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path: root/drivers/staging/iio/adc/ad7192.c
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Diffstat (limited to 'drivers/staging/iio/adc/ad7192.c')
-rw-r--r--drivers/staging/iio/adc/ad7192.c1184
1 files changed, 1184 insertions, 0 deletions
diff --git a/drivers/staging/iio/adc/ad7192.c b/drivers/staging/iio/adc/ad7192.c
new file mode 100644
index 000000000000..adf6d95dd34f
--- /dev/null
+++ b/drivers/staging/iio/adc/ad7192.c
@@ -0,0 +1,1184 @@
+/*
+ * AD7190 AD7192 AD7195 SPI ADC driver
+ *
+ * Copyright 2011 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2.
+ */
+
+#include <linux/interrupt.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
+#include <linux/spi/spi.h>
+#include <linux/regulator/consumer.h>
+#include <linux/err.h>
+#include <linux/sched.h>
+#include <linux/delay.h>
+
+#include "../iio.h"
+#include "../sysfs.h"
+#include "../ring_generic.h"
+#include "../ring_sw.h"
+#include "../trigger.h"
+#include "../trigger_consumer.h"
+
+#include "ad7192.h"
+
+/* Registers */
+#define AD7192_REG_COMM 0 /* Communications Register (WO, 8-bit) */
+#define AD7192_REG_STAT 0 /* Status Register (RO, 8-bit) */
+#define AD7192_REG_MODE 1 /* Mode Register (RW, 24-bit */
+#define AD7192_REG_CONF 2 /* Configuration Register (RW, 24-bit) */
+#define AD7192_REG_DATA 3 /* Data Register (RO, 24/32-bit) */
+#define AD7192_REG_ID 4 /* ID Register (RO, 8-bit) */
+#define AD7192_REG_GPOCON 5 /* GPOCON Register (RO, 8-bit) */
+#define AD7192_REG_OFFSET 6 /* Offset Register (RW, 16-bit
+ * (AD7792)/24-bit (AD7192)) */
+#define AD7192_REG_FULLSALE 7 /* Full-Scale Register
+ * (RW, 16-bit (AD7792)/24-bit (AD7192)) */
+
+/* Communications Register Bit Designations (AD7192_REG_COMM) */
+#define AD7192_COMM_WEN (1 << 7) /* Write Enable */
+#define AD7192_COMM_WRITE (0 << 6) /* Write Operation */
+#define AD7192_COMM_READ (1 << 6) /* Read Operation */
+#define AD7192_COMM_ADDR(x) (((x) & 0x7) << 3) /* Register Address */
+#define AD7192_COMM_CREAD (1 << 2) /* Continuous Read of Data Register */
+
+/* Status Register Bit Designations (AD7192_REG_STAT) */
+#define AD7192_STAT_RDY (1 << 7) /* Ready */
+#define AD7192_STAT_ERR (1 << 6) /* Error (Overrange, Underrange) */
+#define AD7192_STAT_NOREF (1 << 5) /* Error no external reference */
+#define AD7192_STAT_PARITY (1 << 4) /* Parity */
+#define AD7192_STAT_CH3 (1 << 2) /* Channel 3 */
+#define AD7192_STAT_CH2 (1 << 1) /* Channel 2 */
+#define AD7192_STAT_CH1 (1 << 0) /* Channel 1 */
+
+/* Mode Register Bit Designations (AD7192_REG_MODE) */
+#define AD7192_MODE_SEL(x) (((x) & 0x7) << 21) /* Operation Mode Select */
+#define AD7192_MODE_DAT_STA (1 << 20) /* Status Register transmission */
+#define AD7192_MODE_CLKSRC(x) (((x) & 0x3) << 18) /* Clock Source Select */
+#define AD7192_MODE_SINC3 (1 << 15) /* SINC3 Filter Select */
+#define AD7192_MODE_ACX (1 << 14) /* AC excitation enable(AD7195 only)*/
+#define AD7192_MODE_ENPAR (1 << 13) /* Parity Enable */
+#define AD7192_MODE_CLKDIV (1 << 12) /* Clock divide by 2 (AD7190/2 only)*/
+#define AD7192_MODE_SCYCLE (1 << 11) /* Single cycle conversion */
+#define AD7192_MODE_REJ60 (1 << 10) /* 50/60Hz notch filter */
+#define AD7192_MODE_RATE(x) ((x) & 0x3FF) /* Filter Update Rate Select */
+
+/* Mode Register: AD7192_MODE_SEL options */
