linux/drivers/misc/lis3lv02d/lis3lv02d_i2c.c
Hans de Goede ac3e038407 misc: lis3lv02d_i2c: Fix regulators getting en-/dis-abled twice on suspend/resume
When not configured for wakeup lis3lv02d_i2c_suspend() will call
lis3lv02d_poweroff() even if the device has already been turned off
by the runtime-suspend handler and if configured for wakeup and
the device is runtime-suspended at this point then it is not turned
back on to serve as a wakeup source.

Before commit b1b9f7a494 ("misc: lis3lv02d_i2c: Add missing setting
of the reg_ctrl callback"), lis3lv02d_poweroff() failed to disable
the regulators which as a side effect made calling poweroff() twice ok.

Now that poweroff() correctly disables the regulators, doing this twice
triggers a WARN() in the regulator core:

unbalanced disables for regulator-dummy
WARNING: CPU: 1 PID: 92 at drivers/regulator/core.c:2999 _regulator_disable
...

Fix lis3lv02d_i2c_suspend() to not call poweroff() a second time if
already runtime-suspended and add a poweron() call when necessary to
make wakeup work.

lis3lv02d_i2c_resume() has similar issues, with an added weirness that
it always powers on the device if it is runtime suspended, after which
the first runtime-resume will call poweron() again, causing the enabled
count for the regulator to increase by 1 every suspend/resume. These
unbalanced regulator_enable() calls cause the regulator to never
be turned off and trigger the following WARN() on driver unbind:

WARNING: CPU: 1 PID: 1724 at drivers/regulator/core.c:2396 _regulator_put

Fix this by making lis3lv02d_i2c_resume() mirror the new suspend().

Fixes: b1b9f7a494 ("misc: lis3lv02d_i2c: Add missing setting of the reg_ctrl callback")
Reported-by: Paul Menzel <pmenzel@molgen.mpg.de>
Closes: https://lore.kernel.org/regressions/5fc6da74-af0a-4aac-b4d5-a000b39a63a5@molgen.mpg.de/
Cc: stable@vger.kernel.org
Cc: regressions@lists.linux.dev
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Tested-by: Paul Menzel <pmenzel@molgen.mpg.de> # Dell XPS 15 7590
Reviewed-by: Paul Menzel <pmenzel@molgen.mpg.de>
Link: https://lore.kernel.org/r/20240220190035.53402-1-hdegoede@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-04 07:59:43 +01:00

