max2820.c

  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Radio tuning for Maxim max2820 on RTL8180
  4 *
  5 * Copyright 2007 Andrea Merello <andrea.merello@gmail.com>
  6 *
  7 * Code from the BSD driver and the rtl8181 project have been
  8 * very useful to understand certain things
  9 *
 10 * I want to thanks the Authors of such projects and the Ndiswrapper
 11 * project Authors.
 12 *
 13 * A special Big Thanks also is for all people who donated me cards,
 14 * making possible the creation of the original rtl8180 driver
 15 * from which this code is derived!
 16 */
 17
 18#include <linux/pci.h>
 19#include <linux/delay.h>
 20#include <net/mac80211.h>
 21
 22#include "rtl8180.h"
 23#include "max2820.h"
 24
 25static const u32 max2820_chan[] = {
 26	12, /* CH 1 */
 27	17,
 28	22,
 29	27,
 30	32,
 31	37,
 32	42,
 33	47,
 34	52,
 35	57,
 36	62,
 37	67,
 38	72,
 39	84, /* CH 14 */
 40};
 41
 42static void write_max2820(struct ieee80211_hw *dev, u8 addr, u32 data)
 43{
 44	struct rtl8180_priv *priv = dev->priv;
 45	u32 phy_config;
 46
 47	phy_config = 0x90 + (data & 0xf);
 48	phy_config <<= 16;
 49	phy_config += addr;
 50	phy_config <<= 8;
 51	phy_config += (data >> 4) & 0xff;
 52
 53	rtl818x_iowrite32(priv,
 54		(__le32 __iomem *) &priv->map->RFPinsOutput, phy_config);
 55
 56	msleep(1);
 57}
 58
 59static void max2820_write_phy_antenna(struct ieee80211_hw *dev, short chan)
 60{
 61	struct rtl8180_priv *priv = dev->priv;
 62	u8 ant;
 63
 64	ant = MAXIM_ANTENNA;
 65	if (priv->rfparam & RF_PARAM_ANTBDEFAULT)
 66		ant |= BB_ANTENNA_B;
 67	if (chan == 14)
 68		ant |= BB_ANTATTEN_CHAN14;
 69
 70	rtl8180_write_phy(dev, 0x10, ant);
 71}
 72
 73static u8 max2820_rf_calc_rssi(u8 agc, u8 sq)
 74{
 75	bool odd;
 76
 77	odd = !!(agc & 1);
 78
 79	agc >>= 1;
 80	if (odd)
 81		agc += 76;
 82	else
 83		agc += 66;
 84
 85	/* TODO: change addends above to avoid mult / div below */
 86	return 65 * agc / 100;
 87}
 88
 89static void max2820_rf_set_channel(struct ieee80211_hw *dev,
 90				   struct ieee80211_conf *conf)
 91{
 92	struct rtl8180_priv *priv = dev->priv;
 93	int channel = conf ?
 94		ieee80211_frequency_to_channel(conf->chandef.chan->center_freq) : 1;
 95	unsigned int chan_idx = channel - 1;
 96	u32 txpw = priv->channels[chan_idx].hw_value & 0xFF;
 97	u32 chan = max2820_chan[chan_idx];
 98
 99	/* While philips SA2400 drive the PA bias from
100	 * sa2400, for MAXIM we do this directly from BB */
101	rtl8180_write_phy(dev, 3, txpw);
102
103	max2820_write_phy_antenna(dev, channel);
104	write_max2820(dev, 3, chan);
105}
106
107static void max2820_rf_stop(struct ieee80211_hw *dev)
108{
109	rtl8180_write_phy(dev, 3, 0x8);
110	write_max2820(dev, 1, 0);
111}
112
113
114static void max2820_rf_init(struct ieee80211_hw *dev)
115{
116	struct rtl8180_priv *priv = dev->priv;
117
118	/* MAXIM from netbsd driver */
119	write_max2820(dev, 0, 0x007); /* test mode as indicated in datasheet */
120	write_max2820(dev, 1, 0x01e); /* enable register */
121	write_max2820(dev, 2, 0x001); /* synt register */
122
123	max2820_rf_set_channel(dev, NULL);
124
125	write_max2820(dev, 4, 0x313); /* rx register */
126
127	/* PA is driven directly by the BB, we keep the MAXIM bias
128	 * at the highest value in case that setting it to lower
129	 * values may introduce some further attenuation somewhere..
130	 */
131	write_max2820(dev, 5, 0x00f);
132
133	/* baseband configuration */
134	rtl8180_write_phy(dev, 0, 0x88); /* sys1       */
135	rtl8180_write_phy(dev, 3, 0x08); /* txagc      */
136	rtl8180_write_phy(dev, 4, 0xf8); /* lnadet     */
137	rtl8180_write_phy(dev, 5, 0x90); /* ifagcinit  */
138	rtl8180_write_phy(dev, 6, 0x1a); /* ifagclimit */
139	rtl8180_write_phy(dev, 7, 0x64); /* ifagcdet   */
140
141	max2820_write_phy_antenna(dev, 1);
142
143	rtl8180_write_phy(dev, 0x11, 0x88); /* trl */
144
145	if (rtl818x_ioread8(priv, &priv->map->CONFIG2) &
146	    RTL818X_CONFIG2_ANTENNA_DIV)
147		rtl8180_write_phy(dev, 0x12, 0xc7);
148	else
149		rtl8180_write_phy(dev, 0x12, 0x47);
150
151	rtl8180_write_phy(dev, 0x13, 0x9b);
152
153	rtl8180_write_phy(dev, 0x19, 0x0);  /* CHESTLIM */
154	rtl8180_write_phy(dev, 0x1a, 0x9f); /* CHSQLIM  */
155
156	max2820_rf_set_channel(dev, NULL);
157}
158
159const struct rtl818x_rf_ops max2820_rf_ops = {
160	.name		= "Maxim",
161	.init		= max2820_rf_init,
162	.stop		= max2820_rf_stop,
163	.set_chan	= max2820_rf_set_channel,
164	.calc_rssi	= max2820_rf_calc_rssi,
165};