/************************************************************************************
* arch/arm/src/stm32/stm32_dac.c
*
* Copyright (C) 2011 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* 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 <stdio.h>
#include <sys/types.h>
#include <stdint.h>
#include <stdbool.h>
#include <semaphore.h>
#include <errno.h>
#include <debug.h>
#include <arch/board/board.h>
#include <nuttx/arch.h>
#include <nuttx/analog/dac.h>
#include "up_internal.h"
#include "up_arch.h"
#include "chip.h"
#include "stm32.h"
#include "stm32_dac.h"
#ifdef CONFIG_DAC
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Configuration ************************************************************/
/* Up to 2 DAC interfaces are supported */
#if STM32_NDAC < 2
# undef CONFIG_STM32_DAC2
# undef CONFIG_STM32_DAC2_DMA
# undef CONFIG_STM32_DAC2_TIMER
# undef CONFIG_STM32_DAC2_TIMER_FREQUENCY
#endif
#if STM32_NDAC < 1
# undef CONFIG_STM32_DAC1
# undef CONFIG_STM32_DAC1_DMA
# undef CONFIG_STM32_DAC1_TIMER
# undef CONFIG_STM32_DAC1_TIMER_FREQUENCY
#endif
#if defined(CONFIG_STM32_DAC1) || defined(CONFIG_STM32_DAC2)
/* DMA configuration. */
#if defined(CONFIG_STM32_DAC1_DMA) || defined(CONFIG_STM32_DAC2_DMA)
# if defined(CONFIG_STM32_STM32F10XX)
# ifndef CONFIG_STM32_DMA2
# warning "STM32 F1 DAC DMA support requires CONFIG_STM32_DMA2"
# undef CONFIG_STM32_DAC1_DMA
# undef CONFIG_STM32_DAC2_DMA
# endif
# elif defined(CONFIG_STM32_STM32F20XX) || defined(CONFIG_STM32_STM32F40XX)
# ifndef CONFIG_STM32_DMA1
# warning "STM32 F4 DAC DMA support requires CONFIG_STM32_DMA1"
# undef CONFIG_STM32_DAC1_DMA
# undef CONFIG_STM32_DAC2_DMA
# endif
# else
# warning "No DAC DMA information for this STM32 family"
# undef CONFIG_STM32_DAC1_DMA
# undef CONFIG_STM32_DAC2_DMA
# endif
#endif
/* If DMA is selected, then a timer and output frequency must also be
* provided to support the DMA transfer. The DMA transfer could be
* supported by and EXTI trigger, but this feature is not currently
* supported by the driver.
*/
#ifdef CONFIG_STM32_DAC1_DMA
# if !defined(CONFIG_STM32_DAC1_TIMER)
# warning "A timer number must be specificed in CONFIG_STM32_DAC1_TIMER"
# undef CONFIG_STM32_DAC1_DMA
# undef CONFIG_STM32_DAC1_TIMER_FREQUENCY
# elif !defined(CONFIG_STM32_DAC1_TIMER_FREQUENCY)
# warning "A timer frequency must be specificed in CONFIG_STM32_DAC1_TIMER_FREQUENCY"
# undef CONFIG_STM32_DAC1_DMA
# undef CONFIG_STM32_DAC1_TIMER
# endif
#endif
#ifdef CONFIG_STM32_DAC2_DMA
# if !defined(CONFIG_STM32_DAC2_TIMER)
# warning "A timer number must be specificed in CONFIG_STM32_DAC2_TIMER"
# undef CONFIG_STM32_DAC2_DMA
# undef CONFIG_STM32_DAC2_TIMER_FREQUENCY
# elif !defined(CONFIG_STM32_DAC2_TIMER_FREQUENCY)
# warning "A timer frequency must be specificed in CONFIG_STM32_DAC2_TIMER_FREQUENCY"
# undef CONFIG_STM32_DAC2_DMA
# undef CONFIG_STM32_DAC2_TIMER
# endif
#endif
/* DMA *********************************************************************/
/* DMA channels and interface values differ for the F1 and F4 families */
#undef HAVE_DMA
#if defined(CONFIG_STM32_DAC1_DMA) || defined(CONFIG_STM32_DAC2_DMA)
# if defined(CONFIG_STM32_STM32F10XX)
# define HAVE_DMA 1
# define DAC_DMA 2
# define DAC1_DMA_CHAN DMACHAN_DAC_CHAN1
# define DAC2_DMA_CHAN DMACHAN_DAC_CHAN2
# elif defined(CONFIG_STM32_STM32F20XX) || defined(CONFIG_STM32_STM32F40XX)
# define HAVE_DMA 1
# define DAC_DMA 1
# define DAC1_DMA_CHAN DMAMAP_DAC1
# define DAC2_DMA_CHAN DMAMAP_DAC2
# endif
#endif
/* Timer configuration. The STM32 supports 8 different trigger for DAC
* output:
*
* TSEL SOURCE DEVICES
* ---- ----------------------- -------------------------------------
* 000 Timer 6 TRGO event ALL
* 001 Timer 3 TRGO event STM32 F1 Connectivity Line
* Timer 8 TRGO event Other STM32 F1 and all STM32 F4
* 010 Timer 7 TRGO event ALL
* 011 Timer 5 TRGO event ALL
* 100 Timer 2 TRGO event ALL
* 101 Timer 4 TRGO event ALL
* 110 EXTI line9 ALL
* 111 SWTRIG Software control ALL
*
* This driver does not support the EXTI trigger.