+#define AD7192_MODE_CONT 0 /* Continuous Conversion Mode */
+#define AD7192_MODE_SINGLE 1 /* Single Conversion Mode */
+#define AD7192_MODE_IDLE 2 /* Idle Mode */
+#define AD7192_MODE_PWRDN 3 /* Power-Down Mode */
+#define AD7192_MODE_CAL_INT_ZERO 4 /* Internal Zero-Scale Calibration */
+#define AD7192_MODE_CAL_INT_FULL 5 /* Internal Full-Scale Calibration */
+#define AD7192_MODE_CAL_SYS_ZERO 6 /* System Zero-Scale Calibration */
+#define AD7192_MODE_CAL_SYS_FULL 7 /* System Full-Scale Calibration */
+
+/* Mode Register: AD7192_MODE_CLKSRC options */
+#define AD7192_CLK_EXT_MCLK1_2 0 /* External 4.92 MHz Clock connected
+ * from MCLK1 to MCLK2 */
+#define AD7192_CLK_EXT_MCLK2 1 /* External Clock applied to MCLK2 */
+#define AD7192_CLK_INT 2 /* Internal 4.92 MHz Clock not
+ * available at the MCLK2 pin */
+#define AD7192_CLK_INT_CO 3 /* Internal 4.92 MHz Clock available
+ * at the MCLK2 pin */
+
+
+/* Configuration Register Bit Designations (AD7192_REG_CONF) */
+
+#define AD7192_CONF_CHOP (1 << 23) /* CHOP enable */
+#define AD7192_CONF_REFSEL (1 << 20) /* REFIN1/REFIN2 Reference Select */
+#define AD7192_CONF_CHAN(x) (((x) & 0xFF) << 8) /* Channel select */
+#define AD7192_CONF_BURN (1 << 7) /* Burnout current enable */
+#define AD7192_CONF_REFDET (1 << 6) /* Reference detect enable */
+#define AD7192_CONF_BUF (1 << 4) /* Buffered Mode Enable */
+#define AD7192_CONF_UNIPOLAR (1 << 3) /* Unipolar/Bipolar Enable */
+#define AD7192_CONF_GAIN(x) ((x) & 0x7) /* Gain Select */
+
+#define AD7192_CH_AIN1P_AIN2M 0 /* AIN1(+) - AIN2(-) */
+#define AD7192_CH_AIN3P_AIN4M 1 /* AIN3(+) - AIN4(-) */
+#define AD7192_CH_TEMP 2 /* Temp Sensor */
+#define AD7192_CH_AIN2P_AIN2M 3 /* AIN2(+) - AIN2(-) */
+#define AD7192_CH_AIN1 4 /* AIN1 - AINCOM */
+#define AD7192_CH_AIN2 5 /* AIN2 - AINCOM */
+#define AD7192_CH_AIN3 6 /* AIN3 - AINCOM */
+#define AD7192_CH_AIN4 7 /* AIN4 - AINCOM */
+
+/* ID Register Bit Designations (AD7192_REG_ID) */
+#define ID_AD7190 0x4
+#define ID_AD7192 0x0
+#define ID_AD7195 0x6
+#define AD7192_ID_MASK 0x0F
+
+/* GPOCON Register Bit Designations (AD7192_REG_GPOCON) */
+#define AD7192_GPOCON_BPDSW (1 << 6) /* Bridge power-down switch enable */
+#define AD7192_GPOCON_GP32EN (1 << 5) /* Digital Output P3 and P2 enable */
+#define AD7192_GPOCON_GP10EN (1 << 4) /* Digital Output P1 and P0 enable */
+#define AD7192_GPOCON_P3DAT (1 << 3) /* P3 state */
+#define AD7192_GPOCON_P2DAT (1 << 2) /* P2 state */
+#define AD7192_GPOCON_P1DAT (1 << 1) /* P1 state */
+#define AD7192_GPOCON_P0DAT (1 << 0) /* P0 state */
+
+#define AD7192_INT_FREQ_MHz 4915200
+
+/* NOTE:
+ * The AD7190/2/5 features a dual use data out ready DOUT/RDY output.
+ * In order to avoid contentions on the SPI bus, it's therefore necessary
+ * to use spi bus locking.
+ *
+ * The DOUT/RDY output must also be wired to an interrupt capable GPIO.
+ */
+
+struct ad7192_state {
+ struct spi_device *spi;
+ struct iio_trigger *trig;
+ struct regulator *reg;
+ struct ad7192_platform_data *pdata;
+ wait_queue_head_t wq_data_avail;
+ bool done;
+ bool irq_dis;
+ u16 int_vref_mv;
+ u32 mclk;
+ u32 f_order;
+ u32 mode;
+ u32 conf;
+ u32 scale_avail[8][2];
+ u32 available_scan_masks[9];
+ u8 gpocon;
+ u8 devid;
+ /*
+ * DMA (thus cache coherency maintenance) requires the
+ * transfer buffers to live in their own cache lines.
