/
i2c.c
670 lines (557 loc) · 14.6 KB
/
i2c.c
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/* $NetBSD: i2c.c,v 1.55 2017/06/01 02:45:10 chs Exp $ */
/*
* Copyright (c) 2003 Wasabi Systems, Inc.
* All rights reserved.
*
* Written by Jason R. Thorpe for Wasabi Systems, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed for the NetBSD Project by
* Wasabi Systems, Inc.
* 4. The name of Wasabi Systems, Inc. may not be used to endorse
* or promote products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL WASABI SYSTEMS, INC
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#ifdef _KERNEL_OPT
#include "opt_i2c.h"
#endif
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: i2c.c,v 1.55 2017/06/01 02:45:10 chs Exp $");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/device.h>
#include <sys/event.h>
#include <sys/conf.h>
#include <sys/malloc.h>
#include <sys/kmem.h>
#include <sys/kthread.h>
#include <sys/proc.h>
#include <sys/kernel.h>
#include <sys/fcntl.h>
#include <sys/module.h>
#include <sys/once.h>
#include <sys/mutex.h>
#include <dev/i2c/i2cvar.h>
#include "locators.h"
#ifndef I2C_MAX_ADDR
#define I2C_MAX_ADDR 0x3ff /* 10-bit address, max */
#endif
struct iic_softc {
i2c_tag_t sc_tag;
int sc_type;
device_t sc_devices[I2C_MAX_ADDR + 1];
};
static dev_type_open(iic_open);
static dev_type_close(iic_close);
static dev_type_ioctl(iic_ioctl);
int iic_init(void);
kmutex_t iic_mtx;
int iic_refcnt;
ONCE_DECL(iic_once);
const struct cdevsw iic_cdevsw = {
.d_open = iic_open,
.d_close = iic_close,
.d_read = noread,
.d_write = nowrite,
.d_ioctl = iic_ioctl,
.d_stop = nostop,
.d_tty = notty,
.d_poll = nopoll,
.d_mmap = nommap,
.d_kqfilter = nokqfilter,
.d_discard = nodiscard,
.d_flag = D_OTHER
};
extern struct cfdriver iic_cd;
static void iic_smbus_intr_thread(void *);
static void iic_fill_compat(struct i2c_attach_args*, const char*,
size_t, char **);
static int
iic_print_direct(void *aux, const char *pnp)
{
struct i2c_attach_args *ia = aux;
if (pnp != NULL)
aprint_normal("%s at %s addr 0x%02x", ia->ia_name, pnp,
ia->ia_addr);
else
aprint_normal(" addr 0x%02x", ia->ia_addr);
return UNCONF;
}
static int
iic_print(void *aux, const char *pnp)
{
struct i2c_attach_args *ia = aux;
if (ia->ia_addr != (i2c_addr_t)-1)
aprint_normal(" addr 0x%x", ia->ia_addr);
return UNCONF;
}
static int
iic_search(device_t parent, cfdata_t cf, const int *ldesc, void *aux)
{
struct iic_softc *sc = device_private(parent);
struct i2c_attach_args ia;
ia.ia_tag = sc->sc_tag;
ia.ia_size = cf->cf_loc[IICCF_SIZE];
ia.ia_type = sc->sc_type;
ia.ia_name = NULL;
ia.ia_ncompat = 0;
ia.ia_compat = NULL;
for (ia.ia_addr = 0; ia.ia_addr <= I2C_MAX_ADDR; ia.ia_addr++) {
if (sc->sc_devices[ia.ia_addr] != NULL)
continue;
if (cf->cf_loc[IICCF_ADDR] != -1 &&
cf->cf_loc[IICCF_ADDR] != ia.ia_addr)
continue;
if (config_match(parent, cf, &ia) > 0)
sc->sc_devices[ia.ia_addr] =
config_attach(parent, cf, &ia, iic_print);
}
return 0;
}
static void
