linux/drivers/power/supply/max14577_charger.c

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// SPDX-License-Identifier: GPL-2.0+
//
// max14577_charger.c - Battery charger driver for the Maxim 14577/77836
//
// Copyright (C) 2013,2014 Samsung Electronics
// Krzysztof Kozlowski <krzk@kernel.org>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/power_supply.h>
#include <linux/mfd/max14577-private.h>
#include <linux/mfd/max14577.h>
struct max14577_charger {
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>
2015-03-12 15:44:11 +08:00
struct device *dev;
struct max14577 *max14577;
struct power_supply *charger;
struct max14577_charger_platform_data *pdata;
};
/*
* Helper function for mapping values of STATUS2/CHGTYP register on max14577
* and max77836 chipsets to enum maxim_muic_charger_type.
*/
static enum max14577_muic_charger_type maxim_get_charger_type(
enum maxim_device_type dev_type, u8 val) {
switch (val) {
case MAX14577_CHARGER_TYPE_NONE:
case MAX14577_CHARGER_TYPE_USB:
case MAX14577_CHARGER_TYPE_DOWNSTREAM_PORT:
case MAX14577_CHARGER_TYPE_DEDICATED_CHG:
case MAX14577_CHARGER_TYPE_SPECIAL_500MA:
case MAX14577_CHARGER_TYPE_SPECIAL_1A:
return val;
case MAX14577_CHARGER_TYPE_DEAD_BATTERY:
case MAX14577_CHARGER_TYPE_RESERVED:
if (dev_type == MAXIM_DEVICE_TYPE_MAX77836)
val |= 0x8;
return val;
default:
WARN_ONCE(1, "max14577: Unsupported chgtyp register value 0x%02x", val);
return val;
}
}
static int max14577_get_charger_state(struct max14577_charger *chg, int *val)
{
struct regmap *rmap = chg->max14577->regmap;
int ret;
u8 reg_data;
/*
* Charging occurs only if:
* - CHGCTRL2/MBCHOSTEN == 1
* - STATUS2/CGMBC == 1
*
* TODO:
* - handle FULL after Top-off timer (EOC register may be off
* and the charger won't be charging although MBCHOSTEN is on)
* - handle properly dead-battery charging (respect timer)
* - handle timers (fast-charge and prequal) /MBCCHGERR/
*/
ret = max14577_read_reg(rmap, MAX14577_CHG_REG_CHG_CTRL2, &reg_data);
if (ret < 0)
goto out;
if ((reg_data & CHGCTRL2_MBCHOSTEN_MASK) == 0) {
*val = POWER_SUPPLY_STATUS_DISCHARGING;
goto out;
}
ret = max14577_read_reg(rmap, MAX14577_CHG_REG_STATUS3, &reg_data);
if (ret < 0)
goto out;
if (reg_data & STATUS3_CGMBC_MASK) {
/* Charger or USB-cable is connected */
if (reg_data & STATUS3_EOC_MASK)
*val = POWER_SUPPLY_STATUS_FULL;
else
*val = POWER_SUPPLY_STATUS_CHARGING;
goto out;
}
*val = POWER_SUPPLY_STATUS_DISCHARGING;
out:
return ret;
}
/*
* Supported charge types:
* - POWER_SUPPLY_CHARGE_TYPE_NONE
* - POWER_SUPPLY_CHARGE_TYPE_FAST
*/
static int max14577_get_charge_type(struct max14577_charger *chg, int *val)
{
int ret, charging;
/*
* TODO: CHARGE_TYPE_TRICKLE (VCHGR_RC or EOC)?
* As spec says:
* [after reaching EOC interrupt]
* "When the battery is fully charged, the 30-minute (typ)
* top-off timer starts. The device continues to trickle
* charge the battery until the top-off timer runs out."
