Re: [PATCH V6 1/1] platform/x86: BIOS SAR driver for Intel M.2 Modem

[Hans de Goede <hdegoede@redhat.com>]

Hi,

On 7/22/21 11:44 PM, Shravan S wrote:
> Dynamic BIOS SAR driver exposing dynamic SAR information from BIOS
> 
> The Dynamic SAR (Specific Absorption Rate) driver uses ACPI DSM
> (Device Specific Method) to communicate with BIOS and retrieve
> dynamic SAR information and change notifications. The driver uses
> sysfs to expose this data to userspace via read and notify.
> 
> Sysfs interface is documented in detail under:
> Documentation/ABI/testing/sysfs-driver-intc_sar
> 
> Signed-off-by: Shravan S <s.shravan@intel.com>
> ---
> V6 :
> * Corner case fixes for input data handling
> * Read from BIOS before updating SAR data

Various small comments inline, please address these and send a V7.

Also please base your patch on platform-drivers-x86/for-next

This version does not apply cleanly to for-next.

> 
> ---
>  .../ABI/testing/sysfs-driver-intc_sar         |  57 ++++
>  MAINTAINERS                                   |   7 +
>  drivers/platform/x86/intel/Kconfig            |   1 +
>  drivers/platform/x86/intel/Makefile           |   1 +
>  drivers/platform/x86/intel/int1092/Kconfig    |  14 +
>  drivers/platform/x86/intel/int1092/Makefile   |   1 +
>  .../platform/x86/intel/int1092/intel_sar.c    | 319 ++++++++++++++++++
>  .../platform/x86/intel/int1092/intel_sar.h    |  86 +++++
>  8 files changed, 486 insertions(+)
>  create mode 100644 Documentation/ABI/testing/sysfs-driver-intc_sar
>  create mode 100644 drivers/platform/x86/intel/int1092/Kconfig
>  create mode 100644 drivers/platform/x86/intel/int1092/Makefile
>  create mode 100644 drivers/platform/x86/intel/int1092/intel_sar.c
>  create mode 100644 drivers/platform/x86/intel/int1092/intel_sar.h
> 
> diff --git a/Documentation/ABI/testing/sysfs-driver-intc_sar b/Documentation/ABI/testing/sysfs-driver-intc_sar
> new file mode 100644
> index 000000000000..111bc33975ec
> --- /dev/null
> +++ b/Documentation/ABI/testing/sysfs-driver-intc_sar
> @@ -0,0 +1,57 @@
> +What:		/sys/bus/platform/devices/INTC1092:00/intc_reg
> +Date:		August 2021
> +KernelVersion:	5.13.8

This will end up in 5.15 (if you send V7 soon), not 5.13.8 .

> +Contact:	Shravan S <s.shravan@intel.com>,
> +		An Sudhakar <sudhakar.an@intel.com>
> +Description:
> +		Specific Absorption Rate (SAR) regulatory mode is typically
> +		derived based on information like mcc (Mobile Country Code) and
> +		mnc (Mobile Network Code) that is available for the currently 

This line ends with a space, please drop this (and also in various other
places in this file).

> +		attached LTE network. A userspace application is required to set
> +		the current SAR regulatory mode on the Dynamic SAR driver using
> +		this sysfs node. Such an application can also read back using
> +		this sysfs node, the currently configured regulatory mode value
> +		from the Dynamic SAR driver.
> +
> +		Acceptable regulatory modes are:
> +			==	====
> +			0	FCC
> +			1	CE
> +			2	ISED
> +			==	====
> +
> +		- The regulatory mode value has one of the above values. 
> +		- The default regulatory mode used in the driver is 0.
> +
> +What:		/sys/bus/platform/devices/INTC1092:00/intc_data
> +Date:		August 2021
> +KernelVersion:	5.13.8

This will end up in 5.15 (if you send V7 soon), not 5.13.8 .

> +Contact:	Shravan S <s.shravan@intel.com>,
> +		An Sudhakar <sudhakar.an@intel.com>
> +Description:
> +		This sysfs entry is used to retrieve Dynamic SAR information 
> +		emitted/maintained by a BIOS that supports Dynamic SAR.
> +
> +		The retrieved information is in the order given below:
> +		- device_mode
> +		- bandtable_index
> +		- antennatable_index
> +		- sartable_index
> +		

This empty line contains 2 tabs, please drop them.

