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freebsd-dev/sys/powerpc/powermac/kiic.c
Nathan Whitehorn 509142e189 Where appropriate, use the endian-flipping OF_getencprop() instead of 
OF_getprop() to get encode-int encoded values from the OF tree. This is
a no-op at present, since all existing PowerPC ports are big-endian, but
it is a correctness improvement and will be required if we have a
little-endian kernel at some future point.

Where it is totally impossible for the code ever to be used on a
little-endian system (much of powerpc/powermac, for instance), I have not
necessarily made the appropriate changes.

MFC after:	1 month
2015-11-17 16:07:43 +00:00

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/*-
* Copyright (c) 2001 Tsubai Masanari. 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. 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.
*
* $FreeBSD$
* NetBSD: ki2c.c,v 1.11 2007/12/06 17:00:33 ad Exp
* Id: ki2c.c,v 1.7 2002/10/05 09:56:05 tsubai Exp
*/
/*
* Support routines for the Keywest I2C controller.
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/bus.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <machine/resource.h>
#include <machine/bus.h>
#include <sys/rman.h>
#include <dev/iicbus/iicbus.h>
#include <dev/iicbus/iiconf.h>
#include <dev/ofw/ofw_bus.h>
#include "iicbus_if.h"
/* Keywest I2C Register offsets */
#define MODE 0
#define CONTROL 1
#define STATUS 2
#define ISR 3
#define IER 4
#define ADDR 5
#define SUBADDR 6
#define DATA 7
#define REV 8
/* MODE */
#define I2C_SPEED 0x03 /* Speed mask */
#define I2C_100kHz 0x00
#define I2C_50kHz 0x01
#define I2C_25kHz 0x02
#define I2C_MODE 0x0c /* Mode mask */
#define I2C_DUMBMODE 0x00 /* Dumb mode */
#define I2C_STDMODE 0x04 /* Standard mode */
#define I2C_STDSUBMODE 0x08 /* Standard mode + sub address */
#define I2C_COMBMODE 0x0c /* Combined mode */
#define I2C_PORT 0xf0 /* Port mask */
/* CONTROL */
#define I2C_CT_AAK 0x01 /* Send AAK */
#define I2C_CT_ADDR 0x02 /* Send address(es) */
#define I2C_CT_STOP 0x04 /* Send STOP */
#define I2C_CT_START 0x08 /* Send START */
/* STATUS */
#define I2C_ST_BUSY 0x01 /* Busy */
#define I2C_ST_LASTAAK 0x02 /* Last AAK */
#define I2C_ST_LASTRW 0x04 /* Last R/W */
#define I2C_ST_SDA 0x08 /* SDA */
#define I2C_ST_SCL 0x10 /* SCL */
/* ISR/IER */
#define I2C_INT_DATA 0x01 /* Data byte sent/received */
#define I2C_INT_ADDR 0x02 /* Address sent */
#define I2C_INT_STOP 0x04 /* STOP condition sent */
#define I2C_INT_START 0x08 /* START condition sent */
/* I2C flags */
#define I2C_BUSY 0x01
#define I2C_READING 0x02
#define I2C_ERROR 0x04
#define I2C_SELECTED 0x08
struct kiic_softc {
device_t sc_dev;
phandle_t sc_node;
struct mtx sc_mutex;
struct resource *sc_reg;
int sc_irqrid;
struct resource *sc_irq;
void *sc_ih;
u_int sc_regstep;
u_int sc_flags;
u_char *sc_data;
int sc_resid;
uint16_t sc_i2c_base;
device_t sc_iicbus;
};
static int kiic_probe(device_t dev);
static int kiic_attach(device_t dev);
static void kiic_writereg(struct kiic_softc *sc, u_int, u_int);
static u_int kiic_readreg(struct kiic_softc *, u_int);
static void kiic_setport(struct kiic_softc *, u_int);
static void kiic_setmode(struct kiic_softc *, u_int);
static void kiic_setspeed(struct kiic_softc *, u_int);
static void kiic_intr(void *xsc);
static int kiic_transfer(device_t dev, struct iic_msg *msgs,
