// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2021, Intel Corporation.
*/
#include <linux/acpi.h>
#include <linux/kobject.h>
#include <linux/platform_device.h>
#include <linux/sysfs.h>
#include "intel_sar.h"
/**
* get_int_value: Retrieve integer values from ACPI Object
* @obj: acpi_object pointer which has the integer value
* @out: output pointer will get integer value
*
* Function is used to retrieve integer value from acpi object.
*
* Return:
* * 0 on success
* * -EIO if there is an issue in acpi_object passed.
*/
static int get_int_value(union acpi_object *obj, int *out)
{
if (!obj || obj->type != ACPI_TYPE_INTEGER)
return -EIO;
*out = (int)obj->integer.value;
return 0;
}
/**
* update_sar_data: sar data is updated based on regulatory mode
* @context: pointer to driver context structure
*
* sar_data is updated based on regulatory value
* context->reg_value will never exceed MAX_REGULATORY
*/
static void update_sar_data(struct wwan_sar_context *context)
{
struct wwan_device_mode_configuration *config =
&context->config_data[context->reg_value];
if (config->device_mode_info &&
context->sar_data.device_mode < config->total_dev_mode) {
int itr = 0;
for (itr = 0; itr < config->total_dev_mode; itr++) {
if (context->sar_data.device_mode ==
config->device_mode_info[itr].device_mode) {
struct wwan_device_mode_info *dev_mode =
&config->device_mode_info[itr];
context->sar_data.antennatable_index = dev_mode->antennatable_index;
context->sar_data.bandtable_index = dev_mode->bandtable_index;
context->sar_data.sartable_index = dev_mode->sartable_index;
break;
}
}
}
}
/**
* parse_package: parse acpi package for retrieving SAR information
* @context: pointer to driver context structure
* @item : acpi_object pointer
*
* Given acpi_object is iterated to retrieve information for each device mode.
* If a given package corresponding to a specific device mode is faulty, it is
* skipped and the specific entry in context structure will have the default value
* of zero. Decoding of subsequent device modes is realized by having "continue"
* statements in the for loop on encountering error in parsing given device mode.
*
* Return:
* AE_OK if success
* AE_ERROR on error
*/
static acpi_status parse_package(struct wwan_sar_context *context, union acpi_object *item)
{
struct wwan_device_mode_configuration *data;
int value, itr, reg;
union acpi_object *num;
num = &item->package.elements[0];
if (get_int_value(num, &value) || value < 0 || value >= MAX_REGULATORY)
return AE_ERROR;
reg = value;
data = &context->config_data[reg];
if (data->total_dev_mode > MAX_DEV_MODES || data->total_dev_mode == 0 ||
item->package.count <= data->total_dev_mode)
return AE_ERROR;
data->device_mode_info = kmalloc_array(data->total_dev_mode,
sizeof(struct wwan_device_mode_info), GFP_KERNEL);
if (!data->device_mode_info)
return AE_ERROR;
for (itr = 0; itr < data->total_dev_mode; itr++) {
struct wwan_device_mode_info temp = { 0 };
num = &item->package.elements[itr + 1];
if (num->type != ACPI_TYPE_PACKAGE || num->package.count < TOTAL_DATA)
continue;
if (get_int_value(&num->package.elements[0], &temp.device_mode))
continue;
if (get_int_value(&num->package.elements[1], &temp.bandtable_index))
continue;
if (get_int_value(&num->package.elements[2], &temp.antennatable_index))
continue;
if (get_int_value(&num->package.elements[3], &temp.sartable_index))
continue;
data->device_mode_info[itr] = temp;
}
return AE_OK;
}
/**
* sar_get_device_mode: Extraction of information from BIOS via DSM calls
* @device: ACPI device for which to retrieve the data
*
* Retrieve the current device mode information from the BIOS.
