Files
cdba/cdb_assist.c
Bjorn Andersson 4efcfb4456 bad: Add initial cdba backend implementation
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
2018-03-12 17:43:55 -07:00

514 lines
9.5 KiB
C

#include <sys/types.h>
#include <ctype.h>
#include <dirent.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <termios.h>
#include <unistd.h>
#include "bad.h"
struct cdb_assist {
char serial[9];
char control_uart[20];
char target_uart[20];
int control_tty;
int target_tty;
struct termios control_tios;
struct termios target_tios;
struct cdb_assist *next;
/* parser */
unsigned state;
unsigned num[2];
char key[32];
unsigned key_idx;
bool voltage;
/* state */
unsigned current_actual;
unsigned current_set;
unsigned voltage_actual;
unsigned voltage_set;
bool vbat;
bool btn[3];
bool vbus;
unsigned vref;
};
static int readat(int dir, const char *name, char *buf, size_t len)
{
ssize_t n;
int fd;
int ret = 0;
fd = openat(dir, name, O_RDONLY);
if (fd < 0)
return fd;
n = read(fd, buf, len - 1);
if (n < 0) {
warn("failed to read %s", name);
ret = -EINVAL;
goto close_fd;
}
buf[n] = '\0';
buf[strcspn(buf, "\n")] = '\0';
close_fd:
close(fd);
return ret;
}
static struct cdb_assist *enumerate_cdb_assists()
{
struct cdb_assist *cdb;
struct cdb_assist *all = NULL;
struct cdb_assist *last = NULL;
struct dirent *de;
char interface[30];
char serial[9];
DIR *dir;
int tty;
int fd;
int ret;
tty = open("/sys/class/tty", O_DIRECTORY);
if (tty < 0)
err(1, "failed to open /sys/class/tty");
dir = fdopendir(tty);
if (!dir)
err(1, "failed to opendir /sys/class/tty");
while ((de = readdir(dir)) != NULL) {
if (strncmp(de->d_name, "ttyACM", 6) != 0)
continue;
fd = openat(tty, de->d_name, O_DIRECTORY);
if (fd < 0)
continue;
ret = readat(fd, "../../interface", interface, sizeof(interface));
if (ret < 0)
goto close_fd;
ret = readat(fd, "../../../serial", serial, sizeof(serial));
if (ret < 0)
goto close_fd;
for (cdb = all; cdb; cdb = cdb->next) {
if (strcmp(cdb->serial, serial) == 0)
break;
}
if (!cdb) {
cdb = calloc(1, sizeof(*cdb));
strcpy(cdb->serial, serial);
if (last) {
last->next = cdb;
last = cdb;
} else {
last = cdb;
all = cdb;
}
}
if (strcmp(interface, "Control UART") == 0)
strcpy(cdb->control_uart, de->d_name);
else if (strcmp(interface, "Target UART") == 0)
strcpy(cdb->target_uart, de->d_name);
else
errx(1, "tty is neither control nor target\n");
close_fd:
close(fd);
}
closedir(dir);
close(tty);
return all;
}
static struct cdb_assist *cdb_assist_find(const char *serial)
{
struct cdb_assist *cdb;
struct cdb_assist *all;
all = enumerate_cdb_assists();
for (cdb = all; cdb; cdb = cdb->next) {
if (strcmp(cdb->serial, serial) == 0)
return cdb;
}
return NULL;
}
static int tty_open(const char *tty, struct termios *old)
{
struct termios tios;
char buf[80] = "/dev/";
int ret;
int fd;
strcat(buf, tty);
fd = open(buf, O_RDWR | O_NOCTTY | O_EXCL);
if (fd < 0)
err(1, "unable to open \"%s\"", tty);
ret = tcgetattr(fd, old);
if (ret < 0)
err(1, "unable to retrieve \"%s\" tios", tty);
memset(&tios, 0, sizeof(tios));
tios.c_cflag = B115200 | CRTSCTS | CS8 | CLOCAL | CREAD;
