![Krzysztof Kozlowski](/assets/img/avatar_default.png)
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>
553 lines
14 KiB
C
553 lines
14 KiB
C
/*
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* I2C client/driver for the Linear Technology LTC2941 and LTC2943
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* Battery Gas Gauge IC
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*
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* Copyright (C) 2014 Topic Embedded Systems
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*
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* Author: Auryn Verwegen
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* Author: Mike Looijmans
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*/
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/types.h>
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#include <linux/errno.h>
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#include <linux/swab.h>
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#include <linux/i2c.h>
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#include <linux/delay.h>
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#include <linux/idr.h>
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#include <linux/power_supply.h>
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#include <linux/slab.h>
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#define I16_MSB(x) ((x >> 8) & 0xFF)
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#define I16_LSB(x) (x & 0xFF)
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#define LTC294X_WORK_DELAY 10 /* Update delay in seconds */
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#define LTC294X_MAX_VALUE 0xFFFF
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#define LTC294X_MID_SUPPLY 0x7FFF
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#define LTC2941_MAX_PRESCALER_EXP 7
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#define LTC2943_MAX_PRESCALER_EXP 6
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enum ltc294x_reg {
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LTC294X_REG_STATUS = 0x00,
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LTC294X_REG_CONTROL = 0x01,
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LTC294X_REG_ACC_CHARGE_MSB = 0x02,
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LTC294X_REG_ACC_CHARGE_LSB = 0x03,
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LTC294X_REG_THRESH_HIGH_MSB = 0x04,
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LTC294X_REG_THRESH_HIGH_LSB = 0x05,
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LTC294X_REG_THRESH_LOW_MSB = 0x06,
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LTC294X_REG_THRESH_LOW_LSB = 0x07,
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LTC294X_REG_VOLTAGE_MSB = 0x08,
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LTC294X_REG_VOLTAGE_LSB = 0x09,
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LTC294X_REG_CURRENT_MSB = 0x0E,
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LTC294X_REG_CURRENT_LSB = 0x0F,
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LTC294X_REG_TEMPERATURE_MSB = 0x14,
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LTC294X_REG_TEMPERATURE_LSB = 0x15,
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};
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#define LTC2943_REG_CONTROL_MODE_MASK (BIT(7) | BIT(6))
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#define LTC2943_REG_CONTROL_MODE_SCAN BIT(7)
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#define LTC294X_REG_CONTROL_PRESCALER_MASK (BIT(5) | BIT(4) | BIT(3))
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#define LTC294X_REG_CONTROL_SHUTDOWN_MASK (BIT(0))
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#define LTC294X_REG_CONTROL_PRESCALER_SET(x) \
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((x << 3) & LTC294X_REG_CONTROL_PRESCALER_MASK)
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#define LTC294X_REG_CONTROL_ALCC_CONFIG_DISABLED 0
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#define LTC2941_NUM_REGS 0x08
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#define LTC2943_NUM_REGS 0x18
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struct ltc294x_info {
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struct i2c_client *client; /* I2C Client pointer */
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struct power_supply *supply; /* Supply pointer */
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struct power_supply_desc supply_desc; /* Supply description */
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struct delayed_work work; /* Work scheduler */
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int num_regs; /* Number of registers (chip type) */
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int id; /* Identifier of ltc294x chip */
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int charge; /* Last charge register content */
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int r_sense; /* mOhm */
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int Qlsb; /* nAh */
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};
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static DEFINE_IDR(ltc294x_id);
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static DEFINE_MUTEX(ltc294x_lock);
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static inline int convert_bin_to_uAh(
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const struct ltc294x_info *info, int Q)
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{
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return ((Q * (info->Qlsb / 10))) / 100;
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}
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static inline int convert_uAh_to_bin(
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const struct ltc294x_info *info, int uAh)
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{
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int Q;
