[PATCH] libertas: convert RSSI to a direct command
Besided the direct conversion of the CMD_802_11_RSSI command, this
patch also changes the following things:
* calls CMD_802_11_RSSI either asynchronously (in the background)
when main.c thinks the firmware is hosed and just want's to
get a command through
* calls CMD_802_11_RSSI synchronously when called to get wireless
statistics.
* don't do in-driver averaging anymore, this and the previous point
eliminates the need for any "struct lbs_private" values
* doesn't magically create a iwe.u.qual.level value in the adhoc
mode anymore. The old code access older SNR/NF values from
older RXPDs, but there that RXPDs could have been hours old.
Signed-off-by: Holger Schurig <hs4233@xxxxxxxxxxxxxxxxxxxx>
Index: wireless-testing/drivers/net/wireless/libertas/cmd.c
===================================================================
--- wireless-testing.orig/drivers/net/wireless/libertas/cmd.c 2008-03-18 11:38:41.000000000 +0100
+++ wireless-testing/drivers/net/wireless/libertas/cmd.c 2008-03-18 11:55:57.000000000 +0100
@@ -671,6 +671,44 @@ static int lbs_cmd_802_11_rate_adapt_rat
return 0;
}
+int lbs_get_rssi(struct lbs_private *priv, u16 *snr, u16 *nf)
+{
+ struct cmd_ds_802_11_rssi cmd;
+ struct cmd_ds_802_11_rssi_rsp rsp;
+ int ret;
+ u16 _snr, _nf;
+
+ lbs_deb_enter(LBS_DEB_CMD);
+
+ cmd.hdr.size = cpu_to_le16(sizeof(cmd));
+ cmd.avg_factor = cpu_to_le16(1);
+ rsp.hdr.size = cpu_to_le16(sizeof(rsp));
+
+ /* main.c might have called us just to un-break a hanging firmware */
+ if (!snr && !nf) {
+ lbs_cmd_async(priv, CMD_802_11_RSSI, &cmd.hdr, sizeof(cmd));
+ return 0;
+ }
+
+ ret = lbs_cmd(priv, CMD_802_11_RSSI,
+ &cmd, lbs_cmd_copyback, (unsigned long) &rsp);
+
+ if (!ret) {
+ _snr = le16_to_cpu(rsp.SNR);
+ _nf = le16_to_cpu(rsp.NF);
+ } else {
+ _snr = 0;
+ _nf = abs(MRVDRV_NF_DEFAULT_SCAN_VALUE);
+ }
+
+ if (*snr) *snr = _snr;
+ if (*nf) *nf = _nf;
+
+ lbs_deb_leave_args(LBS_DEB_CMD, "ret %d", ret);
+
+ return ret;
+}
+
/**
* @brief Get the current data rate
*
@@ -837,27 +875,6 @@ out:
return ret;
}
-static int lbs_cmd_802_11_rssi(struct lbs_private *priv,
- struct cmd_ds_command *cmd)
-{
-
- lbs_deb_enter(LBS_DEB_CMD);
- cmd->command = cpu_to_le16(CMD_802_11_RSSI);
- cmd->size = cpu_to_le16(sizeof(struct cmd_ds_802_11_rssi) + S_DS_GEN);
- cmd->params.rssi.N = cpu_to_le16(DEFAULT_BCN_AVG_FACTOR);
-
- /* reset Beacon SNR/NF/RSSI values */
- priv->SNR[TYPE_BEACON][TYPE_NOAVG] = 0;
- priv->SNR[TYPE_BEACON][TYPE_AVG] = 0;
- priv->NF[TYPE_BEACON][TYPE_NOAVG] = 0;
- priv->NF[TYPE_BEACON][TYPE_AVG] = 0;
- priv->RSSI[TYPE_BEACON][TYPE_NOAVG] = 0;
- priv->RSSI[TYPE_BEACON][TYPE_AVG] = 0;
-
- lbs_deb_leave(LBS_DEB_CMD);
- return 0;
-}
-
static int lbs_cmd_reg_access(struct lbs_private *priv,
struct cmd_ds_command *cmdptr,
u8 cmd_action, void *pdata_buf)
@@ -1413,10 +1430,6 @@ int lbs_prepare_and_send_command(struct
ret = lbs_cmd_80211_ad_hoc_join(priv, cmdptr, pdata_buf);
break;
- case CMD_802_11_RSSI:
