1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * isl6421.h - driver for lnb supply and control ic ISL6421
4 *
5 * Copyright (C) 2006 Andrew de Quincey
6 * Copyright (C) 2006 Oliver Endriss
7 *
8 * the project's page is at https://linuxtv.org
9 */
10 #include <linux/delay.h>
11 #include <linux/errno.h>
12 #include <linux/init.h>
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/string.h>
16 #include <linux/slab.h>
17
18 #include <media/dvb_frontend.h>
19 #include "isl6421.h"
20
21 struct isl6421 {
22 u8 config;
23 u8 override_or;
24 u8 override_and;
25 struct i2c_adapter *i2c;
26 u8 i2c_addr;
27 bool is_off;
28 };
29
isl6421_set_voltage(struct dvb_frontend * fe,enum fe_sec_voltage voltage)30 static int isl6421_set_voltage(struct dvb_frontend *fe,
31 enum fe_sec_voltage voltage)
32 {
33 int ret;
34 u8 buf;
35 bool is_off;
36 struct isl6421 *isl6421 = (struct isl6421 *) fe->sec_priv;
37 struct i2c_msg msg[2] = {
38 {
39 .addr = isl6421->i2c_addr,
40 .flags = 0,
41 .buf = &isl6421->config,
42 .len = 1,
43 }, {
44 .addr = isl6421->i2c_addr,
45 .flags = I2C_M_RD,
46 .buf = &buf,
47 .len = 1,
48 }
49
50 };
51
52 isl6421->config &= ~(ISL6421_VSEL1 | ISL6421_EN1);
53
54 switch(voltage) {
55 case SEC_VOLTAGE_OFF:
56 is_off = true;
57 break;
58 case SEC_VOLTAGE_13:
59 is_off = false;
60 isl6421->config |= ISL6421_EN1;
61 break;
62 case SEC_VOLTAGE_18:
63 is_off = false;
64 isl6421->config |= (ISL6421_EN1 | ISL6421_VSEL1);
65 break;
66 default:
67 return -EINVAL;
68 }
69
70 /*
71 * If LNBf were not powered on, disable dynamic current limit, as,
72 * according with datasheet, highly capacitive load on the output may
73 * cause a difficult start-up.
74 */
75 if (isl6421->is_off && !is_off)
76 isl6421->config |= ISL6421_DCL;
77
78 isl6421->config |= isl6421->override_or;
79 isl6421->config &= isl6421->override_and;
80
81 ret = i2c_transfer(isl6421->i2c, msg, 2);
82 if (ret < 0)
83 return ret;
84 if (ret != 2)
85 return -EIO;
86
87 /* Store off status now in case future commands fail */
88 isl6421->is_off = is_off;
89
90 /* On overflow, the device will try again after 900 ms (typically) */
91 if (!is_off && (buf & ISL6421_OLF1))
92 msleep(1000);
93
94 /* Re-enable dynamic current limit */
95 if ((isl6421->config & ISL6421_DCL) &&
96 !(isl6421->override_or & ISL6421_DCL)) {
97 isl6421->config &= ~ISL6421_DCL;
98
99 ret = i2c_transfer(isl6421->i2c, msg, 2);
100 if (ret < 0)
101 return ret;
102 if (ret != 2)
103 return -EIO;
104 }
105
106 /* Check if overload flag is active. If so, disable power */
107 if (!is_off && (buf & ISL6421_OLF1)) {
108 isl6421->config &= ~(ISL6421_VSEL1 | ISL6421_EN1);
109 ret = i2c_transfer(isl6421->i2c, msg, 1);
110 if (ret < 0)
111 return ret;
112 if (ret != 1)
113 return -EIO;
114 isl6421->is_off = true;
115
116 dev_warn(&isl6421->i2c->dev,
117 "Overload current detected. disabling LNBf power\n");
118 return -EINVAL;
119 }
120
121 return 0;
122 }
123
isl6421_enable_high_lnb_voltage(struct dvb_frontend * fe,long arg)124 static int isl6421_enable_high_lnb_voltage(struct dvb_frontend *fe, long arg)
