drivers/platform/x86/intel/int1092/intel_sar.c - linux - Git at Google

 // 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 <s.shravan@intel.com>");
	// 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 <s.shravan@intel.com>");