diff mbox series

iio:dac:ti-dac7612: Add driver for Texas Instruments DAC7612

Message ID 20190124213248.11900-1-ricardo@ribalda.com (mailing list archive)
State New, archived
Headers show
Series iio:dac:ti-dac7612: Add driver for Texas Instruments DAC7612 | expand

Commit Message

Ricardo Ribalda Delgado Jan. 24, 2019, 9:32 p.m. UTC
It is a driver for Texas Instruments Dual, 12-Bit Serial Input
Digital-to-Analog Converter.

Datasheet of this chip:
http://www.ti.com/lit/ds/sbas106/sbas106.pdf

Signed-off-by: Ricardo Ribalda Delgado <ricardo@ribalda.com>
---
 MAINTAINERS                  |   6 ++
 drivers/iio/dac/Kconfig      |  10 +++
 drivers/iio/dac/Makefile     |   1 +
 drivers/iio/dac/ti-dac7612.c | 170 +++++++++++++++++++++++++++++++++++
 4 files changed, 187 insertions(+)
 create mode 100644 drivers/iio/dac/ti-dac7612.c
diff mbox series

Patch

diff --git a/MAINTAINERS b/MAINTAINERS
index d039f66a5cef..30ba5435906b 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -14877,6 +14877,12 @@  F:	Documentation/devicetree/bindings/clock/ti,sci-clk.txt
 F:	drivers/clk/keystone/sci-clk.c
 F:	drivers/reset/reset-ti-sci.c
 
+Texas Instruments' DAC7612 DAC Driver
+M:	Ricardo Ribalda <ricardo@ribalda.com>
+L:	linux-iio@vger.kernel.org
+S:	Supported
+F:	drivers/iio/dac/ti-dac7612.c
+
 THANKO'S RAREMONO AM/FM/SW RADIO RECEIVER USB DRIVER
 M:	Hans Verkuil <hverkuil@xs4all.nl>
 L:	linux-media@vger.kernel.org
diff --git a/drivers/iio/dac/Kconfig b/drivers/iio/dac/Kconfig
index f28daf67db6a..fbef9107acad 100644
--- a/drivers/iio/dac/Kconfig
+++ b/drivers/iio/dac/Kconfig
@@ -375,6 +375,16 @@  config TI_DAC7311
 
 	  If compiled as a module, it will be called ti-dac7311.
 
