/*
 * Copyright (c) 2004 Video54 Technologies, Inc.
 * Copyright (c) 2004-2011 Atheros Communications, Inc.
 *
 * 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.
 */

#include <linux/slab.h>
#include <linux/export.h>

#include "ath9k.h"

static const struct ath_rate_table ar5416_11na_ratetable = {
        68,
        8, /* MCS start */
        {
                [0] = { RC_L_SDT, WLAN_RC_PHY_OFDM, 6000,
                        5400, 0, 12 }, /* 6 Mb */
                [1] = { RC_L_SDT, WLAN_RC_PHY_OFDM, 9000,
                        7800,  1, 18 }, /* 9 Mb */
                [2] = { RC_L_SDT, WLAN_RC_PHY_OFDM, 12000,
                        10000, 2, 24 }, /* 12 Mb */
                [3] = { RC_L_SDT, WLAN_RC_PHY_OFDM, 18000,
                        13900, 3, 36 }, /* 18 Mb */
                [4] = { RC_L_SDT, WLAN_RC_PHY_OFDM, 24000,
                        17300, 4, 48 }, /* 24 Mb */
                [5] = { RC_L_SDT, WLAN_RC_PHY_OFDM, 36000,
                        23000, 5, 72 }, /* 36 Mb */
                [6] = { RC_L_SDT, WLAN_RC_PHY_OFDM, 48000,
                        27400, 6, 96 }, /* 48 Mb */
                [7] = { RC_L_SDT, WLAN_RC_PHY_OFDM, 54000,
                        29300, 7, 108 }, /* 54 Mb */
                [8] = { RC_HT_SDT_2040, WLAN_RC_PHY_HT_20_SS, 6500,
                        6400, 0, 0 }, /* 6.5 Mb */
                [9] = { RC_HT_SDT_20, WLAN_RC_PHY_HT_20_SS, 13000,
                        12700, 1, 1 }, /* 13 Mb */
                [10] = { RC_HT_SDT_20, WLAN_RC_PHY_HT_20_SS, 19500,
                        18800, 2, 2 }, /* 19.5 Mb */
                [11] = { RC_HT_SD_20, WLAN_RC_PHY_HT_20_SS, 26000,
                        25000, 3, 3 }, /* 26 Mb */
                [12] = { RC_HT_SD_20, WLAN_RC_PHY_HT_20_SS, 39000,
                        36700, 4, 4 }, /* 39 Mb */
                [13] = { RC_HT_S_20, WLAN_RC_PHY_HT_20_SS, 52000,
                        48100, 5, 5 }, /* 52 Mb */
                [14] = { RC_HT_S_20, WLAN_RC_PHY_HT_20_SS, 58500,
                        53500, 6, 6 }, /* 58.5 Mb */
                [15] = { RC_HT_S_20, WLAN_RC_PHY_HT_20_SS, 65000,
                        59000, 7, 7 }, /* 65 Mb */
                [16] = { RC_HT_S_20, WLAN_RC_PHY_HT_20_SS_HGI, 72200,
                        65400, 7, 7 }, /* 75 Mb */
                [17] = { RC_INVALID, WLAN_RC_PHY_HT_20_DS, 13000,
                        12700, 8, 8 }, /* 13 Mb */
                [18] = { RC_HT_T_20, WLAN_RC_PHY_HT_20_DS, 26000,
                        24800, 9, 9 }, /* 26 Mb */
                [19] = { RC_HT_T_20, WLAN_RC_PHY_HT_20_DS, 39000,
                        36600, 10, 10 }, /* 39 Mb */
                [20] = { RC_HT_DT_20, WLAN_RC_PHY_HT_20_DS, 52000,
                        48100, 11, 11 }, /* 52 Mb */
                [21] = { RC_HT_DT_20, WLAN_RC_PHY_HT_20_DS, 78000,
                        69500, 12, 12 }, /* 78 Mb */
                [22] = { RC_HT_DT_20, WLAN_RC_PHY_HT_20_DS, 104000,
                        89500, 13, 13 }, /* 104 Mb */
                [23] = { RC_HT_DT_20, WLAN_RC_PHY_HT_20_DS, 117000,
                        98900, 14, 14 }, /* 117 Mb */
                [24] = { RC_HT_DT_20, WLAN_RC_PHY_HT_20_DS, 130000,
                        108300, 15, 15 }, /* 130 Mb */
                [25] = { RC_HT_DT_20, WLAN_RC_PHY_HT_20_DS_HGI, 144400,
                        120000, 15, 15 }, /* 144.4 Mb */
                [26] = {  RC_INVALID, WLAN_RC_PHY_HT_20_TS, 19500,
                        17400, 16, 16 }, /* 19.5 Mb */
                [27] = {  RC_INVALID, WLAN_RC_PHY_HT_20_TS, 39000,
                        35100, 17, 17 }, /* 39 Mb */
                [28] = {  RC_INVALID, WLAN_RC_PHY_HT_20_TS, 58500,
                        52600, 18, 18 }, /* 58.5 Mb */
                [29] = {  RC_INVALID, WLAN_RC_PHY_HT_20_TS, 78000,
                        70400, 19, 19 }, /* 78 Mb */
                [30] = {  RC_INVALID, WLAN_RC_PHY_HT_20_TS, 117000,
                        104900, 20, 20 }, /* 117 Mb */
                [31] = {  RC_INVALID, WLAN_RC_PHY_HT_20_TS_HGI, 130000,
                        115800, 20, 20 }, /* 130 Mb*/
                [32] = {  RC_HT_T_20, WLAN_RC_PHY_HT_20_TS, 156000,
                        137200, 21, 21 }, /* 156 Mb */
                [33] = {  RC_HT_T_20, WLAN_RC_PHY_HT_20_TS_HGI, 173300,
                        151100, 21, 21 }, /* 173.3 Mb */
                [34] = {  RC_HT_T_20, WLAN_RC_PHY_HT_20_TS, 175500,
                        152800, 22, 22 }, /* 175.5 Mb */
                [35] = {  RC_HT_T_20, WLAN_RC_PHY_HT_20_TS_HGI, 195000,
                        168400, 22, 22 }, /* 195 Mb*/
                [36] = {  RC_HT_T_20, WLAN_RC_PHY_HT_20_TS, 195000,
                        168400, 23, 23 }, /* 195 Mb */
                [37] = {  RC_HT_T_20, WLAN_RC_PHY_HT_20_TS_HGI, 216700,
                        185000, 23, 23 }, /* 216.7 Mb */
                [38] = { RC_HT_SDT_40, WLAN_RC_PHY_HT_40_SS, 13500,
                        13200, 0, 0 }, /* 13.5 Mb*/
                [39] = { RC_HT_SDT_40, WLAN_RC_PHY_HT_40_SS, 27500,
                        25900, 1, 1 }, /* 27.0 Mb*/
                [40] = { RC_HT_SDT_40, WLAN_RC_PHY_HT_40_SS, 40500,
                        38600, 2, 2 }, /* 40.5 Mb*/
                [41] = { RC_HT_SD_40, WLAN_RC_PHY_HT_40_SS, 54000,
                        49800, 3, 3 }, /* 54 Mb */
                [42] = { RC_HT_SD_40, WLAN_RC_PHY_HT_40_SS, 81500,
                        72200, 4, 4 }, /* 81 Mb */
                [43] = { RC_HT_S_40, WLAN_RC_PHY_HT_40_SS, 108000,
                        92900, 5, 5 }, /* 108 Mb */
                [44] = { RC_HT_S_40, WLAN_RC_PHY_HT_40_SS, 121500,
                        102700, 6, 6 }, /* 121.5 Mb*/
                [45] = { RC_HT_S_40, WLAN_RC_PHY_HT_40_SS, 135000,
                        112000, 7, 7 }, /* 135 Mb */
                [46] = { RC_HT_S_40, WLAN_RC_PHY_HT_40_SS_HGI, 150000,
                        122000, 7, 7 }, /* 150 Mb */
                [47] = { RC_INVALID, WLAN_RC_PHY_HT_40_DS, 27000,
                        25800, 8, 8 }, /* 27 Mb */
                [48] = { RC_HT_T_40, WLAN_RC_PHY_HT_40_DS, 54000,
                        49800, 9, 9 }, /* 54 Mb */
                [49] = { RC_HT_T_40, WLAN_RC_PHY_HT_40_DS, 81000,
                        71900, 10, 10 }, /* 81 Mb */
                [50] = { RC_HT_DT_40, WLAN_RC_PHY_HT_40_DS, 108000,
                        92500, 11, 11 }, /* 108 Mb */
                [51] = { RC_HT_DT_40, WLAN_RC_PHY_HT_40_DS, 162000,
                        130300, 12, 12 }, /* 162 Mb */
                [52] = { RC_HT_DT_40, WLAN_RC_PHY_HT_40_DS, 216000,
                        162800, 13, 13 }, /* 216 Mb */
                [53] = { RC_HT_DT_40, WLAN_RC_PHY_HT_40_DS, 243000,
                        178200, 14, 14 }, /* 243 Mb */
                [54] = { RC_HT_DT_40, WLAN_RC_PHY_HT_40_DS, 270000,
                        192100, 15, 15 }, /* 270 Mb */
                [55] = { RC_HT_DT_40, WLAN_RC_PHY_HT_40_DS_HGI, 300000,
                        207000, 15, 15 }, /* 300 Mb */
                [56] = {  RC_INVALID, WLAN_RC_PHY_HT_40_TS, 40500,
                        36100, 16, 16 }, /* 40.5 Mb */
                [57] = {  RC_INVALID, WLAN_RC_PHY_HT_40_TS, 81000,
                        72900, 17, 17 }, /* 81 Mb */
                [58] = {  RC_INVALID, WLAN_RC_PHY_HT_40_TS, 121500,
                        108300, 18, 18 }, /* 121.5 Mb */
                [59] = {  RC_INVALID, WLAN_RC_PHY_HT_40_TS, 162000,
                        142000, 19, 19 }, /*  162 Mb */
                [60] = {  RC_INVALID, WLAN_RC_PHY_HT_40_TS, 243000,
                        205100, 20, 20 }, /*  243 Mb */
                [61] = {  RC_INVALID, WLAN_RC_PHY_HT_40_TS_HGI, 270000,
                        224700, 20, 20 }, /*  270 Mb */
                [62] = {  RC_HT_T_40, WLAN_RC_PHY_HT_40_TS, 324000,
                        263100, 21, 21 }, /*  324 Mb */
                [63] = {  RC_HT_T_40, WLAN_RC_PHY_HT_40_TS_HGI, 360000,
                        288000, 21, 21 }, /*  360 Mb */
                [64] = {  RC_HT_T_40, WLAN_RC_PHY_HT_40_TS, 364500,
                        290700, 22, 22 }, /* 364.5 Mb */
                [65] = {  RC_HT_T_40, WLAN_RC_PHY_HT_40_TS_HGI, 405000,
                        317200, 22, 22 }, /* 405 Mb */
                [66] = {  RC_HT_T_40, WLAN_RC_PHY_HT_40_TS, 405000,
                        317200, 23, 23 }, /* 405 Mb */
                [67] = {  RC_HT_T_40, WLAN_RC_PHY_HT_40_TS_HGI, 450000,
                        346400, 23, 23 }, /* 450 Mb */
        },
        50,  /* probe interval */
        WLAN_RC_HT_FLAG,  /* Phy rates allowed initially */
};

