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path: root/drivers/iio/dac/ad5592r.c
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Diffstat (limited to 'drivers/iio/dac/ad5592r.c')
-rw-r--r--drivers/iio/dac/ad5592r.c164
1 files changed, 164 insertions, 0 deletions
diff --git a/drivers/iio/dac/ad5592r.c b/drivers/iio/dac/ad5592r.c
new file mode 100644
index 000000000..0b235a2c7
--- /dev/null
+++ b/drivers/iio/dac/ad5592r.c
@@ -0,0 +1,164 @@
+/*
+ * AD5592R Digital <-> Analog converters driver
+ *
+ * Copyright 2015-2016 Analog Devices Inc.
+ * Author: Paul Cercueil <paul.cercueil@analog.com>
+ *
+ * Licensed under the GPL-2.
+ */
+
+#include "ad5592r-base.h"
+
+#include <linux/bitops.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/spi/spi.h>
+
+#define AD5592R_GPIO_READBACK_EN BIT(10)
+#define AD5592R_LDAC_READBACK_EN BIT(6)
+
+static int ad5592r_spi_wnop_r16(struct ad5592r_state *st, u16 *buf)
+{
+ struct spi_device *spi = container_of(st->dev, struct spi_device, dev);
+ struct spi_transfer t = {
+ .tx_buf = &st->spi_msg_nop,
+ .rx_buf = buf,
+ .len = 2
+ };
+
+ st->spi_msg_nop = 0; /* NOP */
+
+ return spi_sync_transfer(spi, &t, 1);
+}
+
+static int ad5592r_write_dac(struct ad5592r_state *st, unsigned chan, u16 value)
+{
+ struct spi_device *spi = container_of(st->dev, struct spi_device, dev);
+
+ st->spi_msg = cpu_to_be16(BIT(15) | (chan << 12) | value);
+
+ return spi_write(spi, &st->spi_msg, sizeof(st->spi_msg));
+}
+
+static int ad5592r_read_adc(struct ad5592r_state *st, unsigned chan, u16 *value)
+{
+ struct spi_device *spi = container_of(st->dev, struct spi_device, dev);
+ int ret;
+
+ st->spi_msg = cpu_to_be16((AD5592R_REG_ADC_SEQ << 11) | BIT(chan));
+
+ ret = spi_write(spi, &st->spi_msg, sizeof(st->spi_msg));
+ if (ret)
+ return ret;
+
+ /*
+ * Invalid data:
+ * See Figure 40. Single-Channel ADC Conversion Sequence
+ */
+ ret = ad5592r_spi_wnop_r16(st, &st->spi_msg);
+ if (ret)
+ return ret;
+
+ ret = ad5592r_spi_wnop_r16(st, &st->spi_msg);
+ if (ret)
+ return ret;
+
+ *value = be16_to_cpu(st->spi_msg);
+
+ return 0;
+}
+
+static int ad5592r_reg_write(struct ad5592r_state *st, u8 reg, u16 value)
+{
+ struct spi_device *spi = container_of(st->dev, struct spi_device, dev);
+
+ st->spi_msg = cpu_to_be16((reg << 11) | value);
+
+ return spi_write(spi, &st->spi_msg, sizeof(st->spi_msg));
+}
+
+static int ad5592r_reg_read(struct ad5592r_state *st, u8 reg, u16 *value)
+{
+ struct spi_device *spi = container_of(st->dev, struct spi_device, dev);
+ int ret;
+
+ st->spi_msg = cpu_to_be16((AD5592R_REG_LDAC << 11) |
+ AD5592R_LDAC_READBACK_EN | (reg << 2));
+
+ ret = spi_write(spi, &st->spi_msg, sizeof(st->spi_msg));
+ if (ret)
+ return ret;
+
+ ret = ad5592r_spi_wnop_r16(st, &st->spi_msg);
+ if (ret)
+ return ret;
+
+ *value = be16_to_cpu(st->spi_msg);
+
+ return 0;
+}
+
+static int ad5593r_gpio_read(struct ad5592r_state *st, u8 *value)
+{
+ int ret;
+
+ ret = ad5592r_reg_write(st, AD5592R_REG_GPIO_IN_EN,
+ AD5592R_GPIO_READBACK_EN | st->gpio_in);
+ if (ret)
+ return ret;
+
+ ret = ad5592r_spi_wnop_r16(st, &st->spi_msg);
+ if (ret)
+ return ret;
+
+ *value = (u8) be16_to_cpu(st->spi_msg);
+
+ return 0;
+}
+
+static const struct ad5592r_rw_ops ad5592r_rw_ops = {
+ .write_dac = ad5592r_write_dac,
+ .read_adc = ad5592r_read_adc,
+ .reg_write = ad5592r_reg_write,
+ .reg_read = ad5592r_reg_read,
+ .gpio_read = ad5593r_gpio_read,
+};
+
+static int ad5592r_spi_probe(struct spi_device *spi)
+{
+ const struct spi_device_id *id = spi_get_device_id(spi);
+
+ return ad5592r_probe(&spi->dev, id->name, &ad5592r_rw_ops);
+}
+
+static int ad5592r_spi_remove(struct spi_device *spi)
+{
+ return ad5592r_remove(&spi->dev);
+}
+
+static const struct spi_device_id ad5592r_spi_ids[] = {
+ { .name = "ad5592r", },
+ {}
+};
+MODULE_DEVICE_TABLE(spi, ad5592r_spi_ids);
+
+static const struct of_device_id ad5592r_of_match[] = {
+ { .compatible = "adi,ad5592r", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, ad5592r_of_match);
+
+static struct spi_driver ad5592r_spi_driver = {
+ .driver = {
+ .name = "ad5592r",
+ .of_match_table = of_match_ptr(ad5592r_of_match),
+ },
+ .probe = ad5592r_spi_probe,
+ .remove = ad5592r_spi_remove,
+ .id_table = ad5592r_spi_ids,
+};
+module_spi_driver(ad5592r_spi_driver);
+
+MODULE_AUTHOR("Paul Cercueil <paul.cercueil@analog.com>");
+MODULE_DESCRIPTION("Analog Devices AD5592R multi-channel converters");
+MODULE_LICENSE("GPL v2");