+config TI_DAC7612
+	tristate "Texas Instruments 12-bit 2-channel DAC driver"
+	depends on SPI_MASTER && GPIOLIB
+	help
+	  Driver for the Texas Instruments DAC7612, DAC7612U, DAC7612UB
+	  The driver hand drive the load pin automatically, otherwise
+	  it needs to be toggled manually.
+
+	  If compiled as a module, it will be called ti-dac7612.
+
 config VF610_DAC
 	tristate "Vybrid vf610 DAC driver"
 	depends on OF
diff --git a/drivers/iio/dac/Makefile b/drivers/iio/dac/Makefile
index f0a37c93de8e..1369fa1d2f0e 100644
--- a/drivers/iio/dac/Makefile
+++ b/drivers/iio/dac/Makefile
@@ -41,4 +41,5 @@  obj-$(CONFIG_STM32_DAC) += stm32-dac.o
 obj-$(CONFIG_TI_DAC082S085) += ti-dac082s085.o
 obj-$(CONFIG_TI_DAC5571) += ti-dac5571.o
 obj-$(CONFIG_TI_DAC7311) += ti-dac7311.o
+obj-$(CONFIG_TI_DAC7612) += ti-dac7612.o
 obj-$(CONFIG_VF610_DAC) += vf610_dac.o
diff --git a/drivers/iio/dac/ti-dac7612.c b/drivers/iio/dac/ti-dac7612.c
new file mode 100644
index 000000000000..5b374aa287c7
--- /dev/null
+++ b/drivers/iio/dac/ti-dac7612.c
@@ -0,0 +1,170 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * DAC7612 Dual, 12-Bit Serial input Digital-to-Analog Converter
+ *
+ * Copyright 2019 Qtechnology A/S
+ * 2019 Ricardo Ribalda <ricardo@ribalda.com>
+ *
+ * Licensed under the GPL-2.
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/spi/spi.h>
+#include <linux/gpio/consumer.h>
+#include <linux/iio/iio.h>
+
+#define NUM_CHANS 2
+#define RESOLUTION 12
+
+struct dac7612 {
+	struct spi_device *spi;
+	struct gpio_desc *nld;
+	uint16_t cache[NUM_CHANS];
+};
+
+static int dac7612_cmd_single(struct dac7612 *priv, int channel, u16 val)
+{
+	uint8_t buffer[2];
+	int ret;
+
+	if (channel >= NUM_CHANS)
+		return -EINVAL;
+
+	buffer[0] = BIT(5) | (channel << 4) | (val >> 8);
+	buffer[1] = val & 0xff;
+
+	priv->cache[channel] = val;
+
+	ret = spi_write(priv->spi, buffer, sizeof(buffer));
+	if (ret)
+		return ret;
+
+	gpiod_set_value(priv->nld, 0);
+	gpiod_set_value(priv->nld, 1);
+
+	return 0;
+}
+
+#define dac7612_CHANNEL(chan, name) {				\
+	.type = IIO_VOLTAGE,					\
+	.channel = (chan),					\
+	.address = (chan),					\
+	.indexed = true,					\
+	.output = true,						\
+	.datasheet_name = name,					\
+	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),		\
+	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),	\
+	.scan_type = {						\
+			.sign = 'u',				\
+			.realbits = RESOLUTION,			\
+			.storagebits = RESOLUTION,		\
+	},							\
+}
+
+static const struct iio_chan_spec dac7612_channels[] = {
+	dac7612_CHANNEL(0, "OUTA"),
+	dac7612_CHANNEL(1, "OUTB"),
+};
+
+static int dac7612_read_raw(struct iio_dev *iio_dev,
+			    const struct iio_chan_spec *chan,
+			    int *val, int *val2, long mask)
+{
+	struct dac7612 *priv;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		priv = iio_priv(iio_dev);
+		*val = priv->cache[chan->channel];
+		return IIO_VAL_INT;
+
+	case IIO_CHAN_INFO_SCALE:
+		*val = 1;
+		*val2 = 1000;
+		return IIO_VAL_FRACTIONAL;
+
+	default:
+		return -EINVAL;
+	}
+}
+
+static int dac7612_write_raw(struct iio_dev *iio_dev,
+			     const struct iio_chan_spec *chan,
+			     int val, int val2, long mask)
+{
+	struct dac7612 *priv;
+	int ret;
+
+	if (mask != IIO_CHAN_INFO_RAW)
+		return -EINVAL;
+
+	if ((val >= BIT(RESOLUTION)) || val < 0)
+		return -EINVAL;
+
+	priv = iio_priv(iio_dev);
+	if (val == priv->cache[chan->channel])
+		return 0;
+
+	mutex_lock(&iio_dev->mlock);
+	ret = dac7612_cmd_single(priv, chan->channel, val);
+	mutex_unlock(&iio_dev->mlock);
+
+	return ret;
+}
+
+static const struct iio_info dac7612_info = {
+	.read_raw = dac7612_read_raw,
+	.write_raw = dac7612_write_raw,
+};
+
+static int dac7612_probe(struct spi_device *spi)
+{
+	struct iio_dev *iio_dev;
+	struct dac7612 *priv;
+	int i;
+	int ret;
+
+	iio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*priv));
+	if (!iio_dev)
+		return -ENOMEM;
+
+	priv = iio_priv(iio_dev);
+	priv->nld = devm_gpiod_get_optional(&spi->dev, "nLD", GPIOD_OUT_HIGH);
+	if (IS_ERR(priv->nld))
+		return PTR_ERR(priv->nld);
+	priv->spi = spi;
+	spi_set_drvdata(spi, iio_dev);
+	iio_dev->dev.parent = &spi->dev;
+	iio_dev->info = &dac7612_info;
+	iio_dev->modes = INDIO_DIRECT_MODE;
+	iio_dev->channels = dac7612_channels;
+	iio_dev->num_channels = NUM_CHANS;
+	iio_dev->name = spi_get_device_id(spi)->name;
+
+	for (i = 0; i < NUM_CHANS; i++) {
+		ret = dac7612_cmd_single(priv, i, 0);
+		if (ret)
+			return ret;
+	}
+
+	return devm_iio_device_register(&spi->dev, iio_dev);
+}
+
+static const struct spi_device_id dac7612_id[] = {
+	{"ti-dac7612"},
+	{}
+};
+MODULE_DEVICE_TABLE(spi, dac7612_id);
+
+static struct spi_driver dac7612_driver = {
+	.driver = {
+		   .name = "ti-dac7612",
+		   },
+	.probe = dac7612_probe,
+	.id_table = dac7612_id,
+};
+module_spi_driver(dac7612_driver);
+
+MODULE_AUTHOR("Ricardo Ribalda <ricardo@ribalda.com>");
+MODULE_DESCRIPTION("Texas Instruments DAC7612 DAC driver");
+MODULE_LICENSE("GPL v2");