/* 4ms frame limit not used for NG mode.  The values filled
 * for HT are the 64K max aggregate limit */

static const struct ath_rate_table ar5416_11ng_ratetable = {
        72,
        12, /* MCS start */
        {
                [0] = { RC_ALL, WLAN_RC_PHY_CCK, 1000,
                        900, 0, 2 }, /* 1 Mb */
                [1] = { RC_ALL, WLAN_RC_PHY_CCK, 2000,
                        1900, 1, 4 }, /* 2 Mb */
                [2] = { RC_ALL, WLAN_RC_PHY_CCK, 5500,
                        4900, 2, 11 }, /* 5.5 Mb */
                [3] = { RC_ALL, WLAN_RC_PHY_CCK, 11000,
                        8100, 3, 22 }, /* 11 Mb */
                [4] = { RC_INVALID, WLAN_RC_PHY_OFDM, 6000,
                        5400, 4, 12 }, /* 6 Mb */
                [5] = { RC_INVALID, WLAN_RC_PHY_OFDM, 9000,
                        7800, 5, 18 }, /* 9 Mb */
                [6] = { RC_L_SDT, WLAN_RC_PHY_OFDM, 12000,
                        10100, 6, 24 }, /* 12 Mb */
                [7] = { RC_L_SDT, WLAN_RC_PHY_OFDM, 18000,
                        14100, 7, 36 }, /* 18 Mb */
                [8] = { RC_L_SDT, WLAN_RC_PHY_OFDM, 24000,
                        17700, 8, 48 }, /* 24 Mb */
                [9] = { RC_L_SDT, WLAN_RC_PHY_OFDM, 36000,
                        23700, 9, 72 }, /* 36 Mb */
                [10] = { RC_L_SDT, WLAN_RC_PHY_OFDM, 48000,
                        27400, 10, 96 }, /* 48 Mb */
                [11] = { RC_L_SDT, WLAN_RC_PHY_OFDM, 54000,
                        30900, 11, 108 }, /* 54 Mb */
                [12] = { RC_INVALID, WLAN_RC_PHY_HT_20_SS, 6500,
                        6400, 0, 0 }, /* 6.5 Mb */
                [13] = { RC_HT_SDT_20, WLAN_RC_PHY_HT_20_SS, 13000,
                        12700, 1, 1 }, /* 13 Mb */
                [14] = { RC_HT_SDT_20, WLAN_RC_PHY_HT_20_SS, 19500,
                        18800, 2, 2 }, /* 19.5 Mb*/
                [15] = { RC_HT_SD_20, WLAN_RC_PHY_HT_20_SS, 26000,
                        25000, 3, 3 }, /* 26 Mb */
                [16] = { RC_HT_SD_20, WLAN_RC_PHY_HT_20_SS, 39000,
                        36700, 4, 4 }, /* 39 Mb */
                [17] = { RC_HT_S_20, WLAN_RC_PHY_HT_20_SS, 52000,
                        48100, 5, 5 }, /* 52 Mb */
                [18] = { RC_HT_S_20, WLAN_RC_PHY_HT_20_SS, 58500,
                        53500, 6, 6 }, /* 58.5 Mb */
                [19] = { RC_HT_S_20, WLAN_RC_PHY_HT_20_SS, 65000,
                        59000, 7, 7 }, /* 65 Mb */
                [20] = { RC_HT_S_20, WLAN_RC_PHY_HT_20_SS_HGI, 72200,
                        65400, 7, 7 }, /* 65 Mb*/
                [21] = { RC_INVALID, WLAN_RC_PHY_HT_20_DS, 13000,
                        12700, 8, 8 }, /* 13 Mb */
                [22] = { RC_HT_T_20, WLAN_RC_PHY_HT_20_DS, 26000,
                        24800, 9, 9 }, /* 26 Mb */
                [23] = { RC_HT_T_20, WLAN_RC_PHY_HT_20_DS, 39000,
                        36600, 10, 10 }, /* 39 Mb */
                [24] = { RC_HT_DT_20, WLAN_RC_PHY_HT_20_DS, 52000,
                        48100, 11, 11 }, /* 52 Mb */
                [25] = { RC_HT_DT_20, WLAN_RC_PHY_HT_20_DS, 78000,
                        69500, 12, 12 }, /* 78 Mb */
                [26] = { RC_HT_DT_20, WLAN_RC_PHY_HT_20_DS, 104000,
                        89500, 13, 13 }, /* 104 Mb */
                [27] = { RC_HT_DT_20, WLAN_RC_PHY_HT_20_DS, 117000,
                        98900, 14, 14 }, /* 117 Mb */
                [28] = { RC_HT_DT_20, WLAN_RC_PHY_HT_20_DS, 130000,
                        108300, 15, 15 }, /* 130 Mb */
                [29] = { RC_HT_DT_20, WLAN_RC_PHY_HT_20_DS_HGI, 144400,
                        120000, 15, 15 }, /* 144.4 Mb */
                [30] = {  RC_INVALID, WLAN_RC_PHY_HT_20_TS, 19500,
                        17400, 16, 16 }, /* 19.5 Mb */
                [31] = {  RC_INVALID, WLAN_RC_PHY_HT_20_TS, 39000,
                        35100, 17, 17 }, /* 39 Mb */
                [32] = {  RC_INVALID, WLAN_RC_PHY_HT_20_TS, 58500,
                        52600, 18, 18 }, /* 58.5 Mb */
                [33] = {  RC_INVALID, WLAN_RC_PHY_HT_20_TS, 78000,
                        70400, 19, 19 }, /* 78 Mb */
                [34] = {  RC_INVALID, WLAN_RC_PHY_HT_20_TS, 117000,
                        104900, 20, 20 }, /* 117 Mb */
                [35] = {  RC_INVALID, WLAN_RC_PHY_HT_20_TS_HGI, 130000,
                        115800, 20, 20 }, /* 130 Mb */
                [36] = {  RC_HT_T_20, WLAN_RC_PHY_HT_20_TS, 156000,
                        137200, 21, 21 }, /* 156 Mb */
                [37] = {  RC_HT_T_20, WLAN_RC_PHY_HT_20_TS_HGI, 173300,
                        151100, 21, 21 }, /* 173.3 Mb */
                [38] = {  RC_HT_T_20, WLAN_RC_PHY_HT_20_TS, 175500,
                        152800, 22, 22 }, /* 175.5 Mb */
                [39] = {  RC_HT_T_20, WLAN_RC_PHY_HT_20_TS_HGI, 195000,
                        168400, 22, 22 }, /* 195 Mb */
                [40] = {  RC_HT_T_20, WLAN_RC_PHY_HT_20_TS, 195000,