- ret = lbs_cmd_802_11_rssi(priv, cmdptr);
- break;
-
case CMD_802_11_AD_HOC_STOP:
ret = lbs_cmd_80211_ad_hoc_stop(priv, cmdptr);
break;
Index: wireless-testing/drivers/net/wireless/libertas/cmdresp.c
===================================================================
--- wireless-testing.orig/drivers/net/wireless/libertas/cmdresp.c 2008-03-18 11:38:41.000000000 +0100
+++ wireless-testing/drivers/net/wireless/libertas/cmdresp.c 2008-03-18 11:52:42.000000000 +0100
@@ -51,15 +51,6 @@ void lbs_mac_event_disconnected(struct l
kfree_skb(priv->currenttxskb);
priv->currenttxskb = NULL;
priv->tx_pending_len = 0;
-
- /* reset SNR/NF/RSSI values */
- memset(priv->SNR, 0x00, sizeof(priv->SNR));
- memset(priv->NF, 0x00, sizeof(priv->NF));
- memset(priv->RSSI, 0x00, sizeof(priv->RSSI));
- memset(priv->rawSNR, 0x00, sizeof(priv->rawSNR));
- memset(priv->rawNF, 0x00, sizeof(priv->rawNF));
- priv->nextSNRNF = 0;
- priv->numSNRNF = 0;
priv->connect_status = LBS_DISCONNECTED;
/* Clear out associated SSID and BSSID since connection is
@@ -248,36 +239,6 @@ static int lbs_ret_802_11_rate_adapt_rat
return 0;
}
-static int lbs_ret_802_11_rssi(struct lbs_private *priv,
- struct cmd_ds_command *resp)
-{
- struct cmd_ds_802_11_rssi_rsp *rssirsp = &resp->params.rssirsp;
-
- lbs_deb_enter(LBS_DEB_CMD);
-
- /* store the non average value */
- priv->SNR[TYPE_BEACON][TYPE_NOAVG] = le16_to_cpu(rssirsp->SNR);
- priv->NF[TYPE_BEACON][TYPE_NOAVG] = le16_to_cpu(rssirsp->noisefloor);
-
- priv->SNR[TYPE_BEACON][TYPE_AVG] = le16_to_cpu(rssirsp->avgSNR);
- priv->NF[TYPE_BEACON][TYPE_AVG] = le16_to_cpu(rssirsp->avgnoisefloor);
-
- priv->RSSI[TYPE_BEACON][TYPE_NOAVG] =
- CAL_RSSI(priv->SNR[TYPE_BEACON][TYPE_NOAVG],
- priv->NF[TYPE_BEACON][TYPE_NOAVG]);
-
- priv->RSSI[TYPE_BEACON][TYPE_AVG] =
- CAL_RSSI(priv->SNR[TYPE_BEACON][TYPE_AVG] / AVG_SCALE,
- priv->NF[TYPE_BEACON][TYPE_AVG] / AVG_SCALE);
-
- lbs_deb_cmd("RSSI: beacon %d, avg %d\n",
- priv->RSSI[TYPE_BEACON][TYPE_NOAVG],
- priv->RSSI[TYPE_BEACON][TYPE_AVG]);
-
- lbs_deb_leave(LBS_DEB_CMD);
- return 0;
-}
-
static int lbs_ret_802_11_eeprom_access(struct lbs_private *priv,
struct cmd_ds_command *resp)
{
@@ -385,10 +346,6 @@ static inline int handle_cmd_response(st
ret = lbs_ret_802_11_rate_adapt_rateset(priv, resp);
break;
- case CMD_RET(CMD_802_11_RSSI):
- ret = lbs_ret_802_11_rssi(priv, resp);
- break;
-
case CMD_RET(CMD_802_11_MAC_ADDRESS):
ret = lbs_ret_802_11_mac_address(priv, resp);
break;
Index: wireless-testing/drivers/net/wireless/libertas/hostcmd.h
===================================================================
--- wireless-testing.orig/drivers/net/wireless/libertas/hostcmd.h 2008-03-18 11:38:41.000000000 +0100
+++ wireless-testing/drivers/net/wireless/libertas/hostcmd.h 2008-03-18 12:05:30.000000000 +0100
@@ -411,19 +411,21 @@ struct cmd_ds_802_11_rf_channel {
};
struct cmd_ds_802_11_rssi {
- /* weighting factor */
- __le16 N;
+ struct cmd_header hdr;
+ __le16 avg_factor;