*/
ret = max14577_get_charger_state(chg, &charging);
if (ret < 0)
return ret;
if (charging == POWER_SUPPLY_STATUS_CHARGING)
*val = POWER_SUPPLY_CHARGE_TYPE_FAST;
else
*val = POWER_SUPPLY_CHARGE_TYPE_NONE;
return 0;
}
static int max14577_get_online(struct max14577_charger *chg, int *val)
{
struct regmap *rmap = chg->max14577->regmap;
u8 reg_data;
int ret;
enum max14577_muic_charger_type chg_type;
ret = max14577_read_reg(rmap, MAX14577_MUIC_REG_STATUS2, &reg_data);
if (ret < 0)
return ret;
reg_data = ((reg_data & STATUS2_CHGTYP_MASK) >> STATUS2_CHGTYP_SHIFT);
chg_type = maxim_get_charger_type(chg->max14577->dev_type, reg_data);
switch (chg_type) {
case MAX14577_CHARGER_TYPE_USB:
case MAX14577_CHARGER_TYPE_DEDICATED_CHG:
case MAX14577_CHARGER_TYPE_SPECIAL_500MA:
case MAX14577_CHARGER_TYPE_SPECIAL_1A:
case MAX14577_CHARGER_TYPE_DEAD_BATTERY:
case MAX77836_CHARGER_TYPE_SPECIAL_BIAS:
*val = 1;
break;
case MAX14577_CHARGER_TYPE_NONE:
case MAX14577_CHARGER_TYPE_DOWNSTREAM_PORT:
case MAX14577_CHARGER_TYPE_RESERVED:
case MAX77836_CHARGER_TYPE_RESERVED:
default:
*val = 0;
}
return 0;
}
/*
* Supported health statuses:
* - POWER_SUPPLY_HEALTH_DEAD
* - POWER_SUPPLY_HEALTH_OVERVOLTAGE
* - POWER_SUPPLY_HEALTH_GOOD
*/
static int max14577_get_battery_health(struct max14577_charger *chg, int *val)
{
struct regmap *rmap = chg->max14577->regmap;
int ret;
u8 reg_data;
enum max14577_muic_charger_type chg_type;
ret = max14577_read_reg(rmap, MAX14577_MUIC_REG_STATUS2, &reg_data);
if (ret < 0)
goto out;
reg_data = ((reg_data & STATUS2_CHGTYP_MASK) >> STATUS2_CHGTYP_SHIFT);
chg_type = maxim_get_charger_type(chg->max14577->dev_type, reg_data);
if (chg_type == MAX14577_CHARGER_TYPE_DEAD_BATTERY) {
*val = POWER_SUPPLY_HEALTH_DEAD;
goto out;
}
ret = max14577_read_reg(rmap, MAX14577_CHG_REG_STATUS3, &reg_data);
if (ret < 0)
goto out;
if (reg_data & STATUS3_OVP_MASK) {
*val = POWER_SUPPLY_HEALTH_OVERVOLTAGE;
goto out;
}
/* Not dead, not overvoltage */
*val = POWER_SUPPLY_HEALTH_GOOD;
out:
return ret;
}
/*
* Always returns 1.
* The max14577 chip doesn't report any status of battery presence.
* Lets assume that it will always be used with some battery.
*/
static int max14577_get_present(struct max14577_charger *chg, int *val)
{
*val = 1;
return 0;
}
static int max14577_set_fast_charge_timer(struct max14577_charger *chg,
unsigned long hours)
{
u8 reg_data;
switch (hours) {
case 5 ... 7:
reg_data = hours - 3;
break;
case 0:
/* Disable */
reg_data = 0x7;
break;
default:
dev_err(chg->dev, "Wrong value for Fast-Charge Timer: %lu\n",
hours);
return -EINVAL;
}
reg_data <<= CHGCTRL1_TCHW_SHIFT;
return max14577_update_reg(chg->max14577->regmap,
MAX14577_REG_CHGCTRL1, CHGCTRL1_TCHW_MASK, reg_data);
}
static int max14577_init_constant_voltage(struct max14577_charger *chg,
unsigned int uvolt)
{
u8 reg_data;
if (uvolt < MAXIM_CHARGER_CONSTANT_VOLTAGE_MIN ||
uvolt > MAXIM_CHARGER_CONSTANT_VOLTAGE_MAX)
return -EINVAL;
if (uvolt == 4200000)
reg_data = 0x0;
else if (uvolt == MAXIM_CHARGER_CONSTANT_VOLTAGE_MAX)
reg_data = 0x1f;
else if (uvolt <= 4280000) {
unsigned int val = uvolt;
val -= MAXIM_CHARGER_CONSTANT_VOLTAGE_MIN;
val /= MAXIM_CHARGER_CONSTANT_VOLTAGE_STEP;
if (uvolt <= 4180000)
reg_data = 0x1 + val;
else
reg_data = val; /* Fix for gap between 4.18V and 4.22V */
} else
return -EINVAL;
reg_data <<= CHGCTRL3_MBCCVWRC_SHIFT;
return max14577_write_reg(chg->max14577->regmap,