> +		The above information is sent as integer values separated
> +		by a single space. This information can then be pushed to a
> +		WWAN modem that uses this to control the transmit signal
> +		level using the Band/Antenna/SAR table index information.
> +		These parameters are derived/decided by aggregating
> +		device-mode like laptop/tablet/clamshell etc. and the
> +		proximity-sensor data available to the embedded controller on
> +		given host. The regulatory mode configured on Dynamic SAR
> +		driver also influences these values.
> +		

2 tabs again.

> +		The above information is communicated to a userspace
> +		application using EPOLLPRI event on file-descriptor (fd)
> +		obtained by opening this sysfs entry. This event is received
> +		using the epoll() system call with EPOLLET flag to get only
> +		edge triggered events. On getting such an event, application
> +		can then read this information from the sysfs node and
> +		consume the given information.

POLLPRI events are only raised once by (e)poll, so combining them with
EPOLLET is not necessary, EPOLLET has no influence on them. I suggest
you replace this entire paragraph with:

                Userspace applications can poll for changes to this file
                using POLLPRI.

> diff --git a/MAINTAINERS b/MAINTAINERS
> index fd25e4ecf0b9..94caff5496d4 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -9221,6 +9221,13 @@ L:	platform-driver-x86@vger.kernel.org
>  S:	Maintained
>  F:	drivers/platform/x86/intel_atomisp2_led.c
>  
> +INTEL BIOS SAR INT1092 DRIVER
> +M:	Shravan S <s.shravan@intel.com>
> +M:	Intel Corporation <linuxwwan@intel.com>
> +L:	platform-driver-x86@vger.kernel.org
> +S:	Maintained
> +F:	drivers/platform/x86/intel/int1092/
> +
>  INTEL BROXTON PMC DRIVER
>  M:	Mika Westerberg <mika.westerberg@linux.intel.com>
>  M:	Zha Qipeng <qipeng.zha@intel.com>
> diff --git a/drivers/platform/x86/intel/Kconfig b/drivers/platform/x86/intel/Kconfig
> index f2eef337eb98..9ff91068becd 100644
> --- a/drivers/platform/x86/intel/Kconfig
> +++ b/drivers/platform/x86/intel/Kconfig
> @@ -18,5 +18,6 @@ if X86_PLATFORM_DRIVERS_INTEL
>  
>  source "drivers/platform/x86/intel/int33fe/Kconfig"
>  source "drivers/platform/x86/intel/int3472/Kconfig"
> +source "drivers/platform/x86/intel/int1092/Kconfig"

Please sort this by name, IOW put this above the other 2 lines.
>  
>  endif # X86_PLATFORM_DRIVERS_INTEL
> diff --git a/drivers/platform/x86/intel/Makefile b/drivers/platform/x86/intel/Makefile
> index 0653055942d5..c0f342316d8f 100644
> --- a/drivers/platform/x86/intel/Makefile
> +++ b/drivers/platform/x86/intel/Makefile
> @@ -6,3 +6,4 @@
>  
>  obj-$(CONFIG_INTEL_CHT_INT33FE)		+= int33fe/
>  obj-$(CONFIG_INTEL_SKL_INT3472)		+= int3472/
> +obj-$(CONFIG_INTEL_SAR_INT1092)		+= int1092/

Please sort this by name, IOW put this above the other 2 lines.

