| // 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; |
| int value; |
| |
| out = acpi_evaluate_dsm(context->handle, &context->guid, rev, |
| COMMAND_ID_DEV_MODE, NULL); |
| if (get_int_value(out, &value)) { |
| 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 = 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(context->handle, &context->guid, rev, |
| COMMAND_ID_CONFIG_TABLE, &req); |
| if (!out) |
| return; |
| if (out->type == ACPI_TYPE_PACKAGE && 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 int 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); |
| return 0; |
| } |
| |
| static struct platform_driver sar_driver = { |
| .probe = sar_probe, |
| .remove = 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 <s.shravan@intel.com>"); |