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authorLinus Torvalds <torvalds@linux-foundation.org>2012-07-26 18:14:49 (GMT)
committerLinus Torvalds <torvalds@linux-foundation.org>2012-07-26 18:14:49 (GMT)
commitb13bc8dda81c54a66a1c84e66f60b8feba659f28 (patch)
tree100a26eada424fa5d9b0e5eaaf4e23b8fa036fc8 /drivers/iio/dac/ad5686.c
parent9fc377799bc9bfd8d5cb35d0d1ea2e2458cbdbb3 (diff)
parent419e9266884fa853179ab726c27a63a9d3ae46e3 (diff)
downloadlinux-fsl-qoriq-b13bc8dda81c54a66a1c84e66f60b8feba659f28.tar.xz
Merge tag 'staging-3.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
Pull staging tree patches from Greg Kroah-Hartman: "Here's the big staging tree merge for the 3.6-rc1 merge window. There are some patches in here outside of drivers/staging/, notibly the iio code (which is still stradeling the staging / not staging boundry), the pstore code, and the tracing code. All of these have gotten acks from the various subsystem maintainers to be included in this tree. The pstore and tracing patches are related, and are coming here as they replace one of the android staging drivers. Otherwise, the normal staging mess. Lots of cleanups and a few new drivers (some iio drivers, and the large csr wireless driver abomination.) Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>" Fixed up trivial conflicts in drivers/staging/comedi/drivers/s626.h and drivers/staging/gdm72xx/netlink_k.c * tag 'staging-3.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (1108 commits) staging: csr: delete a bunch of unused library functions staging: csr: remove csr_utf16.c staging: csr: remove csr_pmem.h staging: csr: remove CsrPmemAlloc staging: csr: remove CsrPmemFree() staging: csr: remove CsrMemAllocDma() staging: csr: remove CsrMemCalloc() staging: csr: remove CsrMemAlloc() staging: csr: remove CsrMemFree() and CsrMemFreeDma() staging: csr: remove csr_util.h staging: csr: remove CsrOffSetOf() stating: csr: remove unneeded #includes in csr_util.c staging: csr: make CsrUInt16ToHex static staging: csr: remove CsrMemCpy() staging: csr: remove CsrStrLen() staging: csr: remove CsrVsnprintf() staging: csr: remove CsrStrDup staging: csr: remove CsrStrChr() staging: csr: remove CsrStrNCmp staging: csr: remove CsrStrCmp ...
Diffstat (limited to 'drivers/iio/dac/ad5686.c')
-rw-r--r--drivers/iio/dac/ad5686.c418
1 files changed, 418 insertions, 0 deletions
diff --git a/drivers/iio/dac/ad5686.c b/drivers/iio/dac/ad5686.c
new file mode 100644
index 0000000..6948d75
--- /dev/null
+++ b/drivers/iio/dac/ad5686.c
@@ -0,0 +1,418 @@
+/*
+ * AD5686R, AD5685R, AD5684R Digital to analog converters driver
+ *
+ * Copyright 2011 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2.
