1*0d6140beSAndroid Build Coastguard Worker /*
2*0d6140beSAndroid Build Coastguard Worker * This file is part of the flashrom project.
3*0d6140beSAndroid Build Coastguard Worker *
4*0d6140beSAndroid Build Coastguard Worker * Copyright (C) 2020 The Chromium OS Authors
5*0d6140beSAndroid Build Coastguard Worker *
6*0d6140beSAndroid Build Coastguard Worker * This program is free software; you can redistribute it and/or modify
7*0d6140beSAndroid Build Coastguard Worker * it under the terms of the GNU General Public License as published by
8*0d6140beSAndroid Build Coastguard Worker * the Free Software Foundation; either version 2 of the License, or
9*0d6140beSAndroid Build Coastguard Worker * (at your option) any later version.
10*0d6140beSAndroid Build Coastguard Worker *
11*0d6140beSAndroid Build Coastguard Worker * This program is distributed in the hope that it will be useful,
12*0d6140beSAndroid Build Coastguard Worker * but WITHOUT ANY WARRANTY; without even the implied warranty of
13*0d6140beSAndroid Build Coastguard Worker * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14*0d6140beSAndroid Build Coastguard Worker * GNU General Public License for more details.
15*0d6140beSAndroid Build Coastguard Worker */
16*0d6140beSAndroid Build Coastguard Worker
17*0d6140beSAndroid Build Coastguard Worker #include <errno.h>
18*0d6140beSAndroid Build Coastguard Worker #include <stdio.h>
19*0d6140beSAndroid Build Coastguard Worker #include <string.h>
20*0d6140beSAndroid Build Coastguard Worker #include <fcntl.h>
21*0d6140beSAndroid Build Coastguard Worker #include <sys/ioctl.h>
22*0d6140beSAndroid Build Coastguard Worker #include <unistd.h>
23*0d6140beSAndroid Build Coastguard Worker
24*0d6140beSAndroid Build Coastguard Worker #include <stdlib.h>
25*0d6140beSAndroid Build Coastguard Worker #include <linux/i2c.h>
26*0d6140beSAndroid Build Coastguard Worker #include <linux/i2c-dev.h>
27*0d6140beSAndroid Build Coastguard Worker
28*0d6140beSAndroid Build Coastguard Worker #include "flash.h"
29*0d6140beSAndroid Build Coastguard Worker #include "i2c_helper.h"
30*0d6140beSAndroid Build Coastguard Worker #include "programmer.h"
31*0d6140beSAndroid Build Coastguard Worker
32*0d6140beSAndroid Build Coastguard Worker /* Null characters are placeholders for bus number digits */
33*0d6140beSAndroid Build Coastguard Worker #define I2C_DEV_PREFIX "/dev/i2c-\0\0\0"
34*0d6140beSAndroid Build Coastguard Worker #define I2C_MAX_BUS 255
35*0d6140beSAndroid Build Coastguard Worker
i2c_close(int fd)36*0d6140beSAndroid Build Coastguard Worker int i2c_close(int fd)
37*0d6140beSAndroid Build Coastguard Worker {
38*0d6140beSAndroid Build Coastguard Worker return fd == -1 ? 0 : close(fd);
39*0d6140beSAndroid Build Coastguard Worker }
40*0d6140beSAndroid Build Coastguard Worker
i2c_open_path(const char * path,uint16_t addr,int force)41*0d6140beSAndroid Build Coastguard Worker int i2c_open_path(const char *path, uint16_t addr, int force)
42*0d6140beSAndroid Build Coastguard Worker {
43*0d6140beSAndroid Build Coastguard Worker int fd = open(path, O_RDWR);
44*0d6140beSAndroid Build Coastguard Worker if (fd < 0) {
45*0d6140beSAndroid Build Coastguard Worker msg_perr("Unable to open I2C device %s: %s.\n", path, strerror(errno));
46*0d6140beSAndroid Build Coastguard Worker return fd;
47*0d6140beSAndroid Build Coastguard Worker }
48*0d6140beSAndroid Build Coastguard Worker
49*0d6140beSAndroid Build Coastguard Worker int request = force ? I2C_SLAVE_FORCE : I2C_SLAVE;
