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Diff: targets/hal/TARGET_Atmel/TARGET_SAM_CortexM0P/drivers/TARGET_SAMD21/dac/dac_sam_d_c/dac.c
- Revision:
- 15:a81a8d6c1dfe
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/targets/hal/TARGET_Atmel/TARGET_SAM_CortexM0P/drivers/TARGET_SAMD21/dac/dac_sam_d_c/dac.c Wed Nov 04 16:30:11 2015 +0000 @@ -0,0 +1,774 @@ +/** + * \file + * + * \brief SAM Peripheral Digital-to-Analog Converter Driver + * + * Copyright (C) 2012-2015 Atmel Corporation. All rights reserved. + * + * \asf_license_start + * + * \page License + * + * 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. The name of Atmel may not be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * 4. This software may only be redistributed and used in connection with an + * Atmel microcontroller product. + * + * THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR IMPLIED + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE + * EXPRESSLY AND SPECIFICALLY DISCLAIMED. IN NO EVENT SHALL ATMEL 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. + * + * \asf_license_stop + * + */ +/* + * Support and FAQ: visit <a href="http://www.atmel.com/design-support/">Atmel Support</a> + */ +#include "dac.h" +#include <system.h> +#include <pinmux.h> + +/** + * \internal Writes a DAC configuration to the hardware module. + * + * Writes out a given configuration to the hardware module. + * + * \param[out] module_inst Pointer to the DAC software instance struct + * \param[in] config Pointer to the configuration struct + * + */ +static void _dac_set_config( + struct dac_module *const module_inst, + struct dac_config *const config) +{ + /* Sanity check arguments */ + Assert(module_inst); + Assert(config); + Assert(module_inst->hw); + + Dac *const dac_module = module_inst->hw; + + /* Set selected DAC output to be enabled when enabling the module */ + module_inst->output = config->output; + module_inst->start_on_event = false; + + uint32_t new_ctrla = 0; + uint32_t new_ctrlb = 0; + + /* Enable DAC in standby sleep mode if configured */ + if (config->run_in_standby) { + new_ctrla |= DAC_CTRLA_RUNSTDBY; + } + + /* Set reference voltage */ + new_ctrlb |= config->reference; + + /* Left adjust data if configured */ + if (config->left_adjust) { + new_ctrlb |= DAC_CTRLB_LEFTADJ; + } + +#ifdef FEATURE_DAC_DATABUF_WRITE_PROTECTION + /* Bypass DATABUF write protection if configured */ + if (config->databuf_protection_bypass) { + new_ctrlb |= DAC_CTRLB_BDWP; + } +#endif + + /* Voltage pump disable if configured */ + if (config->voltage_pump_disable) { + new_ctrlb |= DAC_CTRLB_VPD; + } + + /* Apply the new configuration to the hardware module */ + dac_module->CTRLA.reg = new_ctrla; + + while (dac_is_syncing(module_inst)) { + /* Wait until the synchronization is complete */ + } + + dac_module->CTRLB.reg = new_ctrlb; +} + +/** + * \brief Determines if the hardware module(s) are currently synchronizing to the bus. + * + * Checks to see if the underlying hardware peripheral module(s) are currently + * synchronizing across multiple clock domains to the hardware bus, This + * function can be used to delay further operations on a module until such time + * that it is ready, to prevent blocking delays for synchronization in the + * user application. + * + * \param[in] dev_inst Pointer to the DAC software instance struct + * + * \return Synchronization status of the underlying hardware module(s). + * + * \retval true If the module synchronization is ongoing + * \retval false If the module has completed synchronization + */ +bool dac_is_syncing( + struct dac_module *const dev_inst) +{ + /* Sanity check arguments */ + Assert(dev_inst); + + Dac *const dac_module = dev_inst->hw; + +#if (SAMC21) + if (dac_module->SYNCBUSY.reg) { +#else + if (dac_module->STATUS.reg & DAC_STATUS_SYNCBUSY) { +#endif + return true; + } + + return false; +} + +/** + * \brief Initializes a DAC configuration structure to defaults. + * + * Initializes a given DAC configuration structure to a set of + * known default values. This function should be called on any new + * instance of the configuration structures before being modified by the + * user