struct power_supply_config test_power_configs[] = {
{
/* test_ac */
.supplied_to = test_power_ac_supplied_to,
.num_supplicants = ARRAY_SIZE(test_power_ac_supplied_to),
}, {
/* test_battery */
}, {
/* test_usb */
.supplied_to = test_power_ac_supplied_to,
.num_supplicants = ARRAY_SIZE(test_power_ac_supplied_to),
},
};
static int __init test_power_init(void)
{
int i;
int ret;
BUILD_BUG_ON(TEST_POWER_NUM != ARRAY_SIZE(test_power_supplies));
BUILD_BUG_ON(TEST_POWER_NUM != ARRAY_SIZE(test_power_configs));
for (i = 0; i < ARRAY_SIZE(test_power_supplies); i++) {
test_power_supplies[i] = power_supply_register(NULL,
&test_power_desc[i],
&test_power_configs[i]);
if (IS_ERR(test_power_supplies[i])) {
pr_err("%s: failed to register %s\n", __func__,
test_power_desc[i].name);
ret = PTR_ERR(test_power_supplies[i]);
goto failed;
}
}
module_initialized = true;
return 0;
failed:
while (--i >= 0)
power_supply_unregister(test_power_supplies[i]);
return ret;
}
module_init(test_power_init);
static void __exit test_power_exit(void)
{
int i;
/* Let's see how we handle changes... */
ac_online = 0;
usb_online = 0;
battery_status = POWER_SUPPLY_STATUS_DISCHARGING;
for (i = 0; i < ARRAY_SIZE(test_power_supplies); i++)
power_supply_changed(test_power_supplies[i]);
pr_info("%s: 'changed' event sent, sleeping for 10 seconds...\n",
__func__);
ssleep(10);
for (i = 0; i < ARRAY_SIZE(test_power_supplies); i++)
power_supply_unregister(test_power_supplies[i]);
module_initialized = false;
}
module_exit(test_power_exit);
#define MAX_KEYLENGTH 256
struct battery_property_map {
int value;
char const *key;
};
static struct battery_property_map map_ac_online[] = {
{ 0, "off" },
{ 1, "on" },
{ -1, NULL },
};
static struct battery_property_map map_status[] = {
{ POWER_SUPPLY_STATUS_CHARGING, "charging" },
{ POWER_SUPPLY_STATUS_DISCHARGING, "discharging" },
{ POWER_SUPPLY_STATUS_NOT_CHARGING, "not-charging" },
{ POWER_SUPPLY_STATUS_FULL, "full" },
{ -1, NULL },
};
static struct battery_property_map map_health[] = {
{ POWER_SUPPLY_HEALTH_GOOD, "good" },
{ POWER_SUPPLY_HEALTH_OVERHEAT, "overheat" },
{ POWER_SUPPLY_HEALTH_DEAD, "dead" },
{ POWER_SUPPLY_HEALTH_OVERVOLTAGE, "overvoltage" },
{ POWER_SUPPLY_HEALTH_UNSPEC_FAILURE, "failure" },
{ -1, NULL },
};
static struct battery_property_map map_present[] = {
{ 0, "false" },
{ 1, "true" },
{ -1, NULL },
};
static struct battery_property_map map_technology[] = {
{ POWER_SUPPLY_TECHNOLOGY_NiMH, "NiMH" },
{ POWER_SUPPLY_TECHNOLOGY_LION, "LION" },
{ POWER_SUPPLY_TECHNOLOGY_LIPO, "LIPO" },
{ POWER_SUPPLY_TECHNOLOGY_LiFe, "LiFe" },
{ POWER_SUPPLY_TECHNOLOGY_NiCd, "NiCd" },
{ POWER_SUPPLY_TECHNOLOGY_LiMn, "LiMn" },
{ -1, NULL },
};
static int map_get_value(struct battery_property_map *map, const char *key,
int def_val)
{
char buf[MAX_KEYLENGTH];
int cr;
strncpy(buf, key, MAX_KEYLENGTH);
buf[MAX_KEYLENGTH-1] = '\0';
cr = strnlen(buf, MAX_KEYLENGTH) - 1;
if (buf[cr] == '\n')
buf[cr] = '\0';
while (map->key) {
if (strncasecmp(map->key, buf, MAX_KEYLENGTH) == 0)
return map->value;
map++;
}
return def_val;
}
static const char *map_get_key(struct battery_property_map *map, int value,
const char *def_key)
{
while (map->key) {
if (map->value == value)
return map->key;
map++;
}
return def_key;
}
static inline void signal_power_supply_changed(struct power_supply *psy)
{
if (module_initialized)
power_supply_changed(psy);
}
static int param_set_ac_online(const char *key, const struct kernel_param *kp)
{
ac_online = map_get_value(map_ac_online, key, ac_online);
signal_power_supply_changed(test_power_supplies[TEST_AC]);
return 0;
}
static int param_get_ac_online(char *buffer, const struct kernel_param *kp)
{
strcpy(buffer, map_get_key(map_ac_online, ac_online, "unknown"));
return strlen(buffer);
}
static int param_set_usb_online(const char *key, const struct kernel_param *kp)
{
usb_online = map_get_value(map_ac_online, key, usb_online);
signal_power_supply_changed(test_power_supplies[TEST_USB]);
return 0;
}
static int param_get_usb_online(char *buffer, const struct kernel_param *kp)
{
strcpy(buffer, map_get_key(map_ac_online, usb_online, "unknown"));
return strlen(buffer);
}
static int param_set_battery_status(const char *key,
const struct kernel_param *kp)
{
battery_status = map_get_value(map_status, key, battery_status);
signal_power_supply_changed(test_power_supplies[TEST_BATTERY]);
return 0;
}
static int param_get_battery_status(char *buffer, const struct kernel_param *kp)
{
strcpy(buffer, map_get_key(map_status, battery_status, "unknown"));
return strlen(buffer);
}
static int param_set_battery_health(const char *key,
