linux-headers/linux/rfkill.h
2023-06-07 11:35:51 +00:00

192 lines
6.5 KiB
C

/*
* Copyright (C) 2006 - 2007 Ivo van Doorn
* Copyright (C) 2007 Dmitry Torokhov
* Copyright 2009 Johannes Berg <johannes@sipsolutions.net>
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#ifndef __RFKILL_H
#define __RFKILL_H
#include <linux/types.h>
/* define userspace visible states */
#define RFKILL_STATE_SOFT_BLOCKED 0
#define RFKILL_STATE_UNBLOCKED 1
#define RFKILL_STATE_HARD_BLOCKED 2
/**
* enum rfkill_type - type of rfkill switch.
*
* @RFKILL_TYPE_ALL: toggles all switches (requests only - not a switch type)
* @RFKILL_TYPE_WLAN: switch is on a 802.11 wireless network device.
* @RFKILL_TYPE_BLUETOOTH: switch is on a bluetooth device.
* @RFKILL_TYPE_UWB: switch is on a ultra wideband device.
* @RFKILL_TYPE_WIMAX: switch is on a WiMAX device.
* @RFKILL_TYPE_WWAN: switch is on a wireless WAN device.
* @RFKILL_TYPE_GPS: switch is on a GPS device.
* @RFKILL_TYPE_FM: switch is on a FM radio device.
* @RFKILL_TYPE_NFC: switch is on an NFC device.
* @NUM_RFKILL_TYPES: number of defined rfkill types
*/
enum rfkill_type {
RFKILL_TYPE_ALL = 0,
RFKILL_TYPE_WLAN,
RFKILL_TYPE_BLUETOOTH,
RFKILL_TYPE_UWB,
RFKILL_TYPE_WIMAX,
RFKILL_TYPE_WWAN,
RFKILL_TYPE_GPS,
RFKILL_TYPE_FM,
RFKILL_TYPE_NFC,
NUM_RFKILL_TYPES,
};
/**
* enum rfkill_operation - operation types
* @RFKILL_OP_ADD: a device was added
* @RFKILL_OP_DEL: a device was removed
* @RFKILL_OP_CHANGE: a device's state changed -- userspace changes one device
* @RFKILL_OP_CHANGE_ALL: userspace changes all devices (of a type, or all)
* into a state, also updating the default state used for devices that
* are hot-plugged later.
*/
enum rfkill_operation {
RFKILL_OP_ADD = 0,
RFKILL_OP_DEL,
RFKILL_OP_CHANGE,
RFKILL_OP_CHANGE_ALL,
};
/**
* enum rfkill_hard_block_reasons - hard block reasons
* @RFKILL_HARD_BLOCK_SIGNAL: the hardware rfkill signal is active
* @RFKILL_HARD_BLOCK_NOT_OWNER: the NIC is not owned by the host
*/
enum rfkill_hard_block_reasons {
RFKILL_HARD_BLOCK_SIGNAL = 1 << 0,
RFKILL_HARD_BLOCK_NOT_OWNER = 1 << 1,
};
/**
* struct rfkill_event - events for userspace on /dev/rfkill
* @idx: index of dev rfkill
* @type: type of the rfkill struct
* @op: operation code
* @hard: hard state (0/1)
* @soft: soft state (0/1)
*
* Structure used for userspace communication on /dev/rfkill,
* used for events from the kernel and control to the kernel.
*/
struct rfkill_event {
__u32 idx;
__u8 type;
__u8 op;
__u8 soft;
__u8 hard;
} __attribute__((packed));
/**
* struct rfkill_event_ext - events for userspace on /dev/rfkill
* @idx: index of dev rfkill
* @type: type of the rfkill struct
* @op: operation code
* @hard: hard state (0/1)
* @soft: soft state (0/1)
* @hard_block_reasons: valid if hard is set. One or several reasons from
* &enum rfkill_hard_block_reasons.
*
* Structure used for userspace communication on /dev/rfkill,
* used for events from the kernel and control to the kernel.
*
* See the extensibility docs below.
*/
struct rfkill_event_ext {
__u32 idx;
__u8 type;
__u8 op;
__u8 soft;
__u8 hard;
/*
* older kernels will accept/send only up to this point,
* and if extended further up to any chunk marked below
*/
__u8 hard_block_reasons;
} __attribute__((packed));
/**
* DOC: Extensibility
*
* Originally, we had planned to allow backward and forward compatible
* changes by just adding fields at the end of the structure that are
* then not reported on older kernels on read(), and not written to by
* older kernels on write(), with the kernel reporting the size it did
* accept as the result.
*
* This would have allowed userspace to detect on read() and write()
* which kernel structure version it was dealing with, and if was just
* recompiled it would have gotten the new fields, but obviously not
* accessed them, but things should've continued to work.
*
* Unfortunately, while actually exercising this mechanism to add the
* hard block reasons field, we found that userspace (notably systemd)
* did all kinds of fun things not in line with this scheme:
*
* 1. treat the (expected) short writes as an error;
* 2. ask to read sizeof(struct rfkill_event) but then compare the
* actual return value to RFKILL_EVENT_SIZE_V1 and treat any
* mismatch as an error.
*
* As a consequence, just recompiling with a new struct version caused
* things to no longer work correctly on old and new kernels.
*
* Hence, we've rolled back &struct rfkill_event to the original version
* and added &struct rfkill_event_ext. This effectively reverts to the
* old behaviour for all userspace, unless it explicitly opts in to the
* rules outlined here by using the new &struct rfkill_event_ext.
*
* Additionally, some other userspace (bluez, g-s-d) was reading with a
* large size but as streaming reads rather than message-based, or with
* too strict checks for the returned size. So eventually, we completely
* reverted this, and extended messages need to be opted in to by using
* an ioctl:
*
* ioctl(fd, RFKILL_IOCTL_MAX_SIZE, sizeof(struct rfkill_event_ext));
*
* Userspace using &struct rfkill_event_ext and the ioctl must adhere to
* the following rules:
*
* 1. accept short writes, optionally using them to detect that it's
* running on an older kernel;
* 2. accept short reads, knowing that this means it's running on an
* older kernel;
* 3. treat reads that are as long as requested as acceptable, not
* checking against RFKILL_EVENT_SIZE_V1 or such.
*/
#define RFKILL_EVENT_SIZE_V1 sizeof(struct rfkill_event)
/* ioctl for turning off rfkill-input (if present) */
#define RFKILL_IOC_MAGIC 'R'
#define RFKILL_IOC_NOINPUT 1
#define RFKILL_IOCTL_NOINPUT _IO(RFKILL_IOC_MAGIC, RFKILL_IOC_NOINPUT)
#define RFKILL_IOC_MAX_SIZE 2
#define RFKILL_IOCTL_MAX_SIZE _IOW(RFKILL_IOC_MAGIC, RFKILL_IOC_MAX_SIZE, __u32)
/* and that's all userspace gets */
#endif /* __RFKILL_H */