1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Support for Vishay VCNL3020 proximity sensor on i2c bus.
4 * Based on Vishay VCNL4000 driver code.
5 *
6 * TODO: interrupts.
7 */
8
9 #include <linux/module.h>
10 #include <linux/i2c.h>
11 #include <linux/err.h>
12 #include <linux/delay.h>
13 #include <linux/regmap.h>
14
15 #include <linux/iio/iio.h>
16 #include <linux/iio/sysfs.h>
17
18 #define VCNL3020_PROD_ID 0x21
19
20 #define VCNL_COMMAND 0x80 /* Command register */
21 #define VCNL_PROD_REV 0x81 /* Product ID and Revision ID */
22 #define VCNL_PROXIMITY_RATE 0x82 /* Rate of Proximity Measurement */
23 #define VCNL_LED_CURRENT 0x83 /* IR LED current for proximity mode */
24 #define VCNL_PS_RESULT_HI 0x87 /* Proximity result register, MSB */
25 #define VCNL_PS_RESULT_LO 0x88 /* Proximity result register, LSB */
26 #define VCNL_PS_ICR 0x89 /* Interrupt Control Register */
27 #define VCNL_PS_LO_THR_HI 0x8a /* High byte of low threshold value */
28 #define VCNL_PS_LO_THR_LO 0x8b /* Low byte of low threshold value */
29 #define VCNL_PS_HI_THR_HI 0x8c /* High byte of high threshold value */
30 #define VCNL_PS_HI_THR_LO 0x8d /* Low byte of high threshold value */
31 #define VCNL_ISR 0x8e /* Interrupt Status Register */
32 #define VCNL_PS_MOD_ADJ 0x8f /* Proximity Modulator Timing Adjustment */
33
34 /* Bit masks for COMMAND register */
35 #define VCNL_PS_RDY BIT(5) /* proximity data ready? */
36 #define VCNL_PS_OD BIT(3) /* start on-demand proximity
37 * measurement
38 */
39
40 #define VCNL_ON_DEMAND_TIMEOUT_US 100000
41 #define VCNL_POLL_US 20000
42
43 /**
44 * struct vcnl3020_data - vcnl3020 specific data.
45 * @regmap: device register map.
46 * @dev: vcnl3020 device.
47 * @rev: revision id.
48 * @lock: lock for protecting access to device hardware registers.
49 */
50 struct vcnl3020_data {
51 struct regmap *regmap;
52 struct device *dev;
53 u8 rev;
54 struct mutex lock;
55 };
56
57 /**
58 * struct vcnl3020_property - vcnl3020 property.
59 * @name: property name.
60 * @reg: i2c register offset.
61 * @conversion_func: conversion function.
62 */
63 struct vcnl3020_property {
64 const char *name;
65 u32 reg;
66 u32 (*conversion_func)(u32 *val);
67 };
68
microamp_to_reg(u32 * val)69 static u32 microamp_to_reg(u32 *val)
70 {
71 /*
72 * An example of conversion from uA to reg val:
73 * 200000 uA == 200 mA == 20
74 */
75 return *val /= 10000;
76 };
77
78 static struct vcnl3020_property vcnl3020_led_current_property = {
79 .name = "vishay,led-current-microamp",
80 .reg = VCNL_LED_CURRENT,
81 .conversion_func = microamp_to_reg,
82 };
83
vcnl3020_get_and_apply_property(struct vcnl3020_data * data,struct vcnl3020_property prop)84 static int vcnl3020_get_and_apply_property(struct vcnl3020_data *data,
85 struct vcnl3020_property prop)
86 {
87 int rc;
88 u32 val;
89
90 rc = device_property_read_u32(data->dev, prop.name, &val);
91 if (rc)
92 return 0;
93
94 if (prop.conversion_func)
95 prop.conversion_func(&val);
96
97 rc = regmap_write(data->regmap, prop.reg, val);
98 if (rc) {
99 dev_err(data->dev, "Error (%d) setting property (%s)\n",
100 rc, prop.name);
101 }
102
103 return rc;
104 }
105
vcnl3020_init(struct vcnl3020_data * data)106 static int vcnl3020_init(struct vcnl3020_data *data)
107 {
108 int rc;
109 unsigned int reg;
110
111 rc = regmap_read(data->regmap, VCNL_PROD_REV, ®);
112 if (rc) {
113 dev_err(data->dev,
114 "Error (%d) reading product revision\n", rc);
115 return rc;
116 }
117
118 if (reg != VCNL3020_PROD_ID) {
119 dev_err(data->dev,
120 "Product id (%x) did not match vcnl3020 (%x)\n", reg,
