diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/Makefile | 2 | ||||
| -rw-r--r-- | src/sensor_adxl345.c | 179 |
2 files changed, 180 insertions, 1 deletions
diff --git a/src/Makefile b/src/Makefile index 92be64e2..98c9a1c1 100644 --- a/src/Makefile +++ b/src/Makefile @@ -7,4 +7,4 @@ src-$(CONFIG_HAVE_GPIO_SPI) += spicmds.c thermocouple.c src-$(CONFIG_HAVE_GPIO_I2C) += i2ccmds.c src-$(CONFIG_HAVE_GPIO_HARD_PWM) += pwmcmds.c src-$(CONFIG_HAVE_GPIO_BITBANGING) += lcd_st7920.c lcd_hd44780.c buttons.c \ - tmcuart.c spi_software.c neopixel.c + tmcuart.c spi_software.c neopixel.c sensor_adxl345.c diff --git a/src/sensor_adxl345.c b/src/sensor_adxl345.c new file mode 100644 index 00000000..c76ab7db --- /dev/null +++ b/src/sensor_adxl345.c @@ -0,0 +1,179 @@ +// Support for gathering acceleration data from ADXL345 chip +// +// Copyright (C) 2020 Kevin O'Connor <kevin@koconnor.net> +// +// This file may be distributed under the terms of the GNU GPLv3 license. + +#include <string.h> // memcpy +#include "board/irq.h" // irq_disable +#include "board/misc.h" // timer_read_time +#include "basecmd.h" // oid_alloc +#include "command.h" // DECL_COMMAND +#include "sched.h" // DECL_TASK +#include "spicmds.h" // spidev_transfer + +struct adxl345 { + struct timer timer; + uint32_t rest_ticks, stop_time; + struct spidev_s *spi; + uint16_t sequence, limit_count; + uint8_t flags, data_count; + uint8_t data[48]; +}; + +enum { + AX_HAVE_START = 1<<0, AX_RUNNING = 1<<1, AX_PENDING = 1<<2, +}; + +static struct task_wake adxl345_wake; + +static uint_fast8_t +adxl345_event(struct timer *timer) +{ + struct adxl345 *ax = container_of(timer, struct adxl345, timer); + ax->flags |= AX_PENDING; + sched_wake_task(&adxl345_wake); + return SF_DONE; +} + +void +command_config_adxl345(uint32_t *args) +{ + struct adxl345 *ax = oid_alloc(args[0], command_config_adxl345 + , sizeof(*ax)); + ax->timer.func = adxl345_event; + ax->spi = spidev_oid_lookup(args[1]); +} +DECL_COMMAND(command_config_adxl345, "config_adxl345 oid=%c spi_oid=%c"); + +// Report local measurement buffer +static void +adxl_report(struct adxl345 *ax, uint8_t oid) +{ + sendf("adxl345_data oid=%c sequence=%hu data=%*s" + , oid, ax->sequence, ax->data_count, ax->data); + ax->data_count = 0; + ax->sequence++; +} + +// Chip registers +#define AR_POWER_CTL 0x2D +#define AR_DATAX0 0x32 +#define AR_FIFO_STATUS 0x39 +#define AM_READ 0x80 +#define AM_MULTI 0x40 + +// Query accelerometer data +static void +adxl_query(struct adxl345 *ax, uint8_t oid) +{ + uint8_t msg[9] = { AR_DATAX0 | AM_READ | AM_MULTI, 0, 0, 0, 0, 0, 0, 0, 0 }; + spidev_transfer(ax->spi, 1, sizeof(msg), msg); + memcpy(&ax->data[ax->data_count], &msg[1], 6); + ax->data_count += 6; + if (ax->data_count + 6 > ARRAY_SIZE(ax->data)) + adxl_report(ax, oid); + uint_fast8_t fifo_status = msg[8] & ~0x80; // Ignore trigger bit + if (fifo_status >= 31 && ax->limit_count != 0xffff) + ax->limit_count++; + if (fifo_status > 1 && fifo_status <= 32) { + // More data in fifo - wake this task again + sched_wake_task(&adxl345_wake); + } else if (ax->flags & AX_RUNNING) { + // Sleep until next check time + sched_del_timer(&ax->timer); + ax->flags &= ~AX_PENDING; + irq_disable(); + ax->timer.waketime = timer_read_time() + ax->rest_ticks; + sched_add_timer(&ax->timer); + irq_enable(); + } +} + +// Startup measurements +static void +adxl_start(struct adxl345 *ax, uint8_t oid) +{ + sched_del_timer(&ax->timer); + ax->flags = AX_RUNNING; + uint8_t msg[2] = { AR_POWER_CTL, 0x08 }; + uint32_t start1_time = timer_read_time(); + spidev_transfer(ax->spi, 0, sizeof(msg), msg); + irq_disable(); + uint32_t start2_time = timer_read_time(); + ax->timer.waketime = start2_time + ax->rest_ticks; + sched_add_timer(&ax->timer); + irq_enable(); + sendf("adxl345_start oid=%c start1_time=%u start2_time=%u" + , oid, start1_time, start2_time); +} + +// End measurements +static void +adxl_stop(struct adxl345 *ax, uint8_t oid) +{ + // Disable measurements + sched_del_timer(&ax->timer); + ax->flags = 0; + uint8_t msg[2] = { AR_POWER_CTL, 0x00 }; + uint32_t end1_time = timer_read_time(); + spidev_transfer(ax->spi, 0, sizeof(msg), msg); + uint32_t end2_time = timer_read_time(); + // Drain any measurements still in fifo + uint_fast8_t i; + for (i=0; i<33; i++) { + msg[0] = AR_FIFO_STATUS | AM_READ; + msg[1] = 0; + spidev_transfer(ax->spi, 1, sizeof(msg), msg); + if (!(msg[1] & 0x3f)) + break; + adxl_query(ax, oid); + } + // Report final data + if (ax->data_count) + adxl_report(ax, oid); + sendf("adxl345_end oid=%c end1_time=%u end2_time=%u" + " limit_count=%hu sequence=%hu" + , oid, end1_time, end2_time, ax->limit_count, ax->sequence); +} + +void +command_query_adxl345(uint32_t *args) +{ + struct adxl345 *ax = oid_lookup(args[0], command_config_adxl345); + + if (!args[2]) { + // End measurements + adxl_stop(ax, args[0]); + return; + } + // Start new measurements query + sched_del_timer(&ax->timer); + ax->timer.waketime = args[1]; + ax->rest_ticks = args[2]; + ax->flags = AX_HAVE_START; + ax->sequence = ax->limit_count = 0; + ax->data_count = 0; + sched_add_timer(&ax->timer); +} +DECL_COMMAND(command_query_adxl345, + "query_adxl345 oid=%c clock=%u rest_ticks=%u"); + +void +adxl345_task(void) +{ + if (!sched_check_wake(&adxl345_wake)) + return; + uint8_t oid; + struct adxl345 *ax; + foreach_oid(oid, ax, command_config_adxl345) { + uint_fast8_t flags = ax->flags; + if (!(flags & AX_PENDING)) + continue; + if (flags & AX_HAVE_START) + adxl_start(ax, oid); + else + adxl_query(ax, oid); + } +} +DECL_TASK(adxl345_task); |