1 // SPDX-License-Identifier: GPL-2.0-only
3  * MAX1241 low-power, 12-bit serial ADC
5  * Datasheet: https://datasheets.maximintegrated.com/en/ds/MAX1240-MAX1241.pdf
19 	max1241,  enumerator
22 struct max1241 {  struct
42 static int max1241_read(struct max1241 *adc)  in max1241_read()  argument
58 			.rx_buf = &adc->data,  in max1241_read()
63 	return spi_sync_transfer(adc->spi, xfers, ARRAY_SIZE(xfers));  in max1241_read()
71 	struct max1241 *adc = iio_priv(indio_dev);  in max1241_read_raw()
75 		mutex_lock(&adc->lock);  in max1241_read_raw()
77 		if (adc->shutdown) {  in max1241_read_raw()
78 			gpiod_set_value(adc->shutdown, 0);  in max1241_read_raw()
81 			gpiod_set_value(adc->shutdown, 1);  in max1241_read_raw()
86 			mutex_unlock(&adc->lock);  in max1241_read_raw()
90 		*val = (be16_to_cpu(adc->data) >> 3) & MAX1241_VAL_MASK;  in max1241_read_raw()
92 		mutex_unlock(&adc->lock);  in max1241_read_raw()
95 		vref_uV = regulator_get_voltage(adc->vref);  in max1241_read_raw()
105 		return -EINVAL;  in max1241_read_raw()
115 	struct max1241 *adc = data;  in max1241_disable_vdd_action()
116 	struct device *dev = &adc->spi->dev;  in max1241_disable_vdd_action()
119 	err = regulator_disable(adc->vdd);  in max1241_disable_vdd_action()
126 	struct max1241 *adc = data;  in max1241_disable_vref_action()
127 	struct device *dev = &adc->spi->dev;  in max1241_disable_vref_action()
130 	err = regulator_disable(adc->vref);  in max1241_disable_vref_action()
137 	struct device *dev = &spi->dev;  in max1241_probe()
139 	struct max1241 *adc;  in max1241_probe()
144 		return -ENOMEM;  in max1241_probe()
147 	adc->spi = spi;  in max1241_probe()
148 	mutex_init(&adc->lock);  in max1241_probe()
150 	adc->vdd = devm_regulator_get(dev, "vdd");  in max1241_probe()
151 	if (IS_ERR(adc->vdd))  in max1241_probe()
152 		return dev_err_probe(dev, PTR_ERR(adc->vdd),  in max1241_probe()
155 	ret = regulator_enable(adc->vdd);  in max1241_probe()
165 	adc->vref = devm_regulator_get(dev, "vref");  in max1241_probe()
166 	if (IS_ERR(adc->vref))  in max1241_probe()
167 		return dev_err_probe(dev, PTR_ERR(adc->vref),  in max1241_probe()
170 	ret = regulator_enable(adc->vref);  in max1241_probe()
180 	adc->shutdown = devm_gpiod_get_optional(dev, "shutdown",  in max1241_probe()
182 	if (IS_ERR(adc->shutdown))  in max1241_probe()
183 		return dev_err_probe(dev, PTR_ERR(adc->shutdown),  in max1241_probe()
186 	if (adc->shutdown)  in max1241_probe()
187 		dev_dbg(dev, "shutdown pin passed, low-power mode enabled");  in max1241_probe()
189 		dev_dbg(dev, "no shutdown pin passed, low-power mode disabled");  in max1241_probe()
191 	indio_dev->name = spi_get_device_id(spi)->name;  in max1241_probe()
192 	indio_dev->info = &max1241_info;  in max1241_probe()
193 	indio_dev->modes = INDIO_DIRECT_MODE;  in max1241_probe()
194 	indio_dev->channels = max1241_channels;  in max1241_probe()
195 	indio_dev->num_channels = ARRAY_SIZE(max1241_channels);  in max1241_probe()
201 	{ "max1241", max1241 },
206 	{ .compatible = "maxim,max1241" },
213 		.name = "max1241",
222 MODULE_DESCRIPTION("MAX1241 ADC driver");