linux_dsm_epyc7002/drivers/iio/adc/axp288_adc.c
Hans de Goede fa2849e964 iio: adc: axp288: Drop bogus AXP288_ADC_TS_PIN_CTRL register modifications
For some reason the axp288_adc driver was modifying the
AXP288_ADC_TS_PIN_CTRL register, changing bits 0-1 depending on
whether the GP_ADC channel or another channel was written.

These bits control when a bias current is send to the TS_PIN, the
GP_ADC has its own pin and a separate bit in another register to
control the bias current.

Not only does changing when to enable the TS_PIN bias current
(always or only when sampling) when reading the GP_ADC make no sense
at all, the code is modifying these bits is writing the entire register,
assuming that all the other bits have their default value.

So if the firmware has configured a different bias-current for either
pin, then that change gets clobbered by the write, likewise if the
firmware has set bit 2 to indicate that the battery has no thermal sensor,
this will get clobbered by the write.

This commit fixes all this, by simply removing all writes to the
AXP288_ADC_TS_PIN_CTRL register, they are not needed to read the
GP_ADC pin, and can actually be harmful.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-10 19:54:57 +00:00

232 lines
5.8 KiB
C

/*
* axp288_adc.c - X-Powers AXP288 PMIC ADC Driver
*
* Copyright (C) 2014 Intel Corporation
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/regmap.h>
#include <linux/mfd/axp20x.h>
#include <linux/platform_device.h>
#include <linux/iio/iio.h>
#include <linux/iio/machine.h>
#include <linux/iio/driver.h>
#define AXP288_ADC_EN_MASK 0xF1
enum axp288_adc_id {
AXP288_ADC_TS,
AXP288_ADC_PMIC,
AXP288_ADC_GP,
AXP288_ADC_BATT_CHRG_I,
AXP288_ADC_BATT_DISCHRG_I,
AXP288_ADC_BATT_V,
AXP288_ADC_NR_CHAN,
};
struct axp288_adc_info {
int irq;
struct regmap *regmap;
};
static const struct iio_chan_spec axp288_adc_channels[] = {
{
.indexed = 1,
.type = IIO_TEMP,
.channel = 0,
.address = AXP288_TS_ADC_H,
.datasheet_name = "TS_PIN",
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
}, {
.indexed = 1,
.type = IIO_TEMP,
.channel = 1,
.address = AXP288_PMIC_ADC_H,
.datasheet_name = "PMIC_TEMP",
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
}, {
.indexed = 1,
.type = IIO_TEMP,
.channel = 2,
.address = AXP288_GP_ADC_H,
.datasheet_name = "GPADC",
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
}, {
.indexed = 1,
.type = IIO_CURRENT,
.channel = 3,
.address = AXP20X_BATT_CHRG_I_H,
.datasheet_name = "BATT_CHG_I",
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
}, {
.indexed = 1,
.type = IIO_CURRENT,
.channel = 4,
.address = AXP20X_BATT_DISCHRG_I_H,
.datasheet_name = "BATT_DISCHRG_I",
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
}, {
.indexed = 1,
.type = IIO_VOLTAGE,
.channel = 5,
.address = AXP20X_BATT_V_H,
.datasheet_name = "BATT_V",
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
},
};
#define AXP288_ADC_MAP(_adc_channel_label, _consumer_dev_name, \
_consumer_channel) \
{ \
.adc_channel_label = _adc_channel_label, \
.consumer_dev_name = _consumer_dev_name, \
.consumer_channel = _consumer_channel, \
}
/* for consumer drivers */
static struct iio_map axp288_adc_default_maps[] = {