+ */
+ u8 data[4] ____cacheline_aligned;
+};
+
+static int __ad7192_write_reg(struct ad7192_state *st, bool locked,
+ bool cs_change, unsigned char reg,
+ unsigned size, unsigned val)
+{
+ u8 *data = st->data;
+ struct spi_transfer t = {
+ .tx_buf = data,
+ .len = size + 1,
+ .cs_change = cs_change,
+ };
+ struct spi_message m;
+
+ data[0] = AD7192_COMM_WRITE | AD7192_COMM_ADDR(reg);
+
+ switch (size) {
+ case 3:
+ data[1] = val >> 16;
+ data[2] = val >> 8;
+ data[3] = val;
+ break;
+ case 2:
+ data[1] = val >> 8;
+ data[2] = val;
+ break;
+ case 1:
+ data[1] = val;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ spi_message_init(&m);
+ spi_message_add_tail(&t, &m);
+
+ if (locked)
+ return spi_sync_locked(st->spi, &m);
+ else
+ return spi_sync(st->spi, &m);
+}
+
+static int ad7192_write_reg(struct ad7192_state *st,
+ unsigned reg, unsigned size, unsigned val)
+{
+ return __ad7192_write_reg(st, false, false, reg, size, val);
+}
+
+static int __ad7192_read_reg(struct ad7192_state *st, bool locked,
+ bool cs_change, unsigned char reg,
+ int *val, unsigned size)
+{
+ u8 *data = st->data;
+ int ret;
+ struct spi_transfer t[] = {
+ {
+ .tx_buf = data,
+ .len = 1,
+ }, {
+ .rx_buf = data,
+ .len = size,
+ .cs_change = cs_change,
+ },
+ };
+ struct spi_message m;
+
+ data[0] = AD7192_COMM_READ | AD7192_COMM_ADDR(reg);
+
+ spi_message_init(&m);
+ spi_message_add_tail(&t[0], &m);
+ spi_message_add_tail(&t[1], &m);
+
+ if (locked)
+ ret = spi_sync_locked(st->spi, &m);
+ else
+ ret = spi_sync(st->spi, &m);
+
+ if (ret < 0)
+ return ret;
+
+ switch (size) {
+ case 3:
+ *val = data[0] << 16 | data[1] << 8 | data[2];
+ break;
+ case 2:
+ *val = data[0] << 8 | data[1];
+ break;
+ case 1:
+ *val = data[0];
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int ad7192_read_reg(struct ad7192_state *st,
+ unsigned reg, int *val, unsigned size)
+{
+ return __ad7192_read_reg(st, 0, 0, reg, val, size);
+}
+
+static int ad7192_read(struct ad7192_state *st, unsigned ch,
+ unsigned len, int *val)
+{
+ int ret;
+ st->conf = (st->conf & ~AD7192_CONF_CHAN(-1)) |
+ AD7192_CONF_CHAN(1 << ch);
+ st->mode = (st->mode & ~AD7192_MODE_SEL(-1)) |
+ AD7192_MODE_SEL(AD7192_MODE_SINGLE);
+
+ ad7192_write_reg(st, AD7192_REG_CONF, 3, st->conf);
+
+ spi_bus_lock(st->spi->master);
+ st->done = false;
+
+ ret = __ad7192_write_reg(st, 1, 1, AD7192_REG_MODE, 3, st->mode);
+ if (ret < 0)
+ goto out;
+
+ st->irq_dis = false;
+ enable_irq(st->spi->irq);
+ wait_event_interruptible(st->wq_data_avail, st->done);
+
+ ret = __ad7192_read_reg(st, 1, 0, AD7192_REG_DATA, val, len);
+out:
+ spi_bus_unlock(st->spi->master);
+
+ return ret;
+}
+
+static int ad7192_calibrate(struct ad7192_state *st, unsigned mode, unsigned ch)
+{
+ int ret;
+
+ st->conf = (st->conf & ~AD7192_CONF_CHAN(-1)) |
+ AD7192_CONF_CHAN(1 << ch);
+ st->mode = (st->mode & ~AD7192_MODE_SEL(-1)) | AD7192_MODE_SEL(mode);
+
+ ad7192_write_reg(st, AD7192_REG_CONF, 3, st->conf);
+
+ spi_bus_lock(st->spi->master);
+ st->done = false;
+
+ ret = __ad7192_write_reg(st, 1, 1, AD7192_REG_MODE, 3,
+ (st->devid != ID_AD7195) ?
+ st->mode | AD7192_MODE_CLKDIV :
+ st->mode);
+ if (ret < 0)
+ goto out;
+
+ st->irq_dis = false;
+ enable_irq(st->spi->irq);
+ wait_event_interruptible(st->wq_data_avail, st->done);
+
+ st->mode = (st->mode & ~AD7192_MODE_SEL(-1)) |
+ AD7192_MODE_SEL(AD7192_MODE_IDLE);
+
+ ret = __ad7192_write_reg(st, 1, 0, AD7192_REG_MODE, 3, st->mode);
+out:
+ spi_bus_unlock(st->spi->master);
+
+ return ret;
+}
+
+static const u8 ad7192_calib_arr[8][2] = {
+ {AD7192_MODE_CAL_INT_ZERO, AD7192_CH_AIN1},
+ {AD7192_MODE_CAL_INT_FULL, AD7192_CH_AIN1},
+ {AD7192_MODE_CAL_INT_ZERO, AD7192_CH_AIN2},
+ {AD7192_MODE_CAL_INT_FULL, AD7192_CH_AIN2},
+ {AD7192_MODE_CAL_INT_ZERO, AD7192_CH_AIN3},
+ {AD7192_MODE_CAL_INT_FULL, AD7192_CH_AIN3},
+ {AD7192_MODE_CAL_INT_ZERO, AD7192_CH_AIN4},
+ {AD7192_MODE_CAL_INT_FULL, AD7192_CH_AIN4}
+};
+
+static int ad7192_calibrate_all(struct ad7192_state *st)
+{
