Re: [PATCH] IIO: ADC: New driver for AD7190/AD7192/AD7195 4 Channel SPI ADC

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 08/12/2011 03:44 PM, Jonathan Cameron wrote:
On 08/12/11 13:41, michael.hennerich@xxxxxxxxxx wrote:
From: Michael Hennerich<michael.hennerich@xxxxxxxxxx>

New driver for AD7190/AD7192/AD7195 4.8 kHz, Ultralow Noise, 24-Bit
Sigma-Delta ADC with PGA

These devices features a dual use data out ready DOUT/RDY output.
In order to avoid contentions on the SPI bus, it's necessary to use
spi bus locking. The DOUT/RDY output must also be wired to an
interrupt capable GPIO.

In INDIO_RING_TRIGGERED mode, this driver may block its SPI bus segment
for an extended period of time.
Couple of nit picks and some missing docs.  Otherwise looks good.
Signed-off-by: Michael Hennerich<michael.hennerich@xxxxxxxxxx>
---
  drivers/staging/iio/adc/Kconfig  |   14 +
  drivers/staging/iio/adc/Makefile |    1 +
  drivers/staging/iio/adc/ad7192.c | 1178 ++++++++++++++++++++++++++++++++++++++
  drivers/staging/iio/adc/ad7192.h |   47 ++
  4 files changed, 1240 insertions(+), 0 deletions(-)
  create mode 100644 drivers/staging/iio/adc/ad7192.c
  create mode 100644 drivers/staging/iio/adc/ad7192.h

diff --git a/drivers/staging/iio/adc/Kconfig b/drivers/staging/iio/adc/Kconfig
index b39f2e1..975a9a5 100644
--- a/drivers/staging/iio/adc/Kconfig
+++ b/drivers/staging/iio/adc/Kconfig
@@ -161,6 +161,20 @@ config AD7816
         Say yes here to build support for Analog Devices AD7816/7/8
         temperature sensors and ADC.

+config AD7192
+     tristate "Analog Devices AD7190 AD7192 AD7195 ADC driver"
+     depends on SPI
+     select IIO_RING_BUFFER
+     select IIO_SW_RING
+     select IIO_TRIGGER
+     help
+       Say yes here to build support for Analog Devices AD7190,
+       AD7192 or AD7195 SPI analog to digital convertors (ADC).
+       If unsure, say N (but it's safe to say "Y").
+
+       To compile this driver as a module, choose M here: the
+       module will be called ad7192.
+
  config ADT75
       tristate "Analog Devices ADT75 temperature sensor driver"
       depends on I2C
diff --git a/drivers/staging/iio/adc/Makefile b/drivers/staging/iio/adc/Makefile
index f020351..b72dcd9 100644
--- a/drivers/staging/iio/adc/Makefile
+++ b/drivers/staging/iio/adc/Makefile
@@ -37,6 +37,7 @@ obj-$(CONFIG_AD7745) += ad7745.o
  obj-$(CONFIG_AD7780) += ad7780.o
  obj-$(CONFIG_AD7793) += ad7793.o
  obj-$(CONFIG_AD7816) += ad7816.o
+obj-$(CONFIG_AD7192) += ad7192.o
  obj-$(CONFIG_ADT75) += adt75.o
  obj-$(CONFIG_ADT7310) += adt7310.o
  obj-$(CONFIG_ADT7410) += adt7410.o
diff --git a/drivers/staging/iio/adc/ad7192.c b/drivers/staging/iio/adc/ad7192.c
new file mode 100644
index 0000000..e7e53d2
--- /dev/null
+++ b/drivers/staging/iio/adc/ad7192.c
@@ -0,0 +1,1178 @@
+/*
+ * 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 "adc.h"
Going... and unused anyway.
+
+#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 AD7190/2/5sold features a dual use data out ready DOUT/RDY output.
sold?
typo...
+ * 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.
+      */
I may be missing something but this seems somewhat large.
leftover from some debug test - 4 bytes are sufficient.

