1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-or-later
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * Nano River Technologies viperboard IIO ADC driver
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * (C) 2012 by Lemonage GmbH
6*4882a593Smuzhiyun * Author: Lars Poeschel <poeschel@lemonage.de>
7*4882a593Smuzhiyun * All rights reserved.
8*4882a593Smuzhiyun */
9*4882a593Smuzhiyun
10*4882a593Smuzhiyun #include <linux/kernel.h>
11*4882a593Smuzhiyun #include <linux/errno.h>
12*4882a593Smuzhiyun #include <linux/module.h>
13*4882a593Smuzhiyun #include <linux/slab.h>
14*4882a593Smuzhiyun #include <linux/types.h>
15*4882a593Smuzhiyun #include <linux/mutex.h>
16*4882a593Smuzhiyun #include <linux/platform_device.h>
17*4882a593Smuzhiyun
18*4882a593Smuzhiyun #include <linux/usb.h>
19*4882a593Smuzhiyun #include <linux/iio/iio.h>
20*4882a593Smuzhiyun
21*4882a593Smuzhiyun #include <linux/mfd/viperboard.h>
22*4882a593Smuzhiyun
23*4882a593Smuzhiyun #define VPRBRD_ADC_CMD_GET 0x00
24*4882a593Smuzhiyun
25*4882a593Smuzhiyun struct vprbrd_adc_msg {
26*4882a593Smuzhiyun u8 cmd;
27*4882a593Smuzhiyun u8 chan;
28*4882a593Smuzhiyun u8 val;
29*4882a593Smuzhiyun } __packed;
30*4882a593Smuzhiyun
31*4882a593Smuzhiyun struct vprbrd_adc {
32*4882a593Smuzhiyun struct vprbrd *vb;
33*4882a593Smuzhiyun };
34*4882a593Smuzhiyun
35*4882a593Smuzhiyun #define VPRBRD_ADC_CHANNEL(_index) { \
36*4882a593Smuzhiyun .type = IIO_VOLTAGE, \
37*4882a593Smuzhiyun .indexed = 1, \
38*4882a593Smuzhiyun .channel = _index, \
39*4882a593Smuzhiyun .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
40*4882a593Smuzhiyun }
41*4882a593Smuzhiyun
42*4882a593Smuzhiyun static struct iio_chan_spec const vprbrd_adc_iio_channels[] = {
43*4882a593Smuzhiyun VPRBRD_ADC_CHANNEL(0),
44*4882a593Smuzhiyun VPRBRD_ADC_CHANNEL(1),
45*4882a593Smuzhiyun VPRBRD_ADC_CHANNEL(2),
46*4882a593Smuzhiyun VPRBRD_ADC_CHANNEL(3),
47*4882a593Smuzhiyun };
48*4882a593Smuzhiyun
vprbrd_iio_read_raw(struct iio_dev * iio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long info)49*4882a593Smuzhiyun static int vprbrd_iio_read_raw(struct iio_dev *iio_dev,
50*4882a593Smuzhiyun struct iio_chan_spec const *chan,
51*4882a593Smuzhiyun int *val,
52*4882a593Smuzhiyun int *val2,
53*4882a593Smuzhiyun long info)
54*4882a593Smuzhiyun {
55*4882a593Smuzhiyun int ret, error = 0;
56*4882a593Smuzhiyun struct vprbrd_adc *adc = iio_priv(iio_dev);
57*4882a593Smuzhiyun struct vprbrd *vb = adc->vb;
58*4882a593Smuzhiyun struct vprbrd_adc_msg *admsg = (struct vprbrd_adc_msg *)vb->buf;
59*4882a593Smuzhiyun
60*4882a593Smuzhiyun switch (info) {
61*4882a593Smuzhiyun case IIO_CHAN_INFO_RAW:
62*4882a593Smuzhiyun mutex_lock(&vb->lock);
63*4882a593Smuzhiyun
64*4882a593Smuzhiyun admsg->cmd = VPRBRD_ADC_CMD_GET;
65*4882a593Smuzhiyun admsg->chan = chan->channel;
66*4882a593Smuzhiyun admsg->val = 0x00;
67*4882a593Smuzhiyun
68*4882a593Smuzhiyun ret = usb_control_msg(vb->usb_dev,
69*4882a593Smuzhiyun usb_sndctrlpipe(vb->usb_dev, 0), VPRBRD_USB_REQUEST_ADC,
70*4882a593Smuzhiyun VPRBRD_USB_TYPE_OUT, 0x0000, 0x0000, admsg,
71*4882a593Smuzhiyun sizeof(struct vprbrd_adc_msg), VPRBRD_USB_TIMEOUT_MS);
72*4882a593Smuzhiyun if (ret != sizeof(struct vprbrd_adc_msg)) {
73*4882a593Smuzhiyun dev_err(&iio_dev->dev, "usb send error on adc read\n");
74*4882a593Smuzhiyun error = -EREMOTEIO;
75*4882a593Smuzhiyun }
