diff options
| -rw-r--r-- | Documentation/ABI/testing/sysfs-platform-dell-smbios | 21 | ||||
| -rw-r--r-- | MAINTAINERS | 7 | ||||
| -rw-r--r-- | drivers/platform/x86/dell-smbios.c | 213 |
3 files changed, 240 insertions, 1 deletions
diff --git a/Documentation/ABI/testing/sysfs-platform-dell-smbios b/Documentation/ABI/testing/sysfs-platform-dell-smbios new file mode 100644 index 000000000000..205d3b6361e0 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-platform-dell-smbios @@ -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. diff --git a/MAINTAINERS b/MAINTAINERS index 69a81400cc65..cb4bc87874c0 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -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> diff --git a/drivers/platform/x86/dell-smbios.c b/drivers/platform/x86/dell-smbios.c index 12a3eb153911..ed4995fdcd46 100644 --- a/drivers/platform/x86/dell-smbios.c +++ b/drivers/platform/x86/dell-smbios.c @@ -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 +163,27 @@ 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++) { + if (da_tokens[i].tokenID == 0) + continue; + for (j = i+1; j < da_num_tokens; j++) { + if (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 +197,154 @@ 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 +372,40 @@ 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 +413,13 @@ fail_buffer: 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); |