AXP288_ADC_MAP("TS_PIN", "axp288-batt", "axp288-batt-temp"),
AXP288_ADC_MAP("PMIC_TEMP", "axp288-pmic", "axp288-pmic-temp"),
AXP288_ADC_MAP("GPADC", "axp288-gpadc", "axp288-system-temp"),
AXP288_ADC_MAP("BATT_CHG_I", "axp288-chrg", "axp288-chrg-curr"),
AXP288_ADC_MAP("BATT_DISCHRG_I", "axp288-chrg", "axp288-chrg-d-curr"),
AXP288_ADC_MAP("BATT_V", "axp288-batt", "axp288-batt-volt"),
{},
};
static int axp288_adc_read_channel(int *val, unsigned long address,
struct regmap *regmap)
{
u8 buf[2];
if (regmap_bulk_read(regmap, address, buf, 2))
return -EIO;
*val = (buf[0] << 4) + ((buf[1] >> 4) & 0x0F);
return IIO_VAL_INT;
}
static int axp288_adc_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val, int *val2, long mask)
{
int ret;
struct axp288_adc_info *info = iio_priv(indio_dev);
mutex_lock(&indio_dev->mlock);
switch (mask) {
case IIO_CHAN_INFO_RAW:
ret = axp288_adc_read_channel(val, chan->address, info->regmap);
break;
default:
ret = -EINVAL;
}
mutex_unlock(&indio_dev->mlock);
return ret;
}
static const struct iio_info axp288_adc_iio_info = {
.read_raw = &axp288_adc_read_raw,
.driver_module = THIS_MODULE,
};
static int axp288_adc_probe(struct platform_device *pdev)
{
int ret;
struct axp288_adc_info *info;
struct iio_dev *indio_dev;
struct axp20x_dev *axp20x = dev_get_drvdata(pdev->dev.parent);
indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*info));
if (!indio_dev)
return -ENOMEM;
info = iio_priv(indio_dev);
info->irq = platform_get_irq(pdev, 0);
if (info->irq < 0) {
dev_err(&pdev->dev, "no irq resource?\n");
return info->irq;
}
platform_set_drvdata(pdev, indio_dev);
info->regmap = axp20x->regmap;
/*
* Set ADC to enabled state at all time, including system suspend.
* otherwise internal fuel gauge functionality may be affected.
*/
ret = regmap_write(info->regmap, AXP20X_ADC_EN1, AXP288_ADC_EN_MASK);
if (ret) {
dev_err(&pdev->dev, "unable to enable ADC device\n");
return ret;
}
indio_dev->dev.parent = &pdev->dev;
indio_dev->name = pdev->name;
indio_dev->channels = axp288_adc_channels;
indio_dev->num_channels = ARRAY_SIZE(axp288_adc_channels);
indio_dev->info = &axp288_adc_iio_info;
indio_dev->modes = INDIO_DIRECT_MODE;
ret = iio_map_array_register(indio_dev, axp288_adc_default_maps);
if (ret < 0)
return ret;
ret = iio_device_register(indio_dev);
if (ret < 0) {
dev_err(&pdev->dev, "unable to register iio device\n");
goto err_array_unregister;
}
return 0;
err_array_unregister:
iio_map_array_unregister(indio_dev);
return ret;
}
static int axp288_adc_remove(struct platform_device *pdev)
{
struct iio_dev *indio_dev = platform_get_drvdata(pdev);
iio_device_unregister(indio_dev);
iio_map_array_unregister(indio_dev);
return 0;
}
static const struct platform_device_id axp288_adc_id_table[] = {
{ .name = "axp288_adc" },
{},
};
static struct platform_driver axp288_adc_driver = {
.probe = axp288_adc_probe,
.remove = axp288_adc_remove,
.id_table = axp288_adc_id_table,
.driver = {
.name = "axp288_adc",
},
};
MODULE_DEVICE_TABLE(platform, axp288_adc_id_table);
module_platform_driver(axp288_adc_driver);
MODULE_AUTHOR("Jacob Pan <jacob.jun.pan@linux.intel.com>");
MODULE_DESCRIPTION("X-Powers AXP288 ADC Driver");
MODULE_LICENSE("GPL");