/* * Copyright (C) 2016 Inria * * This file is subject to the terms and conditions of the GNU Lesser * General Public License v2.1. See the file LICENSE in the top level * directory for more details. */ /** * @ingroup drivers_tsl2561 * @{ * * @file * @brief Device driver implementation for the TSL2561 Luminosity sensor. * * @author Alexandre Abadie * * @} */ #include #include #include "log.h" #include "tsl2561.h" #include "tsl2561_internals.h" #include "periph/i2c.h" #include "ztimer.h" #define ENABLE_DEBUG 0 #include "debug.h" #define DEV_I2C (dev->params.i2c_dev) #define DEV_ADDR (dev->params.addr) #define DEV_GAIN (dev->params.gain) #define DEV_INTEGRATION (dev->params.integration) /* internal helpers */ static void _enable(const tsl2561_t *dev); static void _disable(const tsl2561_t *dev); static void _read_data(const tsl2561_t *dev, uint16_t *full, uint16_t *ir); static void _print_init_info(const tsl2561_t *dev); /*---------------------------------------------------------------------------* * TSL2561 Core API * *---------------------------------------------------------------------------*/ int tsl2561_init(tsl2561_t *dev, const tsl2561_params_t *params) { dev->params = *params; _print_init_info(dev); DEBUG("[Info] I2C device initialized with success!\n"); /* Acquire exclusive access */ i2c_acquire(DEV_I2C); DEBUG("[Info] Access acquired !\n"); /* Verify sensor ID */ uint8_t id; i2c_read_reg(DEV_I2C, DEV_ADDR, TSL2561_COMMAND_MODE | TSL2561_REGISTER_ID, &id, 0); DEBUG("[Info] ID ? %d\n", id); if (id != TSL2561_ID ) { DEBUG("[Error] not a TSL2561 sensor\n"); return TSL2561_BADDEV; } _enable(dev); /* configuring gain and integration time */ i2c_write_reg(DEV_I2C, DEV_ADDR, TSL2561_COMMAND_MODE | TSL2561_REGISTER_TIMING, DEV_INTEGRATION | DEV_GAIN, 0); if (IS_ACTIVE(ENABLE_DEBUG)) { uint8_t timing; i2c_read_reg(DEV_I2C, DEV_ADDR, TSL2561_COMMAND_MODE | TSL2561_REGISTER_TIMING, &timing, 0); DEBUG("[Info] Timing ? %d (expected: %d)\n", timing, DEV_INTEGRATION | DEV_GAIN); } _disable(dev); i2c_release(DEV_I2C); return TSL2561_OK; } uint16_t tsl2561_read_illuminance(const tsl2561_t *dev) { /* Read IR and full spectrum values */ uint16_t ir = 0; uint16_t full = 0; _read_data(dev, &full, &ir); DEBUG("[Info] Full spectrum value: %i\n", (int)full); DEBUG("[Info] IR spectrum value: %i\n", (int)ir); /* Compute illuminance */ uint32_t channel_scale; uint32_t channel_1; uint32_t channel_0; switch (DEV_INTEGRATION) { case TSL2561_INTEGRATIONTIME_13MS: channel_scale = TSL2561_CHSCALE_TINT0; break; case TSL2561_INTEGRATIONTIME_101MS: channel_scale = TSL2561_CHSCALE_TINT1; break; default: /* No scaling ... integration time = 402ms */ channel_scale = (1 << TSL2561_CHSCALE); break; } /* Scale for gain (1x or 16x) */ if (!DEV_GAIN) { channel_scale = channel_scale << 4; } /* scale the channel values */ channel_0 = (full * channel_scale) >> TSL2561_CHSCALE; channel_1 = (ir * channel_scale) >> TSL2561_CHSCALE; /* find the ratio of the channel values (Channel1/Channel0) */ uint32_t ratio_1 = 0; if (channel_0 != 0) { ratio_1 = (channel_1 << (TSL2561_RATIOSCALE + 1)) / channel_0; } /* round the ratio value */ uint32_t ratio = (ratio_1 + 1) >> 1; uint32_t b, m; if (ratio <= TSL2561_K1T) { b = TSL2561_B1T; m = TSL2561_M1T; } else