1 /*
2 * ADE7854/58/68/78 Polyphase Multifunction Energy Metering IC Driver (SPI Bus)
3 *
4 * Copyright 2010 Analog Devices Inc.
5 *
6 * Licensed under the GPL-2 or later.
7 */
8
9 #include <linux/device.h>
10 #include <linux/kernel.h>
11 #include <linux/spi/spi.h>
12 #include <linux/slab.h>
13 #include <linux/module.h>
14
15 #include <linux/iio/iio.h>
16 #include "ade7854.h"
17
ade7854_spi_write_reg(struct device * dev,u16 reg_address,u32 val,int bits)18 static int ade7854_spi_write_reg(struct device *dev,
19 u16 reg_address,
20 u32 val,
21 int bits)
22 {
23 int ret;
24 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
25 struct ade7854_state *st = iio_priv(indio_dev);
26 struct spi_transfer xfer = {
27 .tx_buf = st->tx,
28 .bits_per_word = 8,
29 .len = 4,
30 };
31
32 mutex_lock(&st->buf_lock);
33 st->tx[0] = ADE7854_WRITE_REG;
34 st->tx[1] = (reg_address >> 8) & 0xFF;
35 st->tx[2] = reg_address & 0xFF;
36 switch (bits) {
37 case 8:
38 st->tx[3] = val & 0xFF;
39 break;
40 case 16:
41 xfer.len = 5;
42 st->tx[3] = (val >> 8) & 0xFF;
43 st->tx[4] = val & 0xFF;
44 break;
45 case 24:
46 xfer.len = 6;
47 st->tx[3] = (val >> 16) & 0xFF;
48 st->tx[4] = (val >> 8) & 0xFF;
49 st->tx[5] = val & 0xFF;
50 break;
51 case 32:
52 xfer.len = 7;
53 st->tx[3] = (val >> 24) & 0xFF;
54 st->tx[4] = (val >> 16) & 0xFF;
55 st->tx[5] = (val >> 8) & 0xFF;
56 st->tx[6] = val & 0xFF;
57 break;
58 default:
59 ret = -EINVAL;
60 goto unlock;
61 }
62
63 ret = spi_sync_transfer(st->spi, &xfer, 1);
64 unlock:
65 mutex_unlock(&st->buf_lock);
66
67 return ret;
68 }
69
ade7854_spi_read_reg(struct device * dev,u16 reg_address,u32 * val,int bits)70 static int ade7854_spi_read_reg(struct device *dev,
71 u16 reg_address,
72 u32 *val,
73 int bits)
74 {
75 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
76 struct ade7854_state *st = iio_priv(indio_dev);
77 int ret;
78 struct spi_transfer xfers[] = {
79 {
80 .tx_buf = st->tx,
81 .bits_per_word = 8,
82 .len = 3,
83 }, {
84 .rx_buf = st->rx,
85 .bits_per_word = 8,
86 .len = bits,
87 }
88 };
89
90 mutex_lock(&st->buf_lock);
91
92 st->tx[0] = ADE7854_READ_REG;
93 st->tx[1] = (reg_address >> 8) & 0xFF;
94 st->tx[2] = reg_address & 0xFF;
95
96 ret = spi_sync_transfer(st->spi, xfers, ARRAY_SIZE(xfers));
97 if (ret < 0) {
98 dev_err(&st->spi->dev, "problem when reading register 0x%02X",
99 reg_address);
100 goto unlock;
101 }
102
103 switch (bits) {
104 case 8:
105 *val = st->rx[0];
106 break;
107 case 16:
108 *val = be16_to_cpup((const __be16 *)st->rx);
109 break;
110 case 24:
111 *val = (st->rx[0] << 16) | (st->rx[1] << 8) | st->rx[2];
112 break;
113 case 32:
114 *val = be32_to_cpup((const __be32 *)st->rx);
115 break;
116 }
117
118 unlock:
119 mutex_unlock(&st->buf_lock);
120 return ret;
121 }
122
ade7854_spi_probe(struct spi_device * spi)123 static int ade7854_spi_probe(struct spi_device *spi)
124 {
125 struct ade7854_state *st;
126 struct iio_dev *indio_dev;
127
128 indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
129 if (!indio_dev)
130 return -ENOMEM;
131 st = iio_priv(indio_dev);
132 spi_set_drvdata(spi, indio_dev);
133 st->read_reg = ade7854_spi_read_reg;
134 st->write_reg = ade7854_spi_write_reg;
135 st->irq = spi->irq;
136 st->spi = spi;
137
138 return ade7854_probe(indio_dev, &spi->dev);
139 }
140
141 static const struct spi_device_id ade7854_id[] = {
142 { "ade7854", 0 },
143 { "ade7858", 0 },
144 { "ade7868", 0 },
145 { "ade7878", 0 },
146 { }
147 };
148 MODULE_DEVICE_TABLE(spi, ade7854_id);
149
150 static struct spi_driver ade7854_driver = {
151 .driver = {
152 .name = "ade7854",
153 },
154 .probe = ade7854_spi_probe,
155 .id_table = ade7854_id,
156 };
157 module_spi_driver(ade7854_driver);
158
159 MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
160 MODULE_DESCRIPTION("Analog Devices ADE7854/58/68/78 SPI Driver");
161 MODULE_LICENSE("GPL v2");
162
