spdmem_i2c.c revision 1.12
1/* $NetBSD: spdmem_i2c.c,v 1.12 2016/01/05 11:49:32 msaitoh Exp $ */ 2 3/* 4 * Copyright (c) 2007 Nicolas Joly 5 * Copyright (c) 2007 Paul Goyette 6 * Copyright (c) 2007 Tobias Nygren 7 * Copyright (c) 2015 Michael van Elst 8 * All rights reserved. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. The name of the author may not be used to endorse or promote products 19 * derived from this software without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS 22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 23 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 24 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 25 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 26 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 27 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 28 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 29 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 30 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 31 * POSSIBILITY OF SUCH DAMAGE. 32 */ 33 34/* 35 * Serial Presence Detect (SPD) memory identification 36 * 37 * JEDEC standard No. 21-C 38 * JEDEC document 4_01_06R24 39 * - Definitions of the EE1004-v 4 Kbit Serial Presence Detect EEPROM [...] 40 */ 41 42#include <sys/cdefs.h> 43__KERNEL_RCSID(0, "$NetBSD: spdmem_i2c.c,v 1.12 2016/01/05 11:49:32 msaitoh Exp $"); 44 45#include <sys/param.h> 46#include <sys/device.h> 47#include <sys/endian.h> 48#include <sys/module.h> 49#include <sys/sysctl.h> 50#include <machine/bswap.h> 51 52#include <dev/i2c/i2cvar.h> 53#include <dev/ic/spdmemreg.h> 54#include <dev/ic/spdmemvar.h> 55 56/* Constants for matching i2c bus address */ 57#define SPDMEM_I2C_ADDRMASK 0xfff8 58#define SPDMEM_I2C_ADDR 0x50 59#define SPDCTL_I2C_ADDR 0x30 60 61/* set write protection */ 62#define SPDCTL_SWP0 (SPDCTL_I2C_ADDR + 1) 63#define SPDCTL_SWP1 (SPDCTL_I2C_ADDR + 4) 64#define SPDCTL_SWP2 (SPDCTL_I2C_ADDR + 5) 65#define SPDCTL_SWP3 (SPDCTL_I2C_ADDR + 0) 66 67/* clear write protections */ 68#define SPDCTL_CWP (SPDCTL_I2C_ADDR + 3) 69 70/* read protection status */ 71#define SPDCTL_RPS0 (SPDCTL_I2C_ADDR + 1) 72#define SPDCTL_RPS1 (SPDCTL_I2C_ADDR + 4) 73#define SPDCTL_RPS2 (SPDCTL_I2C_ADDR + 5) 74#define SPDCTL_RPS3 (SPDCTL_I2C_ADDR + 0) 75 76/* select page address */ 77#define SPDCTL_SPA0 (SPDCTL_I2C_ADDR + 6) 78#define SPDCTL_SPA1 (SPDCTL_I2C_ADDR + 7) 79 80/* read page address */ 81#define SPDCTL_RPA (SPDCTL_I2C_ADDR + 6) 82 83struct spdmem_i2c_softc { 84 struct spdmem_softc sc_base; 85 i2c_tag_t sc_tag; 86 i2c_addr_t sc_addr; /* EEPROM */ 87 i2c_addr_t sc_page0; 88 i2c_addr_t sc_page1; 89}; 90 91static int spdmem_i2c_match(device_t, cfdata_t, void *); 92static void spdmem_i2c_attach(device_t, device_t, void *); 93static int spdmem_i2c_detach(device_t, int); 94 95CFATTACH_DECL_NEW(spdmem_iic, sizeof(struct spdmem_i2c_softc), 96 spdmem_i2c_match, spdmem_i2c_attach, spdmem_i2c_detach, NULL); 97 98static int spdmem_i2c_read(struct spdmem_softc *, uint16_t, uint8_t *); 99 100static int 101spdmem_i2c_match(device_t