                        168400, 23, 23 }, /* 195 Mb */
                [41] = {  RC_HT_T_20, WLAN_RC_PHY_HT_20_TS_HGI, 216700,
                        185000, 23, 23 }, /* 216.7 Mb */
                [42] = { RC_HT_SDT_40, WLAN_RC_PHY_HT_40_SS, 13500,
                        13200, 0, 0 }, /* 13.5 Mb */
                [43] = { RC_HT_SDT_40, WLAN_RC_PHY_HT_40_SS, 27500,
                        25900, 1, 1 }, /* 27.0 Mb */
                [44] = { RC_HT_SDT_40, WLAN_RC_PHY_HT_40_SS, 40500,
                        38600, 2, 2 }, /* 40.5 Mb */
                [45] = { RC_HT_SD_40, WLAN_RC_PHY_HT_40_SS, 54000,
                        49800, 3, 3 }, /* 54 Mb */
                [46] = { RC_HT_SD_40, WLAN_RC_PHY_HT_40_SS, 81500,
                        72200, 4, 4 }, /* 81 Mb */
                [47] = { RC_HT_S_40 , WLAN_RC_PHY_HT_40_SS, 108000,
                        92900, 5, 5 }, /* 108 Mb */
                [48] = { RC_HT_S_40, WLAN_RC_PHY_HT_40_SS, 121500,
                        102700, 6, 6 }, /* 121.5 Mb */
                [49] = { RC_HT_S_40, WLAN_RC_PHY_HT_40_SS, 135000,
                        112000, 7, 7 }, /* 135 Mb */
                [50] = { RC_HT_S_40, WLAN_RC_PHY_HT_40_SS_HGI, 150000,
                        122000, 7, 7 }, /* 150 Mb */
                [51] = { RC_INVALID, WLAN_RC_PHY_HT_40_DS, 27000,
                        25800, 8, 8 }, /* 27 Mb */
                [52] = { RC_HT_T_40, WLAN_RC_PHY_HT_40_DS, 54000,
                        49800, 9, 9 }, /* 54 Mb */
                [53] = { RC_HT_T_40, WLAN_RC_PHY_HT_40_DS, 81000,
                        71900, 10, 10 }, /* 81 Mb */
                [54] = { RC_HT_DT_40, WLAN_RC_PHY_HT_40_DS, 108000,
                        92500, 11, 11 }, /* 108 Mb */
                [55] = { RC_HT_DT_40, WLAN_RC_PHY_HT_40_DS, 162000,
                        130300, 12, 12 }, /* 162 Mb */
                [56] = { RC_HT_DT_40, WLAN_RC_PHY_HT_40_DS, 216000,
                        162800, 13, 13 }, /* 216 Mb */
                [57] = { RC_HT_DT_40, WLAN_RC_PHY_HT_40_DS, 243000,
                        178200, 14, 14 }, /* 243 Mb */
                [58] = { RC_HT_DT_40, WLAN_RC_PHY_HT_40_DS, 270000,
                        192100, 15, 15 }, /* 270 Mb */
                [59] = { RC_HT_DT_40, WLAN_RC_PHY_HT_40_DS_HGI, 300000,
                        207000, 15, 15 }, /* 300 Mb */
                [60] = {  RC_INVALID, WLAN_RC_PHY_HT_40_TS, 40500,
                        36100, 16, 16 }, /* 40.5 Mb */
                [61] = {  RC_INVALID, WLAN_RC_PHY_HT_40_TS, 81000,
                        72900, 17, 17 }, /* 81 Mb */
                [62] = {  RC_INVALID, WLAN_RC_PHY_HT_40_TS, 121500,
                        108300, 18, 18 }, /* 121.5 Mb */
                [63] = {  RC_INVALID, WLAN_RC_PHY_HT_40_TS, 162000,
                        142000, 19, 19 }, /* 162 Mb */
                [64] = {  RC_INVALID, WLAN_RC_PHY_HT_40_TS, 243000,
                        205100, 20, 20 }, /* 243 Mb */
                [65] = {  RC_INVALID, WLAN_RC_PHY_HT_40_TS_HGI, 270000,
                        224700, 20, 20 }, /* 270 Mb */
                [66] = {  RC_HT_T_40, WLAN_RC_PHY_HT_40_TS, 324000,
                        263100, 21, 21 }, /* 324 Mb */
                [67] = {  RC_HT_T_40, WLAN_RC_PHY_HT_40_TS_HGI, 360000,
                        288000, 21, 21 }, /* 360 Mb */
                [68] = {  RC_HT_T_40, WLAN_RC_PHY_HT_40_TS, 364500,
                        290700, 22, 22 }, /* 364.5 Mb */
                [69] = {  RC_HT_T_40, WLAN_RC_PHY_HT_40_TS_HGI, 405000,
                        317200, 22, 22 }, /* 405 Mb */
                [70] = {  RC_HT_T_40, WLAN_RC_PHY_HT_40_TS, 405000,
                        317200, 23, 23 }, /* 405 Mb */
                [71] = {  RC_HT_T_40, WLAN_RC_PHY_HT_40_TS_HGI, 450000,
                        346400, 23, 23 }, /* 450 Mb */
        },
        50,  /* probe interval */
        WLAN_RC_HT_FLAG,  /* Phy rates allowed initially */
};

static const struct ath_rate_table ar5416_11a_ratetable = {
        8,
        0,
        {
                { RC_L_SDT, WLAN_RC_PHY_OFDM, 6000, /* 6 Mb */
                        5400, 0, 12},
                { RC_L_SDT, WLAN_RC_PHY_OFDM, 9000, /* 9 Mb */
                        7800,  1, 18},
                { RC_L_SDT, WLAN_RC_PHY_OFDM, 12000, /* 12 Mb */
                        10000, 2, 24},
                { RC_L_SDT, WLAN_RC_PHY_OFDM, 18000, /* 18 Mb */
                        13900, 3, 36},
                { RC_L_SDT, WLAN_RC_PHY_OFDM, 24000, /* 24 Mb */
                        17300, 4, 48},
                { RC_L_SDT, WLAN_RC_PHY_OFDM, 36000, /* 36 Mb */
                        23000, 5, 72},
                { RC_L_SDT, WLAN_RC_PHY_OFDM, 48000, /* 48 Mb */
                        27400, 6, 96},
                { RC_L_SDT, WLAN_RC_PHY_OFDM, 54000, /* 54 Mb */
                        29300, 7, 108},
        },
        50,  /* probe interval */
        0,   /* Phy rates allowed initially */
};

