px4-firmware/nuttx/drivers/analog/pga11x.c

794 lines
23 KiB
C

/****************************************************************************
* drivers/analog/pga11x.c
*
* Copyright (C) 2012 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* References:
* "PGA112, PGA113, PGA116, PGA117: Zerø-Drift PROGRAMMABLE GAIN AMPLIFIER
* with MUX", SBOS424B, March 2008, Revised September 2008, Texas
* Instruments Incorporated"
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <assert.h>
#include <errno.h>
#include <debug.h>
#include <nuttx/analog/pga11x.h>
#if defined(CONFIG_ADC) && defined(CONFIG_ADC_PGA11X)
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* The PGA112/PGA113 have a three-wire SPI digital interface; the
* PGA116/PGA117 have a four-wire SPI digital interface. The PGA116/117 also
* have daisy-chain capability (The PGA112/PGA113 can be used as the last device
* in a daisy-chain as shown if write-only communication is acceptable).
*/
/* PGA11x commands (PGA112/PGA113) */
#define PGA11X_CMD_READ 0x6a00
#define PGA11X_CMD_WRITE 0x2a00
#define PGA11X_CMD_NOOP 0x0000
#define PGA11X_CMD_SDN_DIS 0xe100
#define PGA11X_CMD_SDN_EN 0xe1f1
/* SPI Daisy-Chain Commands (PGA116/PGA117) */
#define PGA11X_DCCMD_SELECTOR 0x8000
#define PGA11X_DCCMD_NOOP (PGA11X_DCCMD_SELECTOR | PGA11X_CMD_NOOP)
#define PGA11X_DCCMD_SDN_DIS (PGA11X_DCCMD_SELECTOR | PGA11X_CMD_SDN_DIS)
#define PGA11X_DCCMD_SDN_EN (PGA11X_DCCMD_SELECTOR | PGA11X_CMD_SDN_EN)
#define PGA11X_DCCMD_READ (PGA11X_DCCMD_SELECTOR | PGA11X_CMD_READ)
#define PGA11X_DCCMD_WRITE (PGA11X_DCCMD_SELECTOR | PGA11X_CMD_WRITE)
/* Write command Gain Selection Bits (PGA112/PGA113)
*
* the PGA112 and PGA116 provide binary gain selections (1, 2, 4, 8, 16, 32,
* 64, 128); the PGA113 and PGA117 provide scope gain selections (1, 2, 5, 10,
* 20, 50, 100, 200).
*/
#define PGA11X_GAIN_SHIFT (4) /* Bits 4-7: Gain Selection Bits */
#define PGA11X_GAIN_MASK (15 << PGA11X_GAIN_SHIFT)
/* Write command Mux Channel Selection Bits
*
* The PGA112/PGA113 have a two-channel input MUX; the PGA116/PGA117 have a
* 10-channel input MUX.
*/
#define PGA11X_CHAN_SHIFT (0) /* Bits 0-3: Channel Selection Bits */
#define PGA11X_CHAN_MASK (15 << PGA11X_CHAN_SHIFT)
/* Other definitions ********************************************************/
#define SPI_DUMMY 0xff
/* Debug ********************************************************************/
/* Check if (non-standard) SPI debug is enabled */
#ifndef CONFIG_DEBUG
# undef CONFIG_DEBUG_VERBOSE
# undef CONFIG_DEBUG_SPI
#endif
#ifdef CONFIG_DEBUG_SPI
# define spidbg dbg
# ifdef CONFIG_DEBUG_VERBOSE
# define spivdbg dbg
# else
# define spivdbg(x...)
# endif
#else
# define spidbg(x...)
# define spivdbg(x...)
#endif
/****************************************************************************
* Private Types
****************************************************************************/
/****************************************************************************
* Private Data
****************************************************************************/
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: pga11x_configure
*
* Description:
* Configure the SPI bus as needed for the PGA11x device.
