freebsd-nq/sys/arm/xscale/ixp425/cambria_gpio.c
Pedro F. Giffuni 255eff3b0d sys/arm: Minor spelling fixes.
Only affects comments: no functional change.
2016-05-04 15:48:59 +00:00

504 lines
12 KiB
C

/*-
* Copyright (c) 2010, Andrew Thompson <thompsa@FreeBSD.org>
* 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 unmodified, 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.
*/
/*
* GPIO driver for Gateworks Cambria
*
* Note:
* The Cambria PLD does not set the i2c ack bit after each write, if we used the
* regular iicbus interface it would abort the xfer after the address byte
* times out and not write our latch. To get around this we grab the iicbus and
* then do our own bit banging. This is a compromise to changing all the iicbb
* device methods to allow a flag to be passed down and is similir to how Linux
* does it.
*
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/rman.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/gpio.h>
#include <arm/xscale/ixp425/ixp425reg.h>
#include <arm/xscale/ixp425/ixp425var.h>
#include <arm/xscale/ixp425/ixdp425reg.h>
#include <dev/gpio/gpiobusvar.h>
#include <dev/iicbus/iiconf.h>
#include <dev/iicbus/iicbus.h>
#include "iicbb_if.h"
#include "gpio_if.h"
#define IIC_M_WR 0 /* write operation */
#define PLD_ADDR 0xac /* slave address */
#define I2C_DELAY 10
#define GPIO_CONF_CLR(sc, reg, mask) \
GPIO_CONF_WRITE_4(sc, reg, GPIO_CONF_READ_4(sc, reg) &~ (mask))
#define GPIO_CONF_SET(sc, reg, mask) \
GPIO_CONF_WRITE_4(sc, reg, GPIO_CONF_READ_4(sc, reg) | (mask))
#define GPIO_LOCK(_sc) mtx_lock(&(_sc)->sc_mtx)
#define GPIO_UNLOCK(_sc) mtx_unlock(&(_sc)->sc_mtx)
#define GPIO_LOCK_ASSERT(_sc) mtx_assert(&(_sc)->sc_mtx, MA_OWNED)
#define GPIO_PINS 5
struct cambria_gpio_softc {
device_t sc_dev;
device_t sc_busdev;
bus_space_tag_t sc_iot;
bus_space_handle_t sc_gpio_ioh;
struct mtx sc_mtx;
struct gpio_pin sc_pins[GPIO_PINS];
uint8_t sc_latch;
uint8_t sc_val;
};
struct cambria_gpio_pin {
const char *name;
int pin;
int flags;
};
extern struct ixp425_softc *ixp425_softc;
static struct cambria_gpio_pin cambria_gpio_pins[GPIO_PINS] = {
{ "PLD0", 0, GPIO_PIN_OUTPUT },
{ "PLD1", 1, GPIO_PIN_OUTPUT },
{ "PLD2", 2, GPIO_PIN_OUTPUT },
{ "PLD3", 3, GPIO_PIN_OUTPUT },
{ "PLD4", 4, GPIO_PIN_OUTPUT },
};
/*
* Helpers
*/
static int cambria_gpio_read(struct cambria_gpio_softc *, uint32_t, unsigned int *);
static int cambria_gpio_write(struct cambria_gpio_softc *);
/*
* Driver stuff
*/
static int cambria_gpio_probe(device_t dev);
static int cambria_gpio_attach(device_t dev);
static int cambria_gpio_detach(device_t dev);
/*
* GPIO interface
*/
static device_t cambria_gpio_get_bus(device_t);