tios.c_iflag = IGNPAR;
tios.c_oflag = 0;
tcflush(fd, TCIFLUSH);
ret = tcsetattr(fd, TCSANOW, &tios);
if (ret < 0)
err(1, "unable to update \"%s\" tios", tty);
return fd;
}
enum {
STATE_,
STATE_key,
STATE_key_bool,
STATE_key_value,
STATE_key_o,
STATE_key_of,
STATE_key_num,
STATE_key_num_m,
STATE_num,
STATE_num_m,
STATE_num_mX,
STATE_num_mX_,
STATE_num_num_m,
};
static void cdb_parser_bool(struct cdb_assist *cdb, const char *key, bool set)
{
static const char *sz_keys[] = { "vbat", "btn1", "btn2", "btn3", "vbus" };
int i;
for (i = 0; i < 5; i++)
if (strcmp(key, sz_keys[i]) == 0)
break;
switch (i) {
case 0:
cdb->vbat = set;
break;
case 1:
case 2:
case 3:
cdb->btn[i-1] = set;
break;
case 4:
cdb->vbus = set;
break;
}
}
static void cdb_parser_current(struct cdb_assist *cdb, unsigned set, unsigned actual)
{
cdb->current_actual = actual;
cdb->current_set = set;
}
static void cdb_parser_voltage(struct cdb_assist *cdb, unsigned set, unsigned actual)
{
cdb->voltage_actual = actual;
cdb->voltage_set = set;
}
static void cdb_parser_vref(struct cdb_assist *cdb, unsigned vref)
{
cdb->vref = vref;
}
static void cdb_parser_push(struct cdb_assist *cdb, char ch)
{
switch (cdb->state) {
case STATE_:
if (isdigit(ch)) {
cdb->num[0] = ch - '0';
cdb->state = STATE_num;
} else if (isalpha(ch)) {
cdb->key[0] = ch;
cdb->key_idx = 1;
cdb->state = STATE_key;
}
break;
case STATE_num:
if (isdigit(ch)) {
cdb->num[0] *= 10;
cdb->num[0] += ch - '0';
} else if (ch == 'm') {
cdb->state = STATE_num_m;
} else {
cdb->state = STATE_;
}
break;
case STATE_num_m:
if (ch == 'v') {
cdb->voltage = true;
cdb->state = STATE_num_mX;
} else if (ch == 'a') {
cdb->voltage = false;
cdb->state = STATE_num_mX;
} else {
cdb->state = STATE_;
}
break;
case STATE_num_mX:
if (ch == '/') {
cdb->num[1] = 0;
cdb->state = STATE_num_mX_;
} else {
cdb->state = STATE_;
}
break;
case STATE_num_mX_:
if (isdigit(ch)) {
cdb->num[1] *= 10;
cdb->num[1] += ch - '0';
} else if (ch == 'm') {
cdb->state = STATE_num_num_m;
} else {
cdb->state = STATE_;
}
break;
case STATE_num_num_m:
if (ch == 'v' && cdb->voltage)
cdb_parser_voltage(cdb, cdb->num[0], cdb->num[1]);
else if (ch == 'a' && !cdb->voltage)
cdb_parser_current(cdb, cdb->num[0], cdb->num[1]);
cdb->state = STATE_;
break;
case STATE_key:
if (isalnum(ch)) {
cdb->key[cdb->key_idx++] = ch;
} else if (ch == ':') {
cdb->key[cdb->key_idx] = '\0';
cdb->state = STATE_key_bool;
} else if (ch == '=') {
cdb->key[cdb->key_idx] = '\0';
cdb->state = STATE_key_value;
} else {
cdb->state = STATE_;
}
break;
case STATE_key_bool:
if (ch == 'o')
cdb->state = STATE_key_o;
else
cdb->state = STATE_;
break;
case STATE_key_o:
if (ch == 'f') {
cdb->state = STATE_key_of;
} else if (ch == 'n') {
cdb_parser_bool(cdb, cdb->key, true);
cdb->state = STATE_;
} else {
cdb->state = STATE_;
}
break;
case STATE_key_of:
if (ch == 'f')
cdb_parser_bool(cdb, cdb->key, false);
cdb->state = STATE_;
break;
case STATE_key_value:
if (isdigit(ch)) {
cdb->num[0] = ch - '0';
cdb->state = STATE_key_num;
} else {
cdb->state = STATE_;
}
break;