> diff --git a/drivers/platform/x86/intel/int1092/Kconfig b/drivers/platform/x86/intel/int1092/Kconfig
> new file mode 100644
> index 000000000000..2e9a177241aa
> --- /dev/null
> +++ b/drivers/platform/x86/intel/int1092/Kconfig
> @@ -0,0 +1,14 @@
> +config INTEL_SAR_INT1092
> +	tristate "Intel Specific Absorption Rate Driver"
> +	depends on ACPI
> +	help
> +	  This driver helps to limit the exposure of human body to RF frequency by
> +	  providing information to userspace application that will inform the Intel
> +	  M.2 modem to regulate the RF power based on SAR data obtained from the
> +	  sensors captured in the BIOS. ACPI interface exposes this data from the BIOS
> +	  to SAR driver. The front end application in userspace will interact with SAR
> +	  driver to obtain information like the device mode, Antenna index, baseband index,
> +	  SAR table index and use available communication like MBIM interface to enable
> +	  data communication to modem for RF power regulation. Enable this config when
> +	  given platform needs to support "Dynamic SAR" configuration for a modem available
> +	  on the platform.
> diff --git a/drivers/platform/x86/intel/int1092/Makefile b/drivers/platform/x86/intel/int1092/Makefile
> new file mode 100644
> index 000000000000..4ab94e541de3
> --- /dev/null
> +++ b/drivers/platform/x86/intel/int1092/Makefile
> @@ -0,0 +1 @@
> +obj-$(CONFIG_INTEL_SAR_INT1092)		+= intel_sar.o
> diff --git a/drivers/platform/x86/intel/int1092/intel_sar.c b/drivers/platform/x86/intel/int1092/intel_sar.c
> new file mode 100644
> index 000000000000..49f33800681d
> --- /dev/null
> +++ b/drivers/platform/x86/intel/int1092/intel_sar.c
> @@ -0,0 +1,319 @@
> +// 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) {
> +		struct wwan_device_mode_info *dev_mode =
> +			&config->device_mode_info[context->sar_data.device_mode];
> +
> +		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;
> +	}
> +}
> +
> +/**
> + * 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, count;
> +	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)
> +		return AE_ERROR;
> +	count = (data->total_dev_mode < item->package.count) ?
> +			 data->total_dev_mode : item->package.count;

The for below uses "itr + 1", so the last part should be " : (item->package.count - 1)
but since this is an error anyways, why not just replace this with:

	if (item->package.count <= data->total_dev_mode)
		return AE_ERROR;

And get rid of the count variable all together, instead testing
for "itr < data->total_dev_mode" in the for(;;) below ?

> +	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 < count; 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;
> +	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 -EFAULT;

As I mentioned EFAULT should never be used accept on copy from/to user
errors. Use -EINVAL here.

> +	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, *item, req;
> +	acpi_status status = AE_OK;
> +	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].type == ACPI_TYPE_PACKAGE &&
	    out->package.elements[2].package.count > 0) {

Would be better? Then you can drop the item->package.count check below
as well as dropping the "item" local helper variable.

> +		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;
> +		}

These 5 lines:
> +		item = &out->package.elements[2];
> +		if (item->package.count > 0)
> +			status = parse_package(context, item);
> +		else
> +			status = AE_ERROR;

Could then be replaced by:

		parse_package(context, &out->package.elements[2]);

And these 4 lines:
		

> +		if (status != AE_OK) {
> +			ACPI_FREE(out);
> +			return;
> +		}

Can be dropped, since the ACPI_FREE will be done without them too
(1 line below, this is an if not a for, so just falling through
to the next line has the same result) 

Notice this also gets rid of the need for the status local-variable.

> +	}
> +	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;

Empty line here please.
> +	context->sar_device = device;
> +	dev_set_drvdata(&device->dev, context);

Empty line here please.

> +	result = guid_parse(SAR_DSM_UUID, &context->guid);
> +	if (result) {
> +		dev_err(&device->dev, "SAR UUID parse error: %d\n", result);
> +		goto r_free;
> +	}

Empty line here please.

> +	context->handle = ACPI_HANDLE(&device->dev);

Move this to where you set context->sar_device please.

> +	for (reg = 0; reg < MAX_REGULATORY; reg++)
> +		sar_get_data(reg, context);

Empty line here please.

> +	if (sar_get_device_mode(device) != AE_OK) {
> +		dev_err(&device->dev, "Failed to get device mode\n");
> +		result = -EFAULT;

No EFAULT, use EIO here.

> +		goto r_free;
> +	}

Empty line here please.

> +	update_sar_data(context);

Empty line here please.

> +	result = sysfs_create_group(&device->dev.kobj, &intcsar_group);
> +	if (result) {
> +		dev_err(&device->dev, "sysfs creation failed\n");
> +		goto r_free;
> +	}

Empty line here please.

> +	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 = -EFAULT;

-EIO please

> +		goto r_sys;
> +	}
> +	return 0;
> +
> +r_sys:
> +	sysfs_remove_group(&device->dev.kobj, &intcsar_group);
> +r_free:
> +	kfree(context);
> +	dev_set_drvdata(&device->dev, NULL);

dev_set_drvdata( NULL) will be done by the core on probe-failure,
please drop this line.

> +	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);
> +		context->config_data[reg].device_mode_info = NULL;

You are freeing the entire context right after this, so no need
for this device_mode_info = NULL, drop this line please. After
which you can also drop the {}

> +	}

Empty line here please.