MAX14577_CHG_REG_CHG_CTRL3, reg_data);
}
static int max14577_init_eoc(struct max14577_charger *chg,
unsigned int uamp)
{
unsigned int current_bits = 0xf;
u8 reg_data;
switch (chg->max14577->dev_type) {
case MAXIM_DEVICE_TYPE_MAX77836:
if (uamp < 5000)
return -EINVAL; /* Requested current is too low */
if (uamp >= 7500 && uamp < 10000)
current_bits = 0x0;
else if (uamp <= 50000) {
/* <5000, 7499> and <10000, 50000> */
current_bits = uamp / 5000;
} else {
uamp = min(uamp, 100000U) - 50000U;
current_bits = 0xa + uamp / 10000;
}
break;
case MAXIM_DEVICE_TYPE_MAX14577:
default:
if (uamp < MAX14577_CHARGER_EOC_CURRENT_LIMIT_MIN)
return -EINVAL; /* Requested current is too low */
uamp = min(uamp, MAX14577_CHARGER_EOC_CURRENT_LIMIT_MAX);
uamp -= MAX14577_CHARGER_EOC_CURRENT_LIMIT_MIN;
current_bits = uamp / MAX14577_CHARGER_EOC_CURRENT_LIMIT_STEP;
break;
}
reg_data = current_bits << CHGCTRL5_EOCS_SHIFT;
return max14577_update_reg(chg->max14577->regmap,
MAX14577_CHG_REG_CHG_CTRL5, CHGCTRL5_EOCS_MASK,
reg_data);
}
static int max14577_init_fast_charge(struct max14577_charger *chg,
unsigned int uamp)
{
u8 reg_data;
int ret;
const struct maxim_charger_current *limits =
&maxim_charger_currents[chg->max14577->dev_type];
ret = maxim_charger_calc_reg_current(limits, uamp, uamp, &reg_data);
if (ret) {
dev_err(chg->dev, "Wrong value for fast charge: %u\n", uamp);
return ret;
}
return max14577_update_reg(chg->max14577->regmap,
MAX14577_CHG_REG_CHG_CTRL4,
CHGCTRL4_MBCICHWRCL_MASK | CHGCTRL4_MBCICHWRCH_MASK,
reg_data);
}
/*
* Sets charger registers to proper and safe default values.
* Some of these values are equal to defaults in MAX14577E
* data sheet but there are minor differences.
*/
static int max14577_charger_reg_init(struct max14577_charger *chg)
{
struct regmap *rmap = chg->max14577->regmap;
u8 reg_data;
int ret;
/*
* Charger-Type Manual Detection, default off (set CHGTYPMAN to 0)
* Charger-Detection Enable, default on (set CHGDETEN to 1)
* Combined mask of CHGDETEN and CHGTYPMAN will zero the CHGTYPMAN bit
*/
reg_data = 0x1 << CDETCTRL1_CHGDETEN_SHIFT;
max14577_update_reg(rmap, MAX14577_REG_CDETCTRL1,
CDETCTRL1_CHGDETEN_MASK | CDETCTRL1_CHGTYPMAN_MASK,
reg_data);
/*
* Wall-Adapter Rapid Charge, default on
* Battery-Charger, default on
*/
reg_data = 0x1 << CHGCTRL2_VCHGR_RC_SHIFT;
reg_data |= 0x1 << CHGCTRL2_MBCHOSTEN_SHIFT;
max14577_write_reg(rmap, MAX14577_REG_CHGCTRL2, reg_data);
/* Auto Charging Stop, default off */
reg_data = 0x0 << CHGCTRL6_AUTOSTOP_SHIFT;
max14577_write_reg(rmap, MAX14577_REG_CHGCTRL6, reg_data);
ret = max14577_init_constant_voltage(chg, chg->pdata->constant_uvolt);
if (ret)
return ret;
ret = max14577_init_eoc(chg, chg->pdata->eoc_uamp);
if (ret)
return ret;
ret = max14577_init_fast_charge(chg, chg->pdata->fast_charge_uamp);
if (ret)
return ret;
ret = max14577_set_fast_charge_timer(chg,
MAXIM_CHARGER_FAST_CHARGE_TIMER_DEFAULT);
if (ret)
return ret;
/* Initialize Overvoltage-Protection Threshold */
switch (chg->pdata->ovp_uvolt) {
case 7500000:
reg_data = 0x0;
break;
case 6000000:
case 6500000:
case 7000000:
reg_data = 0x1 + (chg->pdata->ovp_uvolt - 6000000) / 500000;
break;
default:
dev_err(chg->dev, "Wrong value for OVP: %u\n",
chg->pdata->ovp_uvolt);
return -EINVAL;
}
reg_data <<= CHGCTRL7_OTPCGHCVS_SHIFT;
max14577_write_reg(rmap, MAX14577_REG_CHGCTRL7, reg_data);
return 0;
}
/* Support property from charger */
static enum power_supply_property max14577_charger_props[] = {
