1 // SPDX-License-Identifier: GPL-2.0
3  * DAC7612 Dual, 12-Bit Serial input Digital-to-Analog Converter
8  * Licensed under the GPL-2.
26 	 * Lock to protect the state of the device from potential concurrent
27 	 * write accesses from userspace. The write operation requires an
28 	 * SPI write, then toggling of a GPIO, so the lock aims to protect
44 	priv->data[0] = BIT(DAC7612_START) | (channel << DAC7612_ADDRESS);  in dac7612_cmd_single()
45 	priv->data[0] |= val >> 8;  in dac7612_cmd_single()
46 	priv->data[1] = val & 0xff;  in dac7612_cmd_single()
48 	priv->cache[channel] = val;  in dac7612_cmd_single()
50 	ret = spi_write(priv->spi, priv->data, sizeof(priv->data));  in dac7612_cmd_single()
54 	gpiod_set_value(priv->loaddacs, 1);  in dac7612_cmd_single()
55 	gpiod_set_value(priv->loaddacs, 0);  in dac7612_cmd_single()
84 		*val = priv->cache[chan->channel];  in dac7612_read_raw()
92 		return -EINVAL;  in dac7612_read_raw()
104 		return -EINVAL;  in dac7612_write_raw()
107 		return -EINVAL;  in dac7612_write_raw()
109 	if (val == priv->cache[chan->channel])  in dac7612_write_raw()
112 	mutex_lock(&priv->lock);  in dac7612_write_raw()
113 	ret = dac7612_cmd_single(priv, chan->channel, val);  in dac7612_write_raw()
114 	mutex_unlock(&priv->lock);  in dac7612_write_raw()
131 	iio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*priv));  in dac7612_probe()
133 		return -ENOMEM;  in dac7612_probe()
139 	 * every write.  in dac7612_probe()
144 	priv->loaddacs = devm_gpiod_get_optional(&spi->dev, "ti,loaddacs",  in dac7612_probe()
146 	if (IS_ERR(priv->loaddacs))  in dac7612_probe()
147 		return PTR_ERR(priv->loaddacs);  in dac7612_probe()
148 	priv->spi = spi;  in dac7612_probe()
150 	iio_dev->info = &dac7612_info;  in dac7612_probe()
151 	iio_dev->modes = INDIO_DIRECT_MODE;  in dac7612_probe()
152 	iio_dev->channels = dac7612_channels;  in dac7612_probe()
153 	iio_dev->num_channels = ARRAY_SIZE(priv->cache);  in dac7612_probe()
154 	iio_dev->name = spi_get_device_id(spi)->name;  in dac7612_probe()
156 	mutex_init(&priv->lock);  in dac7612_probe()
158 	for (i = 0; i < ARRAY_SIZE(priv->cache); i++) {  in dac7612_probe()
164 	return devm_iio_device_register(&spi->dev, iio_dev);  in dac7612_probe()
168 	{"ti-dac7612"},
183 		   .name = "ti-dac7612",