*
* Returned Value:
* None
*
****************************************************************************/
static void pga11x_configure(FAR struct spi_dev_s *spi)
{
spivdbg("MODE: %d BITS: 8 Frequency: %d\n",
CONFIG_PGA11X_SPIMODE, CONFIG_PGA11X_SPIFREQUENCY);
/* Call the setfrequency, setbits, and setmode methods to make sure that
* the SPI is properly configured for the device.
*/
SPI_SETMODE(spi, CONFIG_PGA11X_SPIMODE);
SPI_SETBITS(spi, 8);
(void)SPI_SETFREQUENCY(spi, CONFIG_PGA11X_SPIFREQUENCY);
}
/****************************************************************************
* Name: pga11x_lock
*
* Description:
* Lock the SPI bus and configure it as needed for the PGA11x device.
*
* Returned Value:
* None
*
****************************************************************************/
#ifndef CONFIG_SPI_OWNBUS
static void pga11x_lock(FAR struct spi_dev_s *spi)
{
spivdbg("Locking\n");
/* On SPI busses where there are multiple devices, it will be necessary to
* lock SPI to have exclusive access to the busses for a sequence of
* transfers. The bus should be locked before the chip is selected.
*
* This is a blocking call and will not return until we have exclusiv access to
* the SPI buss. We will retain that exclusive access until the bus is unlocked.
*/
SPI_LOCK(spi, true);
/* After locking the SPI bus, the we also need call the setfrequency, setbits, and
* setmode methods to make sure that the SPI is properly configured for the device.
* If the SPI buss is being shared, then it may have been left in an incompatible
* state.
*/
pga11x_configure(spi);
}
#else
# define pga11x_lock(spi)
#endif
/****************************************************************************
* Name: pga11x_unlock
*
* Description:
* Lock the SPI bus and configure it as needed for the PGA11x device.
*
* Returned Value:
* None
*
****************************************************************************/
#ifndef CONFIG_SPI_OWNBUS
static inline void pga11x_unlock(FAR struct spi_dev_s *spi)
{
spivdbg("Unlocking\n");
SPI_LOCK(spi, false);
}
#else
# define pga11x_unlock(spi)
#endif
/****************************************************************************
* Name: pga11x_send16
*
* Description:
* Send 16 bits of data, ignoring any returned data
*
* Input Parameters:
* spi - PGA11X driver instance
* word - The data to send
*
* Returned Value:
* None
*
* Assumptions:
* The bus is locked and the device is selected
*
****************************************************************************/
static void pga11x_send16(FAR struct spi_dev_s *spi, uint16_t word)
{
spivdbg("Send %04x\n", word);
/* The logical interface is 16-bits wide. However, this driver uses a
* 8-bit configuration for greaer portability.
*
* Send the MS byte first. Then the LS byte.
*/
SPI_SEND(spi, word >> 8);
SPI_SEND(spi, word & 0xff);
}
/****************************************************************************
* Name: pga11x_recv16
*
* Description:
* Receive 16 bits of data.
*
* Input Parameters:
* spi - PGA11X driver instance
*
* Returned Value:
* The received 16-bit value
*
* Assumptions:
* The bus is locked and the device is selected
*
****************************************************************************/
static uint16_t pga11x_recv16(FAR struct spi_dev_s *spi)
{
uint8_t msb;
uint8_t lsb;
/* The logical interface is 16-bits wide. However, this driver uses a
* 8-bit configuration for greaer portability.
*
* Send a dummy byte and receive MS byte first. Then the LS byte.
*/
msb = SPI_SEND(spi, SPI_DUMMY);
lsb = SPI_SEND(spi, SPI_DUMMY);
spivdbg("Received %02x %02x\n", msb, lsb);
return ((uint16_t)msb << 8) | (uint16_t)lsb;
}
/****************************************************************************
* Name: pga11x_write
*
* Description:
* Send a 16-bit command.