__le16 reserved_0;
__le16 reserved_1;
__le16 reserved_2;
};
struct cmd_ds_802_11_rssi_rsp {
+ struct cmd_header hdr;
+
__le16 SNR;
- __le16 noisefloor;
+ __le16 NF;
__le16 avgSNR;
- __le16 avgnoisefloor;
+ __le16 avgNF;
};
struct cmd_ds_802_11_mac_address {
@@ -713,8 +715,6 @@ struct cmd_ds_command {
struct cmd_ds_802_11_rate_adapt_rateset rateset;
struct cmd_ds_mac_multicast_adr madr;
struct cmd_ds_802_11_ad_hoc_join adj;
- struct cmd_ds_802_11_rssi rssi;
- struct cmd_ds_802_11_rssi_rsp rssirsp;
struct cmd_ds_802_11_disassociate dassociate;
struct cmd_ds_802_11_mac_address macadd;
struct cmd_ds_mac_reg_access macreg;
Index: wireless-testing/drivers/net/wireless/libertas/assoc.c
===================================================================
--- wireless-testing.orig/drivers/net/wireless/libertas/assoc.c 2008-03-18 11:38:41.000000000 +0100
+++ wireless-testing/drivers/net/wireless/libertas/assoc.c 2008-03-18 11:47:16.000000000 +0100
@@ -621,9 +621,6 @@ void lbs_association_worker(struct work_
if (success) {
lbs_deb_assoc("associated to %s\n",
print_mac(mac, priv->curbssparams.bssid));
- lbs_prepare_and_send_command(priv,
- CMD_802_11_RSSI,
- 0, CMD_OPTION_WAITFORRSP, 0, NULL);
} else {
ret = -1;
}
Index: wireless-testing/drivers/net/wireless/libertas/main.c
===================================================================
--- wireless-testing.orig/drivers/net/wireless/libertas/main.c 2008-03-18 11:38:41.000000000 +0100
+++ wireless-testing/drivers/net/wireless/libertas/main.c 2008-03-18 11:47:16.000000000 +0100
@@ -487,8 +487,7 @@ static void lbs_tx_timeout(struct net_de
firmware has crapped itself -- rather than just a very
busy medium. So send a harmless command, and if/when
_that_ times out, we'll kick it in the head. */
- lbs_prepare_and_send_command(priv, CMD_802_11_RSSI, 0,
- 0, 0, NULL);
+ lbs_get_rssi(priv, NULL, NULL);
lbs_deb_leave(LBS_DEB_TX);
}
@@ -908,8 +907,7 @@ int lbs_resume(struct lbs_private *priv)
/* Firmware doesn't seem to give us RX packets any more
until we send it some command. Might as well update */
- lbs_prepare_and_send_command(priv, CMD_802_11_RSSI, 0,
- 0, 0, NULL);
+ lbs_get_rssi(priv, NULL, NULL);
netif_device_attach(priv->dev);
if (priv->mesh_dev)
Index: wireless-testing/drivers/net/wireless/libertas/scan.c
===================================================================
--- wireless-testing.orig/drivers/net/wireless/libertas/scan.c 2008-03-18 11:38:41.000000000 +0100
+++ wireless-testing/drivers/net/wireless/libertas/scan.c 2008-03-18 12:10:40.000000000 +0100
@@ -1194,25 +1194,7 @@ static inline char *lbs_translate_scan(s
if (iwe.u.qual.qual > 100)
iwe.u.qual.qual = 100;
- if (priv->NF[TYPE_BEACON][TYPE_NOAVG] == 0) {
- iwe.u.qual.noise = MRVDRV_NF_DEFAULT_SCAN_VALUE;
- } else {
- iwe.u.qual.noise = CAL_NF(priv->NF[TYPE_BEACON][TYPE_NOAVG]);
- }
-
- /* Locally created ad-hoc BSSs won't have beacons if this is the
- * only station in the adhoc network; so get signal strength
- * from receive statistics.
