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nslu2_iic.c revision 1.1
      1  1.1  scw /*	$NetBSD: nslu2_iic.c,v 1.1 2006/02/28 20:40:33 scw Exp $	*/
      2  1.1  scw 
      3  1.1  scw /*-
      4  1.1  scw  * Copyright (c) 2006 The NetBSD Foundation, Inc.
      5  1.1  scw  * All rights reserved.
      6  1.1  scw  *
      7  1.1  scw  * This code is derived from software contributed to The NetBSD Foundation
      8  1.1  scw  * by Steve C. Woodford.
      9  1.1  scw  *
     10  1.1  scw  * Redistribution and use in source and binary forms, with or without
     11  1.1  scw  * modification, are permitted provided that the following conditions
     12  1.1  scw  * are met:
     13  1.1  scw  * 1. Redistributions of source code must retain the above copyright
     14  1.1  scw  *    notice, this list of conditions and the following disclaimer.
     15  1.1  scw  * 2. Redistributions in binary form must reproduce the above copyright
     16  1.1  scw  *    notice, this list of conditions and the following disclaimer in the
     17  1.1  scw  *    documentation and/or other materials provided with the distribution.
     18  1.1  scw  * 3. All advertising materials mentioning features or use of this software
     19  1.1  scw  *    must display the following acknowledgement:
     20  1.1  scw  *        This product includes software developed by the NetBSD
     21  1.1  scw  *        Foundation, Inc. and its contributors.
     22  1.1  scw  * 4. Neither the name of The NetBSD Foundation nor the names of its
     23  1.1  scw  *    contributors may be used to endorse or promote products derived
     24  1.1  scw  *    from this software without specific prior written permission.
     25  1.1  scw  *
     26  1.1  scw  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     27  1.1  scw  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     28  1.1  scw  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     29  1.1  scw  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     30  1.1  scw  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     31  1.1  scw  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     32  1.1  scw  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     33  1.1  scw  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     34  1.1  scw  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     35  1.1  scw  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     36  1.1  scw  * POSSIBILITY OF SUCH DAMAGE.
     37  1.1  scw  */
     38  1.1  scw 
     39  1.1  scw #include <sys/param.h>
     40  1.1  scw #include <sys/systm.h>
     41  1.1  scw #include <sys/kernel.h>
     42  1.1  scw #include <sys/device.h>
     43  1.1  scw #include <sys/lock.h>
     44  1.1  scw 
     45  1.1  scw #include <machine/bus.h>
     46  1.1  scw 
     47  1.1  scw #include <dev/i2c/i2cvar.h>
     48  1.1  scw #include <dev/i2c/i2c_bitbang.h>
     49  1.1  scw 
     50  1.1  scw #include <arm/xscale/ixp425reg.h>
     51  1.1  scw #include <arm/xscale/ixp425var.h>
     52  1.1  scw 
     53  1.1  scw #include <evbarm/nslu2/nslu2reg.h>
     54  1.1  scw 
     55  1.1  scw struct slugiic_softc {
     56  1.1  scw 	struct device sc_dev;
     57  1.1  scw 	struct i2c_controller sc_ic;
     58  1.1  scw 	struct i2c_bitbang_ops sc_ibo;
     59  1.1  scw 	struct lock sc_lock;
     60  1.1  scw 	uint32_t sc_dirout;
     61  1.1  scw };
     62  1.1  scw 
     63  1.1  scw static int
     64  1.1  scw slugiic_acquire_bus(void *arg, int flags)
     65  1.1  scw {