if (ratio <= TSL2561_K2T) { b = TSL2561_B2T; m = TSL2561_M2T; } else if (ratio <= TSL2561_K3T) { b = TSL2561_B3T; m = TSL2561_M3T; } else if (ratio <= TSL2561_K4T) { b = TSL2561_B4T; m = TSL2561_M4T; } else if (ratio <= TSL2561_K5T) { b = TSL2561_B5T; m = TSL2561_M5T; } else if (ratio <= TSL2561_K6T) { b = TSL2561_B6T; m = TSL2561_M6T; } else if (ratio <= TSL2561_K7T) { b = TSL2561_B7T; m = TSL2561_M7T; } else { b = TSL2561_B8T; m = TSL2561_M8T; } uint32_t illuminance; illuminance = ((channel_0 * b) - (channel_1 * m)); /* round lsb (2^(TSL2561_SCALE - 1)) */ illuminance += (1 << (TSL2561_LUXSCALE - 1)); /* return strip off fractional portion */ return (uint16_t)(illuminance >> TSL2561_LUXSCALE); } static void _enable(const tsl2561_t *dev) { /* enabling device */ i2c_write_reg(DEV_I2C, DEV_ADDR, TSL2561_COMMAND_MODE | TSL2561_REGISTER_CONTROL, TSL2561_CONTROL_POWERON, 0); if (IS_ACTIVE(ENABLE_DEBUG)) { uint8_t en; i2c_read_reg(DEV_I2C, DEV_ADDR, TSL2561_COMMAND_MODE | TSL2561_REGISTER_CONTROL, &en, 0); DEBUG("[Info] Enabled ? %s\n", en == 3 ? "true" : "false"); } } static void _disable(const tsl2561_t *dev) { /* disabling device */ i2c_write_reg(DEV_I2C, DEV_ADDR, TSL2561_COMMAND_MODE | TSL2561_REGISTER_CONTROL, TSL2561_CONTROL_POWEROFF, 0); if (IS_ACTIVE(ENABLE_DEBUG)) { uint8_t dis; i2c_read_reg(DEV_I2C, DEV_ADDR, TSL2561_COMMAND_MODE | TSL2561_REGISTER_CONTROL, &dis, 0); DEBUG("[Info] Disabled ? %s\n", dis == 0 ? "true": "false"); } } static void _read_data(const tsl2561_t *dev, uint16_t *full, uint16_t *ir) { /* acquire bus */ i2c_acquire(DEV_I2C); /* Enable the device */ _enable(dev); /* Wait integration time in ms for ADC to complete */ switch (DEV_INTEGRATION) { case TSL2561_INTEGRATIONTIME_13MS: /* 13700us */ ztimer_sleep(ZTIMER_MSEC, 14); break; case TSL2561_INTEGRATIONTIME_101MS: ztimer_sleep(ZTIMER_MSEC, 101); break; default: /* TSL2561_INTEGRATIONTIME_402MS */ ztimer_sleep(ZTIMER_MSEC, 402); break; } char buffer[2] = { 0 }; /* Read full spectrum channel */ i2c_read_regs(DEV_I2C, DEV_ADDR, TSL2561_COMMAND_MODE | TSL2561_COMMAND_WORD | TSL2561_REGISTER_CHAN0, buffer, 2, 0); *full = (buffer[1] << 8) | buffer[0]; memset(buffer, 0, sizeof(buffer)); /* Read infrared spectrum channel */ i2c_read_regs(DEV_I2C, DEV_ADDR, TSL2561_COMMAND_MODE | TSL2561_COMMAND_WORD | TSL2561_REGISTER_CHAN1, buffer, 2, 0); *ir = (buffer[1] << 8) | buffer[0]; /* Turn the device off to save power */ _disable(dev); /* release bus */ i2c_release(DEV_I2C); } static void _print_init_info(const tsl2561_t *dev) { DEBUG("[Info] I2C device: %d\n", DEV_I2C); DEBUG("[Info] Address: %d\n", DEV_ADDR); switch(DEV_GAIN) { case TSL2561_GAIN_1X: DEBUG("[Info] Gain: 1X\n"); break; case TSL2561_GAIN_16X: DEBUG("[Info] Gain: 16X\n"); break; default: DEBUG("[Info] Invalid gain %d\n", DEV_GAIN); break; } switch(DEV_INTEGRATION) { case TSL2561_INTEGRATIONTIME_13MS: DEBUG("[Info] Integration time: 13ms\n"); break; case TSL2561_INTEGRATIONTIME_101MS: DEBUG("[Info] Integration time: 101ms\n"); break; case TSL2561_INTEGRATIONTIME_402MS: DEBUG("[Info] Integration time: 402ms\n"); break; case TSL2561_INTEGRATIONTIME_NA: DEBUG("[Info] Integration time: n/a\n"); break; default: DEBUG("[Info] Invalid integration time %d\n", DEV_INTEGRATION); break; } }