76*4882a593Smuzhiyun
77*4882a593Smuzhiyun ret = usb_control_msg(vb->usb_dev,
78*4882a593Smuzhiyun usb_rcvctrlpipe(vb->usb_dev, 0), VPRBRD_USB_REQUEST_ADC,
79*4882a593Smuzhiyun VPRBRD_USB_TYPE_IN, 0x0000, 0x0000, admsg,
80*4882a593Smuzhiyun sizeof(struct vprbrd_adc_msg), VPRBRD_USB_TIMEOUT_MS);
81*4882a593Smuzhiyun
82*4882a593Smuzhiyun *val = admsg->val;
83*4882a593Smuzhiyun
84*4882a593Smuzhiyun mutex_unlock(&vb->lock);
85*4882a593Smuzhiyun
86*4882a593Smuzhiyun if (ret != sizeof(struct vprbrd_adc_msg)) {
87*4882a593Smuzhiyun dev_err(&iio_dev->dev, "usb recv error on adc read\n");
88*4882a593Smuzhiyun error = -EREMOTEIO;
89*4882a593Smuzhiyun }
90*4882a593Smuzhiyun
91*4882a593Smuzhiyun if (error)
92*4882a593Smuzhiyun goto error;
93*4882a593Smuzhiyun
94*4882a593Smuzhiyun return IIO_VAL_INT;
95*4882a593Smuzhiyun default:
96*4882a593Smuzhiyun error = -EINVAL;
97*4882a593Smuzhiyun break;
98*4882a593Smuzhiyun }
99*4882a593Smuzhiyun error:
100*4882a593Smuzhiyun return error;
101*4882a593Smuzhiyun }
102*4882a593Smuzhiyun
103*4882a593Smuzhiyun static const struct iio_info vprbrd_adc_iio_info = {
104*4882a593Smuzhiyun .read_raw = &vprbrd_iio_read_raw,
105*4882a593Smuzhiyun };
106*4882a593Smuzhiyun
vprbrd_adc_probe(struct platform_device * pdev)107*4882a593Smuzhiyun static int vprbrd_adc_probe(struct platform_device *pdev)
108*4882a593Smuzhiyun {
109*4882a593Smuzhiyun struct vprbrd *vb = dev_get_drvdata(pdev->dev.parent);
110*4882a593Smuzhiyun struct vprbrd_adc *adc;
111*4882a593Smuzhiyun struct iio_dev *indio_dev;
112*4882a593Smuzhiyun int ret;
113*4882a593Smuzhiyun
114*4882a593Smuzhiyun /* registering iio */
115*4882a593Smuzhiyun indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*adc));
116*4882a593Smuzhiyun if (!indio_dev) {
117*4882a593Smuzhiyun dev_err(&pdev->dev, "failed allocating iio device\n");
118*4882a593Smuzhiyun return -ENOMEM;
119*4882a593Smuzhiyun }
120*4882a593Smuzhiyun
121*4882a593Smuzhiyun adc = iio_priv(indio_dev);
122*4882a593Smuzhiyun adc->vb = vb;
123*4882a593Smuzhiyun indio_dev->name = "viperboard adc";
124*4882a593Smuzhiyun indio_dev->info = &vprbrd_adc_iio_info;
125*4882a593Smuzhiyun indio_dev->modes = INDIO_DIRECT_MODE;
126*4882a593Smuzhiyun indio_dev->channels = vprbrd_adc_iio_channels;
127*4882a593Smuzhiyun indio_dev->num_channels = ARRAY_SIZE(vprbrd_adc_iio_channels);
128*4882a593Smuzhiyun
129*4882a593Smuzhiyun ret = devm_iio_device_register(&pdev->dev, indio_dev);
130*4882a593Smuzhiyun if (ret) {
131*4882a593Smuzhiyun dev_err(&pdev->dev, "could not register iio (adc)");
132*4882a593Smuzhiyun return ret;
133*4882a593Smuzhiyun }
134*4882a593Smuzhiyun
135*4882a593Smuzhiyun return 0;
136*4882a593Smuzhiyun }
137*4882a593Smuzhiyun
138*4882a593Smuzhiyun static struct platform_driver vprbrd_adc_driver = {
139*4882a593Smuzhiyun .driver = {
140*4882a593Smuzhiyun .name = "viperboard-adc",
141*4882a593Smuzhiyun },
142*4882a593Smuzhiyun .probe = vprbrd_adc_probe,
143*4882a593Smuzhiyun };
144*4882a593Smuzhiyun
145*4882a593Smuzhiyun module_platform_driver(vprbrd_adc_driver);
146*4882a593Smuzhiyun
147*4882a593Smuzhiyun MODULE_AUTHOR("Lars Poeschel <poeschel@lemonage.de>");
148*4882a593Smuzhiyun MODULE_DESCRIPTION("IIO ADC driver for Nano River Techs Viperboard");
149*4882a593Smuzhiyun MODULE_LICENSE("GPL");
150*4882a593Smuzhiyun MODULE_ALIAS("platform:viperboard-adc");
151