static const struct ath_rate_table ar5416_11g_ratetable = {
        12,
        0,
        {
                { RC_L_SDT, WLAN_RC_PHY_CCK, 1000, /* 1 Mb */
                        900, 0, 2},
                { RC_L_SDT, WLAN_RC_PHY_CCK, 2000, /* 2 Mb */
                        1900, 1, 4},
                { RC_L_SDT, WLAN_RC_PHY_CCK, 5500, /* 5.5 Mb */
                        4900, 2, 11},
                { RC_L_SDT, WLAN_RC_PHY_CCK, 11000, /* 11 Mb */
                        8100, 3, 22},
                { RC_INVALID, WLAN_RC_PHY_OFDM, 6000, /* 6 Mb */
                        5400, 4, 12},
                { RC_INVALID, WLAN_RC_PHY_OFDM, 9000, /* 9 Mb */
                        7800, 5, 18},
                { RC_L_SDT, WLAN_RC_PHY_OFDM, 12000, /* 12 Mb */
                        10000, 6, 24},
                { RC_L_SDT, WLAN_RC_PHY_OFDM, 18000, /* 18 Mb */
                        13900, 7, 36},
                { RC_L_SDT, WLAN_RC_PHY_OFDM, 24000, /* 24 Mb */
                        17300, 8, 48},
                { RC_L_SDT, WLAN_RC_PHY_OFDM, 36000, /* 36 Mb */
                        23000, 9, 72},
                { RC_L_SDT, WLAN_RC_PHY_OFDM, 48000, /* 48 Mb */
                        27400, 10, 96},
                { RC_L_SDT, WLAN_RC_PHY_OFDM, 54000, /* 54 Mb */
                        29300, 11, 108},
        },
        50,  /* probe interval */
        0,   /* Phy rates allowed initially */
};

static int ath_rc_get_rateindex(struct ath_rate_priv *ath_rc_priv,
                                struct ieee80211_tx_rate *rate)
{
        const struct ath_rate_table *rate_table = ath_rc_priv->rate_table;
        int rix, i, idx = 0;

        if (!(rate->flags & IEEE80211_TX_RC_MCS))
                return rate->idx;

        for (i = 0; i < ath_rc_priv->max_valid_rate; i++) {
                idx = ath_rc_priv->valid_rate_index[i];

                if (WLAN_RC_PHY_HT(rate_table->info[idx].phy) &&
                    rate_table->info[idx].ratecode == rate->idx)
                        break;
        }

        rix = idx;

        if (rate->flags & IEEE80211_TX_RC_SHORT_GI)
                rix++;

        return rix;
}

static void ath_rc_sort_validrates(struct ath_rate_priv *ath_rc_priv)
{
        const struct ath_rate_table *rate_table = ath_rc_priv->rate_table;
        u8 i, j, idx, idx_next;

        for (i = ath_rc_priv->max_valid_rate - 1; i > 0; i--) {
                for (j = 0; j <= i-1; j++) {
                        idx = ath_rc_priv->valid_rate_index[j];
                        idx_next = ath_rc_priv->valid_rate_index[j+1];

                        if (rate_table->info[idx].ratekbps >
                                rate_table->info[idx_next].ratekbps) {
                                ath_rc_priv->valid_rate_index[j] = idx_next;
                                ath_rc_priv->valid_rate_index[j+1] = idx;
                        }
                }
        }
}

static inline
int ath_rc_get_nextvalid_txrate(const struct ath_rate_table *rate_table,
                                struct ath_rate_priv *ath_rc_priv,
                                u8 cur_valid_txrate,
                                u8 *next_idx)
{
        u8 i;

        for (i = 0; i < ath_rc_priv->max_valid_rate - 1; i++) {
                if (ath_rc_priv->valid_rate_index[i] == cur_valid_txrate) {
                        *next_idx = ath_rc_priv->valid_rate_index[i+1];
                        return 1;
                }
        }

        /* No more valid rates */
        *next_idx = 0;

        return 0;
}

/* Return true only for single stream */

static int ath_rc_valid_phyrate(u32 phy, u32 capflag, int ignore_cw)
{
        if (WLAN_RC_PHY_HT(phy) && !(capflag & WLAN_RC_HT_FLAG))
                return 0;
        if (WLAN_RC_PHY_DS(phy) && !(capflag & WLAN_RC_DS_FLAG))
                return 0;
        if (WLAN_RC_PHY_TS(phy) && !(capflag & WLAN_RC_TS_FLAG))
                return 0;
        if (WLAN_RC_PHY_SGI(phy) && !(capflag & WLAN_RC_SGI_FLAG))
                return 0;
        if (!ignore_cw && WLAN_RC_PHY_HT(phy))
                if (WLAN_RC_PHY_40(phy) && !(capflag & WLAN_RC_40_FLAG))
                        return 0;
        return 1;
}

static inline int
ath_rc_get_lower_rix(struct ath_rate_priv *ath_rc_priv,
                     u8 cur_valid_txrate, u8 *next_idx)
{
        int8_t i;

        for (i = 1; i < ath_rc_priv->max_valid_rate ; i++) {
                if (ath_rc_priv->valid_rate_index[i] == cur_valid_txrate) {
                        *next_idx = ath_rc_priv->valid_rate_index[i-1];
                        return 1;
                }
        }

        return 0;
}

static u8 ath_rc_init_validrates(struct ath_rate_priv *ath_rc_priv)
{
        const struct ath_rate_table *rate_table = ath_rc_priv->rate_table;
        u8 i, hi = 0;

        for (i = 0; i < rate_table->rate_cnt; i++) {
                if (rate_table->info[i].rate_flags & RC_LEGACY) {
                        u32 phy = rate_table->info[i].phy;
                        u8 valid_rate_count = 0;

                        if (!ath_rc_valid_phyrate(phy, ath_rc_priv->ht_cap, 0))
                                continue;

                        valid_rate_count = ath_rc_priv->valid_phy_ratecnt[phy];

                        ath_rc_priv->valid_phy_rateidx[phy][valid_rate_count] = i;
                        ath_rc_priv->valid_phy_ratecnt[phy] += 1;
                        ath_rc_priv->valid_rate_index[i] = true;
                        hi = i;
                }
        }

        return hi;
}

static inline bool ath_rc_check_legacy(u8 rate, u8 dot11rate, u16 rate_flags,
                                       u32 phy, u32 capflag)
{
        if (rate != dot11rate || WLAN_RC_PHY_HT(phy))
                return false;

        if ((rate_flags & WLAN_RC_CAP_MODE(capflag)) != WLAN_RC_CAP_MODE(capflag))
                return false;

        if (!(rate_flags & WLAN_RC_CAP_STREAM(capflag)))
                return false;

        return true;
}

static inline bool ath_rc_check_ht(u8 rate, u8 dot11rate, u16 rate_flags,
                                   u32 phy, u32 capflag)
{
        if (rate != dot11rate || !WLAN_RC_PHY_HT(phy))
                return false;

        if (!WLAN_RC_PHY_HT_VALID(rate_flags, capflag))
                return false;

        if (!(rate_flags & WLAN_RC_CAP_STREAM(capflag)))
                return false;

        return true;
}

static u8 ath_rc_setvalid_rates(struct ath_rate_priv *ath_rc_priv, bool legacy)
{
        const struct ath_rate_table *rate_table = ath_rc_priv->rate_table;
        struct ath_rateset *rateset;
        u32 phy, capflag = ath_rc_priv->ht_cap;
        u16 rate_flags;
        u8 i, j, hi = 0, rate, dot11rate, valid_rate_count;

        if (legacy)
                rateset = &ath_rc_priv->neg_rates;
        else
                rateset = &ath_rc_priv->neg_ht_rates;

        for (i = 0; i < rateset->rs_nrates; i++) {
                for (j = 0; j < rate_table->rate_cnt; j++) {
                        phy = rate_table->info[j].phy;
                        rate_flags = rate_table->info[j].rate_flags;
                        rate = rateset->rs_rates[i];
                        dot11rate = rate_table->info[j].dot11rate;

                        if (legacy &&
                            !ath_rc_check_legacy(rate, dot11rate,
                                                 rate_flags, phy, capflag))
                                continue;

                        if (!legacy &&
                            !ath_rc_check_ht(rate, dot11rate,
                                             rate_flags, phy, capflag))
                                continue;

                        if (!ath_rc_valid_phyrate(phy, capflag, 0))
                                continue;

