cat24c256: driver for the cat24c256 i2c eeprom

Change-Id: I682d136c80fc868d3f0a5edb0cf6c33c0f3a28ea
This commit is contained in:
Thomas Cort 2013-07-15 10:29:31 -04:00
parent 8a643e5128
commit 526eb34144
8 changed files with 593 additions and 3 deletions

View file

@ -24,7 +24,13 @@ case $#:$1 in
ttyq0 ttyq1 ttyq2 ttyq3 ttyq4 ttyq5 ttyq6 ttyq7 ttyq8 ttyq9 \
ttyqa ttyqb ttyqc ttyqd ttyqe ttyqf \
eth klog random uds filter fbd hello fb0 \
i2c-1 i2c-2 i2c-3
i2c-1 i2c-2 i2c-3 \
eepromb1s50 eepromb1s51 eepromb1s52 eepromb1s53 \
eepromb1s54 eepromb1s55 eepromb1s56 eepromb1s57 \
eepromb2s50 eepromb2s51 eepromb2s52 eepromb2s53 \
eepromb2s54 eepromb2s55 eepromb2s56 eepromb2s57 \
eepromb3s50 eepromb3s51 eepromb3s52 eepromb3s53 \
eepromb3s54 eepromb3s55 eepromb3s56 eepromb3s57
;;
0:|1:-\?)
cat >&2 <<EOF
@ -293,6 +299,14 @@ do
$e mknod i2c-${b} c 2${m} 0
$e chmod 600 i2c-${b}
;;
eepromb[1-3]s5[0-7])
# cat24c256 driver
b=`expr $dev : 'eepromb\\(.*\\)s'` # bus number
s=`expr $dev : 'eepromb.s5\\(.*\\)'` # configurable part of slave addr
m=`expr ${b} \* 8 + ${s} + 17`
$e mknod eepromb${b}s5${s} b ${m} 0
$e chmod 600 eepromb${b}s5${s}
;;
*)
echo "$0: don't know about $dev" >&2
ex=1

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@ -102,6 +102,7 @@
./usr/lib/libpadconf.a minix-sys
./usr/lib/libpadconf_pic.a minix-sys
./usr/mdec minix-sys
./usr/sbin/cat24c256 minix-sys
./usr/sbin/fb minix-sys
./usr/sbin/gpio minix-sys
./usr/sbin/i2c minix-sys

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@ -23,7 +23,7 @@ SUBDIR= ahci amddev atl2 at_wini audio dec21140A dp8390 dpeth \
.endif
.if ${MACHINE_ARCH} == "earm"
SUBDIR= fb gpio i2c mmc log tty random
SUBDIR= cat24c256 fb gpio i2c mmc log tty random
.endif
.endif # ${MKIMAGEONLY} != "yes"

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@ -0,0 +1,14 @@
# Makefile for the i2c eeprom commonly found on the BeagleBone (CAT24C256)
PROG= cat24c256
SRCS= cat24c256.c
DPADD+= ${LIBI2CDRIVER} ${LIBBLOCKDRIVER} ${LIBSYS} ${LIBTIMERS}
LDADD+= -li2cdriver -lblockdriver -lsys -ltimers
MAN=
BINDIR?= /usr/sbin
CPPFLAGS+= -I${NETBSDSRCDIR}
.include <minix.service.mk>

View file

@ -0,0 +1,16 @@
CAT24C256 Driver (EEPROM)
=========================
Overview
--------
This is the driver for the EEPROM chip commonly found on the BeagleBone
and the BeagleBone Black as well as capes and expansion boards.
Testing the Code
----------------
Starting up an instance:
/bin/service up /usr/sbin/cat24c256 -dev /dev/eepromb1s50 -label cat24c256.1.50 -args 'bus=1 address=0x50'

