linux_dsm_epyc7002/drivers/acpi/pmic/intel_pmic_xpower.c
Hans de Goede 3c670dba86 ACPI / PMIC: xpower: Block P-Unit I2C access during read-modify-write
intel_xpower_pmic_update_power() does a read-modify-write of the output
control register. The i2c-designware code blocks the P-Unit I2C access
during the read and write by taking the P-Unit's PMIC bus semaphore.
But between the read and the write that semaphore is released and the
P-Unit could make changes to the register which we then end up overwriting.

This commit makes intel_xpower_pmic_update_power() take the semaphore
itself so that it is held over the entire read-modify-write, avoiding this
race.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-10-25 17:00:05 +02:00

283 lines
5.4 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* XPower AXP288 PMIC operation region driver
*
* Copyright (C) 2014 Intel Corporation. All rights reserved.
*/
#include <linux/acpi.h>
#include <linux/init.h>
#include <linux/mfd/axp20x.h>
#include <linux/regmap.h>
#include <linux/platform_device.h>
#include <asm/iosf_mbi.h>
#include "intel_pmic.h"
#define XPOWER_GPADC_LOW 0x5b
#define XPOWER_GPI1_CTRL 0x92
#define GPI1_LDO_MASK GENMASK(2, 0)
#define GPI1_LDO_ON (3 << 0)
#define GPI1_LDO_OFF (4 << 0)
#define AXP288_ADC_TS_PIN_GPADC 0xf2
#define AXP288_ADC_TS_PIN_ON 0xf3
static struct pmic_table power_table[] = {
{
.address = 0x00,
.reg = 0x13,
.bit = 0x05,
}, /* ALD1 */
{
.address = 0x04,
.reg = 0x13,
.bit = 0x06,
}, /* ALD2 */
{
.address = 0x08,
.reg = 0x13,
.bit = 0x07,
}, /* ALD3 */
{
.address = 0x0c,
.reg = 0x12,
.bit = 0x03,
}, /* DLD1 */
{
.address = 0x10,
.reg = 0x12,
.bit = 0x04,
}, /* DLD2 */
{
.address = 0x14,
.reg = 0x12,
.bit = 0x05,
}, /* DLD3 */
{
.address = 0x18,
.reg = 0x12,
.bit = 0x06,
}, /* DLD4 */
{
.address = 0x1c,
.reg = 0x12,
.bit = 0x00,
}, /* ELD1 */
{
.address = 0x20,
.reg = 0x12,
.bit = 0x01,
}, /* ELD2 */
{
.address = 0x24,
.reg = 0x12,
.bit = 0x02,
}, /* ELD3 */
{
.address = 0x28,
.reg = 0x13,
.bit = 0x02,
}, /* FLD1 */
{
.address = 0x2c,
.reg = 0x13,
.bit = 0x03,
}, /* FLD2 */
{
.address = 0x30,
.reg = 0x13,
.bit = 0x04,
}, /* FLD3 */
{
.address = 0x34,
.reg = 0x10,
.bit = 0x03,
}, /* BUC1 */
{
.address = 0x38,
.reg = 0x10,
.bit = 0x06,
}, /* BUC2 */
{
.address = 0x3c,
.reg = 0x10,
.bit = 0x05,
}, /* BUC3 */
{
.address = 0x40,
.reg = 0x10,
.bit = 0x04,
}, /* BUC4 */
{
.address = 0x44,
.reg = 0x10,
.bit = 0x01,
}, /* BUC5 */
{
.address = 0x48,
.reg = 0x10,
.bit = 0x00
}, /* BUC6 */
{
.address = 0x4c,
.reg = 0x92,
}, /* GPI1 */
};
/* TMP0 - TMP5 are the same, all from GPADC */
static struct pmic_table thermal_table[] = {
{
.address = 0x00,
.reg = XPOWER_GPADC_LOW
},
{
.address = 0x0c,
.reg = XPOWER_GPADC_LOW
},
{
.address = 0x18,
.reg = XPOWER_GPADC_LOW
},
{
.address = 0x24,
.reg = XPOWER_GPADC_LOW
},
{
.address = 0x30,
.reg = XPOWER_GPADC_LOW
},
{
.address = 0x3c,
.reg = XPOWER_GPADC_LOW
},
};
static int intel_xpower_pmic_get_power(struct regmap *regmap, int reg,