iic_child_detach(device_t parent, device_t child)
{
struct iic_softc *sc = device_private(parent);
int i;
for (i = 0; i <= I2C_MAX_ADDR; i++)
if (sc->sc_devices[i] == child) {
sc->sc_devices[i] = NULL;
break;
}
}
static int
iic_rescan(device_t self, const char *ifattr, const int *locators)
{
config_search_ia(iic_search, self, ifattr, NULL);
return 0;
}
static int
iic_match(device_t parent, cfdata_t cf, void *aux)
{
return 1;
}
static void
iic_attach(device_t parent, device_t self, void *aux)
{
struct iic_softc *sc = device_private(self);
struct i2cbus_attach_args *iba = aux;
prop_array_t child_devices;
prop_dictionary_t props;
char *buf;
i2c_tag_t ic;
int rv;
bool indirect_config;
aprint_naive("\n");
aprint_normal(": I2C bus\n");
sc->sc_tag = iba->iba_tag;
sc->sc_type = iba->iba_type;
ic = sc->sc_tag;
ic->ic_devname = device_xname(self);
LIST_INIT(&(sc->sc_tag->ic_list));
LIST_INIT(&(sc->sc_tag->ic_proc_list));
rv = kthread_create(PRI_NONE, KTHREAD_MUSTJOIN, NULL,
iic_smbus_intr_thread, ic, &ic->ic_intr_thread,
"%s", ic->ic_devname);
if (rv)
aprint_error_dev(self, "unable to create intr thread\n");
if (!pmf_device_register(self, NULL, NULL))
aprint_error_dev(self, "couldn't establish power handler\n");
if (iba->iba_child_devices) {
child_devices = iba->iba_child_devices;
indirect_config = false;
} else {
props = device_properties(parent);
if (!prop_dictionary_get_bool(props, "i2c-indirect-config",
&indirect_config))
indirect_config = true;
child_devices = prop_dictionary_get(props, "i2c-child-devices");
}
if (child_devices) {
unsigned int i, count;
prop_dictionary_t dev;
prop_data_t cdata;
uint32_t addr, size;
uint64_t cookie;
const char *name;
struct i2c_attach_args ia;
int loc[IICCF_NLOCS];
memset(loc, 0, sizeof loc);
count = prop_array_count(child_devices);
for (i = 0; i < count; i++) {
dev = prop_array_get(child_devices, i);
if (!dev) continue;
if (!prop_dictionary_get_cstring_nocopy(
dev, "name", &name))
continue;
if (!prop_dictionary_get_uint32(dev, "addr", &addr))
continue;
if (!prop_dictionary_get_uint64(dev, "cookie", &cookie))
cookie = 0;
loc[IICCF_ADDR] = addr;
if (prop_dictionary_get_uint32(dev, "size", &size))
loc[IICCF_SIZE] = size;
else
size = loc[IICCF_SIZE] = IICCF_SIZE_DEFAULT;
memset(&ia, 0, sizeof ia);
ia.ia_addr = addr;
ia.ia_type = sc->sc_type;
ia.ia_tag = ic;
ia.ia_name = name;
ia.ia_cookie = cookie;
ia.ia_size = size;
buf = NULL;
cdata = prop_dictionary_get(dev, "compatible");
if (cdata)
iic_fill_compat(&ia,
prop_data_data_nocopy(cdata),
prop_data_size(cdata), &buf);
if (addr > I2C_MAX_ADDR) {
aprint_error_dev(self,
"WARNING: ignoring bad device address "
"@ 0x%02x\n", addr);
} else if (sc->sc_devices[addr] == NULL) {
sc->sc_devices[addr] =
config_found_sm_loc(self, "iic", loc, &ia,
iic_print_direct, NULL);
}
if (ia.ia_compat)
free(ia.ia_compat, M_TEMP);
if (buf)
free(buf, M_TEMP);
}
} else if (indirect_config) {
/*
* Attach all i2c devices described in the kernel
* configuration file.
