imx6 手动进入recovery

写在前面

平板项目，需要音量减+关机键进入recovery模式。中间遇到了一些问题，记录一下。

配置音量键

uboot启动以后会检测音量上下键是否被按，然后进入不同的分支

board/freescale/common/recovery.c

/* export to lib_arm/board.c */
void check_recovery_mode(void)
{
if (check_key_pressing()) {
puts("Fastboot: Recovery key pressing got!\n");
setup_recovery_env();
} else if (check_recovery_cmd_file()) {
puts("Fastboot: Recovery command file found!\n");
setup_recovery_env();
} else {
puts("Fastboot: Normal\n");
}
}

#define GPIO_VOL_DN_KEY IMX_GPIO_NR(2, 1)
iomux_v3_cfg_t const recovery_key_pads[] = {
(MX6_PAD_NANDF_D1__GPIO2_IO01 | MUX_PAD_CTRL(NO_PAD_CTRL)),
};

int check_recovery_cmd_file(void)
{
int button_pressed = 0;
int recovery_mode = 0;

recovery_mode = recovery_check_and_clean_flag();

/* Check Recovery Combo Button press or not. */
imx_iomux_v3_setup_multiple_pads(recovery_key_pads,
ARRAY_SIZE(recovery_key_pads));

gpio_direction_input(GPIO_VOL_DN_KEY);      //由此可见，uboot阶段，会读取一个gpio口，把这个gpio设置为自己主板对应的就能进入recovery了

if (gpio_get_value(GPIO_VOL_DN_KEY) == 0) { /* VOL_DN key is low assert */
button_pressed = 1;
printf("Recovery key pressed\n");
}

return recovery_mode || button_pressed;
}

图形模式和show_text模式

上面已经做好了开机时按住音量减进入recovery模式，但是发现进入recovery后，什么显示都没有。

然后在代码中发现了，由show_text这个变量，如果像要有问题提示，就要把show_text变量设置为1，这个变量的修改是从/cache/recovery/command文件中解析出来的

然后我正常进入系统，执行下面的命令，成功进入带文字提示的recovery

echo "--show_text" > /cache/recovery/command

static const struct option OPTIONS[] = {
{ "send_intent", required_argument, NULL, 's' },
{ "update_package", required_argument, NULL, 'u' },
{ "wipe_data", no_argument, NULL, 'w' },
{ "wipe_cache", no_argument, NULL, 'c' },
{ "show_text", no_argument, NULL, 't' },
{ "just_exit", no_argument, NULL, 'x' },
{ "locale", required_argument, NULL, 'l' },
{ "stages", required_argument, NULL, 'g' },
{ "shutdown_after", no_argument, NULL, 'p' },
{ "reason", required_argument, NULL, 'r' },
{ NULL, 0, NULL, 0 },
};

//bootable/recovery/recovery.cpp
main()
{
......
int wipe_data = 0, wipe_cache = 0, show_text = 0;
......
while ((arg = getopt_long(argc, argv, "", OPTIONS, NULL)) != -1) {
switch (arg) {
case 's': send_intent = optarg; break;
case 'u': update_package = optarg; break;
case 'w': wipe_data = wipe_cache = 1; break;
case 'c': wipe_cache = 1; break;
case 't': show_text = 1; break;
case 'x': just_exit = true; break;
case 'l': locale = optarg; break;
case 'g': {
if (stage == NULL || *stage == '\0') {
char buffer[20] = "1/";
strncat(buffer, optarg, sizeof(buffer)-3);
stage = strdup(buffer);
}
break;
}
case 'p': shutdown_after = true; break;
case 'r': reason = optarg; break;
case '?':
LOGE("Invalid command argument\n");
continue;
}
}
}

根据项目需要，用户从过app升级/恢复出厂，要进入图形模式，手动按键进入recovery，要进入文字模式。

修改代码如下，解决问题

main()
{
......
int wipe_data = 0, wipe_cache = 0, show_text = 1;
......
while ((arg = getopt_long(argc, argv, "", OPTIONS, NULL)) != -1) {
switch (arg) {
case 's': {send_intent = optarg; break;}
case 'u': {show_text = 0; update_package = optarg; break;}
case 'w': {show_text = 0; wipe_data = wipe_cache = 1; break;}
case 'c': {show_text = 0; wipe_cache = 1; break;}
case 't': {show_text = 1; break;}
case 'x': {show_text = 0; just_exit = true; break;}
case 'l': {locale = optarg; break;}
case 'g': {
if (stage == NULL || *stage == '\0') {
char buffer[20] = "1/";
strncat(buffer, optarg, sizeof(buffer)-3);
stage = strdup(buffer);
}
break;
}
case 'p': shutdown_after = true; break;
case 'r': reason = optarg; break;
case '?':
LOGE("Invalid command argument\n");
continue;
}
}
}

也就是，默认是显示文字，不显示图形的。 如果用户通过app进行恢复出厂/升级系统，那么设置show_text=0，进入图形模式。