This source file includes following definitions.
- z188_iio_read_raw
- men_z188_config_channels
- men_z188_probe
- men_z188_remove
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9 #include <linux/kernel.h>
10 #include <linux/module.h>
11 #include <linux/mcb.h>
12 #include <linux/io.h>
13 #include <linux/iio/iio.h>
14
15 #define Z188_ADC_MAX_CHAN 8
16 #define Z188_ADC_GAIN 0x0700000
17 #define Z188_MODE_VOLTAGE BIT(27)
18 #define Z188_CFG_AUTO 0x1
19 #define Z188_CTRL_REG 0x40
20
21 #define ADC_DATA(x) (((x) >> 2) & 0x7ffffc)
22 #define ADC_OVR(x) ((x) & 0x1)
23
24 struct z188_adc {
25 struct resource *mem;
26 void __iomem *base;
27 };
28
29 #define Z188_ADC_CHANNEL(idx) { \
30 .type = IIO_VOLTAGE, \
31 .indexed = 1, \
32 .channel = (idx), \
33 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
34 }
35
36 static const struct iio_chan_spec z188_adc_iio_channels[] = {
37 Z188_ADC_CHANNEL(0),
38 Z188_ADC_CHANNEL(1),
39 Z188_ADC_CHANNEL(2),
40 Z188_ADC_CHANNEL(3),
41 Z188_ADC_CHANNEL(4),
42 Z188_ADC_CHANNEL(5),
43 Z188_ADC_CHANNEL(6),
44 Z188_ADC_CHANNEL(7),
45 };
46
47 static int z188_iio_read_raw(struct iio_dev *iio_dev,
48 struct iio_chan_spec const *chan,
49 int *val,
50 int *val2,
51 long info)
52 {
53 struct z188_adc *adc = iio_priv(iio_dev);
54 int ret;
55 u16 tmp;
56
57 switch (info) {
58 case IIO_CHAN_INFO_RAW:
59 tmp = readw(adc->base + chan->channel * 4);
60
61 if (ADC_OVR(tmp)) {
62 dev_info(&iio_dev->dev,
63 "Oversampling error on ADC channel %d\n",
64 chan->channel);
65 return -EIO;
66 }
67 *val = ADC_DATA(tmp);
68 ret = IIO_VAL_INT;
69 break;
70 default:
71 ret = -EINVAL;
72 break;
73 }
74
75 return ret;
76 }
77
78 static const struct iio_info z188_adc_info = {
79 .read_raw = &z188_iio_read_raw,
80 };
81
82 static void men_z188_config_channels(void __iomem *addr)
83 {
84 int i;
85 u32 cfg;
86 u32 ctl;
87
88 ctl = readl(addr + Z188_CTRL_REG);
89 ctl |= Z188_CFG_AUTO;
90 writel(ctl, addr + Z188_CTRL_REG);
91
92 for (i = 0; i < Z188_ADC_MAX_CHAN; i++) {
93 cfg = readl(addr + i);
94 cfg &= ~Z188_ADC_GAIN;
95 cfg |= Z188_MODE_VOLTAGE;
96 writel(cfg, addr + i);
97 }
98 }
99
100 static int men_z188_probe(struct mcb_device *dev,
101 const struct mcb_device_id *id)
102 {
103 struct z188_adc *adc;
104 struct iio_dev *indio_dev;
105 struct resource *mem;
106
107 indio_dev = devm_iio_device_alloc(&dev->dev, sizeof(struct z188_adc));
108 if (!indio_dev)
109 return -ENOMEM;
110
111 adc = iio_priv(indio_dev);
112 indio_dev->name = "z188-adc";
113 indio_dev->dev.parent = &dev->dev;
114 indio_dev->info = &z188_adc_info;
115 indio_dev->modes = INDIO_DIRECT_MODE;
116 indio_dev->channels = z188_adc_iio_channels;
117 indio_dev->num_channels = ARRAY_SIZE(z188_adc_iio_channels);
118
119 mem = mcb_request_mem(dev, "z188-adc");
120 if (IS_ERR(mem))
121 return PTR_ERR(mem);
122
123 adc->base = ioremap(mem->start, resource_size(mem));
124 if (adc->base == NULL)
125 goto err;
126
127 men_z188_config_channels(adc->base);
128
129 adc->mem = mem;
130 mcb_set_drvdata(dev, indio_dev);
131
132 return iio_device_register(indio_dev);
133
134 err:
135 mcb_release_mem(mem);
136 return -ENXIO;
137 }
138
139 static void men_z188_remove(struct mcb_device *dev)
140 {
141 struct iio_dev *indio_dev = mcb_get_drvdata(dev);
142 struct z188_adc *adc = iio_priv(indio_dev);
143
144 iio_device_unregister(indio_dev);
145 iounmap(adc->base);
146 mcb_release_mem(adc->mem);
147 }
148
149 static const struct mcb_device_id men_z188_ids[] = {
150 { .device = 0xbc },
151 { }
152 };
153 MODULE_DEVICE_TABLE(mcb, men_z188_ids);
154
155 static struct mcb_driver men_z188_driver = {
156 .driver = {
157 .name = "z188-adc",
158 .owner = THIS_MODULE,
159 },
160 .probe = men_z188_probe,
161 .remove = men_z188_remove,
162 .id_table = men_z188_ids,
163 };
164 module_mcb_driver(men_z188_driver);
165
166 MODULE_AUTHOR("Johannes Thumshirn <johannes.thumshirn@men.de>");
167 MODULE_LICENSE("GPL");
168 MODULE_DESCRIPTION("IIO ADC driver for MEN 16z188 ADC Core");
169 MODULE_ALIAS("mcb:16z188");