iicbus.c revision 227843
138774Snsouch/*- 293023Snsouch * Copyright (c) 1998, 2001 Nicolas Souchu 338774Snsouch * All rights reserved. 438774Snsouch * 538774Snsouch * Redistribution and use in source and binary forms, with or without 638774Snsouch * modification, are permitted provided that the following conditions 738774Snsouch * are met: 838774Snsouch * 1. Redistributions of source code must retain the above copyright 938774Snsouch * notice, this list of conditions and the following disclaimer. 1038774Snsouch * 2. Redistributions in binary form must reproduce the above copyright 1138774Snsouch * notice, this list of conditions and the following disclaimer in the 1238774Snsouch * documentation and/or other materials provided with the distribution. 1338774Snsouch * 1438774Snsouch * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 1538774Snsouch * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 1638774Snsouch * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 1738774Snsouch * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 1838774Snsouch * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 1938774Snsouch * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 2038774Snsouch * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 2138774Snsouch * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 2238774Snsouch * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 2338774Snsouch * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 2438774Snsouch * SUCH DAMAGE. 2538774Snsouch */ 2638774Snsouch 27119418Sobrien#include <sys/cdefs.h> 28119418Sobrien__FBSDID("$FreeBSD: head/sys/dev/iicbus/iicbus.c 227843 2011-11-22 21:28:20Z marius $"); 29119418Sobrien 3038774Snsouch/* 3138774Snsouch * Autoconfiguration and support routines for the Philips serial I2C bus 3238774Snsouch */ 3338774Snsouch 3438774Snsouch#include <sys/param.h> 3538774Snsouch#include <sys/systm.h> 3638774Snsouch#include <sys/kernel.h> 37181304Sjhb#include <sys/lock.h> 38167856Simp#include <sys/malloc.h> 3938774Snsouch#include <sys/module.h> 40181304Sjhb#include <sys/mutex.h> 4138774Snsouch#include <sys/bus.h> 4238774Snsouch 4338774Snsouch#include <dev/iicbus/iiconf.h> 4438774Snsouch#include <dev/iicbus/iicbus.h> 4538774Snsouch 4638774Snsouch#include "iicbus_if.h" 4738774Snsouch 48129152Sjoerg/* See comments below for why auto-scanning is a bad idea. */ 49129152Sjoerg#define SCAN_IICBUS 0 50129152Sjoerg 5140782Snsouchstatic int 5240782Snsouchiicbus_probe(device_t dev) 5340782Snsouch{ 54160372Simp 5542442Snsouch device_set_desc(dev, "Philips I2C bus"); 56186833Snwhitehorn 57186833Snwhitehorn /* Allow other subclasses to override this driver. */ 58187457Snwhitehorn return (BUS_PROBE_GENERIC); 5940782Snsouch} 6040782Snsouch 61129152Sjoerg#if SCAN_IICBUS 6240782Snsouchstatic int 6340782Snsouchiic_probe_device(device_t dev, u_char addr) 6440782Snsouch{ 6540782Snsouch int count; 6640782Snsouch char byte; 6740782Snsouch 6840782Snsouch if ((addr & 1) == 0) { 6940782Snsouch /* is device writable? */ 7040782Snsouch if (!iicbus_start(dev, (u_char)addr, 0)) { 7140782Snsouch iicbus_stop(dev); 7240782Snsouch return (1); 7340782Snsouch } 7440782Snsouch } else { 7540782Snsouch /* is device readable? */ 7640782Snsouch if (!iicbus_block_read(dev, (u_char)addr, &byte, 1, &count)) 7740782Snsouch return (1); 7840782Snsouch } 7940782Snsouch 8040782Snsouch return (0); 8140782Snsouch} 8242442Snsouch#endif 8340782Snsouch 8438774Snsouch/* 8540782Snsouch * We add all the devices which we know about. 