// SPDX-License-Identifier: GPL-2.0-only
/*
* Linux WiMAX
* Implement and export a method for resetting a WiMAX device
*
* Copyright (C) 2008 Intel Corporation <linux-wimax@intel.com>
* Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
*
* This implements a simple synchronous call to reset a WiMAX device.
*
* Resets aim at being warm, keeping the device handles active;
* however, when that fails, it falls back to a cold reset (that will
* disconnect and reconnect the device).
*/
#include <net/wimax.h>
#include <net/genetlink.h>
#include <linux/wimax.h>
#include <linux/security.h>
#include <linux/export.h>
#include "wimax-internal.h"
#define D_SUBMODULE op_reset
#include "debug-levels.h"
/**
* wimax_reset - Reset a WiMAX device
*
* @wimax_dev: WiMAX device descriptor
*
* Returns:
*
* %0 if ok and a warm reset was done (the device still exists in
* the system).
*
* -%ENODEV if a cold/bus reset had to be done (device has
* disconnected and reconnected, so current handle is not valid
* any more).
*
* -%EINVAL if the device is not even registered.
*
* Any other negative error code shall be considered as
* non-recoverable.
*
* Description:
*
* Called when wanting to reset the device for any reason. Device is
* taken back to power on status.
*
* This call blocks; on successful return, the device has completed the
* reset process and is ready to operate.
*/
int wimax_reset(struct wimax_dev *wimax_dev)
{
int result = -EINVAL;
struct device *dev = wimax_dev_to_dev(wimax_dev);
enum wimax_st state;
might_sleep();
d_fnstart(3, dev, "(wimax_dev %p)\n", wimax_dev);
mutex_lock(&wimax_dev->mutex);
dev_hold(wimax_dev->net_dev);
state = wimax_dev->state;
mutex_unlock(&wimax_dev->mutex);
if (state >= WIMAX_ST_DOWN) {
mutex_lock(&wimax_dev->mutex_reset);
result = wimax_dev->op_reset(wimax_dev);
mutex_unlock(&wimax_dev->mutex_reset);
}
dev_put(wimax_dev->net_dev);
d_fnend(3, dev, "(wimax_dev %p) = %d\n", wimax_dev, result);
return result;
}
EXPORT_SYMBOL(wimax_reset);
/*
* Exporting to user space over generic netlink
*
* Parse the reset command from user space, return error code.
*
* No attributes.
*/
int wimax_gnl_doit_reset(struct sk_buff *skb, struct genl_info *info)
{
int result, ifindex;
struct wimax_dev *wimax_dev;
d_fnstart(3, NULL, "(skb %p info %p)\n", skb, info);
result = -ENODEV;
if (info->attrs[WIMAX_GNL_RESET_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_RESET_IFIDX]);
wimax_dev = wimax_dev_get_by_genl_info(info, ifindex);
if (wimax_dev == NULL)
goto error_no_wimax_dev;
/* Execute the operation and send the result back to user space */
result = wimax_reset(wimax_dev);
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;
}