50*0d6140beSAndroid Build Coastguard Worker int ret = ioctl(fd, request, addr);
51*0d6140beSAndroid Build Coastguard Worker if (ret < 0) {
52*0d6140beSAndroid Build Coastguard Worker msg_perr("Unable to set I2C slave address to 0x%02x: %s.\n", addr, strerror(errno));
53*0d6140beSAndroid Build Coastguard Worker i2c_close(fd);
54*0d6140beSAndroid Build Coastguard Worker return ret;
55*0d6140beSAndroid Build Coastguard Worker }
56*0d6140beSAndroid Build Coastguard Worker
57*0d6140beSAndroid Build Coastguard Worker return fd;
58*0d6140beSAndroid Build Coastguard Worker }
59*0d6140beSAndroid Build Coastguard Worker
i2c_open(int bus,uint16_t addr,int force)60*0d6140beSAndroid Build Coastguard Worker int i2c_open(int bus, uint16_t addr, int force)
61*0d6140beSAndroid Build Coastguard Worker {
62*0d6140beSAndroid Build Coastguard Worker char dev[sizeof(I2C_DEV_PREFIX)] = {0};
63*0d6140beSAndroid Build Coastguard Worker
64*0d6140beSAndroid Build Coastguard Worker int ret = -1;
65*0d6140beSAndroid Build Coastguard Worker
66*0d6140beSAndroid Build Coastguard Worker if (bus < 0 || bus > I2C_MAX_BUS) {
67*0d6140beSAndroid Build Coastguard Worker msg_perr("Invalid I2C bus %d.\n", bus);
68*0d6140beSAndroid Build Coastguard Worker return ret;
69*0d6140beSAndroid Build Coastguard Worker }
70*0d6140beSAndroid Build Coastguard Worker
71*0d6140beSAndroid Build Coastguard Worker ret = snprintf(dev, sizeof(dev), "%s%d", I2C_DEV_PREFIX, bus);
72*0d6140beSAndroid Build Coastguard Worker if (ret < 0) {
73*0d6140beSAndroid Build Coastguard Worker msg_perr("Unable to join bus number to device name: %s.\n", strerror(errno));
74*0d6140beSAndroid Build Coastguard Worker return ret;
75*0d6140beSAndroid Build Coastguard Worker }
76*0d6140beSAndroid Build Coastguard Worker
77*0d6140beSAndroid Build Coastguard Worker return i2c_open_path(dev, addr, force);
78*0d6140beSAndroid Build Coastguard Worker }
79*0d6140beSAndroid Build Coastguard Worker
get_bus_number(char * bus_str)80*0d6140beSAndroid Build Coastguard Worker static int get_bus_number(char *bus_str)
81*0d6140beSAndroid Build Coastguard Worker {
82*0d6140beSAndroid Build Coastguard Worker char *bus_suffix;
83*0d6140beSAndroid Build Coastguard Worker errno = 0;
84*0d6140beSAndroid Build Coastguard Worker int bus = (int)strtol(bus_str, &bus_suffix, 10);
85*0d6140beSAndroid Build Coastguard Worker if (errno != 0 || bus_str == bus_suffix) {
86*0d6140beSAndroid Build Coastguard Worker msg_perr("%s: Could not convert 'bus'.\n", __func__);
87*0d6140beSAndroid Build Coastguard Worker return -1;
88*0d6140beSAndroid Build Coastguard Worker }
89*0d6140beSAndroid Build Coastguard Worker
90*0d6140beSAndroid Build Coastguard Worker if (strlen(bus_suffix) > 0) {
91*0d6140beSAndroid Build Coastguard Worker msg_perr("%s: Garbage following 'bus' value.\n", __func__);
92*0d6140beSAndroid Build Coastguard Worker return -1;
93*0d6140beSAndroid Build Coastguard Worker }
94*0d6140beSAndroid Build Coastguard Worker
95*0d6140beSAndroid Build Coastguard Worker msg_pinfo("Using I2C bus %d.\n", bus);
96*0d6140beSAndroid Build Coastguard Worker return bus;
97*0d6140beSAndroid Build Coastguard Worker }
98*0d6140beSAndroid Build Coastguard Worker
i2c_open_from_programmer_params(const struct programmer_cfg * cfg,uint16_t addr,int force)99*0d6140beSAndroid Build Coastguard Worker int i2c_open_from_programmer_params(const struct programmer_cfg *cfg, uint16_t addr, int force)
100*0d6140beSAndroid Build Coastguard Worker {
101*0d6140beSAndroid Build Coastguard Worker int fd = -1;
