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[src/trunk]: src/sys/arch/arm/samsung Provide bitbanging IIC for Samsung's Ex...
details: https://anonhg.NetBSD.org/src/rev/48890b03a816
branches: trunk
changeset: 329364:48890b03a816
user: reinoud <reinoud%NetBSD.org@localhost>
date: Wed May 21 12:19:59 2014 +0000
description:
Provide bitbanging IIC for Samsung's Exynos
diffstat:
sys/arch/arm/samsung/exynos_i2c.c | 392 ++++++++++++++++++++++++++++++++++++++
sys/arch/arm/samsung/files.exynos | 7 +-
2 files changed, 398 insertions(+), 1 deletions(-)
diffs (truncated from 414 to 300 lines):
diff -r 259f3c171f3c -r 48890b03a816 sys/arch/arm/samsung/exynos_i2c.c
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/sys/arch/arm/samsung/exynos_i2c.c Wed May 21 12:19:59 2014 +0000
@@ -0,0 +1,392 @@
+/* $NetBSD: exynos_i2c.c,v 1.1 2014/05/21 12:19:59 reinoud Exp $ */
+
+/*
+ * Copyright (c) 2014 The NetBSD Foundation, Inc.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to The NetBSD Foundation
+ * by Reinoud Zandijk.
+ *
+ * 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
+ *
+ */
+
+
+#include "opt_exynos.h"
+#include "opt_arm_debug.h"
+#include "exynos_iic.h"
+
+#include <sys/cdefs.h>
+__KERNEL_RCSID(0, "$NetBSD: exynos_i2c.c,v 1.1 2014/05/21 12:19:59 reinoud Exp $");
+
+
+#include <sys/param.h>
+#include <sys/bus.h>
+#include <sys/device.h>
+#include <sys/intr.h>
+#include <sys/systm.h>
+#include <sys/kmem.h>
+
+#include <arm/samsung/exynos_reg.h>
+#include <arm/samsung/exynos_io.h>
+#include <arm/samsung/exynos_intr.h>
+
+#include <sys/gpio.h>
+#include <dev/gpio/gpiovar.h>
+
+#include <dev/i2c/i2cvar.h>
+#include <dev/i2c/i2c_bitbang.h>
+
+
+struct exynos_iic_dev_softc {
+ int isc_bus;
+ bool isc_isgpio;
+
+ bus_space_tag_t isc_bst;
+ bus_space_handle_t isc_bsh;
+
+ struct exynos_gpio_pinset isc_pinset;
+ struct exynos_gpio_pindata isc_sda;
+ struct exynos_gpio_pindata isc_slc;
+ bool isc_sda_is_output;
+
+ kmutex_t isc_buslock;
+ struct i2c_controller isc_i2cbus;
+};
+
+
+#if NEXYNOS_IIC > 0
+static int exynos_iic_acquire_bus(void *, int);
+static void exynos_iic_release_bus(void *, int);
+
+static int exynos_iic_send_start(void *, int);
+static int exynos_iic_send_stop(void *, int);
+static int exynos_iic_initiate_xfer(void *, i2c_addr_t, int);
+static int exynos_iic_read_byte(void *, uint8_t *, int);
+static int exynos_iic_write_byte(void *, uint8_t , int);
+
+static bool exynos_iic_attach_i2cbus(struct exynos_iic_dev_softc *,
+ struct i2c_controller *, struct exyo_locators const *);
+#endif
+
+
+struct i2c_controller *exynos_i2cbus[EXYNOS_MAX_IIC_BUSSES];
+static int exynos_iic_match(device_t, cfdata_t, void *);