+ */
+
+#include <linux/interrupt.h>
+#include <linux/fs.h>
+#include <linux/device.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 <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+
+#define AD5686_DAC_CHANNELS 4
+
+#define AD5686_ADDR(x) ((x) << 16)
+#define AD5686_CMD(x) ((x) << 20)
+
+#define AD5686_ADDR_DAC(chan) (0x1 << (chan))
+#define AD5686_ADDR_ALL_DAC 0xF
+
+#define AD5686_CMD_NOOP 0x0
+#define AD5686_CMD_WRITE_INPUT_N 0x1
+#define AD5686_CMD_UPDATE_DAC_N 0x2
+#define AD5686_CMD_WRITE_INPUT_N_UPDATE_N 0x3
+#define AD5686_CMD_POWERDOWN_DAC 0x4
+#define AD5686_CMD_LDAC_MASK 0x5
+#define AD5686_CMD_RESET 0x6
+#define AD5686_CMD_INTERNAL_REFER_SETUP 0x7
+#define AD5686_CMD_DAISY_CHAIN_ENABLE 0x8
+#define AD5686_CMD_READBACK_ENABLE 0x9
+
+#define AD5686_LDAC_PWRDN_NONE 0x0
+#define AD5686_LDAC_PWRDN_1K 0x1
+#define AD5686_LDAC_PWRDN_100K 0x2
+#define AD5686_LDAC_PWRDN_3STATE 0x3
+
+/**
+ * struct ad5686_chip_info - chip specific information
+ * @int_vref_mv: AD5620/40/60: the internal reference voltage
+ * @channel: channel specification
+*/
+
+struct ad5686_chip_info {
+ u16 int_vref_mv;
+ struct iio_chan_spec channel[AD5686_DAC_CHANNELS];
+};
+
+/**
+ * struct ad5446_state - driver instance specific data
+ * @spi: spi_device
+ * @chip_info: chip model specific constants, available modes etc
+ * @reg: supply regulator
+ * @vref_mv: actual reference voltage used
+ * @pwr_down_mask: power down mask
+ * @pwr_down_mode: current power down mode
+ * @data: spi transfer buffers
+ */
+
+struct ad5686_state {
+ struct spi_device *spi;
+ const struct ad5686_chip_info *chip_info;
+ struct regulator *reg;
+ unsigned short vref_mv;
+ unsigned pwr_down_mask;
+ unsigned pwr_down_mode;
+ /*
+ * DMA (thus cache coherency maintenance) requires the
+ * transfer buffers to live in their own cache lines.
+ */
+
+ union {
+ u32 d32;
+ u8 d8[4];
+ } data[3] ____cacheline_aligned;
+};
+
+/**
+ * ad5686_supported_device_ids:
+ */
+
+enum ad5686_supported_device_ids {
+ ID_AD5684,
+ ID_AD5685,
+ ID_AD5686,
+};
+static int ad5686_spi_write(struct ad5686_state *st,
+ u8 cmd, u8 addr, u16 val, u8 shift)
+{
+ val <<= shift;
+
+ st->data[0].d32 = cpu_to_be32(AD5686_CMD(cmd) |
+ AD5686_ADDR(addr) |
+ val);
+
+ return spi_write(st->spi, &st->data[0].d8[1], 3);
+}
+
+static int ad5686_spi_read(struct ad5686_state *st, u8 addr)
+{
+ struct spi_transfer t[] = {
+ {
+ .tx_buf = &st->data[0].d8[1],
+ .len = 3,
+ .cs_change = 1,
+ }, {
+ .tx_buf = &st->data[1].d8[1],
+ .rx_buf = &st->data[2].d8[1],
+ .len = 3,
+ },
+ };
+ struct spi_message m;
+ int ret;
+
+ spi_message_init(&m);
+ spi_message_add_tail(&t[0], &m);
+ spi_message_add_tail(&t[1], &m);
+
+ st->data[0].d32 = cpu_to_be32(AD5686_CMD(AD5686_CMD_READBACK_ENABLE) |
+ AD5686_ADDR(addr));
+ st->data[1].d32 = cpu_to_be32(AD5686_CMD(AD5686_CMD_NOOP));
+
+ ret = spi_sync(st->spi, &m);
+ if (ret < 0)
+ return ret;
+
+ return be32_to_cpu(st->data[2].d32);
+}
+
+static const char * const ad5686_powerdown_modes[] = {
+ "1kohm_to_gnd",
+ "100kohm_to_gnd",
+ "three_state"
+};
+
+static int ad5686_get_powerdown_mode(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan)
+{
+ struct ad5686_state *st = iio_priv(indio_dev);
+