*
* Input Parameters:
* spi - PGA11X driver instance
* cmd - PGA11X command (non-daisy chained)
* u1cmd - PGA11X U1 command (daisy chained)
* u2cmd - PGA11X U2 command (daisy chained)
*
* Returned Value:
* The received 16-bit value
*
* Assumptions:
* The device is NOT selected and the NOT bus is locked.
*
****************************************************************************/
#ifndef CONFIG_PGA11X_DAISYCHAIN
static void pga11x_write(FAR struct spi_dev_s *spi, uint16_t cmd)
{
spivdbg("cmd %04x\n", cmd);
/* Lock, select, send the 16-bit command, de-select, and un-lock. */
pga11x_lock(spi);
SPI_SELECT(spi, SPIDEV_MUX, true);
pga11x_send16(spi, cmd);
SPI_SELECT(spi, SPIDEV_MUX, false);
pga11x_unlock(spi);
}
#else
static void pga11x_write(FAR struct spi_dev_s *spi, uint16_t u1cmd, uint16_t u2cmd)
{
spivdbg("U1 cmd: %04x U2 cmd: %04x\n", u1cmd, u2cmd);
/* Lock, select, send the U2 16-bit command, the U1 16-bit command, de-select,
* and un-lock.
*/
pga11x_lock(spi);
SPI_SELECT(spi, SPIDEV_MUX, true);
pga11x_send16(spi, u2cmd);
pga11x_send16(spi, u1cmd);
SPI_SELECT(spi, SPIDEV_MUX, false);
pga11x_unlock(spi);
}
#endif
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: pga11x_initialize
*
* Description:
* Initialize the PGA117 amplifier/multiplexer(s).
*
* Input Parameters:
* spi - An SPI "bottom half" device driver instance
*
* Returned Value:
* On success, a non-NULL opaque handle is returned; a NULL is returned
* on any failure. This handle may be used with the other PGA117 interface
* functions to control the multiplexer
*
****************************************************************************/
PGA11X_HANDLE pga11x_initialize(FAR struct spi_dev_s *spi)
{
spivdbg("Entry\n");
/* Configure the SPI us for the device. Do this now only if the PGA11X is
* the only device on the bus.
*/
#ifdef CONFIG_SPI_OWNBUS
pga11x_configure(spi);
#endif
/* No other special state is required, just return the SPI driver instance
* as the handle. This gives us a place to extend functionality in the
* future if neccessary.
*/
return (PGA11X_HANDLE)spi;
}
/****************************************************************************
* Name: pga11x_select
*
* Description:
* Select an input channel and gain for all PGA11xs.
*
* If CONFIG_PGA11X_DAISYCHAIN is defined, then pga11x_select() configures
* both chips in the daisy-chain. pga11x_uselect() is provided to support
* configuring the parts in the daisychain independently.
*
* Input Parameters:
* spi - An SPI "bottom half" device driver instance
* settings - New channel and gain settings
*
* Returned Value:
* Zero on sucess; a negated errno value on failure.
*
****************************************************************************/
int pga11x_select(PGA11X_HANDLE handle,
FAR const struct pga11x_settings_s *settings)
{
#ifndef CONFIG_PGA11X_DAISYCHAIN
FAR struct spi_dev_s *spi = (FAR struct spi_dev_s *)handle;
uint16_t cmd;
DEBUGASSERT(handle && settings);
spivdbg("channel: %d gain: %d\n", settings->channel, settings->gain);
/* Format the command */
cmd = PGA11X_CMD_WRITE |
((uint16_t)settings->channel << PGA11X_CHAN_SHIFT) |
((uint16_t)settings->gain << PGA11X_GAIN_SHIFT);
/* Send the command */
pga11x_write(spi, cmd);
return OK;
#else
FAR struct spi_dev_s *spi = (FAR struct spi_dev_s *)handle;
uint16_t u1cmd;
uint16_t u2cmd;
DEBUGASSERT(handle && settings);
spivdbg("U1 channel: %d gain: %d\n", settings->u1.channel, settings->u1.gain);
spivdbg("U1 channel: %d gain: %d\n", settings->u1.channel, settings->u1.gain);
/* Format the commands */
u1cmd = PGA11X_CMD_WRITE |
((uint16_t)settings->u1.channel << PGA11X_CHAN_SHIFT) |
((uint16_t)settings->u1.gain << PGA11X_GAIN_SHIFT);
u2cmd = PGA11X_DCCMD_WRITE |
((uint16_t)settings->u2.channel << PGA11X_CHAN_SHIFT) |
((uint16_t)settings->u2.gain << PGA11X_GAIN_SHIFT);
/* Send the command */
pga11x_write(spi, u1cmd, u2cmd);
return OK;
#endif
}
/****************************************************************************
* Name: pga11x_uselect
*
* Description:
* Select an input channel and gain for one PGA11x.