                        valid_rate_count = ath_rc_priv->valid_phy_ratecnt[phy];
                        ath_rc_priv->valid_phy_rateidx[phy][valid_rate_count] = j;
                        ath_rc_priv->valid_phy_ratecnt[phy] += 1;
                        ath_rc_priv->valid_rate_index[j] = true;
                        hi = max(hi, j);
                }
        }

        return hi;
}

static u8 ath_rc_get_highest_rix(struct ath_rate_priv *ath_rc_priv,
                                 int *is_probing)
{
        const struct ath_rate_table *rate_table = ath_rc_priv->rate_table;
        u32 best_thruput, this_thruput, now_msec;
        u8 rate, next_rate, best_rate, maxindex, minindex;
        int8_t index = 0;

        now_msec = jiffies_to_msecs(jiffies);
        *is_probing = 0;
        best_thruput = 0;
        maxindex = ath_rc_priv->max_valid_rate-1;
        minindex = 0;
        best_rate = minindex;

        /*
         * Try the higher rate first. It will reduce memory moving time
         * if we have very good channel characteristics.
         */
        for (index = maxindex; index >= minindex ; index--) {
                u8 per_thres;

                rate = ath_rc_priv->valid_rate_index[index];
                if (rate > ath_rc_priv->rate_max_phy)
                        continue;

                /*
                 * For TCP the average collision rate is around 11%,
                 * so we ignore PERs less than this.  This is to
                 * prevent the rate we are currently using (whose
                 * PER might be in the 10-15 range because of TCP
                 * collisions) looking worse than the next lower
                 * rate whose PER has decayed close to 0.  If we
                 * used to next lower rate, its PER would grow to
                 * 10-15 and we would be worse off then staying
                 * at the current rate.
                 */
                per_thres = ath_rc_priv->per[rate];
                if (per_thres < 12)
                        per_thres = 12;

                this_thruput = rate_table->info[rate].user_ratekbps *
                        (100 - per_thres);

                if (best_thruput <= this_thruput) {
                        best_thruput = this_thruput;
                        best_rate    = rate;
                }
        }

        rate = best_rate;

        /*
         * Must check the actual rate (ratekbps) to account for
         * non-monoticity of 11g's rate table
         */

        if (rate >= ath_rc_priv->rate_max_phy) {
                rate = ath_rc_priv->rate_max_phy;

                /* Probe the next allowed phy state */
                if (ath_rc_get_nextvalid_txrate(rate_table,
                                        ath_rc_priv, rate, &next_rate) &&
                    (now_msec - ath_rc_priv->probe_time >
                     rate_table->probe_interval) &&
                    (ath_rc_priv->hw_maxretry_pktcnt >= 1)) {
                        rate = next_rate;
                        ath_rc_priv->probe_rate = rate;
                        ath_rc_priv->probe_time = now_msec;
                        ath_rc_priv->hw_maxretry_pktcnt = 0;
                        *is_probing = 1;
                }
        }

        if (rate > (ath_rc_priv->rate_table_size - 1))
                rate = ath_rc_priv->rate_table_size - 1;

        if (RC_TS_ONLY(rate_table->info[rate].rate_flags) &&
            (ath_rc_priv->ht_cap & WLAN_RC_TS_FLAG))
                return rate;

        if (RC_DS_OR_LATER(rate_table->info[rate].rate_flags) &&
            (ath_rc_priv->ht_cap & (WLAN_RC_DS_FLAG | WLAN_RC_TS_FLAG)))
                return rate;

        if (RC_SS_OR_LEGACY(rate_table->info[rate].rate_flags))
                return rate;

        /* This should not happen */
        WARN_ON_ONCE(1);

        rate = ath_rc_priv->valid_rate_index[0];

        return rate;
}

static void ath_rc_rate_set_series(const struct ath_rate_table *rate_table,
                                   struct ieee80211_tx_rate *rate,
                                   struct ieee80211_tx_rate_control *txrc,
                                   u8 tries, u8 rix, int rtsctsenable)
{
        rate->count = tries;
        rate->idx = rate_table->info[rix].ratecode;

        if (txrc->rts || rtsctsenable)
                rate->flags |= IEEE80211_TX_RC_USE_RTS_CTS;

        if (WLAN_RC_PHY_HT(rate_table->info[rix].phy)) {
                rate->flags |= IEEE80211_TX_RC_MCS;
                if (WLAN_RC_PHY_40(rate_table->info[rix].phy) &&
                    conf_is_ht40(&txrc->hw->conf))
                        rate->flags |= IEEE80211_TX_RC_40_MHZ_WIDTH;
                if (WLAN_RC_PHY_SGI(rate_table->info[rix].phy))
                        rate->flags |= IEEE80211_TX_RC_SHORT_GI;
        }
}

static void ath_rc_rate_set_rtscts(struct ath_softc *sc,
                                   const struct ath_rate_table *rate_table,
                                   struct ieee80211_tx_info *tx_info)
{
        struct ieee80211_bss_conf *bss_conf;

        if (!tx_info->control.vif)
                return;
        /*
         * For legacy frames, mac80211 takes care of CTS protection.
         */
        if (!(tx_info->control.rates[0].flags & IEEE80211_TX_RC_MCS))
                return;

        bss_conf = &tx_info->control.vif->bss_conf;

        if (!bss_conf->basic_rates)
                return;

        /*
         * For now, use the lowest allowed basic rate for HT frames.
         */
        tx_info->control.rts_cts_rate_idx = __ffs(bss_conf->basic_rates);
}

static void ath_get_rate(void *priv, struct ieee80211_sta *sta, void *priv_sta,
                         struct ieee80211_tx_rate_control *txrc)
{
        struct ath_softc *sc = priv;
        struct ath_rate_priv *ath_rc_priv = priv_sta;
        const struct ath_rate_table *rate_table;
        struct sk_buff *skb = txrc->skb;
        struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
        struct ieee80211_tx_rate *rates = tx_info->control.rates;
        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
        __le16 fc = hdr->frame_control;
        u8 try_per_rate, i = 0, rix;
        int is_probe = 0;

        if (rate_control_send_low(sta, priv_sta, txrc))
                return;

        /*
         * For Multi Rate Retry we use a different number of
         * retry attempt counts. This ends up looking like this:
         *
         * MRR[0] = 4
         * MRR[1] = 4
         * MRR[2] = 4
         * MRR[3] = 8
         *
         */
        try_per_rate = 4;

        rate_table = ath_rc_priv->rate_table;
        rix = ath_rc_get_highest_rix(ath_rc_priv, &is_probe);

        if (conf_is_ht(&sc->hw->conf) &&
            (sta->ht_cap.cap & IEEE80211_HT_CAP_LDPC_CODING))
                tx_info->flags |= IEEE80211_TX_CTL_LDPC;

        if (conf_is_ht(&sc->hw->conf) &&
            (sta->ht_cap.cap & IEEE80211_HT_CAP_TX_STBC))
                tx_info->flags |= (1 << IEEE80211_TX_CTL_STBC_SHIFT);

        if (is_probe) {
                /*
                 * Set one try for probe rates. For the
                 * probes don't enable RTS.
                 */
                ath_rc_rate_set_series(rate_table, &rates[i++], txrc,
                                       1, rix, 0);
                /*
                 * Get the next tried/allowed rate.
                 * No RTS for the next series after the probe rate.
                 */
                ath_rc_get_lower_rix(ath_rc_priv, rix, &rix);
                ath_rc_rate_set_series(rate_table, &rates[i++], txrc,
                                       try_per_rate, rix, 0);

                tx_info->flags |= IEEE80211_TX_CTL_RATE_CTRL_PROBE;
        } else {
                /*
                 * Set the chosen rate. No RTS for first series entry.
                 */
                ath_rc_rate_set_series(rate_table, &rates[i++], txrc,
                                       try_per_rate, rix, 0);
        }

        for ( ; i < 4; i++) {
                /*
                 * Use twice the number of tries for the last MRR segment.
                 */
                if (i + 1 == 4)
                        try_per_rate = 8;

                ath_rc_get_lower_rix(ath_rc_priv, rix, &rix);

                /*
                 * All other rates in the series have RTS enabled.
                 */
                ath_rc_rate_set_series(rate_table, &rates[i], txrc,
                                       try_per_rate, rix, 1);
        }

