freebsd-skq/sys/arm/amlogic/aml8726/aml8726_i2c.c
ganbold 2c7cd4307b This modifies several FreeBSD drivers to use the hardware strings
present in the GNU dts files.

Submitted by:  John Wehle
Reviewed by:   imp
2015-04-11 08:30:37 +00:00

285 lines
7.0 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 I2C driver.
*
* Currently this implementation doesn't take full advantage of the hardware.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/conf.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/mbuf.h>
#include <sys/malloc.h>
#include <sys/module.h>
#include <sys/mutex.h>
#include <sys/rman.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/iicbus/iiconf.h>
#include <dev/iicbus/iicbus.h>
#include "iicbb_if.h"
struct aml8726_iic_softc {
device_t dev;
struct resource *res[1];
struct mtx mtx;
device_t iicbb;
};
static struct resource_spec aml8726_iic_spec[] = {
{ SYS_RES_MEMORY, 0, RF_ACTIVE },
{ -1, 0 }
};
#define AML_I2C_LOCK(sc) mtx_lock(&(sc)->mtx)
#define AML_I2C_UNLOCK(sc) mtx_unlock(&(sc)->mtx)
#define AML_I2C_LOCK_INIT(sc) \
mtx_init(&(sc)->mtx, device_get_nameunit((sc)->dev), \
"i2c", MTX_DEF)
#define AML_I2C_LOCK_DESTROY(sc) mtx_destroy(&(sc)->mtx);
#define AML_I2C_CTRL_REG 0
#define AML_I2C_MANUAL_SDA_I (1 << 26)
#define AML_I2C_MANUAL_SCL_I (1 << 25)
#define AML_I2C_MANUAL_SDA_O (1 << 24)
#define AML_I2C_MANUAL_SCL_O (1 << 23)
#define AML_I2C_MANUAL_EN (1 << 22)
#define CSR_WRITE_4(sc, reg, val) bus_write_4((sc)->res[0], reg, (val))
#define CSR_READ_4(sc, reg) bus_read_4((sc)->res[0], reg)
static int
aml8726_iic_probe(device_t dev)
{
if (!ofw_bus_status_okay(dev))
return (ENXIO);
if (!ofw_bus_is_compatible(dev, "amlogic,meson6-i2c"))
return (ENXIO);
device_set_desc(dev, "Amlogic aml8726 I2C");
return (BUS_PROBE_DEFAULT);
}
static int
aml8726_iic_attach(device_t dev)
{
struct aml8726_iic_softc *sc = device_get_softc(dev);
int error;
sc->dev = dev;
if (bus_alloc_resources(dev, aml8726_iic_spec, sc->res)) {
device_printf(dev, "can not allocate resources for device\n");
return (ENXIO);
}
AML_I2C_LOCK_INIT(sc);
sc->iicbb = device_add_child(dev, "iicbb", -1);
if (sc->iicbb == NULL) {
device_printf(dev, "could not add iicbb\n");
error = ENXIO;
goto fail;
}
error = device_probe_and_attach(sc->iicbb);
if (error) {
device_printf(dev, "could not attach iicbb\n");
goto fail;
}
return (0);
fail:
AML_I2C_LOCK_DESTROY(sc);
bus_release_resources(dev, aml8726_iic_spec, sc->res);
return (error);
}
static int
aml8726_iic_detach(device_t dev)
{
struct aml8726_iic_softc *sc = device_get_softc(dev);
device_t child;
/*
* Detach the children before recursively deleting
* in case a child has a pointer to a grandchild
* which is used by the child's detach routine.
*
* Remember the child before detaching so we can
* delete it (bus_generic_detach indirectly zeroes
* sc->child_dev).
