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Diffstat (limited to 'sys/arm/amlogic/aml8726/aml8726_gpio.c')
-rw-r--r--sys/arm/amlogic/aml8726/aml8726_gpio.c372
1 files changed, 372 insertions, 0 deletions
diff --git a/sys/arm/amlogic/aml8726/aml8726_gpio.c b/sys/arm/amlogic/aml8726/aml8726_gpio.c
new file mode 100644
index 0000000..afc6f5b
--- /dev/null
+++ b/sys/arm/amlogic/aml8726/aml8726_gpio.c
@@ -0,0 +1,372 @@
+/*-
+ * 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/fdt/fdt_common.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);
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