parent, cfdata_t match, void *aux) 102{ 103 struct i2c_attach_args *ia = aux; 104 struct spdmem_i2c_softc sc; 105 106 if (ia->ia_name) { 107 /* add other names as we find more firmware variations */ 108 if (strcmp(ia->ia_name, "dimm-spd") && 109 strcmp(ia->ia_name, "dimm")) 110 return 0; 111 } 112 113 /* only do this lame test when not using direct config */ 114 if (ia->ia_name == NULL) { 115 if ((ia->ia_addr & SPDMEM_I2C_ADDRMASK) != SPDMEM_I2C_ADDR) 116 return 0; 117 } 118 119 sc.sc_tag = ia->ia_tag; 120 sc.sc_addr = ia->ia_addr; 121 sc.sc_page0 = SPDCTL_SPA0; 122 sc.sc_page1 = SPDCTL_SPA1; 123 sc.sc_base.sc_read = spdmem_i2c_read; 124 125 return spdmem_common_probe(&sc.sc_base); 126} 127 128static void 129spdmem_i2c_attach(device_t parent, device_t self, void *aux) 130{ 131 struct spdmem_i2c_softc *sc = device_private(self); 132 struct i2c_attach_args *ia = aux; 133 134 sc->sc_tag = ia->ia_tag; 135 sc->sc_addr = ia->ia_addr; 136 sc->sc_page0 = SPDCTL_SPA0; 137 sc->sc_page1 = SPDCTL_SPA1; 138 sc->sc_base.sc_read = spdmem_i2c_read; 139 140 if (!pmf_device_register(self, NULL, NULL)) 141 aprint_error_dev(self, "couldn't establish power handler\n"); 142 143 spdmem_common_attach(&sc->sc_base, self); 144} 145 146static int 147spdmem_i2c_detach(device_t self, int flags) 148{ 149 struct spdmem_i2c_softc *sc = device_private(self); 150 151 pmf_device_deregister(self); 152 153 return spdmem_common_detach(&sc->sc_base, self); 154} 155 156static int 157spdmem_i2c_read(struct spdmem_softc *softc, uint16_t addr, uint8_t *val) 158{ 159 uint8_t reg; 160 struct spdmem_i2c_softc *sc = (struct spdmem_i2c_softc *)softc; 161 static uint8_t dummy = 0; 162 int rv; 163 164 reg = addr & 0xff; 165 166 iic_acquire_bus(sc->sc_tag, 0); 167 168 if (addr & 0x100) { 169 rv = iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP, sc->sc_page1, 170 &dummy, 1, NULL, 0, I2C_F_POLL); 171 rv |= iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP, sc->sc_addr, 172 ®, 1, val, 1, I2C_F_POLL); 173 rv |= iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP, 174 sc->sc_page0, &dummy, 1, NULL, 0, I2C_F_POLL); 175 } else { 176 rv = iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP, sc->sc_addr, 177 ®, 1, val, 1, I2C_F_POLL); 178 } 179 180 iic_release_bus(sc->sc_tag, 0); 181 182 return rv; 183} 184 185MODULE(MODULE_CLASS_DRIVER, spdmem, "i2cexec"); 186 187#ifdef _MODULE 188#include "ioconf.c" 189#endif 190 191static int 192spdmem_modcmd(modcmd_t cmd, void *opaque) 193{ 194 int error = 0; 195#ifdef _MODULE 196 static struct sysctllog *spdmem_sysctl_clog; 197#endif 198 199 switch (cmd) { 200 case MODULE_CMD_INIT: 201#ifdef _MODULE 202 error = config_init_component(cfdriver_ioconf_spdmem, 203 cfattach_ioconf_spdmem, cfdata_ioconf_spdmem); 204#endif 205 return error; 206 case MODULE_CMD_FINI: 207#ifdef _MODULE 208 error = config_fini_component(cfdriver_ioconf_spdmem, 209 cfattach_ioconf_spdmem, cfdata_ioconf_spdmem); 210 sysctl_teardown(&spdmem_sysctl_clog); 211#endif 212 return error; 213 default: 214 return ENOTTY; 215 } 216} 217