gpiic_opb.c revision 1.6
1 /* $NetBSD: gpiic_opb.c,v 1.6 2008/07/12 02:04:07 tsutsui 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 } 246
Indexes created Sun Nov 02 23:10:09 GMT 2025