/**************************************************************************** * drivers/sensors/as5048b.c * Character driver for the AMS AS5048B Magnetic Rotary Encoder * * Copyright (C) 2015 Omni Hoverboards Inc. All rights reserved. * Author: Paul Alexander Patience * * Copyright (C) 2016 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * 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 #include #include #include #include #include #include #include #if defined(CONFIG_I2C) && defined(CONFIG_QENCODER) && defined(CONFIG_AS5048B) /**************************************************************************** * Private Types ****************************************************************************/ struct as5048b_dev_s { struct qe_lowerhalf_s lower; /* AS5048B quadrature encoder lower half */ FAR struct i2c_master_s *i2c; /* I2C interface */ uint8_t addr; /* I2C address */ }; /**************************************************************************** * Private Function Prototypes ****************************************************************************/ /* I2C Helpers */ static int as5048b_readu8(FAR struct as5048b_dev_s *priv, uint8_t regaddr, FAR uint8_t *regval); static int as5048b_readu16(FAR struct as5048b_dev_s *priv, uint8_t regaddrhi, uint8_t regaddrlo, FAR uint16_t *regval); static int as5048b_writeu8(FAR struct as5048b_dev_s *priv, uint8_t regaddr, uint8_t regval); static int as5048b_writeu16(FAR struct as5048b_dev_s *priv, uint8_t regaddrhi, uint8_t regaddrlo, uint16_t regval); static int as5048b_readzero(FAR struct as5048b_dev_s *priv, FAR uint16_t *zero); static int as5048b_writezero(FAR struct as5048b_dev_s *priv, uint16_t zero); static int as5048b_readagc(FAR struct as5048b_dev_s *priv, FAR uint8_t *agc); static int as5048b_readdiag(FAR struct as5048b_dev_s *priv, FAR uint8_t *diag); static int as5048b_readmag(FAR struct as5048b_dev_s *priv, FAR uint16_t *mag); static int as5048b_readang(FAR struct as5048b_dev_s *priv, FAR uint16_t *ang); /* Character Driver Methods */ static int as5048b_setup(FAR struct qe_lowerhalf_s *lower); static int as5048b_shutdown(FAR struct qe_lowerhalf_s *lower); static int as5048b_position(FAR struct qe_lowerhalf_s *lower, FAR int32_t *pos); static int as5048b_reset(FAR struct qe_lowerhalf_s *lower); static int as5048b_ioctl(FAR struct qe_lowerhalf_s *lower, int cmd, unsigned long arg); /**************************************************************************** * Private Data ****************************************************************************/ static const struct qe_ops_s g_qeops = { as5048b_setup, as5048b_shutdown, as5048b_position, as5048b_reset, as5048b_ioctl }; /**************************************************************************** * Private Functions ****************************************************************************/ /**************************************************************************** * Name: as5048b_readu8 * * Description: * Read from an 8-bit register * ****************************************************************************/ static int as5048b_readu8(FAR struct as5048b_dev_s *priv, uint8_t regaddr, FAR uint8_t *regval) { int ret; struct i2c_config_s config; /* Set up the I2C configuration */ config.frequency = priv->frequency; config.address = priv->addr; config.addrlen = 7; /* Write the register address */ ret = i2c_write(priv->i2c, &config, ®addr, sizeof(regaddr)); if (ret < 0) { sndbg("i2c_write failed: %d\n", ret); return ret; } /* Restart and read 8 bits from the register */ ret = i2c_read(priv->i2c, &config, regval, sizeof(*regval)); if (ret < 0) { sndbg("i2c_read failed: %d\n", ret); return ret; } sndbg("addr: %02x value: %02x ret: %d\n", regaddr, *regval, ret); return ret; } /**************************************************************************** * Name: as5048b_readu16 * * Description: * Read from two 8-bit registers * ****************************************************************************/ static int as5048b_readu16(FAR struct as5048b_dev_s *priv, uint8_t regaddrhi, uint8_t regaddrlo, FAR uint16_t *regval) { uint8_t hi, lo; int ret; /* Read the high 8 bits of the 13-bit value */ ret = as5048b_readu8(priv, regaddrhi, &hi); if (ret < 0) { sndbg("as5048b_readu8 failed: %d\n", ret); return ret; } /* Read the low 5 bits of the 13-bit value */ ret = as5048b_readu8(priv, regaddrlo, &lo); if (ret < 0) { sndbg("as5048b_readu8 failed: %d\n", ret); return ret; } *regval = (uint16_t)hi << 6 | (uint16_t)lo; sndbg("addrhi: %02x addrlo: %02x value: %04x ret: %d\n", regaddrhi, regaddrlo, *regval, ret); return