        /*
         * NB:Change rate series to enable aggregation when operating
         * at lower MCS rates. When first rate in series is MCS2
         * in HT40 @ 2.4GHz, series should look like:
         *
         * {MCS2, MCS1, MCS0, MCS0}.
         *
         * When first rate in series is MCS3 in HT20 @ 2.4GHz, series should
         * look like:
         *
         * {MCS3, MCS2, MCS1, MCS1}
         *
         * So, set fourth rate in series to be same as third one for
         * above conditions.
         */
        if ((sc->hw->conf.chandef.chan->band == IEEE80211_BAND_2GHZ) &&
            (conf_is_ht(&sc->hw->conf))) {
                u8 dot11rate = rate_table->info[rix].dot11rate;
                u8 phy = rate_table->info[rix].phy;
                if (i == 4 &&
                    ((dot11rate == 2 && phy == WLAN_RC_PHY_HT_40_SS) ||
                     (dot11rate == 3 && phy == WLAN_RC_PHY_HT_20_SS))) {
                        rates[3].idx = rates[2].idx;
                        rates[3].flags = rates[2].flags;
                }
        }

        /*
         * Force hardware to use computed duration for next
         * fragment by disabling multi-rate retry, which
         * updates duration based on the multi-rate duration table.
         *
         * FIXME: Fix duration
         */
        if (ieee80211_has_morefrags(fc) ||
            (le16_to_cpu(hdr->seq_ctrl) & IEEE80211_SCTL_FRAG)) {
                rates[1].count = rates[2].count = rates[3].count = 0;
                rates[1].idx = rates[2].idx = rates[3].idx = 0;
                rates[0].count = ATH_TXMAXTRY;
        }

        ath_rc_rate_set_rtscts(sc, rate_table, tx_info);
}

static void ath_rc_update_per(struct ath_softc *sc,
                              const struct ath_rate_table *rate_table,
                              struct ath_rate_priv *ath_rc_priv,
                                  struct ieee80211_tx_info *tx_info,
                              int tx_rate, int xretries, int retries,
                              u32 now_msec)
{
        int count, n_bad_frames;
        u8 last_per;
        static const u32 nretry_to_per_lookup[10] = {
                100 * 0 / 1,
                100 * 1 / 4,
                100 * 1 / 2,
                100 * 3 / 4,
                100 * 4 / 5,
                100 * 5 / 6,
                100 * 6 / 7,
                100 * 7 / 8,
                100 * 8 / 9,
                100 * 9 / 10
        };

        last_per = ath_rc_priv->per[tx_rate];
        n_bad_frames = tx_info->status.ampdu_len - tx_info->status.ampdu_ack_len;

        if (xretries) {
                if (xretries == 1) {
                        ath_rc_priv->per[tx_rate] += 30;
                        if (ath_rc_priv->per[tx_rate] > 100)
                                ath_rc_priv->per[tx_rate] = 100;
                } else {
                        /* xretries == 2 */
                        count = ARRAY_SIZE(nretry_to_per_lookup);
                        if (retries >= count)
                                retries = count - 1;

                        /* new_PER = 7/8*old_PER + 1/8*(currentPER) */
                        ath_rc_priv->per[tx_rate] =
                                (u8)(last_per - (last_per >> 3) + (100 >> 3));
                }

                /* xretries == 1 or 2 */

                if (ath_rc_priv->probe_rate == tx_rate)
                        ath_rc_priv->probe_rate = 0;

        } else { /* xretries == 0 */
                count = ARRAY_SIZE(nretry_to_per_lookup);
                if (retries >= count)
                        retries = count - 1;

                if (n_bad_frames) {
                        /* new_PER = 7/8*old_PER + 1/8*(currentPER)
                         * Assuming that n_frames is not 0.  The current PER
                         * from the retries is 100 * retries / (retries+1),
                         * since the first retries attempts failed, and the
                         * next one worked.  For the one that worked,
                         * n_bad_frames subframes out of n_frames wored,
                         * so the PER for that part is
                         * 100 * n_bad_frames / n_frames, and it contributes
                         * 100 * n_bad_frames / (n_frames * (retries+1)) to
                         * the above PER.  The expression below is a
                         * simplified version of the sum of these two terms.
                         */
                        if (tx_info->status.ampdu_len > 0) {
                                int n_frames, n_bad_tries;
                                u8 cur_per, new_per;

                                n_bad_tries = retries * tx_info->status.ampdu_len +
                                        n_bad_frames;
                                n_frames = tx_info->status.ampdu_len * (retries + 1);
                                cur_per = (100 * n_bad_tries / n_frames) >> 3;
                                new_per = (u8)(last_per - (last_per >> 3) + cur_per);
                                ath_rc_priv->per[tx_rate] = new_per;
                        }
                } else {
                        ath_rc_priv->per[tx_rate] =
                                (u8)(last_per - (last_per >> 3) +
                                     (nretry_to_per_lookup[retries] >> 3));
                }


                /*
                 * If we got at most one retry then increase the max rate if
                 * this was a probe.  Otherwise, ignore the probe.
                 */
                if (ath_rc_priv->probe_rate && ath_rc_priv->probe_rate == tx_rate) {
                        if (retries > 0 || 2 * n_bad_frames > tx_info->status.ampdu_len) {
                                /*
                                 * Since we probed with just a single attempt,
                                 * any retries means the probe failed.  Also,
                                 * if the attempt worked, but more than half
                                 * the subframes were bad then also consider
                                 * the probe a failure.
                                 */
                                ath_rc_priv->probe_rate = 0;
                        } else {
                                u8 probe_rate = 0;

                                ath_rc_priv->rate_max_phy =
                                        ath_rc_priv->probe_rate;
                                probe_rate = ath_rc_priv->probe_rate;

                                if (ath_rc_priv->per[probe_rate] > 30)
                                        ath_rc_priv->per[probe_rate] = 20;

                                ath_rc_priv->probe_rate = 0;

                                /*
                                 * Since this probe succeeded, we allow the next
                                 * probe twice as soon.  This allows the maxRate
                                 * to move up faster if the probes are
                                 * successful.
                                 */
                                ath_rc_priv->probe_time =
                                        now_msec - rate_table->probe_interval / 2;
                        }
                }

                if (retries > 0) {
                        /*
                         * Don't update anything.  We don't know if
                         * this was because of collisions or poor signal.
                         */
                        ath_rc_priv->hw_maxretry_pktcnt = 0;
                } else {
                        /*
                         * It worked with no retries. First ignore bogus (small)
                         * rssi_ack values.
                         */
                        if (tx_rate == ath_rc_priv->rate_max_phy &&
                            ath_rc_priv->hw_maxretry_pktcnt < 255) {
                                ath_rc_priv->hw_maxretry_pktcnt++;
                        }

                }
        }
}

static void ath_rc_update_ht(struct ath_softc *sc,
                             struct ath_rate_priv *ath_rc_priv,
                             struct ieee80211_tx_info *tx_info,
                             int tx_rate, int xretries, int retries)
{
        u32 now_msec = jiffies_to_msecs(jiffies);
        int rate;
        u8 last_per;
        const struct ath_rate_table *rate_table = ath_rc_priv->rate_table;
        int size = ath_rc_priv->rate_table_size;

        if ((tx_rate < 0) || (tx_rate > rate_table->rate_cnt))
                return;

        last_per = ath_rc_priv->per[tx_rate];

        /* Update PER first */
        ath_rc_update_per(sc, rate_table, ath_rc_priv,
                          tx_info, tx_rate, xretries,
                          retries, now_msec);

        /*
         * If this rate looks bad (high PER) then stop using it for
         * a while (except if we are probing).
         */
        if (ath_rc_priv->per[tx_rate] >= 55 && tx_rate > 0 &&
            rate_table->info[tx_rate].ratekbps <=
            rate_table->info[ath_rc_priv->rate_max_phy].ratekbps) {
                ath_rc_get_lower_rix(ath_rc_priv, (u8)tx_rate,
                                     &ath_rc_priv->rate_max_phy);

                /* Don't probe for a little while. */
                ath_rc_priv->probe_time = now_msec;
        }

        /* Make sure the rates below this have lower PER */
        /* Monotonicity is kept only for rates below the current rate. */
        if (ath_rc_priv->per[tx_rate] < last_per) {
                for (rate = tx_rate - 1; rate >= 0; rate--) {

                        if (ath_rc_priv->per[rate] >
                            ath_rc_priv->per[rate+1]) {
                                ath_rc_priv->per[rate] =
                                        ath_rc_priv->per[rate+1];
                        }
                }
        }

