1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * ADE7854/58/68/78 Polyphase Multifunction Energy Metering IC Driver (SPI Bus)
4 *
5 * Copyright 2010 Analog Devices Inc.
6 */
7
8 #include <linux/device.h>
9 #include <linux/kernel.h>
10 #include <linux/spi/spi.h>
11 #include <linux/slab.h>
12 #include <linux/module.h>
13
14 #include <linux/iio/iio.h>
15 #include "ade7854.h"
16
ade7854_spi_write_reg(struct device * dev,u16 reg_address,u32 val,int bits)17 static int ade7854_spi_write_reg(struct device *dev,
18 u16 reg_address,
19 u32 val,
20 int bits)
21 {
22 int ret;
23 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
24 struct ade7854_state *st = iio_priv(indio_dev);
25 struct spi_transfer xfer = {
26 .tx_buf = st->tx,
27 .bits_per_word = 8,
28 .len = 4,
29 };
30
31 mutex_lock(&st->buf_lock);
32 st->tx[0] = ADE7854_WRITE_REG;
33 st->tx[1] = (reg_address >> 8) & 0xFF;
34 st->tx[2] = reg_address & 0xFF;
35 switch (bits) {
36 case 8:
37 st->tx[3] = val & 0xFF;
38 break;
39 case 16:
40 xfer.len = 5;
41 st->tx[3] = (val >> 8) & 0xFF;
42 st->tx[4] = val & 0xFF;
43 break;
44 case 24:
45 xfer.len = 6;
46 st->tx[3] = (val >> 16) & 0xFF;
47 st->tx[4] = (val >> 8) & 0xFF;
48 st->tx[5] = val & 0xFF;
49 break;
50 case 32:
51 xfer.len = 7;
52 st->tx[3] = (val >> 24) & 0xFF;
53 st->tx[4] = (val >> 16) & 0xFF;
54 st->tx[5] = (val >> 8) & 0xFF;
55 st->tx[6] = val & 0xFF;
56 break;
57 default:
58 ret = -EINVAL;
59 goto unlock;
60 }
61
62 ret = spi_sync_transfer(st->spi, &xfer, 1);
63 unlock:
64 mutex_unlock(&st->buf_lock);
65
66 return ret;
67 }
68
ade7854_spi_read_reg(struct device * dev,u16 reg_address,u32 * val,int bits)69 static int ade7854_spi_read_reg(struct device *dev,
70 u16 reg_address,
71 u32 *val,
72 int bits)
73 {
74 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
75 struct ade7854_state *st = iio_priv(indio_dev);
76 int ret;
77 struct spi_transfer xfers[] = {
78 {
79 .tx_buf = st->tx,
80 .bits_per_word = 8,
81 .len = 3,
82 }, {
83 .rx_buf = st->rx,
84 .bits_per_word = 8,
85 .len = bits,
86 }
87 };
88
89 mutex_lock(&st->buf_lock);
90
91 st->tx[0] = ADE7854_READ_REG;
92 st->tx[1] = (reg_address >> 8) & 0xFF;
93 st->tx[2] = reg_address & 0xFF;
94
95 ret = spi_sync_transfer(st->spi, xfers, ARRAY_SIZE(xfers));
96 if (ret < 0) {
97 dev_err(&st->spi->dev, "problem when reading register 0x%02X",
98 reg_address);
99 goto unlock;
100 }
101
102 switch (bits) {
103 case 8:
104 *val = st->rx[0];
105 break;
106 case 16:
107 *val = be16_to_cpup((const __be16 *)st->rx);
108 break;
109 case 24:
110 *val = (st->rx[0] << 16) | (st->rx[1] << 8) | st->rx[2];
111 break;
112 case 32:
113 *val = be32_to_cpup((const __be32 *)st->rx);
114 break;
115 }
116
117 unlock:
118 mutex_unlock(&st->buf_lock);
119 return ret;
120 }
121
ade7854_spi_probe(struct spi_device * spi)122 static int ade7854_spi_probe(struct spi_device *spi)
123 {
124 struct ade7854_state *st;
125 struct iio_dev *indio_dev;
126
127 indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
128 if (!indio_dev)
129 return -ENOMEM;
130 st = iio_priv(indio_dev);
131 spi_set_drvdata(spi, indio_dev);
132 st->read_reg = ade7854_spi_read_reg;
133 st->write_reg = ade7854_spi_write_reg;
134 st->irq = spi->irq;
135 st->spi = spi;
136
137 return ade7854_probe(indio_dev, &spi->dev);
138 }
139
140 static const struct spi_device_id ade7854_id[] = {
141 { "ade7854", 0 },
142 { "ade7858", 0 },
143 { "ade7868", 0 },
144 { "ade7878", 0 },
145 { }
146 };
147 MODULE_DEVICE_TABLE(spi, ade7854_id);
148
149 static struct spi_driver ade7854_driver = {
150 .driver = {
151 .name = "ade7854",
152 },
153 .probe = ade7854_spi_probe,
154 .id_table = ade7854_id,
155 };
156 module_spi_driver(ade7854_driver);
157
158 MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
159 MODULE_DESCRIPTION("Analog Devices ADE7854/58/68/78 SPI Driver");
160 MODULE_LICENSE("GPL v2");
161
