1 /*
2  * lnbh25.c
3  *
4  * Driver for LNB supply and control IC LNBH25
5  *
6  * Copyright (C) 2014 NetUP Inc.
7  * Copyright (C) 2014 Sergey Kozlov <serjk@netup.ru>
8  * Copyright (C) 2014 Abylay Ospan <aospan@netup.ru>
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License as published by
12  * the Free Software Foundation; either version 2 of the License, or
13  * (at your option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  * GNU General Public License for more details.
19  */
20 
21 #include <linux/module.h>
22 #include <linux/init.h>
23 #include <linux/string.h>
24 #include <linux/slab.h>
25 
26 #include "dvb_frontend.h"
27 #include "lnbh25.h"
28 
29 /**
30  * struct lnbh25_priv - LNBH25 driver private data
31  * @i2c:		pointer to the I2C adapter structure
32  * @i2c_address:	I2C address of LNBH25 SEC chip
33  * @config:		Registers configuration:
34  *			offset 0: 1st register address, always 0x02 (DATA1)
35  *			offset 1: DATA1 register value
36  *			offset 2: DATA2 register value
37  */
38 struct lnbh25_priv {
39 	struct i2c_adapter	*i2c;
40 	u8			i2c_address;
41 	u8			config[3];
42 };
43 
44 #define LNBH25_STATUS_OFL	0x1
45 #define LNBH25_STATUS_VMON	0x4
46 #define LNBH25_VSEL_13		0x03
47 #define LNBH25_VSEL_18		0x0a
48 
49 static int lnbh25_read_vmon(struct lnbh25_priv *priv)
50 {
51 	int i, ret;
52 	u8 addr = 0x00;
53 	u8 status[6];
54 	struct i2c_msg msg[2] = {
55 		{
56 			.addr = priv->i2c_address,
57 			.flags = 0,
58 			.len = 1,
59 			.buf = &addr
60 		}, {
61 			.addr = priv->i2c_address,
62 			.flags = I2C_M_RD,
63 			.len = sizeof(status),
64 			.buf = status
65 		}
66 	};
67 
68 	for (i = 0; i < 2; i++) {
69 		ret = i2c_transfer(priv->i2c, &msg[i], 1);
70 		if (ret >= 0 && ret != 1)
71 			ret = -EIO;
72 		if (ret < 0) {
73 			dev_dbg(&priv->i2c->dev,
74 				"%s(): I2C transfer %d failed (%d)\n",
75 				__func__, i, ret);
76 			return ret;
77 		}
78 	}
79 	dev_dbg(&priv->i2c->dev, "%s(): %*ph\n",
80 		__func__, (int) sizeof(status), status);
81 	if ((status[0] & (LNBH25_STATUS_OFL | LNBH25_STATUS_VMON)) != 0) {
82 		dev_err(&priv->i2c->dev,
83 			"%s(): voltage in failure state, status reg 0x%x\n",
84 			__func__, status[0]);
85 		return -EIO;
86 	}
87 	return 0;
88 }
89 
90 static int lnbh25_set_voltage(struct dvb_frontend *fe,
91 			      enum fe_sec_voltage voltage)
92 {
93 	int ret;
94 	u8 data1_reg;
95 	const char *vsel;
96 	struct lnbh25_priv *priv = fe->sec_priv;
97 	struct i2c_msg msg = {
98 		.addr = priv->i2c_address,
99 		.flags = 0,
100 		.len = sizeof(priv->config),
101 		.buf = priv->config
102 	};
103 
104 	switch (voltage) {
105 	case SEC_VOLTAGE_OFF:
106 		data1_reg = 0x00;
107 		vsel = "Off";
108 		break;
109 	case SEC_VOLTAGE_13:
110 		data1_reg = LNBH25_VSEL_13;
111 		vsel = "13V";
112 		break;
113 	case SEC_VOLTAGE_18:
114 		data1_reg = LNBH25_VSEL_18;
115 		vsel = "18V";
116 		break;
117 	default:
118 		return -EINVAL;
119 	}
120 	priv->config[1] = data1_reg;
121 	dev_dbg(&priv->i2c->dev,
122 		"%s(): %s, I2C 0x%x write [ %02x %02x %02x ]\n",
123 		__func__, vsel, priv->i2c_address,
124 		priv->config[0], priv->config[1], priv->config[2]);
125 	ret = i2c_transfer(priv->i2c, &msg, 1);
126 	if (ret >= 0 && ret != 1)
127 		ret = -EIO;
128 	if (ret < 0) {
129 		dev_err(&priv->i2c->dev, "%s(): I2C transfer error (%d)\n",
130 			__func__, ret);
131 		return ret;
132 	}
133 	if (voltage != SEC_VOLTAGE_OFF) {
134 		msleep(120);
135 		ret = lnbh25_read_vmon(priv);
136 	} else {
137 		msleep(20);
138 		ret = 0;
139 	}
140 	return ret;
141 }
142 
143 static void lnbh25_release(struct dvb_frontend *fe)
144 {
145 	struct lnbh25_priv *priv = fe->sec_priv;
146 
147 	dev_dbg(&priv->i2c->dev, "%s()\n", __func__);
148 	lnbh25_set_voltage(fe, SEC_VOLTAGE_OFF);
149 	kfree(fe->sec_priv);
150 	fe->sec_priv = NULL;
151 }
152 
153 struct dvb_frontend *lnbh25_attach(struct dvb_frontend *fe,
154 				   struct lnbh25_config *cfg,
155 				   struct i2c_adapter *i2c)
156 {
157 	struct lnbh25_priv *priv;
158 
159 	dev_dbg(&i2c->dev, "%s()\n", __func__);
160 	priv = kzalloc(sizeof(struct lnbh25_priv), GFP_KERNEL);
161 	if (!priv)
162 		return NULL;
163 	priv->i2c_address = (cfg->i2c_address >> 1);
164 	priv->i2c = i2c;
165 	priv->config[0] = 0x02;
166 	priv->config[1] = 0x00;
167 	priv->config[2] = cfg->data2_config;
168 	fe->sec_priv = priv;
169 	if (lnbh25_set_voltage(fe, SEC_VOLTAGE_OFF)) {
170 		dev_err(&i2c->dev,
171 			"%s(): no LNBH25 found at I2C addr 0x%02x\n",
172 			__func__, priv->i2c_address);
173 		kfree(priv);
174 		fe->sec_priv = NULL;
175 		return NULL;
176 	}
177 
178 	fe->ops.release_sec = lnbh25_release;
179 	fe->ops.set_voltage = lnbh25_set_voltage;
180 
181 	dev_info(&i2c->dev, "%s(): attached at I2C addr 0x%02x\n",
182 		__func__, priv->i2c_address);
183 	return fe;
184 }
185 EXPORT_SYMBOL(lnbh25_attach);
186 
187 MODULE_DESCRIPTION("ST LNBH25 driver");
188 MODULE_AUTHOR("info@netup.ru");
189 MODULE_LICENSE("GPL");
190