/**************************************************************************** * drivers/i2c/pca9540bdp.c * Driver for the PCA9540BDP i2c multiplexer * * Copyright (C) 2018 Giorgio Groß. All rights reserved. * Author: Giorgio Groß * * 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 #include #include "pca9540bdp.h" #include #ifdef CONFIG_I2CMULTIPLEXER_PCA9540BDP /**************************************************************************** * Private Function Prototypes ****************************************************************************/ /* I2C Helpers */ static int pca9540bdp_write_config(FAR struct pca9540bdp_dev_s *priv, FAR uint8_t regvalue); static int pca9540bdp_read_config(FAR struct pca9540bdp_dev_s *priv, FAR uint8_t *regvalue); /* Other helpers */ static int pca9540bdp_select_port(FAR struct pca9540bdp_dev_s *priv, uint8_t val); /* I2C multiplexer vtable */ static int pca9540bdp_transfer_on_port (FAR struct i2c_master_s *dev, FAR struct i2c_msg_s *msgs, int count); #ifdef CONFIG_I2C_RESET static int pca9540bdp_reset_on_port (FAR struct i2c_master_s *dev); #endif /**************************************************************************** * Private Data ****************************************************************************/ static const struct i2c_ops_s g_i2cmux_ops = { pca9540bdp_transfer_on_port #ifdef CONFIG_I2C_RESET , pca9540bdp_reset_on_port #endif }; /**************************************************************************** * Private Functions ****************************************************************************/ static int pca9540bdp_write_config(FAR struct pca9540bdp_dev_s *priv, FAR uint8_t regvalue) { struct i2c_config_s iconf; int ret; iconf.frequency = CONFIG_PCA9549BDP_I2C_FREQUENCY; iconf.address = priv->addr; iconf.addrlen = 7; ret = i2c_write(priv->i2c, &iconf, ®value, 1); i2cinfo("Write to address 0x%02X; register value: 0x%02x ret: %d\n", priv->addr, regvalue, ret); return ret; } static int pca9540bdp_read_config(FAR struct pca9540bdp_dev_s *priv, FAR uint8_t *regvalue) { struct i2c_config_s iconf; int ret; iconf.frequency = CONFIG_PCA9549BDP_I2C_FREQUENCY; iconf.address = priv->addr; iconf.addrlen = 7; ret = i2c_read(priv->i2c, &iconf, regvalue, 1); i2cinfo("Read from address: 0x%02X; register value: 0x%02x ret: %d\n", priv->addr, *regvalue, ret); return ret; } static int pca9540bdp_select_port(FAR struct pca9540bdp_dev_s *priv, uint8_t val) { if (val != PCA9540BDP_SEL_PORT0 && val != PCA9540BDP_SEL_PORT1) { /* port not supported */ return -EINVAL; } if ((PCA9540BDP_ENABLE | val) == priv->state) { /* port already selected */ return OK; } /* Modify state and write it to the mux. Selecting a port always enables * the device */ priv->state = PCA9540BDP_ENABLE | val; return (pca9540bdp_write_config(priv, priv->state) == 0) ? OK : -ECOMM; } static int pca9540bdp_transfer_on_port(FAR struct i2c_master_s *dev, FAR struct i2c_msg_s *msgs, int count) { FAR struct i2c_port_dev_s *port_dev = (FAR struct i2c_port_dev_s *)dev; FAR struct pca9540bdp_dev_s *priv = port_dev->dev; int ret; /* select the mux port */ if (pca9540bdp_select_port(priv, port_dev->port) != OK) { i2cerr("Could not select proper mux port\n"); return -ECOMM; /* Signal error condition */ } /* Resume the i2c transfer to the device connected to the mux port */ ret = I2C_TRANSFER(priv->i2c, msgs, count); i2cinfo("Selected port %d and resumed transfer. Result: %d\n", port_dev->port, ret); return ret; } #ifdef CONFIG_I2C_RESET static int pca9540bdp_reset_on_port (FAR struct i2c_master_s *dev) { FAR struct i2c_port_dev_s *port_dev = (struct i2c_port_dev_s *)dev; FAR struct pca9540bdp_dev_s *priv = port_dev->dev; int port = port_dev->port; int ret; /* select the mux port */ if (pca9540bdp_select_port(priv, port) != OK) { i2cerr("Could not select proper mux port\n"); return -ECOMM; /* signal error condition */ } /* resume the i2c reset for the device connected to the mux port */ ret = I2C_RESET(priv->i2c); return ret; } #endif /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: pca9540bdp_lower_half * * Description: * Initialize the lower half of the PCA9540BDP by creating a i2c_master_s * for the virtual i2c master and link it to the associated PCA9540BDP and * its port. * * Input Parameters: * dev - Pointer to the associated PCA9540BDP * port - The port number as defined in pca9540bdp.h * * Returned Value: * Common i2c multiplexer device instance; NULL on failure. * ****************************************************************************/ FAR struct i2c_master_s * pca9540bdp_lower_half(FAR struct pca9540bdp_dev_s *dev, uint8_t port) { FAR struct i2c_port_dev_s *port_dev; /* Sanity check */ DEBUGASSERT(dev != NULL); /* Initialize the i2c_port_dev_s device structure */ port_dev = (FAR struct i2c_port_dev_s *) kmm_malloc(sizeof(struct i2c_port_dev_s)); if (port_dev == NULL) { i2cerr("ERROR: Failed to allocate i2c port lower half instance\n"); return NULL; } /* set vi2c ops to their implementations */ port_dev->vi2c.ops = &g_i2cmux_ops; /* save state variables */ port_dev->dev = dev; port_dev->port = port; return &port_dev->vi2c; } /**************************************************************************** * Name: pca9540bdp_initialize * * Description: * Initialize the PCA9540BDP device. * * Input Parameters: * i2c - An instance of the I2C interface to use to communicate with * PCA9540BDP * addr - The I2C address of the PCA9540BDP. The base I2C address of the * PCA9540BDP is 0x70. * * Returned Value: * Common i2c multiplexer device instance; NULL on failure. * ****************************************************************************/ FAR struct pca9540bdp_dev_s * pca9540bdp_initialize(FAR struct i2c_master_s *i2c, uint8_t addr) { FAR struct pca9540bdp_dev_s *priv; /* Sanity check */ DEBUGASSERT(i2c != NULL); /* Initialize the PCA9549BDP device structure */ priv = (FAR struct pca9540bdp_dev_s *) kmm_malloc(sizeof(struct pca9540bdp_dev_s)); if (priv == NULL) { i2cerr("ERROR: Failed to allocate instance\n"); return NULL; } priv->i2c = i2c; priv->addr = addr; priv->state = 0x00; if (pca9540bdp_read_config(priv, &priv->state) != OK) { i2cerr("Could not read initial state from the device\n"); kmm_free(priv); return NULL; /* signal error condition */ } i2cinfo("Initial device state: %d\n", priv->state); if (pca9540bdp_select_port(priv, PCA9540BDP_SEL_PORT0) != OK) { i2cerr("Could not select mux port 0\n"); kmm_free(priv); return NULL; /* signal error condition */ } i2cinfo("PCA9549BDP (addr=0x%02x) set up with port %d\n", priv->addr, PCA9540BDP_SEL_PORT0); return priv; } #endif /* CONFIG_I2CMULTIPLEXER_PCA9540BDP */