Index: head/sys/dev/iicbus/twsi/twsi.c =================================================================== --- head/sys/dev/iicbus/twsi/twsi.c (revision 320160) +++ head/sys/dev/iicbus/twsi/twsi.c (revision 320161) @@ -1,481 +1,485 @@ /*- * Copyright (C) 2008 MARVELL INTERNATIONAL LTD. * All rights reserved. * * Developed by Semihalf. * * 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 of MARVELL nor the names of contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY AUTHOR 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 AUTHOR 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. */ /* * Driver for the TWSI (aka I2C, aka IIC) bus controller found on Marvell * and Allwinner SoCs. Supports master operation only, and works in polling mode. * * Calls to DELAY() are needed per Application Note AN-179 "TWSI Software * Guidelines for Discovery(TM), Horizon (TM) and Feroceon(TM) Devices". */ #include __FBSDID("$FreeBSD$"); #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "iicbus_if.h" #define TWSI_CONTROL_ACK (1 << 2) #define TWSI_CONTROL_IFLG (1 << 3) #define TWSI_CONTROL_STOP (1 << 4) #define TWSI_CONTROL_START (1 << 5) #define TWSI_CONTROL_TWSIEN (1 << 6) #define TWSI_CONTROL_INTEN (1 << 7) #define TWSI_STATUS_START 0x08 #define TWSI_STATUS_RPTD_START 0x10 #define TWSI_STATUS_ADDR_W_ACK 0x18 #define TWSI_STATUS_DATA_WR_ACK 0x28 #define TWSI_STATUS_ADDR_R_ACK 0x40 #define TWSI_STATUS_DATA_RD_ACK 0x50 #define TWSI_STATUS_DATA_RD_NOACK 0x58 #define TWSI_DEBUG #undef TWSI_DEBUG #ifdef TWSI_DEBUG #define debugf(fmt, args...) do { printf("%s(): ", __func__); printf(fmt,##args); } while (0) #else #define debugf(fmt, args...) #endif static struct resource_spec res_spec[] = { { SYS_RES_MEMORY, 0, RF_ACTIVE }, { -1, 0 } }; static __inline uint32_t TWSI_READ(struct twsi_softc *sc, bus_size_t off) { return (bus_read_4(sc->res[0], off)); } static __inline void TWSI_WRITE(struct twsi_softc *sc, bus_size_t off, uint32_t val) { bus_write_4(sc->res[0], off, val); } static __inline void twsi_control_clear(struct twsi_softc *sc, uint32_t mask) { uint32_t val; val = TWSI_READ(sc, sc->reg_control); + val &= ~(TWSI_CONTROL_STOP | TWSI_CONTROL_START); val &= ~mask; TWSI_WRITE(sc, sc->reg_control, val); } static __inline void twsi_control_set(struct twsi_softc *sc, uint32_t mask) { uint32_t val; val = TWSI_READ(sc, sc->reg_control); + val &= ~(TWSI_CONTROL_STOP | TWSI_CONTROL_START); val |= mask; TWSI_WRITE(sc, sc->reg_control, val); } static __inline void twsi_clear_iflg(struct twsi_softc *sc) { DELAY(1000); twsi_control_clear(sc, TWSI_CONTROL_IFLG); DELAY(1000); } /* * timeout given in us * returns * 0 on successful mask change * non-zero on timeout */ static int twsi_poll_ctrl(struct twsi_softc *sc, int timeout, uint32_t mask) { timeout /= 10; while (!(TWSI_READ(sc, sc->reg_control) & mask)) { DELAY(10); if (--timeout < 0) return (timeout); } return (0); } /* * 'timeout' is given in us. Note also that timeout handling is not exact -- * twsi_locked_start() total wait can be more than 2 x timeout * (twsi_poll_ctrl() is called twice). 