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author | Lorenz Meier <lm@inf.ethz.ch> | 2013-04-28 01:17:12 +0200 |
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committer | Lorenz Meier <lm@inf.ethz.ch> | 2013-04-28 01:30:14 +0200 |
commit | f57439b90e23de260259dec051d3e2ead2d61c8c (patch) | |
tree | 5cd778d2cf0c9afb2851ab9042bbecc5b742a497 /src/drivers/stm32/adc/adc.cpp | |
parent | 8040b9b96e8f7c07aa981150c33f850096062f70 (diff) | |
download | px4-firmware-f57439b90e23de260259dec051d3e2ead2d61c8c.tar.gz px4-firmware-f57439b90e23de260259dec051d3e2ead2d61c8c.tar.bz2 px4-firmware-f57439b90e23de260259dec051d3e2ead2d61c8c.zip |
Moved all drivers to new world, PX4IO completely in new world
Diffstat (limited to 'src/drivers/stm32/adc/adc.cpp')
-rw-r--r-- | src/drivers/stm32/adc/adc.cpp | 387 |
1 files changed, 387 insertions, 0 deletions
diff --git a/src/drivers/stm32/adc/adc.cpp b/src/drivers/stm32/adc/adc.cpp new file mode 100644 index 000000000..911def943 --- /dev/null +++ b/src/drivers/stm32/adc/adc.cpp @@ -0,0 +1,387 @@ +/**************************************************************************** + * + * Copyright (C) 2012 PX4 Development Team. All rights reserved. + * + * 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 PX4 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. + * + ****************************************************************************/ + +/** + * @file adc.cpp + * + * Driver for the STM32 ADC. + * + * This is a low-rate driver, designed for sampling things like voltages + * and so forth. It avoids the gross complexity of the NuttX ADC driver. + */ + +#include <nuttx/config.h> +#include <drivers/device/device.h> + +#include <sys/types.h> +#include <stdint.h> +#include <stdbool.h> +#include <stdlib.h> +#include <string.h> +#include <fcntl.h> +#include <errno.h> +#include <stdio.h> +#include <unistd.h> + +#include <arch/board/board.h> +#include <drivers/drv_hrt.h> +#include <drivers/drv_adc.h> + +#include <arch/stm32/chip.h> +#include <stm32_internal.h> +#include <stm32_gpio.h> + +#include <systemlib/err.h> +#include <systemlib/perf_counter.h> + +/* + * Register accessors. + * For now, no reason not to just use ADC1. + */ +#define REG(_reg) (*(volatile uint32_t *)(STM32_ADC1_BASE + _reg)) + +#define rSR REG(STM32_ADC_SR_OFFSET) +#define rCR1 REG(STM32_ADC_CR1_OFFSET) +#define rCR2 REG(STM32_ADC_CR2_OFFSET) +#define rSMPR1 REG(STM32_ADC_SMPR1_OFFSET) +#define rSMPR2 REG(STM32_ADC_SMPR2_OFFSET) +#define rJOFR1 REG(STM32_ADC_JOFR1_OFFSET) +#define rJOFR2 REG(STM32_ADC_JOFR2_OFFSET) +#define rJOFR3 REG(STM32_ADC_JOFR3_OFFSET) +#define rJOFR4 REG(STM32_ADC_JOFR4_OFFSET) +#define rHTR REG(STM32_ADC_HTR_OFFSET) +#define rLTR REG(STM32_ADC_LTR_OFFSET) +#define rSQR1 REG(STM32_ADC_SQR1_OFFSET) +#define rSQR2 REG(STM32_ADC_SQR2_OFFSET) +#define rSQR3 REG(STM32_ADC_SQR3_OFFSET) +#define rJSQR REG(STM32_ADC_JSQR_OFFSET) +#define rJDR1 REG(STM32_ADC_JDR1_OFFSET) +#define rJDR2 REG(STM32_ADC_JDR2_OFFSET) +#define rJDR3 REG(STM32_ADC_JDR3_OFFSET) +#define rJDR4 REG(STM32_ADC_JDR4_OFFSET) +#define rDR REG(STM32_ADC_DR_OFFSET) + +#ifdef STM32_ADC_CCR +# define rCCR REG(STM32_ADC_CCR_OFFSET) +#endif + +class ADC : public device::CDev +{ +public: + ADC(uint32_t channels); + ~ADC(); + + virtual int init(); + + virtual int ioctl(file *filp, int cmd, unsigned long arg); + virtual ssize_t read(file *filp, char *buffer, size_t len); + +protected: + virtual int open_first(struct file *filp); + virtual int close_last(struct file *filp); + +private: + static const hrt_abstime _tickrate = 10000; /**< 100Hz base rate */ + + hrt_call _call; + perf_counter_t _sample_perf; + + unsigned _channel_count; + adc_msg_s *_samples; /**< sample buffer */ + + /** work trampoline */ + static void _tick_trampoline(void *arg); + + /** worker function */ + void _tick(); + + /** + * Sample a single channel and return the measured value. + * + * @param channel The channel to sample. + * @return The sampled value, or 0xffff if + * sampling failed. + */ + uint16_t _sample(unsigned channel); + +}; + +ADC::ADC(uint32_t channels) : + CDev("adc", ADC_DEVICE_PATH), + _sample_perf(perf_alloc(PC_ELAPSED, "ADC samples")), + _channel_count(0), + _samples(nullptr) +{ + _debug_enabled = true; + + /* always enable the temperature sensor */ + channels |= 1 << 16; + + /* allocate the sample array */ + for (unsigned i = 0; i < 32; i++) { + if (channels & (1 << i)) { + _channel_count++; + } + } + _samples = new adc_msg_s[_channel_count]; + + /* prefill the channel