*/
iic_rescan(self, "iic", NULL);
}
}
static int
iic_detach(device_t self, int flags)
{
struct iic_softc *sc = device_private(self);
i2c_tag_t ic = sc->sc_tag;
int i, error;
void *hdl;
for (i = 0; i <= I2C_MAX_ADDR; i++) {
if (sc->sc_devices[i]) {
error = config_detach(sc->sc_devices[i], flags);
if (error)
return error;
}
}
if (ic->ic_running) {
ic->ic_running = 0;
wakeup(ic);
kthread_join(ic->ic_intr_thread);
}
if (!LIST_EMPTY(&ic->ic_list)) {
device_printf(self, "WARNING: intr handler list not empty\n");
while (!LIST_EMPTY(&ic->ic_list)) {
hdl = LIST_FIRST(&ic->ic_list);
iic_smbus_intr_disestablish(ic, hdl);
}
}
if (!LIST_EMPTY(&ic->ic_proc_list)) {
device_printf(self, "WARNING: proc handler list not empty\n");
while (!LIST_EMPTY(&ic->ic_proc_list)) {
hdl = LIST_FIRST(&ic->ic_proc_list);
iic_smbus_intr_disestablish_proc(ic, hdl);
}
}
pmf_device_deregister(self);
return 0;
}
static void
iic_smbus_intr_thread(void *aux)
{
i2c_tag_t ic;
struct ic_intr_list *il;
ic = (i2c_tag_t)aux;
ic->ic_running = 1;
ic->ic_pending = 0;
while (ic->ic_running) {
if (ic->ic_pending == 0)
tsleep(ic, PZERO, "iicintr", hz);
if (ic->ic_pending > 0) {
LIST_FOREACH(il, &(ic->ic_proc_list), il_next) {
(*il->il_intr)(il->il_intrarg);
}
ic->ic_pending--;
}
}
kthread_exit(0);
}
void *
iic_smbus_intr_establish(i2c_tag_t ic, int (*intr)(void *), void *intrarg)
{
struct ic_intr_list *il;
il = malloc(sizeof(struct ic_intr_list), M_DEVBUF, M_WAITOK);
if (il == NULL)
return NULL;
il->il_intr = intr;
il->il_intrarg = intrarg;
LIST_INSERT_HEAD(&(ic->ic_list), il, il_next);
return il;
}
void
iic_smbus_intr_disestablish(i2c_tag_t ic, void *hdl)
{
struct ic_intr_list *il;
il = (struct ic_intr_list *)hdl;
LIST_REMOVE(il, il_next);
free(il, M_DEVBUF);
return;
}
void *
iic_smbus_intr_establish_proc(i2c_tag_t ic, int (*intr)(void *), void *intrarg)
{
struct ic_intr_list *il;
il = malloc(sizeof(struct ic_intr_list), M_DEVBUF, M_WAITOK);
if (il == NULL)
return NULL;
il->il_intr = intr;
il->il_intrarg = intrarg;
LIST_INSERT_HEAD(&(ic->ic_proc_list), il, il_next);
return il;
}
void
iic_smbus_intr_disestablish_proc(i2c_tag_t ic, void *hdl)
{
struct ic_intr_list *il;
il = (struct ic_intr_list *)hdl;
LIST_REMOVE(il, il_next);
free(il, M_DEVBUF);
return;
}
int
iic_smbus_intr(i2c_tag_t ic)
{
struct ic_intr_list *il;
LIST_FOREACH(il, &(ic->ic_list), il_next) {
(*il->il_intr)(il->il_intrarg);
}
ic->ic_pending++;
wakeup(ic);
return 1;
}
static void
iic_fill_compat(struct i2c_attach_args *ia, const char *compat, size_t len,
char **buffer)
{
int count, i;
const char *c, *start, **ptr;
*buffer = NULL;
for (i = count = 0, c = compat; i < len; i++, c++)
if (*c == 0)
count++;
count += 2;
ptr = malloc(sizeof(char*)*count, M_TEMP, M_WAITOK);
if (!ptr) return;
for (i = count = 0, start = c = compat; i < len; i++, c++) {
if (*c == 0) {
ptr[count++] = start;
start = c+1;
}
}
if (start < compat+len) {
/* last string not 0 terminated */
size_t l = c-start;
*buffer = malloc(l+1, M_TEMP, M_WAITOK);
memcpy(*buffer, start, l);
(*buffer)[l] = 0;
ptr[count++] = *buffer;
}
ptr[count] = NULL;
ia->ia_compat = ptr;
ia->ia_ncompat = count;
}
int
iic_compat_match(struct i2c_attach_args *ia, const char ** compats)
{
int i;
for (; compats && *compats; compats++) {
for (i = 0; i < ia->ia_ncompat; i++) {
if (strcmp(*compats, ia->ia_compat[i]) == 0)
return 1;
}
}
return 0;
}
static int
iic_open(dev_t dev, int flag, int fmt, lwp_t *l)
{