+ int i, ret;
+
+ for (i = 0; i < ARRAY_SIZE(ad7192_calib_arr); i++) {
+ ret = ad7192_calibrate(st, ad7192_calib_arr[i][0],
+ ad7192_calib_arr[i][1]);
+ if (ret)
+ goto out;
+ }
+
+ return 0;
+out:
+ dev_err(&st->spi->dev, "Calibration failed\n");
+ return ret;
+}
+
+static int ad7192_setup(struct ad7192_state *st)
+{
+ struct iio_dev *indio_dev = spi_get_drvdata(st->spi);
+ struct ad7192_platform_data *pdata = st->pdata;
+ unsigned long long scale_uv;
+ int i, ret, id;
+ u8 ones[6];
+
+ /* reset the serial interface */
+ memset(&ones, 0xFF, 6);
+ ret = spi_write(st->spi, &ones, 6);
+ if (ret < 0)
+ goto out;
+ msleep(1); /* Wait for at least 500us */
+
+ /* write/read test for device presence */
+ ret = ad7192_read_reg(st, AD7192_REG_ID, &id, 1);
+ if (ret)
+ goto out;
+
+ id &= AD7192_ID_MASK;
+
+ if (id != st->devid)
+ dev_warn(&st->spi->dev, "device ID query failed (0x%X)\n", id);
+
+ switch (pdata->clock_source_sel) {
+ case AD7192_CLK_EXT_MCLK1_2:
+ case AD7192_CLK_EXT_MCLK2:
+ st->mclk = AD7192_INT_FREQ_MHz;
+ break;
+ case AD7192_CLK_INT:
+ case AD7192_CLK_INT_CO:
+ if (pdata->ext_clk_Hz)
+ st->mclk = pdata->ext_clk_Hz;
+ else
+ st->mclk = AD7192_INT_FREQ_MHz;
+ break;
+ default:
+ ret = -EINVAL;
+ goto out;
+ }
+
+ st->mode = AD7192_MODE_SEL(AD7192_MODE_IDLE) |
+ AD7192_MODE_CLKSRC(pdata->clock_source_sel) |
+ AD7192_MODE_RATE(480);
+
+ st->conf = AD7192_CONF_GAIN(0);
+
+ if (pdata->rej60_en)
+ st->mode |= AD7192_MODE_REJ60;
+
+ if (pdata->sinc3_en)
+ st->mode |= AD7192_MODE_SINC3;
+
+ if (pdata->refin2_en && (st->devid != ID_AD7195))
+ st->conf |= AD7192_CONF_REFSEL;
+
+ if (pdata->chop_en) {
+ st->conf |= AD7192_CONF_CHOP;
+ if (pdata->sinc3_en)
+ st->f_order = 3; /* SINC 3rd order */
+ else
+ st->f_order = 4; /* SINC 4th order */
+ } else {
+ st->f_order = 1;
+ }
+
+ if (pdata->buf_en)
+ st->conf |= AD7192_CONF_BUF;
+
+ if (pdata->unipolar_en)
+ st->conf |= AD7192_CONF_UNIPOLAR;
+
+ if (pdata->burnout_curr_en)
+ st->conf |= AD7192_CONF_BURN;
+
+ ret = ad7192_write_reg(st, AD7192_REG_MODE, 3, st->mode);
+ if (ret)
+ goto out;
+
+ ret = ad7192_write_reg(st, AD7192_REG_CONF, 3, st->conf);
+ if (ret)
+ goto out;
+
+ ret = ad7192_calibrate_all(st);
+ if (ret)
+ goto out;
+
+ /* Populate available ADC input ranges */
+ for (i = 0; i < ARRAY_SIZE(st->scale_avail); i++) {
+ scale_uv = ((u64)st->int_vref_mv * 100000000)
+ >> (indio_dev->channels[0].scan_type.realbits -
+ ((st->conf & AD7192_CONF_UNIPOLAR) ? 0 : 1));
+ scale_uv >>= i;
+
+ st->scale_avail[i][1] = do_div(scale_uv, 100000000) * 10;
+ st->scale_avail[i][0] = scale_uv;
+ }
+
+ return 0;
+out:
+ dev_err(&st->spi->dev, "setup failed\n");
+ return ret;
+}
+
+static int ad7192_scan_from_ring(struct ad7192_state *st, unsigned ch, int *val)
+{
+ struct iio_ring_buffer *ring = iio_priv_to_dev(st)->ring;
+ int ret;
+ s64 dat64[2];
+ u32 *dat32 = (u32 *)dat64;
+
+ if (!(ring->scan_mask & (1 << ch)))
+ return -EBUSY;
+
+ ret = ring->access->read_last(ring, (u8 *) &dat64);
+ if (ret)
+ return ret;
+
+ *val = *dat32;
+
+ return 0;
+}
+
+static int ad7192_ring_preenable(struct iio_dev *indio_dev)
+{
+ struct ad7192_state *st = iio_priv(indio_dev);
+ struct iio_ring_buffer *ring = indio_dev->ring;
+ size_t d_size;
+ unsigned channel;
+
+ if (!ring->scan_count)
+ return -EINVAL;
+
+ channel = __ffs(ring->scan_mask);
+
+ d_size = ring->scan_count *
+ indio_dev->channels[0].scan_type.storagebits / 8;
+
+ if (ring->scan_timestamp) {
+ d_size += sizeof(s64);
+
+ if (d_size % sizeof(s64))
+ d_size += sizeof(s64) - (d_size % sizeof(s64));
+ }
+
+ if (indio_dev->ring->access->set_bytes_per_datum)
+ indio_dev->ring->access->set_bytes_per_datum(indio_dev->ring,
+ d_size);
+
+ st->mode = (st->mode & ~AD7192_MODE_SEL(-1)) |
+ AD7192_MODE_SEL(AD7192_MODE_CONT);
+ st->conf = (st->conf & ~AD7192_CONF_CHAN(-1)) |
+ AD7192_CONF_CHAN(1 << indio_dev->channels[channel].address);
+
+ ad7192_write_reg(st, AD7192_REG_CONF, 3, st->conf);
+
+ spi_bus_lock(st->spi->master);