*/
#ifdef CONFIG_STM32_DAC1_DMA
# if CONFIG_STM32_DAC1_TIMER == 6
# ifndef CONFIG_STM32_TIM6_DAC
# error "CONFIG_STM32_TIM6_DAC required for DAC1"
# endif
# define DAC1_TSEL_VALUE DAC_CR_TSEL_TIM6
# define DAC1_TIMER_BASE STM32_TIM6_BASE
# define DAC1_TIMER_PCLK_FREQUENCY STM32_PCLK1_FREQUENCY
# elif CONFIG_STM32_DAC1_TIMER == 3 && defined(CONFIG_STM32_CONNECTIVITYLINE)
# ifndef CONFIG_STM32_TIM3_DAC
# error "CONFIG_STM32_TIM3_DAC required for DAC1"
# endif
# define DAC1_TSEL_VALUE DAC_CR_TSEL_TIM3
# define DAC1_TIMER_BASE STM32_TIM3_BASE
# define DAC1_TIMER_PCLK_FREQUENCY STM32_PCLK1_FREQUENCY
# elif CONFIG_STM32_DAC1_TIMER == 8 && !defined(CONFIG_STM32_CONNECTIVITYLINE)
# ifndef CONFIG_STM32_TIM8_DAC
# error "CONFIG_STM32_TIM8_DAC required for DAC1"
# endif
# define DAC1_TSEL_VALUE DAC_CR_TSEL_TIM8
# define DAC1_TIMER_BASE STM32_TIM8_BASE
# define DAC1_TIMER_PCLK_FREQUENCY STM32_PCLK2_FREQUENCY
# elif CONFIG_STM32_DAC1_TIMER == 7
# ifndef CONFIG_STM32_TIM7_DAC
# error "CONFIG_STM32_TIM7_DAC required for DAC1"
# endif
# define DAC1_TSEL_VALUE DAC_CR_TSEL_TIM7
# define DAC1_TIMER_BASE STM32_TIM7_BASE
# elif CONFIG_STM32_DAC1_TIMER == 5
# ifndef CONFIG_STM32_TIM5_DAC
# error "CONFIG_STM32_TIM5_DAC required for DAC1"
# endif
# define DAC1_TSEL_VALUE DAC_CR_TSEL_TIM5
# define DAC1_TIMER_BASE STM32_TIM5_BASE
# define DAC1_TIMER_PCLK_FREQUENCY STM32_PCLK1_FREQUENCY
# elif CONFIG_STM32_DAC1_TIMER == 2
# ifndef CONFIG_STM32_TIM2_DAC
# error "CONFIG_STM32_TIM2_DAC required for DAC1"
# endif
# define DAC1_TSEL_VALUE DAC_CR_TSEL_TIM2
# define DAC1_TIMER_BASE STM32_TIM2_BASE
# define DAC1_TIMER_PCLK_FREQUENCY STM32_PCLK1_FREQUENCY
# elif CONFIG_STM32_DAC1_TIMER == 4
# ifndef CONFIG_STM32_TIM4_DAC
# error "CONFIG_STM32_TIM4_DAC required for DAC1"
# endif
# define DAC1_TSEL_VALUE DAC_CR_TSEL_TIM4
# define DAC1_TIMER_BASE STM32_TIM4_BASE
# define DAC1_TIMER_PCLK_FREQUENCY STM32_PCLK1_FREQUENCY
# else
# error "Unsupported CONFIG_STM32_DAC1_TIMER"
# endif
#else
# define DAC1_TSEL_VALUE DAC_CR_TSEL_SW
#endif
#ifdef CONFIG_STM32_DAC2_DMA
