/* $NetBSD: gttwsi.c,v 1.1 2010/04/28 13:51:56 kiyohara Exp $ */ /* * Copyright (c) 2008 Eiji Kawauchi. * All rights reserved. * * 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. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed for the NetBSD Project by * Eiji Kawauchi. * 4. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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. */ /* * Copyright (c) 2005 Brocade Communcations, inc. * All rights reserved. * * Written by Matt Thomas for Brocade Communcations, Inc. * * 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. The name of Brocade Communications, Inc. may not be used to endorse * or promote products derived from this software without specific prior * written permission. * * THIS SOFTWARE IS PROVIDED BY BROCADE COMMUNICATIONS, INC. ``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 EITHER BROCADE COMMUNICATIONS, INC. 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. */ //#define TWSI_DEBUG /* * Marvell Two-Wire Serial Interface (aka I2C) master driver */ #include __KERNEL_RCSID(0, "$NetBSD: gttwsi.c,v 1.1 2010/04/28 13:51:56 kiyohara Exp $"); #include "locators.h" #include #include #include #include #include #include #include #include #include #include #include #include #include struct gttwsi_softc { device_t sc_dev; bus_space_tag_t sc_bust; bus_space_handle_t sc_bush; uint8_t sc_started; struct i2c_controller sc_i2c; kmutex_t sc_buslock; kmutex_t sc_mtx; kcondvar_t sc_cv; }; static int gttwsi_match(device_t, cfdata_t, void *); static void gttwsi_attach(device_t, device_t, void *); static int gttwsi_intr(void *); static int gttwsi_acquire_bus(void *, int); static void gttwsi_release_bus(void *, int); static int gttwsi_send_start(void *v, int flags); static int gttwsi_send_stop(void *v, int flags); static int gttwsi_initiate_xfer(void *v, i2c_addr_t addr, int flags); static int gttwsi_read_byte(void *v, uint8_t *valp, int flags); static int gttwsi_write_byte(void *v, uint8_t val, int flags); static int gttwsi_wait(struct gttwsi_softc *, uint32_t, uint32_t, int); static __inline u_int32_t RREG(struct gttwsi_softc *, u_int32_t); static __inline void WREG(struct gttwsi_softc *, u_int32_t, u_int32_t); CFATTACH_DECL_NEW(gttwsi_gt, sizeof(struct gttwsi_softc), gttwsi_match, gttwsi_attach, NULL, NULL); CFATTACH_DECL_NEW(gttwsi_mbus, sizeof(struct gttwsi_softc), gttwsi_match, gttwsi_attach, NULL, NULL); static __inline u_int32_t RREG(struct gttwsi_softc *sc, u_int32_t reg) { u_int32_t val; val = bus_space_read_4(sc->sc_bust, sc->sc_bush, reg); #ifdef TWSI_DEBUG printf("I2C:R:%02x:%02x\n", reg, val); #else DELAY(TWSI_READ_DELAY); #endif return val; } static __inline void WREG(struct gttwsi_softc *sc, u_int32_t reg, u_int32_t val) { bus_space_write_4(sc->sc_bust, sc->sc_bush, reg, val); #ifdef TWSI_DEBUG printf("I2C:W:%02x:%02x\n", reg, val); #else DELAY(TWSI_WRITE_DELAY); #endif return; } /* ARGSUSED */ static int gttwsi_match(device_t parent, cfdata_t match, void *aux) { struct marvell_attach_args *mva = aux; if (strcmp(mva->mva_name, match->cf_name) != 0) return 0; if (mva->mva_offset == GTCF_OFFSET_DEFAULT || mva->mva_irq == GTCF_IRQ_DEFAULT) return 0; mva->mva_size = GTTWSI_SIZE; return 1; } /* ARGSUSED */ static void gttwsi_attach(device_t parent, device_t self, void *args) { struct gttwsi_softc *sc = device_private(self); struct marvell_attach_args *mva = args; struct i2cbus_attach_args iba; aprint_naive("\n"); aprint_normal(": Marvell TWSI controller\n"); sc->sc_dev = self; sc->sc_bust = mva->mva_iot; if (bus_space_subregion(mva->mva_iot, mva->mva_ioh, mva->mva_offset, mva->mva_size, &sc->sc_bush)) { aprint_error_dev(self, "Cannot map registers\n"); return; } mutex_init(&sc->sc_buslock, MUTEX_DEFAULT, IPL_NONE); mutex_init(&sc->sc_mtx, MUTEX_DEFAULT, IPL_BIO); cv_init(&sc->sc_cv, "gttwsi"); sc->sc_started = 0; sc->sc_i2c.ic_cookie = sc; sc->sc_i2c.ic_acquire_bus = gttwsi_acquire_bus; sc->sc_i2c.ic_release_bus = gttwsi_release_bus; sc->sc_i2c.ic_exec = NULL; sc->sc_i2c.ic_send_start = gttwsi_send_start; sc->sc_i2c.ic_send_stop = gttwsi_send_stop; sc->sc_i2c.ic_initiate_xfer = gttwsi_initiate_xfer; sc->sc_i2c.ic_read_byte = gttwsi_read_byte; sc->sc_i2c.ic_write_byte = gttwsi_write_byte; marvell_intr_establish(mva->mva_irq, IPL_BIO, gttwsi_intr, sc); /* * Put the controller into Soft Reset. */ /* reset */ WREG(sc, TWSI_SOFTRESET, SOFTRESET_VAL); memset(&iba, 0, sizeof(iba)); iba.iba_tag = &sc->sc_i2c; (void) config_found_ia(sc->sc_dev, "i2cbus", &iba, iicbus_print); } static int gttwsi_intr(void *arg) { struct gttwsi_softc *sc = arg; uint32_t val; val = RREG(sc, TWSI_CONTROL); if (val & CONTROL_IFLG) { WREG(sc, TWSI_CONTROL, val & ~CONTROL_INTEN); mutex_enter(&sc->sc_mtx); cv_signal(&sc->sc_cv); mutex_exit(&sc->sc_mtx); return 1; /* handled */ } return 0; } /* ARGSUSED */ static int gttwsi_acquire_bus(void *arg, int flags) { struct gttwsi_softc *sc = arg; mutex_enter(&sc->sc_buslock); return 0; } /* ARGSUSED */ static void gttwsi_release_bus(void *arg, int flags) { struct gttwsi_softc *sc = arg; mutex_exit(&sc->sc_buslock); } static int gttwsi_send_start(void *v, int flags) { struct gttwsi_softc *sc = v; int expect; if (sc->sc_started) expect = STAT_RSCT; else expect = STAT_SCT; sc->sc_started = 1; return gttwsi_wait(sc, CONTROL_START, expect, flags); } static int gttwsi_send_stop(void *v, int flags) { struct gttwsi_softc *sc = v; int retry = TWSI_RETRY_COUNT; sc->sc_started = 0; /* Interrupt is not generated for STAT_NRS. */ WREG(sc, TWSI_CONTROL, CONTROL_STOP | CONTROL_TWSIEN); while (retry > 0) { if (RREG(sc, TWSI_STATUS) == STAT_NRS) return 0; retry--; DELAY(TWSI_STAT_DELAY); } aprint_error_dev(sc->sc_dev, "send STOP failed\n"); return -1; } static int gttwsi_initiate_xfer(void *v, i2c_addr_t addr, int flags) { struct gttwsi_softc *sc = v; uint32_t data, expect; int error, read; gttwsi_send_start(v, flags); read = (flags & I2C_F_READ) != 0; if (read) expect = STAT_ARBT_AR; else expect = STAT_AWBT_AR; /* * First byte contains whether this xfer is a read or write. */ data = read; if (addr > 0x7f) { /* * If this is a 10bit request, the first address byte is * 0b11110. */ data |= 0xf0 | ((addr & 0x300) >> 7); WREG(sc, TWSI_DATA, data); error = gttwsi_wait(sc, 0, expect, flags); if (error) return error; /* * The first address byte has been sent, now to send * the second one. */ if (read) expect = STAT_SARBT_AR; else expect = STAT_SAWBT_AR; data = (uint8_t)addr; } else data |= (addr << 1); WREG(sc, TWSI_DATA, data); return gttwsi_wait(sc, 0, expect, flags); } static int gttwsi_read_byte(void *v, uint8_t *valp, int flags) { struct gttwsi_softc *sc = v; int error; error = gttwsi_wait(sc, CONTROL_ACK, STAT_MRRD_AT, flags); if (!error) *valp = RREG(sc, TWSI_DATA); if (flags & I2C_F_LAST) WREG(sc, TWSI_CONTROL, 0); return error; } static int gttwsi_write_byte(void *v, uint8_t val, int flags) { struct gttwsi_softc *sc = v; WREG(sc, TWSI_DATA, val); return gttwsi_wait(sc, 0, STAT_MTDB_AR, flags); } static int gttwsi_wait(struct gttwsi_softc *sc, uint32_t control, uint32_t expect, int flags) { uint32_t status; int error = 0; DELAY(5); if (!(flags & I2C_F_POLL)) control |= CONTROL_INTEN; WREG(sc, TWSI_CONTROL, control | CONTROL_TWSIEN); for (;;) { control = RREG(sc, TWSI_CONTROL); if (control & CONTROL_IFLG) break; if (!(flags & I2C_F_POLL)) { mutex_enter(&sc->sc_mtx); error = cv_timedwait_sig(&sc->sc_cv, &sc->sc_mtx, hz); mutex_exit(&sc->sc_mtx); if (error) return error; } DELAY(TWSI_RETRY_DELAY); } status = RREG(sc, TWSI_STATUS); if (status != expect) { aprint_error_dev(sc->sc_dev, "unexpected status 0x%x: expect 0x%x\n", status, expect); return EIO; } if ((flags & I2C_F_STOP) && expect != STAT_MRRD_AT) error = gttwsi_send_stop(sc, flags); return error; }