This application uses the character device /dev/wmi/dell-smbios
to perform SMBIOS communications from userspace.
It offers demonstrations of a few simple tasks:
- Running a class/select command
- Querying a token value
- Activating a token
Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxxx>
Reviewed-by: Edward O'Callaghan <quasisec@xxxxxxxxxx>
---
MAINTAINERS | 1 +
tools/Makefile | 14 +--
tools/wmi/Makefile | 18 ++++
tools/wmi/dell-smbios-example.c | 210 ++++++++++++++++++++++++++++++++++++++++
4 files changed, 237 insertions(+), 6 deletions(-)
create mode 100644 tools/wmi/Makefile
create mode 100644 tools/wmi/dell-smbios-example.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 84afbf8ef7d5..64529a3f6910 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3997,6 +3997,7 @@ M: Mario Limonciello <mario.limonciello@xxxxxxxx>
L: platform-driver-x86@xxxxxxxxxxxxxxx
S: Maintained
F: drivers/platform/x86/dell-smbios-wmi.c
+F: tools/wmi/dell-smbios-example.c
DELL LAPTOP DRIVER
M: Matthew Garrett <mjg59@xxxxxxxxxxxxx>
diff --git a/tools/Makefile b/tools/Makefile
index 9dfede37c8ff..9d2fd2606810 100644
--- a/tools/Makefile
+++ b/tools/Makefile
@@ -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
diff --git a/tools/wmi/Makefile b/tools/wmi/Makefile
new file mode 100644
index 000000000000..e664f1167388
--- /dev/null
+++ b/tools/wmi/Makefile
@@ -0,0 +1,18 @@
+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)
diff --git a/tools/wmi/dell-smbios-example.c b/tools/wmi/dell-smbios-example.c
new file mode 100644
index 000000000000..a5f97647c9c5
--- /dev/null
+++ b/tools/wmi/dell-smbios-example.c
@@ -0,0 +1,210 @@
+/*
+ * Sample application for SMBIOS communication over WMI interface
+ * Performs the following:
+ * - Simple class/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.class, buffer->std.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.class = CLASS_TOKEN_READ;
+ buffer->std.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.class = CLASS_TOKEN_WRITE;
+ buffer->std.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.class = CLASS_FLASH_INTERFACE;
+ buffer->std.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;
+}
--
2.14.1
