swh:1:snp:77163734605b0ec556b01d897b7bb4a7e30d46b6
Tip revision: 2dcd0af568b0cf583645c8a317dd12e344b1c72a authored by Linus Torvalds on 15 May 2016, 22:43:13 UTC
Linux 4.6
Linux 4.6
Tip revision: 2dcd0af
op-rfkill.c
/*
* Linux WiMAX
* RF-kill framework integration
*
*
* Copyright (C) 2008 Intel Corporation <linux-wimax@intel.com>
* Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA.
*
*
* This integrates into the Linux Kernel rfkill susbystem so that the
* drivers just have to do the bare minimal work, which is providing a
* method to set the software RF-Kill switch and to report changes in
* the software and hardware switch status.
*
* A non-polled generic rfkill device is embedded into the WiMAX
* subsystem's representation of a device.
*
* FIXME: Need polled support? Let drivers provide a poll routine
* and hand it to rfkill ops then?
*
* All device drivers have to do is after wimax_dev_init(), call
* wimax_report_rfkill_hw() and wimax_report_rfkill_sw() to update
* initial state and then every time it changes. See wimax.h:struct
* wimax_dev for more information.
*
* ROADMAP
*
* wimax_gnl_doit_rfkill() User space calling wimax_rfkill()
* wimax_rfkill() Kernel calling wimax_rfkill()
* __wimax_rf_toggle_radio()
*
* wimax_rfkill_set_radio_block() RF-Kill subsystem calling
* __wimax_rf_toggle_radio()
*
* __wimax_rf_toggle_radio()
* wimax_dev->op_rfkill_sw_toggle() Driver backend
* __wimax_state_change()
*
* wimax_report_rfkill_sw() Driver reports state change
* __wimax_state_change()
*
* wimax_report_rfkill_hw() Driver reports state change
* __wimax_state_change()
*
* wimax_rfkill_add() Initialize/shutdown rfkill support
* wimax_rfkill_rm() [called by wimax_dev_add/rm()]
*/
#include <net/wimax.h>
#include <net/genetlink.h>
#include <linux/wimax.h>
#include <linux/security.h>
#include <linux/rfkill.h>
#include <linux/export.h>
#include "wimax-internal.h"
#define D_SUBMODULE op_rfkill
#include "debug-levels.h"
/**
* wimax_report_rfkill_hw - Reports changes in the hardware RF switch
*
* @wimax_dev: WiMAX device descriptor
*
* @state: New state of the RF Kill switch. %WIMAX_RF_ON radio on,
* %WIMAX_RF_OFF radio off.
*
* When the device detects a change in the state of thehardware RF
* switch, it must call this function to let the WiMAX kernel stack
* know that the state has changed so it can be properly propagated.
*
* The WiMAX stack caches the state (the driver doesn't need to). As
* well, as the change is propagated it will come back as a request to
* change the software state to mirror the hardware state.
*
* If the device doesn't have a hardware kill switch, just report
* it on initialization as always on (%WIMAX_RF_ON, radio on).
*/
void wimax_report_rfkill_hw(struct wimax_dev *wimax_dev,
enum wimax_rf_state state)
{
int result;
struct device *dev = wimax_dev_to_dev(wimax_dev);
enum wimax_st wimax_state;
d_fnstart(3, dev, "(wimax_dev %p state %u)\n", wimax_dev, state);
BUG_ON(state == WIMAX_RF_QUERY);
BUG_ON(state != WIMAX_RF_ON && state != WIMAX_RF_OFF);
mutex_lock(&wimax_dev->mutex);
result = wimax_dev_is_ready(wimax_dev);
if (result < 0)
goto error_not_ready;
if (state != wimax_dev->rf_hw) {
wimax_dev->rf_hw = state;
if (wimax_dev->rf_hw == WIMAX_RF_ON &&
wimax_dev->rf_sw == WIMAX_RF_ON)
wimax_state = WIMAX_ST_READY;
else
wimax_state = WIMAX_ST_RADIO_OFF;
result = rfkill_set_hw_state(wimax_dev->rfkill,
state == WIMAX_RF_OFF);
__wimax_state_change(wimax_dev, wimax_state);
}
error_not_ready:
mutex_unlock(&wimax_dev->mutex);
d_fnend(3, dev, "(wimax_dev %p state %u) = void [%d]\n",
wimax_dev, state, result);
}
EXPORT_SYMBOL_GPL(wimax_report_rfkill_hw);
/**
* wimax_report_rfkill_sw - Reports changes in the software RF switch
*
* @wimax_dev: WiMAX device descriptor
*
* @state: New state of the RF kill switch. %WIMAX_RF_ON radio on,
* %WIMAX_RF_OFF radio off.
