diff options
Diffstat (limited to 'sys/dev/iicbus/iicsmb.c')
| -rw-r--r-- | sys/dev/iicbus/iicsmb.c | 513 |
1 files changed, 513 insertions, 0 deletions
diff --git a/sys/dev/iicbus/iicsmb.c b/sys/dev/iicbus/iicsmb.c new file mode 100644 index 0000000..966063f --- /dev/null +++ b/sys/dev/iicbus/iicsmb.c @@ -0,0 +1,513 @@ +/*- + * Copyright (c) 1998, 2001 Nicolas Souchu + * 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. + * + * THIS SOFTWARE IS PROVIDED BY THE 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 THE 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. + * + * $FreeBSD$ + * + */ + +/* + * I2C to SMB bridge + * + * Example: + * + * smb bttv + * \ / + * smbus + * / \ + * iicsmb bti2c + * | + * iicbus + * / | \ + * iicbb pcf ... + * | + * lpbb + */ + +#include <sys/param.h> +#include <sys/kernel.h> +#include <sys/systm.h> +#include <sys/module.h> +#include <sys/bus.h> +#include <sys/uio.h> + + +#include <dev/iicbus/iiconf.h> +#include <dev/iicbus/iicbus.h> + +#include <dev/smbus/smbconf.h> + +#include "iicbus_if.h" +#include "smbus_if.h" + +struct iicsmb_softc { + +#define SMB_WAITING_ADDR 0x0 +#define SMB_WAITING_LOW 0x1 +#define SMB_WAITING_HIGH 0x2 +#define SMB_DONE 0x3 + int state; + + u_char devaddr; /* slave device address */ + + char low; /* low byte received first */ + char high; /* high byte */ + + device_t smbus; +}; + +static int iicsmb_probe(device_t); +static int iicsmb_attach(device_t); +static int iicsmb_detach(device_t); +static void iicsmb_identify(driver_t *driver, device_t parent); + +static void iicsmb_intr(device_t dev, int event, char *buf); +static int iicsmb_callback(device_t dev, int index, caddr_t data); +static int iicsmb_quick(device_t dev, u_char slave, int how); +static int iicsmb_sendb(device_t dev, u_char slave, char byte); +static int iicsmb_recvb(device_t dev, u_char slave, char *byte); +static int iicsmb_writeb(device_t dev, u_char slave, char cmd, char byte); +static int iicsmb_writew(device_t dev, u_char slave, char cmd, short word); +static int iicsmb_readb(device_t dev, u_char slave, char cmd, char *byte); +static int iicsmb_readw(device_t dev, u_char slave, char cmd, short *word); +static int iicsmb_pcall(device_t dev, u_char slave, char cmd, short sdata, short *rdata); +static int iicsmb_bwrite(device_t dev, u_char slave, char cmd, u_char count, char *buf); +static int iicsmb_bread(device_t dev, u_char slave, char cmd, u_char count, char *buf); + +static devclass_t iicsmb_devclass; + +static device_method_t iicsmb_methods[] = { + /* device interface */ + DEVMETHOD(device_identify, iicsmb_identify), + DEVMETHOD(device_probe, iicsmb_probe), + DEVMETHOD(device_attach, iicsmb_attach), + DEVMETHOD(device_detach, iicsmb_detach), + + /* bus interface */ + DEVMETHOD(bus_driver_added, bus_generic_driver_added), + DEVMETHOD(bus_print_child, bus_generic_print_child), + + /* iicbus interface */ + DEVMETHOD(iicbus_intr, iicsmb_intr), + + /* smbus interface */ + DEVMETHOD(smbus_callback, iicsmb_callback), + DEVMETHOD(smbus_quick, iicsmb_quick), + DEVMETHOD(smbus_sendb, iicsmb_sendb), + DEVMETHOD(smbus_recvb, iicsmb_recvb), + DEVMETHOD(smbus_writeb, iicsmb_writeb), + DEVMETHOD(smbus_writew, iicsmb_writew), + DEVMETHOD(smbus_readb, iicsmb_readb), + DEVMETHOD(smbus_readw, iicsmb_readw), + DEVMETHOD(smbus_pcall, iicsmb_pcall), + DEVMETHOD(smbus_bwrite, iicsmb_bwrite), + DEVMETHOD(smbus_bread, iicsmb_bread), + + { 0, 0 } +}; + +static driver_t iicsmb_driver = { + "iicsmb", + iicsmb_methods, + sizeof(struct iicsmb_softc), +}; + +#define IICBUS_TIMEOUT 100 /* us */ + +static void +iicsmb_identify(driver_t *driver, device_t parent) +{ + BUS_ADD_CHILD(parent, 0, "iicsmb", -1); +} + +static int +iicsmb_probe(device_t dev) +{ + device_set_desc(dev, "SMBus over I2C bridge"); + return (0); +} + +static int +iicsmb_attach(device_t dev) +{ + struct iicsmb_softc *sc = (struct iicsmb_softc *)device_get_softc(dev); + + bzero(sc, sizeof(*sc)); + + sc->smbus = device_add_child(dev, "smbus", -1); + + /* probe and attach the smbus */ + bus_generic_attach(dev); + + return (0); +} + +static int +iicsmb_detach(device_t dev) +{ + struct iicsmb_softc *sc = (struct iicsmb_softc *)device_get_softc(dev); + + bus_generic_detach(dev); + if (sc->smbus) { + device_delete_child(dev, sc->smbus); + } + + return (0); +} + +/* + * iicsmb_intr() + * + * iicbus interrupt handler + */ +static void +iicsmb_intr(device_t dev, int event, char *buf) +{ + struct iicsmb_softc *sc = (struct iicsmb_softc *)device_get_softc(dev); + + switch (event) { + case INTR_GENERAL: + case INTR_START: + sc->state = SMB_WAITING_ADDR; + break; + + case INTR_STOP: + /* call smbus intr handler */ + smbus_intr(sc->smbus, sc->devaddr, + sc->low, sc->high, SMB_ENOERR); + break; + + case INTR_RECEIVE: + switch (sc->state) { + case SMB_DONE: + /* XXX too much data, discard */ + printf("%s: too much data from 0x%x\n", __func__, + sc->devaddr & 0xff); + goto end; + + case SMB_WAITING_ADDR: + sc->devaddr = (u_char)*buf; + sc->state = SMB_WAITING_LOW; + break; + + case SMB_WAITING_LOW: + sc->low = *buf; + sc->state = SMB_WAITING_HIGH; + break; + + case SMB_WAITING_HIGH: + sc->high = *buf; + sc->state = SMB_DONE; + break; + } +end: + break; + + case INTR_TRANSMIT: + case INTR_NOACK: + break; + + case INTR_ERROR: + switch (*buf) { + case IIC_EBUSERR: + smbus_intr(sc->smbus, sc->devaddr, 0, 0, SMB_EBUSERR); + break; + + default: + printf("%s unknown error 0x%x!\n", __func__, + (int)*buf); + break; + } + break; + + default: + panic("%s: unknown event (%d)!", __func__, event); + } + + return; +} + +static int +iicsmb_callback(device_t dev, int index, caddr_t data) +{ + device_t parent = device_get_parent(dev); + int error = 0; + int how; + + switch (index) { + case SMB_REQUEST_BUS: + /* request underlying iicbus */ + how = *(int *)data; + error = iicbus_request_bus(parent, dev, how); + break; + + case SMB_RELEASE_BUS: + /* release underlying iicbus */ + error = iicbus_release_bus(parent, dev); + break; + + default: + error = EINVAL; + } + + return (error); +} + +static int +iicsmb_quick(device_t dev, u_char slave, int how) +{ + device_t parent = device_get_parent(dev); + int error; + + switch (how) { + case SMB_QWRITE: + error = iicbus_start(parent, slave & ~LSB, IICBUS_TIMEOUT); + break; + + case SMB_QREAD: + error = iicbus_start(parent, slave | LSB, IICBUS_TIMEOUT); + break; + + default: + error = EINVAL; + break; + } + + if (!error) + error = iicbus_stop(parent); + + return (error); +} + +static int +iicsmb_sendb(device_t dev, u_char slave, char byte) +{ + device_t parent = device_get_parent(dev); + int error, sent; + + error = iicbus_start(parent, slave & ~LSB, IICBUS_TIMEOUT); + + if (!error) { + error = iicbus_write(parent, &byte, 1, &sent, IICBUS_TIMEOUT); + + iicbus_stop(parent); + } + + return (error); +} + +static int +iicsmb_recvb(device_t dev, u_char slave, char *byte) +{ + device_t parent = device_get_parent(dev); + int error, read; + + error = iicbus_start(parent, slave | LSB, 0); + + if (!error) { + error = iicbus_read(parent, byte, 1, &read, IIC_LAST_READ, IICBUS_TIMEOUT); + + iicbus_stop(parent); + } + + return (error); +} + +static int +iicsmb_writeb(device_t dev, u_char slave, char cmd, char byte) +{ + device_t parent = device_get_parent(dev); + int error, sent; + + error = iicbus_start(parent, slave & ~LSB, 0); + + if (!error) { + if (!(error = iicbus_write(parent, &cmd, 1, &sent, IICBUS_TIMEOUT))) + error = iicbus_write(parent, &byte, 1, &sent, IICBUS_TIMEOUT); + + iicbus_stop(parent); + } + + return (error); +} + +static int +iicsmb_writew(device_t dev, u_char slave, char cmd, short word) +{ + device_t parent = device_get_parent(dev); + int error, sent; + + char low = (char)(word & 0xff); + char high = (char)((word & 0xff00) >> 8); + + error = iicbus_start(parent, slave & ~LSB, 0); + + if (!error) { + if (!