1/*
2 * Radio tuning for Maxim max2820 on RTL8180
3 *
4 * Copyright 2007 Andrea Merello <andreamrl@tiscali.it>
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/init.h>
22#include <linux/pci.h>
23#include <linux/delay.h>
24#include <net/mac80211.h>
25
26#include "rtl8180.h"
27#include "max2820.h"
28
29static const u32 max2820_chan[] = {
30	12, /* CH 1 */
31	17,
32	22,
33	27,
34	32,
35	37,
36	42,
37	47,
38	52,
39	57,
40	62,
41	67,
42	72,
43	84, /* CH 14 */
44};
45
46static void write_max2820(struct ieee80211_hw *dev, u8 addr, u32 data)
47{
48	struct rtl8180_priv *priv = dev->priv;
49	u32 phy_config;
50
51	phy_config = 0x90 + (data & 0xf);
52	phy_config <<= 16;
53	phy_config += addr;
54	phy_config <<= 8;
55	phy_config += (data >> 4) & 0xff;
56
57	rtl818x_iowrite32(priv,
58		(__le32 __iomem *) &priv->map->RFPinsOutput, phy_config);
59
60	msleep(1);
61}
62
63static void max2820_write_phy_antenna(struct ieee80211_hw *dev, short chan)
64{
65	struct rtl8180_priv *priv = dev->priv;
66	u8 ant;
67
68	ant = MAXIM_ANTENNA;
69	if (priv->rfparam & RF_PARAM_ANTBDEFAULT)
70		ant |= BB_ANTENNA_B;
71	if (chan == 14)
72		ant |= BB_ANTATTEN_CHAN14;
73
74	rtl8180_write_phy(dev, 0x10, ant);
75}
76
77static u8 max2820_rf_calc_rssi(u8 agc, u8 sq)
78{
79	bool odd;
80
81	odd = !!(agc & 1);
82
83	agc >>= 1;
84	if (odd)
85		agc += 76;
86	else
87		agc += 66;
88
89	/* TODO: change addends above to avoid mult / div below */
90	return 65 * agc / 100;
91}
92
93static void max2820_rf_set_channel(struct ieee80211_hw *dev,
94				   struct ieee80211_conf *conf)
95{
96	struct rtl8180_priv *priv = dev->priv;
97	int channel = conf ?
98		ieee80211_frequency_to_channel(conf->channel->center_freq) : 1;
99	unsigned int chan_idx = channel - 1;
100	u32 txpw = priv->channels[chan_idx].hw_value & 0xFF;
101	u32 chan = max2820_chan[chan_idx];
102
103	/* While philips SA2400 drive the PA bias from
104	 * sa2400, for MAXIM we do this directly from BB */
105	rtl8180_write_phy(dev, 3, txpw);
106
107	max2820_write_phy_antenna(dev, channel);
108	write_max2820(dev, 3, chan);
109}
110
111static void max2820_rf_stop(struct ieee80211_hw *dev)
112{
113	rtl8180_write_phy(dev, 3, 0x8);
114	write_max2820(dev, 1, 0);
115}
116
117
118static void max2820_rf_init(struct ieee80211_hw *dev)
119{
120	struct rtl8180_priv *priv = dev->priv;
121
122	/* MAXIM from netbsd driver */
123	write_max2820(dev, 0, 0x007); /* test mode as indicated in datasheet */
124	write_max2820(dev, 1, 0x01e); /* enable register */
125	write_max2820(dev, 2, 0x001); /* synt register */
126
127	max2820_rf_set_channel(dev, NULL);
128
129	write_max2820(dev, 4, 0x313); /* rx register */
130
131	/* PA is driven directly by the BB, we keep the MAXIM bias
132	 * at the highest value in case that setting it to lower
133	 * values may introduce some further attenuation somewhere..
134	 */
135	write_max2820(dev, 5, 0x00f);
136
137	/* baseband configuration */
138	rtl8180_write_phy(dev, 0, 0x88); /* sys1       */
139	rtl8180_write_phy(dev, 3, 0x08); /* txagc      */
140	rtl8180_write_phy(dev, 4, 0xf8); /* lnadet     */
141	rtl8180_write_phy(dev, 5, 0x90); /* ifagcinit  */
142	rtl8180_write_phy(dev, 6, 0x1a); /* ifagclimit */
143	rtl8180_write_phy(dev, 7, 0x64); /* ifagcdet   */
144
145	max2820_write_phy_antenna(dev, 1);
146
147	rtl8180_write_phy(dev, 0x11, 0x88); /* trl */
148
149	if (rtl818x_ioread8(priv, &priv->map->CONFIG2) &
150	    RTL818X_CONFIG2_ANTENNA_DIV)
151		rtl8180_write_phy(dev, 0x12, 0xc7);
152	else
153		rtl8180_write_phy(dev, 0x12, 0x47);
154
155	rtl8180_write_phy(dev, 0x13, 0x9b);
156
157	rtl8180_write_phy(dev, 0x19, 0x0);  /* CHESTLIM */
158	rtl8180_write_phy(dev, 0x1a, 0x9f); /* CHSQLIM  */
159
160	max2820_rf_set_channel(dev, NULL);
161}
162
163const struct rtl818x_rf_ops max2820_rf_ops = {
164	.name		= "Maxim",
165	.init		= max2820_rf_init,
166	.stop		= max2820_rf_stop,
167	.set_chan	= max2820_rf_set_channel,
168	.calc_rssi	= max2820_rf_calc_rssi,
169};
170