+     u8                              data[32] ____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
Inconsistent spacing in comments.
+                     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));
   That ternary operator looks weird.  is that not just !(st->conf&  AD7192_UNIPOLAR) ?
needless !! only...
In unipolar operation the we have 2^N, in bipolar it's 2^(N-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
+ **/
Unwanted blank line?
+
+static irqreturn_t ad7192_trigger_handler(int irq, void *p)
+{
+     struct iio_poll_func *pf = p;
+     struct iio_dev *indio_dev = pf->private_data;
+     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)
+{
+     /* ensure that the trigger has been detached */
+     if (indio_dev->trig) {
+             iio_put_trigger(indio_dev->trig);
+             iio_trigger_dettach_poll_func(indio_dev->trig,
+                                           indio_dev->pollfunc);
+     }
+     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);
+
For readability I'd just break this into two functions.
ok
+static ssize_t ad7192_show(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);
+     struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+
+     return sprintf(buf, "%d\n", (this_attr->address == AD7192_REG_GPOCON) ?
+             !!(st->gpocon&  AD7192_GPOCON_BPDSW) :
+             !!(st->mode&  AD7192_MODE_ACX));
+}
+
+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, ad7192_set,
+                    AD7192_REG_GPOCON);
+
+static IIO_DEVICE_ATTR(ac_excitation_en, S_IRUGO | S_IWUSR,
+                    ad7192_show, 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,
Docs please.
+&iio_dev_attr_ac_excitation_en.dev_attr.attr,
Docs please.
ok
+     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;
+
Could in theory hit a race between reading and writing this (and get inconsistent
pair of val and val2?)
ok - lets protect it by mutex.
+     case (1<<  IIO_CHAN_INFO_SCALE_SHARED):
+             *val = st->scale_avail[AD7192_CONF_GAIN(st->conf)][0];
+             *val2 = st->scale_avail[AD7192_CONF_GAIN(st->conf)][1];
+
+             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);
blank line here.
+     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,
+};
+
+static struct iio_chan_spec ad7192_channels[] = {
+
Peronsally I'm going more and more against this macro, so
if you are bored, please define a local one setting up
exactly those bits of the structure needed.  Its a little
more code, but a heck of a lot more readable. (basically
I was wrong to introduce this in the first place and will
not be taking it out of staging if I can help it!)