+ return ((st->pwr_down_mode >> (chan->channel * 2)) & 0x3) - 1;
+}
+
+static int ad5686_set_powerdown_mode(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan, unsigned int mode)
+{
+ struct ad5686_state *st = iio_priv(indio_dev);
+
+ st->pwr_down_mode &= ~(0x3 << (chan->channel * 2));
+ st->pwr_down_mode |= ((mode + 1) << (chan->channel * 2));
+
+ return 0;
+}
+
+static const struct iio_enum ad5686_powerdown_mode_enum = {
+ .items = ad5686_powerdown_modes,
+ .num_items = ARRAY_SIZE(ad5686_powerdown_modes),
+ .get = ad5686_get_powerdown_mode,
+ .set = ad5686_set_powerdown_mode,
+};
+
+static ssize_t ad5686_read_dac_powerdown(struct iio_dev *indio_dev,
+ uintptr_t private, const struct iio_chan_spec *chan, char *buf)
+{
+ struct ad5686_state *st = iio_priv(indio_dev);
+
+ return sprintf(buf, "%d\n", !!(st->pwr_down_mask &
+ (0x3 << (chan->channel * 2))));
+}
+
+static ssize_t ad5686_write_dac_powerdown(struct iio_dev *indio_dev,
+ uintptr_t private, const struct iio_chan_spec *chan, const char *buf,
+ size_t len)
+{
+ bool readin;
+ int ret;
+ struct ad5686_state *st = iio_priv(indio_dev);
+
+ ret = strtobool(buf, &readin);
+ if (ret)
+ return ret;
+
+ if (readin == true)
+ st->pwr_down_mask |= (0x3 << (chan->channel * 2));
+ else
+ st->pwr_down_mask &= ~(0x3 << (chan->channel * 2));
+
+ ret = ad5686_spi_write(st, AD5686_CMD_POWERDOWN_DAC, 0,
+ st->pwr_down_mask & st->pwr_down_mode, 0);
+
+ return ret ? ret : len;
+}
+
+static int ad5686_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val,
+ int *val2,
+ long m)
+{
+ struct ad5686_state *st = iio_priv(indio_dev);
+ unsigned long scale_uv;
+ int ret;
+
+ switch (m) {
+ case IIO_CHAN_INFO_RAW:
+ mutex_lock(&indio_dev->mlock);
+ ret = ad5686_spi_read(st, chan->address);
+ mutex_unlock(&indio_dev->mlock);
+ if (ret < 0)
+ return ret;
+ *val = ret;
+ return IIO_VAL_INT;
+ break;
+ case IIO_CHAN_INFO_SCALE:
+ scale_uv = (st->vref_mv * 100000)
+ >> (chan->scan_type.realbits);
+ *val = scale_uv / 100000;
+ *val2 = (scale_uv % 100000) * 10;
+ return IIO_VAL_INT_PLUS_MICRO;
+
+ }
+ return -EINVAL;
+}
+
+static int ad5686_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val,
+ int val2,
+ long mask)
+{
+ struct ad5686_state *st = iio_priv(indio_dev);
+ int ret;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ if (val > (1 << chan->scan_type.realbits) || val < 0)
+ return -EINVAL;
+
+ mutex_lock(&indio_dev->mlock);
+ ret = ad5686_spi_write(st,
+ AD5686_CMD_WRITE_INPUT_N_UPDATE_N,
+ chan->address,
+ val,
+ chan->scan_type.shift);
+ mutex_unlock(&indio_dev->mlock);
+ break;
+ default:
+ ret = -EINVAL;
+ }
+
+ return ret;
+}
+
+static const struct iio_info ad5686_info = {
+ .read_raw = ad5686_read_raw,
+ .write_raw = ad5686_write_raw,
+ .driver_module = THIS_MODULE,
+};
+
+static const struct iio_chan_spec_ext_info ad5686_ext_info[] = {
+ {
+ .name = "powerdown",
+ .read = ad5686_read_dac_powerdown,
+ .write = ad5686_write_dac_powerdown,
+ },
+ IIO_ENUM("powerdown_mode", false, &ad5686_powerdown_mode_enum),
+ IIO_ENUM_AVAILABLE("powerdown_mode", &ad5686_powerdown_mode_enum),
+ { },
+};
+
+#define AD5868_CHANNEL(chan, bits, shift) { \
+ .type = IIO_VOLTAGE, \
+ .indexed = 1, \
+ .output = 1, \
+ .channel = chan, \