*/
child = sc->iicbb;
bus_generic_detach(dev);
if (child)
device_delete_child(dev, child);
AML_I2C_LOCK_DESTROY(sc);
bus_release_resources(dev, aml8726_iic_spec, sc->res);
return (0);
}
static void
aml8726_iic_child_detached(device_t dev, device_t child)
{
struct aml8726_iic_softc *sc = device_get_softc(dev);
if (child == sc->iicbb)
sc->iicbb = NULL;
}
static int
aml8726_iic_callback(device_t dev, int index, caddr_t data)
{
return (0);
}
static int
aml8726_iic_reset(device_t dev, u_char speed, u_char addr, u_char *oldaddr)
{
struct aml8726_iic_softc *sc = device_get_softc(dev);
AML_I2C_LOCK(sc);
CSR_WRITE_4(sc, AML_I2C_CTRL_REG,
(CSR_READ_4(sc, AML_I2C_CTRL_REG) | AML_I2C_MANUAL_SDA_O |
AML_I2C_MANUAL_SCL_O | AML_I2C_MANUAL_EN));
AML_I2C_UNLOCK(sc);
/* Wait for 10 usec */
DELAY(10);
return (IIC_ENOADDR);
}
static int
aml8726_iic_getscl(device_t dev)
{
struct aml8726_iic_softc *sc = device_get_softc(dev);
return (CSR_READ_4(sc, AML_I2C_CTRL_REG) & AML_I2C_MANUAL_SCL_I);
}
static int
aml8726_iic_getsda(device_t dev)
{
struct aml8726_iic_softc *sc = device_get_softc(dev);
return (CSR_READ_4(sc, AML_I2C_CTRL_REG) & AML_I2C_MANUAL_SDA_I);
}
static void
aml8726_iic_setscl(device_t dev, int val)
{
struct aml8726_iic_softc *sc = device_get_softc(dev);
AML_I2C_LOCK(sc);
CSR_WRITE_4(sc, AML_I2C_CTRL_REG, ((CSR_READ_4(sc, AML_I2C_CTRL_REG) &
~AML_I2C_MANUAL_SCL_O) | (val ? AML_I2C_MANUAL_SCL_O : 0) |
AML_I2C_MANUAL_EN));
AML_I2C_UNLOCK(sc);
}
static void
aml8726_iic_setsda(device_t dev, int val)
{
struct aml8726_iic_softc *sc = device_get_softc(dev);
AML_I2C_LOCK(sc);
CSR_WRITE_4(sc, AML_I2C_CTRL_REG, ((CSR_READ_4(sc, AML_I2C_CTRL_REG) &
~AML_I2C_MANUAL_SDA_O) | (val ? AML_I2C_MANUAL_SDA_O : 0) |
AML_I2C_MANUAL_EN));
AML_I2C_UNLOCK(sc);
}
static device_method_t aml8726_iic_methods[] = {
/* Device interface */
DEVMETHOD(device_probe, aml8726_iic_probe),
DEVMETHOD(device_attach, aml8726_iic_attach),
DEVMETHOD(device_detach, aml8726_iic_detach),
/* bus interface */
DEVMETHOD(bus_child_detached, aml8726_iic_child_detached),
DEVMETHOD(bus_print_child, bus_generic_print_child),
DEVMETHOD(bus_driver_added, bus_generic_driver_added),
/* IICBB interface */
DEVMETHOD(iicbb_callback, aml8726_iic_callback),
DEVMETHOD(iicbb_reset, aml8726_iic_reset),
DEVMETHOD(iicbb_getscl, aml8726_iic_getscl),
DEVMETHOD(iicbb_getsda, aml8726_iic_getsda),
DEVMETHOD(iicbb_setscl, aml8726_iic_setscl),
DEVMETHOD(iicbb_setsda, aml8726_iic_setsda),
DEVMETHOD_END
};
static driver_t aml8726_iic_driver = {
"aml8726_iic",
aml8726_iic_methods,
sizeof(struct aml8726_iic_softc),
};
static devclass_t aml8726_iic_devclass;
DRIVER_MODULE(aml8726_iic, simplebus, aml8726_iic_driver,
aml8726_iic_devclass, 0, 0);
DRIVER_MODULE(iicbb, aml8726_iic, iicbb_driver, iicbb_devclass, 0, 0);
MODULE_DEPEND(aml8726_iic, iicbb, IICBB_MINVER, IICBB_PREFVER, IICBB_MAXVER);
MODULE_VERSION(aml8726_iic, 1);