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Q = (uAh * 100) / (info->Qlsb/10);
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return (Q < LTC294X_MAX_VALUE) ? Q : LTC294X_MAX_VALUE;
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}
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static int ltc294x_read_regs(struct i2c_client *client,
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enum ltc294x_reg reg, u8 *buf, int num_regs)
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{
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int ret;
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struct i2c_msg msgs[2] = { };
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u8 reg_start = reg;
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msgs[0].addr = client->addr;
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msgs[0].len = 1;
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msgs[0].buf = ®_start;
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msgs[1].addr = client->addr;
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msgs[1].len = num_regs;
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msgs[1].buf = buf;
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msgs[1].flags = I2C_M_RD;
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ret = i2c_transfer(client->adapter, &msgs[0], 2);
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if (ret < 0) {
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dev_err(&client->dev, "ltc2941 read_reg failed!\n");
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return ret;
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}
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dev_dbg(&client->dev, "%s (%#x, %d) -> %#x\n",
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__func__, reg, num_regs, *buf);
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return 0;
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}
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static int ltc294x_write_regs(struct i2c_client *client,
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enum ltc294x_reg reg, const u8 *buf, int num_regs)
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{
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int ret;
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u8 reg_start = reg;
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ret = i2c_smbus_write_i2c_block_data(client, reg_start, num_regs, buf);
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if (ret < 0) {
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dev_err(&client->dev, "ltc2941 write_reg failed!\n");
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return ret;
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}
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dev_dbg(&client->dev, "%s (%#x, %d) -> %#x\n",
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__func__, reg, num_regs, *buf);
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return 0;
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}
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static int ltc294x_reset(const struct ltc294x_info *info, int prescaler_exp)
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{
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int ret;
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u8 value;
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u8 control;
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/* Read status and control registers */
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ret = ltc294x_read_regs(info->client, LTC294X_REG_CONTROL, &value, 1);
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if (ret < 0) {
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dev_err(&info->client->dev,
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"Could not read registers from device\n");
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goto error_exit;
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}
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control = LTC294X_REG_CONTROL_PRESCALER_SET(prescaler_exp) |
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LTC294X_REG_CONTROL_ALCC_CONFIG_DISABLED;
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/* Put the 2943 into "monitor" mode, so it measures every 10 sec */
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if (info->num_regs == LTC2943_NUM_REGS)
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control |= LTC2943_REG_CONTROL_MODE_SCAN;
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if (value != control) {
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ret = ltc294x_write_regs(info->client,
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LTC294X_REG_CONTROL, &control, 1);
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if (ret < 0) {
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dev_err(&info->client->dev,
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"Could not write register\n");
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goto error_exit;
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}
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}
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return 0;
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error_exit:
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return ret;
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}
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static int ltc294x_read_charge_register(const struct ltc294x_info *info)
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{
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int ret;
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u8 datar[2];
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ret = ltc294x_read_regs(info->client,
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LTC294X_REG_ACC_CHARGE_MSB, &datar[0], 2);
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if (ret < 0)
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return ret;