# if CONFIG_STM32_DAC2_TIMER == 6
# ifndef CONFIG_STM32_TIM6_DAC
# error "CONFIG_STM32_TIM6_DAC required for DAC2"
# endif
# define DAC2_TSEL_VALUE DAC_CR_TSEL_TIM6
# define DAC2_TIMER_BASE STM32_TIM6_BASE
# define DAC2_TIMER_PCLK_FREQUENCY STM32_PCLK1_FREQUENCY
# elif CONFIG_STM32_DAC2_TIMER == 3 && defined(CONFIG_STM32_CONNECTIVITYLINE)
# ifndef CONFIG_STM32_TIM3_DAC
# error "CONFIG_STM32_TIM3_DAC required for DAC2"
# endif
# define DAC2_TSEL_VALUE DAC_CR_TSEL_TIM3
# define DAC2_TIMER_BASE STM32_TIM3_BASE
# define DAC2_TIMER_PCLK_FREQUENCY STM32_PCLK1_FREQUENCY
# elif CONFIG_STM32_DAC2_TIMER == 8 && !defined(CONFIG_STM32_CONNECTIVITYLINE)
# ifndef CONFIG_STM32_TIM8_DAC
# error "CONFIG_STM32_TIM8_DAC required for DAC2"
# endif
# define DAC2_TSEL_VALUE DAC_CR_TSEL_TIM8
# define DAC2_TIMER_BASE STM32_TIM8_BASE
# define DAC2_TIMER_PCLK_FREQUENCY STM32_PCLK2_FREQUENCY
# elif CONFIG_STM32_DAC2_TIMER == 7
# ifndef CONFIG_STM32_TIM7_DAC
# error "CONFIG_STM32_TIM7_DAC required for DAC2"
# endif
# define DAC2_TSEL_VALUE DAC_CR_TSEL_TIM7
# define DAC2_TIMER_BASE STM32_TIM7_BASE
# define DAC2_TIMER_PCLK_FREQUENCY STM32_PCLK1_FREQUENCY
# elif CONFIG_STM32_DAC2_TIMER == 5
# ifndef CONFIG_STM32_TIM5_DAC
# error "CONFIG_STM32_TIM5_DAC required for DAC2"
# endif
# define DAC2_TSEL_VALUE DAC_CR_TSEL_TIM5
# define DAC2_TIMER_BASE STM32_TIM5_BASE
# define DAC2_TIMER_PCLK_FREQUENCY STM32_PCLK1_FREQUENCY
# elif CONFIG_STM32_DAC2_TIMER == 2
# ifndef CONFIG_STM32_TIM2_DAC
# error "CONFIG_STM32_TIM2_DAC required for DAC2"
# endif
# define DAC2_TSEL_VALUE DAC_CR_TSEL_TIM2
# define DAC2_TIMER_BASE STM32_TIM2_BASE
# define DAC2_TIMER_PCLK_FREQUENCY STM32_PCLK1_FREQUENCY
# elif CONFIG_STM32_DAC2_TIMER == 4
# ifndef CONFIG_STM32_TIM4_DAC
# error "CONFIG_STM32_TIM4_DAC required for DAC2"
# endif
# define DAC2_TSEL_VALUE DAC_CR_TSEL_TIM4
# define DAC2_TIMER_BASE STM32_TIM4_BASE
# define DAC2_TIMER_PCLK_FREQUENCY STM32_PCLK1_FREQUENCY
# else
# error "Unsupported CONFIG_STM32_DAC2_TIMER"
# endif
#else
# define DAC2_TSEL_VALUE DAC_CR_TSEL_SW
#endif
/* Calculate timer divider values based upon DACn_TIMER_PCLK_FREQUENCY and
* CONFIG_STM32_DACn_TIMER_FREQUENCY.