View file

@ -0,0 +1,517 @@
#include <minix/blockdriver.h>
#include <minix/drivers.h>
#include <minix/ds.h>
#include <minix/i2c.h>
#include <minix/i2cdriver.h>
#include <minix/log.h>
#include <stdio.h>
#include <stdlib.h>
/* constants */
#define NR_DEVS 1 /* number of devices this driver handles */
#define EEPROM_DEV 0 /* index of eeprom device */
/* When passing data over a grant one needs to pass
* a buffer to sys_safecopy copybuff is used for that*/
#define COPYBUF_SIZE 0x1000 /* 4k buff */
static unsigned char copybuf[COPYBUF_SIZE];
static i2c_addr_t valid_addrs[9] = {
0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, 0x00
};
/* SEF functions and variables. */
static void sef_local_startup(void);
static int sef_cb_init(int type, sef_init_info_t * info);
static int sef_cb_lu_state_save(int);
static int lu_state_restore(void);
/* libblockdriver callbacks */
static int cat24c256_blk_open(dev_t minor, int access);
static int cat24c256_blk_close(dev_t minor);
static ssize_t cat24c256_blk_transfer(dev_t minor, int do_write, u64_t pos,
endpoint_t endpt, iovec_t * iov, unsigned count, int flags);
static int cat24c256_blk_ioctl(dev_t minor, unsigned int request,
endpoint_t endpt, cp_grant_id_t grant);
static struct device *cat24c256_blk_part(dev_t minor);
static int cat24c256_blk_other(message * m);
/* Entry points into the device dependent code of block drivers. */
struct blockdriver cat24c256_tab = {
.bdr_type = BLOCKDRIVER_TYPE_OTHER,
.bdr_open = cat24c256_blk_open,
.bdr_close = cat24c256_blk_close,
.bdr_transfer = cat24c256_blk_transfer,
.bdr_ioctl = cat24c256_blk_ioctl, /* nop -- always returns EINVAL */
.bdr_cleanup = NULL, /* nothing allocated -- nothing to clean up */
.bdr_part = cat24c256_blk_part,
.bdr_geometry = NULL, /* no geometry (cylinders, heads, sectors, etc) */
.bdr_intr = NULL, /* i2c devices don't generate interrupts */
.bdr_alarm = NULL, /* alarm not needed */
.bdr_other = cat24c256_blk_other, /* to recv notify events from DS */
.bdr_device = NULL /* 1 insance per bus, threads not needed */
};
static int cat24c256_read32(uint16_t memaddr, void *buf, size_t buflen);
static int cat24c256_read(uint16_t memaddr, void *buf, size_t buflen);
static int cat24c256_write16(uint16_t memaddr, void *buf, size_t buflen);
static int cat24c256_write(uint16_t memaddr, void *buf, size_t buflen);
/* globals */
/* counts the number of times a device file is open */
static int openct[NR_DEVS];
/* base and size of each device */
static struct device geom[NR_DEVS];
/* the bus that this device is on (counting starting at 1) */
static uint32_t bus;
/* slave address of the device */
static i2c_addr_t address;
/* endpoint for the driver for the bus itself. */
static endpoint_t bus_endpoint;
/* logging - use with log_warn(), log_info(), log_debug(), log_trace(), etc */
static struct log log = {
.name = "cat24c256",
.log_level = LEVEL_INFO,
.log_func = default_log
};
static int
cat24c256_blk_open(dev_t minor, int access)
{
log_trace(&log, "cat24c256_blk_open(%d,%d)\n", minor, access);
if (cat24c256_blk_part(minor) == NULL) {
return ENXIO;
}
openct[minor]++;
return OK;
}
static int
cat24c256_blk_close(dev_t minor)
{
log_trace(&log, "cat24c256_blk_close(%d)\n", minor);
if (cat24c256_blk_part(minor) == NULL) {
return ENXIO;
}
if (openct[minor] < 1) {
log_warn(&log, "closing unopened device %d\n", minor);
return EINVAL;
}
openct[minor]--;
return OK;
}
static ssize_t
cat24c256_blk_transfer(dev_t minor, int do_write, u64_t pos64,
endpoint_t endpt, iovec_t * iov, unsigned nr_req, int flags)
{
/* Read or write one the driver's block devices. */
unsigned count;
struct device *dv;
u64_t dv_size;
int r;
u64_t position;
cp_grant_id_t grant;
ssize_t total = 0;
vir_bytes offset;
log_trace(&log, "cat24c256_blk_transfer()\n");
/* Get minor device information. */
dv = cat24c256_blk_part(minor);
if (dv == NULL) {
return ENXIO;
}
if (nr_req > NR_IOREQS) {
return EINVAL;
}
dv_size = dv->dv_size;