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return (datar[0] << 8) + datar[1];
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}
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static int ltc294x_get_charge_now(const struct ltc294x_info *info, int *val)
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{
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int value = ltc294x_read_charge_register(info);
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if (value < 0)
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return value;
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/* When r_sense < 0, this counts up when the battery discharges */
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if (info->Qlsb < 0)
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value -= 0xFFFF;
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*val = convert_bin_to_uAh(info, value);
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return 0;
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}
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static int ltc294x_set_charge_now(const struct ltc294x_info *info, int val)
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{
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int ret;
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u8 dataw[2];
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u8 ctrl_reg;
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s32 value;
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value = convert_uAh_to_bin(info, val);
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/* Direction depends on how sense+/- were connected */
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if (info->Qlsb < 0)
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value += 0xFFFF;
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if ((value < 0) || (value > 0xFFFF)) /* input validation */
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return -EINVAL;
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/* Read control register */
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ret = ltc294x_read_regs(info->client,
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LTC294X_REG_CONTROL, &ctrl_reg, 1);
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if (ret < 0)
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return ret;
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/* Disable analog section */
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ctrl_reg |= LTC294X_REG_CONTROL_SHUTDOWN_MASK;
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ret = ltc294x_write_regs(info->client,
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LTC294X_REG_CONTROL, &ctrl_reg, 1);
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if (ret < 0)
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return ret;
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/* Set new charge value */
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dataw[0] = I16_MSB(value);
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dataw[1] = I16_LSB(value);
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ret = ltc294x_write_regs(info->client,
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LTC294X_REG_ACC_CHARGE_MSB, &dataw[0], 2);
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if (ret < 0)
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goto error_exit;
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/* Enable analog section */
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error_exit:
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ctrl_reg &= ~LTC294X_REG_CONTROL_SHUTDOWN_MASK;
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ret = ltc294x_write_regs(info->client,
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LTC294X_REG_CONTROL, &ctrl_reg, 1);
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return ret < 0 ? ret : 0;
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}
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static int ltc294x_get_charge_counter(
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const struct ltc294x_info *info, int *val)
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{
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int value = ltc294x_read_charge_register(info);
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if (value < 0)
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return value;
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value -= LTC294X_MID_SUPPLY;
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*val = convert_bin_to_uAh(info, value);
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return 0;
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}
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static int ltc294x_get_voltage(const struct ltc294x_info *info, int *val)
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{
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int ret;
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u8 datar[2];
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u32 value;
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ret = ltc294x_read_regs(info->client,
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LTC294X_REG_VOLTAGE_MSB, &datar[0], 2);
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value = (datar[0] << 8) | datar[1];
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*val = ((value * 23600) / 0xFFFF) * 1000; /* in uV */
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return ret;
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}
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static int ltc294x_get_current(const struct ltc294x_info *info, int *val)
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{
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int ret;
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u8 datar[2];
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s32 value;
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ret = ltc294x_read_regs(info->client,
