1 /*
2  * Radio tuning for Maxim max2820 on RTL8180
3  *
4  * Copyright 2007 Andrea Merello <andrea.merello@gmail.com>
5  *
6  * Code from the BSD driver and the rtl8181 project have been
7  * very useful to understand certain things
8  *
9  * I want to thanks the Authors of such projects and the Ndiswrapper
10  * project Authors.
11  *
12  * A special Big Thanks also is for all people who donated me cards,
13  * making possible the creation of the original rtl8180 driver
14  * from which this code is derived!
15  *
16  * This program is free software; you can redistribute it and/or modify
17  * it under the terms of the GNU General Public License version 2 as
18  * published by the Free Software Foundation.
19  */
20 
21 #include <linux/pci.h>
22 #include <linux/delay.h>
23 #include <net/mac80211.h>
24 
25 #include "rtl8180.h"
26 #include "max2820.h"
27 
28 static const u32 max2820_chan[] = {
29 	12, /* CH 1 */
30 	17,
31 	22,
32 	27,
33 	32,
34 	37,
35 	42,
36 	47,
37 	52,
38 	57,
39 	62,
40 	67,
41 	72,
42 	84, /* CH 14 */
43 };
44 
45 static void write_max2820(struct ieee80211_hw *dev, u8 addr, u32 data)
46 {
47 	struct rtl8180_priv *priv = dev->priv;
48 	u32 phy_config;
49 
50 	phy_config = 0x90 + (data & 0xf);
51 	phy_config <<= 16;
52 	phy_config += addr;
53 	phy_config <<= 8;
54 	phy_config += (data >> 4) & 0xff;
55 
56 	rtl818x_iowrite32(priv,
57 		(__le32 __iomem *) &priv->map->RFPinsOutput, phy_config);
58 
59 	msleep(1);
60 }
61 
62 static void max2820_write_phy_antenna(struct ieee80211_hw *dev, short chan)
63 {
64 	struct rtl8180_priv *priv = dev->priv;
65 	u8 ant;
66 
67 	ant = MAXIM_ANTENNA;
68 	if (priv->rfparam & RF_PARAM_ANTBDEFAULT)
69 		ant |= BB_ANTENNA_B;
70 	if (chan == 14)
71 		ant |= BB_ANTATTEN_CHAN14;
72 
73 	rtl8180_write_phy(dev, 0x10, ant);
74 }
75 
76 static u8 max2820_rf_calc_rssi(u8 agc, u8 sq)
77 {
78 	bool odd;
79 
80 	odd = !!(agc & 1);
81 
82 	agc >>= 1;
83 	if (odd)
84 		agc += 76;
85 	else
86 		agc += 66;
87 
88 	/* TODO: change addends above to avoid mult / div below */
89 	return 65 * agc / 100;
90 }
91 
92 static void max2820_rf_set_channel(struct ieee80211_hw *dev,
93 				   struct ieee80211_conf *conf)
94 {
95 	struct rtl8180_priv *priv = dev->priv;
96 	int channel = conf ?
97 		ieee80211_frequency_to_channel(conf->chandef.chan->center_freq) : 1;
98 	unsigned int chan_idx = channel - 1;
99 	u32 txpw = priv->channels[chan_idx].hw_value & 0xFF;
100 	u32 chan = max2820_chan[chan_idx];
101 
102 	/* While philips SA2400 drive the PA bias from
103 	 * sa2400, for MAXIM we do this directly from BB */
104 	rtl8180_write_phy(dev, 3, txpw);
105 
106 	max2820_write_phy_antenna(dev, channel);
107 	write_max2820(dev, 3, chan);
108 }
109 
110 static void max2820_rf_stop(struct ieee80211_hw *dev)
111 {
112 	rtl8180_write_phy(dev, 3, 0x8);
113 	write_max2820(dev, 1, 0);
114 }
115 
116 
117 static void max2820_rf_init(struct ieee80211_hw *dev)
118 {
119 	struct rtl8180_priv *priv = dev->priv;
120 
121 	/* MAXIM from netbsd driver */
122 	write_max2820(dev, 0, 0x007); /* test mode as indicated in datasheet */
123 	write_max2820(dev, 1, 0x01e); /* enable register */
124 	write_max2820(dev, 2, 0x001); /* synt register */
125 
126 	max2820_rf_set_channel(dev, NULL);
127 
128 	write_max2820(dev, 4, 0x313); /* rx register */
129 
130 	/* PA is driven directly by the BB, we keep the MAXIM bias
131 	 * at the highest value in case that setting it to lower
132 	 * values may introduce some further attenuation somewhere..
133 	 */
134 	write_max2820(dev, 5, 0x00f);
135 
136 	/* baseband configuration */
137 	rtl8180_write_phy(dev, 0, 0x88); /* sys1       */
138 	rtl8180_write_phy(dev, 3, 0x08); /* txagc      */
139 	rtl8180_write_phy(dev, 4, 0xf8); /* lnadet     */
140 	rtl8180_write_phy(dev, 5, 0x90); /* ifagcinit  */
141 	rtl8180_write_phy(dev, 6, 0x1a); /* ifagclimit */
142 	rtl8180_write_phy(dev, 7, 0x64); /* ifagcdet   */
143 
144 	max2820_write_phy_antenna(dev, 1);
145 
146 	rtl8180_write_phy(dev, 0x11, 0x88); /* trl */
147 
148 	if (rtl818x_ioread8(priv, &priv->map->CONFIG2) &
149 	    RTL818X_CONFIG2_ANTENNA_DIV)
150 		rtl8180_write_phy(dev, 0x12, 0xc7);
151 	else
152 		rtl8180_write_phy(dev, 0x12, 0x47);
153 
154 	rtl8180_write_phy(dev, 0x13, 0x9b);
155 
156 	rtl8180_write_phy(dev, 0x19, 0x0);  /* CHESTLIM */
157 	rtl8180_write_phy(dev, 0x1a, 0x9f); /* CHSQLIM  */
158 
159 	max2820_rf_set_channel(dev, NULL);
160 }
161 
162 const struct rtl818x_rf_ops max2820_rf_ops = {
163 	.name		= "Maxim",
164 	.init		= max2820_rf_init,
165 	.stop		= max2820_rf_stop,
166 	.set_chan	= max2820_rf_set_channel,
167 	.calc_rssi	= max2820_rf_calc_rssi,
168 };
169