     66  1.1  scw 	struct slugiic_softc *sc = arg;
     67  1.1  scw 
     68  1.1  scw 	if (flags & I2C_F_POLL)
     69  1.1  scw 		return (0);
     70  1.1  scw 
     71  1.1  scw 	return (lockmgr(&sc->sc_lock, LK_EXCLUSIVE, NULL));
     72  1.1  scw }
     73  1.1  scw 
     74  1.1  scw static void
     75  1.1  scw slugiic_release_bus(void *arg, int flags)
     76  1.1  scw {
     77  1.1  scw 	struct slugiic_softc *sc = arg;
     78  1.1  scw 
     79  1.1  scw 	if (flags & I2C_F_POLL)
     80  1.1  scw 		return;
     81  1.1  scw 
     82  1.1  scw 	(void) lockmgr(&sc->sc_lock, LK_RELEASE, NULL);
     83  1.1  scw }
     84  1.1  scw 
     85  1.1  scw static int
     86  1.1  scw slugiic_send_start(void *arg, int flags)
     87  1.1  scw {
     88  1.1  scw 	struct slugiic_softc *sc = arg;
     89  1.1  scw 
     90  1.1  scw 	return (i2c_bitbang_send_start(sc, flags, &sc->sc_ibo));
     91  1.1  scw }
     92  1.1  scw 
     93  1.1  scw static int
     94  1.1  scw slugiic_send_stop(void *arg, int flags)
     95  1.1  scw {
     96  1.1  scw 	struct slugiic_softc *sc = arg;
     97  1.1  scw 
     98  1.1  scw 	return (i2c_bitbang_send_stop(sc, flags, &sc->sc_ibo));
     99  1.1  scw }
    100  1.1  scw 
    101  1.1  scw static int
    102  1.1  scw slugiic_initiate_xfer(void *arg, i2c_addr_t addr, int flags)
    103  1.1  scw {
    104  1.1  scw 	struct slugiic_softc *sc = arg;
    105  1.1  scw 
    106  1.1  scw 	return (i2c_bitbang_initiate_xfer(sc, addr, flags, &sc->sc_ibo));
    107  1.1  scw }
    108  1.1  scw 
    109  1.1  scw static int
    110  1.1  scw slugiic_read_byte(void *arg, uint8_t *vp, int flags)
    111  1.1  scw {
    112  1.1  scw 	struct slugiic_softc *sc = arg;
    113  1.1  scw 
    114  1.1  scw 	return (i2c_bitbang_read_byte(sc, vp, flags, &sc->sc_ibo));
    115  1.1  scw }
    116  1.1  scw 
    117  1.1  scw static int
    118  1.1  scw slugiic_write_byte(void *arg, uint8_t v, int flags)
    119  1.1  scw {
    120  1.1  scw 	struct slugiic_softc *sc = arg;
    121  1.1  scw 
    122  1.1  scw 	return (i2c_bitbang_write_byte(sc, v, flags, &sc->sc_ibo));
    123  1.1  scw }
    124  1.1  scw 
    125  1.1  scw static void
    126  1.1  scw slugiic_set_dir(void *arg, uint32_t bits)
    127  1.1  scw {
    128  1.1  scw 	struct slugiic_softc *sc = arg;
    129  1.1  scw 	uint32_t reg;
    130  1.1  scw 	int s;
    131  1.1  scw 
    132  1.1  scw 	if (sc->sc_dirout == (bits ^ GPIO_I2C_SDA_BIT))
    133  1.1  scw 		return;
    134  1.1  scw 
    135  1.1  scw 	s = splhigh();
    136  1.1  scw 
    137  1.1  scw 	sc->sc_dirout = bits ^ GPIO_I2C_SDA_BIT;
    138  1.1  scw 
    139  1.1  scw 	reg = GPIO_CONF_READ_4(ixp425_softc, IXP425_GPIO_GPOER);
    140  1.1  scw 	reg &= ~GPIO_I2C_SDA_BIT;
    141  1.1  scw 	GPIO_CONF_WRITE_4(ixp425_softc, IXP425_GPIO_GPOER, reg | bits);
    142  1.1  scw 
    143  1.1  scw 	splx(s);
    144  1.1  scw }
    145  1.1  scw 
    146  1.1  scw static void
    147  1.1  scw slugiic_set_bits(void *arg, uint32_t bits)
    148  1.1  scw {
    149  1.1  scw 	struct slugiic_softc *sc = arg;
    150  1.1  scw 	uint32_t reg;
    151  1.1  scw 	int s;
    152  1.1  scw 
    153  1.1  scw 	if (sc->sc_dirout == 0 && !(bits & GPIO_I2C_SDA_BIT))
    154  1.1  scw 		bits |= GPIO_I2C_SDA_BIT;
    155  1.1  scw 
    156  1.1  scw 	s = splhigh();
    157  1.1  scw 
    158  1.1  scw 	reg = GPIO_CONF_READ_4(ixp425_softc, IXP425_GPIO_GPOUTR);
    159  1.1  scw 	reg &= ~(GPIO_I2C_SDA_BIT | GPIO_I2C_SCL_BIT);
    160  1.1  scw 	GPIO_CONF_WRITE_4(ixp425_softc, IXP425_GPIO_GPOUTR, reg | bits);