*
* Reports changes in the software RF switch state to the WiMAX stack.
*
* The main use is during initialization, so the driver can query the
* device for its current software radio kill switch state and feed it
* to the system.
*
* On the side, the device does not change the software state by
* itself. In practice, this can happen, as the device might decide to
* switch (in software) the radio off for different reasons.
*/
void wimax_report_rfkill_sw(struct wimax_dev *wimax_dev,
enum wimax_rf_state state)
{
int result;
struct device *dev = wimax_dev_to_dev(wimax_dev);
enum wimax_st wimax_state;
d_fnstart(3, dev, "(wimax_dev %p state %u)\n", wimax_dev, state);
BUG_ON(state == WIMAX_RF_QUERY);
BUG_ON(state != WIMAX_RF_ON && state != WIMAX_RF_OFF);
mutex_lock(&wimax_dev->mutex);
result = wimax_dev_is_ready(wimax_dev);
if (result < 0)
goto error_not_ready;
if (state != wimax_dev->rf_sw) {
wimax_dev->rf_sw = state;
if (wimax_dev->rf_hw == WIMAX_RF_ON &&
wimax_dev->rf_sw == WIMAX_RF_ON)
wimax_state = WIMAX_ST_READY;
else
wimax_state = WIMAX_ST_RADIO_OFF;
__wimax_state_change(wimax_dev, wimax_state);
rfkill_set_sw_state(wimax_dev->rfkill, state == WIMAX_RF_OFF);
}
error_not_ready:
mutex_unlock(&wimax_dev->mutex);
d_fnend(3, dev, "(wimax_dev %p state %u) = void [%d]\n",
wimax_dev, state, result);
}
EXPORT_SYMBOL_GPL(wimax_report_rfkill_sw);
/*
* Callback for the RF Kill toggle operation
*
* This function is called by:
*
* - The rfkill subsystem when the RF-Kill key is pressed in the
* hardware and the driver notifies through
* wimax_report_rfkill_hw(). The rfkill subsystem ends up calling back
* here so the software RF Kill switch state is changed to reflect
* the hardware switch state.
*
* - When the user sets the state through sysfs' rfkill/state file
*
* - When the user calls wimax_rfkill().
*
* This call blocks!
*
* WARNING! When we call rfkill_unregister(), this will be called with
* state 0!
*
* WARNING: wimax_dev must be locked
*/
static
int __wimax_rf_toggle_radio(struct wimax_dev *wimax_dev,
enum wimax_rf_state state)
{
int result = 0;
struct device *dev = wimax_dev_to_dev(wimax_dev);
enum wimax_st wimax_state;
might_sleep();
d_fnstart(3, dev, "(wimax_dev %p state %u)\n", wimax_dev, state);
if (wimax_dev->rf_sw == state)
goto out_no_change;
if (wimax_dev->op_rfkill_sw_toggle != NULL)
result = wimax_dev->op_rfkill_sw_toggle(wimax_dev, state);
else if (state == WIMAX_RF_OFF) /* No op? can't turn off */
result = -ENXIO;
else /* No op? can turn on */
result = 0; /* should never happen tho */
if (result >= 0) {
result = 0;
wimax_dev->rf_sw = state;
wimax_state = state == WIMAX_RF_ON ?