+ .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT | \
+ IIO_CHAN_INFO_SCALE_SHARED_BIT, \
+ .address = AD5686_ADDR_DAC(chan), \
+ .scan_type = IIO_ST('u', bits, 16, shift), \
+ .ext_info = ad5686_ext_info, \
+}
+
+static const struct ad5686_chip_info ad5686_chip_info_tbl[] = {
+ [ID_AD5684] = {
+ .channel[0] = AD5868_CHANNEL(0, 12, 4),
+ .channel[1] = AD5868_CHANNEL(1, 12, 4),
+ .channel[2] = AD5868_CHANNEL(2, 12, 4),
+ .channel[3] = AD5868_CHANNEL(3, 12, 4),
+ .int_vref_mv = 2500,
+ },
+ [ID_AD5685] = {
+ .channel[0] = AD5868_CHANNEL(0, 14, 2),
+ .channel[1] = AD5868_CHANNEL(1, 14, 2),
+ .channel[2] = AD5868_CHANNEL(2, 14, 2),
+ .channel[3] = AD5868_CHANNEL(3, 14, 2),
+ .int_vref_mv = 2500,
+ },
+ [ID_AD5686] = {
+ .channel[0] = AD5868_CHANNEL(0, 16, 0),
+ .channel[1] = AD5868_CHANNEL(1, 16, 0),
+ .channel[2] = AD5868_CHANNEL(2, 16, 0),
+ .channel[3] = AD5868_CHANNEL(3, 16, 0),
+ .int_vref_mv = 2500,
+ },
+};
+
+
+static int __devinit ad5686_probe(struct spi_device *spi)
+{
+ struct ad5686_state *st;
+ struct iio_dev *indio_dev;
+ int ret, regdone = 0, voltage_uv = 0;
+
+ 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->reg = regulator_get(&spi->dev, "vcc");
+ if (!IS_ERR(st->reg)) {
+ ret = regulator_enable(st->reg);
+ if (ret)
+ goto error_put_reg;
+
+ voltage_uv = regulator_get_voltage(st->reg);
+ }
+
+ st->chip_info =
+ &ad5686_chip_info_tbl[spi_get_device_id(spi)->driver_data];
+
+ if (voltage_uv)
+ st->vref_mv = voltage_uv / 1000;
+ else
+ st->vref_mv = st->chip_info->int_vref_mv;
+
+ st->spi = spi;
+
+ /* Set all the power down mode for all channels to 1K pulldown */
+ st->pwr_down_mode = 0x55;
+
+ indio_dev->dev.parent = &spi->dev;
+ indio_dev->name = spi_get_device_id(spi)->name;
+ indio_dev->info = &ad5686_info;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->channels = st->chip_info->channel;
+ indio_dev->num_channels = AD5686_DAC_CHANNELS;
+
+ regdone = 1;
+ ret = ad5686_spi_write(st, AD5686_CMD_INTERNAL_REFER_SETUP, 0,
+ !!voltage_uv, 0);
+ if (ret)
+ goto error_disable_reg;
+
+ ret = iio_device_register(indio_dev);
+ if (ret)
+ goto error_disable_reg;
+
+ return 0;
+
+error_disable_reg:
+ if (!IS_ERR(st->reg))
+ regulator_disable(st->reg);
+error_put_reg:
+ if (!IS_ERR(st->reg))
+ regulator_put(st->reg);
+
+ iio_device_free(indio_dev);
+
+ return ret;
+}
+
+static int __devexit ad5686_remove(struct spi_device *spi)
+{
+ struct iio_dev *indio_dev = spi_get_drvdata(spi);
+ struct ad5686_state *st = iio_priv(indio_dev);
+
+ iio_device_unregister(indio_dev);
+ if (!IS_ERR(st->reg)) {
+ regulator_disable(st->reg);
+ regulator_put(st->reg);
+ }
+ iio_device_free(indio_dev);
+
+ return 0;
+}
+
+static const struct spi_device_id ad5686_id[] = {
+ {"ad5684", ID_AD5684},
+ {"ad5685", ID_AD5685},
+ {"ad5686", ID_AD5686},
+ {}
+};
+MODULE_DEVICE_TABLE(spi, ad5686_id);
+
+static struct spi_driver ad5686_driver = {
+ .driver = {
+ .name = "ad5686",
+ .owner = THIS_MODULE,
+ },
+ .probe = ad5686_probe,
+ .remove = __devexit_p(ad5686_remove),
+ .id_table = ad5686_id,
+};
+module_spi_driver(ad5686_driver);
+
+MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
+MODULE_DESCRIPTION("Analog Devices AD5686/85/84 DAC");
+MODULE_LICENSE("GPL v2");