application. + * + * The default configuration is as follows: + * \li 1V from internal bandgap reference + * \li Drive the DAC output to the VOUT pin + * \li Right adjust data + * \li GCLK generator 0 (GCLK main) clock source + * \li The output buffer is disabled when the chip enters STANDBY sleep + * mode + * + * \param[out] config Configuration structure to initialize to default values + */ +void dac_get_config_defaults( + struct dac_config *const config) +{ + /* Sanity check arguments */ + Assert(config); + + /* Default configuration values */ + config->reference = DAC_REFERENCE_INT1V; + config->output = DAC_OUTPUT_EXTERNAL; + config->left_adjust = false; +#ifdef FEATURE_DAC_DATABUF_WRITE_PROTECTION + config->databuf_protection_bypass = false; +#endif + config->voltage_pump_disable = false; + config->clock_source = GCLK_GENERATOR_0; + config->run_in_standby = false; +#if (SAMC21) + config->dither_mode = false; +#endif +} + +/** + * \brief Initialize the DAC device struct. + * + * Use this function to initialize the Digital to Analog Converter. Resets the + * underlying hardware module and configures it. + * + * \note The DAC channel must be configured separately. + * + * \param[out] module_inst Pointer to the DAC software instance struct + * \param[in] module Pointer to the DAC module instance + * \param[in] config Pointer to the config struct, created by the user + * application + * + * \return Status of initialization. + * \retval STATUS_OK Module initiated correctly + * \retval STATUS_ERR_DENIED If module is enabled + * \retval STATUS_BUSY If module is busy resetting + */ +enum status_code dac_init( + struct dac_module *const module_inst, + Dac *const module, + struct dac_config *const config) +{ + /* Sanity check arguments */ + Assert(module_inst); + Assert(module); + Assert(config); + + /* Initialize device instance */ + module_inst->hw = module; + + /* Turn on the digital interface clock */ +#if (SAMC21) + system_apb_clock_set_mask(SYSTEM_CLOCK_APB_APBC, MCLK_APBCMASK_DAC); +#else + system_apb_clock_set_mask(SYSTEM_CLOCK_APB_APBC, PM_APBCMASK_DAC); +#endif + + /* Check if module is enabled. */ + if (module->CTRLA.reg & DAC_CTRLA_ENABLE) { + return STATUS_ERR_DENIED; + } + + /* Check if reset is in progress. */ + if (module->CTRLA.reg & DAC_CTRLA_SWRST) { + return STATUS_BUSY; + } + + /* Configure GCLK channel and enable clock */ + struct system_gclk_chan_config gclk_chan_conf; + system_gclk_chan_get_config_defaults(&gclk_chan_conf); + gclk_chan_conf.source_generator = config->clock_source; + system_gclk_chan_set_config(DAC_GCLK_ID, &gclk_chan_conf); + system_gclk_chan_enable(DAC_GCLK_ID); + + /* MUX the DAC VOUT pin */ + struct system_pinmux_config pin_conf; + system_pinmux_get_config_defaults(&pin_conf); + + /* Set up the DAC VOUT pin */ + pin_conf.mux_position = MUX_PA02B_DAC_VOUT; + pin_conf.direction = SYSTEM_PINMUX_PIN_DIR_INPUT; + pin_conf.input_pull = SYSTEM_PINMUX_PIN_PULL_NONE; + system_pinmux_pin_set_config(PIN_PA02B_DAC_VOUT, &pin_conf); + + /* Write configuration to module */ + _dac_set_config(module_inst, config); + + /* Store reference selection for later use */ + module_inst->reference = config->reference; + +#if DAC_CALLBACK_MODE == true + for (uint8_t i = 0; i < DAC_CALLBACK_N; i++) { + module_inst->callback[i] = NULL; + }; + + _dac_instances[0] = module_inst; +#endif + + return STATUS_OK; +} + +/** + * \brief Resets the DAC module. + * + * This function will reset the DAC module to its power on default values and + * disable it. + * + * \param[in] module_inst Pointer to the DAC software instance struct + */ +void dac_reset( + struct dac_module *const module_inst) +{ + /* Sanity check arguments */ + Assert(module_inst); + Assert(module_inst->hw); + + Dac *const dac_module = module_inst->hw; + + while (dac_is_syncing(module_inst)) { + /* Wait until the synchronization is complete */ + } + + /* Software reset the module */ + dac_module->CTRLA.reg |= DAC_CTRLA_SWRST; +} + +/** + * \brief Enable the DAC module. + * + * Enables the DAC interface and the selected output. If any internal reference + * is selected it will be enabled. + * + * \param[in] module_inst Pointer to the