WIMAX_ST_READY : WIMAX_ST_RADIO_OFF;
__wimax_state_change(wimax_dev, wimax_state);
}
out_no_change:
d_fnend(3, dev, "(wimax_dev %p state %u) = %d\n",
wimax_dev, state, result);
return result;
}
/*
* Translate from rfkill state to wimax state
*
* NOTE: Special state handling rules here
*
* Just pretend the call didn't happen if we are in a state where
* we know for sure it cannot be handled (WIMAX_ST_DOWN or
* __WIMAX_ST_QUIESCING). rfkill() needs it to register and
* unregister, as it will run this path.
*
* NOTE: This call will block until the operation is completed.
*/
static int wimax_rfkill_set_radio_block(void *data, bool blocked)
{
int result;
struct wimax_dev *wimax_dev = data;
struct device *dev = wimax_dev_to_dev(wimax_dev);
enum wimax_rf_state rf_state;
d_fnstart(3, dev, "(wimax_dev %p blocked %u)\n", wimax_dev, blocked);
rf_state = WIMAX_RF_ON;
if (blocked)
rf_state = WIMAX_RF_OFF;
mutex_lock(&wimax_dev->mutex);
if (wimax_dev->state <= __WIMAX_ST_QUIESCING)
result = 0;
else
result = __wimax_rf_toggle_radio(wimax_dev, rf_state);
mutex_unlock(&wimax_dev->mutex);
d_fnend(3, dev, "(wimax_dev %p blocked %u) = %d\n",
wimax_dev, blocked, result);
return result;
}
static const struct rfkill_ops wimax_rfkill_ops = {
.set_block = wimax_rfkill_set_radio_block,
};
/**
* wimax_rfkill - Set the software RF switch state for a WiMAX device
*
* @wimax_dev: WiMAX device descriptor
*
* @state: New RF state.
*
* Returns:
*
* >= 0 toggle state if ok, < 0 errno code on error. The toggle state
* is returned as a bitmap, bit 0 being the hardware RF state, bit 1
* the software RF state.
*
* 0 means disabled (%WIMAX_RF_ON, radio on), 1 means enabled radio
* off (%WIMAX_RF_OFF).
*
* Description:
*
* Called by the user when he wants to request the WiMAX radio to be
* switched on (%WIMAX_RF_ON) or off (%WIMAX_RF_OFF). With
* %WIMAX_RF_QUERY, just the current state is returned.
*
* NOTE:
*
* This call will block until the operation is complete.
*/
int wimax_rfkill(struct wimax_dev *wimax_dev, enum wimax_rf_state state)
{
int result;
struct device *dev = wimax_dev_to_dev(wimax_dev);
d_fnstart(3, dev, "(wimax_dev %p state %u)\n", wimax_dev, state);
mutex_lock(&wimax_dev->mutex);
result = wimax_dev_is_ready(wimax_dev);
if (result < 0) {
/* While initializing, < 1.4.3 wimax-tools versions use
* this call to check if the device is a valid WiMAX
* device; so we allow it to proceed always,
* considering the radios are all off. */
if (result == -ENOMEDIUM && state == WIMAX_RF_QUERY)
result = WIMAX_RF_OFF << 1 | WIMAX_RF_OFF;
goto error_not_ready;
}
switch (state) {
case WIMAX_RF_ON:
case WIMAX_RF_OFF:
result = __wimax_rf_toggle_radio(wimax_dev, state);
if (result < 0)
goto error;
rfkill_set_sw_state(wimax_dev->rfkill, state == WIMAX_RF_OFF);
break;
case WIMAX_RF_QUERY:
break;
default:
result = -EINVAL;
goto error;
}
result = wimax_dev->rf_sw << 1 | wimax_dev->rf_hw;
error:
error_not_ready:
mutex_unlock(&wimax_dev->mutex);
