freebsd-skq/sys/dev/iicbus/iicsmb.c
Pedro F. Giffuni 718cf2ccb9 sys/dev: further adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
2017-11-27 14:52:40 +00:00

483 lines
11 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* I2C to SMB bridge
*
* Example:
*
* smb bttv
* \ /
* smbus
* / \
* iicsmb bti2c
* |
* iicbus
* / | \
* iicbb pcf ...
* |
* lpbb
*/
#include <sys/param.h>
#include <sys/bus.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/module.h>
#include <sys/mutex.h>
#include <sys/systm.h>
#include <sys/uio.h>
#include <dev/iicbus/iiconf.h>
#include <dev/iicbus/iicbus.h>
#include <dev/smbus/smb.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 */
struct mtx lock;
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 int iicsmb_intr(device_t dev, int event, char *buf);
static int iicsmb_callback(device_t dev, int index, void *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),
/* 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),
DEVMETHOD_END
};
static driver_t iicsmb_driver = {
"iicsmb",
iicsmb_methods,
sizeof(struct iicsmb_softc),
};
static void
iicsmb_identify(driver_t *driver, device_t parent)
{
if (device_find_child(parent, "iicsmb", -1) == NULL)
BUS_ADD_CHILD(parent, 0, "iicsmb", -1);
}
static int
iicsmb_probe(device_t dev)
{
device_set_desc(dev, "SMBus over I2C bridge");
return (BUS_PROBE_NOWILDCARD);
}
static int
iicsmb_attach(device_t dev)
{
struct iicsmb_softc *sc = (struct iicsmb_softc *)device_get_softc(dev);
mtx_init(&sc->lock, "iicsmb", NULL, MTX_DEF);
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);
device_delete_children(dev);
mtx_destroy(&sc->lock);
return (0);
}
/*
* iicsmb_intr()
*
* iicbus interrupt handler
*/
static int
iicsmb_intr(device_t dev, int event, char *buf)
{
struct iicsmb_softc *sc = (struct iicsmb_softc *)device_get_softc(dev);
mtx_lock(&sc->lock);
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);
}
mtx_unlock(&sc->lock);
return (0);
}
static int
iicsmb_callback(device_t dev, int index, void *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
iic2smb_error(int error)
{
switch (error) {
case IIC_NOERR:
return (SMB_ENOERR);
case IIC_EBUSERR:
return (SMB_EBUSERR);
case IIC_ENOACK:
return (SMB_ENOACK);
case IIC_ETIMEOUT:
return (SMB_ETIMEOUT);
case IIC_EBUSBSY:
return (SMB_EBUSY);
case IIC_ESTATUS:
return (SMB_EBUSERR);
case IIC_EUNDERFLOW:
return (SMB_EBUSERR);
case IIC_EOVERFLOW:
return (SMB_EBUSERR);
case IIC_ENOTSUPP:
return (SMB_ENOTSUPP);
case IIC_ENOADDR:
return (SMB_EBUSERR);
case IIC_ERESOURCE:
return (SMB_EBUSERR);
default:
return (SMB_EBUSERR);
}
}
#define TRANSFER_MSGS(dev, msgs) iicbus_transfer(dev, msgs, nitems(msgs))
static int
iicsmb_quick(device_t dev, u_char slave, int how)
{
struct iic_msg msgs[] = {
{ slave, how == SMB_QWRITE ? IIC_M_WR : IIC_M_RD, 0, NULL },
};
int error;
switch (how) {
case SMB_QWRITE:
case SMB_QREAD:
break;
default:
return (SMB_EINVAL);
}
error = TRANSFER_MSGS(dev, msgs);
return (iic2smb_error(error));
}
static int
iicsmb_sendb(device_t dev, u_char slave, char byte)
{
struct iic_msg msgs[] = {
{ slave, IIC_M_WR, 1, &byte },
};
int error;
error = TRANSFER_MSGS(dev, msgs);
return (iic2smb_error(error));
}
static int
