gpiic_opb.c revision 1.13
1 /* $NetBSD: gpiic_opb.c,v 1.13 2025/09/15 13:23:02 thorpej 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/cpu.h> 51 #include <powerpc/ibm4xx/dev/opbvar.h> 52 #include <powerpc/ibm4xx/dev/gpiicreg.h> 53 54 struct gpiic_softc { 55 device_t sc_dev; 56 bus_space_tag_t sc_bust; 57 bus_space_handle_t sc_bush; 58 uint8_t sc_txen; 59 uint8_t sc_tx; 60 struct i2c_controller sc_i2c; 61 struct i2c_bitbang_ops sc_bops; 62 }; 63 64 static int gpiic_match(device_t, cfdata_t, void *); 65 static void gpiic_attach(device_t, device_t, void *); 66 67 CFATTACH_DECL_NEW(gpiic, sizeof(struct gpiic_softc), 68 gpiic_match, gpiic_attach, NULL, NULL); 69 70 static int gpiic_send_start(void *, int); 71 static int gpiic_send_stop(void *, int); 72 static int gpiic_initiate_xfer(void *, i2c_addr_t, int); 73 static int gpiic_read_byte(void *, uint8_t *, int); 74 static int gpiic_write_byte(void *, uint8_t, int); 75 static void gpiic_set_dir(void *, uint32_t); 76 static void gpiic_set_bits(void *, uint32_t); 77 static uint32_t gpiic_read_bits(void *); 78 79 static int 80 gpiic_match(device_t parent, cfdata_t cf, void *args) 81 { 82 struct opb_attach_args * const oaa = args; 83 84 if (strcmp(oaa->opb_name, cf->cf_name) != 0) 85 return 0; 86 87 return (1); 88 } 89 90 static void 91 gpiic_attach(device_t parent, device_t self, void *args) 92 { 93 struct gpiic_softc * const sc = device_private(self); 94 struct opb_attach_args * const oaa = args; 95 96 aprint_naive(": IIC controller\n"); 97 aprint_normal(": On-Chip IIC controller\n"); 98 99 sc->sc_dev = self; 100 sc->sc_bust = oaa->opb_bt; 101 102 bus_space_map(sc->sc_bust, oaa->opb_addr, IIC_NREG, 0, &sc->sc_bush); 103 104 sc->sc_txen = 0; 105 sc->sc_tx = IIC_DIRECTCNTL_SCC | IIC_DIRECTCNTL_SDAC; 106 iic_tag_init(&sc->sc_i2c); 107 sc->sc_i2c.ic_cookie = sc; 108 sc->sc_i2c.ic_send_start = gpiic_send_start; 109 sc->sc_i2c.ic_send_stop = gpiic_send_stop; 110 sc->sc_i2c.ic_initiate_xfer = gpiic_initiate_xfer; 111 sc->sc_i2c.ic_read_byte = gpiic_read_byte; 112 sc->sc_i2c.ic_write_byte = gpiic_write_byte; 113 114 sc->sc_bops.ibo_set_dir = gpiic_set_dir; 115 sc->sc_bops.ibo_set_bits = gpiic_set_bits; 116 sc->sc_bops.ibo_read_bits = gpiic_read_bits; 117 sc->sc_bops.ibo_bits[I2C_BIT_SDA] = IIC_DIRECTCNTL_SDAC; 118 sc->sc_bops.ibo_bits[I2C_BIT_SCL] = IIC_DIRECTCNTL_SCC; 119 sc->sc_bops.ibo_bits[I2C_BIT_OUTPUT] = 1; 120 sc->sc_bops.ibo_bits[I2C_BIT_INPUT] = 0; 121 122 /* 123 * Put the controller into Soft Reset. This allows us to 124 * manually bit-bang the I2C clock/data lines. 125 */ 126 bus_space_write_1(sc->sc_bust, sc->sc_bush, IIC_XTCNTLSS, 127 IIC_XTCNTLSS_SRST); 128 delay(10); 129 bus_space_write_1(sc->sc_bust, sc->sc_bush, IIC_DIRECTCNTL, 130 IIC_DIRECTCNTL_SCC | IIC_DIRECTCNTL_SDAC); 131 132 iicbus_attach(self, &sc->sc_i2c); 133 } 134 135 static int 136 gpiic_send_start(void *arg, int flags) 137 { 138 struct gpiic_softc * const sc = arg; 139 140 return (i2c_bitbang_send_start(sc, flags, &sc->sc_bops)); 141 } 142 143 static int 144 gpiic_send_stop(void *arg, int flags) 145 { 146 struct gpiic_softc * const sc = arg; 147 148 return (i2c_bitbang_send_stop(sc, flags, &sc->sc_bops)); 149 } 150 151 static int 152 gpiic_initiate_xfer(void *arg, i2c_addr_t addr, int flags) 153 { 154 struct gpiic_softc * const sc = arg; 155 156 return (i2c_bitbang_initiate_xfer(sc, addr, flags, &sc->sc_bops)); 157 } 158 159 static int 160 gpiic_read_byte(void *arg, uint8_t *vp, int flags) 161 { 162 struct gpiic_softc * const sc = arg; 163 164 return (i2c_bitbang_read_byte(sc, vp, flags, &sc->sc_bops)); 165 } 166 167 static int 168 gpiic_write_byte(void *arg, uint8_t v, int flags) 169 { 170 struct gpiic_softc * const sc = arg; 171 172 return (i2c_bitbang_write_byte(sc, v, flags, &sc->sc_bops)); 173 } 174 175 static void 176 gpiic_set_dir(void *arg, uint32_t bits) 177 { 178 struct gpiic_softc * const sc = arg; 179 uint8_t tx, txen; 180 181 txen = (uint8_t)bits; 182 if (sc->sc_txen == txen) 183 return; 184 185 sc->sc_txen = txen; 186 187 tx = sc->sc_tx; 188 if (sc->sc_txen == 0) 189 tx |= IIC_DIRECTCNTL_SDAC; 190 bus_space_write_1(sc->sc_bust, sc->sc_bush, IIC_DIRECTCNTL, tx); 191 } 192 193 static void 194 gpiic_set_bits(void *arg, uint32_t bits) 195 { 196 struct gpiic_softc * const sc = arg; 197 198 sc->sc_tx = (uint8_t)bits; 199 if (sc->sc_txen == 0) 200 bits |= IIC_DIRECTCNTL_SDAC; 201 202 bus_space_write_1(sc->sc_bust, sc->sc_bush, IIC_DIRECTCNTL, bits); 203 } 204 205 static uint32_t 206 gpiic_read_bits(void *arg) 207 { 208 struct gpiic_softc * const sc = arg; 209 uint8_t rv; 210 211 rv = bus_space_read_1(sc->sc_bust, sc->sc_bush, IIC_DIRECTCNTL) << 2; 212 rv &= (IIC_DIRECTCNTL_SCC | IIC_DIRECTCNTL_SDAC); 213 214 return ((uint32_t)rv); 215 } 216
Indexes created Sun Nov 02 07:10:05 GMT 2025