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authorLinus Torvalds <torvalds@linux-foundation.org>2012-12-11 13:59:44 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2012-12-11 13:59:44 -0800
commit8966961b31c251b854169e9886394c2a20f2cea7 (patch)
tree248a625b23335acbd5ca4b55eb136fe0dc8ba0aa /drivers/iio/dac/ad5449.c
parentMerge tag 'char-misc-3.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc (diff)
parentMerge tag 'iio-for-3.8f' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next (diff)
downloadlinux-dev-8966961b31c251b854169e9886394c2a20f2cea7.tar.xz
linux-dev-8966961b31c251b854169e9886394c2a20f2cea7.zip
Merge tag 'staging-3.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
Pull staging driver tree merge from Greg Kroah-Hartman: "Here's the big staging tree merge for 3.8-rc1 There's a lot of patches in here, the majority being the comedi rework/cleanup that has been ongoing and is causing a huge reduction in overall code size, which is amazing to watch. We also removed some older drivers (telephony and rts_pstor), and added a new one (fwserial which also came in through the tty tree due to tty api changes, take that one if you get merge conflicts.) The iio and ipack drivers are moving out of the staging area into their own part of the kernel as they have been cleaned up sufficiently and are working well. Overall, again a reduction of code: 768 files changed, 31887 insertions(+), 82166 deletions(-) All of this has been in the linux-next tree for a while. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>" * tag 'staging-3.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (1298 commits) iio: imu: adis16480: remove duplicated include from adis16480.c iio: gyro: adis16136: remove duplicated include from adis16136.c iio:imu: adis16480: show_firmware() buffer too small iio:gyro: adis16136: divide by zero in write_frequency() iio: adc: Add Texas Instruments ADC081C021/027 support iio:ad7793: Add support for the ad7796 and ad7797 iio:ad7793: Add support for the ad7798 and ad7799 staging:iio: Move ad7793 driver out of staging staging:iio:ad7793: Implement stricter id checking staging:iio:ad7793: Move register definitions from header to source staging:iio:ad7793: Rework regulator handling staging:iio:ad7793: Rework platform data staging:iio:ad7793: Use kstrtol instead of strict_strtol staging:iio:ad7793: Use usleep_range instead of msleep staging:iio:ad7793: Fix temperature scale staging:iio:ad7793: Fix VDD monitor scale staging: gdm72xx: unlock on error in init_usb() staging: panel: pass correct lengths to keypad_send_key() staging: comedi: addi_apci_2032: fix interrupt support staging: comedi: addi_apci_2032: move i_APCI2032_ConfigDigitalOutput() ...
Diffstat (limited to 'drivers/iio/dac/ad5449.c')
-rw-r--r--drivers/iio/dac/ad5449.c376
1 files changed, 376 insertions, 0 deletions
diff --git a/drivers/iio/dac/ad5449.c b/drivers/iio/dac/ad5449.c
new file mode 100644
index 000000000000..0ee6f8eeba8d
--- /dev/null
+++ b/drivers/iio/dac/ad5449.c
@@ -0,0 +1,376 @@
+/*
+ * AD5415, AD5426, AD5429, AD5432, AD5439, AD5443, AD5449 Digital to Analog
+ * Converter driver.
+ *
+ * Copyright 2012 Analog Devices Inc.
+ * Author: Lars-Peter Clausen <lars@metafoo.de>
+ *
+ * Licensed under the GPL-2.
+ */
+
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/spi/spi.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
+#include <linux/regulator/consumer.h>
+#include <asm/unaligned.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+
+#include <linux/platform_data/ad5449.h>
+
+#define AD5449_MAX_CHANNELS 2
+#define AD5449_MAX_VREFS 2
+
+#define AD5449_CMD_NOOP 0x0
+#define AD5449_CMD_LOAD_AND_UPDATE(x) (0x1 + (x) * 3)
+#define AD5449_CMD_READ(x) (0x2 + (x) * 3)
+#define AD5449_CMD_LOAD(x) (0x3 + (x) * 3)
+#define AD5449_CMD_CTRL 13
+
+#define AD5449_CTRL_SDO_OFFSET 10
+#define AD5449_CTRL_DAISY_CHAIN BIT(9)
+#define AD5449_CTRL_HCLR_TO_MIDSCALE BIT(8)
+#define AD5449_CTRL_SAMPLE_RISING BIT(7)
+
+/**
+ * struct ad5449_chip_info - chip specific information
+ * @channels: Channel specification
+ * @num_channels: Number of channels
+ * @has_ctrl: Chip has a control register
+ */
+struct ad5449_chip_info {
+ const struct iio_chan_spec *channels;
+ unsigned int num_channels;
+ bool has_ctrl;
+};
+
+/**
+ * struct ad5449 - driver instance specific data
+ * @spi: the SPI device for this driver instance
+ * @chip_info: chip model specific constants, available modes etc
+ * @vref_reg: vref supply regulators
+ * @has_sdo: whether the SDO line is connected
+ * @dac_cache: Cache for the DAC values
+ * @data: spi transfer buffers
+ */
+struct ad5449 {
+ struct spi_device *spi;
+ const struct ad5449_chip_info *chip_info;
+ struct regulator_bulk_data vref_reg[AD5449_MAX_VREFS];
+
+ bool has_sdo;
+ uint16_t dac_cache[AD5449_MAX_CHANNELS];
+
+ /*
+ * DMA (thus cache coherency maintenance) requires the
+ * transfer buffers to live in their own cache lines.