'mask' can be either TWSI_STATUS_START * or TWSI_STATUS_RPTD_START */ static int twsi_locked_start(device_t dev, struct twsi_softc *sc, int32_t mask, u_char slave, int timeout) { int read_access, iflg_set = 0; uint32_t status; mtx_assert(&sc->mutex, MA_OWNED); if (mask == TWSI_STATUS_RPTD_START) /* read IFLG to know if it should be cleared later; from NBSD */ iflg_set = TWSI_READ(sc, sc->reg_control) & TWSI_CONTROL_IFLG; twsi_control_set(sc, TWSI_CONTROL_START); if (mask == TWSI_STATUS_RPTD_START && iflg_set) { debugf("IFLG set, clearing\n"); twsi_clear_iflg(sc); } /* * Without this delay we timeout checking IFLG if the timeout is 0. * NBSD driver always waits here too. */ DELAY(1000); if (twsi_poll_ctrl(sc, timeout, TWSI_CONTROL_IFLG)) { debugf("timeout sending %sSTART condition\n", mask == TWSI_STATUS_START ? "" : "repeated "); return (IIC_ETIMEOUT); } status = TWSI_READ(sc, sc->reg_status); if (status != mask) { debugf("wrong status (%02x) after sending %sSTART condition\n", status, mask == TWSI_STATUS_START ? "" : "repeated "); return (IIC_ESTATUS); } TWSI_WRITE(sc, sc->reg_data, slave); - DELAY(1000); twsi_clear_iflg(sc); + DELAY(1000); if (twsi_poll_ctrl(sc, timeout, TWSI_CONTROL_IFLG)) { debugf("timeout sending slave address\n"); return (IIC_ETIMEOUT); } read_access = (slave & 0x1) ? 1 : 0; status = TWSI_READ(sc, sc->reg_status); if (status != (read_access ? TWSI_STATUS_ADDR_R_ACK : TWSI_STATUS_ADDR_W_ACK)) { debugf("no ACK (status: %02x) after sending slave address\n", status); return (IIC_ENOACK); } return (IIC_NOERR); } /* * Only slave mode supported, disregard [old]addr */ static int twsi_reset(device_t dev, u_char speed, u_char addr, u_char *oldaddr) { struct twsi_softc *sc; uint32_t param; sc = device_get_softc(dev); switch (speed) { case IIC_SLOW: case IIC_FAST: param = sc->baud_rate[speed].param; break; case IIC_FASTEST: case IIC_UNKNOWN: default: param = sc->baud_rate[IIC_FAST].param; break; } mtx_lock(&sc->mutex); TWSI_WRITE(sc, sc->reg_soft_reset, 0x0); DELAY(2000); TWSI_WRITE(sc, sc->reg_baud_rate, param); - TWSI_WRITE(sc, sc->reg_control, TWSI_CONTROL_TWSIEN | TWSI_CONTROL_ACK); + TWSI_WRITE(sc, sc->reg_control, TWSI_CONTROL_TWSIEN); DELAY(1000); mtx_unlock(&sc->mutex); return (0); } static int twsi_stop(device_t dev) { struct twsi_softc *sc; sc = device_get_softc(dev); mtx_lock(&sc->mutex); + twsi_control_clear(sc, TWSI_CONTROL_ACK); twsi_control_set(sc, TWSI_CONTROL_STOP); - DELAY(1000); twsi_clear_iflg(sc); + DELAY(1000); mtx_unlock(&sc->mutex); return (IIC_NOERR); } /* * timeout is given in us */ static int twsi_repeated_start(device_t dev, u_char slave, int timeout) { struct twsi_softc *sc; int rv; sc = device_get_softc(dev); mtx_lock(&sc->mutex); rv = twsi_locked_start(dev, sc, TWSI_STATUS_RPTD_START, slave, timeout); mtx_unlock(&sc->mutex); if (rv) { twsi_stop(dev); return (rv); } else return (IIC_NOERR); } /* * timeout is given in us */ static int twsi_start(device_t dev, u_char slave, int timeout) { struct twsi_softc *sc; int rv; sc = device_get_softc(dev); mtx_lock(&sc->mutex); rv = twsi_locked_start(dev, sc, TWSI_STATUS_START, slave, timeout); mtx_unlock(&sc->mutex); if (rv) { twsi_stop(dev); return (rv); } else return (IIC_NOERR); } static int twsi_read(device_t dev, char *buf, int len, int *read, int last, int delay) { struct twsi_softc *sc; uint32_t status; int last_byte, rv; sc = device_get_softc(dev); mtx_lock(&sc->mutex); *read = 0; while (*read < len) { /* * Check if we are reading last byte of the last buffer, * do not send ACK then, per I2C specs */ last_byte = ((*read == len - 1) && last) ? 