DAC software instance struct + * + */ +void dac_enable( + struct dac_module *const module_inst) +{ + /* Sanity check arguments */ + Assert(module_inst); + Assert(module_inst->hw); + + Dac *const dac_module = module_inst->hw; + + /* Enable selected output */ + dac_module->CTRLB.reg |= module_inst->output; + + while (dac_is_syncing(module_inst)) { + /* Wait until the synchronization is complete */ + } + + /* Enable the module */ + dac_module->CTRLA.reg |= DAC_CTRLA_ENABLE; + + /* Enable internal bandgap reference if selected in the configuration */ + if (module_inst->reference == DAC_REFERENCE_INT1V) { +#if (SAMC21) + system_voltage_reference_enable(SYSTEM_VOLTAGE_REFERENCE_OUTPUT); + } + + if(dac_module->CTRLA.reg & DAC_CTRLA_ENABLE) { + while(! (dac_module->STATUS.reg & DAC_STATUS_READY)) { + }; + } +#else + system_voltage_reference_enable(SYSTEM_VOLTAGE_REFERENCE_BANDGAP); + } + +#endif +} + +/** + * \brief Disable the DAC module. + * + * Disables the DAC interface and the output buffer. + * + * \param[in] module_inst Pointer to the DAC software instance struct + * + */ +void dac_disable( + struct dac_module *const module_inst) +{ + /* Sanity check arguments */ + Assert(module_inst); + Assert(module_inst->hw); + + Dac *const dac_module = module_inst->hw; + + /* Wait until the synchronization is complete */ + while (dac_is_syncing(module_inst)) { + }; + + /* Disable DAC */ + dac_module->CTRLA.reg &= ~DAC_CTRLA_ENABLE; +} + +/** + * \brief Enables a DAC event input or output. + * + * Enables one or more input or output events to or from the DAC module. See + * \ref dac_events "here" for a list of events this module supports. + * + * \note Events cannot be altered while the module is enabled. + * + * \param[in] module_inst Software instance for the DAC peripheral + * \param[in] events Struct containing flags of events to enable + */ +void dac_enable_events( + struct dac_module *const module_inst, + struct dac_events *const events) +{ + /* Sanity check arguments */ + Assert(module_inst); + Assert(module_inst->hw); + Assert(events); + + Dac *const dac_module = module_inst->hw; + + uint32_t event_mask = 0; + +#if(SAMC21) + /* Configure Enable Inversion of input event */ + if (events->generate_event_on_chan_falling_edge) { + event_mask |= DAC_EVCTRL_INVEI; + } +#endif + + /* Configure Buffer Empty event */ + if (events->generate_event_on_buffer_empty) { + event_mask |= DAC_EVCTRL_EMPTYEO; + } + + /* Configure Conversion Start event */ + if (events->on_event_start_conversion) { + event_mask |= DAC_EVCTRL_STARTEI; + module_inst->start_on_event = true; + } + + dac_module->EVCTRL.reg |= event_mask; +} + +/** + * \brief Disables a DAC event input or output. + * + * Disables one or more input or output events to or from the DAC module. See + * \ref dac_events "here" for a list of events this module supports. + * + * \note Events cannot be altered while the module is enabled. + * + * \param[in] module_inst Software instance for the DAC peripheral + * \param[in] events Struct containing flags of events to disable + */ +void dac_disable_events( + struct dac_module *const module_inst, + struct dac_events *const events) +{ + /* Sanity check arguments */ + Assert(module_inst); + Assert(module_inst->hw); + Assert(events); + + Dac *const dac_module = module_inst->hw; + + uint32_t event_mask = 0; + + /* Configure Buffer Empty event */ + if (events->generate_event_on_buffer_empty) { + event_mask |= DAC_EVCTRL_EMPTYEO; + } + + /* Configure Conversion Start event */ + if (events->on_event_start_conversion) { + event_mask |= DAC_EVCTRL_STARTEI; + module_inst->start_on_event = false; + } + + dac_module->EVCTRL.reg &= ~event_mask; +} + +/** + * \brief Initializes a DAC channel configuration structure to defaults. + * + * Initializes a given DAC channel configuration structure to a set of + * known default values. This function should be called on any new + * instance of the configuration structures before being modified by the + * user application. + * + * The default configuration is as follows: + * \li Start Conversion Event Input enabled + * \li Start Data Buffer Empty Event Output disabled + * + * \param[out] config