*
* If CONFIG_PGA11X_DAISYCHAIN is defined, then pga11x_uselect() configures
* one chips in the daisy-chain.
*
* Input Parameters:
* spi - An SPI "bottom half" device driver instance
* pos - Position of the chip in the daisy chain (0 or 1)
* settings - New channel and gain settings
*
* Returned Value:
* Zero on sucess; a negated errno value on failure.
*
****************************************************************************/
#ifdef CONFIG_PGA11X_DAISYCHAIN
int pga11x_uselect(PGA11X_HANDLE handle, int pos,
FAR const struct pga11x_usettings_s *settings)
{
FAR struct spi_dev_s *spi = (FAR struct spi_dev_s *)handle;
uint16_t u1cmd;
uint16_t u2cmd;
spivdbg("channel: %d gain: %d\n", settings->channel, settings->gain);
DEBUGASSERT(handle);
/* Format the commands */
if (pos == 0)
{
u1cmd = PGA11X_CMD_WRITE |
((uint16_t)settings->channel << PGA11X_CHAN_SHIFT) |
((uint16_t)settings->gain << PGA11X_GAIN_SHIFT);
u2cmd = PGA11X_DCCMD_NOOP;
}
else /* if (pos == 1) */
{
u1cmd = PGA11X_CMD_NOOP;
u2cmd = PGA11X_DCCMD_WRITE |
((uint16_t)settings->channel << PGA11X_CHAN_SHIFT) |
((uint16_t)settings->gain << PGA11X_GAIN_SHIFT);
}
/* Send the command */
pga11x_write(spi, u1cmd, u2cmd);
return OK;
}
#endif
/****************************************************************************
* Name: pga11x_read
*
* Description:
* Read from all PGA117 amplifier/multiplexers.
*
* If CONFIG_PGA11X_DAISYCHAIN is defined, then pga11x_read() reads from
* both chips in the daisy-chain. pga11x_uread() is provided to support
* accessing the parts independently.
*
* Input Parameters:
* spi - An SPI "bottom half" device driver instance
* settings - Returned channel and gain settings
*
* Returned Value:
* Zero on sucess; a negated errno value on failure.
*
****************************************************************************/
int pga11x_read(PGA11X_HANDLE handle, FAR struct pga11x_settings_s *settings)
{
#ifdef CONFIG_PGA11X_DAISYCHAIN
FAR struct spi_dev_s *spi = (FAR struct spi_dev_s *)handle;
uint16_t u1value;
uint16_t u2value;
spivdbg("Entry\n");
DEBUGASSERT(handle && settings);
/* Lock the bus and read the configuration */
pga11x_lock(spi);
/* Select, send the 16-bit command, the 16-bit daisy-chain command, and
* then de-select the part. I do not know if de-selection between word
* transfers is required. However, it is shown in the timing diagrams
* for the part.