*/
#warning "Missing Logic"
/****************************************************************************
* Private Types
****************************************************************************/
/* This structure represents the internal state of the single STM32 DAC block */
struct stm32_dac_s
{
uint8_t init : 1; /* True, the DAC block has been initialized */
};
/* This structure represents the internal state of one STM32 DAC channel */
struct stm32_chan_s
{
uint8_t inuse : 1; /* True, the driver is in use and not available */
#ifdef HAVE_DMA
uint8_t hasdma : 1; /* True, this channel supports DMA */
#endif
uint8_t intf; /* DAC zero-based interface number (0 or 1) */
#ifdef HAVE_DMA
uint16_t dmachan; /* DMA channel needed by this DAC */
DMA_HANDLE dma; /* Allocated DMA channel */
uint32_t tsel; /* CR trigger select value */
uint32_t tbase; /* Timer base address */
#endif
};
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
/* DAC Register access */
#ifdef HAVE_DMA
static uint32_t tim_getreg(struct stm32_chan_s *chan, int offset);
static void tim_putreg(struct stm32_chan_s *chan, int offset, uint32_t value);
#endif
/* Interrupt handler */
#if defined(CONFIG_STM32_STM32F20XX) || defined(CONFIG_STM32_STM32F40XX)
static int dac_interrupt(int irq, void *context);
#endif
/* DAC methods */
static void dac_reset(FAR struct dac_dev_s *dev);
static int dac_setup(FAR struct dac_dev_s *dev);
static void dac_shutdown(FAR struct dac_dev_s *dev);
static void dac_txint(FAR struct dac_dev_s *dev, bool enable);
static int dac_send(FAR struct dac_dev_s *dev, FAR struct dac_msg_s *msg);
static int dac_ioctl(FAR struct dac_dev_s *dev, int cmd, unsigned long arg);
static int dac_interrupt(int irq, void *context);
/* Initialization */
#ifdef HAVE_DMA
static int dac_timinit(struct stm32_chan_s *chan);
#endif
static int dac_chaninit(struct stm32_chan_s *chan);
static int dac_blockinit(void);
/****************************************************************************
* Private Data
****************************************************************************/
static const struct dac_ops_s g_dacops =
{
.ao_reset = dac_reset,
.ao_setup = dac_setup,
.ao_shutdown = dac_shutdown,
.ao_txint = dac_txint,
.ao_send = dac_send,
.ao_ioctl = dac_ioctl,
};
#ifdef CONFIG_STM32_DAC1
static struct stm32_chan_s g_dac1priv =
{
.intf = 0;
#ifdef CONFIG_STM32_DAC1_DMA
.hasdma = 1;
.dmachan = DAC1_DMA_CHAN,
.tsel = DAC1_TSEL_VALUE,
.tbase = DAC1_TIMER_BASE
#endif
}
static struct dac_dev_s g_dac1dev =
{
.ad_ops = &g_dacops,
.ad_priv = &g_dac1priv,
};
#endif
#ifdef CONFIG_STM32_DAC2
static struct stm32_chan_s g_dac2priv =
{
.intf = 1;
#ifdef CONFIG_STM32_DAC2_DMA
.hasdma = 1;
.dmachan = DAC2_DMA_CHAN,
.tsel = DAC2_TSEL_VALUE.
.tbase = DAC2_TIMER_BASE
#endif
}
static struct dac_dev_s g_dac2dev =
{
.ad_ops = &g_dacops,
.ad_priv = &g_dac2priv,
};
#endif
static struct stm32_dac_s g_dacblock;
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: tim_getreg
*
* Description:
* Read the value of an DMA timer register.
*
* Input Parameters:
* chan - A reference to the DAC block status
* offset - The offset to the register to read
*
* Returned Value:
* The current contents of the specified register
*
****************************************************************************/
#ifdef HAVE_DMA
static uint32_t tim_getreg(struct stm32_chan_s *chan, int offset)
{
return getreg32(chan->tbase + offset);
}
#endif
/****************************************************************************
* Name: tim_putreg
*
* Description:
* Read the value of an DMA timer register.
*
* Input Parameters:
* chan - A reference to the DAC block status
* offset - The offset to the register to read
*
* Returned Value:
* None
*
****************************************************************************/
static void tim_putreg(struct stm32_chan_s *chan, int offset, uint32_t value)
{
putreg32(value, chan->tbase + offset);
}
#endif
/****************************************************************************
* Name: dac_interrupt
*
* Description:
* DAC interrupt handler. The STM32 F4 family supports a only a DAC
* underrun interrupt.
