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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Copyright (c) 2021, Intel Corporation.4 */5 6#include <linux/acpi.h>7#include <linux/kobject.h>8#include <linux/platform_device.h>9#include <linux/sysfs.h>10#include "intel_sar.h"11 12/**13 * get_int_value: Retrieve integer values from ACPI Object14 * @obj: acpi_object pointer which has the integer value15 * @out: output pointer will get integer value16 *17 * Function is used to retrieve integer value from acpi object.18 *19 * Return:20 * * 0 on success21 * * -EIO if there is an issue in acpi_object passed.22 */23static int get_int_value(union acpi_object *obj, int *out)24{25 if (!obj || obj->type != ACPI_TYPE_INTEGER)26 return -EIO;27 *out = (int)obj->integer.value;28 return 0;29}30 31/**32 * update_sar_data: sar data is updated based on regulatory mode33 * @context: pointer to driver context structure34 *35 * sar_data is updated based on regulatory value36 * context->reg_value will never exceed MAX_REGULATORY37 */38static void update_sar_data(struct wwan_sar_context *context)39{40 struct wwan_device_mode_configuration *config =41 &context->config_data[context->reg_value];42 43 if (config->device_mode_info &&44 context->sar_data.device_mode < config->total_dev_mode) {45 int itr = 0;46 47 for (itr = 0; itr < config->total_dev_mode; itr++) {48 if (context->sar_data.device_mode ==49 config->device_mode_info[itr].device_mode) {50 struct wwan_device_mode_info *dev_mode =51 &config->device_mode_info[itr];52 53 context->sar_data.antennatable_index = dev_mode->antennatable_index;54 context->sar_data.bandtable_index = dev_mode->bandtable_index;55 context->sar_data.sartable_index = dev_mode->sartable_index;56 break;57 }58 }59 }60}61 62/**63 * parse_package: parse acpi package for retrieving SAR information64 * @context: pointer to driver context structure65 * @item : acpi_object pointer66 *67 * Given acpi_object is iterated to retrieve information for each device mode.68 * If a given package corresponding to a specific device mode is faulty, it is69 * skipped and the specific entry in context structure will have the default value70 * of zero. Decoding of subsequent device modes is realized by having "continue"71 * statements in the for loop on encountering error in parsing given device mode.72 *73 * Return:74 * AE_OK if success75 * AE_ERROR on error76 */77static acpi_status parse_package(struct wwan_sar_context *context, union acpi_object *item)78{79 struct wwan_device_mode_configuration *data;80 int value, itr, reg;81 union acpi_object *num;82 83 num = &item->package.elements[0];84 if (get_int_value(num, &value) || value < 0 || value >= MAX_REGULATORY)85 return AE_ERROR;86 87 reg = value;88 89 data = &context->config_data[reg];90 if (data->total_dev_mode > MAX_DEV_MODES || data->total_dev_mode == 0 ||91 item->package.count <= data->total_dev_mode)92 return AE_ERROR;93 94 data->device_mode_info = kmalloc_array(data->total_dev_mode,95 sizeof(struct wwan_device_mode_info), GFP_KERNEL);96 if (!data->device_mode_info)97 return AE_ERROR;98 99 for (itr = 0; itr < data->total_dev_mode; itr++) {100 struct wwan_device_mode_info temp = { 0 };101 102 num = &item->package.elements[itr + 1];103 if (num->type != ACPI_TYPE_PACKAGE || num->package.count < TOTAL_DATA)104 continue;105 if (get_int_value(&num->package.elements[0], &temp.device_mode))106 continue;107 if (get_int_value(&num->package.elements[1], &temp.bandtable_index))108 continue;109 if (get_int_value(&num->package.elements[2], &temp.antennatable_index))110 continue;111 if (get_int_value(&num->package.elements[3], &temp.sartable_index))112 continue;113 data->device_mode_info[itr] = temp;114 }115 return AE_OK;116}117 118/**119 * sar_get_device_mode: Extraction of information from BIOS via DSM calls120 * @device: ACPI device for which to retrieve the data121 *122 * Retrieve the current device mode information from the BIOS.123 *124 * Return:125 * AE_OK on success126 * AE_ERROR on error127 */128static acpi_status sar_get_device_mode(struct platform_device *device)129{130 struct wwan_sar_context *context = dev_get_drvdata(&device->dev);131 acpi_status status = AE_OK;132 union acpi_object *out;133 u32 rev = 0;134 135 out = acpi_evaluate_dsm_typed(context->handle, &context->guid, rev,136 COMMAND_ID_DEV_MODE, NULL, ACPI_TYPE_INTEGER);137 if (!out) {138 dev_err(&device->dev, "DSM cmd:%d Failed to retrieve value\n", COMMAND_ID_DEV_MODE);139 status = AE_ERROR;140 goto dev_mode_error;141 }142 context->sar_data.device_mode = out->integer.value;143 update_sar_data(context);144 sysfs_notify(&device->dev.kobj, NULL, SYSFS_DATANAME);145 146dev_mode_error:147 ACPI_FREE(out);148 return status;149}150 151static const struct acpi_device_id sar_device_ids[] = {152 { "INTC1092", 