new file mode 100644
@@ -0,0 +1,21 @@
+What: /sys/devices/platform/<platform>/tokens/*
+Date: November 2017
+KernelVersion: 4.15
+Contact: "Mario Limonciello" <mario.limonciello@dell.com>
+Description:
+ A read-only description of Dell platform tokens
+ available on the machine.
+
+ Each token attribute is available as a pair of
+ sysfs attributes readable by a process with
+ CAP_SYS_ADMIN.
+
+ For example the token ID "5" would be available
+ as the following attributes:
+
+ 0005_location
+ 0005_value
+
+ Tokens will vary from machine to machine, and
+ only tokens available on that machine will be
+ displayed.
@@ -3978,6 +3978,13 @@ M: "Maciej W. Rozycki" <macro@linux-mips.org>
S: Maintained
F: drivers/net/fddi/defxx.*
+DELL SMBIOS DRIVER
+M: Pali Rohár <pali.rohar@gmail.com>
+M: Mario Limonciello <mario.limonciello@dell.com>
+L: platform-driver-x86@vger.kernel.org
+S: Maintained
+F: drivers/platform/x86/dell-smbios.*
+
DELL LAPTOP DRIVER
M: Matthew Garrett <mjg59@srcf.ucam.org>
M: Pali Rohár <pali.rohar@gmail.com>
@@ -16,10 +16,12 @@
#include <linux/kernel.h>
#include <linux/module.h>
+#include <linux/capability.h>
#include <linux/dmi.h>
#include <linux/err.h>
#include <linux/gfp.h>
#include <linux/mutex.h>
+#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/io.h>
#include "../../firmware/dcdbas.h"
@@ -39,7 +41,11 @@ static DEFINE_MUTEX(buffer_mutex);
static int da_command_address;
static int da_command_code;
static int da_num_tokens;
+static struct platform_device *platform_device;
static struct calling_interface_token *da_tokens;
+static struct device_attribute *token_location_attrs;
+static struct device_attribute *token_value_attrs;
+static struct attribute **token_attrs;
int dell_smbios_error(int value)
{
@@ -157,6 +163,26 @@ static void __init parse_da_table(const struct dmi_header *dm)
da_num_tokens += tokens;
}
+static void zero_duplicates(struct device *dev)
+{
+ int i, j;
+
+ for (i = 0; i < da_num_tokens; i++) {
+ for (j = i+1; j < da_num_tokens; j++) {
+ if (da_tokens[i].tokenID == 0 ||
+ da_tokens[j].tokenID == 0)
+ continue;
+ if (da_tokens[i].tokenID == da_tokens[j].tokenID) {
+ dev_dbg(dev, "Zeroing dup token ID %x(%x/%x)\n",
+ da_tokens[j].tokenID,
+ da_tokens[j].location,
+ da_tokens[j].value);
+ da_tokens[j].tokenID = 0;
+ }
+ }
+ }
+}
+
static void __init find_tokens(const struct dmi_header *dm, void *dummy)
{
switch (dm->type) {
@@ -170,6 +196,154 @@ static void __init find_tokens(const struct dmi_header *dm, void *dummy)
}
}
+static int match_attribute(struct device *dev,
+ struct device_attribute *attr)
+{
+ int i;
+
+ for (i = 0; i < da_num_tokens * 2; i++) {
+ if (!token_attrs[i])
+ continue;
+ if (strcmp(token_attrs[i]->name, attr->attr.name) == 0)
+ return i/2;
+ }
+ dev_dbg(dev, "couldn't match: %s\n", attr->attr.name);
+ return -EINVAL;
+}
+
+static ssize_t location_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ int i;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ i = match_attribute(dev, attr);
+ if (i > 0)
+ return scnprintf(buf, PAGE_SIZE, "%08x", da_tokens[i].location);
+ return 0;
+}
+
+static ssize_t value_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ int i;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ i = match_attribute(dev, attr);
+ if (i > 0)
+ return scnprintf(buf, PAGE_SIZE, "%08x", da_tokens[i].value);
+ return 0;
+}
+
+static struct attribute_group smbios_attribute_group = {
+ .name = "tokens"
+};
+
+static struct platform_driver platform_driver = {
+ .driver = {
+ .name = "dell-smbios",
+ },
+};
+
+static int build_tokens_sysfs(struct platform_device *dev)
+{
+ char buffer_location[13];
+ char buffer_value[10];
+ char *location_name;
+ char *value_name;
+ size_t size;
+ int ret;
+ int i, j;
+
+ /* (number of tokens + 1 for null terminated */