d_fnend(3, dev, "(wimax_dev %p state %u) = %d\n",
wimax_dev, state, result);
return result;
}
EXPORT_SYMBOL(wimax_rfkill);
/*
* Register a new WiMAX device's RF Kill support
*
* WARNING: wimax_dev->mutex must be unlocked
*/
int wimax_rfkill_add(struct wimax_dev *wimax_dev)
{
int result;
struct rfkill *rfkill;
struct device *dev = wimax_dev_to_dev(wimax_dev);
d_fnstart(3, dev, "(wimax_dev %p)\n", wimax_dev);
/* Initialize RF Kill */
result = -ENOMEM;
rfkill = rfkill_alloc(wimax_dev->name, dev, RFKILL_TYPE_WIMAX,
&wimax_rfkill_ops, wimax_dev);
if (rfkill == NULL)
goto error_rfkill_allocate;
d_printf(1, dev, "rfkill %p\n", rfkill);
wimax_dev->rfkill = rfkill;
rfkill_init_sw_state(rfkill, 1);
result = rfkill_register(wimax_dev->rfkill);
if (result < 0)
goto error_rfkill_register;
/* If there is no SW toggle op, SW RFKill is always on */
if (wimax_dev->op_rfkill_sw_toggle == NULL)
wimax_dev->rf_sw = WIMAX_RF_ON;
d_fnend(3, dev, "(wimax_dev %p) = 0\n", wimax_dev);
return 0;
error_rfkill_register:
rfkill_destroy(wimax_dev->rfkill);
error_rfkill_allocate:
d_fnend(3, dev, "(wimax_dev %p) = %d\n", wimax_dev, result);
return result;
}
/*
* Deregister a WiMAX device's RF Kill support
*
* Ick, we can't call rfkill_free() after rfkill_unregister()...oh
* well.
*
* WARNING: wimax_dev->mutex must be unlocked
*/
void wimax_rfkill_rm(struct wimax_dev *wimax_dev)
{
struct device *dev = wimax_dev_to_dev(wimax_dev);
d_fnstart(3, dev, "(wimax_dev %p)\n", wimax_dev);
rfkill_unregister(wimax_dev->rfkill);
rfkill_destroy(wimax_dev->rfkill);
d_fnend(3, dev, "(wimax_dev %p)\n", wimax_dev);
}
/*
* Exporting to user space over generic netlink
*
* Parse the rfkill command from user space, return a combination
* value that describe the states of the different toggles.
*
* Only one attribute: the new state requested (on, off or no change,
* just query).
*/
int wimax_gnl_doit_rfkill(struct sk_buff *skb, struct genl_info *info)
{
int result, ifindex;
struct wimax_dev *wimax_dev;
struct device *dev;
enum wimax_rf_state new_state;
d_fnstart(3, NULL, "(skb %p info %p)\n", skb, info);
result = -ENODEV;
if (info->attrs[WIMAX_GNL_RFKILL_IFIDX] == NULL) {
pr_err("WIMAX_GNL_OP_RFKILL: can't find IFIDX attribute\n");
goto error_no_wimax_dev;
}
ifindex = nla_get_u32(info->attrs[WIMAX_GNL_RFKILL_IFIDX]);
wimax_dev = wimax_dev_get_by_genl_info(info, ifindex);
if (wimax_dev == NULL)
goto error_no_wimax_dev;
dev = wimax_dev_to_dev(wimax_dev);
result = -EINVAL;
if (info->attrs[WIMAX_GNL_RFKILL_STATE] == NULL) {
dev_err(dev, "WIMAX_GNL_RFKILL: can't find RFKILL_STATE "
"attribute\n");
goto error_no_pid;
}
new_state = nla_get_u32(info->attrs[WIMAX_GNL_RFKILL_STATE]);
/* Execute the operation and send the result back to user space */
result = wimax_rfkill(wimax_dev, new_state);
error_no_pid:
dev_put(wimax_dev->net_dev);
error_no_wimax_dev:
d_fnend(3, NULL, "(skb %p info %p) = %d\n", skb, info, result);
return result;
}