static int cambria_gpio_pin_max(device_t dev, int *maxpin);
static int cambria_gpio_pin_getcaps(device_t dev, uint32_t pin, uint32_t *caps);
static int cambria_gpio_pin_getflags(device_t dev, uint32_t pin, uint32_t
*flags);
static int cambria_gpio_pin_getname(device_t dev, uint32_t pin, char *name);
static int cambria_gpio_pin_setflags(device_t dev, uint32_t pin, uint32_t flags);
static int cambria_gpio_pin_set(device_t dev, uint32_t pin, unsigned int value);
static int cambria_gpio_pin_get(device_t dev, uint32_t pin, unsigned int *val);
static int cambria_gpio_pin_toggle(device_t dev, uint32_t pin);
static int
i2c_getsda(struct cambria_gpio_softc *sc)
{
uint32_t reg;
IXP4XX_GPIO_LOCK();
GPIO_CONF_SET(sc, IXP425_GPIO_GPOER, GPIO_I2C_SDA_BIT);
reg = GPIO_CONF_READ_4(sc, IXP425_GPIO_GPINR);
IXP4XX_GPIO_UNLOCK();
return (reg & GPIO_I2C_SDA_BIT);
}
static void
i2c_setsda(struct cambria_gpio_softc *sc, int val)
{
IXP4XX_GPIO_LOCK();
GPIO_CONF_CLR(sc, IXP425_GPIO_GPOUTR, GPIO_I2C_SDA_BIT);
if (val)
GPIO_CONF_SET(sc, IXP425_GPIO_GPOER, GPIO_I2C_SDA_BIT);
else
GPIO_CONF_CLR(sc, IXP425_GPIO_GPOER, GPIO_I2C_SDA_BIT);
IXP4XX_GPIO_UNLOCK();
DELAY(I2C_DELAY);
}
static void
i2c_setscl(struct cambria_gpio_softc *sc, int val)
{
IXP4XX_GPIO_LOCK();
GPIO_CONF_CLR(sc, IXP425_GPIO_GPOUTR, GPIO_I2C_SCL_BIT);
if (val)
GPIO_CONF_SET(sc, IXP425_GPIO_GPOER, GPIO_I2C_SCL_BIT);
else
GPIO_CONF_CLR(sc, IXP425_GPIO_GPOER, GPIO_I2C_SCL_BIT);
IXP4XX_GPIO_UNLOCK();
DELAY(I2C_DELAY);
}
static void
i2c_sendstart(struct cambria_gpio_softc *sc)
{
i2c_setsda(sc, 1);
i2c_setscl(sc, 1);
i2c_setsda(sc, 0);
i2c_setscl(sc, 0);
}
static void
i2c_sendstop(struct cambria_gpio_softc *sc)
{
i2c_setscl(sc, 1);
i2c_setsda(sc, 1);
i2c_setscl(sc, 0);
i2c_setsda(sc, 0);
}
static void
i2c_sendbyte(struct cambria_gpio_softc *sc, u_char data)
{
int i;
for (i=7; i>=0; i--) {
i2c_setsda(sc, data & (1<<i));
i2c_setscl(sc, 1);
i2c_setscl(sc, 0);
}
i2c_setscl(sc, 1);
i2c_getsda(sc);
i2c_setscl(sc, 0);
}
static u_char
i2c_readbyte(struct cambria_gpio_softc *sc)
{
int i;
unsigned char data=0;
for (i=7; i>=0; i--)
{
i2c_setscl(sc, 1);
if (i2c_getsda(sc))
data |= (1<<i);
i2c_setscl(sc, 0);
}
return data;
}
static int
cambria_gpio_read(struct cambria_gpio_softc *sc, uint32_t pin, unsigned int *val)
{
device_t dev = sc->sc_dev;
int error;
error = iicbus_request_bus(device_get_parent(dev), dev,
IIC_DONTWAIT);
if (error)
return (error);
i2c_sendstart(sc);
i2c_sendbyte(sc, PLD_ADDR | LSB);
*val = (i2c_readbyte(sc) & (1 << pin)) != 0;
i2c_sendstop(sc);
iicbus_release_bus(device_get_parent(dev), dev);
return (0);
}
static int
cambria_gpio_write(struct cambria_gpio_softc *sc)
