freebsd-dev/sys/arm/amlogic/aml8726/aml8726_gpio.c
2016-11-14 11:41:22 +00:00

372 lines
8.8 KiB
C

/*-
* Copyright 2013-2015 John Wehle <john@feith.com>
* 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.
*/
/*
* Amlogic aml8726 GPIO driver.
*
* Note: The OEN register is active * low *. Setting a bit to zero
* enables the output driver, setting a bit to one disables the driver.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/conf.h>
#include <sys/bus.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/resource.h>
#include <sys/rman.h>
#include <sys/gpio.h>
#include <machine/bus.h>
#include <dev/ofw/ofw_bus.h>
#include <dev/ofw/ofw_bus_subr.h>
#include <dev/gpio/gpiobusvar.h>
#include "gpio_if.h"
struct aml8726_gpio_softc {
device_t dev;
struct resource *res[3];
struct mtx mtx;
uint32_t npins;
device_t busdev;
};
static struct resource_spec aml8726_gpio_spec[] = {
{ SYS_RES_MEMORY, 0, RF_ACTIVE | RF_SHAREABLE }, /* oen */
{ SYS_RES_MEMORY, 1, RF_ACTIVE | RF_SHAREABLE }, /* output */
{ SYS_RES_MEMORY, 2, RF_ACTIVE }, /* input */
{ -1, 0 }
};
#define AML_GPIO_LOCK(sc) mtx_lock(&(sc)->mtx)
#define AML_GPIO_UNLOCK(sc) mtx_unlock(&(sc)->mtx)
#define AML_GPIO_LOCK_INIT(sc) \
mtx_init(&(sc)->mtx, device_get_nameunit((sc)->dev), \
"gpio", MTX_DEF)
#define AML_GPIO_LOCK_DESTROY(sc) mtx_destroy(&(sc)->mtx);
#define AML_GPIO_OE_N_REG 0
#define AML_GPIO_OUT_REG 1
#define AML_GPIO_IN_REG 2
#define CSR_WRITE_4(sc, reg, val) bus_write_4((sc)->res[reg], 0, (val))
#define CSR_READ_4(sc, reg) bus_read_4((sc)->res[reg], 0)
static int
aml8726_gpio_probe(device_t dev)
{
if (!ofw_bus_status_okay(dev))
return (ENXIO);
if (!ofw_bus_is_compatible(dev, "amlogic,aml8726-gpio"))
return (ENXIO);
device_set_desc(dev, "Amlogic aml8726 GPIO");
return (BUS_PROBE_DEFAULT);
}
static int
aml8726_gpio_attach(device_t dev)
{
struct aml8726_gpio_softc *sc = device_get_softc(dev);
phandle_t node;
pcell_t prop;
sc->dev = dev;
node = ofw_bus_get_node(dev);
if (OF_getencprop(node, "pin-count",
&prop, sizeof(prop)) <= 0) {
device_printf(dev, "missing pin-count attribute in FDT\n");
return (ENXIO);
}
sc->npins = prop;
if (sc->npins > 32)
return (ENXIO);
if (bus_alloc_resources(dev, aml8726_gpio_spec, sc->res)) {
device_printf(dev, "can not allocate resources for device\n");
return (ENXIO);
}
/*
* The GPIOAO OUT bits occupy the upper word of the OEN register.
*/
if (rman_get_start(sc->res[1]) == rman_get_start(sc->res[0]))
if (sc->npins > 16) {
device_printf(dev,
"too many pins for overlapping OEN and OUT\n");
bus_release_resources(dev, aml8726_gpio_spec, sc->res);
return (ENXIO);
}
AML_GPIO_LOCK_INIT(sc);
sc->busdev = gpiobus_attach_bus(dev);
if (sc->busdev == NULL) {
AML_GPIO_LOCK_DESTROY(sc);
bus_release_resources(dev, aml8726_gpio_spec, sc->res);
return (ENXIO);
}
return (0);
}
static int
aml8726_gpio_detach(device_t dev)
{
struct aml8726_gpio_softc *sc = device_get_softc(dev);
gpiobus_detach_bus(dev);
AML_GPIO_LOCK_DESTROY(sc);
bus_release_resources(dev, aml8726_gpio_spec, sc->res);
return (0);
}
static device_t
aml8726_gpio_get_bus(device_t dev)
{
struct aml8726_gpio_softc *sc = device_get_softc(dev);
return (sc->busdev);
}
static int
aml8726_gpio_pin_max(device_t dev, int *maxpin)
{
struct aml8726_gpio_softc *sc = device_get_softc(dev);
*maxpin = (int)sc->npins;
return (0);
}
/* Get a specific pin's capabilities. */
static int
aml8726_gpio_pin_getcaps(device_t dev, uint32_t pin, uint32_t *caps)
{
struct aml8726_gpio_softc *sc = device_get_softc(dev);
if (pin >= sc->npins)
return (EINVAL);
*caps = (GPIO_PIN_INPUT | GPIO_PIN_OUTPUT);
return (0);
}
/* Get a specific pin's name. */
static int
aml8726_gpio_pin_getname(device_t dev, uint32_t pin, char *name)
{