*
* Input Parameters:
*
* Returned Value:
* OK
*
****************************************************************************/
#if defined(CONFIG_STM32_STM32F20XX) || defined(CONFIG_STM32_STM32F40XX)
static int dac_interrupt(int irq, void *context)
{
#warning "Missing logic"
return OK;
}
#endif
/****************************************************************************
* Name: dac_reset
*
* Description:
* Reset the DAC channel. Called early to initialize the hardware. This
* is called, before dac_setup() and on error conditions.
*
* NOTE: DAC reset will reset both DAC channels!
*
* Input Parameters:
*
* Returned Value:
* None
*
****************************************************************************/
static void dac_reset(FAR struct dac_dev_s *dev)
{
irqstate_t flags;
uint32_t regval;
/* Reset only the selected DAC channel; the other DAC channel must remain
* functional.
*/
flags = irqsave();
#warning "Missing logic"
irqrestore(flags);
}
/****************************************************************************
* Name: dac_setup
*
* Description:
* Configure the DAC. This method is called the first time that the DAC
* device is opened. This will occur when the port is first opened.
* This setup includes configuring and attaching DAC interrupts. Interrupts
* are all disabled upon return.
*
* Input Parameters:
*
* Returned Value:
* Zero on success; a negated errno value on failure.
*
****************************************************************************/
static int dac_setup(FAR struct dac_dev_s *dev)
{
# warning "Missing logic"
return -ENOSYS;
}
/****************************************************************************
* Name: dac_shutdown
*
* Description:
* Disable the DAC. This method is called when the DAC device is closed.
* This method reverses the operation the setup method.
*
* Input Parameters:
*
* Returned Value:
* None
*
****************************************************************************/
static void dac_shutdown(FAR struct dac_dev_s *dev)
{
# warning "Missing logic"
}
/****************************************************************************
* Name: dac_txint
*
* Description:
* Call to enable or disable TX interrupts.
*
* Input Parameters:
*
* Returned Value:
* None
*
****************************************************************************/
static void dac_txint(FAR struct dac_dev_s *dev, bool enable)
{
# warning "Missing logic"
}
/****************************************************************************
* Name: dac_send
*
* Description:
* Set the DAC output.
*
* Input Parameters:
*
* Returned Value:
* Zero on success; a negated errno value on failure.
*
****************************************************************************/
static int dac_send(FAR struct dac_dev_s *dev, FAR struct dac_msg_s *msg)
{
#ifdef HAVE_DMA
if (priv->hasdma)
{
/* Configure the DMA stream/channel.
*
* - Channel number
* - Peripheral address
* - Direction: Memory to peripheral
* - Disable peripheral address increment
* - Enable memory address increment
* - Peripheral data size: half word
* - Mode: circular???
* - Priority: ?
* - FIFO mode: disable
* - FIFO threshold: half full
* - Memory Burst: single
* - Peripheral Burst: single
*/
#warning "Missing logic"
/* Enable DMA */
#warning "Missing logic"
/* Enable DAC Channel */
#warning "Missing logic"
/* Enable DMA for DAC Channel */
#warning "Missing logic"
}
else
{
/* Non-DMA transfer */
#warning "Missing logic"
}
return -ENOSYS;
}
/****************************************************************************
* Name: dac_ioctl
*
* Description:
* All ioctl calls will be routed through this method.
*
* Input Parameters:
*
* Returned Value:
* Zero on success; a negated errno value on failure.
*
****************************************************************************/
static int dac_ioctl(FAR struct dac_dev_s *dev, int cmd, unsigned long arg)
{
return -ENOTTY;
}
/****************************************************************************
* Name: dac_timinit
*
* Description:
* Initialize the timer that drivers the DAC DMA for this channel using
* the pre-calculated timer divider definitions.
*
* Input Parameters:
* chan - A reference to the DAC channel state data
*
* Returned Value:
* Zero on success; a negated errno value on failure.
*
****************************************************************************/
#ifdef HAVE_DMA
static int dac_timinit(struct stm32_chan_s *chan)
{
/* Configure the time base: Timer period, prescaler, clock division,
* counter mode (up).