case STATE_key_num:
if (isdigit(ch)) {
cdb->num[0] *= 10;
cdb->num[0] += ch - '0';
} else if (ch == 'm') {
cdb->state = STATE_key_num_m;
} else {
cdb->state = STATE_;
}
break;
case STATE_key_num_m:
if (ch == 'v')
cdb_parser_vref(cdb, cdb->num[0]);
cdb->state = STATE_;
break;
}
}
static int cdb_assist_ctrl_data(int fd, void *data)
{
struct cdb_assist *cdb = data;
char buf[10];
ssize_t n;
ssize_t k;
n = read(fd, buf, sizeof(buf) - 1);
if (n < 0)
return n;
for (k = 0; k < n; k++)
cdb_parser_push(cdb, tolower(buf[k]));
return 0;
}
static int cdb_assist_target_data(int fd, void *data)
{
struct msg hdr;
char buf[128];
ssize_t n;
n = read(fd, buf, sizeof(buf));
if (n < 0)
return n;
hdr.type = MSG_CONSOLE;
hdr.len = n;
write(STDOUT_FILENO, &hdr, sizeof(hdr));
write(STDOUT_FILENO, buf, n);
return 0;
}
static int cdb_ctrl_write(struct cdb_assist *cdb, const char *buf, size_t len)
{
return write(cdb->control_tty, buf, len);
}
struct cdb_assist *cdb_assist_open(const char *serial)
{
struct cdb_assist *cdb;
int ret;
cdb = cdb_assist_find(serial);
if (!cdb) {
fprintf(stderr, "unable to find cdb assist with serial %s\n", serial);
return NULL;
}
cdb->control_tty = tty_open(cdb->control_uart, &cdb->control_tios);
if (cdb->control_tty < 0)
return NULL;
cdb->target_tty = tty_open(cdb->target_uart, &cdb->target_tios);
if (cdb->target_tty < 0)
return NULL;
watch_add_readfd(cdb->control_tty, cdb_assist_ctrl_data, cdb);
watch_add_readfd(cdb->target_tty, cdb_assist_target_data, cdb);
ret = cdb_ctrl_write(cdb, "vpabc", 5);
if (ret < 0)
return NULL;
return cdb;
}
void cdb_assist_close(struct cdb_assist *cdb)
{
int ret;
tcflush(cdb->control_tty, TCIFLUSH);
ret = tcsetattr(cdb->target_tty, TCSAFLUSH, &cdb->target_tios);
if (ret < 0)
warn("unable to restore tios of \"%s\"", cdb->target_uart);
close(cdb->control_tty);
close(cdb->target_tty);
}
void cdb_power(struct cdb_assist *cdb, bool on)
{
const char cmd[] = "pP";
cdb_ctrl_write(cdb, &cmd[on], 1);
}
void cdb_vbus(struct cdb_assist *cdb, bool on)
{
const char cmd[] = "vV";
cdb_ctrl_write(cdb, &cmd[on], 1);
}
void cdb_gpio(struct cdb_assist *cdb, int gpio, bool on)
{
const char *cmd[] = { "aA", "bB", "cC" };
cdb_ctrl_write(cdb, &cmd[gpio][on], 1);
}
int cdb_target_write(struct cdb_assist *cdb, const void *buf, size_t len)
{
return write(cdb->target_tty, buf, len);
}
void cdb_target_break(struct cdb_assist *cdb)
{
tcsendbreak(cdb->target_tty, 0);
}
int cdb_vref(struct cdb_assist *cdb)
{
return cdb->vref;
}
void cdb_assist_print_status(struct cdb_assist *cdb)
{
struct msg hdr;
char buf[128];
int n;
n = sprintf(buf, "%dmV %dmA%s%s%s%s%s ref: %dmV",
cdb->voltage_set,
cdb->current_actual,
cdb->vbat ? " vbat" : "",
cdb->vbus ? " vbus" : "",
cdb->btn[0] ? " btn1" : "",
cdb->btn[1] ? " btn2" : "",
cdb->btn[2] ? " btn3" : "",
cdb->vref);
hdr.type = MSG_STATUS_UPDATE;
hdr.len = n;
write(STDOUT_FILENO, &hdr, sizeof(hdr));
write(STDOUT_FILENO, buf, n);
}
void cdb_set_voltage(struct cdb_assist *cdb, unsigned mV)
{
char buf[20];
int n;
n = sprintf(buf, "u%d\r\n", mV);
cdb_ctrl_write(cdb, buf, n);
}