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LTC294X_REG_CURRENT_MSB, &datar[0], 2);
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value = (datar[0] << 8) | datar[1];
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value -= 0x7FFF;
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/* Value is in range -32k..+32k, r_sense is usually 10..50 mOhm,
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* the formula below keeps everything in s32 range while preserving
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* enough digits */
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*val = 1000 * ((60000 * value) / (info->r_sense * 0x7FFF)); /* in uA */
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return ret;
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}
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static int ltc294x_get_temperature(const struct ltc294x_info *info, int *val)
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{
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int ret;
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u8 datar[2];
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u32 value;
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ret = ltc294x_read_regs(info->client,
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LTC294X_REG_TEMPERATURE_MSB, &datar[0], 2);
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value = (datar[0] << 8) | datar[1];
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/* Full-scale is 510 Kelvin, convert to centidegrees */
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*val = (((51000 * value) / 0xFFFF) - 27215);
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return ret;
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}
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static int ltc294x_get_property(struct power_supply *psy,
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enum power_supply_property prop,
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union power_supply_propval *val)
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{
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struct ltc294x_info *info = power_supply_get_drvdata(psy);
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switch (prop) {
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case POWER_SUPPLY_PROP_CHARGE_NOW:
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return ltc294x_get_charge_now(info, &val->intval);
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case POWER_SUPPLY_PROP_CHARGE_COUNTER:
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return ltc294x_get_charge_counter(info, &val->intval);
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case POWER_SUPPLY_PROP_VOLTAGE_NOW:
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return ltc294x_get_voltage(info, &val->intval);
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case POWER_SUPPLY_PROP_CURRENT_NOW:
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return ltc294x_get_current(info, &val->intval);
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case POWER_SUPPLY_PROP_TEMP:
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return ltc294x_get_temperature(info, &val->intval);
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default:
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return -EINVAL;
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}
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}
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static int ltc294x_set_property(struct power_supply *psy,
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enum power_supply_property psp,
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const union power_supply_propval *val)
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{
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struct ltc294x_info *info = power_supply_get_drvdata(psy);
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switch (psp) {
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case POWER_SUPPLY_PROP_CHARGE_NOW:
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return ltc294x_set_charge_now(info, val->intval);
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default:
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return -EPERM;
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}
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}
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static int ltc294x_property_is_writeable(
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struct power_supply *psy, enum power_supply_property psp)
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{
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switch (psp) {
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case POWER_SUPPLY_PROP_CHARGE_NOW:
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return 1;
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default:
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return 0;
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}
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}
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static void ltc294x_update(struct ltc294x_info *info)
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{
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int charge = ltc294x_read_charge_register(info);
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if (charge != info->charge) {
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info->charge = charge;
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power_supply_changed(info->supply);
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}
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}
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static void ltc294x_work(struct work_struct *work)
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{
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struct ltc294x_info *info;
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info = container_of(work, struct ltc294x_info, work.work);