uint32_t nmsgs);
static phandle_t kiic_get_node(device_t bus, device_t dev);
static device_method_t kiic_methods[] = {
/* device interface */
DEVMETHOD(device_probe, kiic_probe),
DEVMETHOD(device_attach, kiic_attach),
/* iicbus interface */
DEVMETHOD(iicbus_callback, iicbus_null_callback),
DEVMETHOD(iicbus_transfer, kiic_transfer),
/* ofw_bus interface */
DEVMETHOD(ofw_bus_get_node, kiic_get_node),
{ 0, 0 }
};
static driver_t kiic_driver = {
"iichb",
kiic_methods,
sizeof(struct kiic_softc)
};
static devclass_t kiic_devclass;
DRIVER_MODULE(kiic, macio, kiic_driver, kiic_devclass, 0, 0);
DRIVER_MODULE(kiic, unin, kiic_driver, kiic_devclass, 0, 0);
static int
kiic_probe(device_t self)
{
const char *name;
name = ofw_bus_get_name(self);
if (name && strcmp(name, "i2c") == 0) {
device_set_desc(self, "Keywest I2C controller");
return (0);
}
return (ENXIO);
}
static int
kiic_attach(device_t self)
{
struct kiic_softc *sc = device_get_softc(self);
int rid, rate;
phandle_t node;
char name[64];
bzero(sc, sizeof(*sc));
sc->sc_dev = self;
node = ofw_bus_get_node(self);
if (node == 0 || node == -1) {
return (EINVAL);
}
rid = 0;
sc->sc_reg = bus_alloc_resource_any(self, SYS_RES_MEMORY,
&rid, RF_ACTIVE);
if (sc->sc_reg == NULL) {
return (ENOMEM);
}
if (OF_getencprop(node, "AAPL,i2c-rate", &rate, 4) != 4) {
device_printf(self, "cannot get i2c-rate\n");
return (ENXIO);
}
if (OF_getencprop(node, "AAPL,address-step", &sc->sc_regstep, 4) != 4) {
device_printf(self, "unable to find i2c address step\n");
return (ENXIO);
}
/*
* Some Keywest I2C devices have their children attached directly
* underneath them. Some have a single 'iicbus' child with the
* devices underneath that. Sort this out, and make sure that the
* OFW I2C layer has the correct node.
*
* Note: the I2C children of the Uninorth bridges have two ports.
* In general, the port is designated in the 9th bit of the I2C
* address. However, for kiic devices with children attached below
* an i2c-bus node, the port is indicated in the 'reg' property
* of the i2c-bus node.
*/
sc->sc_node = node;
node = OF_child(node);
if (OF_getprop(node, "name", name, sizeof(name)) > 0) {
if (strcmp(name,"i2c-bus") == 0) {
phandle_t reg;
if (OF_getprop(node, "reg", &reg, sizeof(reg)) > 0)
sc->sc_i2c_base = reg << 8;
sc->sc_node = node;
}
}
mtx_init(&sc->sc_mutex, "kiic", NULL, MTX_DEF);
sc->sc_irq = bus_alloc_resource_any(self, SYS_RES_IRQ, &sc->sc_irqrid,
RF_ACTIVE);
bus_setup_intr(self, sc->sc_irq, INTR_TYPE_MISC | INTR_MPSAFE, NULL,
kiic_intr, sc, &sc->sc_ih);
kiic_writereg(sc, ISR, kiic_readreg(sc, ISR));
kiic_writereg(sc, STATUS, 0);
kiic_writereg(sc, IER, 0);
kiic_setmode(sc, I2C_STDMODE);
kiic_setspeed(sc, I2C_100kHz); /* XXX rate */
kiic_writereg(sc, IER, I2C_INT_DATA | I2C_INT_ADDR | I2C_INT_STOP);
if (bootverbose)
device_printf(self, "Revision: %02X\n", kiic_readreg(sc, REV));
/* Add the IIC bus layer */
sc->sc_iicbus = device_add_child(self, "iicbus", -1);
return (bus_generic_attach(self));
}
static void
kiic_writereg(struct kiic_softc *sc, u_int reg, u_int val)
{
bus_write_4(sc->sc_reg, sc->sc_regstep * reg, val);
DELAY(100); /* register access delay */
}
static u_int
kiic_readreg(struct kiic_softc *sc, u_int reg)
{
return bus_read_4(sc->sc_reg, sc->sc_regstep * reg) & 0xff;
}
static void
kiic_setmode(struct kiic_softc *sc, u_int mode)
{
u_int x;
