blob: 550b9081fcbc2f93ff0cf17714211b0ab6f949c1 [file] [log] [blame]
// 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>
struct pch_fivr_resp {
u64 status;
u64 result;
};
static int pch_fivr_read(acpi_handle handle, char *method, struct pch_fivr_resp *fivr_resp)
{
struct acpi_buffer resp = { sizeof(struct pch_fivr_resp), fivr_resp};
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
struct acpi_buffer format = { sizeof("NN"), "NN" };
union acpi_object *obj;
acpi_status status;
int ret = -EFAULT;
status = acpi_evaluate_object(handle, method, NULL, &buffer);
if (ACPI_FAILURE(status))
return ret;
obj = buffer.pointer;
if (!obj || obj->type != ACPI_TYPE_PACKAGE)
goto release_buffer;
status = acpi_extract_package(obj, &format, &resp);
if (ACPI_FAILURE(status))
goto release_buffer;
if (fivr_resp->status)
goto release_buffer;
ret = 0;
release_buffer:
kfree(buffer.pointer);
return ret;
}
/*
* 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);\
struct pch_fivr_resp fivr_resp;\
int status;\
\
status = pch_fivr_read(acpi_dev->handle, #method, &fivr_resp);\
if (status)\
return status;\
\
return sprintf(buf, "%llu\n", fivr_resp.result);\
}
#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");