sys/arch/powerpc/ibm4xx/dev/gpiic_opb.c

   1 /*      $NetBSD: gpiic_opb.c,v 1.5 2007/12/06 17:00:33 ad Exp $ */
   2
   3 /*
   4  * Copyright 2002, 2003 Wasabi Systems, Inc.
   5  * All rights reserved.
   6  *
   7  * Written by Steve C. Woodford for Wasabi Systems, Inc.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  * 3. All advertising materials mentioning features or use of this software
  18  *    must display the following acknowledgement:
  19  *      This product includes software developed for the NetBSD Project by
  20  *      Wasabi Systems, Inc.
  21  * 4. The name of Wasabi Systems, Inc. may not be used to endorse
  22  *    or promote products derived from this software without specific prior
  23  *    written permission.
  24  *
  25  * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
  26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  27  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  28  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
  29  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  30  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  31  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  32  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  33  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  34  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  35  * POSSIBILITY OF SUCH DAMAGE.
  36  */
  37
  38 #include "locators.h"
  39
  40 #include <sys/param.h>
  41 #include <sys/systm.h>
  42 #include <sys/device.h>
  43 #include <sys/errno.h>
  44 #include <sys/mutex.h>
  45 #include <sys/cpu.h>
  46
  47 #include <dev/i2c/i2cvar.h>
  48 #include <dev/i2c/i2c_bitbang.h>
  49
  50 #include <powerpc/ibm4xx/dev/opbvar.h>
  51 #include <powerpc/ibm4xx/dev/gpiicreg.h>
  52
  53 struct gpiic_softc {
  54         struct device sc_dev;
  55         bus_space_tag_t sc_bust;
  56         bus_space_handle_t sc_bush;
  57         uint8_t sc_txen;
  58         uint8_t sc_tx;
  59         struct i2c_controller sc_i2c;
  60         struct i2c_bitbang_ops sc_bops;
  61         kmutex_t sc_buslock;
  62 };
  63
  64 static int      gpiic_match(struct device *, struct cfdata *, void *);
  65 static void     gpiic_attach(struct device *, struct device *, void *);
  66
  67 CFATTACH_DECL(gpiic, sizeof(struct gpiic_softc),
  68     gpiic_match, gpiic_attach, NULL, NULL);
  69
  70 static int      gpiic_acquire_bus(void *, int);
  71 static void     gpiic_release_bus(void *, int);
  72 static int      gpiic_send_start(void *, int);
  73 static int      gpiic_send_stop(void *, int);
  74 static int      gpiic_initiate_xfer(void *, i2c_addr_t, int);
  75 static int      gpiic_read_byte(void *, uint8_t *, int);
  76 static int      gpiic_write_byte(void *, uint8_t, int);
  77 static void     gpiic_set_dir(void *, uint32_t);
  78 static void     gpiic_set_bits(void *, uint32_t);
  79 static uint32_t gpiic_read_bits(void *);
  80
  81 static int
  82 gpiic_match(struct device *parent, struct cfdata *cf, void *args)
  83 {
  84         struct opb_attach_args *oaa = args;
  85
  86         if (strcmp(oaa->opb_name, cf->cf_name) != 0)
  87                 return 0;
  88
  89         return (1);
  90 }
  91
  92 static void
  93 gpiic_attach(struct device *parent, struct device *self, void *args)
  94 {
  95         struct gpiic_softc *sc = (struct gpiic_softc *)self;
  96         struct opb_attach_args *oaa = args;
  97         struct i2cbus_attach_args iba;
  98
  99         aprint_naive(": IIC controller\n");
 100         aprint_normal(": On-Chip IIC controller\n");
 101
 102         sc->sc_bust = oaa->opb_bt;
 103
 104         bus_space_map(sc->sc_bust, oaa->opb_addr, IIC_NREG, 0, &sc->sc_bush);
 105
 106         mutex_init(&sc->sc_buslock, MUTEX_DEFAULT, IPL_NONE);
 107
 108         sc->sc_txen = 0;
 109         sc->sc_tx = IIC_DIRECTCNTL_SCC | IIC_DIRECTCNTL_SDAC;
 110         sc->sc_i2c.ic_cookie = sc;
 111         sc->sc_i2c.ic_acquire_bus = gpiic_acquire_bus;
 112         sc->sc_i2c.ic_release_bus = gpiic_release_bus;
 113         sc->sc_i2c.ic_exec = NULL;
 114         sc->sc_i2c.ic_send_start = gpiic_send_start;
 115         sc->sc_i2c.ic_send_stop = gpiic_send_stop;
 116         sc->sc_i2c.ic_initiate_xfer = gpiic_initiate_xfer;
 117         sc->sc_i2c.ic_read_byte = gpiic_read_byte;
 118         sc->sc_i2c.ic_write_byte = gpiic_write_byte;
 119
 120         sc->sc_bops.ibo_set_dir = gpiic_set_dir;
 121         sc->sc_bops.ibo_set_bits = gpiic_set_bits;
 122         sc->sc_bops.ibo_read_bits = gpiic_read_bits;
 123         sc->sc_bops.ibo_bits[I2C_BIT_SDA] = IIC_DIRECTCNTL_SDAC;
 124         sc->sc_bops.ibo_bits[I2C_BIT_SCL] = IIC_DIRECTCNTL_SCC;
 125         sc->sc_bops.ibo_bits[I2C_BIT_OUTPUT] = 1;
 126         sc->sc_bops.ibo_bits[I2C_BIT_INPUT] = 0;
 127
 128         /*
 129          * Put the controller into Soft Reset. This allows us to
 130          * manually bit-bang the I2C clock/data lines.
