auvitek_i2c.c revision 1.2
1 /* $NetBSD: auvitek_i2c.c,v 1.2 2011/07/09 15:00:45 jmcneill Exp $ */ 2 3 /*- 4 * Copyright (c) 2010 Jared D. McNeill <jmcneill (at) invisible.ca> 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 17 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 18 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 19 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 20 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 26 * POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 /* 30 * Auvitek AU0828 USB controller - I2C access ops 31 */ 32 33 #include <sys/cdefs.h> 34 __KERNEL_RCSID(0, "$NetBSD: auvitek_i2c.c,v 1.2 2011/07/09 15:00:45 jmcneill Exp $"); 35 36 #include <sys/param.h> 37 #include <sys/systm.h> 38 #include <sys/device.h> 39 #include <sys/conf.h> 40 #include <sys/bus.h> 41 #include <sys/module.h> 42 43 #include <dev/usb/usb.h> 44 #include <dev/usb/usbdi.h> 45 #include <dev/usb/usbdi_util.h> 46 #include <dev/usb/usbdevs.h> 47 48 #include <dev/i2c/i2cvar.h> 49 50 #include <dev/usb/auvitekreg.h> 51 #include <dev/usb/auvitekvar.h> 52 53 static int auvitek_i2c_acquire_bus(void *, int); 54 static void auvitek_i2c_release_bus(void *, int); 55 static int auvitek_i2c_exec(void *, i2c_op_t, i2c_addr_t, 56 const void *, size_t, void *, size_t, int); 57 58 static int auvitek_i2c_read(struct auvitek_softc *, i2c_addr_t, 59 uint8_t *, size_t); 60 static int auvitek_i2c_write(struct auvitek_softc *, i2c_addr_t, 61 const uint8_t *, size_t); 62 static bool auvitek_i2c_wait(struct auvitek_softc *); 63 static bool auvitek_i2c_wait_rdack(struct auvitek_softc *); 64 static bool auvitek_i2c_wait_rddone(struct auvitek_softc *); 65 static bool auvitek_i2c_wait_wrdone(struct auvitek_softc *); 66 67 int 68 auvitek_i2c_attach(struct auvitek_softc *sc) 69 { 70 mutex_init(&sc->sc_i2c_lock, MUTEX_DEFAULT, IPL_VM); 71 sc->sc_i2c.ic_cookie = sc; 72 sc->sc_i2c.ic_acquire_bus = auvitek_i2c_acquire_bus; 73 sc->sc_i2c.ic_release_bus = auvitek_i2c_release_bus; 74 sc->sc_i2c.ic_exec = auvitek_i2c_exec; 75 76 return 0; 77 } 78 79 int 80 auvitek_i2c_detach(struct auvitek_softc *sc, int flags) 81 { 82 mutex_destroy(&sc->sc_i2c_lock); 83 84 return 0; 85 } 86 87 static int 88 auvitek_i2c_acquire_bus(void *opaque, int flags) 89 { 90 struct auvitek_softc *sc = opaque; 91 92 mutex_enter(&sc->sc_i2c_lock); 93 94 return 0; 95 } 96 97 static void 98 auvitek_i2c_release_bus(void *opaque, int flags) 99 { 100 struct auvitek_softc *sc = opaque; 101 102 mutex_exit(&sc->sc_i2c_lock); 103 } 104 105 static int 106 auvitek_i2c_exec(void *opaque, i2c_op_t op, i2c_addr_t addr, 107 const void *cmd, size_t cmdlen, void *vbuf, size_t buflen, int flags) 108 { 109 struct auvitek_softc *sc = opaque; 110 111 if (I2C_OP_READ_P(op)) 112 return auvitek_i2c_read(sc, addr, vbuf, buflen); 113 else 114 return auvitek_i2c_write(sc, addr, cmd, cmdlen); 115 } 116 117 static int 118 auvitek_i2c_read(struct auvitek_softc *sc, i2c_addr_t addr, 119 uint8_t *buf, size_t buflen) 120 { 121 uint8_t v; 122 unsigned int i; 123 124 //KASSERT(mutex_owned(&sc->sc_i2c_lock)); 125 126 auvitek_write_1(sc, AU0828_REG_I2C_MBMODE, 1); 127 auvitek_write_1(sc, AU0828_REG_I2C_CLKDIV, sc->sc_i2c_clkdiv); 128 