{
device_t dev = sc->sc_dev;
int error;
error = iicbus_request_bus(device_get_parent(dev), dev,
IIC_DONTWAIT);
if (error)
return (error);
i2c_sendstart(sc);
i2c_sendbyte(sc, PLD_ADDR & ~LSB);
i2c_sendbyte(sc, sc->sc_latch);
i2c_sendstop(sc);
iicbus_release_bus(device_get_parent(dev), dev);
return (0);
}
static device_t
cambria_gpio_get_bus(device_t dev)
{
struct cambria_gpio_softc *sc;
sc = device_get_softc(dev);
return (sc->sc_busdev);
}
static int
cambria_gpio_pin_max(device_t dev, int *maxpin)
{
*maxpin = GPIO_PINS - 1;
return (0);
}
static int
cambria_gpio_pin_getcaps(device_t dev, uint32_t pin, uint32_t *caps)
{
struct cambria_gpio_softc *sc = device_get_softc(dev);
if (pin >= GPIO_PINS)
return (EINVAL);
*caps = sc->sc_pins[pin].gp_caps;
return (0);
}
static int
cambria_gpio_pin_getflags(device_t dev, uint32_t pin, uint32_t *flags)
{
struct cambria_gpio_softc *sc = device_get_softc(dev);
if (pin >= GPIO_PINS)
return (EINVAL);
*flags = sc->sc_pins[pin].gp_flags;
return (0);
}
static int
cambria_gpio_pin_getname(device_t dev, uint32_t pin, char *name)
{
struct cambria_gpio_softc *sc = device_get_softc(dev);
if (pin >= GPIO_PINS)
return (EINVAL);
memcpy(name, sc->sc_pins[pin].gp_name, GPIOMAXNAME);
return (0);
}
static int
cambria_gpio_pin_setflags(device_t dev, uint32_t pin, uint32_t flags)
{
struct cambria_gpio_softc *sc = device_get_softc(dev);
int error;
uint8_t mask;
mask = 1 << pin;
if (pin >= GPIO_PINS)
return (EINVAL);
GPIO_LOCK(sc);
sc->sc_pins[pin].gp_flags = flags;
/*
* Writing a logical one sets the signal high and writing a logical
* zero sets the signal low. To configure a digital I/O signal as an
* input, a logical one must first be written to the data bit to
* three-state the associated output.
*/
if (flags & GPIO_PIN_INPUT || sc->sc_val & mask)
sc->sc_latch |= mask; /* input or output & high */
else
sc->sc_latch &= ~mask;
error = cambria_gpio_write(sc);
GPIO_UNLOCK(sc);
return (error);
}
static int
cambria_gpio_pin_set(device_t dev, uint32_t pin, unsigned int value)
{
struct cambria_gpio_softc *sc = device_get_softc(dev);
int error;
uint8_t mask;
mask = 1 << pin;
if (pin >= GPIO_PINS)
return (EINVAL);
GPIO_LOCK(sc);
if (value)
sc->sc_val |= mask;
else
sc->sc_val &= ~mask;
if (sc->sc_pins[pin].gp_flags != GPIO_PIN_OUTPUT) {
/* just save, altering the latch will disable input */
GPIO_UNLOCK(sc);
return (0);
}
if (value)
sc->sc_latch |= mask;
else
sc->sc_latch &= ~mask;
error = cambria_gpio_write(sc);
GPIO_UNLOCK(sc);
return (error);
}
static int
cambria_gpio_pin_get(device_t dev, uint32_t pin, unsigned int *val)
{
struct cambria_gpio_softc *sc = device_get_softc(dev);
int error = 0;