ok
+     IIO_CHAN(IIO_IN_DIFF, 0, 1, 0, NULL, 1, 2,
+                 (1<<  IIO_CHAN_INFO_SCALE_SHARED),
+                 AD7192_CH_AIN1P_AIN2M,
+                 0, IIO_ST('s', 24, 32, 0), 0),
+     IIO_CHAN(IIO_IN_DIFF, 0, 1, 0, NULL, 3, 4,
+                 (1<<  IIO_CHAN_INFO_SCALE_SHARED),
+                 AD7192_CH_AIN3P_AIN4M,
+                 1, IIO_ST('s', 24, 32, 0), 0),
+     IIO_CHAN(IIO_TEMP, 0, 1, 0, NULL, 0, 0,
+                 (1<<  IIO_CHAN_INFO_SCALE_SEPARATE),
+                 AD7192_CH_TEMP,
+                 2, IIO_ST('s', 24, 32, 0), 0),
+     IIO_CHAN(IIO_IN_DIFF, 0, 1, 0, "shorted", 2, 2,
+                 (1<<  IIO_CHAN_INFO_SCALE_SHARED),
+                 AD7192_CH_AIN2P_AIN2M,
+                 3, IIO_ST('s', 24, 32, 0), 0),
+     IIO_CHAN(IIO_IN, 0, 1, 0, NULL, 1, 0,
+                 (1<<  IIO_CHAN_INFO_SCALE_SHARED),
+                 AD7192_CH_AIN1,
+                 4, IIO_ST('s', 24, 32, 0), 0),
+     IIO_CHAN(IIO_IN, 0, 1, 0, NULL, 2, 0,
+                 (1<<  IIO_CHAN_INFO_SCALE_SHARED),
+                 AD7192_CH_AIN2,
+                 5, IIO_ST('s', 24, 32, 0), 0),
+     IIO_CHAN(IIO_IN, 0, 1, 0, NULL, 3, 0,
+                 (1<<  IIO_CHAN_INFO_SCALE_SHARED),
+                 AD7192_CH_AIN3,
+                 6, IIO_ST('s', 24, 32, 0), 0),
+     IIO_CHAN(IIO_IN, 0, 1, 0, NULL, 4, 0,
+                 (1<<  IIO_CHAN_INFO_SCALE_SHARED),
+                 AD7192_CH_AIN4,
+                 7, IIO_ST('s', 24, 32, 0), 0),
+     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;
Hmm..
Anything bad here?
+
+     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},
tab in next line?
+{}
+};
+
+static struct spi_driver ad7192_driver = {
+     .driver = {
+             .name   = "ad7192",
+             .bus    =&spi_bus_type,
This is set in spi_register_driver, so why set it here? (basically
have I missed an upcoming change in the spi core?)
indeed needless
+             .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@xxxxxxxxxxxxxxxxxxxx>");
+MODULE_DESCRIPTION("Analog Devices AD7190, AD7192, AD7195 ADC");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/staging/iio/adc/ad7192.h b/drivers/staging/iio/adc/ad7192.h
new file mode 100644
index 0000000..2e0bd5e
--- /dev/null
+++ b/drivers/staging/iio/adc/ad7192.h
@@ -0,0 +1,47 @@
+/*
+ * AD7190 AD7192 AD7195 SPI ADC driver
+ *
+ * Copyright 2011 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2.
+ */
+#ifndef IIO_ADC_AD7192_H_
+#define IIO_ADC_AD7192_H_
+
+/*
+ * TODO: struct ad7192_platform_data needs to go into include/linux/iio
+ */
+
+/**
+ * struct ad7192_platform_data - platform/board specific information
+ * @vref_mv:         the external reference voltage in millivolt
+ * @ext_clk_Hz:              the external clock frequency in Hz, if not set
+ *                   the driver uses the internal clock (16.776 MHz)
+ * @clock_source_sel:        [0..3]
+ *                   0 External 4.92 MHz clock connected from MCLK1 to MCLK2
+ *                   1 External Clock applied to MCLK2
+ *                   2 Internal 4.92 MHz Clock not available at the MCLK2 pin
+ *                   3 Internal 4.92 MHz Clock available at the MCLK2 pin
+ * @refin2_en:               REFIN1/REFIN2 Reference Select (AD7190/2 only)
+ * @rej60_en:                50/60Hz notch filter enable
+ * @sinc3_en:                SINC3 filter enable (default SINC4)
+ * @chop_en:         CHOP mode enable
+ * @buf_en:          buffered input mode enable
+ * @unipolar_en:     unipolar mode enable
+ * @burnout_curr_en: constant current generators on AIN(+|-) enable
+ */
+
+struct ad7192_platform_data {
+     u16             vref_mv;
+     u32             ext_clk_Hz;
Trivial, but reorder this to the top to save 2 bytes.
ok
+     u8              clock_source_sel;
+     bool            refin2_en;
+     bool            rej60_en;
+     bool            sinc3_en;
+     bool            chop_en;
+     bool            buf_en;
+     bool            unipolar_en;
+     bool            burnout_curr_en;
+};
+
+#endif /* IIO_ADC_AD7192_H_ */


Thanks for the review!

--
Greetings,
Michael

--
Analog Devices GmbH      Wilhelm-Wagenfeld-Str. 6      80807 Muenchen
Sitz der Gesellschaft: Muenchen; Registergericht: Muenchen HRB 40368;
Geschaeftsfuehrer:Dr.Carsten Suckrow, Thomas Wessel, William A. Martin,
Margaret Seif


--
To unsubscribe from this list: send the line "unsubscribe linux-iio" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html


[Index of Archives]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite News]     [Linux Input]     [Linux Kernel]     [Linux SCSI]     [X.org]

  Powered by Linux