auvitek_write_1(sc, AU0828_REG_I2C_DSTADDR, addr << 1); 129 130 if (buflen == 0) { 131 auvitek_write_1(sc, AU0828_REG_I2C_TRIGGER, 132 AU0828_I2C_TRIGGER_RD); 133 if (auvitek_i2c_wait_rdack(sc) == false) 134 return EBUSY; 135 return 0; 136 } 137 138 for (i = 0; i < buflen; i++) { 139 v = AU0828_I2C_TRIGGER_RD; 140 if (i < (buflen - 1)) 141 v |= AU0828_I2C_TRIGGER_HOLD; 142 auvitek_write_1(sc, AU0828_REG_I2C_TRIGGER, v); 143 144 if (auvitek_i2c_wait_rddone(sc) == false) 145 return EBUSY; 146 147 buf[i] = auvitek_read_1(sc, AU0828_REG_I2C_FIFORD); 148 } 149 150 if (auvitek_i2c_wait(sc) == false) 151 return EBUSY; 152 153 return 0; 154 } 155 156 static int 157 auvitek_i2c_write(struct auvitek_softc *sc, i2c_addr_t addr, 158 const uint8_t *buf, size_t buflen) 159 { 160 uint8_t v; 161 unsigned int i, fifolen; 162 163 //KASSERT(mutex_owned(&sc->sc_i2c_lock)); 164 165 auvitek_write_1(sc, AU0828_REG_I2C_MBMODE, 1); 166 auvitek_write_1(sc, AU0828_REG_I2C_CLKDIV, sc->sc_i2c_clkdiv); 167 auvitek_write_1(sc, AU0828_REG_I2C_DSTADDR, addr << 1); 168 169 if (buflen == 0) { 170 auvitek_write_1(sc, AU0828_REG_I2C_TRIGGER, 171 AU0828_I2C_TRIGGER_RD); 172 if (auvitek_i2c_wait(sc) == false) 173 return EBUSY; 174 if (auvitek_i2c_wait_rdack(sc) == false) 175 return EBUSY; 176 return 0; 177 } 178 179 fifolen = 0; 180 for (i = 0; i < buflen; i++) { 181 v = AU0828_I2C_TRIGGER_WR; 182 if (i < (buflen - 1)) 183 v |= AU0828_I2C_TRIGGER_HOLD; 184 185 auvitek_write_1(sc, AU0828_REG_I2C_FIFOWR, buf[i]); 186 ++fifolen; 187 188 if (fifolen == 4 || i == (buflen - 1)) { 189 auvitek_write_1(sc, AU0828_REG_I2C_TRIGGER, v); 190 fifolen = 0; 191 192 if (auvitek_i2c_wait_wrdone(sc) == false) 193 return EBUSY; 194 } 195 } 196 197 if (auvitek_i2c_wait(sc) == false) 198 return EBUSY; 199 200 return 0; 201 } 202 203 static bool 204 auvitek_i2c_wait(struct auvitek_softc *sc) 205 { 206 uint8_t status; 207 int retry = 1000; 208 209 while (--retry > 0) { 210 status = auvitek_read_1(sc, AU0828_REG_I2C_STATUS); 211 if (!(status & AU0828_I2C_STATUS_BUSY)) 212 break; 213 delay(10); 214 } 215 if (retry == 0) 216 return false; 217 218 return true; 219 } 220 221 static bool 222 auvitek_i2c_wait_rdack(struct auvitek_softc *sc) 223 { 224 uint8_t status; 225 int retry = 1000; 226 227 while (--retry > 0) { 228 status = auvitek_read_1(sc, AU0828_REG_I2C_STATUS); 229 if (!(status & AU0828_I2C_STATUS_NO_RD_ACK)) 230 break; 231 delay(10); 232 } 233 if (retry == 0) 234 return false; 235 236 return true; 237 } 238 239 static bool 240 auvitek_i2c_wait_rddone(struct auvitek_softc *sc) 241 { 242 uint8_t status; 243 int retry = 1000; 244 245 while (--retry > 0) { 246 status = auvitek_read_1(sc, AU0828_REG_I2C_STATUS); 247 if (status & AU0828_I2C_STATUS_RD_DONE) 248 break; 249 delay(10); 250 } 251 if (retry == 0) 252 return false; 253 254 return true; 255 } 256 257 static bool 258 auvitek_i2c_wait_wrdone(struct auvitek_softc *sc) 259 { 260 uint8_t status; 261 int retry = 1000; 262 263 while (--retry > 0) { 264 status = auvitek_read_1(sc, AU0828_REG_I2C_STATUS); 265 if (status & AU0828_I2C_STATUS_WR_DONE) 266 break; 267 delay(10); 268 } 269 if (retry == 0) 270 return false; 271 272 return true; 273 } 274
Indexes created Wed Sep 24 02:09:48 GMT 2025