+static void exynos_iic_attach(device_t, device_t, void *);
+
+struct exynos_iic_softc {
+ device_t sc_dev;
+
+ struct exynos_iic_dev_softc sc_idevs[EXYNOS_MAX_IIC_BUSSES];
+ struct i2c_controller sc_i2cbus[EXYNOS_MAX_IIC_BUSSES];
+} exynos_iic_sc;
+
+
+CFATTACH_DECL_NEW(exynos_iic, sizeof(struct exynos_iic_softc),
+ exynos_iic_match, exynos_iic_attach, NULL, NULL);
+
+
+static int
+exynos_iic_match(device_t self, cfdata_t cf, void *aux)
+{
+ struct exyo_attach_args *exyoaa = aux;
+ struct exyo_locators *loc = &exyoaa->exyo_loc;
+ int i;
+
+ /* no locators expected */
+ KASSERT(loc->loc_offset == 0);
+ KASSERT(loc->loc_size == 0);
+ KASSERT(loc->loc_port == EXYOCF_PORT_DEFAULT);
+
+ if (exynos_iic_sc.sc_dev != NULL)
+ return 0;
+ for (i = 0; i < EXYNOS_MAX_IIC_BUSSES; i++)
+ exynos_i2cbus[i] = NULL;
+#if NEXYNOS_IIC > 0
+ return 1;
+#else
+ return 0;
+#endif
+}
+
+
+static void
+exynos_iic_attach(device_t parent, device_t self, void *aux)
+{
+#if NEXYNOS_IIC > 0
+ prop_dictionary_t dict = device_properties(self);
+ struct exynos_iic_softc * const sc = device_private(self);
+ struct exyo_attach_args * const exyoaa = aux;
+ struct exynos_iic_dev_softc *ei2c_sc;
+ struct i2c_controller *i2c_cntr;
+ struct i2cbus_attach_args iba;
+ struct exyo_locinfo const *locs;
+ struct exyo_locators const *loc;
+ bool enable;
+ char scrap[strlen("iic??_enable")];
+ int i;
+
+ locs = NULL;
+#ifdef EXYNOS4
+ if (IS_EXYNOS4_P())
+ locs = &exynos4_i2c_locinfo;
+#endif
+#ifdef EXYNOS5
+ if (IS_EXYNOS5_P())
+ locs = &exynos5_i2c_locinfo;
+#endif
+ KASSERT(locs);
+
+ sc->sc_dev = self;
+ if (locs->nlocators == 0) {
+ aprint_error(": no i2c busses defined\n");
+ return;
+ }
+
+ aprint_normal("\n");
+
+ for (i = 0; i < locs->nlocators; i++) {
+ /* get subdriver type : either gpio or hw */
+ snprintf(scrap, sizeof(scrap), "iic%d_enable", i);
+ if (prop_dictionary_get_bool(dict, scrap, &enable)) {
+ if (!enable)
+ continue;
+ /* found an iic device */
+ ei2c_sc = &sc->sc_idevs[i];
+ i2c_cntr = &sc->sc_i2cbus[i];
+ loc = &locs->locators[i];
+
+ ei2c_sc->isc_bus = i;
+ ei2c_sc->isc_isgpio = (loc->loc_flags > 0);
+ mutex_init(&ei2c_sc->isc_buslock, MUTEX_DEFAULT, IPL_NONE);
+
+ ei2c_sc->isc_bst = exyoaa->exyo_core_bst;
+ if (bus_space_subregion(ei2c_sc->isc_bst,
+ exyoaa->exyo_core_bsh,
+ loc->loc_offset, loc->loc_size,
+ &ei2c_sc->isc_bsh)) {
+ aprint_error_dev(self,
+ ": failed to map registers for i2cbus%d\n",
+ i);
+ continue;
+ }
+
+ if (!exynos_iic_attach_i2cbus(ei2c_sc, i2c_cntr, loc))
+ continue;
+
+ exynos_i2cbus[i] = i2c_cntr;
+ iba.iba_tag = i2c_cntr;
+ (void) config_found_ia(sc->sc_dev, "i2cbus", &iba,
+ iicbus_print);
+ }
+ }
+#endif
+}
+
+
+#if NEXYNOS_IIC > 0
+static bool