        /* Maintain monotonicity for rates above the current rate */
        for (rate = tx_rate; rate < size - 1; rate++) {
                if (ath_rc_priv->per[rate+1] <
                    ath_rc_priv->per[rate])
                        ath_rc_priv->per[rate+1] =
                                ath_rc_priv->per[rate];
        }

        /* Every so often, we reduce the thresholds
         * and PER (different for CCK and OFDM). */
        if (now_msec - ath_rc_priv->per_down_time >=
            rate_table->probe_interval) {
                for (rate = 0; rate < size; rate++) {
                        ath_rc_priv->per[rate] =
                                7 * ath_rc_priv->per[rate] / 8;
                }

                ath_rc_priv->per_down_time = now_msec;
        }

        ath_debug_stat_retries(ath_rc_priv, tx_rate, xretries, retries,
                               ath_rc_priv->per[tx_rate]);

}

static void ath_rc_tx_status(struct ath_softc *sc,
                             struct ath_rate_priv *ath_rc_priv,
                             struct sk_buff *skb)
{
        struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
        struct ieee80211_tx_rate *rates = tx_info->status.rates;
        struct ieee80211_tx_rate *rate;
        int final_ts_idx = 0, xretries = 0, long_retry = 0;
        u8 flags;
        u32 i = 0, rix;

        for (i = 0; i < sc->hw->max_rates; i++) {
                rate = &tx_info->status.rates[i];
                if (rate->idx < 0 || !rate->count)
                        break;

                final_ts_idx = i;
                long_retry = rate->count - 1;
        }

        if (!(tx_info->flags & IEEE80211_TX_STAT_ACK))
                xretries = 1;

        /*
         * If the first rate is not the final index, there
         * are intermediate rate failures to be processed.
         */
        if (final_ts_idx != 0) {
                for (i = 0; i < final_ts_idx ; i++) {
                        if (rates[i].count != 0 && (rates[i].idx >= 0)) {
                                flags = rates[i].flags;

                                /* If HT40 and we have switched mode from
                                 * 40 to 20 => don't update */

                                if ((flags & IEEE80211_TX_RC_40_MHZ_WIDTH) &&
                                    !(ath_rc_priv->ht_cap & WLAN_RC_40_FLAG))
                                        return;

                                rix = ath_rc_get_rateindex(ath_rc_priv, &rates[i]);
                                ath_rc_update_ht(sc, ath_rc_priv, tx_info,
                                                 rix, xretries ? 1 : 2,
                                                 rates[i].count);
                        }
                }
        }

        flags = rates[final_ts_idx].flags;

        /* If HT40 and we have switched mode from 40 to 20 => don't update */
        if ((flags & IEEE80211_TX_RC_40_MHZ_WIDTH) &&
            !(ath_rc_priv->ht_cap & WLAN_RC_40_FLAG))
                return;

        rix = ath_rc_get_rateindex(ath_rc_priv, &rates[final_ts_idx]);
        ath_rc_update_ht(sc, ath_rc_priv, tx_info, rix, xretries, long_retry);
        ath_debug_stat_rc(ath_rc_priv, rix);
}

static const
struct ath_rate_table *ath_choose_rate_table(struct ath_softc *sc,
                                             enum ieee80211_band band,
                                             bool is_ht)
{
        switch(band) {
        case IEEE80211_BAND_2GHZ:
                if (is_ht)
                        return &ar5416_11ng_ratetable;
                return &ar5416_11g_ratetable;
        case IEEE80211_BAND_5GHZ:
                if (is_ht)
                        return &ar5416_11na_ratetable;
                return &ar5416_11a_ratetable;
        default:
                return NULL;
        }
}

static void ath_rc_init(struct ath_softc *sc,
                        struct ath_rate_priv *ath_rc_priv)
{
        const struct ath_rate_table *rate_table = ath_rc_priv->rate_table;
        struct ath_rateset *rateset = &ath_rc_priv->neg_rates;
        struct ath_common *common = ath9k_hw_common(sc->sc_ah);
        u8 i, j, k, hi = 0, hthi = 0;

        ath_rc_priv->rate_table_size = RATE_TABLE_SIZE;

        for (i = 0 ; i < ath_rc_priv->rate_table_size; i++) {
                ath_rc_priv->per[i] = 0;
                ath_rc_priv->valid_rate_index[i] = 0;
        }

        for (i = 0; i < WLAN_RC_PHY_MAX; i++) {
                for (j = 0; j < RATE_TABLE_SIZE; j++)
                        ath_rc_priv->valid_phy_rateidx[i][j] = 0;
                ath_rc_priv->valid_phy_ratecnt[i] = 0;
        }

        if (!rateset->rs_nrates) {
                hi = ath_rc_init_validrates(ath_rc_priv);
        } else {
                hi = ath_rc_setvalid_rates(ath_rc_priv, true);

                if (ath_rc_priv->ht_cap & WLAN_RC_HT_FLAG)
                        hthi = ath_rc_setvalid_rates(ath_rc_priv, false);

                hi = max(hi, hthi);
        }

        ath_rc_priv->rate_table_size = hi + 1;
        ath_rc_priv->rate_max_phy = 0;
        WARN_ON(ath_rc_priv->rate_table_size > RATE_TABLE_SIZE);

        for (i = 0, k = 0; i < WLAN_RC_PHY_MAX; i++) {
                for (j = 0; j < ath_rc_priv->valid_phy_ratecnt[i]; j++) {
                        ath_rc_priv->valid_rate_index[k++] =
                                ath_rc_priv->valid_phy_rateidx[i][j];
                }

                if (!ath_rc_valid_phyrate(i, rate_table->initial_ratemax, 1) ||
                    !ath_rc_priv->valid_phy_ratecnt[i])
                        continue;

                ath_rc_priv->rate_max_phy = ath_rc_priv->valid_phy_rateidx[i][j-1];
        }
        WARN_ON(ath_rc_priv->rate_table_size > RATE_TABLE_SIZE);
        WARN_ON(k > RATE_TABLE_SIZE);

        ath_rc_priv->max_valid_rate = k;
        ath_rc_sort_validrates(ath_rc_priv);
        ath_rc_priv->rate_max_phy = (k > 4) ?
                ath_rc_priv->valid_rate_index[k-4] :
                ath_rc_priv->valid_rate_index[k-1];

        ath_dbg(common, CONFIG, "RC Initialized with capabilities: 0x%x\n",
                ath_rc_priv->ht_cap);
}

static u8 ath_rc_build_ht_caps(struct ath_softc *sc, struct ieee80211_sta *sta)
{
        u8 caps = 0;

        if (sta->ht_cap.ht_supported) {
                caps = WLAN_RC_HT_FLAG;
                if (sta->ht_cap.mcs.rx_mask[1] && sta->ht_cap.mcs.rx_mask[2])
                        caps |= WLAN_RC_TS_FLAG | WLAN_RC_DS_FLAG;
                else if (sta->ht_cap.mcs.rx_mask[1])
                        caps |= WLAN_RC_DS_FLAG;
                if (sta->bandwidth >= IEEE80211_STA_RX_BW_40) {
                        caps |= WLAN_RC_40_FLAG;
                        if (sta->ht_cap.cap & IEEE80211_HT_CAP_SGI_40)
                                caps |= WLAN_RC_SGI_FLAG;
                } else {
                        if (sta->ht_cap.cap & IEEE80211_HT_CAP_SGI_20)
                                caps |= WLAN_RC_SGI_FLAG;
                }
        }

        return caps;
}

static bool ath_tx_aggr_check(struct ath_softc *sc, struct ieee80211_sta *sta,
                              u8 tidno)
{
        struct ath_node *an = (struct ath_node *)sta->drv_priv;
        struct ath_atx_tid *txtid;

        if (!sta->ht_cap.ht_supported)
                return false;

        txtid = ATH_AN_2_TID(an, tidno);
        return !txtid->active;
}


/***********************************/
/* mac80211 Rate Control callbacks */
/***********************************/

static void ath_tx_status(void *priv, struct ieee80211_supported_band *sband,
                          struct ieee80211_sta *sta, void *priv_sta,
                          struct sk_buff *skb)
{
        struct ath_softc *sc = priv;
        struct ath_rate_priv *ath_rc_priv = priv_sta;
        struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
        __le16 fc = hdr->frame_control;

        if (!priv_sta || !ieee80211_is_data(fc))
                return;