*
* Return:
* AE_OK on success
* AE_ERROR on error
*/
static acpi_status sar_get_device_mode(struct platform_device *device)
{
struct wwan_sar_context *context = dev_get_drvdata(&device->dev);
acpi_status status = AE_OK;
union acpi_object *out;
u32 rev = 0;
out = acpi_evaluate_dsm_typed(context->handle, &context->guid, rev,
COMMAND_ID_DEV_MODE, NULL, ACPI_TYPE_INTEGER);
if (!out) {
dev_err(&device->dev, "DSM cmd:%d Failed to retrieve value\n", COMMAND_ID_DEV_MODE);
status = AE_ERROR;
goto dev_mode_error;
}
context->sar_data.device_mode = out->integer.value;
update_sar_data(context);
sysfs_notify(&device->dev.kobj, NULL, SYSFS_DATANAME);
dev_mode_error:
ACPI_FREE(out);
return status;
}
static const struct acpi_device_id sar_device_ids[] = {
{ "INTC1092", 0},
{}
};
MODULE_DEVICE_TABLE(acpi, sar_device_ids);
static ssize_t intc_data_show(struct device *dev, struct device_attribute *attr, char *buf)
{
struct wwan_sar_context *context = dev_get_drvdata(dev);
return sysfs_emit(buf, "%d %d %d %d\n", context->sar_data.device_mode,
context->sar_data.bandtable_index,
context->sar_data.antennatable_index,
context->sar_data.sartable_index);
}
static DEVICE_ATTR_RO(intc_data);
static ssize_t intc_reg_show(struct device *dev, struct device_attribute *attr, char *buf)
{
struct wwan_sar_context *context = dev_get_drvdata(dev);
return sysfs_emit(buf, "%d\n", context->reg_value);
}
static ssize_t intc_reg_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct wwan_sar_context *context = dev_get_drvdata(dev);
unsigned int value;
int read;
if (!count)
return -EINVAL;
read = kstrtouint(buf, 10, &value);
if (read < 0)
return read;
if (value >= MAX_REGULATORY)
return -EOVERFLOW;
context->reg_value = value;
update_sar_data(context);
sysfs_notify(&dev->kobj, NULL, SYSFS_DATANAME);
return count;
}
static DEVICE_ATTR_RW(intc_reg);
static struct attribute *intcsar_attrs[] = {
&dev_attr_intc_data.attr,
&dev_attr_intc_reg.attr,
NULL
};
static struct attribute_group intcsar_group = {
.attrs = intcsar_attrs,
};
static void sar_notify(acpi_handle handle, u32 event, void *data)
{
struct platform_device *device = data;
if (event == SAR_EVENT) {
if (sar_get_device_mode(device) != AE_OK)
dev_err(&device->dev, "sar_get_device_mode error");
}
}
static void sar_get_data(int reg, struct wwan_sar_context *context)
{
union acpi_object *out, req;
u32 rev = 0;
req.type = ACPI_TYPE_INTEGER;
req.integer.value = reg;
out = acpi_evaluate_dsm_typed(context->handle, &context->guid, rev,
COMMAND_ID_CONFIG_TABLE, &req, ACPI_TYPE_PACKAGE);
if (!out)
return;
if (out->package.count >= 3 &&
out->package.elements[0].type == ACPI_TYPE_INTEGER &&
out->package.elements[1].type == ACPI_TYPE_INTEGER &&
out->package.elements[2].type == ACPI_TYPE_PACKAGE &&
out->package.elements[2].package.count > 0) {
context->config_data[reg].version = out->package.elements[0].integer.value;
context->config_data[reg].total_dev_mode =
out->package.elements[1].integer.value;
if (context->config_data[reg].total_dev_mode <= 0 ||
context->config_data[reg].total_dev_mode > MAX_DEV_MODES) {
ACPI_FREE(out);
return;
}
parse_package(context, &out->package.elements[2]);
}
ACPI_FREE(out);
}
static int sar_probe(struct platform_device *device)
{
struct wwan_sar_context *context;
int reg;
int result;
context = kzalloc(sizeof(*context), GFP_KERNEL);
if (!context)
return -ENOMEM;
context->sar_device = device;
context->handle = ACPI_HANDLE(&device->dev);
dev_set_drvdata(&device->dev, context);
result = guid_parse(SAR_DSM_UUID, &context->guid);
if (result) {
dev_err(&device->dev, "SAR UUID parse error: %d\n", result);
goto r_free;
}
for (reg = 0; reg < MAX_REGULATORY; reg++)
sar_get_data(reg, context);
if (sar_get_device_mode(device) != AE_OK) {
dev_err(&device->dev, "Failed to get device mode\n");
result = -EIO;
goto r_free;
}
result = sysfs_create_group(&device->dev.kobj, &intcsar_group);
if (result) {
dev_err(&device->dev, "sysfs creation failed\n");
goto r_free;
}
if (acpi_install_notify_handler(ACPI_HANDLE(&device->dev), ACPI_DEVICE_NOTIFY,
sar_notify, (void *)device) != AE_OK) {
dev_err(&device->dev, "Failed acpi_install_notify_handler\n");
result = -EIO;
goto r_sys;
}
return 0;
r_sys:
sysfs_remove_group(&device->dev.kobj, &intcsar_group);
r_free:
kfree(context);
return result;
}
static void sar_remove(struct platform_device *device)
{
struct wwan_sar_context *context = dev_get_drvdata(&device->dev);
int reg;
acpi_remove_notify_handler(ACPI_HANDLE(&device->dev),
ACPI_DEVICE_NOTIFY, sar_notify);
sysfs_remove_group(&device->dev.kobj, &intcsar_group);
for (reg = 0; reg < MAX_REGULATORY; reg++)
kfree(context->config_data[reg].device_mode_info);
kfree(context);
}
static struct platform_driver sar_driver = {
.probe = sar_probe,
.remove_new = sar_remove,
.driver = {
.name = DRVNAME,
.acpi_match_table = ACPI_PTR(sar_device_ids)
}
};
module_platform_driver(sar_driver);
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("Platform device driver for INTEL MODEM BIOS SAR");
MODULE_AUTHOR("Shravan Sudhakar <[email protected]>");
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