1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
|
// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2015 Samsung Electronics
* Przemyslaw Marczak <p.marczak@samsung.com>
*/
#include <common.h>
#include <errno.h>
#include <dm.h>
#include <adc.h>
#include <sandbox-adc.h>
/**
* struct sandbox_adc_priv - sandbox ADC device's operation status and data
*
* @conversion_status - conversion status: ACTIVE (started) / INACTIVE (stopped)
* @conversion_mode - conversion mode: single or multi-channel
* @active_channel - active channel number, valid for single channel mode
* data[] - channels data
*/
struct sandbox_adc_priv {
int conversion_status;
int conversion_mode;
int active_channel_mask;
unsigned int data[4];
};
int sandbox_adc_start_channel(struct udevice *dev, int channel)
{
struct sandbox_adc_priv *priv = dev_get_priv(dev);
/* Set single-channel mode */
priv->conversion_mode = SANDBOX_ADC_MODE_SINGLE_CHANNEL;
/* Select channel */
priv->active_channel_mask = 1 << channel;
/* Start conversion */
priv->conversion_status = SANDBOX_ADC_ACTIVE;
return 0;
}
int sandbox_adc_start_channels(struct udevice *dev, unsigned int channel_mask)
{
struct sandbox_adc_priv *priv = dev_get_priv(dev);
/* Set single-channel mode */
priv->conversion_mode = SANDBOX_ADC_MODE_MULTI_CHANNEL;
/* Select channel */
priv->active_channel_mask = channel_mask;
/* Start conversion */
priv->conversion_status = SANDBOX_ADC_ACTIVE;
return 0;
}
int sandbox_adc_channel_data(struct udevice *dev, int channel,
unsigned int *data)
{
struct sandbox_adc_priv *priv = dev_get_priv(dev);
/* For single-channel conversion mode, check if channel was selected */
if ((priv->conversion_mode == SANDBOX_ADC_MODE_SINGLE_CHANNEL) &&
!(priv->active_channel_mask & (1 << channel))) {
pr_err("Request for an inactive channel!");
return -EINVAL;
}
/* The conversion must be started before reading the data */
if (priv->conversion_status == SANDBOX_ADC_INACTIVE)
return -EIO;
*data = priv->data[channel];
return 0;
}
int sandbox_adc_channels_data(struct udevice *dev, unsigned int channel_mask,
struct adc_channel *channels)
{
struct sandbox_adc_priv *priv = dev_get_priv(dev);
int i;
/* Return error for single-channel conversion mode */
if (priv->conversion_mode == SANDBOX_ADC_MODE_SINGLE_CHANNEL) {
pr_err("ADC in single-channel mode!");
return -EPERM;
}
/* Check channel selection */
if (!(priv->active_channel_mask & channel_mask)) {
pr_err("Request for an inactive channel!");
return -EINVAL;
}
/* The conversion must be started before reading the data */
if (priv->conversion_status == SANDBOX_ADC_INACTIVE)
return -EIO;
for (i = 0; i < SANDBOX_ADC_CHANNELS; i++) {
if (!((channel_mask >> i) & 0x1))
continue;
channels->data = priv->data[i];
channels->id = i;
channels++;
}
return 0;
}
int sandbox_adc_stop(struct udevice *dev)
{
struct sandbox_adc_priv *priv = dev_get_priv(dev);
/* Start conversion */
priv->conversion_status = SANDBOX_ADC_INACTIVE;
return 0;
}
int sandbox_adc_probe(struct udevice *dev)
{
struct sandbox_adc_priv *priv = dev_get_priv(dev);
/* Stop conversion */
priv->conversion_status = SANDBOX_ADC_INACTIVE;
/* Set single-channel mode */
priv->conversion_mode = SANDBOX_ADC_MODE_SINGLE_CHANNEL;
/* Deselect all channels */
priv->active_channel_mask = 0;
/* Set sandbox test data */
priv->data[0] = SANDBOX_ADC_CHANNEL0_DATA;
priv->data[1] = SANDBOX_ADC_CHANNEL1_DATA;
priv->data[2] = SANDBOX_ADC_CHANNEL2_DATA;
priv->data[3] = SANDBOX_ADC_CHANNEL3_DATA;
return 0;
}
int sandbox_adc_of_to_plat(struct udevice *dev)
{
struct adc_uclass_plat *uc_pdata = dev_get_uclass_plat(dev);
uc_pdata->data_mask = SANDBOX_ADC_DATA_MASK;
uc_pdata->data_format = ADC_DATA_FORMAT_BIN;
uc_pdata->data_timeout_us = 0;
/* Mask available channel bits: [0:3] */
uc_pdata->channel_mask = (1 << SANDBOX_ADC_CHANNELS) - 1;
return 0;
}
static const struct adc_ops sandbox_adc_ops = {
.start_channel = sandbox_adc_start_channel,
.start_channels = sandbox_adc_start_channels,
.channel_data = sandbox_adc_channel_data,
.channels_data = sandbox_adc_channels_data,
.stop = sandbox_adc_stop,
};
static const struct udevice_id sandbox_adc_ids[] = {
{ .compatible = "sandbox,adc" },
{ }
};
U_BOOT_DRIVER(sandbox_adc) = {
.name = "sandbox-adc",
.id = UCLASS_ADC,
.of_match = sandbox_adc_ids,
.ops = &sandbox_adc_ops,
.probe = sandbox_adc_probe,
.of_to_plat = sandbox_adc_of_to_plat,
.priv_auto = sizeof(struct sandbox_adc_priv),
};
|