*/
SPI_SELECT(spi, SPIDEV_MUX, true);
pga11x_send16(spi, PGA11X_CMD_READ);
pga11x_send16(spi, PGA11X_DCCMD_READ);
SPI_SELECT(spi, SPIDEV_MUX, false);
/* Re-select, get the returned values, de-select, and unlock */
SPI_SELECT(spi, SPIDEV_MUX, true);
u2value = pga11x_recv16(spi);
u1value = pga11x_recv16(spi);
SPI_SELECT(spi, SPIDEV_MUX, false);
pga11x_unlock(spi);
/* Decode the returned value */
spivdbg("Returning %04x %04x\n", u2value, u1value);
settings->u1.channel = (uint8_t)((u1value & PGA11X_CHAN_MASK) >> PGA11X_CHAN_SHIFT);
settings->u1.gain = (uint8_t)((u1value & PGA11X_GAIN_MASK) >> PGA11X_GAIN_SHIFT);
settings->u2.channel = (uint8_t)((u2value & PGA11X_CHAN_MASK) >> PGA11X_CHAN_SHIFT);
settings->u2.gain = (uint8_t)((u2value & PGA11X_GAIN_MASK) >> PGA11X_GAIN_SHIFT);
return OK;
#else
FAR struct spi_dev_s *spi = (FAR struct spi_dev_s *)handle;
uint16_t value;
spivdbg("Entry\n");
DEBUGASSERT(handle);
/* Lock the bus and read the configuration */
pga11x_lock(spi);
/* Select, send the 16-bit PGA11X_CMD_READ command, and de-select. I do
* not know if de-selection between word transfers is required. However,
* it is shown in the timing diagrams for the part.
*/
SPI_SELECT(spi, SPIDEV_MUX, true);
pga11x_send16(spi, PGA11X_CMD_READ);
SPI_SELECT(spi, SPIDEV_MUX, false);
/* Re-select, get the returned value, de-select, and unlock */
SPI_SELECT(spi, SPIDEV_MUX, true);
value = pga11x_recv16(spi);
SPI_SELECT(spi, SPIDEV_MUX, false);
pga11x_unlock(spi);
/* Decode the returned value */
spivdbg("Returning: %04x\n", value);
settings->channel = (uint8_t)((value & PGA11X_CHAN_MASK) >> PGA11X_CHAN_SHIFT);
settings->gain = (uint8_t)((value & PGA11X_GAIN_MASK) >> PGA11X_GAIN_SHIFT);
return OK;
#endif
}
/****************************************************************************
* Name: pga11x_uread
*
* Description:
* Read from one PGA117 amplifier/multiplexer.
*
* If CONFIG_PGA11X_DAISYCHAIN is defined, then pga11x_read() reads
* the parts independently.
*
* Input Parameters:
* spi - An SPI "bottom half" device driver instance
* pos - Position of the chip in the daisy chain (0 or 1)
* settings - Returned channel and gain settings
*
* Returned Value:
* Zero on sucess; a negated errno value on failure.
*
****************************************************************************/
#ifdef CONFIG_PGA11X_DAISYCHAIN
int pga11x_uread(PGA11X_HANDLE handle, int pos,
FAR struct pga11x_usettings_s *settings)
{
struct pga11x_settings_s both;
int ret = pga11x_read(handle, &both);
if (ret == OK)
{
if (pos == 0)
{
settings->channel = both.u1.channel;
settings->gain = both.u1.gain;
}
else /* if (pos == 1) */
{
settings->channel = both.u2.channel;
settings->gain = both.u2.gain;
}
}
return ret;
}
#endif
/****************************************************************************
* Name: pga11x_shutdown
*
* Description:
* Put all PGA11x's in shutdown down mode.
*
* If CONFIG_PGA11X_DAISYCHAIN is defined, then pga11x_shutdown() controls
* both chips in the daisy-chain. pga11x_ushutdown() is provided to
* control the parts independently.
*
* Input Parameters:
* spi - An SPI "bottom half" device driver instance
*
* Returned Value:
* Zero on sucess; a negated errno value on failure.