Configuration structure to initialize to default values + */ +void dac_chan_get_config_defaults( + struct dac_chan_config *const config) +{ + /* Sanity check arguments */ + Assert(config); +} + +/** + * \brief Writes a DAC channel configuration to the hardware module. + * + * Writes a given channel configuration to the hardware module. + * + * \note The DAC device instance structure must be initialized before calling + * this function. + * + * \param[in] module_inst Pointer to the DAC software instance struct + * \param[in] channel Channel to configure + * \param[in] config Pointer to the configuration struct + * + */ +void dac_chan_set_config( + struct dac_module *const module_inst, + const enum dac_channel channel, + struct dac_chan_config *const config) +{ + /* No channel support yet */ + UNUSED(channel); +} + +/** + * \brief Enable a DAC channel. + * + * Enables the selected DAC channel. + * + * \param[in] module_inst Pointer to the DAC software instance struct + * \param[in] channel Channel to enable + * + */ +void dac_chan_enable( + struct dac_module *const module_inst, + enum dac_channel channel) +{ + /* No channel support yet */ + UNUSED(channel); +} + +/** + * \brief Disable a DAC channel. + * + * Disables the selected DAC channel. + * + * \param[in] module_inst Pointer to the DAC software instance struct + * \param[in] channel Channel to disable + * + */ +void dac_chan_disable( + struct dac_module *const module_inst, + enum dac_channel channel) +{ + /* No channel support yet */ + UNUSED(channel); +} + +/** + * \brief Enable the output buffer. + * + * Enables the output buffer and drives the DAC output to the VOUT pin. + * + * \param[in] module_inst Pointer to the DAC software instance struct + * \param[in] channel DAC channel to alter + */ +void dac_chan_enable_output_buffer( + struct dac_module *const module_inst, + enum dac_channel channel) +{ + /* Sanity check arguments */ + Assert(module_inst); + Assert(module_inst->hw); + + /* No channel support yet */ + UNUSED(channel); + + Dac *const dac_module = module_inst->hw; + + /* Enable output buffer */ + dac_module->CTRLB.reg |= DAC_OUTPUT_EXTERNAL; +} + +/** + * \brief Disable the output buffer. + * + * Disables the output buffer. + * + * \note The output buffer(s) should be disabled when a channel's output is not + * currently needed, as it will draw current even if the system is in + * sleep mode. + * + * \param[in] module_inst Pointer to the DAC software instance struct + * \param[in] channel DAC channel to alter + */ +void dac_chan_disable_output_buffer( + struct dac_module *const module_inst, + enum dac_channel channel) +{ + /* Sanity check arguments*/ + Assert(module_inst); + Assert(module_inst->hw); + + /* No channel support yet */ + UNUSED(channel); + + Dac *const dac_module = module_inst->hw; + + /* Disable output buffer */ + dac_module->CTRLB.reg &= ~DAC_OUTPUT_EXTERNAL; +} + +/** + * \brief Write to the DAC. + * + * This function writes to the DATA or DATABUF register. + * If the conversion is not event-triggered, the data will be written to + * the DATA register and the conversion will start. + * If the conversion is event-triggered, the data will be written to DATABUF + * and transferred to the DATA register and converted when a Start Conversion + * Event is issued. + * Conversion data must be right or left adjusted according to configuration + * settings. + * \note To be event triggered, the enable_start_on_event must be + * enabled in the configuration. + * + * \param[in] module_inst Pointer to the DAC software device struct + * \param[in] channel DAC channel to write to + * \param[in] data Conversion data + * + * \return Status of the operation. + * \retval STATUS_OK If the data was written + */ +enum status_code dac_chan_write( + struct dac_module *const module_inst, + enum dac_channel channel, + const uint16_t data) +{ + /* Sanity check arguments */ + Assert(module_inst); + Assert(module_inst->hw); + + /* No channel support yet */ + UNUSED(channel); + + Dac *const dac_module = module_inst->hw; + + /* Wait until the synchronization is complete */ + while (dac_is_syncing(module_inst)) { + }; + + if (module_inst->start_on_event) { + /* Write