0},153 {}154};155MODULE_DEVICE_TABLE(acpi, sar_device_ids);156 157static ssize_t intc_data_show(struct device *dev, struct device_attribute *attr, char *buf)158{159 struct wwan_sar_context *context = dev_get_drvdata(dev);160 161 return sysfs_emit(buf, "%d %d %d %d\n", context->sar_data.device_mode,162 context->sar_data.bandtable_index,163 context->sar_data.antennatable_index,164 context->sar_data.sartable_index);165}166static DEVICE_ATTR_RO(intc_data);167 168static ssize_t intc_reg_show(struct device *dev, struct device_attribute *attr, char *buf)169{170 struct wwan_sar_context *context = dev_get_drvdata(dev);171 172 return sysfs_emit(buf, "%d\n", context->reg_value);173}174 175static ssize_t intc_reg_store(struct device *dev, struct device_attribute *attr,176 const char *buf, size_t count)177{178 struct wwan_sar_context *context = dev_get_drvdata(dev);179 unsigned int value;180 int read;181 182 if (!count)183 return -EINVAL;184 read = kstrtouint(buf, 10, &value);185 if (read < 0)186 return read;187 if (value >= MAX_REGULATORY)188 return -EOVERFLOW;189 context->reg_value = value;190 update_sar_data(context);191 sysfs_notify(&dev->kobj, NULL, SYSFS_DATANAME);192 return count;193}194static DEVICE_ATTR_RW(intc_reg);195 196static struct attribute *intcsar_attrs[] = {197 &dev_attr_intc_data.attr,198 &dev_attr_intc_reg.attr,199 NULL200};201 202static struct attribute_group intcsar_group = {203 .attrs = intcsar_attrs,204};205 206static void sar_notify(acpi_handle handle, u32 event, void *data)207{208 struct platform_device *device = data;209 210 if (event == SAR_EVENT) {211 if (sar_get_device_mode(device) != AE_OK)212 dev_err(&device->dev, "sar_get_device_mode error");213 }214}215 216static void sar_get_data(int reg, struct wwan_sar_context *context)217{218 union acpi_object *out, req;219 u32 rev = 0;220 221 req.type = ACPI_TYPE_INTEGER;222 req.integer.value = reg;223 out = acpi_evaluate_dsm_typed(context->handle, &context->guid, rev,224 COMMAND_ID_CONFIG_TABLE, &req, ACPI_TYPE_PACKAGE);225 if (!out)226 return;227 if (out->package.count >= 3 &&228 out->package.elements[0].type == ACPI_TYPE_INTEGER &&229 out->package.elements[1].type == ACPI_TYPE_INTEGER &&230 out->package.elements[2].type == ACPI_TYPE_PACKAGE &&231 out->package.elements[2].package.count > 0) {232 context->config_data[reg].version = out->package.elements[0].integer.value;233 context->config_data[reg].total_dev_mode =234 out->package.elements[1].integer.value;235 if (context->config_data[reg].total_dev_mode <= 0 ||236 context->config_data[reg].total_dev_mode > MAX_DEV_MODES) {237 ACPI_FREE(out);238 return;239 }240 parse_package(context, &out->package.elements[2]);241 }242 ACPI_FREE(out);243}244 245static int sar_probe(struct platform_device *device)246{247 struct wwan_sar_context *context;248 int reg;249 int result;250 251 context = kzalloc(sizeof(*context), GFP_KERNEL);252 if (!context)253 return -ENOMEM;254 255 context->sar_device = device;256 context->handle = ACPI_HANDLE(&device->dev);257 dev_set_drvdata(&device->dev, context);258 259 result = guid_parse(SAR_DSM_UUID, &context->guid);260 if (result) {261 dev_err(&device->dev, "SAR UUID parse error: %d\n", result);262 goto r_free;263 }264 265 for (reg = 0; reg < MAX_REGULATORY; reg++)266 sar_get_data(reg, context);267 268 if (sar_get_device_mode(device) != AE_OK) {269 dev_err(&device->dev, "Failed to get device mode\n");270 result = -EIO;271 goto r_free;272 }273 274 result = sysfs_create_group(&device->dev.kobj, &intcsar_group);275 if (result) {276 dev_err(&device->dev, "sysfs creation failed\n");277 goto r_free;278 }279 280 if (acpi_install_notify_handler(ACPI_HANDLE(&device->dev), ACPI_DEVICE_NOTIFY,281 sar_notify, (void *)device) != AE_OK) {282 dev_err(&device->dev, "Failed acpi_install_notify_handler\n");283 result = -EIO;284 goto r_sys;285 }286 return 0;287 288r_sys:289 sysfs_remove_group(&device->dev.kobj, &intcsar_group);290r_free:291 kfree(context);292 return result;293}294 295static void sar_remove(struct platform_device *device)296{297 struct wwan_sar_context *context = dev_get_drvdata(&device->dev);298 int reg;299 300 acpi_remove_notify_handler(ACPI_HANDLE(&device->dev),301 ACPI_DEVICE_NOTIFY, sar_notify);302 sysfs_remove_group(&device->dev.kobj, &intcsar_group);303 for (reg = 0; reg < MAX_REGULATORY; reg++)304 kfree(context->config_data[reg].device_mode_info);305 306 kfree(context);307}308 309static struct platform_driver sar_driver = {310 .probe = sar_probe,311 .remove_new = sar_remove,312 .driver = {313 .name = DRVNAME,314 .acpi_match_table = ACPI_PTR(sar_device_ids)315 }316};317module_platform_driver(sar_driver);318 319MODULE_LICENSE("GPL v2");320MODULE_DESCRIPTION("Platform device driver for INTEL MODEM BIOS SAR");321MODULE_AUTHOR("Shravan Sudhakar <s.shravan@intel.com>");322