*
****************************************************************************/
int pga11x_shutdown(PGA11X_HANDLE handle)
{
FAR struct spi_dev_s *spi = (FAR struct spi_dev_s *)handle;
spivdbg("Entry\n");
DEBUGASSERT(handle);
/* Enter shutdown mode by issuing an SDN_EN command */
#ifdef CONFIG_PGA11X_DAISYCHAIN
pga11x_write(spi, PGA11X_CMD_SDN_EN, PGA11X_DCCMD_SDN_EN);
#else
pga11x_write(spi, PGA11X_CMD_SDN_EN);
#endif
return OK;
}
/****************************************************************************
* Name: pga11x_ushutdown
*
* Description:
* Put one PGA11x in shutdown down mode.
*
* If CONFIG_PGA11X_DAISYCHAIN is defined, then pga11x_ushutdown() is
* provided to shutdown the parts independently.
*
* Input Parameters:
* spi - An SPI "bottom half" device driver instance
* pos - Position of the chip in the daisy chain (0 or 1)
*
* Returned Value:
* Zero on sucess; a negated errno value on failure.
*
****************************************************************************/
#ifdef CONFIG_PGA11X_DAISYCHAIN
int pga11x_ushutdown(PGA11X_HANDLE handle, int pos)
{
FAR struct spi_dev_s *spi = (FAR struct spi_dev_s *)handle;
spivdbg("Entry\n");
DEBUGASSERT(handle);
/* Enter shutdown mode by issuing an SDN_EN command */
if (pos == 0)
{
pga11x_write(spi, PGA11X_CMD_SDN_EN, PGA11X_DCCMD_NOOP);
}
else
{
pga11x_write(spi, PGA11X_CMD_NOOP, PGA11X_DCCMD_SDN_EN);
}
return OK;
}
#endif
/****************************************************************************
* Name: pga11x_enable
*
* Description:
* Take all PGA11x's out of shutdown down mode.
*
* If CONFIG_PGA11X_DAISYCHAIN is defined, then pga11x_enable() controls
* both chips in the daisy-chain. pga11x_uenable() is provided to
* control the parts independently.
*
* Input Parameters:
* spi - An SPI "bottom half" device driver instance
*
* Returned Value:
* Zero on sucess; a negated errno value on failure.
*
****************************************************************************/
int pga11x_enable(PGA11X_HANDLE handle)
{
FAR struct spi_dev_s *spi = (FAR struct spi_dev_s *)handle;
spivdbg("Entry\n");
DEBUGASSERT(handle);
/* Lock the bus and send the shutdown disable command. Shutdown mode is
* cleared (returned to the last valid write configuration) by the SDN_DIS
* command or by any valid Write command
*/
#ifdef CONFIG_PGA11X_DAISYCHAIN
pga11x_write(spi, PGA11X_CMD_SDN_DIS, PGA11X_DCCMD_SDN_DIS);
#else
pga11x_write(spi, PGA11X_CMD_SDN_DIS);
#endif
return OK;
}
/****************************************************************************
* Name: pga11x_uenable
*
* Description:
* Take one PGA11x out of shutdown down mode.
*
* If CONFIG_PGA11X_DAISYCHAIN is defined, then pga11x_uenable() is
* provided to enable the parts independently.
*
* Input Parameters:
* spi - An SPI "bottom half" device driver instance
* pos - Position of the chip in the daisy chain (0 or 1)
*
* Returned Value:
* Zero on sucess; a negated errno value on failure.
*
****************************************************************************/
#ifdef CONFIG_PGA11X_DAISYCHAIN
int pga11x_uenable(PGA11X_HANDLE handle, int pos)
{
FAR struct spi_dev_s *spi = (FAR struct spi_dev_s *)handle;
spivdbg("Entry\n");
DEBUGASSERT(handle);
/* Enter shutdown mode by issuing an SDN_EN command */
if (pos == 0)
{
pga11x_write(spi, PGA11X_CMD_SDN_DIS, PGA11X_DCCMD_NOOP);
}
else
{
pga11x_write(spi, PGA11X_CMD_NOOP, PGA11X_DCCMD_SDN_DIS);
}
return OK;
}
#endif
#endif /* CONFIG_ADC && CONFIG_ADC_PGA11X */