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
28static 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
45static 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
62static 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
76static 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
92static 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
110static 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
117static 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
162const 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