POWER_SUPPLY_PROP_STATUS,
POWER_SUPPLY_PROP_CHARGE_TYPE,
POWER_SUPPLY_PROP_HEALTH,
POWER_SUPPLY_PROP_PRESENT,
POWER_SUPPLY_PROP_ONLINE,
POWER_SUPPLY_PROP_MODEL_NAME,
POWER_SUPPLY_PROP_MANUFACTURER,
};
static const char * const model_names[] = {
[MAXIM_DEVICE_TYPE_UNKNOWN] = "MAX14577-like",
[MAXIM_DEVICE_TYPE_MAX14577] = "MAX14577",
[MAXIM_DEVICE_TYPE_MAX77836] = "MAX77836",
};
static const char *manufacturer = "Maxim Integrated";
static int max14577_charger_get_property(struct power_supply *psy,
enum power_supply_property psp,
union power_supply_propval *val)
{
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>
2015-03-12 15:44:11 +08:00
struct max14577_charger *chg = power_supply_get_drvdata(psy);
int ret = 0;
switch (psp) {
case POWER_SUPPLY_PROP_STATUS:
ret = max14577_get_charger_state(chg, &val->intval);
break;
case POWER_SUPPLY_PROP_CHARGE_TYPE:
ret = max14577_get_charge_type(chg, &val->intval);
break;
case POWER_SUPPLY_PROP_HEALTH:
ret = max14577_get_battery_health(chg, &val->intval);
break;
case POWER_SUPPLY_PROP_PRESENT:
ret = max14577_get_present(chg, &val->intval);
break;
case POWER_SUPPLY_PROP_ONLINE:
ret = max14577_get_online(chg, &val->intval);
break;
case POWER_SUPPLY_PROP_MODEL_NAME:
BUILD_BUG_ON(ARRAY_SIZE(model_names) != MAXIM_DEVICE_TYPE_NUM);
val->strval = model_names[chg->max14577->dev_type];
break;
case POWER_SUPPLY_PROP_MANUFACTURER:
val->strval = manufacturer;
break;
default:
return -EINVAL;
}
return ret;
}
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>
2015-03-12 15:44:11 +08:00
static const struct power_supply_desc max14577_charger_desc = {
.name = "max14577-charger",
.type = POWER_SUPPLY_TYPE_BATTERY,
.properties = max14577_charger_props,
.num_properties = ARRAY_SIZE(max14577_charger_props),
.get_property = max14577_charger_get_property,
};
#ifdef CONFIG_OF
static struct max14577_charger_platform_data *max14577_charger_dt_init(
struct platform_device *pdev)
{
struct max14577_charger_platform_data *pdata;
struct device_node *np = pdev->dev.of_node;
int ret;
if (!np) {
dev_err(&pdev->dev, "No charger OF node\n");
return ERR_PTR(-EINVAL);
}
pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
if (!pdata)
return ERR_PTR(-ENOMEM);
ret = of_property_read_u32(np, "maxim,constant-uvolt",
&pdata->constant_uvolt);
if (ret) {
dev_err(&pdev->dev, "Cannot parse maxim,constant-uvolt field from DT\n");
return ERR_PTR(ret);
}
ret = of_property_read_u32(np, "maxim,fast-charge-uamp",
&pdata->fast_charge_uamp);
if (ret) {
dev_err(&pdev->dev, "Cannot parse maxim,fast-charge-uamp field from DT\n");
return ERR_PTR(ret);
}
ret = of_property_read_u32(np, "maxim,eoc-uamp", &pdata->eoc_uamp);
if (ret) {
dev_err(&pdev->dev, "Cannot parse maxim,eoc-uamp field from DT\n");
return ERR_PTR(ret);
}
ret = of_property_read_u32(np, "maxim,ovp-uvolt", &pdata->ovp_uvolt);
if (ret) {
dev_err(&pdev->dev, "Cannot parse maxim,ovp-uvolt field from DT\n");
return ERR_PTR(ret);
}
return pdata;
}
#else /* CONFIG_OF */
static struct max14577_charger_platform_data *max14577_charger_dt_init(
struct platform_device *pdev)
{
return NULL;
}
#endif /* CONFIG_OF */
static ssize_t show_fast_charge_timer(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct max14577_charger *chg = dev_get_drvdata(dev);
u8 reg_data;
int ret;
unsigned int val;
ret = max14577_read_reg(chg->max14577->regmap, MAX14577_REG_CHGCTRL1,
&reg_data);
