swh:1:snp:173f8deb0c56c557784b4fd217e7608ac6197844
Tip revision: 19c329f6808995b142b3966301f217c831e7cf31 authored by Linus Torvalds on 18 January 2021, 00:37:05 UTC
Linux 5.11-rc4
Linux 5.11-rc4
Tip revision: 19c329f
dptf_pch_fivr.c
// SPDX-License-Identifier: GPL-2.0-only
/*
* dptf_pch_fivr: DPTF PCH FIVR Participant driver
* Copyright (c) 2020, Intel Corporation.
*/
#include <linux/acpi.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
/*
* Presentation of attributes which are defined for INT1045
* They are:
* freq_mhz_low_clock : Set PCH FIVR switching freq for
* FIVR clock 19.2MHz and 24MHz
* freq_mhz_high_clock : Set PCH FIVR switching freq for
* FIVR clock 38.4MHz
*/
#define PCH_FIVR_SHOW(name, method) \
static ssize_t name##_show(struct device *dev,\
struct device_attribute *attr,\
char *buf)\
{\
struct acpi_device *acpi_dev = dev_get_drvdata(dev);\
unsigned long long val;\
acpi_status status;\
\
status = acpi_evaluate_integer(acpi_dev->handle, #method,\
NULL, &val);\
if (ACPI_SUCCESS(status))\
return sprintf(buf, "%d\n", (int)val);\
else\
return -EINVAL;\
}
#define PCH_FIVR_STORE(name, method) \
static ssize_t name##_store(struct device *dev,\
struct device_attribute *attr,\
const char *buf, size_t count)\
{\
struct acpi_device *acpi_dev = dev_get_drvdata(dev);\
acpi_status status;\
u32 val;\
\
if (kstrtouint(buf, 0, &val) < 0)\
return -EINVAL;\
\
status = acpi_execute_simple_method(acpi_dev->handle, #method, val);\
if (ACPI_SUCCESS(status))\
return count;\
\
return -EINVAL;\
}
PCH_FIVR_SHOW(freq_mhz_low_clock, GFC0)
PCH_FIVR_SHOW(freq_mhz_high_clock, GFC1)
PCH_FIVR_STORE(freq_mhz_low_clock, RFC0)
PCH_FIVR_STORE(freq_mhz_high_clock, RFC1)
static DEVICE_ATTR_RW(freq_mhz_low_clock);
static DEVICE_ATTR_RW(freq_mhz_high_clock);
static struct attribute *fivr_attrs[] = {
&dev_attr_freq_mhz_low_clock.attr,
&dev_attr_freq_mhz_high_clock.attr,
NULL
};
static const struct attribute_group pch_fivr_attribute_group = {
.attrs = fivr_attrs,
.name = "pch_fivr_switch_frequency"
};
static int pch_fivr_add(struct platform_device *pdev)
{
struct acpi_device *acpi_dev;
unsigned long long ptype;
acpi_status status;
int result;
acpi_dev = ACPI_COMPANION(&(pdev->dev));
if (!acpi_dev)
return -ENODEV;
status = acpi_evaluate_integer(acpi_dev->handle, "PTYP", NULL, &ptype);
if (ACPI_FAILURE(status) || ptype != 0x05)
return -ENODEV;
result = sysfs_create_group(&pdev->dev.kobj,
&pch_fivr_attribute_group);
if (result)
return result;
platform_set_drvdata(pdev, acpi_dev);
return 0;
}
static int pch_fivr_remove(struct platform_device *pdev)
{
sysfs_remove_group(&pdev->dev.kobj, &pch_fivr_attribute_group);
return 0;
}
static const struct acpi_device_id pch_fivr_device_ids[] = {
{"INTC1045", 0},
{"INTC1049", 0},
{"", 0},
};
MODULE_DEVICE_TABLE(acpi, pch_fivr_device_ids);
static struct platform_driver pch_fivr_driver = {
.probe = pch_fivr_add,
.remove = pch_fivr_remove,
.driver = {
.name = "dptf_pch_fivr",
.acpi_match_table = pch_fivr_device_ids,
},
};
module_platform_driver(pch_fivr_driver);
MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("ACPI DPTF PCH FIVR driver");