263 lines
7.0 KiB
C
263 lines
7.0 KiB
C
/* $NetBSD: nslu2_iic.c,v 1.9 2016/02/14 19:54:20 chs 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 <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/kernel.h>
|
|
#include <sys/device.h>
|
|
#include <sys/mutex.h>
|
|
#include <sys/bus.h>
|
|
|
|
#include <dev/i2c/i2cvar.h>
|
|
#include <dev/i2c/i2c_bitbang.h>
|
|
|
|
#include <arm/xscale/ixp425reg.h>
|
|
#include <arm/xscale/ixp425var.h>
|
|
|
|
#include <evbarm/nslu2/nslu2reg.h>
|
|
|
|
struct slugiic_softc {
|
|
struct i2c_controller sc_ic;
|
|
struct i2c_bitbang_ops sc_ibo;
|
|
kmutex_t sc_lock;
|
|
uint32_t sc_dirout;
|
|
};
|
|
|
|
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)
|
|
{
|
|
struct slugiic_softc *sc = arg;
|
|
uint32_t reg;
|
|
int s;
|
|
|
|
if (sc->sc_dirout == bits)
|
|
return;
|
|
|
|
s = splhigh();
|
|
|
|
sc->sc_dirout = bits;
|
|
|
|
if (sc->sc_dirout) {
|
|
/* SDA is output; enable SDA output if SDA OUTR is low */
|
|
reg = GPIO_CONF_READ_4(ixp425_softc, IXP425_GPIO_GPOUTR);
|
|
if ((reg & GPIO_I2C_SDA_BIT) == 0) {
|
|
reg = GPIO_CONF_READ_4(ixp425_softc, IXP425_GPIO_GPOER);
|
|
reg &= ~GPIO_I2C_SDA_BIT;
|
|
GPIO_CONF_WRITE_4(ixp425_softc, IXP425_GPIO_GPOER, reg);
|
|
}
|
|
} else {
|
|
/* SDA is input; disable SDA output */
|
|
reg = GPIO_CONF_READ_4(ixp425_softc, IXP425_GPIO_GPOER);
|
|
reg |= GPIO_I2C_SDA_BIT;
|
|
GPIO_CONF_WRITE_4(ixp425_softc, IXP425_GPIO_GPOER, reg);
|
|
}
|
|
|
|
splx(s);
|
|
}
|
|
|
|
static void
|
|
slugiic_set_bits(void *arg, uint32_t bits)
|
|
{
|
|
struct slugiic_softc *sc = arg;
|
|
uint32_t oer, outr;
|
|
int s;
|
|
|
|
s = splhigh();
|
|
|
|
/*
|
|
* Enable SCL output if the SCL line is to be driven low.
|
|
* Enable SDA output if the SDA line is to be driven low and
|
|
* SDA direction is output.
|
|
* Otherwise switch them to input even if directions are output
|
|
* so that we can emulate open collector output with the pullup
|
|
* resistors.
|
|
* If lines are to be set to high, disable OER first then set OUTR.
|
|
* If lines are to be set to low, set OUTR first then enable OER.
|
|
*/
|
|
oer = GPIO_CONF_READ_4(ixp425_softc, IXP425_GPIO_GPOER);
|
|
if ((bits & GPIO_I2C_SCL_BIT) != 0)
|
|
oer |= GPIO_I2C_SCL_BIT;
|
|
if ((bits & GPIO_I2C_SDA_BIT) != 0)
|
|
oer |= GPIO_I2C_SDA_BIT;
|
|
GPIO_CONF_WRITE_4(ixp425_softc, IXP425_GPIO_GPOER, oer);
|
|
|
|
outr = GPIO_CONF_READ_4(ixp425_softc, IXP425_GPIO_GPOUTR);
|
|
outr &= ~(GPIO_I2C_SDA_BIT | GPIO_I2C_SCL_BIT);
|
|
GPIO_CONF_WRITE_4(ixp425_softc, IXP425_GPIO_GPOUTR, outr | bits);
|
|
|
|
if ((bits & GPIO_I2C_SCL_BIT) == 0)
|
|
oer &= ~GPIO_I2C_SCL_BIT;
|
|
if ((bits & GPIO_I2C_SDA_BIT) == 0 && sc->sc_dirout)
|
|
oer &= ~GPIO_I2C_SDA_BIT;
|
|
GPIO_CONF_WRITE_4(ixp425_softc, IXP425_GPIO_GPOER, oer);
|
|
|
|
splx(s);
|
|
}
|
|
|
|
static uint32_t
|
|
slugiic_read_bits(void *arg)
|
|
{
|
|
uint32_t reg;
|
|
|
|
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(device_t self)
|
|
{
|
|
struct slugiic_softc *sc = device_private(self);
|
|
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);
|
|
|
|
memset(&iba, 0, sizeof(iba));
|
|
iba.iba_tag = &sc->sc_ic;
|
|
(void) config_found_ia(self, "i2cbus", &iba, iicbus_print);
|
|
}
|
|
|
|
static int
|
|
slugiic_match(device_t parent, cfdata_t cf, void *aux)
|
|
{
|
|
|
|
return (1);
|
|
}
|
|
|
|
static void
|
|
slugiic_attach(device_t parent, device_t self, void *aux)
|
|
{
|
|
struct slugiic_softc *sc = device_private(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);
|
|
|
|
sc->sc_dirout = 0;
|
|
|
|
/*
|
|
* Defer until ixp425_softc has been initialised
|
|
*/
|
|
config_interrupts(self, slugiic_deferred_attach);
|
|
}
|
|
|
|
CFATTACH_DECL_NEW(slugiic, sizeof(struct slugiic_softc),
|
|
slugiic_match, slugiic_attach, NULL, NULL);
|