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8#include <linux/bits.h>
9#include <linux/device.h>
10#include <linux/hwmon.h>
11#include <linux/i2c.h>
12#include <linux/init.h>
13#include <linux/module.h>
14#include <linux/regulator/consumer.h>
15
16
17#define ADM1177_CMD_V_CONT BIT(0)
18#define ADM1177_CMD_I_CONT BIT(2)
19#define ADM1177_CMD_VRANGE BIT(4)
20
21
22#define ADM1177_REG_ALERT_TH 2
23
24#define ADM1177_BITS 12
25
26
27
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30
31
32
33
34struct adm1177_state {
35 struct i2c_client *client;
36 struct regulator *reg;
37 u32 r_sense_uohm;
38 u32 alert_threshold_ua;
39 bool vrange_high;
40};
41
42static int adm1177_read_raw(struct adm1177_state *st, u8 num, u8 *data)
43{
44 return i2c_master_recv(st->client, data, num);
45}
46
47static int adm1177_write_cmd(struct adm1177_state *st, u8 cmd)
48{
49 return i2c_smbus_write_byte(st->client, cmd);
50}
51
52static int adm1177_write_alert_thr(struct adm1177_state *st,
53 u32 alert_threshold_ua)
54{
55 u64 val;
56 int ret;
57
58 val = 0xFFULL * alert_threshold_ua * st->r_sense_uohm;
59 val = div_u64(val, 105840000U);
60 val = div_u64(val, 1000U);
61 if (val > 0xFF)
62 val = 0xFF;
63
64 ret = i2c_smbus_write_byte_data(st->client, ADM1177_REG_ALERT_TH,
65 val);
66 if (ret)
67 return ret;
68
69 st->alert_threshold_ua = alert_threshold_ua;
70 return 0;
71}
72
73static int adm1177_read(struct device *dev, enum hwmon_sensor_types type,
74 u32 attr, int channel, long *val)
75{
76 struct adm1177_state *st = dev_get_drvdata(dev);
77 u8 data[3];
78 long dummy;
79 int ret;
80
81 switch (type) {
82 case hwmon_curr:
83 switch (attr) {
84 case hwmon_curr_input:
85 ret = adm1177_read_raw(st, 3, data);
86 if (ret < 0)
87 return ret;
88 dummy = (data[1] << 4) | (data[2] & 0xF);
89
90
91
92
93 *val = div_u64((105840000ull * dummy),
94 4096 * st->r_sense_uohm);
95 return 0;
96 case hwmon_curr_max_alarm:
97 *val = st->alert_threshold_ua;
98 return 0;
99 default:
100 return -EOPNOTSUPP;
101 }
102 case hwmon_in:
103 ret = adm1177_read_raw(st, 3, data);
104 if (ret < 0)
105 return ret;
106 dummy = (data[0] << 4) | (data[2] >> 4);
107
108
109
110
111 if (st->vrange_high)
112 dummy *= 26350;
113 else
114 dummy *= 6650;
115
116 *val = DIV_ROUND_CLOSEST(dummy, 4096);
117 return 0;
118 default:
119 return -EOPNOTSUPP;
120 }
121}
122
123static int adm1177_write(struct device *dev, enum hwmon_sensor_types type,
124 u32 attr, int channel, long val)
125{
126 struct adm1177_state *st = dev_get_drvdata(dev);
127
128 switch (type) {
129 case hwmon_curr:
130 switch (attr) {
131 case hwmon_curr_max_alarm:
132 adm1177_write_alert_thr(st, val);
133 return 0;
134 default:
135 return -EOPNOTSUPP;
136 }
137 default:
138 return -EOPNOTSUPP;
139 }
140}
141
142static umode_t adm1177_is_visible(const void *data,
143 enum hwmon_sensor_types type,
144 u32 attr, int channel)
145{
146 const struct adm1177_state *st = data;
147
148 switch (type) {
149 case hwmon_in:
150 switch (attr) {
151 case hwmon_in_input:
152 return 0444;
153 }
154 break;
155 case hwmon_curr:
156 switch (attr) {
157 case hwmon_curr_input:
158 if (st->r_sense_uohm)