if (pos64 > dv_size) {
return OK; /* Beyond EOF */
}
position = pos64;
offset = 0;
while (nr_req > 0) {
/* How much to transfer and where to / from. */
count = iov->iov_size;
grant = (cp_grant_id_t) iov->iov_addr;
/* check for EOF */
if (position >= dv_size) {
return total;
}
/* don't go past the end of the device */
if (position + count > dv_size) {
count = dv_size - position;
}
/* don't overflow copybuf */
if (count > COPYBUF_SIZE) {
count = COPYBUF_SIZE;
}
log_trace(&log, "transfering 0x%x bytes\n", count);
if (do_write) {
r = sys_safecopyfrom(endpt, grant, (vir_bytes) offset,
(vir_bytes) copybuf, count);
if (r != OK) {
log_warn(&log, "safecopyfrom failed\n");
return EINVAL;
}
r = cat24c256_write(position, copybuf, count);
if (r != OK) {
log_warn(&log, "write failed (r=%d)\n", r);
return r;
}
} else {
r = cat24c256_read(position, copybuf, count);
if (r != OK) {
log_warn(&log, "read failed (r=%d)\n", r);
return r;
}
r = sys_safecopyto(endpt, grant, (vir_bytes) offset,
(vir_bytes) copybuf, count);
if (r != OK) {
log_warn(&log, "safecopyto failed\n");
return EINVAL;
}
}
/* Book the number of bytes transferred. */
position += count;
total += count;
offset += count;
/* only go on to the next iov when this one is full */
if ((iov->iov_size -= count) == 0) {
iov++;
nr_req--;
offset = 0;
}
}
return total;
}
static int
cat24c256_blk_ioctl(dev_t minor, unsigned int request, endpoint_t endpt,
cp_grant_id_t grant)
{
log_trace(&log, "cat24c256_blk_ioctl(%d)\n", minor);
/* no supported ioctls for this device */
return EINVAL;
}
static struct device *
cat24c256_blk_part(dev_t minor)
{
log_trace(&log, "cat24c256_blk_part(%d)\n", minor);
if (minor >= NR_DEVS) {
return NULL;
}
return &geom[minor];
}
static int
cat24c256_blk_other(message * m)
{
int r;
log_trace(&log, "cat24c256_blk_other(0x%x)\n", m->m_type);
switch (m->m_type) {
case NOTIFY_MESSAGE:
if (m->m_source == DS_PROC_NR) {
log_debug(&log,
"bus driver changed state, update endpoint\n");
i2cdriver_handle_bus_update(&bus_endpoint, bus,
address);
}
r = OK;
break;
default:
log_warn(&log, "Invalid message type (0x%x)\n", m->m_type);
r = EINVAL;
break;
}
return r;
}
/* The lower level i2c interface can only read/write 32 bytes at a time.
* One might want to do more I/O than that at once w/EEPROM, so there is
* cat24c256_read() and cat24c256_read32(). cat24c256_read32() does the
* actual reading in chunks up to 32 bytes. cat24c256_read() splits
* the request up into chunks and repeatedly calls cat24c256_read32()
* until all of the requested EEPROM locations have been read.
*/
static int
cat24c256_read32(uint16_t memaddr, void *buf, size_t buflen)
{
int r;
minix_i2c_ioctl_exec_t ioctl_exec;
if (buflen > I2C_EXEC_MAX_BUFLEN || buf == NULL
|| (((uint16_t) (memaddr + buflen)) < memaddr)) {
log_warn(&log,
"buflen exceeded max or buf == NULL or would overflow\n");
return -1;
}
memset(&ioctl_exec, '\0', sizeof(minix_i2c_ioctl_exec_t));
ioctl_exec.iie_op = I2C_OP_READ_WITH_STOP;
ioctl_exec.iie_addr = address;
/* set the memory address to read from */
ioctl_exec.iie_cmd[0] = ((memaddr >> 8) & 0xff);
ioctl_exec.iie_cmd[1] = (memaddr & 0xff);
ioctl_exec.iie_cmdlen = 2;
ioctl_exec.iie_buflen = buflen;
r = i2cdriver_exec(bus_endpoint, &ioctl_exec);
if (r != OK) {
return r;
}
/* call was good, copy results to caller's buffer */
memcpy(buf, ioctl_exec.iie_buf, buflen);
log_debug(&log, "Read %d bytes from 0x%x 0x%x OK\n", buflen,
ioctl_exec.iie_cmd[0], ioctl_exec.iie_cmd[1]);
return OK;
}
int
cat24c256_read(uint16_t memaddr, void *buf, size_t buflen)
{
int r;
uint16_t i;
if (buf == NULL || ((memaddr + buflen) < memaddr)) {
log_warn(&log, "buf == NULL or would overflow\n");
return -1;
}
for (i = 0; i < buflen; i += 32) {
r = cat24c256_read32(memaddr + i, buf + i,
((buflen - i) < 32) ? (buflen - i) : 32);
if (r != OK) {
return r;
}
log_trace(&log, "read %d bytes starting at 0x%x\n",
((buflen - i) < 32) ? (buflen - i) : 32, memaddr + i);