+ __ad7192_write_reg(st, 1, 1, AD7192_REG_MODE, 3, st->mode);
+
+ st->irq_dis = false;
+ enable_irq(st->spi->irq);
+
+ return 0;
+}
+
+static int ad7192_ring_postdisable(struct iio_dev *indio_dev)
+{
+ struct ad7192_state *st = iio_priv(indio_dev);
+
+ st->mode = (st->mode & ~AD7192_MODE_SEL(-1)) |
+ AD7192_MODE_SEL(AD7192_MODE_IDLE);
+
+ st->done = false;
+ wait_event_interruptible(st->wq_data_avail, st->done);
+
+ if (!st->irq_dis)
+ disable_irq_nosync(st->spi->irq);
+
+ __ad7192_write_reg(st, 1, 0, AD7192_REG_MODE, 3, st->mode);
+
+ return spi_bus_unlock(st->spi->master);
+}
+
+/**
+ * ad7192_trigger_handler() bh of trigger launched polling to ring buffer
+ **/
+static irqreturn_t ad7192_trigger_handler(int irq, void *p)
+{
+ struct iio_poll_func *pf = p;
+ struct iio_dev *indio_dev = pf->indio_dev;
+ struct iio_ring_buffer *ring = indio_dev->ring;
+ struct ad7192_state *st = iio_priv(indio_dev);
+ s64 dat64[2];
+ s32 *dat32 = (s32 *)dat64;
+
+ if (ring->scan_count)
+ __ad7192_read_reg(st, 1, 1, AD7192_REG_DATA,
+ dat32,
+ indio_dev->channels[0].scan_type.realbits/8);
+
+ /* Guaranteed to be aligned with 8 byte boundary */
+ if (ring->scan_timestamp)
+ dat64[1] = pf->timestamp;
+
+ ring->access->store_to(ring, (u8 *)dat64, pf->timestamp);
+
+ iio_trigger_notify_done(indio_dev->trig);
+ st->irq_dis = false;
+ enable_irq(st->spi->irq);
+
+ return IRQ_HANDLED;
+}
+
+static const struct iio_ring_setup_ops ad7192_ring_setup_ops = {
+ .preenable = &ad7192_ring_preenable,
+ .postenable = &iio_triggered_ring_postenable,
+ .predisable = &iio_triggered_ring_predisable,
+ .postdisable = &ad7192_ring_postdisable,
+};
+
+static int ad7192_register_ring_funcs_and_init(struct iio_dev *indio_dev)
+{
+ int ret;
+
+ indio_dev->ring = iio_sw_rb_allocate(indio_dev);
+ if (!indio_dev->ring) {
+ ret = -ENOMEM;
+ goto error_ret;
+ }
+ /* Effectively select the ring buffer implementation */
+ indio_dev->ring->access = &ring_sw_access_funcs;
+ indio_dev->pollfunc = iio_alloc_pollfunc(&iio_pollfunc_store_time,
+ &ad7192_trigger_handler,
+ IRQF_ONESHOT,
+ indio_dev,
+ "ad7192_consumer%d",
+ indio_dev->id);
+ if (indio_dev->pollfunc == NULL) {
+ ret = -ENOMEM;
+ goto error_deallocate_sw_rb;
+ }
+
+ /* Ring buffer functions - here trigger setup related */
+ indio_dev->ring->setup_ops = &ad7192_ring_setup_ops;
+
+ /* Flag that polled ring buffering is possible */
+ indio_dev->modes |= INDIO_RING_TRIGGERED;
+ return 0;
+
+error_deallocate_sw_rb:
+ iio_sw_rb_free(indio_dev->ring);
+error_ret:
+ return ret;
+}
+
+static void ad7192_ring_cleanup(struct iio_dev *indio_dev)
+{
+ iio_dealloc_pollfunc(indio_dev->pollfunc);
+ iio_sw_rb_free(indio_dev->ring);
+}
+
+/**
+ * ad7192_data_rdy_trig_poll() the event handler for the data rdy trig
+ **/
+static irqreturn_t ad7192_data_rdy_trig_poll(int irq, void *private)
+{
+ struct ad7192_state *st = iio_priv(private);
+
+ st->done = true;
+ wake_up_interruptible(&st->wq_data_avail);
+ disable_irq_nosync(irq);
+ st->irq_dis = true;
+ iio_trigger_poll(st->trig, iio_get_time_ns());
+
+ return IRQ_HANDLED;
+}
+
+static int ad7192_probe_trigger(struct iio_dev *indio_dev)
+{
+ struct ad7192_state *st = iio_priv(indio_dev);
+ int ret;
+
+ st->trig = iio_allocate_trigger("%s-dev%d",
+ spi_get_device_id(st->spi)->name,
+ indio_dev->id);
+ if (st->trig == NULL) {
+ ret = -ENOMEM;
+ goto error_ret;
+ }
+
+ ret = request_irq(st->spi->irq,
+ ad7192_data_rdy_trig_poll,
+ IRQF_TRIGGER_LOW,
+ spi_get_device_id(st->spi)->name,
+ indio_dev);
+ if (ret)
+ goto error_free_trig;
+
+ disable_irq_nosync(st->spi->irq);
+ st->irq_dis = true;
+ st->trig->dev.parent = &st->spi->dev;
+ st->trig->owner = THIS_MODULE;
+ st->trig->private_data = indio_dev;
+
+ ret = iio_trigger_register(st->trig);
+
+ /* select default trigger */
+ indio_dev->trig = st->trig;
+ if (ret)
+ goto error_free_irq;
+
+ return 0;
+
+error_free_irq:
+ free_irq(st->spi->irq, indio_dev);
+error_free_trig:
+ iio_free_trigger(st->trig);
+error_ret:
+ return ret;