*/
#warning "Missing Logic"
/* Selection TRGO selection: update */
#warning "Missing Logic"
/* Enable the counter */
#warning "Missing Logic"
}
#endif
/****************************************************************************
* Name: dac_chaninit
*
* Description:
* Initialize the DAC channel.
*
* Input Parameters:
* chan - A reference to the DAC channel state data
*
* Returned Value:
* Zero on success; a negated errno value on failure.
*
****************************************************************************/
static int dac_chaninit(struct stm32_chan_s *chan)
{
/* Is the selected channel already in-use? */
if (chan->inuse)
{
/* Yes.. then return EBUSY */
return -EBUSY;
}
/* Configure the DAC output pin:
*
* DAC -" Once the DAC channelx is enabled, the corresponding GPIO pin
* (PA4 or PA5) is automatically connected to the analog converter output
* (DAC_OUTx). In order to avoid parasitic consumption, the PA4 or PA5 pin
* should first be configured to analog (AIN)".
*/
stm32_configgpio(chan->intf ? GPIO_DAC2_OUT : GPIO_DAC1_OUT);
/* DAC channel configuration:
*
* - Set the trigger selection based upon the configuration.
* - Set wave generation == None.
* - Enable the output buffer.
*/
#warning "Missing logic"
/* Determine if DMA is supported by this channel */
#ifdef HAVE_DMA
if (priv->hasdma)
{
/* Yes.. allocate a DMA channel */
priv->dma = stm32_dmachannel(priv->dmachan);
if (!priv->dma)
{
adbg("Failed to allocate a DMA channel\n");
return -EBUSY;
}
/* Configure the timer that supports the DMA operation */
ret = dac_timinit(chan);
if (ret < 0)
{
adbg("Failed to initialize the DMA timer: %d\n", ret);
return ret;
}
}
#endif
/* Mark the DAC channel "in-use" */
chan->inuse = 1;
return OK;
}
/****************************************************************************
* Name: dac_blockinit
*
* Description:
* All ioctl calls will be routed through this method.
*
* Input Parameters:
*
* Returned Value:
* Zero on success; a negated errno value on failure.
*
****************************************************************************/
static int dac_blockinit(void)
{
irqstate_t flags;
uint32_t regval;
/* Has the DMA block already been initialized? */
if (g_dacblock.init)
{
/* Yes.. then return success We only have to do this once */
return OK;
}
/* Put the entire DAC block in reset state */
flags = irqsave();
regval = getreg32(STM32_RCC_APB1RSTR);
regval |= RCC_APB1RSTR_DACRST
putreg32(regval, STM32_RCC_APB1RSTR);
/* Take the DAC out of reset state */
regval &= ~RCC_APB1RSTR_DACRST
putreg32(regval, STM32_RCC_APB1RSTR);
irqrestore(flags);
/* Mark the DAC block as initialized */
g_dacblock.init = 1;
return OK;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: stm32_dacinitialize
*
* Description:
* Initialize the DAC.
*
* Input Parameters:
* intf - The DAC interface number.
*
* Returned Value:
* Valid dac device structure reference on succcess; a NULL on failure.
*
* Assumptions:
* 1. Clock to the DAC block has enabled,
* 2. Board-specific logic has already configured
*
****************************************************************************/
FAR struct dac_dev_s *stm32_dacinitialize(int intf)
{
FAR struct dac_dev_s *dev;
FAR struct stm32_chan_s *chan;
int ret;
#ifdef CONFIG_STM32_DAC1
if (intf == 1)
{
avdbg("DAC1 Selected\n");
dev = &g_dacdev1;
}
else
#endif
#ifdef CONFIG_STM32_DAC2
if (intf == 2)
{
avdbg("DAC2 Selected\n");
dev = &g_dac2dev;
}
else
#endif
{
adbg("No such DAC interface: %d\n", intf);
return NULL;
}
/* Make sure that the DAC block has been initialized */
ret = dac_blockinit();
if (ret < 0)
{
adbg("Failed to initialize the DAC block: %d\n", ret);
return ret;
}
/* Configure the selected DAC channel */
chan = dev->ad_priv;
ret = dac_chaninit(chan);
if (ret < 0)
{
adbg("Failed to initialize DAC channel %d: %d\n", intf, ret);
return ret;
}
return dev;
}
#endif /* CONFIG_STM32_DAC1 || CONFIG_STM32_DAC2 */
#endif /* CONFIG_DAC */