281 lines
6.9 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* drivers/hwmon/lis3lv02d_i2c.c
*
* Implements I2C interface for lis3lv02d (STMicroelectronics) accelerometer.
* Driver is based on corresponding SPI driver written by Daniel Mack
* (lis3lv02d_spi.c (C) 2009 Daniel Mack <daniel@caiaq.de> ).
*
* Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
*
* Contact: Samu Onkalo <samu.p.onkalo@nokia.com>
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/pm_runtime.h>
#include <linux/delay.h>
#include <linux/of.h>
#include <linux/of_platform.h>
#include <linux/of_device.h>
#include "lis3lv02d.h"
#define DRV_NAME "lis3lv02d_i2c"
static const char reg_vdd[] = "Vdd";
static const char reg_vdd_io[] = "Vdd_IO";
static int lis3_reg_ctrl(struct lis3lv02d *lis3, bool state)
{
int ret;
if (state == LIS3_REG_OFF) {
ret = regulator_bulk_disable(ARRAY_SIZE(lis3->regulators),
lis3->regulators);
} else {
ret = regulator_bulk_enable(ARRAY_SIZE(lis3->regulators),
lis3->regulators);
/* Chip needs time to wakeup. Not mentioned in datasheet */
usleep_range(10000, 20000);
}
return ret;
}
static inline s32 lis3_i2c_write(struct lis3lv02d *lis3, int reg, u8 value)
{
struct i2c_client *c = lis3->bus_priv;
return i2c_smbus_write_byte_data(c, reg, value);
}
static inline s32 lis3_i2c_read(struct lis3lv02d *lis3, int reg, u8 *v)
{
struct i2c_client *c = lis3->bus_priv;
*v = i2c_smbus_read_byte_data(c, reg);
return 0;
}
static inline s32 lis3_i2c_blockread(struct lis3lv02d *lis3, int reg, int len,
u8 *v)
{
struct i2c_client *c = lis3->bus_priv;
reg |= (1 << 7); /* 7th bit enables address auto incrementation */
return i2c_smbus_read_i2c_block_data(c, reg, len, v);
}
static int lis3_i2c_init(struct lis3lv02d *lis3)
{
u8 reg;
int ret;
lis3_reg_ctrl(lis3, LIS3_REG_ON);
lis3->read(lis3, WHO_AM_I, &reg);
if (reg != lis3->whoami)
printk(KERN_ERR "lis3: power on failure\n");
/* power up the device */
ret = lis3->read(lis3, CTRL_REG1, &reg);
if (ret < 0)
return ret;
if (lis3->whoami == WAI_3DLH)
reg |= CTRL1_PM0 | CTRL1_Xen | CTRL1_Yen | CTRL1_Zen;
else
reg |= CTRL1_PD0 | CTRL1_Xen | CTRL1_Yen | CTRL1_Zen;
return lis3->write(lis3, CTRL_REG1, reg);
}
/* Default axis mapping but it can be overwritten by platform data */
static union axis_conversion lis3lv02d_axis_map =
{ .as_array = { LIS3_DEV_X, LIS3_DEV_Y, LIS3_DEV_Z } };
#ifdef CONFIG_OF
static const struct of_device_id lis3lv02d_i2c_dt_ids[] = {
{ .compatible = "st,lis3lv02d" },
{}
};
MODULE_DEVICE_TABLE(of, lis3lv02d_i2c_dt_ids);
#endif
static int lis3lv02d_i2c_probe(struct i2c_client *client)
{
int ret = 0;
struct lis3lv02d_platform_data *pdata = client->dev.platform_data;
#ifdef CONFIG_OF
if (of_match_device(lis3lv02d_i2c_dt_ids, &client->dev)) {
lis3_dev.of_node = client->dev.of_node;
ret = lis3lv02d_init_dt(&lis3_dev);
if (ret)
return ret;
pdata = lis3_dev.pdata;
}
#endif
if (pdata) {
if ((pdata->driver_features & LIS3_USE_BLOCK_READ) &&
(i2c_check_functionality(client->adapter,
I2C_FUNC_SMBUS_I2C_BLOCK)))
lis3_dev.blkread = lis3_i2c_blockread;
if (pdata->axis_x)
lis3lv02d_axis_map.x = pdata->axis_x;
if (pdata->axis_y)
lis3lv02d_axis_map.y = pdata->axis_y;
if (pdata->axis_z)
lis3lv02d_axis_map.z = pdata->axis_z;
if (pdata->setup_resources)
ret = pdata->setup_resources();
if (ret)
goto fail;
}
lis3_dev.regulators[0].supply = reg_vdd;
lis3_dev.regulators[1].supply = reg_vdd_io;
ret = regulator_bulk_get(&client->dev,
ARRAY_SIZE(lis3_dev.regulators),
lis3_dev.regulators);
if (ret < 0)
goto fail;
lis3_dev.pdata = pdata;
lis3_dev.bus_priv = client;
lis3_dev.init = lis3_i2c_init;
lis3_dev.read = lis3_i2c_read;
lis3_dev.write = lis3_i2c_write;
lis3_dev.reg_ctrl = lis3_reg_ctrl;
lis3_dev.irq = client->irq;
lis3_dev.ac = lis3lv02d_axis_map;
lis3_dev.pm_dev = &client->dev;
i2c_set_clientdata(client, &lis3_dev);
/* Provide power over the init call */
lis3_reg_ctrl(&lis3_dev, LIS3_REG_ON);
ret = lis3lv02d_init_device(&lis3_dev);
lis3_reg_ctrl(&lis3_dev, LIS3_REG_OFF);
if (ret)
goto fail2;
return 0;
fail2:
regulator_bulk_free(ARRAY_SIZE(lis3_dev.regulators),
lis3_dev.regulators);
fail:
if (pdata && pdata->release_resources)
pdata->release_resources();
return ret;
}
static void lis3lv02d_i2c_remove(struct i2c_client *client)
{
struct lis3lv02d *lis3 = i2c_get_clientdata(client);
struct lis3lv02d_platform_data *pdata = client->dev.platform_data;
if (pdata && pdata->release_resources)
pdata->release_resources();
lis3lv02d_joystick_disable(lis3);
lis3lv02d_remove_fs(&lis3_dev);
regulator_bulk_free(ARRAY_SIZE(lis3->regulators),
lis3_dev.regulators);
}
#ifdef CONFIG_PM_SLEEP
static int lis3lv02d_i2c_suspend(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct lis3lv02d *lis3 = i2c_get_clientdata(client);
/* Turn on for wakeup if turned off by runtime suspend */
if (lis3->pdata && lis3->pdata->wakeup_flags) {
if (pm_runtime_suspended(dev))
lis3lv02d_poweron(lis3);
/* For non wakeup turn off if not already turned off by runtime suspend */
} else if (!pm_runtime_suspended(dev))
lis3lv02d_poweroff(lis3);
return 0;
}
static int lis3lv02d_i2c_resume(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct lis3lv02d *lis3 = i2c_get_clientdata(client);
/* Turn back off if turned on for wakeup and runtime suspended*/
if (lis3->pdata && lis3->pdata->wakeup_flags) {
if (pm_runtime_suspended(dev))
lis3lv02d_poweroff(lis3);
/* For non wakeup turn back on if not runtime suspended */
} else if (!pm_runtime_suspended(dev))
lis3lv02d_poweron(lis3);
return 0;
}
#endif /* CONFIG_PM_SLEEP */
#ifdef CONFIG_PM
static int lis3_i2c_runtime_suspend(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct lis3lv02d *lis3 = i2c_get_clientdata(client);
lis3lv02d_poweroff(lis3);
return 0;
}
static int lis3_i2c_runtime_resume(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct lis3lv02d *lis3 = i2c_get_clientdata(client);
lis3lv02d_poweron(lis3);
return 0;
}
#endif /* CONFIG_PM */
static const struct i2c_device_id lis3lv02d_id[] = {
{"lis3lv02d", LIS3LV02D},
{"lis331dlh", LIS331DLH},
{}
};
MODULE_DEVICE_TABLE(i2c, lis3lv02d_id);
static const struct dev_pm_ops lis3_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(lis3lv02d_i2c_suspend,
lis3lv02d_i2c_resume)
SET_RUNTIME_PM_OPS(lis3_i2c_runtime_suspend,
lis3_i2c_runtime_resume,
NULL)
};
static struct i2c_driver lis3lv02d_i2c_driver = {
.driver = {
.name = DRV_NAME,
.pm = &lis3_pm_ops,
.of_match_table = of_match_ptr(lis3lv02d_i2c_dt_ids),
},
.probe = lis3lv02d_i2c_probe,
.remove = lis3lv02d_i2c_remove,
.id_table = lis3lv02d_id,
};
module_i2c_driver(lis3lv02d_i2c_driver);
MODULE_AUTHOR("Nokia Corporation");
MODULE_DESCRIPTION("lis3lv02d I2C interface");
MODULE_LICENSE("GPL");