the new value to the buffered DAC data register */ + dac_module->DATABUF.reg = data; + } else { + /* Write the new value to the DAC data register */ + dac_module->DATA.reg = data; + } + + return STATUS_OK; +} + +/** + * \brief Write to the DAC. + * + * This function converts a specific number of digital data. + * The conversion should be event-triggered, the data will be written to DATABUF + * and transferred to the DATA register and converted when a Start Conversion + * Event is issued. + * Conversion data must be right or left adjusted according to configuration + * settings. + * \note To be event triggered, the enable_start_on_event must be + * enabled in the configuration. + * + * \param[in] module_inst Pointer to the DAC software device struct + * \param[in] channel DAC channel to write to + * \param[in] buffer Pointer to the digital data write buffer to be converted + * \param[in] length Length of the write buffer + * + * \return Status of the operation. + * \retval STATUS_OK If the data was written or no data conversion required + * \retval STATUS_ERR_UNSUPPORTED_DEV The DAC is not configured as using event trigger + * \retval STATUS_BUSY The DAC is busy to convert + */ +enum status_code dac_chan_write_buffer_wait( + struct dac_module *const module_inst, + enum dac_channel channel, + uint16_t *buffer, + uint32_t length) +{ + /* Sanity check arguments */ + Assert(module_inst); + Assert(module_inst->hw); + + /* No channel support yet */ + UNUSED(channel); + + Dac *const dac_module = module_inst->hw; + + /* Wait until the synchronization is complete */ + while (dac_is_syncing(module_inst)) { + }; + + /* Zero length request */ + if (length == 0) { + /* No data to be converted */ + return STATUS_OK; + } + +#if DAC_CALLBACK_MODE == true + /* Check if busy */ + if (module_inst->job_status == STATUS_BUSY) { + return STATUS_BUSY; + } +#endif + + /* Only support event triggered conversion */ + if (module_inst->start_on_event == false) { + return STATUS_ERR_UNSUPPORTED_DEV; + } + + /* Blocks while buffer is being transferred */ + while (length--) { + /* Convert one data */ + dac_chan_write(module_inst, channel, buffer[length]); + + /* Wait until Transmit is complete or timeout */ + for (uint32_t i = 0; i <= DAC_TIMEOUT; i++) { + if (dac_module->INTFLAG.reg & DAC_INTFLAG_EMPTY) { + break; + } else if (i == DAC_TIMEOUT) { + return STATUS_ERR_TIMEOUT; + } + } + } + + return STATUS_OK; +} + +/** + * \brief Retrieves the current module status + * + * Checks the status of the module and returns it as a bitmask of status + * flags. + * + * \param[in] module_inst Pointer to the DAC software device struct + * + * \return Bitmask of status flags. + * + * \retval DAC_STATUS_CHANNEL_0_EMPTY Data has been transferred from DATABUF + * to DATA by a start conversion event + * and DATABUF is ready for new data + * \retval DAC_STATUS_CHANNEL_0_UNDERRUN A start conversion event has occurred + * when DATABUF is empty + * + */ +uint32_t dac_get_status( + struct dac_module *const module_inst) +{ + /* Sanity check arguments */ + Assert(module_inst); + Assert(module_inst->hw); + + Dac *const dac_module = module_inst->hw; + + uint8_t intflags = dac_module->INTFLAG.reg; + uint32_t status_flags = 0; + + if (intflags & DAC_INTFLAG_EMPTY) { + status_flags |= DAC_STATUS_CHANNEL_0_EMPTY; + } + + if (intflags & DAC_INTFLAG_UNDERRUN) { + status_flags |= DAC_STATUS_CHANNEL_0_UNDERRUN; + } + + return status_flags; +} + +/** + * \brief Clears a module status flag + * + * Clears the given status flag of the module. + * + * \param[in] module_inst Pointer to the DAC software device struct + * \param[in] status_flags Bit mask of status flags to clear + * + */ +void dac_clear_status( + struct dac_module *const module_inst, + uint32_t status_flags) +{ + /* Sanity check arguments */ + Assert(module_inst); + Assert(module_inst->hw); + + Dac *const dac_module = module_inst->hw; + + uint32_t intflags = 0; + + if (status_flags & DAC_STATUS_CHANNEL_0_EMPTY) { + intflags |= DAC_INTFLAG_EMPTY; + } + + if (status_flags & DAC_STATUS_CHANNEL_0_UNDERRUN) { + intflags |= DAC_INTFLAG_UNDERRUN; + } + + dac_module->INTFLAG.reg = intflags; +}