tools/wmi: add a sample for dell smbios communication over WMI (9d64fc08) · Commits · e / devices / android_kernel_fairphone_FP5

MAINTAINERS

+1 −0

Original line number	Diff line number	Diff line
		@@ -3997,6 +3997,7 @@ M: Mario Limonciello <mario.limonciello@dell.com>
		L: platform-driver-x86@vger.kernel.org
		S: Maintained
		F: drivers/platform/x86/dell-smbios-wmi.c
		F: tools/wmi/dell-smbios-example.c

		DELL LAPTOP DRIVER
		M: Matthew Garrett <mjg59@srcf.ucam.org>

tools/Makefile

+8 −6

Original line number	Diff line number	Diff line
		@@ -29,6 +29,7 @@ help:
		@echo ' usb - USB testing tools'
		@echo ' virtio - vhost test module'
		@echo ' vm - misc vm tools'
		@echo ' wmi - WMI interface examples'
		@echo ' x86_energy_perf_policy - Intel energy policy tool'
		@echo ''
		@echo 'You can do:'
		@@ -57,7 +58,7 @@ acpi: FORCE
		cpupower: FORCE
		$(call descend,power/$@)

		cgroup firewire hv guest spi usb virtio vm net iio gpio objtool leds: FORCE
		cgroup firewire hv guest spi usb virtio vm net iio gpio objtool leds wmi: FORCE
		$(call descend,$@)

		liblockdep: FORCE
		@@ -92,7 +93,7 @@ kvm_stat: FORCE
		all: acpi cgroup cpupower gpio hv firewire liblockdep \
		perf selftests spi turbostat usb \
		virtio vm net x86_energy_perf_policy \
		tmon freefall iio objtool kvm_stat
		tmon freefall iio objtool kvm_stat wmi

		acpi_install:
		$(call descend,power/$(@:_install=),install)
		@@ -100,7 +101,7 @@ acpi_install:
		cpupower_install:
		$(call descend,power/$(@:_install=),install)

		cgroup_install firewire_install gpio_install hv_install iio_install perf_install spi_install usb_install virtio_install vm_install net_install objtool_install:
		cgroup_install firewire_install gpio_install hv_install iio_install perf_install spi_install usb_install virtio_install vm_install net_install objtool_install wmi_install:
		$(call descend,$(@:_install=),install)

		liblockdep_install:
		@@ -125,7 +126,8 @@ install: acpi_install cgroup_install cpupower_install gpio_install \
		hv_install firewire_install iio_install liblockdep_install \
		perf_install selftests_install turbostat_install usb_install \
		virtio_install vm_install net_install x86_energy_perf_policy_install \
		tmon_install freefall_install objtool_install kvm_stat_install
		tmon_install freefall_install objtool_install kvm_stat_install \
		wmi_install

		acpi_clean:
		$(call descend,power/acpi,clean)
		@@ -133,7 +135,7 @@ acpi_clean:
		cpupower_clean:
		$(call descend,power/cpupower,clean)

		cgroup_clean hv_clean firewire_clean spi_clean usb_clean virtio_clean vm_clean net_clean iio_clean gpio_clean objtool_clean leds_clean:
		cgroup_clean hv_clean firewire_clean spi_clean usb_clean virtio_clean vm_clean wmi_clean net_clean iio_clean gpio_clean objtool_clean leds_clean:
		$(call descend,$(@:_clean=),clean)

		liblockdep_clean:
		@@ -171,6 +173,6 @@ clean: acpi_clean cgroup_clean cpupower_clean hv_clean firewire_clean \
		perf_clean selftests_clean turbostat_clean spi_clean usb_clean virtio_clean \
		vm_clean net_clean iio_clean x86_energy_perf_policy_clean tmon_clean \
		freefall_clean build_clean libbpf_clean libsubcmd_clean liblockdep_clean \
		gpio_clean objtool_clean leds_clean
		gpio_clean objtool_clean leds_clean wmi_clean

		.PHONY: FORCE

tools/wmi/Makefile

0 → 100644

+18 −0

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		PREFIX ?= /usr
		SBINDIR ?= sbin
		INSTALL ?= install
		CFLAGS += -D__EXPORTED_HEADERS__ -I../../include/uapi -I../../include
		CC = $(CROSS_COMPILE)gcc

		TARGET = dell-smbios-example

		all: $(TARGET)

		%: %.c
		$(CC) $(CFLAGS) $(LDFLAGS) -o $@ $<

		clean:
		$(RM) $(TARGET)

		install: dell-smbios-example
		$(INSTALL) -D -m 755 $(TARGET) $(DESTDIR)$(PREFIX)/$(SBINDIR)/$(TARGET)

tools/wmi/dell-smbios-example.c

0 → 100644

+210 −0

Original line number	Diff line number	Diff line
		/*
		* Sample application for SMBIOS communication over WMI interface
		* Performs the following:
		* - Simple cmd_class/cmd_select lookup for TPM information
		* - Simple query of known tokens and their values
		* - Simple activation of a token
		*
		* Copyright (C) 2017 Dell, Inc.
		*
		* This program is free software; you can redistribute it and/or modify
		* it under the terms of the GNU General Public License version 2 as
		* published by the Free Software Foundation.
		*/

		#include <errno.h>
		#include <fcntl.h>
		#include <stdio.h>
		#include <stdlib.h>
		#include <sys/ioctl.h>
		#include <unistd.h>

		/* if uapi header isn't installed, this might not yet exist */
		#ifndef __packed
		#define __packed __attribute__((packed))
		#endif
		#include <linux/wmi.h>