if (ret)
return ret;
reg_data &= CHGCTRL1_TCHW_MASK;
reg_data >>= CHGCTRL1_TCHW_SHIFT;
switch (reg_data) {
case 0x2 ... 0x4:
val = reg_data + 3;
break;
case 0x7:
val = 0;
break;
default:
val = 5;
break;
}
return scnprintf(buf, PAGE_SIZE, "%u\n", val);
}
static ssize_t store_fast_charge_timer(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
struct max14577_charger *chg = dev_get_drvdata(dev);
unsigned long val;
int ret;
ret = kstrtoul(buf, 10, &val);
if (ret)
return ret;
ret = max14577_set_fast_charge_timer(chg, val);
if (ret)
return ret;
return count;
}
static DEVICE_ATTR(fast_charge_timer, S_IRUGO | S_IWUSR,
show_fast_charge_timer, store_fast_charge_timer);
static int max14577_charger_probe(struct platform_device *pdev)
{
struct max14577_charger *chg;
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>
2015-03-12 15:44:11 +08:00
struct power_supply_config psy_cfg = {};
struct max14577 *max14577 = dev_get_drvdata(pdev->dev.parent);
int ret;
chg = devm_kzalloc(&pdev->dev, sizeof(*chg), GFP_KERNEL);
if (!chg)
return -ENOMEM;
platform_set_drvdata(pdev, chg);
chg->dev = &pdev->dev;
chg->max14577 = max14577;
chg->pdata = max14577_charger_dt_init(pdev);
if (IS_ERR_OR_NULL(chg->pdata))
return PTR_ERR(chg->pdata);
ret = max14577_charger_reg_init(chg);
if (ret)
return ret;
ret = device_create_file(&pdev->dev, &dev_attr_fast_charge_timer);
if (ret) {
dev_err(&pdev->dev, "failed: create sysfs entry\n");
return ret;
}
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>
2015-03-12 15:44:11 +08:00
psy_cfg.drv_data = chg;
chg->charger = power_supply_register(&pdev->dev, &max14577_charger_desc,
&psy_cfg);
if (IS_ERR(chg->charger)) {
dev_err(&pdev->dev, "failed: power supply register\n");
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>
2015-03-12 15:44:11 +08:00
ret = PTR_ERR(chg->charger);
goto err;
}
/* Check for valid values for charger */
BUILD_BUG_ON(MAX14577_CHARGER_EOC_CURRENT_LIMIT_MIN +
MAX14577_CHARGER_EOC_CURRENT_LIMIT_STEP * 0xf !=
MAX14577_CHARGER_EOC_CURRENT_LIMIT_MAX);
return 0;
err:
device_remove_file(&pdev->dev, &dev_attr_fast_charge_timer);
return ret;
}
static int max14577_charger_remove(struct platform_device *pdev)
{
struct max14577_charger *chg = platform_get_drvdata(pdev);
device_remove_file(&pdev->dev, &dev_attr_fast_charge_timer);
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>
2015-03-12 15:44:11 +08:00
power_supply_unregister(chg->charger);
return 0;
}
static const struct platform_device_id max14577_charger_id[] = {
{ "max14577-charger", MAXIM_DEVICE_TYPE_MAX14577, },
{ "max77836-charger", MAXIM_DEVICE_TYPE_MAX77836, },
{ }
};
MODULE_DEVICE_TABLE(platform, max14577_charger_id);
static const struct of_device_id of_max14577_charger_dt_match[] = {
{ .compatible = "maxim,max14577-charger",
.data = (void *)MAXIM_DEVICE_TYPE_MAX14577, },
{ .compatible = "maxim,max77836-charger",
.data = (void *)MAXIM_DEVICE_TYPE_MAX77836, },
{ },
};
MODULE_DEVICE_TABLE(of, of_max14577_charger_dt_match);
static struct platform_driver max14577_charger_driver = {
.driver = {
.name = "max14577-charger",
.of_match_table = of_max14577_charger_dt_match,
},
.probe = max14577_charger_probe,
.remove = max14577_charger_remove,
.id_table = max14577_charger_id,
};
module_platform_driver(max14577_charger_driver);
MODULE_AUTHOR("Krzysztof Kozlowski <krzk@kernel.org>");
MODULE_DESCRIPTION("Maxim 14577/77836 charger driver");
MODULE_LICENSE("GPL");