struct iic_softc *sc = device_lookup_private(&iic_cd, minor(dev));
mutex_enter(&iic_mtx);
if (sc == NULL) {
mutex_exit(&iic_mtx);
return ENXIO;
}
iic_refcnt++;
mutex_exit(&iic_mtx);
return 0;
}
static int
iic_close(dev_t dev, int flag, int fmt, lwp_t *l)
{
mutex_enter(&iic_mtx);
iic_refcnt--;
mutex_exit(&iic_mtx);
return 0;
}
static int
iic_ioctl_exec(struct iic_softc *sc, i2c_ioctl_exec_t *iie, int flag)
{
i2c_tag_t ic = sc->sc_tag;
uint8_t buf[I2C_EXEC_MAX_BUFLEN];
void *cmd = NULL;
int error;
/* Validate parameters */
if (iie->iie_addr > I2C_MAX_ADDR)
return EINVAL;
if (iie->iie_cmdlen > I2C_EXEC_MAX_CMDLEN ||
iie->iie_buflen > I2C_EXEC_MAX_BUFLEN)
return EINVAL;
if (iie->iie_cmd != NULL && iie->iie_cmdlen == 0)
return EINVAL;
if (iie->iie_buf != NULL && iie->iie_buflen == 0)
return EINVAL;
if (I2C_OP_WRITE_P(iie->iie_op) && (flag & FWRITE) == 0)
return EBADF;
#if 0
/* Disallow userspace access to devices that have drivers attached. */
if (sc->sc_devices[iie->iie_addr] != NULL)
return EBUSY;
#endif
if (iie->iie_cmd != NULL) {
cmd = kmem_alloc(iie->iie_cmdlen, KM_SLEEP);
error = copyin(iie->iie_cmd, cmd, iie->iie_cmdlen);
if (error)
goto out;
}
if (iie->iie_buf != NULL && I2C_OP_WRITE_P(iie->iie_op)) {
error = copyin(iie->iie_buf, buf, iie->iie_buflen);
if (error)
goto out;
}
iic_acquire_bus(ic, 0);
error = iic_exec(ic, iie->iie_op, iie->iie_addr, cmd, iie->iie_cmdlen,
buf, iie->iie_buflen, 0);
iic_release_bus(ic, 0);
/*
* Some drivers return error codes on failure, and others return -1.
*/
if (error < 0)
error = EIO;
out:
if (cmd)
kmem_free(cmd, iie->iie_cmdlen);
if (error)
return error;
if (iie->iie_buf != NULL && I2C_OP_READ_P(iie->iie_op))
error = copyout(buf, iie->iie_buf, iie->iie_buflen);
return error;
}
static int
iic_ioctl(dev_t dev, u_long cmd, void *data, int flag, lwp_t *l)
{
struct iic_softc *sc = device_lookup_private(&iic_cd, minor(dev));
if (sc == NULL)
return ENXIO;
switch (cmd) {
case I2C_IOCTL_EXEC:
return iic_ioctl_exec(sc, (i2c_ioctl_exec_t *)data, flag);
default:
return ENODEV;
}
}
CFATTACH_DECL2_NEW(iic, sizeof(struct iic_softc),
iic_match, iic_attach, iic_detach, NULL, iic_rescan, iic_child_detach);
MODULE(MODULE_CLASS_DRIVER, iic, "i2cexec,i2c_bitbang");
#ifdef _MODULE
#include "ioconf.c"
#endif
int
iic_init(void)
{
mutex_init(&iic_mtx, MUTEX_DEFAULT, IPL_NONE);
iic_refcnt = 0;
return 0;
}
static int
iic_modcmd(modcmd_t cmd, void *opaque)
{
#ifdef _MODULE
int bmajor, cmajor;
#endif
int error;
error = 0;
switch (cmd) {
case MODULE_CMD_INIT:
RUN_ONCE(&iic_once, iic_init);
#ifdef _MODULE
mutex_enter(&iic_mtx);
bmajor = cmajor = -1;
error = devsw_attach("iic", NULL, &bmajor,
&iic_cdevsw, &cmajor);
if (error != 0) {
mutex_exit(&iic_mtx);
break;
}
error = config_init_component(cfdriver_ioconf_iic,
cfattach_ioconf_iic, cfdata_ioconf_iic);
if (error) {
aprint_error("%s: unable to init component\n",
iic_cd.cd_name);
(void)devsw_detach(NULL, &iic_cdevsw);
}
mutex_exit(&iic_mtx);
#endif
break;
case MODULE_CMD_FINI:
mutex_enter(&iic_mtx);
if (iic_refcnt != 0) {
mutex_exit(&iic_mtx);
return EBUSY;
}
#ifdef _MODULE
error = config_fini_component(cfdriver_ioconf_iic,
cfattach_ioconf_iic, cfdata_ioconf_iic);
if (error != 0) {
mutex_exit(&iic_mtx);
break;
}
error = devsw_detach(NULL, &iic_cdevsw);
if (error != 0)
config_init_component(cfdriver_ioconf_iic,
cfattach_ioconf_iic, cfdata_ioconf_iic);
#endif
mutex_exit(&iic_mtx);
break;
default:
error = ENOTTY;
}
return error;
}