+ */
+ __be16 data[2] ____cacheline_aligned;
+};
+
+enum ad5449_type {
+ ID_AD5426,
+ ID_AD5429,
+ ID_AD5432,
+ ID_AD5439,
+ ID_AD5443,
+ ID_AD5449,
+};
+
+static int ad5449_write(struct iio_dev *indio_dev, unsigned int addr,
+ unsigned int val)
+{
+ struct ad5449 *st = iio_priv(indio_dev);
+ int ret;
+
+ mutex_lock(&indio_dev->mlock);
+ st->data[0] = cpu_to_be16((addr << 12) | val);
+ ret = spi_write(st->spi, st->data, 2);
+ mutex_unlock(&indio_dev->mlock);
+
+ return ret;
+}
+
+static int ad5449_read(struct iio_dev *indio_dev, unsigned int addr,
+ unsigned int *val)
+{
+ struct ad5449 *st = iio_priv(indio_dev);
+ int ret;
+ struct spi_message msg;
+ struct spi_transfer t[] = {
+ {
+ .tx_buf = &st->data[0],
+ .len = 2,
+ .cs_change = 1,
+ }, {
+ .tx_buf = &st->data[1],
+ .rx_buf = &st->data[1],
+ .len = 2,
+ },
+ };
+
+ spi_message_init(&msg);
+ spi_message_add_tail(&t[0], &msg);
+ spi_message_add_tail(&t[1], &msg);
+
+ mutex_lock(&indio_dev->mlock);
+ st->data[0] = cpu_to_be16(addr << 12);
+ st->data[1] = cpu_to_be16(AD5449_CMD_NOOP);
+
+ ret = spi_sync(st->spi, &msg);
+ if (ret < 0)
+ goto out_unlock;
+
+ *val = be16_to_cpu(st->data[1]);
+
+out_unlock:
+ mutex_unlock(&indio_dev->mlock);
+ return ret;
+}
+
+static int ad5449_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan, int *val, int *val2, long info)
+{
+ struct ad5449 *st = iio_priv(indio_dev);
+ struct regulator_bulk_data *reg;
+ int scale_uv;
+ int ret;
+
+ switch (info) {
+ case IIO_CHAN_INFO_RAW:
+ if (st->has_sdo) {
+ ret = ad5449_read(indio_dev,
+ AD5449_CMD_READ(chan->address), val);
+ if (ret)
+ return ret;
+ *val &= 0xfff;
+ } else {
+ *val = st->dac_cache[chan->address];
+ }
+
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_SCALE:
+ reg = &st->vref_reg[chan->channel];
+ scale_uv = regulator_get_voltage(reg->consumer);
+ if (scale_uv < 0)
+ return scale_uv;
+
+ *val = scale_uv / 1000;
+ *val2 = chan->scan_type.realbits;
+
+ return IIO_VAL_FRACTIONAL_LOG2;
+ default:
+ break;
+ }
+
+ return -EINVAL;
+}
+
+static int ad5449_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan, int val, int val2, long info)
+{
+ struct ad5449 *st = iio_priv(indio_dev);
+ int ret;
+
+ switch (info) {
+ case IIO_CHAN_INFO_RAW:
+ if (val < 0 || val >= (1 << chan->scan_type.realbits))
+ return -EINVAL;
+
+ ret = ad5449_write(indio_dev,
+ AD5449_CMD_LOAD_AND_UPDATE(chan->address),
+ val << chan->scan_type.shift);
+ if (ret == 0)
+ st->dac_cache[chan->address] = val;
+ break;
+ default:
+ ret = -EINVAL;
+ }
+
+ return ret;
+}
+
+static const struct iio_info ad5449_info = {
+ .read_raw = ad5449_read_raw,
+ .write_raw = ad5449_write_raw,
+ .driver_module = THIS_MODULE,
+};
+
+#define AD5449_CHANNEL(chan, bits) { \
+ .type = IIO_VOLTAGE, \
+ .indexed = 1, \
+ .output = 1, \
+ .channel = (chan), \
+ .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT | \
+ IIO_CHAN_INFO_SCALE_SEPARATE_BIT, \
+ .address = (chan), \
+ .scan_type = IIO_ST('u', (bits), 16, 12 - (bits)), \
+}
+
+#define DECLARE_AD5449_CHANNELS(name, bits) \
+const struct iio_chan_spec name[] = { \
+ AD5449_CHANNEL(0, bits), \
+ AD5449_CHANNEL(1, bits), \
+}
+
+static DECLARE_AD5449_CHANNELS(ad5429_channels, 8);
+static DECLARE_AD5449_CHANNELS(ad5439_channels, 10);
+static DECLARE_AD5449_CHANNELS(ad5449_channels, 12);
+
+static const struct ad5449_chip_info ad5449_chip_info[] = {
+ [ID_AD5426] = {
+ .channels = ad5429_channels,
+ .num_channels = 1,
+ .has_ctrl = false,
+ },
+ [ID_AD5429] = {
+ .channels = ad5429_channels,