8640782Snsouch * The generic attach routine will attach them if they are alive. 8738774Snsouch */ 8838774Snsouchstatic int 8940782Snsouchiicbus_attach(device_t dev) 9038774Snsouch{ 91129152Sjoerg#if SCAN_IICBUS 92129152Sjoerg unsigned char addr; 93129152Sjoerg#endif 94167856Simp struct iicbus_softc *sc = IICBUS_SOFTC(dev); 95129152Sjoerg 96167856Simp sc->dev = dev; 97181304Sjhb mtx_init(&sc->lock, "iicbus", NULL, MTX_DEF); 9840782Snsouch iicbus_reset(dev, IIC_FASTEST, 0, NULL); 9938774Snsouch 10042442Snsouch /* device probing is meaningless since the bus is supposed to be 10142442Snsouch * hot-plug. Moreover, some I2C chips do not appreciate random 10242442Snsouch * accesses like stop after start to fast, reads for less than 10342442Snsouch * x bytes... 10442442Snsouch */ 105129152Sjoerg#if SCAN_IICBUS 10640782Snsouch printf("Probing for devices on iicbus%d:", device_get_unit(dev)); 10738774Snsouch 10840782Snsouch /* probe any devices */ 109129152Sjoerg for (addr = 16; addr < 240; addr++) { 11040782Snsouch if (iic_probe_device(dev, (u_char)addr)) { 11140782Snsouch printf(" <%x>", addr); 11240782Snsouch } 11340782Snsouch } 11440782Snsouch printf("\n"); 11542442Snsouch#endif 116181304Sjhb bus_generic_probe(dev); 117167856Simp bus_enumerate_hinted_children(dev); 11838774Snsouch bus_generic_attach(dev); 11938774Snsouch return (0); 12038774Snsouch} 12193023Snsouch 12293023Snsouchstatic int 12393023Snsouchiicbus_detach(device_t dev) 12493023Snsouch{ 125181304Sjhb struct iicbus_softc *sc = IICBUS_SOFTC(dev); 126160372Simp 12793023Snsouch iicbus_reset(dev, IIC_FASTEST, 0, NULL); 12893023Snsouch bus_generic_detach(dev); 129181304Sjhb mtx_destroy(&sc->lock); 13093023Snsouch return (0); 13193023Snsouch} 13293023Snsouch 13393023Snsouchstatic int 134167856Simpiicbus_print_child(device_t dev, device_t child) 13593023Snsouch{ 136167856Simp struct iicbus_ivar *devi = IICBUS_IVAR(child); 137167856Simp int retval = 0; 138160372Simp 139167856Simp retval += bus_print_child_header(dev, child); 140167856Simp if (devi->addr != 0) 141167856Simp retval += printf(" at addr %#x", devi->addr); 142167856Simp retval += bus_print_child_footer(dev, child); 143167856Simp 144167856Simp return (retval); 145167856Simp} 146167856Simp 147167856Simpstatic void 148167856Simpiicbus_probe_nomatch(device_t bus, device_t child) 149167856Simp{ 150167856Simp struct iicbus_ivar *devi = IICBUS_IVAR(child); 151167856Simp 152167856Simp device_printf(bus, "<unknown card>"); 153167856Simp printf(" at addr %#x\n", devi->addr); 154167856Simp return; 155167856Simp} 156167856Simp 157167856Simpstatic int 158167856Simpiicbus_child_location_str(device_t bus, device_t child, char *buf, 159167856Simp size_t buflen) 160167856Simp{ 161167856Simp struct iicbus_ivar *devi = IICBUS_IVAR(child); 162167856Simp 163167856Simp snprintf(buf, buflen, "addr=%#x", devi->addr); 16493023Snsouch return (0); 16593023Snsouch} 16693023Snsouch 167167856Simpstatic int 168167856Simpiicbus_child_pnpinfo_str(device_t bus, device_t child, char *buf, 169167856Simp size_t buflen) 170167856Simp{ 171167856Simp *buf = '\0'; 172167856Simp return (0); 173167856Simp} 174167856Simp 175167856Simpstatic int 176188461Simpiicbus_read_ivar(device_t