diff options
| -rw-r--r-- | Documentation/ABI/testing/dell-smbios-wmi | 41 | ||||
| -rw-r--r-- | drivers/platform/x86/dell-smbios-wmi.c | 54 | ||||
| -rw-r--r-- | drivers/platform/x86/dell-smbios.h | 32 | ||||
| -rw-r--r-- | include/uapi/linux/wmi.h | 47 |
4 files changed, 133 insertions, 41 deletions
diff --git a/Documentation/ABI/testing/dell-smbios-wmi b/Documentation/ABI/testing/dell-smbios-wmi new file mode 100644 index 000000000000..fc919ce16008 --- /dev/null +++ b/Documentation/ABI/testing/dell-smbios-wmi @@ -0,0 +1,41 @@ +What: /dev/wmi/dell-smbios +Date: November 2017 +KernelVersion: 4.15 +Contact: "Mario Limonciello" <mario.limonciello@dell.com> +Description: + Perform SMBIOS calls on supported Dell machines. + through the Dell ACPI-WMI interface. + + IOCTL's and buffer formats are defined in: + <uapi/linux/wmi.h> + + 1) To perform an SMBIOS call from userspace, you'll need to + first determine the minimum size of the calling interface + buffer for your machine. + Platforms that contain larger buffers can return larger + objects from the system firmware. + Commonly this size is either 4k or 32k. + + To determine the size of the buffer read() a u64 dword from + the WMI character device /dev/wmi/dell-smbios. + + 2) After you've determined the minimum size of the calling + interface buffer, you can allocate a structure that represents + the structure documented above. + + 3) In the 'length' object store the size of the buffer you + determined above and allocated. + + 4) In this buffer object, prepare as necessary for the SMBIOS + call you're interested in. Typically SMBIOS buffers have + "class", "select", and "input" defined to values that coincide + with the data you are interested in. + Documenting class/select/input values is outside of the scope + of this documentation. Check with the libsmbios project for + further documentation on these values. + + 6) Run the call by using ioctl() as described in the header. + + 7) The output will be returned in the buffer object. + + 8) Be sure to free up your allocated object. diff --git a/drivers/platform/x86/dell-smbios-wmi.c b/drivers/platform/x86/dell-smbios-wmi.c index b31f457e58c3..35c13815b24c 100644 --- a/drivers/platform/x86/dell-smbios-wmi.c +++ b/drivers/platform/x86/dell-smbios-wmi.c @@ -30,17 +30,6 @@ struct misc_bios_flags_structure { #define DELL_WMI_SMBIOS_GUID "A80593CE-A997-11DA-B012-B622A1EF5492" -struct dell_wmi_extensions { - __u32 argattrib; - __u32 blength; - __u8 data[]; -} __packed; - -struct dell_wmi_smbios_buffer { - struct calling_interface_buffer std; - struct dell_wmi_extensions ext; -} __packed; - struct wmi_smbios_priv { struct dell_wmi_smbios_buffer *buf; struct list_head list; @@ -117,6 +106,42 @@ int dell_smbios_wmi_call(struct calling_interface_buffer *buffer) return ret; } +static long dell_smbios_wmi_filter(struct wmi_device *wdev, unsigned int cmd, + struct wmi_ioctl_buffer *arg) +{ + struct wmi_smbios_priv *priv; + int ret = 0; + + switch (cmd) { + case DELL_WMI_SMBIOS_CMD: + mutex_lock(&call_mutex); + priv = dev_get_drvdata(&wdev->dev); + if (!priv) { + ret = -ENODEV; + goto fail_smbios_cmd; + } + memcpy(priv->buf, arg, priv->req_buf_size); + if (dell_smbios_call_filter(&wdev->dev, &priv->buf->std)) { + dev_err(&wdev->dev, "Invalid call %d/%d:%8x\n", + priv->buf->std.cmd_class, + priv->buf->std.cmd_select, + priv->buf->std.input[0]); + ret = -EFAULT; + goto fail_smbios_cmd; + } + ret = run_smbios_call(priv->wdev); + if (ret) + goto fail_smbios_cmd; + memcpy(arg, priv->buf, priv->req_buf_size); +fail_smbios_cmd: + mutex_unlock(&call_mutex); + break; + default: + ret = -ENOIOCTLCMD; + } + return ret; +} + static int dell_smbios_wmi_probe(struct wmi_device *wdev) { struct wmi_smbios_priv *priv; @@ -135,6 +160,12 @@ static int dell_smbios_wmi_probe(struct wmi_device *wdev) if (!dell_wmi_get_size(&priv->req_buf_size)) return -EPROBE_DEFER; + /* add in the length object we will use internally with ioctl */ + priv->req_buf_size += sizeof(u64); + ret = set_required_buffer_size(wdev, priv->req_buf_size); + if (ret) + return ret; + count = get_order(priv->req_buf_size); priv->buf = (void *)__get_free_pages(GFP_KERNEL, count); if (!priv->buf) @@ -210,6 +241,7 @@ static struct wmi_driver dell_smbios_wmi_driver = { .probe = dell_smbios_wmi_probe, .remove = dell_smbios_wmi_remove, .id_table = dell_smbios_wmi_id_table, + .filter_callback = dell_smbios_wmi_filter, }; static int __init init_dell_smbios_wmi(void) diff --git a/drivers/platform/x86/dell-smbios.h b/drivers/platform/x86/dell-smbios.h index 91e8004d48ba..138d478d9adc 100644 --- a/drivers/platform/x86/dell-smbios.h +++ b/drivers/platform/x86/dell-smbios.h @@ -17,23 +17,11 @@ #define _DELL_SMBIOS_H_ #include <linux/device.h> +#include <uapi/linux/wmi.h> -/* Classes and selects used in kernel drivers */ -#define CLASS_TOKEN_READ 0 -#define CLASS_TOKEN_WRITE 1 -#define SELECT_TOKEN_STD 0 -#define SELECT_TOKEN_BAT 1 -#define SELECT_TOKEN_AC 2 +/* Classes and selects used only in kernel drivers */ #define CLASS_KBD_BACKLIGHT 4 #define SELECT_KBD_BACKLIGHT 11 -#define CLASS_FLASH_INTERFACE 7 -#define SELECT_FLASH_INTERFACE 3 -#define CLASS_ADMIN_PROP 10 -#define SELECT_ADMIN_PROP 3 -#define CLASS_INFO 17 -#define SELECT_RFKILL 11 -#define SELECT_APP_REGISTRATION 3 -#define SELECT_DOCK 22 /* Tokens used in kernel drivers, any of these * should be filtered from userspace access @@ -50,24 +38,8 @@ #define GLOBAL_MIC_MUTE_ENABLE 0x0364 #define GLOBAL_MIC_MUTE_DISABLE 0x0365 -/* tokens whitelisted to userspace use */ -#define CAPSULE_EN_TOKEN 0x0461 -#define CAPSULE_DIS_TOKEN 0x0462 -#define WSMT_EN_TOKEN 0x04EC -#define WSMT_DIS_TOKEN 0x04ED - struct notifier_block; -/* This structure will be modified by the firmware when we enter - * system management mode, hence the volatiles */ - -struct calling_interface_buffer { - u16 cmd_class; - u16 cmd_select; - volatile u32 input[4]; - volatile u32 output[4]; -} __packed; - struct calling_interface_token { u16 tokenID; u16 location; diff --git a/include/uapi/linux/wmi.h b/include/uapi/linux/wmi.h index 7e52350ac9b3..7a92e9e3d1c0 100644 --- a/include/uapi/linux/wmi.h +++ b/include/uapi/linux/wmi.h @@ -10,6 +10,7 @@ #ifndef _UAPI_LINUX_WMI_H #define _UAPI_LINUX_WMI_H +#include <linux/ioctl.h> #include <linux/types.h> /* WMI bus will filter all WMI vendor driver requests through this IOC */ @@ -23,4 +24,50 @@ struct wmi_ioctl_buffer { __u8 data[]; }; +/* This structure may be modified by the firmware when we enter + * system management mode through SMM, hence the volatiles + */ +struct calling_interface_buffer { + __u16 cmd_class; + __u16 cmd_select; + volatile __u32 input[4]; + volatile __u32 output[4]; +} __packed; + +struct dell_wmi_extensions { + __u32 argattrib; + __u32 blength; + __u8 data[]; +} __packed; + +struct dell_wmi_smbios_buffer { + __u64 length; + struct calling_interface_buffer std; + struct dell_wmi_extensions ext; +} __packed; + +/* Whitelisted smbios class/select commands */ +#define CLASS_TOKEN_READ 0 +#define CLASS_TOKEN_WRITE 1 +#define SELECT_TOKEN_STD 0 +#define SELECT_TOKEN_BAT 1 +#define SELECT_TOKEN_AC 2 +#define CLASS_FLASH_INTERFACE 7 +#define SELECT_FLASH_INTERFACE 3 +#define CLASS_ADMIN_PROP 10 +#define SELECT_ADMIN_PROP 3 +#define CLASS_INFO 17 +#define SELECT_RFKILL 11 +#define SELECT_APP_REGISTRATION 3 +#define SELECT_DOCK 22 + +/* whitelisted tokens */ +#define CAPSULE_EN_TOKEN 0x0461 +#define CAPSULE_DIS_TOKEN 0x0462 +#define WSMT_EN_TOKEN 0x04EC +#define WSMT_DIS_TOKEN 0x04ED + +/* Dell SMBIOS calling IOCTL command used by dell-smbios-wmi */ +#define DELL_WMI_SMBIOS_CMD _IOWR(WMI_IOC, 0, struct dell_wmi_smbios_buffer) + #endif |