KASSERT((mode & ~I2C_MODE) == 0, ("bad mode"));
x = kiic_readreg(sc, MODE);
x &= ~I2C_MODE;
x |= mode;
kiic_writereg(sc, MODE, x);
}
static void
kiic_setport(struct kiic_softc *sc, u_int port)
{
u_int x;
KASSERT(port == 1 || port == 0, ("bad port"));
x = kiic_readreg(sc, MODE);
x &= ~I2C_PORT;
x |= (port << 4);
kiic_writereg(sc, MODE, x);
}
static void
kiic_setspeed(struct kiic_softc *sc, u_int speed)
{
u_int x;
KASSERT((speed & ~I2C_SPEED) == 0, ("bad speed"));
x = kiic_readreg(sc, MODE);
x &= ~I2C_SPEED;
x |= speed;
kiic_writereg(sc, MODE, x);
}
static void
kiic_intr(void *xsc)
{
struct kiic_softc *sc = xsc;
u_int isr;
uint32_t x;
mtx_lock(&sc->sc_mutex);
isr = kiic_readreg(sc, ISR);
if (isr & I2C_INT_ADDR) {
sc->sc_flags |= I2C_SELECTED;
if (sc->sc_flags & I2C_READING) {
if (sc->sc_resid > 1) {
x = kiic_readreg(sc, CONTROL);
x |= I2C_CT_AAK;
kiic_writereg(sc, CONTROL, x);
}
} else {
kiic_writereg(sc, DATA, *sc->sc_data++);
sc->sc_resid--;
}
}
if (isr & I2C_INT_DATA) {
if (sc->sc_flags & I2C_READING) {
if (sc->sc_resid > 0) {
*sc->sc_data++ = kiic_readreg(sc, DATA);
sc->sc_resid--;
}
if (sc->sc_resid == 0) /* done */
kiic_writereg(sc, CONTROL, 0);
} else {
if (sc->sc_resid == 0) {
x = kiic_readreg(sc, CONTROL);
x |= I2C_CT_STOP;
kiic_writereg(sc, CONTROL, x);
} else {
kiic_writereg(sc, DATA, *sc->sc_data++);
sc->sc_resid--;
}
}
}
if (isr & I2C_INT_STOP) {
kiic_writereg(sc, CONTROL, 0);
sc->sc_flags &= ~I2C_SELECTED;
wakeup(sc->sc_dev);
}
kiic_writereg(sc, ISR, isr);
mtx_unlock(&sc->sc_mutex);
}
static int
kiic_transfer(device_t dev, struct iic_msg *msgs, uint32_t nmsgs)
{
struct kiic_softc *sc;
int i, x, timo, err;
uint16_t addr;
uint8_t subaddr;
sc = device_get_softc(dev);
timo = 100;
subaddr = 0;
mtx_lock(&sc->sc_mutex);
if (sc->sc_flags & I2C_BUSY)
mtx_sleep(dev, &sc->sc_mutex, 0, "kiic", timo);
if (sc->sc_flags & I2C_BUSY) {
mtx_unlock(&sc->sc_mutex);
return (ETIMEDOUT);
}
sc->sc_flags = I2C_BUSY;
/* Clear pending interrupts, and reset controller */
kiic_writereg(sc, ISR, kiic_readreg(sc, ISR));
kiic_writereg(sc, STATUS, 0);
for (i = 0; i < nmsgs; i++) {
if (msgs[i].flags & IIC_M_NOSTOP) {
if (msgs[i+1].flags & IIC_M_RD)
kiic_setmode(sc, I2C_COMBMODE);
else
kiic_setmode(sc, I2C_STDSUBMODE);
KASSERT(msgs[i].len == 1, ("oversize I2C message"));
subaddr = msgs[i].buf[0];
i++;
} else {
kiic_setmode(sc, I2C_STDMODE);
}
sc->sc_data = msgs[i].buf;
sc->sc_resid = msgs[i].len;
sc->sc_flags = I2C_BUSY;
addr = msgs[i].slave;
timo = 1000 + sc->sc_resid * 200;
timo += 100000;
if (msgs[i].flags & IIC_M_RD) {
sc->sc_flags |= I2C_READING;
addr |= 1;
}
addr |= sc->sc_i2c_base;
kiic_setport(sc, (addr & 0x100) >> 8);
kiic_writereg(sc, ADDR, addr & 0xff);
kiic_writereg(sc, SUBADDR, subaddr);
x = kiic_readreg(sc, CONTROL) | I2C_CT_ADDR;
kiic_writereg(sc, CONTROL, x);
err = mtx_sleep(dev, &sc->sc_mutex, 0, "kiic", timo);
msgs[i].len -= sc->sc_resid;
if ((sc->sc_flags & I2C_ERROR) || err == EWOULDBLOCK) {
device_printf(sc->sc_dev, "I2C error\n");
sc->sc_flags = 0;
mtx_unlock(&sc->sc_mutex);
return (EIO);
}
}
sc->sc_flags = 0;
mtx_unlock(&sc->sc_mutex);
return (0);
}
static phandle_t
kiic_get_node(device_t bus, device_t dev)
{
struct kiic_softc *sc;
sc = device_get_softc(bus);
/* We only have one child, the I2C bus, which needs our own node. */
return sc->sc_node;
}
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