const struct kernel_param *kp)
{
battery_health = map_get_value(map_health, key, battery_health);
signal_power_supply_changed(test_power_supplies[TEST_BATTERY]);
return 0;
}
static int param_get_battery_health(char *buffer, const struct kernel_param *kp)
{
strcpy(buffer, map_get_key(map_health, battery_health, "unknown"));
return strlen(buffer);
}
static int param_set_battery_present(const char *key,
const struct kernel_param *kp)
{
battery_present = map_get_value(map_present, key, battery_present);
signal_power_supply_changed(test_power_supplies[TEST_AC]);
return 0;
}
static int param_get_battery_present(char *buffer,
const struct kernel_param *kp)
{
strcpy(buffer, map_get_key(map_present, battery_present, "unknown"));
return strlen(buffer);
}
static int param_set_battery_technology(const char *key,
const struct kernel_param *kp)
{
battery_technology = map_get_value(map_technology, key,
battery_technology);
signal_power_supply_changed(test_power_supplies[TEST_BATTERY]);
return 0;
}
static int param_get_battery_technology(char *buffer,
const struct kernel_param *kp)
{
strcpy(buffer,
map_get_key(map_technology, battery_technology, "unknown"));
return strlen(buffer);
}
static int param_set_battery_capacity(const char *key,
const struct kernel_param *kp)
{
int tmp;
if (1 != sscanf(key, "%d", &tmp))
return -EINVAL;
battery_capacity = tmp;
signal_power_supply_changed(test_power_supplies[TEST_BATTERY]);
return 0;
}
#define param_get_battery_capacity param_get_int
static int param_set_battery_voltage(const char *key,
const struct kernel_param *kp)
{
int tmp;
if (1 != sscanf(key, "%d", &tmp))
return -EINVAL;
battery_voltage = tmp;
signal_power_supply_changed(test_power_supplies[TEST_BATTERY]);
return 0;
}
#define param_get_battery_voltage param_get_int
static struct kernel_param_ops param_ops_ac_online = {
.set = param_set_ac_online,
.get = param_get_ac_online,
};
static struct kernel_param_ops param_ops_usb_online = {
.set = param_set_usb_online,
.get = param_get_usb_online,
};
static struct kernel_param_ops param_ops_battery_status = {
.set = param_set_battery_status,
.get = param_get_battery_status,
};
static struct kernel_param_ops param_ops_battery_present = {
.set = param_set_battery_present,
.get = param_get_battery_present,
};
static struct kernel_param_ops param_ops_battery_technology = {
.set = param_set_battery_technology,
.get = param_get_battery_technology,
};
static struct kernel_param_ops param_ops_battery_health = {
.set = param_set_battery_health,
.get = param_get_battery_health,
};
static struct kernel_param_ops param_ops_battery_capacity = {
.set = param_set_battery_capacity,
.get = param_get_battery_capacity,
};
static struct kernel_param_ops param_ops_battery_voltage = {
.set = param_set_battery_voltage,
.get = param_get_battery_voltage,
};
#define param_check_ac_online(name, p) __param_check(name, p, void);
#define param_check_usb_online(name, p) __param_check(name, p, void);
#define param_check_battery_status(name, p) __param_check(name, p, void);
#define param_check_battery_present(name, p) __param_check(name, p, void);
#define param_check_battery_technology(name, p) __param_check(name, p, void);
#define param_check_battery_health(name, p) __param_check(name, p, void);
#define param_check_battery_capacity(name, p) __param_check(name, p, void);
#define param_check_battery_voltage(name, p) __param_check(name, p, void);
module_param(ac_online, ac_online, 0644);
MODULE_PARM_DESC(ac_online, "AC charging state <on|off>");
module_param(usb_online, usb_online, 0644);
MODULE_PARM_DESC(usb_online, "USB charging state <on|off>");
module_param(battery_status, battery_status, 0644);
MODULE_PARM_DESC(battery_status,
"battery status <charging|discharging|not-charging|full>");
module_param(battery_present, battery_present, 0644);
MODULE_PARM_DESC(battery_present,
"battery presence state <good|overheat|dead|overvoltage|failure>");
module_param(battery_technology, battery_technology, 0644);
MODULE_PARM_DESC(battery_technology,
"battery technology <NiMH|LION|LIPO|LiFe|NiCd|LiMn>");
module_param(battery_health, battery_health, 0644);
MODULE_PARM_DESC(battery_health,
"battery health state <good|overheat|dead|overvoltage|failure>");
module_param(battery_capacity, battery_capacity, 0644);
MODULE_PARM_DESC(battery_capacity, "battery capacity (percentage)");
module_param(battery_voltage, battery_voltage, 0644);
MODULE_PARM_DESC(battery_voltage, "battery voltage (millivolts)");
MODULE_DESCRIPTION("Power supply driver for testing");
MODULE_AUTHOR("Anton Vorontsov <cbouatmailru@gmail.com>");
MODULE_LICENSE("GPL");