> +	kfree(context);
> +	return 0;
> +}
> +
> +static struct platform_driver sar_driver = {
> +	.probe = sar_probe,
> +	.remove = sar_remove,
> +	.driver = {
> +			.name = DRVNAME,
> +			.owner = THIS_MODULE,
> +			.acpi_match_table = ACPI_PTR(sar_device_ids)
> +			}

Wrong indentation of the '}' here.

> +};
> +module_platform_driver(sar_driver);
> +
> +MODULE_LICENSE("GPL v2");
> +MODULE_DESCRIPTION("Platform device driver for INTEL MODEM BIOS SAR");
> +MODULE_AUTHOR("Shravan S <s.shravan@intel.com>");
> diff --git a/drivers/platform/x86/intel/int1092/intel_sar.h b/drivers/platform/x86/intel/int1092/intel_sar.h
> new file mode 100644
> index 000000000000..dfadb243ecb3
> --- /dev/null
> +++ b/drivers/platform/x86/intel/int1092/intel_sar.h
> @@ -0,0 +1,86 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +/*
> + * Copyright (c) 2021, Intel Corporation.
> + */
> +#ifndef INTEL_SAR_H
> +#define INTEL_SAR_H
> +
> +#define COMMAND_ID_DEV_MODE 1
> +#define COMMAND_ID_CONFIG_TABLE 2
> +#define DRVNAME "intc_sar"
> +#define MAX_DEV_MODES 50
> +#define MAX_REGULATORY 3
> +#define SAR_DSM_UUID "82737E72-3A33-4C45-A9C7-57C0411A5F13"
> +#define SAR_EVENT 0x80
> +#define SYSFS_DATANAME "intc_data"
> +#define TOTAL_DATA 4
> +
> +/**
> + * Structure wwan_device_mode_info - device mode information
> + * Holds the data that needs to be passed to userspace.
> + * The data is updated from the BIOS sensor information.
> + * @device_mode: Specific mode of the device
> + * @bandtable_index: Index of RF band
> + * @antennatable_index: Index of antenna
> + * @sartable_index: Index of SAR
> + */
> +struct wwan_device_mode_info {
> +		int device_mode;
> +		int bandtable_index;
> +		int antennatable_index;
> +		int sartable_index;

Please replace these 2 tab indents with 1 tab idents, this goes
for the entire .h file.

> +};
> +
> +/**
> + * Structure wwan_device_mode_configuration - device configuration
> + * Holds the data that is configured and obtained on probe event.
> + * The data is updated from the BIOS sensor information.
> + * @version: Mode configuration version
> + * @total_dev_mode: Total number of device modes
> + * @device_mode_info: pointer to structure wwan_device_mode_info
> + */
> +struct wwan_device_mode_configuration {
> +		int version;
> +		int total_dev_mode;
> +		struct wwan_device_mode_info *device_mode_info;
> +};
> +
> +/**
> + * Structure wwan_supported_info - userspace datastore
> + * Holds the data that is obtained from userspace
> + * The data is updated from the userspace and send value back in the
> + * structure format that is mentioned here.
> + * @reg_mode_needed: regulatory mode set by user for tests
> + * @bios_table_revision: Version of SAR table
> + * @num_supported_modes: Total supported modes based on reg_mode
> + */
> +struct wwan_supported_info {
> +		int reg_mode_needed;
> +		int bios_table_revision;
> +		int num_supported_modes;
> +};
> +
> +/**
> + * Structure wwan_sar_context - context of SAR
> + * Holds the complete context as long as the driver is in existence
> + * The context holds instance of the data used for different cases.
> + * @guid: Group id
> + * @handle: store acpi handle
> + * @reg_value: regulatory value
> + * Regulatory 0: FCC, 1: CE, 2: ISED
> + * @sar_device: platform_device type
> + * @sar_kobject: kobject for sysfs
> + * @supported_data: wwan_supported_info struct
> + * @sar_data: wwan_device_mode_info struct
> + * @config_data: wwan_device_mode_configuration array struct
> + */
> +struct wwan_sar_context {
> +		guid_t guid;
> +		acpi_handle handle;
> +		int reg_value;
> +		struct platform_device *sar_device;
> +		struct wwan_supported_info supported_data;
> +		struct wwan_device_mode_info sar_data;
> +		struct wwan_device_mode_configuration config_data[MAX_REGULATORY];
> +};
> +#endif /* INTEL_SAR_H */
> 

Regards,

Hans