linux/drivers/net/wireless/realtek/rtw89/util.h

/* SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
 * Copyright(c) 2019-2020  Realtek Corporation
 */
#ifndef __RTW89_UTIL_H__
#define __RTW89_UTIL_H__

#include "core.h"

#define rtw89_iterate_vifs_bh(rtwdev, iterator, data)                          \
	ieee80211_iterate_active_interfaces_atomic((rtwdev)->hw,               \
			IEEE80211_IFACE_ITER_NORMAL, iterator, data)

/* call this function with rtwdev->mutex is held */
#define rtw89_for_each_rtwvif(rtwdev, rtwvif)				       \
	list_for_each_entry(rtwvif, &(rtwdev)->rtwvifs_list, list)

/* The result of negative dividend and positive divisor is undefined, but it
 * should be one case of round-down or round-up. So, make it round-down if the
 * result is round-up.
 * Note: the maximum value of divisor is 0x7FFF_FFFF, because we cast it to
 *       signed value to make compiler to use signed divide instruction.
 */
static inline s32 s32_div_u32_round_down(s32 dividend, u32 divisor, s32 *remainder)
{
	s32 i_divisor = (s32)divisor;
	s32 i_remainder;
	s32 quotient;

	quotient = dividend / i_divisor;
	i_remainder = dividend % i_divisor;

	if (i_remainder < 0) {
		quotient--;
		i_remainder += i_divisor;
	}

	if (remainder)
		*remainder = i_remainder;
	return quotient;
}

static inline s32 s32_div_u32_round_closest(s32 dividend, u32 divisor)
{
	return s32_div_u32_round_down(dividend + divisor / 2, divisor, NULL);
}

#endif