+}
+
+static void ad7192_remove_trigger(struct iio_dev *indio_dev)
+{
+ struct ad7192_state *st = iio_priv(indio_dev);
+
+ iio_trigger_unregister(st->trig);
+ free_irq(st->spi->irq, indio_dev);
+ iio_free_trigger(st->trig);
+}
+
+static ssize_t ad7192_read_frequency(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+ struct ad7192_state *st = iio_priv(indio_dev);
+
+ return sprintf(buf, "%d\n", st->mclk /
+ (st->f_order * 1024 * AD7192_MODE_RATE(st->mode)));
+}
+
+static ssize_t ad7192_write_frequency(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf,
+ size_t len)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+ struct ad7192_state *st = iio_priv(indio_dev);
+ unsigned long lval;
+ int div, ret;
+
+ ret = strict_strtoul(buf, 10, &lval);
+ if (ret)
+ return ret;
+
+ mutex_lock(&indio_dev->mlock);
+ if (iio_ring_enabled(indio_dev)) {
+ mutex_unlock(&indio_dev->mlock);
+ return -EBUSY;
+ }
+
+ div = st->mclk / (lval * st->f_order * 1024);
+ if (div < 1 || div > 1023) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ st->mode &= ~AD7192_MODE_RATE(-1);
+ st->mode |= AD7192_MODE_RATE(div);
+ ad7192_write_reg(st, AD7192_REG_MODE, 3, st->mode);
+
+out:
+ mutex_unlock(&indio_dev->mlock);
+
+ return ret ? ret : len;
+}
+
+static IIO_DEV_ATTR_SAMP_FREQ(S_IWUSR | S_IRUGO,
+ ad7192_read_frequency,
+ ad7192_write_frequency);
+
+
+static ssize_t ad7192_show_scale_available(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+ struct ad7192_state *st = iio_priv(indio_dev);
+ int i, len = 0;
+
+ for (i = 0; i < ARRAY_SIZE(st->scale_avail); i++)
+ len += sprintf(buf + len, "%d.%09u ", st->scale_avail[i][0],
+ st->scale_avail[i][1]);
+
+ len += sprintf(buf + len, "\n");
+
+ return len;
+}
+
+static IIO_DEVICE_ATTR_NAMED(in_m_in_scale_available, in-in_scale_available,
+ S_IRUGO, ad7192_show_scale_available, NULL, 0);
+
+static IIO_DEVICE_ATTR(in_scale_available, S_IRUGO,
+ ad7192_show_scale_available, NULL, 0);
+
+static ssize_t ad7192_show_ac_excitation(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+ struct ad7192_state *st = iio_priv(indio_dev);
+
+ return sprintf(buf, "%d\n", !!(st->mode & AD7192_MODE_ACX));
+}
+
+static ssize_t ad7192_show_bridge_switch(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+ struct ad7192_state *st = iio_priv(indio_dev);
+
+ return sprintf(buf, "%d\n", !!(st->gpocon & AD7192_GPOCON_BPDSW));
+}
+
+static ssize_t ad7192_set(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf,
+ size_t len)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+ struct ad7192_state *st = iio_priv(indio_dev);
+ struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+ int ret;
+ bool val;
+
+ ret = strtobool(buf, &val);
+ if (ret < 0)
+ return ret;
+
+ mutex_lock(&indio_dev->mlock);
+ if (iio_ring_enabled(indio_dev)) {
+ mutex_unlock(&indio_dev->mlock);
+ return -EBUSY;
+ }
+
+ switch (this_attr->address) {
+ case AD7192_REG_GPOCON:
+ if (val)
+ st->gpocon |= AD7192_GPOCON_BPDSW;
+ else
+ st->gpocon &= ~AD7192_GPOCON_BPDSW;
+
+ ad7192_write_reg(st, AD7192_REG_GPOCON, 1, st->gpocon);
+ break;
+ case AD7192_REG_MODE:
+ if (val)
+ st->mode |= AD7192_MODE_ACX;
+ else
+ st->mode &= ~AD7192_MODE_ACX;
+
+ ad7192_write_reg(st, AD7192_REG_GPOCON, 3, st->mode);
+ break;
+ default:
+ ret = -EINVAL;
+ }
+
+ mutex_unlock(&indio_dev->mlock);
+
+ return ret ? ret : len;
+}
+
+static IIO_DEVICE_ATTR(bridge_switch_en, S_IRUGO | S_IWUSR,
+ ad7192_show_bridge_switch, ad7192_set,
+ AD7192_REG_GPOCON);
+
+static IIO_DEVICE_ATTR(ac_excitation_en, S_IRUGO | S_IWUSR,
+ ad7192_show_ac_excitation, ad7192_set,
+ AD7192_REG_MODE);
+
+static struct attribute *ad7192_attributes[] = {
+ &iio_dev_attr_sampling_frequency.dev_attr.attr,
+ &iio_dev_attr_in_m_in_scale_available.dev_attr.attr,
+ &iio_dev_attr_in_scale_available.dev_attr.attr,
+ &iio_dev_attr_bridge_switch_en.dev_attr.attr,
+ &iio_dev_attr_ac_excitation_en.dev_attr.attr,
+ NULL
+};
+
+static mode_t ad7192_attr_is_visible(struct kobject *kobj,