 131          */
 132         bus_space_write_1(sc->sc_bust, sc->sc_bush, IIC_XTCNTLSS,
 133             IIC_XTCNTLSS_SRST);
 134         delay(10);
 135         bus_space_write_1(sc->sc_bust, sc->sc_bush, IIC_DIRECTCNTL,
 136             IIC_DIRECTCNTL_SCC | IIC_DIRECTCNTL_SDAC);
 137
 138         iba.iba_tag = &sc->sc_i2c;
 139         (void) config_found_ia(&sc->sc_dev, "i2cbus", &iba, iicbus_print);
 140 }
 141
 142 static int
 143 gpiic_acquire_bus(void *arg, int flags)
 144 {
 145         struct gpiic_softc *sc = arg;
 146
 147         if (flags & I2C_F_POLL)
 148                 return (0);
 149
 150         mutex_enter(&sc->sc_buslock);
 151         return (0);
 152 }
 153
 154 static void
 155 gpiic_release_bus(void *arg, int flags)
 156 {
 157         struct gpiic_softc *sc = arg;
 158
 159         if (flags & I2C_F_POLL)
 160                 return;
 161
 162         mutex_exit(&sc->sc_buslock);
 163 }
 164
 165 static int
 166 gpiic_send_start(void *arg, int flags)
 167 {
 168         struct gpiic_softc *sc = arg;
 169
 170         return (i2c_bitbang_send_start(sc, flags, &sc->sc_bops));
 171 }
 172
 173 static int
 174 gpiic_send_stop(void *arg, int flags)
 175 {
 176         struct gpiic_softc *sc = arg;
 177
 178         return (i2c_bitbang_send_stop(sc, flags, &sc->sc_bops));
 179 }
 180
 181 static int
 182 gpiic_initiate_xfer(void *arg, i2c_addr_t addr, int flags)
 183 {
 184         struct gpiic_softc *sc = arg;
 185
 186         return (i2c_bitbang_initiate_xfer(sc, addr, flags, &sc->sc_bops));
 187 }
 188
 189 static int
 190 gpiic_read_byte(void *arg, uint8_t *vp, int flags)
 191 {
 192         struct gpiic_softc *sc = arg;
 193
 194         return (i2c_bitbang_read_byte(sc, vp, flags, &sc->sc_bops));
 195 }
 196
 197 static int
 198 gpiic_write_byte(void *arg, uint8_t v, int flags)
 199 {
 200         struct gpiic_softc *sc = arg;
 201
 202         return (i2c_bitbang_write_byte(sc, v, flags, &sc->sc_bops));
 203 }
 204
 205 static void
 206 gpiic_set_dir(void *arg, uint32_t bits)
 207 {
 208         struct gpiic_softc *sc = arg;
 209         uint8_t tx, txen;
 210
 211         txen = (uint8_t)bits;
 212         if (sc->sc_txen == txen)
 213                 return;
 214
 215         sc->sc_txen = txen;
 216
 217         tx = sc->sc_tx;
 218         if (sc->sc_txen == 0)
 219                 tx |= IIC_DIRECTCNTL_SDAC;
 220         bus_space_write_1(sc->sc_bust, sc->sc_bush, IIC_DIRECTCNTL, tx);
 221 }
 222
 223 static void
 224 gpiic_set_bits(void *arg, uint32_t bits)
 225 {
 226         struct gpiic_softc *sc = arg;
 227
 228         sc->sc_tx = (uint8_t)bits;
 229         if (sc->sc_txen == 0)
 230                 bits |= IIC_DIRECTCNTL_SDAC;
 231
 232         bus_space_write_1(sc->sc_bust, sc->sc_bush, IIC_DIRECTCNTL, bits);
 233 }
 234
 235 static uint32_t
 236 gpiic_read_bits(void *arg)
 237 {
 238         struct gpiic_softc *sc = arg;
 239         uint8_t rv;
 240
 241         rv = bus_space_read_1(sc->sc_bust, sc->sc_bush, IIC_DIRECTCNTL) << 2;
 242         rv &= (IIC_DIRECTCNTL_SCC | IIC_DIRECTCNTL_SDAC);
 243
 244         return ((uint32_t)rv);
 245 }