+ size = sizeof(struct device_attribute) * (da_num_tokens + 1);
+ token_location_attrs = kzalloc(size, GFP_KERNEL);
+ if (!token_location_attrs)
+ return -ENOMEM;
+ token_value_attrs = kzalloc(size, GFP_KERNEL);
+ if (!token_value_attrs)
+ goto out_allocate_value;
+
+ /* need to store both location and value + terminator*/
+ size = sizeof(struct attribute *) * ((2 * da_num_tokens) + 1);
+ token_attrs = kzalloc(size, GFP_KERNEL);
+ if (!token_attrs)
+ goto out_allocate_attrs;
+
+ for (i = 0, j = 0; i < da_num_tokens; i++) {
+ /* skip empty */
+ if (da_tokens[i].tokenID == 0)
+ continue;
+ /* add location */
+ sprintf(buffer_location, "%04x_location",
+ da_tokens[i].tokenID);
+ location_name = kstrdup(buffer_location, GFP_KERNEL);
+ if (location_name == NULL)
+ goto out_unwind_strings;
+ sysfs_attr_init(&token_location_attrs[i].attr);
+ token_location_attrs[i].attr.name = location_name;
+ token_location_attrs[i].attr.mode = 0444;
+ token_location_attrs[i].show = location_show;
+ token_attrs[j++] = &token_location_attrs[i].attr;
+
+ /* add value */
+ sprintf(buffer_value, "%04x_value",
+ da_tokens[i].tokenID);
+ value_name = kstrdup(buffer_value, GFP_KERNEL);
+ if (value_name == NULL)
+ goto loop_fail_create_value;
+ sysfs_attr_init(&token_value_attrs[i].attr);
+ token_value_attrs[i].attr.name = value_name;
+ token_value_attrs[i].attr.mode = 0444;
+ token_value_attrs[i].show = value_show;
+ token_attrs[j++] = &token_value_attrs[i].attr;
+ continue;
+
+loop_fail_create_value:
+ kfree(value_name);
+ goto out_unwind_strings;
+ }
+ smbios_attribute_group.attrs = token_attrs;
+
+ ret = sysfs_create_group(&dev->dev.kobj, &smbios_attribute_group);
+ if (ret)
+ goto out_unwind_strings;
+ return 0;
+
+out_unwind_strings:
+ for (i = i-1; i > 0; i--) {
+ kfree(token_location_attrs[i].attr.name);
+ kfree(token_value_attrs[i].attr.name);
+ }
+ kfree(token_attrs);
+out_allocate_attrs:
+ kfree(token_value_attrs);
+out_allocate_value:
+ kfree(token_location_attrs);
+
+ return -ENOMEM;
+}
+
+static void free_group(struct platform_device *pdev)
+{
+ int i;
+
+ sysfs_remove_group(&pdev->dev.kobj,
+ &smbios_attribute_group);
+ for (i = 0; i < da_num_tokens; i++) {
+ kfree(token_location_attrs[i].attr.name);
+ kfree(token_value_attrs[i].attr.name);
+ }
+ kfree(token_attrs);
+ kfree(token_value_attrs);
+ kfree(token_location_attrs);
+}
+
+
static int __init dell_smbios_init(void)
{
const struct dmi_device *valid;
@@ -197,9 +371,40 @@ static int __init dell_smbios_init(void)
ret = -ENOMEM;
goto fail_buffer;
}
+ ret = platform_driver_register(&platform_driver);
+ if (ret)
+ goto fail_platform_driver;
+
+ platform_device = platform_device_alloc("dell-smbios", 0);
+ if (!platform_device) {
+ ret = -ENOMEM;
+ goto fail_platform_device_alloc;
+ }
+ ret = platform_device_add(platform_device);
+ if (ret)
+ goto fail_platform_device_add;
+
+ /* duplicate tokens will cause problems building sysfs files */
+ zero_duplicates(&platform_device->dev);
+
+ ret = build_tokens_sysfs(platform_device);
+ if (ret)
+ goto fail_create_group;
return 0;
+fail_create_group:
+ platform_device_del(platform_device);
+
+fail_platform_device_add:
+ platform_device_put(platform_device);
+
+fail_platform_device_alloc:
+ platform_driver_unregister(&platform_driver);
+
+fail_platform_driver:
+ free_page((unsigned long)buffer);
+
fail_buffer:
kfree(da_tokens);
return ret;
@@ -207,8 +412,13 @@ static int __init dell_smbios_init(void)
static void __exit dell_smbios_exit(void)
{
- kfree(da_tokens);
+ if (platform_device) {
+ free_group(platform_device);
+ platform_device_unregister(platform_device);
+ platform_driver_unregister(&platform_driver);
+ }
free_page((unsigned long)buffer);
+ kfree(da_tokens);
}
subsys_initcall(dell_smbios_init);