- */
- if ((priv->mode == IW_MODE_ADHOC) && priv->adhoccreate
- && !lbs_ssid_cmp(priv->curbssparams.ssid,
- priv->curbssparams.ssid_len,
- bss->ssid, bss->ssid_len)) {
- int snr, nf;
- snr = priv->SNR[TYPE_RXPD][TYPE_AVG] / AVG_SCALE;
- nf = priv->NF[TYPE_RXPD][TYPE_AVG] / AVG_SCALE;
- iwe.u.qual.level = CAL_RSSI(snr, nf);
- }
+ iwe.u.qual.noise = MRVDRV_NF_DEFAULT_SCAN_VALUE;
start = iwe_stream_add_event(start, stop, &iwe, IW_EV_QUAL_LEN);
/* Add encryption capability */
@@ -1369,11 +1351,6 @@ int lbs_get_scan(struct net_device *dev,
if (priv->scan_channel)
return -EAGAIN;
- /* Update RSSI if current BSS is a locally created ad-hoc BSS */
- if ((priv->mode == IW_MODE_ADHOC) && priv->adhoccreate)
- lbs_prepare_and_send_command(priv, CMD_802_11_RSSI, 0,
- CMD_OPTION_WAITFORRSP, 0, NULL);
-
mutex_lock(&priv->lock);
list_for_each_entry_safe (iter_bss, safe, &priv->network_list, list) {
char *next_ev;
Index: wireless-testing/drivers/net/wireless/libertas/cmd.h
===================================================================
--- wireless-testing.orig/drivers/net/wireless/libertas/cmd.h 2008-03-18 11:38:41.000000000 +0100
+++ wireless-testing/drivers/net/wireless/libertas/cmd.h 2008-03-18 11:47:16.000000000 +0100
@@ -34,6 +34,8 @@ int lbs_update_hw_spec(struct lbs_privat
int lbs_mesh_access(struct lbs_private *priv, uint16_t cmd_action,
struct cmd_ds_mesh_access *cmd);
+int lbs_get_rssi(struct lbs_private *priv, u16 *snr, u16 *nf);
+
int lbs_get_data_rate(struct lbs_private *priv);
int lbs_set_data_rate(struct lbs_private *priv, u8 rate);
Index: wireless-testing/drivers/net/wireless/libertas/dev.h
===================================================================
--- wireless-testing.orig/drivers/net/wireless/libertas/dev.h 2008-03-18 11:38:41.000000000 +0100
+++ wireless-testing/drivers/net/wireless/libertas/dev.h 2008-03-18 11:47:16.000000000 +0100
@@ -288,15 +288,6 @@ struct lbs_private {
u8 wpa_ie[MAX_WPA_IE_LEN];
u8 wpa_ie_len;
- /** Requested Signal Strength*/
- u16 SNR[MAX_TYPE_B][MAX_TYPE_AVG];
- u16 NF[MAX_TYPE_B][MAX_TYPE_AVG];
- u8 RSSI[MAX_TYPE_B][MAX_TYPE_AVG];
- u8 rawSNR[DEFAULT_DATA_AVG_FACTOR];
- u8 rawNF[DEFAULT_DATA_AVG_FACTOR];
- u16 nextSNRNF;
- u16 numSNRNF;
-
u8 radioon;
u32 preamble;
Index: wireless-testing/drivers/net/wireless/libertas/join.c
===================================================================
--- wireless-testing.orig/drivers/net/wireless/libertas/join.c 2008-03-18 11:38:41.000000000 +0100
+++ wireless-testing/drivers/net/wireless/libertas/join.c 2008-03-18 11:52:45.000000000 +0100
@@ -752,14 +752,6 @@ int lbs_ret_80211_associate(struct lbs_p
priv->curbssparams.ssid_len = bss->ssid_len;
memcpy(priv->curbssparams.bssid, bss->bssid, ETH_ALEN);
- priv->SNR[TYPE_RXPD][TYPE_AVG] = 0;
- priv->NF[TYPE_RXPD][TYPE_AVG] = 0;
-
- memset(priv->rawSNR, 0x00, sizeof(priv->rawSNR));
- memset(priv->rawNF, 0x00, sizeof(priv->rawNF));
- priv->nextSNRNF = 0;
- priv->numSNRNF = 0;
-
netif_carrier_on(priv->dev);
if (!priv->tx_pending_len)
netif_wake_queue(priv->dev);
Index: wireless-testing/drivers/net/wireless/libertas/wext.c
===================================================================