121 VCNL3020_PROD_ID);
122 return -ENODEV;
123 }
124
125 data->rev = reg;
126 mutex_init(&data->lock);
127
128 return vcnl3020_get_and_apply_property(data,
129 vcnl3020_led_current_property);
130 };
131
vcnl3020_measure_proximity(struct vcnl3020_data * data,int * val)132 static int vcnl3020_measure_proximity(struct vcnl3020_data *data, int *val)
133 {
134 int rc;
135 unsigned int reg;
136 __be16 res;
137
138 mutex_lock(&data->lock);
139
140 rc = regmap_write(data->regmap, VCNL_COMMAND, VCNL_PS_OD);
141 if (rc)
142 goto err_unlock;
143
144 /* wait for data to become ready */
145 rc = regmap_read_poll_timeout(data->regmap, VCNL_COMMAND, reg,
146 reg & VCNL_PS_RDY, VCNL_POLL_US,
147 VCNL_ON_DEMAND_TIMEOUT_US);
148 if (rc) {
149 dev_err(data->dev,
150 "Error (%d) reading vcnl3020 command register\n", rc);
151 goto err_unlock;
152 }
153
154 /* high & low result bytes read */
155 rc = regmap_bulk_read(data->regmap, VCNL_PS_RESULT_HI, &res,
156 sizeof(res));
157 if (rc)
158 goto err_unlock;
159
160 *val = be16_to_cpu(res);
161
162 err_unlock:
163 mutex_unlock(&data->lock);
164
165 return rc;
166 }
167
168 static const struct iio_chan_spec vcnl3020_channels[] = {
169 {
170 .type = IIO_PROXIMITY,
171 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
172 },
173 };
174
vcnl3020_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)175 static int vcnl3020_read_raw(struct iio_dev *indio_dev,
176 struct iio_chan_spec const *chan, int *val,
177 int *val2, long mask)
178 {
179 int rc;
180 struct vcnl3020_data *data = iio_priv(indio_dev);
181
182 switch (mask) {
183 case IIO_CHAN_INFO_RAW:
184 rc = vcnl3020_measure_proximity(data, val);
185 if (rc)
186 return rc;
187 return IIO_VAL_INT;
188 default:
189 return -EINVAL;
190 }
191 }
192
193 static const struct iio_info vcnl3020_info = {
194 .read_raw = vcnl3020_read_raw,
195 };
196
197 static const struct regmap_config vcnl3020_regmap_config = {
198 .reg_bits = 8,
199 .val_bits = 8,
200 .max_register = VCNL_PS_MOD_ADJ,
201 };
202
vcnl3020_probe(struct i2c_client * client)203 static int vcnl3020_probe(struct i2c_client *client)
204 {
205 struct vcnl3020_data *data;
206 struct iio_dev *indio_dev;
207 struct regmap *regmap;
208 int rc;
209
210 regmap = devm_regmap_init_i2c(client, &vcnl3020_regmap_config);
211 if (IS_ERR(regmap)) {
212 dev_err(&client->dev, "regmap_init failed\n");
213 return PTR_ERR(regmap);
214 }
215
216 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
217 if (!indio_dev)
218 return -ENOMEM;
219
220 data = iio_priv(indio_dev);
221 i2c_set_clientdata(client, indio_dev);
222 data->regmap = regmap;
223 data->dev = &client->dev;
224
225 rc = vcnl3020_init(data);
226 if (rc)
227 return rc;
228
229 indio_dev->info = &vcnl3020_info;
230 indio_dev->channels = vcnl3020_channels;
231 indio_dev->num_channels = ARRAY_SIZE(vcnl3020_channels);
232 indio_dev->name = "vcnl3020";
233 indio_dev->modes = INDIO_DIRECT_MODE;
234
235 return devm_iio_device_register(&client->dev, indio_dev);
236 }
237
238 static const struct of_device_id vcnl3020_of_match[] = {
239 {
240 .compatible = "vishay,vcnl3020",
241 },
242 {}
243 };
244 MODULE_DEVICE_TABLE(of, vcnl3020_of_match);
245
246 static struct i2c_driver vcnl3020_driver = {
247 .driver = {
248 .name = "vcnl3020",
249 .of_match_table = vcnl3020_of_match,
250 },
251 .probe_new = vcnl3020_probe,
252 };
253 module_i2c_driver(vcnl3020_driver);
254
255 MODULE_AUTHOR("Ivan Mikhaylov <i.mikhaylov@yadro.com>");
256 MODULE_DESCRIPTION("Vishay VCNL3020 proximity sensor driver");
257 MODULE_LICENSE("GPL");
258