iicsmb_recvb(device_t dev, u_char slave, char *byte)
{
struct iic_msg msgs[] = {
{ slave, IIC_M_RD, 1, byte },
};
int error;
error = TRANSFER_MSGS(dev, msgs);
return (iic2smb_error(error));
}
static int
iicsmb_writeb(device_t dev, u_char slave, char cmd, char byte)
{
uint8_t bytes[] = { cmd, byte };
struct iic_msg msgs[] = {
{ slave, IIC_M_WR, nitems(bytes), bytes },
};
int error;
error = TRANSFER_MSGS(dev, msgs);
return (iic2smb_error(error));
}
static int
iicsmb_writew(device_t dev, u_char slave, char cmd, short word)
{
uint8_t bytes[] = { cmd, word & 0xff, word >> 8 };
struct iic_msg msgs[] = {
{ slave, IIC_M_WR, nitems(bytes), bytes },
};
int error;
error = TRANSFER_MSGS(dev, msgs);
return (iic2smb_error(error));
}
static int
iicsmb_readb(device_t dev, u_char slave, char cmd, char *byte)
{
struct iic_msg msgs[] = {
{ slave, IIC_M_WR | IIC_M_NOSTOP, 1, &cmd },
{ slave, IIC_M_RD, 1, byte },
};
int error;
error = TRANSFER_MSGS(dev, msgs);
return (iic2smb_error(error));
}
static int
iicsmb_readw(device_t dev, u_char slave, char cmd, short *word)
{
uint8_t buf[2];
struct iic_msg msgs[] = {
{ slave, IIC_M_WR | IIC_M_NOSTOP, 1, &cmd },
{ slave, IIC_M_RD, nitems(buf), buf },
};
int error;
error = TRANSFER_MSGS(dev, msgs);
if (error == 0)
*word = ((uint16_t)buf[1] << 8) | buf[0];
return (iic2smb_error(error));
}
static int
iicsmb_pcall(device_t dev, u_char slave, char cmd, short sdata, short *rdata)
{
uint8_t in[3] = { cmd, sdata & 0xff, sdata >> 8 };
uint8_t out[2];
struct iic_msg msgs[] = {
{ slave, IIC_M_WR | IIC_M_NOSTOP, nitems(in), in },
{ slave, IIC_M_RD, nitems(out), out },
};
int error;
error = TRANSFER_MSGS(dev, msgs);
if (error == 0)
*rdata = ((uint16_t)out[1] << 8) | out[0];
return (iic2smb_error(error));
}
static int
iicsmb_bwrite(device_t dev, u_char slave, char cmd, u_char count, char *buf)
{
uint8_t bytes[2] = { cmd, count };
struct iic_msg msgs[] = {
{ slave, IIC_M_WR | IIC_M_NOSTOP, nitems(bytes), bytes },
{ slave, IIC_M_WR | IIC_M_NOSTART, count, buf },
};
int error;
if (count > SMB_MAXBLOCKSIZE || count == 0)
return (SMB_EINVAL);
error = TRANSFER_MSGS(dev, msgs);
return (iic2smb_error(error));
}
static int
iicsmb_bread(device_t dev, u_char slave, char cmd, u_char *count, char *buf)
{
struct iic_msg msgs[] = {
{ slave, IIC_M_WR | IIC_M_NOSTOP, 1, &cmd },
{ slave, IIC_M_RD | IIC_M_NOSTOP, 1, count },
};
struct iic_msg block_msg[] = {
{ slave, IIC_M_RD | IIC_M_NOSTART, 0, buf },
};
device_t parent = device_get_parent(dev);
int error;
/* Have to do this because the command is split in two transfers. */
error = iicbus_request_bus(parent, dev, IIC_WAIT);
if (error == 0)
error = TRANSFER_MSGS(dev, msgs);
if (error == 0) {
/*
* If the slave offers an empty or a too long reply,
* read one byte to generate the stop or abort.
*/
if (*count > SMB_MAXBLOCKSIZE || *count == 0)
block_msg[0].len = 1;
else
block_msg[0].len = *count;
error = TRANSFER_MSGS(dev, block_msg);
if (*count > SMB_MAXBLOCKSIZE || *count == 0)
error = SMB_EINVAL;
}
(void)iicbus_release_bus(parent, dev);
return (iic2smb_error(error));
}
DRIVER_MODULE(iicsmb, iicbus, iicsmb_driver, iicsmb_devclass, 0, 0);
DRIVER_MODULE(smbus, iicsmb, smbus_driver, smbus_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);