		/* It would be better to discover these using udev, but for a simple
		* application they're hardcoded
		*/
		static const char *ioctl_devfs = "/dev/wmi/dell-smbios";
		static const char *token_sysfs =
		"/sys/bus/platform/devices/dell-smbios.0/tokens";

		static void show_buffer(struct dell_wmi_smbios_buffer *buffer)
		{
		printf("Call: %x/%x [%x,%x,%x,%x]\nResults: [%8x,%8x,%8x,%8x]\n",
		buffer->std.cmd_class, buffer->std.cmd_select,
		buffer->std.input[0], buffer->std.input[1],
		buffer->std.input[2], buffer->std.input[3],
		buffer->std.output[0], buffer->std.output[1],
		buffer->std.output[2], buffer->std.output[3]);
		}

		static int run_wmi_smbios_cmd(struct dell_wmi_smbios_buffer *buffer)
		{
		int fd;
		int ret;

		fd = open(ioctl_devfs, O_NONBLOCK);
		ret = ioctl(fd, DELL_WMI_SMBIOS_CMD, buffer);
		close(fd);
		return ret;
		}

		static int find_token(__u16 token, __u16 location, __u16 value)
		{
		char location_sysfs[60];
		char value_sysfs[57];
		char buf[4096];
		FILE *f;
		int ret;

		ret = sprintf(value_sysfs, "%s/%04x_value", token_sysfs, token);
		if (ret < 0) {
		printf("sprintf value failed\n");
		return 2;
		}
		f = fopen(value_sysfs, "rb");
		if (!f) {
		printf("failed to open %s\n", value_sysfs);
		return 2;
		}
		fread(buf, 1, 4096, f);
		fclose(f);
		*value = (__u16) strtol(buf, NULL, 16);

		ret = sprintf(location_sysfs, "%s/%04x_location", token_sysfs, token);
		if (ret < 0) {
		printf("sprintf location failed\n");
		return 1;
		}
		f = fopen(location_sysfs, "rb");
		if (!f) {
		printf("failed to open %s\n", location_sysfs);
		return 2;
		}
		fread(buf, 1, 4096, f);
		fclose(f);
		*location = (__u16) strtol(buf, NULL, 16);

		if (*location)
		return 0;
		return 2;
		}

		static int token_is_active(__u16 location, __u16 cmpvalue,
		struct dell_wmi_smbios_buffer *buffer)
		{
		int ret;

		buffer->std.cmd_class = CLASS_TOKEN_READ;
		buffer->std.cmd_select = SELECT_TOKEN_STD;
		buffer->std.input[0] = *location;
		ret = run_wmi_smbios_cmd(buffer);
		if (ret != 0 \|\| buffer->std.output[0] != 0)
		return ret;
		ret = (buffer->std.output[1] == *cmpvalue);
		return ret;
		}

		static int query_token(__u16 token, struct dell_wmi_smbios_buffer *buffer)
		{
		__u16 location;
		__u16 value;
		int ret;

		ret = find_token(token, &location, &value);
		if (ret != 0) {
		printf("unable to find token %04x\n", token);
		return 1;
		}
		return token_is_active(&location, &value, buffer);
		}

		static int activate_token(struct dell_wmi_smbios_buffer *buffer,
		__u16 token)
		{
		__u16 location;
		__u16 value;
		int ret;

		ret = find_token(token, &location, &value);
		if (ret != 0) {
		printf("unable to find token %04x\n", token);
		return 1;
		}
		buffer->std.cmd_class = CLASS_TOKEN_WRITE;
		buffer->std.cmd_select = SELECT_TOKEN_STD;
		buffer->std.input[0] = location;
		buffer->std.input[1] = 1;
		ret = run_wmi_smbios_cmd(buffer);
		return ret;
		}

		static int query_buffer_size(__u64 *buffer_size)
		{
		FILE *f;

		f = fopen(ioctl_devfs, "rb");
		if (!f)
		return -EINVAL;
		fread(buffer_size, sizeof(__u64), 1, f);
		fclose(f);
		return EXIT_SUCCESS;
		}

		int main(void)
		{
		struct dell_wmi_smbios_buffer *buffer;
		int ret;
		__u64 value = 0;

		ret = query_buffer_size(&value);
		if (ret == EXIT_FAILURE \|\| !value) {
		printf("Unable to read buffer size\n");
		goto out;
		}
		printf("Detected required buffer size %lld\n", value);

		buffer = malloc(value);
		if (buffer == NULL) {
		printf("failed to alloc memory for ioctl\n");
		ret = -ENOMEM;
		goto out;
		}
		buffer->length = value;

		/* simple SMBIOS call for looking up TPM info */
		buffer->std.cmd_class = CLASS_FLASH_INTERFACE;
		buffer->std.cmd_select = SELECT_FLASH_INTERFACE;
		buffer->std.input[0] = 2;
		ret = run_wmi_smbios_cmd(buffer);
		if (ret) {
		printf("smbios ioctl failed: %d\n", ret);
		ret = EXIT_FAILURE;
		goto out;
		}
		show_buffer(buffer);

		/* query some tokens */
		ret = query_token(CAPSULE_EN_TOKEN, buffer);
		printf("UEFI Capsule enabled token is: %d\n", ret);
		ret = query_token(CAPSULE_DIS_TOKEN, buffer);
		printf("UEFI Capsule disabled token is: %d\n", ret);

		/* activate UEFI capsule token if disabled */
		if (ret) {
		printf("Enabling UEFI capsule token");
		if (activate_token(buffer, CAPSULE_EN_TOKEN)) {
		printf("activate failed\n");
		ret = -1;
		goto out;
		}
		}
		ret = EXIT_SUCCESS;
		out:
		free(buffer);
		return ret;
		}