bus, device_t child, int which, uintptr_t *result) 177167856Simp{ 178167856Simp struct iicbus_ivar *devi = IICBUS_IVAR(child); 179167856Simp 180167856Simp switch (which) { 181167856Simp default: 182167856Simp return (EINVAL); 183167856Simp case IICBUS_IVAR_ADDR: 184209800Snwhitehorn *result = devi->addr; 185167856Simp break; 186167856Simp } 187167856Simp return (0); 188167856Simp} 189167856Simp 190167856Simpstatic device_t 191212413Savgiicbus_add_child(device_t dev, u_int order, const char *name, int unit) 192167856Simp{ 193167856Simp device_t child; 194167856Simp struct iicbus_ivar *devi; 195167856Simp 196167856Simp child = device_add_child_ordered(dev, order, name, unit); 197167856Simp if (child == NULL) 198167856Simp return (child); 199167856Simp devi = malloc(sizeof(struct iicbus_ivar), M_DEVBUF, M_NOWAIT | M_ZERO); 200167856Simp if (devi == NULL) { 201167856Simp device_delete_child(dev, child); 202167856Simp return (0); 203167856Simp } 204167856Simp device_set_ivars(child, devi); 205167856Simp return (child); 206167856Simp} 207167856Simp 208167856Simpstatic void 209167856Simpiicbus_hinted_child(device_t bus, const char *dname, int dunit) 210167856Simp{ 211167856Simp device_t child; 212167856Simp struct iicbus_ivar *devi; 213167856Simp 214167856Simp child = BUS_ADD_CHILD(bus, 0, dname, dunit); 215167856Simp devi = IICBUS_IVAR(child); 216167856Simp resource_int_value(dname, dunit, "addr", &devi->addr); 217167856Simp} 218167856Simp 21938774Snsouchint 22038774Snsouchiicbus_generic_intr(device_t dev, int event, char *buf) 22138774Snsouch{ 222160372Simp 22338774Snsouch return (0); 22438774Snsouch} 22538774Snsouch 22640782Snsouchint 22740782Snsouchiicbus_null_callback(device_t dev, int index, caddr_t data) 22840782Snsouch{ 229160372Simp 23040782Snsouch return (0); 23140782Snsouch} 23240782Snsouch 23340782Snsouchint 23440782Snsouchiicbus_null_repeated_start(device_t dev, u_char addr) 23540782Snsouch{ 236160372Simp 23740782Snsouch return (IIC_ENOTSUPP); 23840782Snsouch} 23940782Snsouch 240167856Simpstatic device_method_t iicbus_methods[] = { 241167856Simp /* device interface */ 242167856Simp DEVMETHOD(device_probe, iicbus_probe), 243167856Simp DEVMETHOD(device_attach, iicbus_attach), 244167856Simp DEVMETHOD(device_detach, iicbus_detach), 245167856Simp 246167856Simp /* bus interface */ 247167856Simp DEVMETHOD(bus_add_child, iicbus_add_child), 248167856Simp DEVMETHOD(bus_print_child, iicbus_print_child), 249167856Simp DEVMETHOD(bus_probe_nomatch, iicbus_probe_nomatch), 250167856Simp DEVMETHOD(bus_read_ivar, iicbus_read_ivar), 251167856Simp DEVMETHOD(bus_child_pnpinfo_str, iicbus_child_pnpinfo_str), 252167856Simp DEVMETHOD(bus_child_location_str, iicbus_child_location_str), 253167856Simp DEVMETHOD(bus_hinted_child, iicbus_hinted_child), 254167856Simp 255167856Simp /* iicbus interface */ 256167856Simp DEVMETHOD(iicbus_transfer, iicbus_transfer), 257167856Simp 258227843Smarius DEVMETHOD_END 259167856Simp}; 260167856Simp 261167856Simpdriver_t iicbus_driver = { 262167856Simp "iicbus", 263167856Simp iicbus_methods, 264167856Simp sizeof(struct iicbus_softc), 265167856Simp}; 266167856Simp 267167856Simpdevclass_t iicbus_devclass; 268167856Simp 26993023SnsouchMODULE_VERSION(iicbus, IICBUS_MODVER); 270187261SnwhitehornDRIVER_MODULE(iicbus, iichb, iicbus_driver, iicbus_devclass, 0, 0); 271187261Snwhitehorn 272