5  * Copyright (c) 2018-2018 David Veenstra <davidjulianveenstra@gmail.com>
6  * Copyright (c) 2010-2010 Analog Devices Inc.
16 #include <linux/gpio.h>
17 #include <linux/gpio/consumer.h>
20 #include <linux/spi/spi.h>
35  * struct ad2s1200_state - driver instance specific data.
36  * @lock:	protects both the GPIO pins and the rx buffer.
37  * @sdev:	spi device.
38  * @sample:	GPIO pin SAMPLE.
39  * @rdvel:	GPIO pin RDVEL.
40  * @rx:		buffer for spi transfers.
61 		switch (chan->type) {  in ad2s1200_read_raw()
63 			/* 2 * Pi / (2^12 - 1) ~= 0.001534355 */  in ad2s1200_read_raw()
73 			return -EINVAL;  in ad2s1200_read_raw()
77 		mutex_lock(&st->lock);  in ad2s1200_read_raw()
78 		gpiod_set_value(st->sample, 0);  in ad2s1200_read_raw()
82 		gpiod_set_value(st->sample, 1);  in ad2s1200_read_raw()
83 		gpiod_set_value(st->rdvel, !!(chan->type == IIO_ANGL));  in ad2s1200_read_raw()
85 		ret = spi_read(st->sdev, &st->rx, 2);  in ad2s1200_read_raw()
87 			mutex_unlock(&st->lock);  in ad2s1200_read_raw()
91 		switch (chan->type) {  in ad2s1200_read_raw()
93 			*val = be16_to_cpup(&st->rx) >> 4;  in ad2s1200_read_raw()
96 			*val = sign_extend32(be16_to_cpup(&st->rx) >> 4, 11);  in ad2s1200_read_raw()
99 			mutex_unlock(&st->lock);  in ad2s1200_read_raw()
100 			return -EINVAL;  in ad2s1200_read_raw()
105 		mutex_unlock(&st->lock);  in ad2s1200_read_raw()
112 	return -EINVAL;  in ad2s1200_read_raw()
135 static int ad2s1200_probe(struct spi_device *spi)  in ad2s1200_probe()  argument
141 	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));  in ad2s1200_probe()
143 		return -ENOMEM;  in ad2s1200_probe()
145 	spi_set_drvdata(spi, indio_dev);  in ad2s1200_probe()
147 	mutex_init(&st->lock);  in ad2s1200_probe()
148 	st->sdev = spi;  in ad2s1200_probe()
150 	st->sample = devm_gpiod_get(&spi->dev, "adi,sample", GPIOD_OUT_LOW);  in ad2s1200_probe()
151 	if (IS_ERR(st->sample)) {  in ad2s1200_probe()
152 		dev_err(&spi->dev, "Failed to claim SAMPLE gpio: err=%ld\n",  in ad2s1200_probe()
153 			PTR_ERR(st->sample));  in ad2s1200_probe()
154 		return PTR_ERR(st->sample);  in ad2s1200_probe()
157 	st->rdvel = devm_gpiod_get(&spi->dev, "adi,rdvel", GPIOD_OUT_LOW);  in ad2s1200_probe()
158 	if (IS_ERR(st->rdvel)) {  in ad2s1200_probe()
159 		dev_err(&spi->dev, "Failed to claim RDVEL gpio: err=%ld\n",  in ad2s1200_probe()
160 			PTR_ERR(st->rdvel));  in ad2s1200_probe()
161 		return PTR_ERR(st->rdvel);  in ad2s1200_probe()
164 	indio_dev->dev.parent = &spi->dev;  in ad2s1200_probe()
165 	indio_dev->info = &ad2s1200_info;  in ad2s1200_probe()
166 	indio_dev->modes = INDIO_DIRECT_MODE;  in ad2s1200_probe()
167 	indio_dev->channels = ad2s1200_channels;  in ad2s1200_probe()
168 	indio_dev->num_channels = ARRAY_SIZE(ad2s1200_channels);  in ad2s1200_probe()
169 	indio_dev->name = spi_get_device_id(spi)->name;  in ad2s1200_probe()
171 	spi->max_speed_hz = AD2S1200_HZ;  in ad2s1200_probe()
172 	spi->mode = SPI_MODE_3;  in ad2s1200_probe()
173 	ret = spi_setup(spi);  in ad2s1200_probe()
176 		dev_err(&spi->dev, "spi_setup failed!\n");  in ad2s1200_probe()
180 	return devm_iio_device_register(&spi->dev, indio_dev);  in ad2s1200_probe()
195 MODULE_DEVICE_TABLE(spi, ad2s1200_id);
209 MODULE_DESCRIPTION("Analog Devices AD2S1200/1205 Resolver to Digital SPI driver");