102*0d6140beSAndroid Build Coastguard Worker
103*0d6140beSAndroid Build Coastguard Worker char *bus_str = extract_programmer_param_str(cfg, "bus");
104*0d6140beSAndroid Build Coastguard Worker char *device_path = extract_programmer_param_str(cfg, "devpath");
105*0d6140beSAndroid Build Coastguard Worker
106*0d6140beSAndroid Build Coastguard Worker if (device_path != NULL && bus_str != NULL) {
107*0d6140beSAndroid Build Coastguard Worker msg_perr("%s: only one of bus and devpath may be specified\n", __func__);
108*0d6140beSAndroid Build Coastguard Worker goto out;
109*0d6140beSAndroid Build Coastguard Worker }
110*0d6140beSAndroid Build Coastguard Worker if (device_path == NULL && bus_str == NULL) {
111*0d6140beSAndroid Build Coastguard Worker msg_perr("%s: one of bus and devpath must be specified\n", __func__);
112*0d6140beSAndroid Build Coastguard Worker goto out;
113*0d6140beSAndroid Build Coastguard Worker }
114*0d6140beSAndroid Build Coastguard Worker
115*0d6140beSAndroid Build Coastguard Worker if (device_path != NULL)
116*0d6140beSAndroid Build Coastguard Worker fd = i2c_open_path(device_path, addr, force);
117*0d6140beSAndroid Build Coastguard Worker else
118*0d6140beSAndroid Build Coastguard Worker fd = i2c_open(get_bus_number(bus_str), addr, force);
119*0d6140beSAndroid Build Coastguard Worker
120*0d6140beSAndroid Build Coastguard Worker out:
121*0d6140beSAndroid Build Coastguard Worker free(bus_str);
122*0d6140beSAndroid Build Coastguard Worker free(device_path);
123*0d6140beSAndroid Build Coastguard Worker return fd;
124*0d6140beSAndroid Build Coastguard Worker }
125*0d6140beSAndroid Build Coastguard Worker
i2c_read(int fd,uint16_t addr,i2c_buffer_t * buf)126*0d6140beSAndroid Build Coastguard Worker int i2c_read(int fd, uint16_t addr, i2c_buffer_t *buf)
127*0d6140beSAndroid Build Coastguard Worker {
128*0d6140beSAndroid Build Coastguard Worker if (buf->len == 0)
129*0d6140beSAndroid Build Coastguard Worker return 0;
130*0d6140beSAndroid Build Coastguard Worker
131*0d6140beSAndroid Build Coastguard Worker int ret = ioctl(fd, I2C_SLAVE, addr);
132*0d6140beSAndroid Build Coastguard Worker if (ret < 0) {
133*0d6140beSAndroid Build Coastguard Worker msg_perr("Unable to set I2C slave address to 0x%02x: %s.\n", addr, strerror(errno));
134*0d6140beSAndroid Build Coastguard Worker return ret;
135*0d6140beSAndroid Build Coastguard Worker }
136*0d6140beSAndroid Build Coastguard Worker
137*0d6140beSAndroid Build Coastguard Worker return read(fd, buf->buf, buf->len);
138*0d6140beSAndroid Build Coastguard Worker }
139*0d6140beSAndroid Build Coastguard Worker
i2c_write(int fd,uint16_t addr,const i2c_buffer_t * buf)140*0d6140beSAndroid Build Coastguard Worker int i2c_write(int fd, uint16_t addr, const i2c_buffer_t *buf)
141*0d6140beSAndroid Build Coastguard Worker {
142*0d6140beSAndroid Build Coastguard Worker if (buf->len == 0)
143*0d6140beSAndroid Build Coastguard Worker return 0;
144*0d6140beSAndroid Build Coastguard Worker
145*0d6140beSAndroid Build Coastguard Worker int ret = ioctl(fd, I2C_SLAVE, addr);
146*0d6140beSAndroid Build Coastguard Worker if (ret < 0) {
147*0d6140beSAndroid Build Coastguard Worker msg_perr("Unable to set I2C slave address to 0x%02x: %s.\n", addr, strerror(errno));
148*0d6140beSAndroid Build Coastguard Worker return ret;
149*0d6140beSAndroid Build Coastguard Worker }
150*0d6140beSAndroid Build Coastguard Worker
151*0d6140beSAndroid Build Coastguard Worker return write(fd, buf->buf, buf->len);
152*0d6140beSAndroid Build Coastguard Worker }
153