--- wireless-testing.orig/drivers/net/wireless/libertas/wext.c 2008-03-18 11:38:41.000000000 +0100
+++ wireless-testing/drivers/net/wireless/libertas/wext.c 2008-03-18 12:34:39.000000000 +0100
@@ -821,6 +821,7 @@ static struct iw_statistics *lbs_get_wir
u8 rssi;
u32 tx_retries;
struct cmd_ds_802_11_get_log log;
+ u16 snr, nf;
lbs_deb_enter(LBS_DEB_WEXT);
@@ -831,17 +832,11 @@ static struct iw_statistics *lbs_get_wir
(priv->mesh_connect_status != LBS_CONNECTED))
goto out;
- /* Quality by RSSI */
- priv->wstats.qual.level =
- CAL_RSSI(priv->SNR[TYPE_BEACON][TYPE_NOAVG],
- priv->NF[TYPE_BEACON][TYPE_NOAVG]);
+ lbs_get_rssi(priv, &snr, &nf);
- if (priv->NF[TYPE_BEACON][TYPE_NOAVG] == 0) {
- priv->wstats.qual.noise = MRVDRV_NF_DEFAULT_SCAN_VALUE;
- } else {
- priv->wstats.qual.noise =
- CAL_NF(priv->NF[TYPE_BEACON][TYPE_NOAVG]);
- }
+ /* Quality by RSSI */
+ priv->wstats.qual.level = CAL_RSSI(snr, nf);
+ priv->wstats.qual.noise = CAL_NF(nf);
lbs_deb_wext("signal level %#x\n", priv->wstats.qual.level);
lbs_deb_wext("noise %#x\n", priv->wstats.qual.noise);
@@ -893,9 +888,6 @@ static struct iw_statistics *lbs_get_wir
priv->wstats.qual.updated = IW_QUAL_ALL_UPDATED | IW_QUAL_DBM;
stats_valid = 1;
- /* update stats asynchronously for future calls */
- lbs_prepare_and_send_command(priv, CMD_802_11_RSSI, 0,
- 0, 0, NULL);
out:
if (!stats_valid) {
priv->wstats.miss.beacon = 0;
Index: wireless-testing/drivers/net/wireless/libertas/rx.c
===================================================================
--- wireless-testing.orig/drivers/net/wireless/libertas/rx.c 2008-03-18 11:38:41.000000000 +0100
+++ wireless-testing/drivers/net/wireless/libertas/rx.c 2008-03-18 12:37:04.000000000 +0100
@@ -39,99 +39,6 @@ static int process_rxed_802_11_packet(st
struct sk_buff *skb);
/**
- * @brief This function computes the avgSNR .
- *
- * @param priv A pointer to struct lbs_private structure
- * @return avgSNR
- */
-static u8 lbs_getavgsnr(struct lbs_private *priv)
-{
- u8 i;
- u16 temp = 0;
- if (priv->numSNRNF == 0)
- return 0;
- for (i = 0; i < priv->numSNRNF; i++)
- temp += priv->rawSNR[i];
- return (u8) (temp / priv->numSNRNF);
-
-}
-
-/**
- * @brief This function computes the AvgNF
- *
- * @param priv A pointer to struct lbs_private structure
- * @return AvgNF
- */
-static u8 lbs_getavgnf(struct lbs_private *priv)
-{
- u8 i;
- u16 temp = 0;
- if (priv->numSNRNF == 0)
- return 0;
- for (i = 0; i < priv->numSNRNF; i++)
- temp += priv->rawNF[i];
- return (u8) (temp / priv->numSNRNF);
-
-}
-
-/**
- * @brief This function save the raw SNR/NF to our internel buffer
- *
- * @param priv A pointer to struct lbs_private structure
- * @param prxpd A pointer to rxpd structure of received packet
- * @return n/a
- */
-static void lbs_save_rawSNRNF(struct lbs_private *priv, struct rxpd *p_rx_pd)
-{
- if (priv->numSNRNF < DEFAULT_DATA_AVG_FACTOR)
- priv->numSNRNF++;
- priv->rawSNR[priv->nextSNRNF] = p_rx_pd->snr;
- priv->rawNF[priv->nextSNRNF] = p_rx_pd->nf;
- priv->nextSNRNF++;
- if (priv->nextSNRNF >= DEFAULT_DATA_AVG_FACTOR)
- priv->nextSNRNF = 0;
- return;
-}
-
-/**
- * @brief This function computes the RSSI in received packet.
