diff options
Diffstat (limited to 'kernel/net/wimax/op-rfkill.c')
| -rw-r--r-- | kernel/net/wimax/op-rfkill.c | 447 |
1 files changed, 447 insertions, 0 deletions
diff --git a/kernel/net/wimax/op-rfkill.c b/kernel/net/wimax/op-rfkill.c new file mode 100644 index 000000000..7d730543f --- /dev/null +++ b/kernel/net/wimax/op-rfkill.c @@ -0,0 +1,447 @@ +/* + * 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 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; +} |