}
return OK;
}
static int
cat24c256_write16(uint16_t memaddr, void *buf, size_t buflen)
{
int r;
minix_i2c_ioctl_exec_t ioctl_exec;
if (buflen > (I2C_EXEC_MAX_BUFLEN - 2) || buf == NULL
|| (((uint16_t) (memaddr + buflen + 2)) < memaddr)) {
log_warn(&log,
"buflen exceeded max or buf == NULL or would overflow\n");
return -1;
}
memset(&ioctl_exec, '\0', sizeof(minix_i2c_ioctl_exec_t));
ioctl_exec.iie_op = I2C_OP_WRITE_WITH_STOP;
ioctl_exec.iie_addr = address;
ioctl_exec.iie_cmdlen = 0;
/* set the memory address to write to */
ioctl_exec.iie_buf[0] = ((memaddr >> 8) & 0xff);
ioctl_exec.iie_buf[1] = (memaddr & 0xff);
memcpy(ioctl_exec.iie_buf + 2, buf, buflen);
ioctl_exec.iie_buflen = buflen + 2;
r = i2cdriver_exec(bus_endpoint, &ioctl_exec);
if (r != OK) {
return r;
}
log_debug(&log, "Wrote %d bytes to 0x%x 0x%x OK - First = 0x%x\n",
buflen, ioctl_exec.iie_buf[0], ioctl_exec.iie_buf[1],
ioctl_exec.iie_buf[2]);
return OK;
}
int
cat24c256_write(uint16_t memaddr, void *buf, size_t buflen)
{
int r;
uint16_t i;
if (buf == NULL || ((memaddr + buflen) < memaddr)) {
log_warn(&log, "buf == NULL or would overflow\n");
return -1;
}
for (i = 0; i < buflen; i += 16) {
r = cat24c256_write16(memaddr + i, buf + i,
((buflen - i) < 16) ? (buflen - i) : 16);
if (r != OK) {
return r;
}
log_trace(&log, "wrote %d bytes starting at 0x%x\n",
((buflen - i) < 16) ? (buflen - i) : 16, memaddr + i);
}
return OK;
}
static int
sef_cb_lu_state_save(int UNUSED(state))
{
ds_publish_u32("bus", bus, DSF_OVERWRITE);
ds_publish_u32("address", address, DSF_OVERWRITE);
return OK;
}
static int
lu_state_restore(void)
{
/* Restore the state. */
u32_t value;
ds_retrieve_u32("bus", &value);
ds_delete_u32("bus");
bus = (int) value;
ds_retrieve_u32("address", &value);
ds_delete_u32("address");
address = (int) value;
return OK;
}
static int
sef_cb_init(int type, sef_init_info_t * UNUSED(info))
{
int r;
if (type == SEF_INIT_LU) {
/* Restore the state. */
lu_state_restore();
}
geom[EEPROM_DEV].dv_base = ((u64_t) (0));
geom[EEPROM_DEV].dv_size = ((u64_t) (32768));
/* look-up the endpoint for the bus driver */
bus_endpoint = i2cdriver_bus_endpoint(bus);
if (bus_endpoint == 0) {
log_warn(&log, "Couldn't find bus driver.\n");
return EXIT_FAILURE;
}
/* claim the EEPROM device */
r = i2cdriver_reserve_device(bus_endpoint, address);
if (r != OK) {
log_warn(&log, "Couldn't reserve device 0x%x (r=%d)\n",
address, r);
return EXIT_FAILURE;
}
if (type != SEF_INIT_LU) {
/* sign up for updates about the i2c bus going down/up */
r = i2cdriver_subscribe_bus_updates(bus);
if (r != OK) {
log_warn(&log, "Couldn't subscribe to bus updates\n");
return EXIT_FAILURE;
}
i2cdriver_announce(bus);
blockdriver_announce(type);
log_debug(&log, "announced\n");
}
return OK;
}
static void
sef_local_startup(void)
{
/*
* Register init callbacks. Use the same function for all event types
*/
sef_setcb_init_fresh(sef_cb_init);
sef_setcb_init_lu(sef_cb_init);
sef_setcb_init_restart(sef_cb_init);
/*
* Register live update callbacks.
*/
/* Agree to update immediately when LU is requested in a valid state. */
sef_setcb_lu_prepare(sef_cb_lu_prepare_always_ready);
/* Support live update starting from any standard state. */
sef_setcb_lu_state_isvalid(sef_cb_lu_state_isvalid_standard);
/* Register a custom routine to save the state. */
sef_setcb_lu_state_save(sef_cb_lu_state_save);
/* Let SEF perform startup. */
sef_startup();
}
int
main(int argc, char *argv[])
{
int r;
env_setargs(argc, argv);
r = i2cdriver_env_parse(&bus, &address, valid_addrs);
if (r < 0) {
log_warn(&log, "Expecting -args 'bus=X address=0xYY'\n");
log_warn(&log, "Example -args 'bus=3 address=0x54'\n");
return EXIT_FAILURE;
} else if (r > 0) {
log_warn(&log,
"Invalid slave address for device, expecting 0x50-0x57\n");
return EXIT_FAILURE;
}
sef_local_startup();
log_debug(&log, "Startup Complete\n");
blockdriver_task(&cat24c256_tab);
log_debug(&log, "Shutting down\n");
return OK;
}