+ struct attribute *attr, int n)
+{
+ struct device *dev = container_of(kobj, struct device, kobj);
+ struct iio_dev *dev_info = dev_get_drvdata(dev);
+ struct ad7192_state *st = iio_priv(dev_info);
+
+ mode_t mode = attr->mode;
+
+ if ((st->devid != ID_AD7195) &&
+ (attr == &iio_dev_attr_ac_excitation_en.dev_attr.attr))
+ mode = 0;
+
+ return mode;
+}
+
+static const struct attribute_group ad7192_attribute_group = {
+ .attrs = ad7192_attributes,
+ .is_visible = ad7192_attr_is_visible,
+};
+
+static int ad7192_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val,
+ int *val2,
+ long m)
+{
+ struct ad7192_state *st = iio_priv(indio_dev);
+ int ret, smpl = 0;
+ bool unipolar = !!(st->conf & AD7192_CONF_UNIPOLAR);
+
+ switch (m) {
+ case 0:
+ mutex_lock(&indio_dev->mlock);
+ if (iio_ring_enabled(indio_dev))
+ ret = ad7192_scan_from_ring(st,
+ chan->scan_index, &smpl);
+ else
+ ret = ad7192_read(st, chan->address,
+ chan->scan_type.realbits / 8, &smpl);
+ mutex_unlock(&indio_dev->mlock);
+
+ if (ret < 0)
+ return ret;
+
+ *val = (smpl >> chan->scan_type.shift) &
+ ((1 << (chan->scan_type.realbits)) - 1);
+
+ switch (chan->type) {
+ case IIO_IN:
+ case IIO_IN_DIFF:
+ if (!unipolar)
+ *val -= (1 << (chan->scan_type.realbits - 1));
+ break;
+ case IIO_TEMP:
+ *val -= 0x800000;
+ *val /= 2815; /* temp Kelvin */
+ *val -= 273; /* temp Celsius */
+ break;
+ default:
+ return -EINVAL;
+ }
+ return IIO_VAL_INT;
+
+ case (1 << IIO_CHAN_INFO_SCALE_SHARED):
+ mutex_lock(&indio_dev->mlock);
+ *val = st->scale_avail[AD7192_CONF_GAIN(st->conf)][0];
+ *val2 = st->scale_avail[AD7192_CONF_GAIN(st->conf)][1];
+ mutex_unlock(&indio_dev->mlock);
+
+ return IIO_VAL_INT_PLUS_NANO;
+
+ case (1 << IIO_CHAN_INFO_SCALE_SEPARATE):
+ *val = 1000;
+
+ return IIO_VAL_INT;
+ }
+
+ return -EINVAL;
+}
+
+static int ad7192_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val,
+ int val2,
+ long mask)
+{
+ struct ad7192_state *st = iio_priv(indio_dev);
+ int ret, i;
+ unsigned int tmp;
+
+ mutex_lock(&indio_dev->mlock);
+ if (iio_ring_enabled(indio_dev)) {
+ mutex_unlock(&indio_dev->mlock);
+ return -EBUSY;
+ }
+
+ switch (mask) {
+ case (1 << IIO_CHAN_INFO_SCALE_SHARED):
+ ret = -EINVAL;
+ for (i = 0; i < ARRAY_SIZE(st->scale_avail); i++)
+ if (val2 == st->scale_avail[i][1]) {
+ tmp = st->conf;
+ st->conf &= ~AD7192_CONF_GAIN(-1);
+ st->conf |= AD7192_CONF_GAIN(i);
+
+ if (tmp != st->conf) {
+ ad7192_write_reg(st, AD7192_REG_CONF,
+ 3, st->conf);
+ ad7192_calibrate_all(st);
+ }
+ ret = 0;
+ }
+
+ default:
+ ret = -EINVAL;
+ }
+
+ mutex_unlock(&indio_dev->mlock);
+
+ return ret;
+}
+
+static int ad7192_validate_trigger(struct iio_dev *indio_dev,
+ struct iio_trigger *trig)
+{
+ if (indio_dev->trig != trig)
+ return -EINVAL;
+
+ return 0;
+}
+
+static int ad7192_write_raw_get_fmt(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ long mask)
+{
+ return IIO_VAL_INT_PLUS_NANO;
+}
+
+static const struct iio_info ad7192_info = {
+ .read_raw = &ad7192_read_raw,
+ .write_raw = &ad7192_write_raw,
+ .write_raw_get_fmt = &ad7192_write_raw_get_fmt,
+ .attrs = &ad7192_attribute_group,
+ .validate_trigger = ad7192_validate_trigger,
+ .driver_module = THIS_MODULE,
+};
+
+#define AD7192_CHAN_DIFF(_chan, _chan2, _name, _address, _si) \
+ { .type = IIO_IN_DIFF, \
+ .indexed = 1, \
+ .extend_name = _name, \
+ .channel = _chan, \
+ .channel2 = _chan2, \
+ .info_mask = (1 << IIO_CHAN_INFO_SCALE_SHARED), \
+ .address = _address, \
+ .scan_index = _si, \
+ .scan_type = IIO_ST('s', 24, 32, 0)}
+
+#define AD7192_CHAN(_chan, _address, _si) \
+ { .type = IIO_IN, \
+ .indexed = 1, \
+ .channel = _chan, \
+ .info_mask = (1 << IIO_CHAN_INFO_SCALE_SHARED), \
+ .address = _address, \
+ .scan_index = _si, \
+ .scan_type = IIO_ST('s', 24, 32, 0)}
+
+#define AD7192_CHAN_TEMP(_chan, _address, _si) \
+ { .type = IIO_TEMP, \
+ .indexed = 1, \
+ .channel = _chan, \
+ .info_mask = (1 << IIO_CHAN_INFO_SCALE_SEPARATE), \
+ .address = _address, \
+ .scan_index = _si, \