        /* This packet was aggregated but doesn't carry status info */
        if ((tx_info->flags & IEEE80211_TX_CTL_AMPDU) &&
            !(tx_info->flags & IEEE80211_TX_STAT_AMPDU))
                return;

        if (tx_info->flags & IEEE80211_TX_STAT_TX_FILTERED)
                return;

        ath_rc_tx_status(sc, ath_rc_priv, skb);

        /* Check if aggregation has to be enabled for this tid */
        if (conf_is_ht(&sc->hw->conf) &&
            !(skb->protocol == cpu_to_be16(ETH_P_PAE))) {
                if (ieee80211_is_data_qos(fc) &&
                    skb_get_queue_mapping(skb) != IEEE80211_AC_VO) {
                        u8 *qc, tid;

                        qc = ieee80211_get_qos_ctl(hdr);
                        tid = qc[0] & 0xf;

                        if(ath_tx_aggr_check(sc, sta, tid))
                                ieee80211_start_tx_ba_session(sta, tid, 0);
                }
        }
}

static void ath_rate_init(void *priv, struct ieee80211_supported_band *sband,
                          struct ieee80211_sta *sta, void *priv_sta)
{
        struct ath_softc *sc = priv;
        struct ath_common *common = ath9k_hw_common(sc->sc_ah);
        struct ath_rate_priv *ath_rc_priv = priv_sta;
        int i, j = 0;

        for (i = 0; i < sband->n_bitrates; i++) {
                if (sta->supp_rates[sband->band] & BIT(i)) {
                        ath_rc_priv->neg_rates.rs_rates[j]
                                = (sband->bitrates[i].bitrate * 2) / 10;
                        j++;
                }
        }
        ath_rc_priv->neg_rates.rs_nrates = j;

        if (sta->ht_cap.ht_supported) {
                for (i = 0, j = 0; i < 77; i++) {
                        if (sta->ht_cap.mcs.rx_mask[i/8] & (1<<(i%8)))
                                ath_rc_priv->neg_ht_rates.rs_rates[j++] = i;
                        if (j == ATH_RATE_MAX)
                                break;
                }
                ath_rc_priv->neg_ht_rates.rs_nrates = j;
        }

        ath_rc_priv->rate_table = ath_choose_rate_table(sc, sband->band,
                                                        sta->ht_cap.ht_supported);
        if (!ath_rc_priv->rate_table) {
                ath_err(common, "No rate table chosen\n");
                return;
        }

        ath_rc_priv->ht_cap = ath_rc_build_ht_caps(sc, sta);
        ath_rc_init(sc, priv_sta);
}

static void ath_rate_update(void *priv, struct ieee80211_supported_band *sband,
                            struct ieee80211_sta *sta, void *priv_sta,
                            u32 changed)
{
        struct ath_softc *sc = priv;
        struct ath_rate_priv *ath_rc_priv = priv_sta;

        if (changed & IEEE80211_RC_BW_CHANGED) {
                ath_rc_priv->ht_cap = ath_rc_build_ht_caps(sc, sta);
                ath_rc_init(sc, priv_sta);

                ath_dbg(ath9k_hw_common(sc->sc_ah), CONFIG,
                        "Operating HT Bandwidth changed to: %d\n",
                        cfg80211_get_chandef_type(&sc->hw->conf.chandef));
        }
}

#if defined(CONFIG_MAC80211_DEBUGFS) && defined(CONFIG_ATH9K_DEBUGFS)

void ath_debug_stat_rc(struct ath_rate_priv *rc, int final_rate)
{
        struct ath_rc_stats *stats;

        stats = &rc->rcstats[final_rate];
        stats->success++;
}

void ath_debug_stat_retries(struct ath_rate_priv *rc, int rix,
                            int xretries, int retries, u8 per)
{
        struct ath_rc_stats *stats = &rc->rcstats[rix];

        stats->xretries += xretries;
        stats->retries += retries;
        stats->per = per;
}

static ssize_t read_file_rcstat(struct file *file, char __user *user_buf,
                                size_t count, loff_t *ppos)
{
        struct ath_rate_priv *rc = file->private_data;
        char *buf;
        unsigned int len = 0, max;
        int rix;
        ssize_t retval;

        if (rc->rate_table == NULL)
                return 0;

        max = 80 + rc->rate_table_size * 1024 + 1;
        buf = kmalloc(max, GFP_KERNEL);
        if (buf == NULL)
                return -ENOMEM;

        len += sprintf(buf, "%6s %6s %6s "
                       "%10s %10s %10s %10s\n",
                       "HT", "MCS", "Rate",
                       "Success", "Retries", "XRetries", "PER");

        for (rix = 0; rix < rc->max_valid_rate; rix++) {
                u8 i = rc->valid_rate_index[rix];
                u32 ratekbps = rc->rate_table->info[i].ratekbps;
                struct ath_rc_stats *stats = &rc->rcstats[i];
                char mcs[5];
                char htmode[5];
                int used_mcs = 0, used_htmode = 0;

                if (WLAN_RC_PHY_HT(rc->rate_table->info[i].phy)) {
                        used_mcs = snprintf(mcs, 5, "%d",
                                rc->rate_table->info[i].ratecode);

                        if (WLAN_RC_PHY_40(rc->rate_table->info[i].phy))
                                used_htmode = snprintf(htmode, 5, "HT40");
                        else if (WLAN_RC_PHY_20(rc->rate_table->info[i].phy))
                                used_htmode = snprintf(htmode, 5, "HT20");
                        else
                                used_htmode = snprintf(htmode, 5, "????");
                }

                mcs[used_mcs] = '\0';
                htmode[used_htmode] = '\0';

                len += snprintf(buf + len, max - len,
                        "%6s %6s %3u.%d: "
                        "%10u %10u %10u %10u\n",
                        htmode,
                        mcs,
                        ratekbps / 1000,
                        (ratekbps % 1000) / 100,
                        stats->success,
                        stats->retries,
                        stats->xretries,
                        stats->per);
        }

        if (len > max)
                len = max;

        retval = simple_read_from_buffer(user_buf, count, ppos, buf, len);
        kfree(buf);
        return retval;
}

static const struct file_operations fops_rcstat = {
        .read = read_file_rcstat,
        .open = simple_open,
        .owner = THIS_MODULE
};

static void ath_rate_add_sta_debugfs(void *priv, void *priv_sta,
                                     struct dentry *dir)
{
        struct ath_rate_priv *rc = priv_sta;
        rc->debugfs_rcstats = debugfs_create_file("rc_stats", S_IRUGO,
                                                  dir, rc, &fops_rcstat);
}

static void ath_rate_remove_sta_debugfs(void *priv, void *priv_sta)
{
        struct ath_rate_priv *rc = priv_sta;
        debugfs_remove(rc->debugfs_rcstats);
}

#endif /* CONFIG_MAC80211_DEBUGFS && CONFIG_ATH9K_DEBUGFS */

static void *ath_rate_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir)
{
        return hw->priv;
}

static void ath_rate_free(void *priv)
{
        return;
}

static void *ath_rate_alloc_sta(void *priv, struct ieee80211_sta *sta, gfp_t gfp)
{
        return kzalloc(sizeof(struct ath_rate_priv), gfp);
}

static void ath_rate_free_sta(void *priv, struct ieee80211_sta *sta,
                              void *priv_sta)
{
        struct ath_rate_priv *rate_priv = priv_sta;
        kfree(rate_priv);
}

static struct rate_control_ops ath_rate_ops = {
        .module = NULL,
        .name = "ath9k_rate_control",
        .tx_status = ath_tx_status,
        .get_rate = ath_get_rate,
        .rate_init = ath_rate_init,
        .rate_update = ath_rate_update,
        .alloc = ath_rate_alloc,
        .free = ath_rate_free,
        .alloc_sta = ath_rate_alloc_sta,
        .free_sta = ath_rate_free_sta,

#if defined(CONFIG_MAC80211_DEBUGFS) && defined(CONFIG_ATH9K_DEBUGFS)
        .add_sta_debugfs = ath_rate_add_sta_debugfs,
        .remove_sta_debugfs = ath_rate_remove_sta_debugfs,
#endif
};

int ath_rate_control_register(void)
{
        return ieee80211_rate_control_register(&ath_rate_ops);
}

void ath_rate_control_unregister(void)
{
        ieee80211_rate_control_unregister(&ath_rate_ops);
}