- *
- * @param priv A pointer to struct lbs_private structure
- * @param prxpd A pointer to rxpd structure of received packet
- * @return n/a
- */
-static void lbs_compute_rssi(struct lbs_private *priv, struct rxpd *p_rx_pd)
-{
-
- lbs_deb_enter(LBS_DEB_RX);
-
- lbs_deb_rx("rxpd: SNR %d, NF %d\n", p_rx_pd->snr, p_rx_pd->nf);
- lbs_deb_rx("before computing SNR: SNR-avg = %d, NF-avg = %d\n",
- priv->SNR[TYPE_RXPD][TYPE_AVG] / AVG_SCALE,
- priv->NF[TYPE_RXPD][TYPE_AVG] / AVG_SCALE);
-
- priv->SNR[TYPE_RXPD][TYPE_NOAVG] = p_rx_pd->snr;
- priv->NF[TYPE_RXPD][TYPE_NOAVG] = p_rx_pd->nf;
- lbs_save_rawSNRNF(priv, p_rx_pd);
-
- priv->SNR[TYPE_RXPD][TYPE_AVG] = lbs_getavgsnr(priv) * AVG_SCALE;
- priv->NF[TYPE_RXPD][TYPE_AVG] = lbs_getavgnf(priv) * AVG_SCALE;
- lbs_deb_rx("after computing SNR: SNR-avg = %d, NF-avg = %d\n",
- priv->SNR[TYPE_RXPD][TYPE_AVG] / AVG_SCALE,
- priv->NF[TYPE_RXPD][TYPE_AVG] / AVG_SCALE);
-
- priv->RSSI[TYPE_RXPD][TYPE_NOAVG] =
- CAL_RSSI(priv->SNR[TYPE_RXPD][TYPE_NOAVG],
- priv->NF[TYPE_RXPD][TYPE_NOAVG]);
-
- priv->RSSI[TYPE_RXPD][TYPE_AVG] =
- CAL_RSSI(priv->SNR[TYPE_RXPD][TYPE_AVG] / AVG_SCALE,
- priv->NF[TYPE_RXPD][TYPE_AVG] / AVG_SCALE);
-
- lbs_deb_leave(LBS_DEB_RX);
-}
-
-/**
* @brief This function processes received packet and forwards it
* to kernel/upper layer
*
@@ -240,8 +147,6 @@ int lbs_process_rxed_packet(struct lbs_p
if (priv->auto_rate)
priv->cur_rate = lbs_fw_index_to_data_rate(p_rx_pd->rx_rate);
- lbs_compute_rssi(priv, p_rx_pd);
-
lbs_deb_rx("rx data: size of actual packet %d\n", skb->len);
priv->stats.rx_bytes += skb->len;
priv->stats.rx_packets++;
@@ -359,7 +264,7 @@ static int process_rxed_802_11_packet(st
/* known values */
radiotap_hdr.rate = convert_mv_rate_to_radiotap(prxpd->rx_rate);
/* XXX must check no carryout */
- radiotap_hdr.antsignal = prxpd->snr + prxpd->nf;
+ radiotap_hdr.antsignal = CAL_RSSI(prxpd->snr, prxpd->nf);
radiotap_hdr.rx_flags = 0;
if (!(prxpd->status & cpu_to_le16(MRVDRV_RXPD_STATUS_OK)))
radiotap_hdr.rx_flags |= IEEE80211_RADIOTAP_F_RX_BADFCS;
@@ -386,8 +291,6 @@ static int process_rxed_802_11_packet(st
if (priv->auto_rate)
priv->cur_rate = lbs_fw_index_to_data_rate(prxpd->rx_rate);
- lbs_compute_rssi(priv, prxpd);
-
lbs_deb_rx("rx data: size of actual packet %d\n", skb->len);
priv->stats.rx_bytes += skb->len;
priv->stats.rx_packets++;
--
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