View file

@ -608,6 +608,11 @@ service i2c
ipc SYSTEM RS DS;
};
service cat24c256
{
ipc SYSTEM RS DS i2c;
};
service vbox
{
system

View file

@ -42,7 +42,30 @@ enum dev_style { STYLE_NDEV, STYLE_DEV, STYLE_DEVA, STYLE_TTY, STYLE_CTTY,
#define I2C0_MAJOR 20 /* 20 = /dev/i2c-1 (i2c-dev) */
#define I2C1_MAJOR 21 /* 21 = /dev/i2c-2 (i2c-dev) */
#define I2C2_MAJOR 22 /* 22 = /dev/i2c-3 (i2c-dev) */
#define EEPROMB1S50_MAJOR 23 /* 23 = /dev/eepromb1s50 (cat24c256) */
#define EEPROMB1S51_MAJOR 24 /* 24 = /dev/eepromb1s51 (cat24c256) */
#define EEPROMB1S52_MAJOR 25 /* 25 = /dev/eepromb1s52 (cat24c256) */
#define EEPROMB1S53_MAJOR 26 /* 26 = /dev/eepromb1s53 (cat24c256) */
#define EEPROMB1S54_MAJOR 27 /* 27 = /dev/eepromb1s54 (cat24c256) */
#define EEPROMB1S55_MAJOR 28 /* 28 = /dev/eepromb1s55 (cat24c256) */
#define EEPROMB1S56_MAJOR 29 /* 29 = /dev/eepromb1s56 (cat24c256) */
#define EEPROMB1S57_MAJOR 30 /* 30 = /dev/eepromb1s57 (cat24c256) */
#define EEPROMB2S50_MAJOR 31 /* 31 = /dev/eepromb2s50 (cat24c256) */
#define EEPROMB2S51_MAJOR 32 /* 32 = /dev/eepromb2s51 (cat24c256) */
#define EEPROMB2S52_MAJOR 33 /* 33 = /dev/eepromb2s52 (cat24c256) */
#define EEPROMB2S53_MAJOR 34 /* 34 = /dev/eepromb2s53 (cat24c256) */
#define EEPROMB2S54_MAJOR 35 /* 35 = /dev/eepromb2s54 (cat24c256) */
#define EEPROMB2S55_MAJOR 36 /* 36 = /dev/eepromb2s55 (cat24c256) */
#define EEPROMB2S56_MAJOR 37 /* 37 = /dev/eepromb2s56 (cat24c256) */
#define EEPROMB2S57_MAJOR 38 /* 38 = /dev/eepromb2s57 (cat24c256) */
#define EEPROMB3S50_MAJOR 39 /* 39 = /dev/eepromb3s50 (cat24c256) */
#define EEPROMB3S51_MAJOR 40 /* 40 = /dev/eepromb3s51 (cat24c256) */
#define EEPROMB3S52_MAJOR 41 /* 41 = /dev/eepromb3s52 (cat24c256) */
#define EEPROMB3S53_MAJOR 42 /* 42 = /dev/eepromb3s53 (cat24c256) */
#define EEPROMB3S54_MAJOR 43 /* 43 = /dev/eepromb3s54 (cat24c256) */
#define EEPROMB3S55_MAJOR 44 /* 44 = /dev/eepromb3s55 (cat24c256) */
#define EEPROMB3S56_MAJOR 45 /* 45 = /dev/eepromb3s56 (cat24c256) */
#define EEPROMB3S57_MAJOR 46 /* 46 = /dev/eepromb3s57 (cat24c256) */
/* Minor device numbers for memory driver. */
# define RAM_DEV_OLD 0 /* minor device for /dev/ram */