int bit, u64 *value)
{
int data;
if (regmap_read(regmap, reg, &data))
return -EIO;
/* GPIO1 LDO regulator needs special handling */
if (reg == XPOWER_GPI1_CTRL)
*value = ((data & GPI1_LDO_MASK) == GPI1_LDO_ON);
else
*value = (data & BIT(bit)) ? 1 : 0;
return 0;
}
static int intel_xpower_pmic_update_power(struct regmap *regmap, int reg,
int bit, bool on)
{
int data, ret;
/* GPIO1 LDO regulator needs special handling */
if (reg == XPOWER_GPI1_CTRL)
return regmap_update_bits(regmap, reg, GPI1_LDO_MASK,
on ? GPI1_LDO_ON : GPI1_LDO_OFF);
ret = iosf_mbi_block_punit_i2c_access();
if (ret)
return ret;
if (regmap_read(regmap, reg, &data)) {
ret = -EIO;
goto out;
}
if (on)
data |= BIT(bit);
else
data &= ~BIT(bit);
if (regmap_write(regmap, reg, data))
ret = -EIO;
out:
iosf_mbi_unblock_punit_i2c_access();
return ret;
}
/**
* intel_xpower_pmic_get_raw_temp(): Get raw temperature reading from the PMIC
*
* @regmap: regmap of the PMIC device
* @reg: register to get the reading
*
* Return a positive value on success, errno on failure.
*/
static int intel_xpower_pmic_get_raw_temp(struct regmap *regmap, int reg)
{
u8 buf[2];
int ret;
ret = regmap_write(regmap, AXP288_ADC_TS_PIN_CTRL,
AXP288_ADC_TS_PIN_GPADC);
if (ret)
return ret;
/* After switching to the GPADC pin give things some time to settle */
usleep_range(6000, 10000);
ret = regmap_bulk_read(regmap, AXP288_GP_ADC_H, buf, 2);
if (ret == 0)
ret = (buf[0] << 4) + ((buf[1] >> 4) & 0x0f);
regmap_write(regmap, AXP288_ADC_TS_PIN_CTRL, AXP288_ADC_TS_PIN_ON);
return ret;
}
static struct intel_pmic_opregion_data intel_xpower_pmic_opregion_data = {
.get_power = intel_xpower_pmic_get_power,
.update_power = intel_xpower_pmic_update_power,
.get_raw_temp = intel_xpower_pmic_get_raw_temp,
.power_table = power_table,
.power_table_count = ARRAY_SIZE(power_table),
.thermal_table = thermal_table,
.thermal_table_count = ARRAY_SIZE(thermal_table),
};
static acpi_status intel_xpower_pmic_gpio_handler(u32 function,
acpi_physical_address address, u32 bit_width, u64 *value,
void *handler_context, void *region_context)
{
return AE_OK;
}
static int intel_xpower_pmic_opregion_probe(struct platform_device *pdev)
{
struct device *parent = pdev->dev.parent;
struct axp20x_dev *axp20x = dev_get_drvdata(parent);
acpi_status status;
int result;
status = acpi_install_address_space_handler(ACPI_HANDLE(parent),
ACPI_ADR_SPACE_GPIO, intel_xpower_pmic_gpio_handler,
NULL, NULL);
if (ACPI_FAILURE(status))
return -ENODEV;
result = intel_pmic_install_opregion_handler(&pdev->dev,
ACPI_HANDLE(parent), axp20x->regmap,
&intel_xpower_pmic_opregion_data);
if (result)
acpi_remove_address_space_handler(ACPI_HANDLE(parent),
ACPI_ADR_SPACE_GPIO,
intel_xpower_pmic_gpio_handler);
return result;
}
static struct platform_driver intel_xpower_pmic_opregion_driver = {
.probe = intel_xpower_pmic_opregion_probe,
.driver = {
.name = "axp288_pmic_acpi",
},
};
builtin_platform_driver(intel_xpower_pmic_opregion_driver);