    161  1.1  scw 
    162  1.1  scw 	splx(s);
    163  1.1  scw }
    164  1.1  scw 
    165  1.1  scw static uint32_t
    166  1.1  scw slugiic_read_bits(void *arg)
    167  1.1  scw {
    168  1.1  scw 	uint32_t reg;
    169  1.1  scw 
    170  1.1  scw 	reg = GPIO_CONF_READ_4(ixp425_softc, IXP425_GPIO_GPINR);
    171  1.1  scw 	return (reg & (GPIO_I2C_SDA_BIT | GPIO_I2C_SCL_BIT));
    172  1.1  scw }
    173  1.1  scw 
    174  1.1  scw static void
    175  1.1  scw slugiic_deferred_attach(struct device *device)
    176  1.1  scw {
    177  1.1  scw 	struct slugiic_softc *sc = (struct slugiic_softc *)device;
    178  1.1  scw 	struct i2cbus_attach_args iba;
    179  1.1  scw 	uint32_t reg;
    180  1.1  scw 
    181  1.1  scw 	reg = GPIO_CONF_READ_4(ixp425_softc, IXP425_GPIO_GPOUTR);
    182  1.1  scw 	reg |= GPIO_I2C_SDA_BIT | GPIO_I2C_SCL_BIT;
    183  1.1  scw 	GPIO_CONF_WRITE_4(ixp425_softc, IXP425_GPIO_GPOUTR, reg);
    184  1.1  scw 
    185  1.1  scw 	reg = GPIO_CONF_READ_4(ixp425_softc, IXP425_GPIO_GPOER);
    186  1.1  scw 	reg &= ~GPIO_I2C_SCL_BIT;
    187  1.1  scw 	reg |= GPIO_I2C_SDA_BIT;
    188  1.1  scw 	GPIO_CONF_WRITE_4(ixp425_softc, IXP425_GPIO_GPOER, reg);
    189  1.1  scw 
    190  1.1  scw 	iba.iba_name = "iic";
    191  1.1  scw 	iba.iba_tag = &sc->sc_ic;
    192  1.1  scw 	(void) config_found(&sc->sc_dev, &iba, iicbus_print);
    193  1.1  scw }
    194  1.1  scw 
    195  1.1  scw static int
    196  1.1  scw slugiic_match(struct device *parent, struct cfdata *cf, void *arg)
    197  1.1  scw {
    198  1.1  scw 
    199  1.1  scw 	return (1);
    200  1.1  scw }
    201  1.1  scw 
    202  1.1  scw static void
    203  1.1  scw slugiic_attach(struct device *parent, struct device *self, void *arg)
    204  1.1  scw {
    205  1.1  scw 	struct slugiic_softc *sc = (struct slugiic_softc *)self;
    206  1.1  scw 
    207  1.1  scw 	aprint_naive("\n");
    208  1.1  scw 	aprint_normal(": I2C bus\n");
    209  1.1  scw 
    210  1.1  scw 	sc->sc_ic.ic_cookie = sc;
    211  1.1  scw 	sc->sc_ic.ic_acquire_bus = slugiic_acquire_bus;
    212  1.1  scw 	sc->sc_ic.ic_release_bus = slugiic_release_bus;
    213  1.1  scw 	sc->sc_ic.ic_exec = NULL;
    214  1.1  scw 	sc->sc_ic.ic_send_start = slugiic_send_start;
    215  1.1  scw 	sc->sc_ic.ic_send_stop = slugiic_send_stop;
    216  1.1  scw 	sc->sc_ic.ic_initiate_xfer = slugiic_initiate_xfer;
    217  1.1  scw 	sc->sc_ic.ic_read_byte = slugiic_read_byte;
    218  1.1  scw 	sc->sc_ic.ic_write_byte = slugiic_write_byte;
    219  1.1  scw 
    220  1.1  scw 	sc->sc_ibo.ibo_set_dir = slugiic_set_dir;
    221  1.1  scw 	sc->sc_ibo.ibo_set_bits = slugiic_set_bits;
    222  1.1  scw 	sc->sc_ibo.ibo_read_bits = slugiic_read_bits;
    223  1.1  scw 	sc->sc_ibo.ibo_bits[I2C_BIT_SDA] = GPIO_I2C_SDA_BIT;
    224  1.1  scw 	sc->sc_ibo.ibo_bits[I2C_BIT_SCL] = GPIO_I2C_SCL_BIT;
    225  1.1  scw 	sc->sc_ibo.ibo_bits[I2C_BIT_OUTPUT] = 0;
    226  1.1  scw 	sc->sc_ibo.ibo_bits[I2C_BIT_INPUT] = GPIO_I2C_SDA_BIT;
    227  1.1  scw 
    228  1.1  scw 	lockinit(&sc->sc_lock, PRIBIO|PCATCH, "slugiiclk", 0, 0);
    229  1.1  scw 
    230  1.1  scw 	sc->sc_dirout = 0;
    231  1.1  scw 
    232  1.1  scw 	/*
    233  1.1  scw 	 * Defer until ixp425_softc has been initialised
    234  1.1  scw 	 */
    235  1.1  scw 	config_interrupts(self, slugiic_deferred_attach);
    236  1.1  scw }
    237  1.1  scw 
    238  1.1  scw CFATTACH_DECL(slugiic, sizeof(struct slugiic_softc),
    239  1.1  scw     slugiic_match, slugiic_attach, NULL, NULL);
    240