125 {
126 struct isl6421 *isl6421 = (struct isl6421 *) fe->sec_priv;
127 struct i2c_msg msg = { .addr = isl6421->i2c_addr, .flags = 0,
128 .buf = &isl6421->config,
129 .len = sizeof(isl6421->config) };
130
131 if (arg)
132 isl6421->config |= ISL6421_LLC1;
133 else
134 isl6421->config &= ~ISL6421_LLC1;
135
136 isl6421->config |= isl6421->override_or;
137 isl6421->config &= isl6421->override_and;
138
139 return (i2c_transfer(isl6421->i2c, &msg, 1) == 1) ? 0 : -EIO;
140 }
141
isl6421_set_tone(struct dvb_frontend * fe,enum fe_sec_tone_mode tone)142 static int isl6421_set_tone(struct dvb_frontend *fe,
143 enum fe_sec_tone_mode tone)
144 {
145 struct isl6421 *isl6421 = (struct isl6421 *) fe->sec_priv;
146 struct i2c_msg msg = { .addr = isl6421->i2c_addr, .flags = 0,
147 .buf = &isl6421->config,
148 .len = sizeof(isl6421->config) };
149
150 switch (tone) {
151 case SEC_TONE_ON:
152 isl6421->config |= ISL6421_ENT1;
153 break;
154 case SEC_TONE_OFF:
155 isl6421->config &= ~ISL6421_ENT1;
156 break;
157 default:
158 return -EINVAL;
159 }
160
161 isl6421->config |= isl6421->override_or;
162 isl6421->config &= isl6421->override_and;
163
164 return (i2c_transfer(isl6421->i2c, &msg, 1) == 1) ? 0 : -EIO;
165 }
166
isl6421_release(struct dvb_frontend * fe)167 static void isl6421_release(struct dvb_frontend *fe)
168 {
169 /* power off */
170 isl6421_set_voltage(fe, SEC_VOLTAGE_OFF);
171
172 /* free */
173 kfree(fe->sec_priv);
174 fe->sec_priv = NULL;
175 }
176
isl6421_attach(struct dvb_frontend * fe,struct i2c_adapter * i2c,u8 i2c_addr,u8 override_set,u8 override_clear,bool override_tone)177 struct dvb_frontend *isl6421_attach(struct dvb_frontend *fe, struct i2c_adapter *i2c, u8 i2c_addr,
178 u8 override_set, u8 override_clear, bool override_tone)
179 {
180 struct isl6421 *isl6421 = kmalloc(sizeof(struct isl6421), GFP_KERNEL);
181 if (!isl6421)
182 return NULL;
183
184 /* default configuration */
185 isl6421->config = ISL6421_ISEL1;
186 isl6421->i2c = i2c;
187 isl6421->i2c_addr = i2c_addr;
188 fe->sec_priv = isl6421;
189
190 /* bits which should be forced to '1' */
191 isl6421->override_or = override_set;
192
193 /* bits which should be forced to '0' */
194 isl6421->override_and = ~override_clear;
195
196 /* detect if it is present or not */
197 if (isl6421_set_voltage(fe, SEC_VOLTAGE_OFF)) {
198 kfree(isl6421);
199 fe->sec_priv = NULL;
200 return NULL;
201 }
202
203 isl6421->is_off = true;
204
205 /* install release callback */
206 fe->ops.release_sec = isl6421_release;
207
208 /* override frontend ops */
209 fe->ops.set_voltage = isl6421_set_voltage;
210 fe->ops.enable_high_lnb_voltage = isl6421_enable_high_lnb_voltage;
211 if (override_tone)
212 fe->ops.set_tone = isl6421_set_tone;
213
214 return fe;
215 }
216 EXPORT_SYMBOL(isl6421_attach);
217
218 MODULE_DESCRIPTION("Driver for lnb supply and control ic isl6421");
219 MODULE_AUTHOR("Andrew de Quincey & Oliver Endriss");
220 MODULE_LICENSE("GPL");
221