+ .scan_type = IIO_ST('s', 24, 32, 0)}
+
+static struct iio_chan_spec ad7192_channels[] = {
+ AD7192_CHAN_DIFF(1, 2, NULL, AD7192_CH_AIN1P_AIN2M, 0),
+ AD7192_CHAN_DIFF(3, 4, NULL, AD7192_CH_AIN3P_AIN4M, 1),
+ AD7192_CHAN_TEMP(0, AD7192_CH_TEMP, 2),
+ AD7192_CHAN_DIFF(2, 2, "shorted", AD7192_CH_AIN2P_AIN2M, 3),
+ AD7192_CHAN(1, AD7192_CH_AIN1, 4),
+ AD7192_CHAN(2, AD7192_CH_AIN2, 5),
+ AD7192_CHAN(3, AD7192_CH_AIN3, 6),
+ AD7192_CHAN(4, AD7192_CH_AIN4, 7),
+ IIO_CHAN_SOFT_TIMESTAMP(8),
+};
+
+static int __devinit ad7192_probe(struct spi_device *spi)
+{
+ struct ad7192_platform_data *pdata = spi->dev.platform_data;
+ struct ad7192_state *st;
+ struct iio_dev *indio_dev;
+ int ret, i , voltage_uv = 0, regdone = 0;
+
+ if (!pdata) {
+ dev_err(&spi->dev, "no platform data?\n");
+ return -ENODEV;
+ }
+
+ if (!spi->irq) {
+ dev_err(&spi->dev, "no IRQ?\n");
+ return -ENODEV;
+ }
+
+ indio_dev = iio_allocate_device(sizeof(*st));
+ if (indio_dev == NULL)
+ return -ENOMEM;
+
+ st = iio_priv(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->pdata = pdata;
+
+ if (pdata && pdata->vref_mv)
+ st->int_vref_mv = pdata->vref_mv;
+ else if (voltage_uv)
+ st->int_vref_mv = voltage_uv / 1000;
+ else
+ dev_warn(&spi->dev, "reference voltage undefined\n");
+
+ spi_set_drvdata(spi, indio_dev);
+ st->spi = spi;
+ st->devid = spi_get_device_id(spi)->driver_data;
+ indio_dev->dev.parent = &spi->dev;
+ indio_dev->name = spi_get_device_id(spi)->name;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->channels = ad7192_channels;
+ indio_dev->num_channels = ARRAY_SIZE(ad7192_channels);
+ indio_dev->available_scan_masks = st->available_scan_masks;
+ indio_dev->info = &ad7192_info;
+
+ for (i = 0; i < indio_dev->num_channels; i++)
+ st->available_scan_masks[i] = (1 << i) | (1 <<
+ indio_dev->channels[indio_dev->num_channels - 1].
+ scan_index);
+
+ init_waitqueue_head(&st->wq_data_avail);
+
+ ret = ad7192_register_ring_funcs_and_init(indio_dev);
+ if (ret)
+ goto error_disable_reg;
+
+ ret = iio_device_register(indio_dev);
+ if (ret)
+ goto error_unreg_ring;
+ regdone = 1;
+
+ ret = ad7192_probe_trigger(indio_dev);
+ if (ret)
+ goto error_unreg_ring;
+
+ ret = iio_ring_buffer_register_ex(indio_dev->ring, 0,
+ indio_dev->channels,
+ indio_dev->num_channels);
+ if (ret)
+ goto error_remove_trigger;
+
+ ret = ad7192_setup(st);
+ if (ret)
+ goto error_uninitialize_ring;
+
+ return 0;
+
+error_uninitialize_ring:
+ iio_ring_buffer_unregister(indio_dev->ring);
+error_remove_trigger:
+ ad7192_remove_trigger(indio_dev);
+error_unreg_ring:
+ ad7192_ring_cleanup(indio_dev);
+error_disable_reg:
+ if (!IS_ERR(st->reg))
+ regulator_disable(st->reg);
+error_put_reg:
+ if (!IS_ERR(st->reg))
+ regulator_put(st->reg);
+
+ if (regdone)
+ iio_device_unregister(indio_dev);
+ else
+ iio_free_device(indio_dev);
+
+ return ret;
+}
+
+static int ad7192_remove(struct spi_device *spi)
+{
+ struct iio_dev *indio_dev = spi_get_drvdata(spi);
+ struct ad7192_state *st = iio_priv(indio_dev);
+
+ iio_ring_buffer_unregister(indio_dev->ring);
+ ad7192_remove_trigger(indio_dev);
+ ad7192_ring_cleanup(indio_dev);
+
+ if (!IS_ERR(st->reg)) {
+ regulator_disable(st->reg);
+ regulator_put(st->reg);
+ }
+
+ iio_device_unregister(indio_dev);
+
+ return 0;
+}
+
+static const struct spi_device_id ad7192_id[] = {
+ {"ad7190", ID_AD7190},
+ {"ad7192", ID_AD7192},
+ {"ad7195", ID_AD7195},
+ {}
+};
+
+static struct spi_driver ad7192_driver = {
+ .driver = {
+ .name = "ad7192",
+ .owner = THIS_MODULE,
+ },
+ .probe = ad7192_probe,
+ .remove = __devexit_p(ad7192_remove),
+ .id_table = ad7192_id,
+};
+
+static int __init ad7192_init(void)
+{
+ return spi_register_driver(&ad7192_driver);
+}
+module_init(ad7192_init);
+
+static void __exit ad7192_exit(void)
+{
+ spi_unregister_driver(&ad7192_driver);
+}
+module_exit(ad7192_exit);
+
+MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
+MODULE_DESCRIPTION("Analog Devices AD7190, AD7192, AD7195 ADC");
+MODULE_LICENSE("GPL v2");