/* $NetBSD: nslu2_iic.c,v 1.5 2008/04/28 20:23:17 martin Exp $ */ /*- * Copyright (c) 2006 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Steve C. Woodford. * * 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. * * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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. */ #include #include #include #include #include #include #include #include #include #include #include struct slugiic_softc { struct device sc_dev; struct i2c_controller sc_ic; struct i2c_bitbang_ops sc_ibo; kmutex_t sc_lock; #ifdef DIAGNOSTIC uint32_t sc_dirout; #endif }; static int slugiic_acquire_bus(void *arg, int flags) { struct slugiic_softc *sc = arg; if (flags & I2C_F_POLL) return (0); mutex_enter(&sc->sc_lock); return (0); } static void slugiic_release_bus(void *arg, int flags) { struct slugiic_softc *sc = arg; if (flags & I2C_F_POLL) return; mutex_exit(&sc->sc_lock); } static int slugiic_send_start(void *arg, int flags) { struct slugiic_softc *sc = arg; return (i2c_bitbang_send_start(sc, flags, &sc->sc_ibo)); } static int slugiic_send_stop(void *arg, int flags) { struct slugiic_softc *sc = arg; return (i2c_bitbang_send_stop(sc, flags, &sc->sc_ibo)); } static int slugiic_initiate_xfer(void *arg, i2c_addr_t addr, int flags) { struct slugiic_softc *sc = arg; return (i2c_bitbang_initiate_xfer(sc, addr, flags, &sc->sc_ibo)); } static int slugiic_read_byte(void *arg, uint8_t *vp, int flags) { struct slugiic_softc *sc = arg; return (i2c_bitbang_read_byte(sc, vp, flags, &sc->sc_ibo)); } static int slugiic_write_byte(void *arg, uint8_t v, int flags) { struct slugiic_softc *sc = arg; return (i2c_bitbang_write_byte(sc, v, flags, &sc->sc_ibo)); } static void slugiic_set_dir(void *arg, uint32_t bits) { #ifdef DIAGNOSTIC struct slugiic_softc *sc = arg; sc->sc_dirout = bits; #endif } static void slugiic_set_bits(void *arg, uint32_t bits) { uint32_t reg; int s; #ifdef DIAGNOSTIC struct slugiic_softc *sc = arg; if (sc->sc_dirout == 0 && (bits & GPIO_I2C_SDA_BIT) == 0) { printf("slugiic_set_bits: SDA low in input mode!\n"); bits |= GPIO_I2C_SDA_BIT; } #endif s = splhigh(); reg = GPIO_CONF_READ_4(ixp425_softc, IXP425_GPIO_GPOUTR); reg &= ~(GPIO_I2C_SDA_BIT | GPIO_I2C_SCL_BIT); GPIO_CONF_WRITE_4(ixp425_softc, IXP425_GPIO_GPOUTR, reg | bits); /* * Enable output only if the SDA/SCL lines are to be driven low. * Otherwise switch to input and allow the pullup resistors * to hold them high. */ reg = GPIO_CONF_READ_4(ixp425_softc, IXP425_GPIO_GPOER); reg &= ~(GPIO_I2C_SDA_BIT | GPIO_I2C_SCL_BIT); reg |= bits & (GPIO_I2C_SDA_BIT | GPIO_I2C_SCL_BIT); GPIO_CONF_WRITE_4(ixp425_softc, IXP425_GPIO_GPOER, reg); splx(s); } static uint32_t slugiic_read_bits(void *arg) { uint32_t reg; #ifdef DIAGNOSTIC struct slugiic_softc *sc = arg; if (sc->sc_dirout) printf("slugiic_read_bits: Read in output mode\n"); #endif reg = GPIO_CONF_READ_4(ixp425_softc, IXP425_GPIO_GPINR); return (reg & (GPIO_I2C_SDA_BIT | GPIO_I2C_SCL_BIT)); } static void slugiic_deferred_attach(struct device *device) { struct slugiic_softc *sc = (struct slugiic_softc *)device; struct i2cbus_attach_args iba; uint32_t reg; reg = GPIO_CONF_READ_4(ixp425_softc, IXP425_GPIO_GPOUTR); reg |= GPIO_I2C_SDA_BIT | GPIO_I2C_SCL_BIT; GPIO_CONF_WRITE_4(ixp425_softc, IXP425_GPIO_GPOUTR, reg); reg = GPIO_CONF_READ_4(ixp425_softc, IXP425_GPIO_GPOER); reg &= ~GPIO_I2C_SCL_BIT; reg |= GPIO_I2C_SDA_BIT; GPIO_CONF_WRITE_4(ixp425_softc, IXP425_GPIO_GPOER, reg); iba.iba_tag = &sc->sc_ic; (void) config_found_ia(&sc->sc_dev, "i2cbus", &iba, iicbus_print); } static int slugiic_match(struct device *parent, struct cfdata *cf, void *arg) { return (1); } static void slugiic_attach(struct device *parent, struct device *self, void *arg) { struct slugiic_softc *sc = (struct slugiic_softc *)self; aprint_naive("\n"); aprint_normal(": I2C bus\n"); sc->sc_ic.ic_cookie = sc; sc->sc_ic.ic_acquire_bus = slugiic_acquire_bus; sc->sc_ic.ic_release_bus = slugiic_release_bus; sc->sc_ic.ic_exec = NULL; sc->sc_ic.ic_send_start = slugiic_send_start; sc->sc_ic.ic_send_stop = slugiic_send_stop; sc->sc_ic.ic_initiate_xfer = slugiic_initiate_xfer; sc->sc_ic.ic_read_byte = slugiic_read_byte; sc->sc_ic.ic_write_byte = slugiic_write_byte; sc->sc_ibo.ibo_set_dir = slugiic_set_dir; sc->sc_ibo.ibo_set_bits = slugiic_set_bits; sc->sc_ibo.ibo_read_bits = slugiic_read_bits; sc->sc_ibo.ibo_bits[I2C_BIT_SDA] = GPIO_I2C_SDA_BIT; sc->sc_ibo.ibo_bits[I2C_BIT_SCL] = GPIO_I2C_SCL_BIT; sc->sc_ibo.ibo_bits[I2C_BIT_OUTPUT] = 1; sc->sc_ibo.ibo_bits[I2C_BIT_INPUT] = 0; mutex_init(&sc->sc_lock, MUTEX_DEFAULT, IPL_NONE); #ifdef DIAGNOSTIC sc->sc_dirout = 0; #endif /* * Defer until ixp425_softc has been initialised */ config_interrupts(self, slugiic_deferred_attach); } CFATTACH_DECL(slugiic, sizeof(struct slugiic_softc), slugiic_match, slugiic_attach, NULL, NULL);