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path: root/drivers/net/wireless/digiPiper/phy.c
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Diffstat (limited to 'drivers/net/wireless/digiPiper/phy.c')
-rw-r--r--drivers/net/wireless/digiPiper/phy.c269
1 files changed, 269 insertions, 0 deletions
diff --git a/drivers/net/wireless/digiPiper/phy.c b/drivers/net/wireless/digiPiper/phy.c
new file mode 100644
index 000000000000..5a6c53638e81
--- /dev/null
+++ b/drivers/net/wireless/digiPiper/phy.c
@@ -0,0 +1,269 @@
+/*
+ * Linux device driver for Digi's WiWave WLAN card
+ *
+ * Copyright © 2008 Digi International, Inc
+ *
+ * Author: Andres Salomon <dilinger@debian.org>
+ *
+ * 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.
+ */
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/module.h>
+#include <net/mac80211.h>
+
+#include "pipermain.h"
+#include "mac.h"
+#include "airoha.h"
+#include "phy.h"
+
+#define PHY_DEBUG (0)
+
+#if PHY_DEBUG
+static int dlevel = DVERBOSE;
+#define dprintk(level, fmt, arg...) if (level >= dlevel) \
+ printk(KERN_ERR PIPER_DRIVER_NAME \
+ ": %s - " fmt, __func__, ##arg)
+#else
+#define dprintk(level, fmt, arg...) do {} while (0)
+#endif
+
+#define NUMBER_OF_WORD32(x) ((x + 3) >> 2)
+
+static int is_ofdm_rate(int rate)
+{
+ return (rate % 3) == 0;
+}
+
+void phy_set_plcp(unsigned char *frame, unsigned length, struct ieee80211_rate *rate, int aes_len)
+{
+ int ofdm = is_ofdm_rate(rate->bitrate);
+ int plcp_len = length + FCS_LEN + aes_len;
+ struct tx_frame_hdr *hdr;
+
+ if (ofdm) {
+ /* OFDM header */
+ struct ofdm_hdr *ofdm;
+
+ ofdm = (struct ofdm_hdr *) &frame[sizeof(struct tx_frame_hdr)];
+ memset(ofdm, 0, sizeof(*ofdm));
+ ofdm->rate = rate->hw_value;
+ ofdm->length = cpu_to_le16(plcp_len);
+ } else {
+ /* PSK/CCK header */
+ struct psk_cck_hdr *pskcck;
+ int us_len;
+
+ pskcck = (struct psk_cck_hdr *) &frame[sizeof(struct tx_frame_hdr)];
+ pskcck->signal = rate->bitrate;
+ pskcck->service = PLCP_SERVICE_LOCKED;
+
+ /* convert length from bytes to usecs */
+ switch (rate->bitrate) {
+ case 10:
+ us_len = plcp_len * 8;
+ break;
+ case 20:
+ us_len = plcp_len * 4;
+ break;
+ case 55:
+ us_len = (16 * plcp_len + 10) / 11;
+ break;
+ case 110:
+ us_len = (8 * plcp_len + 10) / 11;
+
+ /* set length extension bit if needed */
+ dprintk(DALL, "us_len = %d, plcp_len = %d, (11 * us_len) = %d, \
+ (11 * us_len) / 8 = %d\n", us_len, plcp_len,
+ (11 * us_len), (11 * us_len) / 8);
+
+ if ((11 * us_len) / 8 > plcp_len) {
+ pskcck->service |= PLCP_SERVICE_LENEXT;
+ dprintk(DALL, "Set PLCP_SERVICE_LENEXT, \
+ pskcck->service = 0x%4.4X\n", pskcck->service);
+ } else {
+ dprintk(DALL, "Did not set PLCP_SERVICE_LENEXT, \
+ pskcck->service = 0x%4.4X\n", pskcck->service);
+ }
+ break;
+ default:
+ digi_dbg("rate = %p, rate->bitrate%d\n", rate, rate->bitrate);
+ WARN_ON(1);
+ us_len = 0;
+ }
+
+ pskcck->length = cpu_to_le16(us_len);
+
+ dprintk(DALL, "pskcck .length = %d, signal = %d, service = %d\n",
+ pskcck->length, pskcck->signal, pskcck->service);
+ dprintk(DALL, "rate->bitrate=%x (@%dM), pckcck->length=%d\n",
+ rate->bitrate, rate->bitrate/10, pskcck->length);
+ }
+
+ hdr = (struct tx_frame_hdr *) frame;
+ hdr->pad = 0;
+ hdr->length = NUMBER_OF_WORD32((length + aes_len + TX_HEADER_LENGTH));
+ hdr->modulation_type = ofdm ? MOD_TYPE_OFDM : MOD_TYPE_PSKCCK;
+
+ dprintk(DVVERBOSE, "frame hdr .length = %d, .modulation_type = %d\n",
+ hdr->length, hdr->modulation_type);
+
+ dprintk(DVERBOSE, "TX: %d byte %s packet @ %dmbit\n", length,
+ ofdm ? "OFDM" : "PSK/CCK", rate->bitrate/10);
+}
+EXPORT_SYMBOL_GPL(phy_set_plcp);
+
+
+static int get_signal(struct rx_frame_hdr *hdr, enum ieee80211_band rf_band, int transceiver)
+{
+ int gain;