1 : 0; if (last_byte) twsi_control_clear(sc, TWSI_CONTROL_ACK); else twsi_control_set(sc, TWSI_CONTROL_ACK); - DELAY (1000); twsi_clear_iflg(sc); + DELAY(1000); if (twsi_poll_ctrl(sc, delay, TWSI_CONTROL_IFLG)) { debugf("timeout reading data\n"); rv = IIC_ETIMEOUT; goto out; } status = TWSI_READ(sc, sc->reg_status); if (status != (last_byte ? TWSI_STATUS_DATA_RD_NOACK : TWSI_STATUS_DATA_RD_ACK)) { debugf("wrong status (%02x) while reading\n", status); rv = IIC_ESTATUS; goto out; } *buf++ = TWSI_READ(sc, sc->reg_data); (*read)++; } rv = IIC_NOERR; out: mtx_unlock(&sc->mutex); return (rv); } static int twsi_write(device_t dev, const char *buf, int len, int *sent, int timeout) { struct twsi_softc *sc; uint32_t status; int rv; sc = device_get_softc(dev); mtx_lock(&sc->mutex); *sent = 0; while (*sent < len) { TWSI_WRITE(sc, sc->reg_data, *buf++); twsi_clear_iflg(sc); + DELAY(1000); if (twsi_poll_ctrl(sc, timeout, TWSI_CONTROL_IFLG)) { debugf("timeout writing data\n"); rv = IIC_ETIMEOUT; goto out; } status = TWSI_READ(sc, sc->reg_status); if (status != TWSI_STATUS_DATA_WR_ACK) { debugf("wrong status (%02x) while writing\n", status); rv = IIC_ESTATUS; goto out; } (*sent)++; } rv = IIC_NOERR; out: mtx_unlock(&sc->mutex); return (rv); } int twsi_attach(device_t dev) { struct twsi_softc *sc; sc = device_get_softc(dev); sc->dev = dev; mtx_init(&sc->mutex, device_get_nameunit(dev), "twsi", MTX_DEF); if (bus_alloc_resources(dev, res_spec, sc->res)) { device_printf(dev, "could not allocate resources\n"); twsi_detach(dev); return (ENXIO); } /* Attach the iicbus. */ if ((sc->iicbus = device_add_child(dev, "iicbus", -1)) == NULL) { device_printf(dev, "could not allocate iicbus instance\n"); twsi_detach(dev); return (ENXIO); } bus_generic_attach(dev); return (0); } int twsi_detach(device_t dev) { struct twsi_softc *sc; int rv; sc = device_get_softc(dev); if ((rv = bus_generic_detach(dev)) != 0) return (rv); if (sc->iicbus != NULL) if ((rv = device_delete_child(dev, sc->iicbus)) != 0) return (rv); bus_release_resources(dev, res_spec, sc->res); mtx_destroy(&sc->mutex); return (0); } static device_method_t twsi_methods[] = { /* device interface */ DEVMETHOD(device_detach, twsi_detach), /* Bus interface */ DEVMETHOD(bus_setup_intr, bus_generic_setup_intr), DEVMETHOD(bus_teardown_intr, bus_generic_teardown_intr), DEVMETHOD(bus_alloc_resource, bus_generic_alloc_resource), DEVMETHOD(bus_release_resource, bus_generic_release_resource), DEVMETHOD(bus_activate_resource, bus_generic_activate_resource), DEVMETHOD(bus_deactivate_resource, bus_generic_deactivate_resource), DEVMETHOD(bus_adjust_resource, bus_generic_adjust_resource), DEVMETHOD(bus_set_resource, bus_generic_rl_set_resource), DEVMETHOD(bus_get_resource, bus_generic_rl_get_resource), /* iicbus interface */ DEVMETHOD(iicbus_callback, iicbus_null_callback), DEVMETHOD(iicbus_repeated_start, twsi_repeated_start), DEVMETHOD(iicbus_start, twsi_start), DEVMETHOD(iicbus_stop, twsi_stop), DEVMETHOD(iicbus_write, twsi_write), DEVMETHOD(iicbus_read, twsi_read), DEVMETHOD(iicbus_reset, twsi_reset), DEVMETHOD(iicbus_transfer, iicbus_transfer_gen), { 0, 0 } }; DEFINE_CLASS_0(twsi, twsi_driver, twsi_methods, sizeof(struct twsi_softc));