1 /* $NetBSD: spdmem_i2c.c,v 1.6 2012/09/12 00:36:41 pgoyette Exp $ */ 2 3 /* 4 * Copyright (c) 2007 Nicolas Joly 5 * Copyright (c) 2007 Paul Goyette 6 * Copyright (c) 2007 Tobias Nygren 7 * All rights reserved. 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. The name of the author may not be used to endorse or promote products 18 * derived from this software without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 23 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 24 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 30 * POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33 /* 34 * Serial Presence Detect (SPD) memory identification 35 */ 36 37 #include <sys/cdefs.h> 38 __KERNEL_RCSID(0, "$NetBSD: spdmem_i2c.c,v 1.6 2012/09/12 00:36:41 pgoyette Exp $"); 39 40 #include <sys/param.h> 41 #include <sys/device.h> 42 #include <sys/endian.h> 43 #include <sys/module.h> 44 #include <sys/sysctl.h> 45 #include <machine/bswap.h> 46 47 #include <dev/i2c/i2cvar.h> 48 #include <dev/ic/spdmemreg.h> 49 #include <dev/ic/spdmemvar.h> 50 51 /* Constants for matching i2c bus address */ 52 #define SPDMEM_I2C_ADDRMASK 0x78 53 #define SPDMEM_I2C_ADDR 0x50 54 55 struct spdmem_i2c_softc { 56 struct spdmem_softc sc_base; 57 i2c_tag_t sc_tag; 58 i2c_addr_t sc_addr; 59 }; 60 61 static int spdmem_i2c_match(device_t, cfdata_t, void *); 62 static void spdmem_i2c_attach(device_t, device_t, void *); 63 static int spdmem_i2c_detach(device_t, int); 64 65 CFATTACH_DECL_NEW(spdmem_iic, sizeof(struct spdmem_i2c_softc), 66 spdmem_i2c_match, spdmem_i2c_attach, spdmem_i2c_detach, NULL); 67 68 static uint8_t spdmem_i2c_read(struct spdmem_softc *, uint8_t); 69 70 SYSCTL_SETUP_PROTO(sysctl_spdmem_setup); 71 72 static int 73 spdmem_i2c_match(device_t parent, cfdata_t match, void *aux) 74 { 75 struct i2c_attach_args *ia = aux; 76 struct spdmem_i2c_softc sc; 77 78 if (ia->ia_name) { 79 /* add other names as we find more firmware variations */ 80 if (strcmp(ia->ia_name, "dimm-spd") && 81 strcmp(ia->ia_name, "dimm")) 82 return 0; 83 } 84 85 /* only do this lame test when not using direct config */ 86 if (ia->ia_name == NULL) { 87 if ((ia->ia_addr & SPDMEM_I2C_ADDRMASK) != SPDMEM_I2C_ADDR) 88 return 0; 89 } 90 91 sc.sc_tag = ia->ia_tag; 92 sc.sc_addr = ia->ia_addr; 93 sc.sc_base.sc_read = spdmem_i2c_read; 94 95 return spdmem_common_probe(&sc.sc_base); 96 } 97 98 static void 99 spdmem_i2c_attach(device_t parent, device_t self, void *aux) 100 { 101 struct spdmem_i2c_softc *sc = device_private(self); 102 struct i2c_attach_args *ia = aux; 103 104 sc->sc_tag = ia->ia_tag; 105 sc->sc_addr = ia->ia_addr; 106 sc->sc_base.sc_read = spdmem_i2c_read; 107 108 if (!pmf_device_register(self, NULL, NULL)) 109 aprint_error_dev(self, "couldn't establish power handler\n"); 110 111 spdmem_common_attach(&sc->sc_base, self); 112 } 113 114 static int 115 spdmem_i2c_detach(device_t self, int flags) 116 { 117 struct spdmem_i2c_softc *sc = device_private(self); 118 119 pmf_device_deregister(self); 120 121 return spdmem_common_detach(&sc->sc_base, self); 122 } 123 124 static uint8_t 125 spdmem_i2c_read(struct spdmem_softc *softc, uint8_t reg) 126 { 127 uint8_t val; 128 struct spdmem_i2c_softc *sc = (struct spdmem_i2c_softc *)softc; 129 130 iic_acquire_bus(sc->sc_tag, 0); 131 iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP, sc->sc_addr, ®, 1, 132 &val, 1, 0); 133 iic_release_bus(sc->sc_tag, 0); 134 135 return val; 136 } 137 138 MODULE(MODULE_CLASS_DRIVER, spdmem, "iic"); 139 140 #ifdef _MODULE 141 #include "ioconf.c" 142 #endif 143 144 static int 145 spdmem_modcmd(modcmd_t cmd, void *opaque) 146 { 147 int error = 0; 148 #ifdef _MODULE 149 static struct sysctllog *spdmem_sysctl_clog; 150 #endif 151 152 switch (cmd) { 153 case MODULE_CMD_INIT: 154 #ifdef _MODULE 155 sysctl_spdmem_setup(&spdmem_sysctl_clog); 156 error = config_init_component(cfdriver_ioconf_spdmem, 157 cfattach_ioconf_spdmem, cfdata_ioconf_spdmem); 158 #endif 159 return error; 160 case MODULE_CMD_FINI: 161 #ifdef _MODULE 162 error = config_fini_component(cfdriver_ioconf_spdmem, 163 cfattach_ioconf_spdmem, cfdata_ioconf_spdmem); 164 sysctl_teardown(&spdmem_sysctl_clog); 165 #endif 166 return error; 167 default: 168 return ENOTTY; 169 } 170 } 171