+ int signal;
+
+ if (transceiver == RF_AIROHA_2236) {
+ const u8 lnaTable_al2236[] =
+ {
+ 0, 0, 20, 36
+ };
+
+ // Map high gain values to dbm
+ const signed char gainTable_al2236[] =
+ {
+ -85, -85, -88, -88, -92
+ };
+ // Convert received signal strength to dbm
+ gain = lnaTable_al2236[hdr->rssi_low_noise_amp] + 2*hdr->rssi_variable_gain_attenuator;
+ if (gain > 92)
+ signal = -96;
+ else if (gain > 87)
+ signal = gainTable_al2236[gain - 88];
+ else
+ signal = 4 - gain;
+ } else {
+ static const u8 lnaTable_al7230_24ghz[] =
+ {
+ 0, 0, 18, 42
+ };
+ static const u8 lnaTable_al7230_50ghz[] =
+ {
+ 0, 0, 17, 37
+ };
+ /* Convert received signal strength to dbm for RF_AIROHA_7230 */
+ if (rf_band == IEEE80211_BAND_2GHZ) {
+ gain = lnaTable_al7230_24ghz[hdr->rssi_low_noise_amp] + 2*hdr->rssi_variable_gain_attenuator;
+ signal = 2 - gain;
+ } else {
+ gain = lnaTable_al7230_50ghz[hdr->rssi_low_noise_amp] + 2*hdr->rssi_variable_gain_attenuator;
+ signal = -5 - gain;
+ }
+ }
+
+ return signal;
+}
+
+
+
+
+/* FIXME, following limtis should depend on the platform */
+#define PIPER_MAX_SIGNAL_DBM (-30)
+#define PIPER_MIN_SIGNAL_DBM (-90)
+
+static int calculate_link_quality(int signal)
+{
+ int quality;
+
+ if (signal < PIPER_MIN_SIGNAL_DBM)
+ quality = 0;
+ else if (signal > PIPER_MAX_SIGNAL_DBM)
+ quality = 100;
+ else
+ quality = (signal - PIPER_MIN_SIGNAL_DBM) * 100 /
+ (PIPER_MAX_SIGNAL_DBM - PIPER_MIN_SIGNAL_DBM);
+
+ dprintk(DVERBOSE, "signal: %d, quality: %d/100\n", signal, quality);
+
+ return quality;
+}
+
+unsigned int phy_determine_rssi(struct rx_frame_hdr *hdr)
+{
+ return (hdr->rssi_low_noise_amp << 5) | hdr->rssi_variable_gain_attenuator;
+}
+EXPORT_SYMBOL_GPL(phy_determine_rssi);
+
+
+
+void phy_process_plcp(struct piper_priv *piper, struct rx_frame_hdr *hdr,
+ struct ieee80211_rx_status *status, unsigned int *length)
+{
+ unsigned rate, i;
+ struct digi_rf_ops *rf = piper->rf;
+
+ memset(status, 0, sizeof(*status));
+ status->band = piper->rf->getBand(piper->channel);
+ status->signal = get_signal(hdr, status->band, piper->pdata->rf_transceiver);
+ status->antenna = hdr->antenna;
+ status->freq = piper->rf->getFrequency(piper->channel);
+ status->qual = calculate_link_quality(status->signal);
+
+ if (hdr->modulation_type == MOD_TYPE_OFDM) {
+ /* OFDM */
+ struct ofdm_hdr *ofdm = &hdr->mod.ofdm;
+ const int ofdm_rate[] = {
+ 480, 240, 120, 60, 540, 360, 180, 90
+ };
+
+ rate = ofdm_rate[ofdm->rate & 0x7];
+ *length = le16_to_cpu(ofdm->length);
+ dprintk(DVVERBOSE, "%d byte OFDM packet @ %dmbit\n",
+ *length, rate/10);
+ } else {
+ /* PSK/CCK */
+ struct psk_cck_hdr *pskcck = &hdr->mod.psk;
+
+ rate = pskcck->signal;
+
+ *length = le16_to_cpu(pskcck->length);
+ switch (rate) {
+ case 10:
+ *length /= 8;
+ break;
+ case 20:
+ *length /= 4;
+ break;
+ case 55:
+ *length = (11 * (*length)) / 16;
+ break;
+ case 110:
+ *length = (11 * (*length)) / 8;
+ if (pskcck->service & PLCP_SERVICE_LENEXT)
+ (*length)--;
+ break;
+ default:
+ /* WARN_ON(1); This happens to often for us to generate that long error message */
+ *length = 0;
+ }
+
+ dprintk(DVVERBOSE, "%d byte PSK/CCK packet @ %dmbit\n",
+ *length, rate/10);
+ }
+
+ /* match rate with the list of bitrates that we supplied the stack */
+ for (i = 0; i < rf->bands[status->band].n_bitrates; i++) {
+ if (rf->bands[status->band].bitrates[i].bitrate == rate)
+ break;
+ }
+
+ if (i != rf->bands[status->band].n_bitrates)
+ status->rate_idx = i;
+ else {
+ *length = 0;
+ digi_dbg(PIPER_DRIVER_NAME
+ ": couldn't find bitrate index for %d?\n",
+ rate);
+ status->flag |= RX_FLAG_FAILED_PLCP_CRC;
+ return;
+ }
+}
+EXPORT_SYMBOL_GPL(phy_process_plcp);
generated by cgit v1.2.3 (git 2.0.4) at 2024-05-28 12:02:52 +0000