struct aml8726_gpio_softc *sc = device_get_softc(dev);
if (pin >= sc->npins)
return (EINVAL);
snprintf(name, GPIOMAXNAME, "%s.%u", ofw_bus_get_name(dev), pin);
return (0);
}
/* Get a specific pin's current in/out state. */
static int
aml8726_gpio_pin_getflags(device_t dev, uint32_t pin, uint32_t *flags)
{
struct aml8726_gpio_softc *sc = device_get_softc(dev);
uint32_t mask = 1U << pin;
if (pin >= sc->npins)
return (EINVAL);
if ((CSR_READ_4(sc, AML_GPIO_OE_N_REG) & mask) == 0) {
/* output */
*flags = GPIO_PIN_OUTPUT;
} else
/* input */
*flags = GPIO_PIN_INPUT;
return (0);
}
/* Set a specific pin's in/out state. */
static int
aml8726_gpio_pin_setflags(device_t dev, uint32_t pin, uint32_t flags)
{
struct aml8726_gpio_softc *sc = device_get_softc(dev);
uint32_t mask = 1U << pin;
if (pin >= sc->npins)
return (EINVAL);
AML_GPIO_LOCK(sc);
if ((flags & GPIO_PIN_OUTPUT) != 0) {
/* Output. Turn on driver. */
CSR_WRITE_4(sc, AML_GPIO_OE_N_REG,
(CSR_READ_4(sc, AML_GPIO_OE_N_REG) & ~mask));
} else {
/* Input. Turn off driver. */
CSR_WRITE_4(sc, AML_GPIO_OE_N_REG,
(CSR_READ_4(sc, AML_GPIO_OE_N_REG) | mask));
}
AML_GPIO_UNLOCK(sc);
return (0);
}
/* Set a specific output pin's value. */
static int
aml8726_gpio_pin_set(device_t dev, uint32_t pin, unsigned int value)
{
struct aml8726_gpio_softc *sc = device_get_softc(dev);
uint32_t mask;
if (pin >= sc->npins || value > 1)
return (EINVAL);
/*
* The GPIOAO OUT bits occupy the upper word of the OEN register.
*/
if (rman_get_start(sc->res[1]) == rman_get_start(sc->res[0]))
pin += 16;
mask = 1U << pin;
AML_GPIO_LOCK(sc);
CSR_WRITE_4(sc, AML_GPIO_OUT_REG,
((CSR_READ_4(sc, AML_GPIO_OUT_REG) & ~mask) | (value << pin)));
AML_GPIO_UNLOCK(sc);
return (0);
}
/* Get a specific pin's input value. */
static int
aml8726_gpio_pin_get(device_t dev, uint32_t pin, unsigned int *value)
{
struct aml8726_gpio_softc *sc = device_get_softc(dev);
uint32_t mask = 1U << pin;
if (pin >= sc->npins)
return (EINVAL);
*value = (CSR_READ_4(sc, AML_GPIO_IN_REG) & mask) ? 1 : 0;
return (0);
}
/* Toggle a pin's output value. */
static int
aml8726_gpio_pin_toggle(device_t dev, uint32_t pin)
{
struct aml8726_gpio_softc *sc = device_get_softc(dev);
uint32_t mask;
if (pin >= sc->npins)
return (EINVAL);
/*
* The GPIOAO OUT bits occupy the upper word of the OEN register.
*/
if (rman_get_start(sc->res[1]) == rman_get_start(sc->res[0]))
pin += 16;
mask = 1U << pin;
AML_GPIO_LOCK(sc);
CSR_WRITE_4(sc, AML_GPIO_OUT_REG,
CSR_READ_4(sc, AML_GPIO_OUT_REG) ^ mask);
AML_GPIO_UNLOCK(sc);
return (0);
}
static phandle_t
aml8726_gpio_get_node(device_t bus, device_t dev)
{
/* We only have one child, the GPIO bus, which needs our own node. */
return (ofw_bus_get_node(bus));
}
static device_method_t aml8726_gpio_methods[] = {
/* Device interface */
DEVMETHOD(device_probe, aml8726_gpio_probe),
DEVMETHOD(device_attach, aml8726_gpio_attach),
DEVMETHOD(device_detach, aml8726_gpio_detach),
/* GPIO interface */
DEVMETHOD(gpio_get_bus, aml8726_gpio_get_bus),
DEVMETHOD(gpio_pin_max, aml8726_gpio_pin_max),
DEVMETHOD(gpio_pin_getname, aml8726_gpio_pin_getname),
DEVMETHOD(gpio_pin_getflags, aml8726_gpio_pin_getflags),
DEVMETHOD(gpio_pin_getcaps, aml8726_gpio_pin_getcaps),
DEVMETHOD(gpio_pin_setflags, aml8726_gpio_pin_setflags),
DEVMETHOD(gpio_pin_get, aml8726_gpio_pin_get),
DEVMETHOD(gpio_pin_set, aml8726_gpio_pin_set),
DEVMETHOD(gpio_pin_toggle, aml8726_gpio_pin_toggle),
/* ofw_bus interface */
DEVMETHOD(ofw_bus_get_node, aml8726_gpio_get_node),
DEVMETHOD_END
};
static driver_t aml8726_gpio_driver = {
"gpio",
aml8726_gpio_methods,
sizeof(struct aml8726_gpio_softc),
};
static devclass_t aml8726_gpio_devclass;
DRIVER_MODULE(aml8726_gpio, simplebus, aml8726_gpio_driver,
aml8726_gpio_devclass, 0, 0);