1 // SPDX-License-Identifier: GPL-2.0
13  * divided voltage is provided by a vref regulator.
15  *                   .------.
16  *    .-----------.  |      |
17  *    | vref      |--'    .---.
18  *    | regulator |--.    |   |
19  *    '-----------'  |    | d |
20  *                   |    | p |
22  *                   |    | t |<---------+
24  *                   |    '---'       dac output voltage
26  *                   '------+------------+
38 	struct regulator *vref;  member
62 		return iio_read_channel_raw(dac->dpot, val);  in dpot_dac_read_raw()
65 		ret = iio_read_channel_scale(dac->dpot, val, val2);  in dpot_dac_read_raw()
69 			do_div(tmp, dac->max_ohms);  in dpot_dac_read_raw()
70 			tmp *= regulator_get_voltage(dac->vref) / 1000;  in dpot_dac_read_raw()
84 			*val *= regulator_get_voltage(dac->vref) / 1000;  in dpot_dac_read_raw()
85 			*val2 *= dac->max_ohms;  in dpot_dac_read_raw()
92 	return -EINVAL;  in dpot_dac_read_raw()
105 		return iio_read_avail_channel_raw(dac->dpot, vals, length);  in dpot_dac_read_avail()
108 	return -EINVAL;  in dpot_dac_read_avail()
119 		return iio_write_channel_raw(dac->dpot, val);  in dpot_dac_write_raw()
122 	return -EINVAL;  in dpot_dac_write_raw()
133 	struct device *dev = &indio_dev->dev;  in dpot_dac_channel_max_ohms()
141 	ret = iio_read_max_channel_raw(dac->dpot, &max);  in dpot_dac_channel_max_ohms()
147 	switch (iio_read_channel_scale(dac->dpot, &val, &val2)) {  in dpot_dac_channel_max_ohms()
162 	return -EINVAL;  in dpot_dac_channel_max_ohms()
167 	struct device *dev = &pdev->dev;  in dpot_dac_probe()
175 		return -ENOMEM;  in dpot_dac_probe()
180 	indio_dev->name = dev_name(dev);  in dpot_dac_probe()
181 	indio_dev->info = &dpot_dac_info;  in dpot_dac_probe()
182 	indio_dev->modes = INDIO_DIRECT_MODE;  in dpot_dac_probe()
183 	indio_dev->channels = &dpot_dac_iio_channel;  in dpot_dac_probe()
184 	indio_dev->num_channels = 1;  in dpot_dac_probe()
186 	dac->vref = devm_regulator_get(dev, "vref");  in dpot_dac_probe()
187 	if (IS_ERR(dac->vref))  in dpot_dac_probe()
188 		return dev_err_probe(&pdev->dev, PTR_ERR(dac->vref),  in dpot_dac_probe()
189 				     "failed to get vref regulator\n");  in dpot_dac_probe()
191 	dac->dpot = devm_iio_channel_get(dev, "dpot");  in dpot_dac_probe()
192 	if (IS_ERR(dac->dpot))  in dpot_dac_probe()
193 		return dev_err_probe(&pdev->dev, PTR_ERR(dac->dpot),  in dpot_dac_probe()
196 	ret = iio_get_channel_type(dac->dpot, &type);  in dpot_dac_probe()
202 		return -EINVAL;  in dpot_dac_probe()
208 	dac->max_ohms = ret;  in dpot_dac_probe()
210 	ret = regulator_enable(dac->vref);  in dpot_dac_probe()
212 		dev_err(dev, "failed to enable the vref regulator\n");  in dpot_dac_probe()
225 	regulator_disable(dac->vref);  in dpot_dac_probe()
235 	regulator_disable(dac->vref);  in dpot_dac_remove()
241 	{ .compatible = "dpot-dac" },
250 		.name = "iio-dpot-dac",