+ .num_channels = 2,
+ .has_ctrl = true,
+ },
+ [ID_AD5432] = {
+ .channels = ad5439_channels,
+ .num_channels = 1,
+ .has_ctrl = false,
+ },
+ [ID_AD5439] = {
+ .channels = ad5439_channels,
+ .num_channels = 2,
+ .has_ctrl = true,
+ },
+ [ID_AD5443] = {
+ .channels = ad5449_channels,
+ .num_channels = 1,
+ .has_ctrl = false,
+ },
+ [ID_AD5449] = {
+ .channels = ad5449_channels,
+ .num_channels = 2,
+ .has_ctrl = true,
+ },
+};
+
+static const char *ad5449_vref_name(struct ad5449 *st, int n)
+{
+ if (st->chip_info->num_channels == 1)
+ return "VREF";
+
+ if (n == 0)
+ return "VREFA";
+ else
+ return "VREFB";
+}
+
+static int __devinit ad5449_spi_probe(struct spi_device *spi)
+{
+ struct ad5449_platform_data *pdata = spi->dev.platform_data;
+ const struct spi_device_id *id = spi_get_device_id(spi);
+ struct iio_dev *indio_dev;
+ struct ad5449 *st;
+ unsigned int i;
+ int ret;
+
+ indio_dev = iio_device_alloc(sizeof(*st));
+ if (indio_dev == NULL)
+ return -ENOMEM;
+
+ st = iio_priv(indio_dev);
+ spi_set_drvdata(spi, indio_dev);
+
+ st->chip_info = &ad5449_chip_info[id->driver_data];
+ st->spi = spi;
+
+ for (i = 0; i < st->chip_info->num_channels; ++i)
+ st->vref_reg[i].supply = ad5449_vref_name(st, i);
+
+ ret = regulator_bulk_get(&spi->dev, st->chip_info->num_channels,
+ st->vref_reg);
+ if (ret)
+ goto error_free;
+
+ ret = regulator_bulk_enable(st->chip_info->num_channels, st->vref_reg);
+ if (ret)
+ goto error_free_reg;
+
+ indio_dev->dev.parent = &spi->dev;
+ indio_dev->name = id->name;
+ indio_dev->info = &ad5449_info;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->channels = st->chip_info->channels;
+ indio_dev->num_channels = st->chip_info->num_channels;
+
+ if (st->chip_info->has_ctrl) {
+ unsigned int ctrl = 0x00;
+ if (pdata) {
+ if (pdata->hardware_clear_to_midscale)
+ ctrl |= AD5449_CTRL_HCLR_TO_MIDSCALE;
+ ctrl |= pdata->sdo_mode << AD5449_CTRL_SDO_OFFSET;
+ st->has_sdo = pdata->sdo_mode != AD5449_SDO_DISABLED;
+ } else {
+ st->has_sdo = true;
+ }
+ ad5449_write(indio_dev, AD5449_CMD_CTRL, ctrl);
+ }
+
+ ret = iio_device_register(indio_dev);
+ if (ret)
+ goto error_disable_reg;
+
+ return 0;
+
+error_disable_reg:
+ regulator_bulk_disable(st->chip_info->num_channels, st->vref_reg);
+error_free_reg:
+ regulator_bulk_free(st->chip_info->num_channels, st->vref_reg);
+error_free:
+ iio_device_free(indio_dev);
+
+ return ret;
+}
+
+static int __devexit ad5449_spi_remove(struct spi_device *spi)
+{
+ struct iio_dev *indio_dev = spi_get_drvdata(spi);
+ struct ad5449 *st = iio_priv(indio_dev);
+
+ iio_device_unregister(indio_dev);
+
+ regulator_bulk_disable(st->chip_info->num_channels, st->vref_reg);
+ regulator_bulk_free(st->chip_info->num_channels, st->vref_reg);
+
+ iio_device_free(indio_dev);
+
+ return 0;
+}
+
+static const struct spi_device_id ad5449_spi_ids[] = {
+ { "ad5415", ID_AD5449 },
+ { "ad5426", ID_AD5426 },
+ { "ad5429", ID_AD5429 },
+ { "ad5432", ID_AD5432 },
+ { "ad5439", ID_AD5439 },
+ { "ad5443", ID_AD5443 },
+ { "ad5449", ID_AD5449 },
+ {}
+};
+MODULE_DEVICE_TABLE(spi, ad5449_spi_ids);
+
+static struct spi_driver ad5449_spi_driver = {
+ .driver = {
+ .name = "ad5449",
+ .owner = THIS_MODULE,
+ },
+ .probe = ad5449_spi_probe,
+ .remove = __devexit_p(ad5449_spi_remove),
+ .id_table = ad5449_spi_ids,
+};
+module_spi_driver(ad5449_spi_driver);
+
+MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
+MODULE_DESCRIPTION("Analog Devices AD5449 and similar DACs");
+MODULE_LICENSE("GPL v2");