if (pin >= GPIO_PINS)
return (EINVAL);
GPIO_LOCK(sc);
if (sc->sc_pins[pin].gp_flags == GPIO_PIN_OUTPUT)
*val = (sc->sc_latch & (1 << pin)) ? 1 : 0;
else
error = cambria_gpio_read(sc, pin, val);
GPIO_UNLOCK(sc);
return (error);
}
static int
cambria_gpio_pin_toggle(device_t dev, uint32_t pin)
{
struct cambria_gpio_softc *sc = device_get_softc(dev);
int error = 0;
if (pin >= GPIO_PINS)
return (EINVAL);
GPIO_LOCK(sc);
sc->sc_val ^= (1 << pin);
if (sc->sc_pins[pin].gp_flags == GPIO_PIN_OUTPUT) {
sc->sc_latch ^= (1 << pin);
error = cambria_gpio_write(sc);
}
GPIO_UNLOCK(sc);
return (error);
}
static int
cambria_gpio_probe(device_t dev)
{
device_set_desc(dev, "Gateworks Cambria GPIO driver");
return (0);
}
static int
cambria_gpio_attach(device_t dev)
{
struct cambria_gpio_softc *sc = device_get_softc(dev);
int pin;
sc->sc_dev = dev;
sc->sc_iot = ixp425_softc->sc_iot;
sc->sc_gpio_ioh = ixp425_softc->sc_gpio_ioh;
mtx_init(&sc->sc_mtx, device_get_nameunit(dev), NULL, MTX_DEF);
for (pin = 0; pin < GPIO_PINS; pin++) {
struct cambria_gpio_pin *p = &cambria_gpio_pins[pin];
strncpy(sc->sc_pins[pin].gp_name, p->name, GPIOMAXNAME);
sc->sc_pins[pin].gp_pin = pin;
sc->sc_pins[pin].gp_caps = GPIO_PIN_INPUT|GPIO_PIN_OUTPUT;
sc->sc_pins[pin].gp_flags = 0;
cambria_gpio_pin_setflags(dev, pin, p->flags);
}
sc->sc_busdev = gpiobus_attach_bus(dev);
if (sc->sc_busdev == NULL) {
mtx_destroy(&sc->sc_mtx);
return (ENXIO);
}
return (0);
}
static int
cambria_gpio_detach(device_t dev)
{
struct cambria_gpio_softc *sc = device_get_softc(dev);
KASSERT(mtx_initialized(&sc->sc_mtx), ("gpio mutex not initialized"));
gpiobus_detach_bus(dev);
mtx_destroy(&sc->sc_mtx);
return(0);
}
static device_method_t cambria_gpio_methods[] = {
DEVMETHOD(device_probe, cambria_gpio_probe),
DEVMETHOD(device_attach, cambria_gpio_attach),
DEVMETHOD(device_detach, cambria_gpio_detach),
/* GPIO protocol */
DEVMETHOD(gpio_get_bus, cambria_gpio_get_bus),
DEVMETHOD(gpio_pin_max, cambria_gpio_pin_max),
DEVMETHOD(gpio_pin_getname, cambria_gpio_pin_getname),
DEVMETHOD(gpio_pin_getflags, cambria_gpio_pin_getflags),
DEVMETHOD(gpio_pin_getcaps, cambria_gpio_pin_getcaps),
DEVMETHOD(gpio_pin_setflags, cambria_gpio_pin_setflags),
DEVMETHOD(gpio_pin_get, cambria_gpio_pin_get),
DEVMETHOD(gpio_pin_set, cambria_gpio_pin_set),
DEVMETHOD(gpio_pin_toggle, cambria_gpio_pin_toggle),
{0, 0},
};
static driver_t cambria_gpio_driver = {
"gpio",
cambria_gpio_methods,
sizeof(struct cambria_gpio_softc),
};
static devclass_t cambria_gpio_devclass;
DRIVER_MODULE(gpio_cambria, iicbus, cambria_gpio_driver, cambria_gpio_devclass, 0, 0);
MODULE_VERSION(gpio_cambria, 1);
MODULE_DEPEND(gpio_cambria, iicbus, 1, 1, 1);