+exynos_iic_attach_i2cbus(struct exynos_iic_dev_softc *ei2c_sc,
+ struct i2c_controller *i2c_cntr, struct exyo_locators const *loc)
+{
+ struct exynos_gpio_pinset *pinset;
+
+ /* reserve our pins */
+ pinset = &ei2c_sc->isc_pinset;
+ strcpy(pinset->pinset_group, loc->loc_gpio_bus);
+ pinset->pinset_mask = __BIT(loc->loc_sda) | __BIT(loc->loc_slc);
+ pinset->pinset_func = loc->loc_func;
+
+ i2c_cntr->ic_cookie = ei2c_sc;
+ i2c_cntr->ic_acquire_bus = exynos_iic_acquire_bus;
+ i2c_cntr->ic_release_bus = exynos_iic_release_bus;
+ i2c_cntr->ic_send_start = exynos_iic_send_start;
+ i2c_cntr->ic_send_stop = exynos_iic_send_stop;
+ i2c_cntr->ic_initiate_xfer = exynos_iic_initiate_xfer;
+ i2c_cntr->ic_read_byte = exynos_iic_read_byte;
+ i2c_cntr->ic_write_byte = exynos_iic_write_byte;
+
+ exynos_gpio_pinset_acquire(pinset);
+ if (ei2c_sc->isc_isgpio) {
+ /* get sda and slc pins */
+ exynos_gpio_pinset_to_pindata(pinset,
+ loc->loc_sda, &ei2c_sc->isc_sda);
+ exynos_gpio_pinset_to_pindata(pinset,
+ loc->loc_slc, &ei2c_sc->isc_slc);
+ ei2c_sc->isc_sda_is_output = false;
+ exynos_gpio_pindata_ctl(&ei2c_sc->isc_sda, GPIO_PIN_INPUT);
+ exynos_gpio_pindata_ctl(&ei2c_sc->isc_slc, GPIO_PIN_OUTPUT);
+ return 1;
+ } else {
+ /* TBD: attach hardware driver */
+ aprint_normal("i2cbus%d: would attach native i2c driver\n",
+ ei2c_sc->isc_bus);
+ return 0;
+ }
+}
+
+
+#define EXYNOS_IIC_BB_SDA __BIT(1)
+#define EXYNOS_IIC_BB_SCL __BIT(2)
+#define EXYNOS_IIC_BB_SDA_OUT __BIT(3)
+#define EXYNOS_IIC_BB_SDA_IN 0
+
+static void
+exynos_iic_bb_set_bits(void *cookie, uint32_t bits)
+{
+ struct exynos_iic_dev_softc *i2c_sc = cookie;
+ int sda, slc;
+
+ sda = (bits & EXYNOS_IIC_BB_SDA) ? true : false;
+ slc = (bits & EXYNOS_IIC_BB_SCL) ? true : false;
+
+ if (i2c_sc->isc_sda_is_output)
+ exynos_gpio_pindata_write(&i2c_sc->isc_sda, sda);
+ exynos_gpio_pindata_write(&i2c_sc->isc_slc, slc);
+}
+
+static uint32_t
+exynos_iic_bb_read_bits(void *cookie)
+{
+ struct exynos_iic_dev_softc *i2c_sc = cookie;
+ int sda, slc;
+
+ sda = 0;
+ if (!i2c_sc->isc_sda_is_output)
+ sda = exynos_gpio_pindata_read(&i2c_sc->isc_sda);
+ slc = exynos_gpio_pindata_read(&i2c_sc->isc_slc);
+
+ return (sda ? EXYNOS_IIC_BB_SDA : 0) | (slc ? EXYNOS_IIC_BB_SCL : 0);
+}
+
+
+static void
+exynos_iic_bb_set_dir(void *cookie, uint32_t bits)
+{
+ struct exynos_iic_dev_softc *i2c_sc = cookie;
+ int flags;
+
+ flags = GPIO_PIN_INPUT | GPIO_PIN_TRISTATE;
+ i2c_sc->isc_sda_is_output = ((bits & EXYNOS_IIC_BB_SDA_OUT) != 0);
+ if (i2c_sc->isc_sda_is_output)
+ flags = GPIO_PIN_OUTPUT | GPIO_PIN_TRISTATE;
+
+ exynos_gpio_pindata_ctl(&i2c_sc->isc_sda, flags);
+}
+
+
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