numbers in the sample array */ + if (_samples != nullptr) { + unsigned index = 0; + for (unsigned i = 0; i < 32; i++) { + if (channels & (1 << i)) { + _samples[index].am_channel = i; + _samples[index].am_data = 0; + index++; + } + } + } +} + +ADC::~ADC() +{ + if (_samples != nullptr) + delete _samples; +} + +int +ADC::init() +{ + /* do calibration if supported */ +#ifdef ADC_CR2_CAL + rCR2 |= ADC_CR2_CAL; + usleep(100); + if (rCR2 & ADC_CR2_CAL) + return -1; +#endif + + /* arbitrarily configure all channels for 55 cycle sample time */ + rSMPR1 = 0b00000011011011011011011011011011; + rSMPR2 = 0b00011011011011011011011011011011; + + /* XXX for F2/4, might want to select 12-bit mode? */ + rCR1 = 0; + + /* enable the temperature sensor / Vrefint channel if supported*/ + rCR2 = +#ifdef ADC_CR2_TSVREFE + /* enable the temperature sensor in CR2 */ + ADC_CR2_TSVREFE | +#endif + 0; + +#ifdef ADC_CCR_TSVREFE + /* enable temperature sensor in CCR */ + rCCR = ADC_CCR_TSVREFE; +#endif + + /* configure for a single-channel sequence */ + rSQR1 = 0; + rSQR2 = 0; + rSQR3 = 0; /* will be updated with the channel each tick */ + + /* power-cycle the ADC and turn it on */ + rCR2 &= ~ADC_CR2_ADON; + usleep(10); + rCR2 |= ADC_CR2_ADON; + usleep(10); + rCR2 |= ADC_CR2_ADON; + usleep(10); + + /* kick off a sample and wait for it to complete */ + hrt_abstime now = hrt_absolute_time(); + rCR2 |= ADC_CR2_SWSTART; + while (!(rSR & ADC_SR_EOC)) { + + /* don't wait for more than 500us, since that means something broke - should reset here if we see this */ + if ((hrt_absolute_time() - now) > 500) { + log("sample timeout"); + return -1; + return 0xffff; + } + } + + + debug("init done"); + + /* create the device node */ + return CDev::init(); +} + +int +ADC::ioctl(file *filp, int cmd, unsigned long arg) +{ + return -ENOTTY; +} + +ssize_t +ADC::read(file *filp, char *buffer, size_t len) +{ + const size_t maxsize = sizeof(adc_msg_s) * _channel_count; + + if (len > maxsize) + len = maxsize; + + /* block interrupts while copying samples to avoid racing with an update */ + irqstate_t flags = irqsave(); + memcpy(buffer, _samples, len); + irqrestore(flags); + + return len; +} + +int +ADC::open_first(struct file *filp) +{ + /* get fresh data */ + _tick(); + + /* and schedule regular updates */ + hrt_call_every(&_call, _tickrate, _tickrate, _tick_trampoline, this); + + return 0; +} + +int +ADC::close_last(struct file *filp) +{ + hrt_cancel(&_call); + return 0; +} + +void +ADC::_tick_trampoline(void *arg) +{ + ((ADC *)arg)->_tick(); +} + +void +ADC::_tick() +{ + /* scan the channel set and sample each */ + for (unsigned i = 0; i < _channel_count; i++) + _samples[i].am_data = _sample(_samples[i].am_channel); +} + +uint16_t +ADC::_sample(unsigned channel) +{ + perf_begin(_sample_perf); + + /* clear any previous EOC */ + if (rSR & ADC_SR_EOC) + rSR &= ~ADC_SR_EOC; + + /* run a single conversion right now - should take about 60 cycles (a few microseconds) max */ + rSQR3 = channel; + rCR2 |= ADC_CR2_SWSTART; + + /* wait for the conversion to complete */ + hrt_abstime now = hrt_absolute_time(); + while (!(rSR & ADC_SR_EOC)) { + + /* don't wait for more than 50us, since that means something broke - should reset here if we see this */ + if ((hrt_absolute_time() - now) > 50) { + log("sample timeout"); + return 0xffff; + } + } + + /* read the result and clear EOC */ + uint16_t result = rDR; + + perf_end(_sample_perf); + return result; +} + +/* + * Driver 'main' command. + */ +extern "C" __EXPORT int adc_main(int argc, char *argv[]); + +namespace +{ +ADC *g_adc; + +void +test(void) +{ + + int fd = open(ADC_DEVICE_PATH, O_RDONLY); + if (fd < 0) + err(1, "can't open ADC device"); + + for (unsigned i = 0; i < 50; i++) { + adc_msg_s data[8]; + ssize_t count = read(fd, data, sizeof(data)); + + if (count < 0) + errx(1, "read error"); + + unsigned channels = count / sizeof(data[0]); + + for (unsigned j = 0; j < channels; j++) { + printf ("%d: %u ", data[j].am_channel, data[j].am_data); + } + + printf("\n"); + usleep(500000); + } + + exit(0); +} +} + +int +adc_main(int argc, char *argv[]) +{ + if (g_adc == nullptr) { + /* XXX this hardcodes the default channel set for PX4FMU - should be configurable */ + g_adc = new ADC((1 << 10) | (1 << 11) | (1 << 12) | (1 << 13)); + + if (g_adc == nullptr) + errx(1, "couldn't allocate the ADC driver"); + + if (g_adc->init() != OK) { + delete g_adc; + errx(1, "ADC init failed"); + } + } + + if (argc > 1) { + if (!strcmp(argv[1], "test")) + test(); + } + + exit(0); +} |