ret; } /**************************************************************************** * Name: as5048b_writeu8 * * Description: * Write from an 8-bit register * ****************************************************************************/ static int as5048b_writeu8(FAR struct as5048b_dev_s *priv, uint8_t regaddr, uint8_t regval) { struct i2c_config_s config; uint8_t buffer[2]; int ret; sndbg("addr: %02x value: %02x\n", regaddr, regval); /* Set up the I2C configuration */ config.frequency = priv->frequency; config.address = priv->addr; config.addrlen = 7; /* Set up a 2-byte message to send */ buffer[0] = regaddr; buffer[1] = regval; /* Write the register address followed by the data (no RESTART) */ ret = i2c_write(priv->i2c, &config, buffer, sizeof(buffer)); if (ret < 0) { sndbg("i2c_write failed: %d\n", ret); } return ret; } /**************************************************************************** * Name: as5048b_writeu16 * * Description: * Write to two 8-bit registers * ****************************************************************************/ static int as5048b_writeu16(FAR struct as5048b_dev_s *priv, uint8_t regaddrhi, uint8_t regaddrlo, uint16_t regval) { int ret; sndbg("addrhi: %02x addrlo: %02x value: %04x\n", regaddrhi, regaddrlo, regval); /* Write the high 8 bits of the 13-bit value */ ret = as5048b_writeu8(priv, regaddrhi, (uint8_t)(regval >> 6)); if (ret < 0) { sndbg("as5048b_writeu8 failed: %d\n", ret); return ret; } /* Write the low 5 bits of the 13-bit value */ ret = as5048b_writeu8(priv, regaddrhi, (uint8_t)regval); if (ret < 0) { sndbg("as5048b_writeu8 failed: %d\n", ret); } return ret; } /**************************************************************************** * Name: as5048b_readzero * * Description: * Read from the zero position registers * ****************************************************************************/ static int as5048b_readzero(FAR struct as5048b_dev_s *priv, FAR uint16_t *zero) { int ret; ret = as5048b_readu16(priv, AS5048B_ZEROHI_REG, AS5048B_ZEROLO_REG, zero); if (ret < 0) { sndbg("as5048b_readu16 failed: %d\n", ret); return ret; } sndbg("zero: %04x ret: %d\n", *zero, ret); return ret; } /**************************************************************************** * Name: as5048b_writezero * * Description: * Write to the zero position registers * ****************************************************************************/ static int as5048b_writezero(FAR struct as5048b_dev_s *priv, uint16_t zero) { int ret; sndbg("zero: %04x\n", zero); ret = as5048b_writeu16(priv, AS5048B_ZEROHI_REG, AS5048B_ZEROLO_REG, zero); if (ret < 0) { sndbg("as5048b_writeu16 failed: %d\n", ret); } return ret; } /**************************************************************************** * Name: as5048b_readagc * * Description: * Read from the automatic gain control register * ****************************************************************************/ static int as5048b_readagc(FAR struct as5048b_dev_s *priv, FAR uint8_t *agc) { int ret; ret = as5048b_readu8(priv, AS5048B_AGC_REG, agc); if (ret < 0) { sndbg("as5048b_readu8 failed: %d\n", ret); return ret; } sndbg("agc: %02x ret: %d\n", *agc, ret); return ret; } /**************************************************************************** * Name: as5048b_readdiag * * Description: * Read from the diagnostics register * ****************************************************************************/ static int as5048b_readdiag(FAR struct as5048b_dev_s *priv, FAR uint8_t *diag) { int ret; ret = as5048b_readu8(priv, AS5048B_DIAG_REG, diag); if (ret < 0) { sndbg("as5048b_readu8 failed: %d\n", ret); return ret; } sndbg("diag: %02x ret: %d\n", *diag, ret); return ret; } /**************************************************************************** * Name: as5048b_readmag * * Description: * Read from the magnitude registers * ****************************************************************************/ static int as5048b_readmag(FAR struct as5048b_dev_s *priv, FAR uint16_t *mag) { int ret; ret = as5048b_readu16(priv, AS5048B_MAGHI_REG, AS5048B_MAGLO_REG, mag); if (ret < 0) { sndbg("as5048b_readu16 failed: %d\n", ret); return ret; } sndbg("mag: %04x ret: %d\n", *mag, ret); return ret; } /**************************************************************************** * Name: as5048b_readang * * Description: * Read from the angle registers * ****************************************************************************/ static int as5048b_readang(FAR struct as5048b_dev_s *priv, FAR uint16_t *ang) { int ret; ret = as5048b_readu16(priv, AS5048B_ANGHI_REG, AS5048B_ANGLO_REG, ang); if (ret < 0) { sndbg("as5048b_readu16 failed: %d\n", ret); return ret; } sndbg("ang: %04x ret: %d\n", *ang, ret); return ret; } /**************************************************************************** * Name: as5048b_setup * * Description: * This method is called when the driver is opened * ****************************************************************************/ static int as5048b_setup(FAR struct qe_lowerhalf_s *lower) { return OK; } /**************************************************************************** * Name: as5048b_shutdown * * Description: * This method is called when the driver is closed * ****************************************************************************/ static int as5048b_shutdown(FAR struct qe_lowerhalf_s *lower) { return OK; } /**************************************************************************** * Name: as5048b_position * * Description: * Return the current position measurement * ****************************************************************************/ static int as5048b_position(FAR struct qe_lowerhalf_s *lower, FAR int32_t *pos) { FAR struct as5048b_dev_s *priv = (FAR struct as5048b_dev_s *)lower; uint16_t ang; int ret; ret = as5048b_readang(priv, &ang); if (ret < 0) { sndbg("as5048b_readang failed: %d\n", ret); return ret; } *pos = (int32_t)ang; return ret; } /**************************************************************************** * Name: as5048b_reset * * Description: * Reset the position measurement to zero * ****************************************************************************/ static int as5048b_reset(FAR struct qe_lowerhalf_s *lower) { FAR struct as5048b_dev_s *priv = (FAR struct as5048b_dev_s *)lower; uint16_t ang; int ret; ret = as5048b_writezero(priv, 0); if (ret < 0) { sndbg("as5048b_writezero failed: %d\n", ret); return ret; } ret = as5048b_readang(priv, &ang); if (ret < 0) { sndbg("as5048b_readang failed: %d\n", ret); return ret; } ret = as5048b_writezero(priv, ang); if (ret < 0) { sndbg("as5048b_writezero failed: %d\n", ret); } return ret; } /**************************************************************************** * Name: as5048b_ioctl ****************************************************************************/ static int as5048b_ioctl(FAR struct qe_lowerhalf_s *lower, int cmd, unsigned long arg) { FAR struct as5048b_dev_s *priv = (FAR struct as5048b_dev_s *)lower; int ret = OK; switch (cmd) { /* Read from the zero position registers. Arg: int32_t* pointer. */ case QEIOC_ZEROPOSITION: { FAR int32_t *ptr = (FAR int32_t *)((uintptr_t)arg); uint16_t zero; DEBUGASSERT(ptr != NULL); ret = as5048b_readzero(priv, &zero); if (ret == OK) { *ptr = (int32_t)zero; } sndbg("zero: %04x ret: %d\n", *ptr, ret); } break; /* Read from the automatic gain control register. Arg: uint8_t* pointer. */ case QEIOC_AUTOGAINCTL: { FAR uint8_t *ptr = (FAR uint8_t *)((uintptr_t)arg); DEBUGASSERT(ptr != NULL); ret = as5048b_readagc(priv, ptr); sndbg("agc: %02x ret: %d\n", *ptr, ret); } break; /* Read from the diagnostics register. Arg: uint8_t* pointer. */ case QEIOC_DIAGNOSTICS: { FAR uint8_t *ptr = (FAR uint8_t *)((uintptr_t)arg); DEBUGASSERT(ptr != NULL); ret = as5048b_readdiag(priv, ptr); sndbg("diag: %02x ret: %d\n", *ptr, ret); } break; /* Read from the magnitude registers. Arg: int32_t* pointer. */ case QEIOC_MAGNITUDE: { FAR int32_t *ptr = (FAR int32_t *)((uintptr_t)arg); uint16_t mag; DEBUGASSERT(ptr != NULL); ret = as5048b_readmag(priv, &mag); if (ret == OK) { *ptr = (int32_t)mag; } sndbg("mag: %04x ret: %d\n", *ptr, ret); } break; default: sndbg("Unrecognized cmd: %d arg: %ld\n", cmd, arg); ret = -ENOTTY; break; } return ret; } /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: as5048b_initialize * * Description: * Initialize the AS5048B device. * * Input Parameters: * i2c - An I2C driver instance. * addr - The I2C address of the AS5048B. * * Returned Value: * A new lower half quadrature encoder interface for the AS5048B on success; * NULL on failure. * ****************************************************************************/ FAR struct qe_lowerhalf_s *as5048b_initialize(FAR struct i2c_master_s *i2c, uint8_t addr) { FAR struct as5048b_dev_s *priv; DEBUGASSERT(i2c != NULL); /* Initialize the device's structure */ priv = (FAR struct as5048b_dev_s *)kmm_malloc(sizeof(*priv)); if (priv == NULL) { sndbg("Failed to allocate instance\n"); return NULL; } priv->lower.ops = &g_qeops; priv->i2c = i2c; priv->addr = addr; return &priv->lower; } #endif /* CONFIG_I2C && CONFIG_QENCODER && CONFIG_AS5048B */