(error = iicbus_write(parent, &cmd, 1, &sent, IICBUS_TIMEOUT))) + if (!(error = iicbus_write(parent, &low, 1, &sent, IICBUS_TIMEOUT))) + error = iicbus_write(parent, &high, 1, &sent, IICBUS_TIMEOUT); + + iicbus_stop(parent); + } + + return (error); +} + +static int +iicsmb_readb(device_t dev, u_char slave, char cmd, char *byte) +{ + device_t parent = device_get_parent(dev); + int error, sent, read; + + if ((error = iicbus_start(parent, slave & ~LSB, IICBUS_TIMEOUT))) + return (error); + + if ((error = iicbus_write(parent, &cmd, 1, &sent, IICBUS_TIMEOUT))) + goto error; + + if ((error = iicbus_repeated_start(parent, slave | LSB, IICBUS_TIMEOUT))) + goto error; + + if ((error = iicbus_read(parent, byte, 1, &read, IIC_LAST_READ, IICBUS_TIMEOUT))) + goto error; + +error: + iicbus_stop(parent); + return (error); +} + +#define BUF2SHORT(low,high) \ + ((short)(((high) & 0xff) << 8) | (short)((low) & 0xff)) + +static int +iicsmb_readw(device_t dev, u_char slave, char cmd, short *word) +{ + device_t parent = device_get_parent(dev); + int error, sent, read; + char buf[2]; + + if ((error = iicbus_start(parent, slave & ~LSB, IICBUS_TIMEOUT))) + return (error); + + if ((error = iicbus_write(parent, &cmd, 1, &sent, IICBUS_TIMEOUT))) + goto error; + + if ((error = iicbus_repeated_start(parent, slave | LSB, IICBUS_TIMEOUT))) + goto error; + + if ((error = iicbus_read(parent, buf, 2, &read, IIC_LAST_READ, IICBUS_TIMEOUT))) + goto error; + + /* first, receive low, then high byte */ + *word = BUF2SHORT(buf[0], buf[1]); + +error: + iicbus_stop(parent); + return (error); +} + +static int +iicsmb_pcall(device_t dev, u_char slave, char cmd, short sdata, short *rdata) +{ + device_t parent = device_get_parent(dev); + int error, sent, read; + char buf[2]; + + if ((error = iicbus_start(parent, slave & ~LSB, IICBUS_TIMEOUT))) + return (error); + + if ((error = iicbus_write(parent, &cmd, 1, &sent, IICBUS_TIMEOUT))) + goto error; + + /* first, send low, then high byte */ + buf[0] = (char)(sdata & 0xff); + buf[1] = (char)((sdata & 0xff00) >> 8); + + if ((error = iicbus_write(parent, buf, 2, &sent, IICBUS_TIMEOUT))) + goto error; + + if ((error = iicbus_repeated_start(parent, slave | LSB, IICBUS_TIMEOUT))) + goto error; + + if ((error = iicbus_read(parent, buf, 2, &read, IIC_LAST_READ, IICBUS_TIMEOUT))) + goto error; + + /* first, receive low, then high byte */ + *rdata = BUF2SHORT(buf[0], buf[1]); + +error: + iicbus_stop(parent); + return (error); +} + +static int +iicsmb_bwrite(device_t dev, u_char slave, char cmd, u_char count, char *buf) +{ + device_t parent = device_get_parent(dev); + int error, sent; + + if ((error = iicbus_start(parent, slave & ~LSB, IICBUS_TIMEOUT))) + goto error; + + if ((error = iicbus_write(parent, &cmd, 1, &sent, IICBUS_TIMEOUT))) + goto error; + + if ((error = iicbus_write(parent, buf, (int)count, &sent, IICBUS_TIMEOUT))) + goto error; + + if ((error = iicbus_stop(parent))) + goto error; + +error: + return (error); +} + +static int +iicsmb_bread(device_t dev, u_char slave, char cmd, u_char count, char *buf) +{ + device_t parent = device_get_parent(dev); + int error, sent, read; + + if ((error = iicbus_start(parent, slave & ~LSB, IICBUS_TIMEOUT))) + return (error); + + if ((error = iicbus_write(parent, &cmd, 1, &sent, IICBUS_TIMEOUT))) + goto error; + + if ((error = iicbus_repeated_start(parent, slave | LSB, IICBUS_TIMEOUT))) + goto error; + + if ((error = iicbus_read(parent, buf, (int)count, &read, + IIC_LAST_READ, IICBUS_TIMEOUT))) + goto error; + +error: + iicbus_stop(parent); + return (error); +} + +DRIVER_MODULE(iicsmb, iicbus, iicsmb_driver, iicsmb_devclass, 0, 0); +MODULE_DEPEND(iicsmb, iicbus, IICBUS_MINVER, IICBUS_PREFVER, IICBUS_MAXVER); +MODULE_DEPEND(iicsmb, smbus, SMBUS_MINVER, SMBUS_PREFVER, SMBUS_MAXVER); +MODULE_VERSION(iicsmb, 1); |
