1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 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 Object 14 * @obj: acpi_object pointer which has the integer value 15 * @out: output pointer will get integer value 16 * 17 * Function is used to retrieve integer value from acpi object. 18 * 19 * Return: 20 * * 0 on success 21 * * -EIO if there is an issue in acpi_object passed. 22 */ 23 static 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 mode 33 * @context: pointer to driver context structure 34 * 35 * sar_data is updated based on regulatory value 36 * context->reg_value will never exceed MAX_REGULATORY 37 */ 38 static 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 information 64 * @context: pointer to driver context structure 65 * @item : acpi_object pointer 66 * 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 is 69 * skipped and the specific entry in context structure will have the default value 70 * 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 success 75 * AE_ERROR on error 76 */ 77 static 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 calls 120 * @device: ACPI device for which to retrieve the data 121 * 122 * Retrieve the current device mode information from the BIOS. 123 * 124 * Return: 125 * AE_OK on success 126 * AE_ERROR on error 127 */ 128 static 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); 145 146 dev_mode_error: 147 ACPI_FREE(out); 148 return status; 149 } 150 151 static const struct acpi_device_id sar_device_ids[] = { 152 { "INTC1092", 0}, 153 {} 154 }; 155 MODULE_DEVICE_TABLE(acpi, sar_device_ids); 156 157 static 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 } 166 static DEVICE_ATTR_RO(intc_data); 167 168 static 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 } 174 175 static 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 } 194 static DEVICE_ATTR_RW(intc_reg); 195 196 static struct attribute *intcsar_attrs[] = { 197 &dev_attr_intc_data.attr, 198 &dev_attr_intc_reg.attr, 199 NULL 200 }; 201 202 static struct attribute_group intcsar_group = { 203 .attrs = intcsar_attrs, 204 }; 205 206 static 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 } 215 216 static 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 } 244 245 static 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; 287 288 r_sys: 289 sysfs_remove_group(&device->dev.kobj, &intcsar_group); 290 r_free: 291 kfree(context); 292 return result; 293 } 294 295 static 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 } 308 309 static 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 }; 317 module_platform_driver(sar_driver); 318 319 MODULE_LICENSE("GPL v2"); 320 MODULE_DESCRIPTION("Platform device driver for INTEL MODEM BIOS SAR"); 321 MODULE_AUTHOR("Shravan Sudhakar <s.shravan@intel.com>"); 322