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ltc294x_update(info);
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schedule_delayed_work(&info->work, LTC294X_WORK_DELAY * HZ);
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}
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static enum power_supply_property ltc294x_properties[] = {
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POWER_SUPPLY_PROP_CHARGE_COUNTER,
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POWER_SUPPLY_PROP_CHARGE_NOW,
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POWER_SUPPLY_PROP_VOLTAGE_NOW,
|
|
POWER_SUPPLY_PROP_CURRENT_NOW,
|
|
POWER_SUPPLY_PROP_TEMP,
|
|
};
|
|
|
|
static int ltc294x_i2c_remove(struct i2c_client *client)
|
|
{
|
|
struct ltc294x_info *info = i2c_get_clientdata(client);
|
|
|
|
cancel_delayed_work(&info->work);
|
|
power_supply_unregister(info->supply);
|
|
kfree(info->supply_desc.name);
|
|
mutex_lock(<c294x_lock);
|
|
idr_remove(<c294x_id, info->id);
|
|
mutex_unlock(<c294x_lock);
|
|
return 0;
|
|
}
|
|
|
|
static int ltc294x_i2c_probe(struct i2c_client *client,
|
|
const struct i2c_device_id *id)
|
|
{
|
|
struct power_supply_config psy_cfg = {};
|
|
struct ltc294x_info *info;
|
|
int ret;
|
|
int num;
|
|
u32 prescaler_exp;
|
|
s32 r_sense;
|
|
struct device_node *np;
|
|
|
|
mutex_lock(<c294x_lock);
|
|
ret = idr_alloc(<c294x_id, client, 0, 0, GFP_KERNEL);
|
|
mutex_unlock(<c294x_lock);
|
|
if (ret < 0)
|
|
goto fail_id;
|
|
|
|
num = ret;
|
|
|
|
info = devm_kzalloc(&client->dev, sizeof(*info), GFP_KERNEL);
|
|
if (info == NULL) {
|
|
ret = -ENOMEM;
|
|
goto fail_info;
|
|
}
|
|
|
|
i2c_set_clientdata(client, info);
|
|
|
|
info->num_regs = id->driver_data;
|
|
info->supply_desc.name = kasprintf(GFP_KERNEL, "%s-%d", client->name,
|
|
num);
|
|
if (!info->supply_desc.name) {
|
|
ret = -ENOMEM;
|
|
goto fail_name;
|
|
}
|
|
|
|
np = of_node_get(client->dev.of_node);
|
|
|
|
/* r_sense can be negative, when sense+ is connected to the battery
|
|
* instead of the sense-. This results in reversed measurements. */
|
|
ret = of_property_read_u32(np, "lltc,resistor-sense", &r_sense);
|
|
if (ret < 0) {
|
|
dev_err(&client->dev,
|
|
"Could not find lltc,resistor-sense in devicetree\n");
|
|
goto fail_name;
|
|
}
|
|
info->r_sense = r_sense;
|
|
|
|
ret = of_property_read_u32(np, "lltc,prescaler-exponent",
|
|
&prescaler_exp);
|
|
if (ret < 0) {
|
|
dev_warn(&client->dev,
|
|
"lltc,prescaler-exponent not in devicetree\n");
|
|
prescaler_exp = LTC2941_MAX_PRESCALER_EXP;
|
|
}
|
|
|
|
if (info->num_regs == LTC2943_NUM_REGS) {
|
|
if (prescaler_exp > LTC2943_MAX_PRESCALER_EXP)
|
|
prescaler_exp = LTC2943_MAX_PRESCALER_EXP;
|
|
info->Qlsb = ((340 * 50000) / r_sense) /
|
|
(4096 / (1 << (2*prescaler_exp)));
|
|
} else {
|
|
if (prescaler_exp > LTC2941_MAX_PRESCALER_EXP)
|
|
prescaler_exp = LTC2941_MAX_PRESCALER_EXP;
|
|
info->Qlsb = ((85 * 50000) / r_sense) /
|
|
(128 / (1 << prescaler_exp));
|
|
}
|
|
|
|
info->client = client;
|
|
info->id = num;
|
|
info->supply_desc.type = POWER_SUPPLY_TYPE_BATTERY;
|
|
info->supply_desc.properties = ltc294x_properties;
|
|
if (info->num_regs >= LTC294X_REG_TEMPERATURE_LSB)
|
|
info->supply_desc.num_properties =
|
|
ARRAY_SIZE(ltc294x_properties);
|
|
else if (info->num_regs >= LTC294X_REG_CURRENT_LSB)
|
|
info->supply_desc.num_properties =
|
|
ARRAY_SIZE(ltc294x_properties) - 1;
|
|
else if (info->num_regs >= LTC294X_REG_VOLTAGE_LSB)
|
|
info->supply_desc.num_properties =
|
|
ARRAY_SIZE(ltc294x_properties) - 2;
|
|
else
|
|
info->supply_desc.num_properties =
|
|
ARRAY_SIZE(ltc294x_properties) - 3;
|
|
info->supply_desc.get_property = ltc294x_get_property;
|
|
info->supply_desc.set_property = ltc294x_set_property;
|
|
info->supply_desc.property_is_writeable = ltc294x_property_is_writeable;
|
|
info->supply_desc.external_power_changed = NULL;
|
|
|
|
psy_cfg.drv_data = info;
|
|
|
|
INIT_DELAYED_WORK(&info->work, ltc294x_work);
|
|
|
|
ret = ltc294x_reset(info, prescaler_exp);
|
|
if (ret < 0) {
|
|
dev_err(&client->dev, "Communication with chip failed\n");
|
|
goto fail_comm;
|
|
}
|
|
|
|
info->supply = power_supply_register(&client->dev, &info->supply_desc,
|
|
&psy_cfg);
|
|
if (IS_ERR(info->supply)) {
|
|
dev_err(&client->dev, "failed to register ltc2941\n");
|
|
ret = PTR_ERR(info->supply);
|
|
goto fail_register;
|
|
} else {
|
|
schedule_delayed_work(&info->work, LTC294X_WORK_DELAY * HZ);
|
|
}
|
|
|
|
return 0;
|
|
|
|
fail_register:
|
|
kfree(info->supply_desc.name);
|
|
fail_comm:
|
|
fail_name:
|
|
fail_info:
|
|
mutex_lock(<c294x_lock);
|
|
idr_remove(<c294x_id, num);
|
|
mutex_unlock(<c294x_lock);
|
|
fail_id:
|
|
return ret;
|
|
}
|
|
|
|
#ifdef CONFIG_PM_SLEEP
|
|
|
|
static int ltc294x_suspend(struct device *dev)
|
|
{
|
|
struct i2c_client *client = to_i2c_client(dev);
|
|
struct ltc294x_info *info = i2c_get_clientdata(client);
|
|
|
|
cancel_delayed_work(&info->work);
|
|
return 0;
|
|
}
|
|
|
|
static int ltc294x_resume(struct device *dev)
|
|
{
|
|
struct i2c_client *client = to_i2c_client(dev);
|
|
struct ltc294x_info *info = i2c_get_clientdata(client);
|
|
|
|
schedule_delayed_work(&info->work, LTC294X_WORK_DELAY * HZ);
|
|
return 0;
|
|
}
|
|
|
|
static SIMPLE_DEV_PM_OPS(ltc294x_pm_ops, ltc294x_suspend, ltc294x_resume);
|
|
#define LTC294X_PM_OPS (<c294x_pm_ops)
|
|
|
|
#else
|
|
#define LTC294X_PM_OPS NULL
|
|
#endif /* CONFIG_PM_SLEEP */
|
|
|
|
|
|
static const struct i2c_device_id ltc294x_i2c_id[] = {
|
|
{"ltc2941", LTC2941_NUM_REGS},
|
|
{"ltc2943", LTC2943_NUM_REGS},
|
|
{ },
|
|
};
|
|
MODULE_DEVICE_TABLE(i2c, ltc294x_i2c_id);
|
|
|
|
static struct i2c_driver ltc294x_driver = {
|
|
.driver = {
|
|
.name = "LTC2941",
|
|
.pm = LTC294X_PM_OPS,
|
|
},
|
|
.probe = ltc294x_i2c_probe,
|
|
.remove = ltc294x_i2c_remove,
|
|
.id_table = ltc294x_i2c_id,
|
|
};
|
|
module_i2c_driver(ltc294x_driver);
|
|
|
|
MODULE_AUTHOR("Auryn Verwegen, Topic Embedded Systems");
|
|
MODULE_AUTHOR("Mike Looijmans, Topic Embedded Products");
|
|
MODULE_DESCRIPTION("LTC2941/LTC2943 Battery Gas Gauge IC driver");
|
|
MODULE_LICENSE("GPL");
|