159 return 0444;
160 return 0;
161 case hwmon_curr_max_alarm:
162 if (st->r_sense_uohm)
163 return 0644;
164 return 0;
165 }
166 break;
167 default:
168 break;
169 }
170 return 0;
171}
172
173static const struct hwmon_channel_info *adm1177_info[] = {
174 HWMON_CHANNEL_INFO(curr,
175 HWMON_C_INPUT | HWMON_C_MAX_ALARM),
176 HWMON_CHANNEL_INFO(in,
177 HWMON_I_INPUT),
178 NULL
179};
180
181static const struct hwmon_ops adm1177_hwmon_ops = {
182 .is_visible = adm1177_is_visible,
183 .read = adm1177_read,
184 .write = adm1177_write,
185};
186
187static const struct hwmon_chip_info adm1177_chip_info = {
188 .ops = &adm1177_hwmon_ops,
189 .info = adm1177_info,
190};
191
192static void adm1177_remove(void *data)
193{
194 struct adm1177_state *st = data;
195
196 regulator_disable(st->reg);
197}
198
199static int adm1177_probe(struct i2c_client *client)
200{
201 struct device *dev = &client->dev;
202 struct device *hwmon_dev;
203 struct adm1177_state *st;
204 u32 alert_threshold_ua;
205 int ret;
206
207 st = devm_kzalloc(dev, sizeof(*st), GFP_KERNEL);
208 if (!st)
209 return -ENOMEM;
210
211 st->client = client;
212
213 st->reg = devm_regulator_get_optional(&client->dev, "vref");
214 if (IS_ERR(st->reg)) {
215 if (PTR_ERR(st->reg) == -EPROBE_DEFER)
216 return -EPROBE_DEFER;
217
218 st->reg = NULL;
219 } else {
220 ret = regulator_enable(st->reg);
221 if (ret)
222 return ret;
223 ret = devm_add_action_or_reset(&client->dev, adm1177_remove,
224 st);
225 if (ret)
226 return ret;
227 }
228
229 if (device_property_read_u32(dev, "shunt-resistor-micro-ohms",
230 &st->r_sense_uohm))
231 st->r_sense_uohm = 0;
232 if (device_property_read_u32(dev, "adi,shutdown-threshold-microamp",
233 &alert_threshold_ua)) {
234 if (st->r_sense_uohm)
235
236
237
238
239 alert_threshold_ua = div_u64(105840000000,
240 st->r_sense_uohm);
241 else
242 alert_threshold_ua = 0;
243 }
244 st->vrange_high = device_property_read_bool(dev,
245 "adi,vrange-high-enable");
246 if (alert_threshold_ua && st->r_sense_uohm)
247 adm1177_write_alert_thr(st, alert_threshold_ua);
248
249 ret = adm1177_write_cmd(st, ADM1177_CMD_V_CONT |
250 ADM1177_CMD_I_CONT |
251 (st->vrange_high ? 0 : ADM1177_CMD_VRANGE));
252 if (ret)
253 return ret;
254
255 hwmon_dev =
256 devm_hwmon_device_register_with_info(dev, client->name, st,
257 &adm1177_chip_info, NULL);
258 return PTR_ERR_OR_ZERO(hwmon_dev);
259}
260
261static const struct i2c_device_id adm1177_id[] = {
262 {"adm1177", 0},
263 {}
264};
265MODULE_DEVICE_TABLE(i2c, adm1177_id);
266
267static const struct of_device_id adm1177_dt_ids[] = {
268 { .compatible = "adi,adm1177" },
269 {},
270};
271MODULE_DEVICE_TABLE(of, adm1177_dt_ids);
272
273static struct i2c_driver adm1177_driver = {
274 .class = I2C_CLASS_HWMON,
275 .driver = {
276 .name = "adm1177",
277 .of_match_table = adm1177_dt_ids,
278 },
279 .probe_new = adm1177_probe,
280 .id_table = adm1177_id,
281};
282module_i2c_driver(adm1177_driver);
283
284MODULE_AUTHOR("Beniamin Bia <beniamin.bia@analog.com>");
285MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
286MODULE_DESCRIPTION("Analog Devices ADM1177 ADC driver");
287MODULE_LICENSE("GPL v2");
288
