core: Add a standalone charger UI binary
This can be launched from an 'on charger' section in init, which
is processed if androidboot.mode=charger is supplied on kernel
command line.
This is a standalone binary that has a simple "user interface"
and allows the standard production kernel to run while charging.
This removes the burden from the bootloader to get low-power mode
working.
Currently, the device will "power-on" (i.e. reboot) into normal
mode if the power key is pressed for X seconds, and will also
power down the device if the usb/ac cable is removed for Y seconds.
Change-Id: I780594b99211cb09de7f8519a69c5962eb91348a
Signed-off-by: Dima Zavin <dima@android.com>
diff --git a/charger/charger.c b/charger/charger.c
new file mode 100644
index 0000000..5397487
--- /dev/null
+++ b/charger/charger.c
@@ -0,0 +1,726 @@
+/*
+ * Copyright (C) 2011 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+//#define DEBUG_UEVENTS
+#define CHARGER_KLOG_LEVEL 6
+
+#include <dirent.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <linux/input.h>
+#include <linux/netlink.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/poll.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/un.h>
+#include <time.h>
+#include <unistd.h>
+
+#include <cutils/android_reboot.h>
+#include <cutils/klog.h>
+#include <cutils/list.h>
+#include <cutils/uevent.h>
+
+#include "minui/minui.h"
+
+#ifndef max
+#define max(a,b) ((a) > (b) ? (a) : (b))
+#endif
+
+#ifndef min
+#define min(a,b) ((a) < (b) ? (a) : (b))
+#endif
+
+#define MSEC_PER_SEC (1000LL)
+#define NSEC_PER_MSEC (1000000LL)
+
+#define SCREEN_ON_TIME (5 * MSEC_PER_SEC)
+#define POWER_ON_KEY_TIME (5 * MSEC_PER_SEC)
+#define UNPLUGGED_SHUTDOWN_TIME (10 * MSEC_PER_SEC)
+
+#define LOGE(x...) do { KLOG_ERROR("charger", x); } while (0)
+#define LOGI(x...) do { KLOG_INFO("charger", x); } while (0)
+#define LOGV(x...) do { KLOG_DEBUG("charger", x); } while (0)
+
+struct key_state {
+ bool pending;
+ bool down;
+ int64_t timestamp;
+};
+
+struct power_supply {
+ struct listnode list;
+ char name[256];
+ char type[32];
+ bool online;
+ bool valid;
+};
+
+struct charger {
+ int64_t next_screen_transition;
+ int64_t next_key_check;
+ int64_t next_pwr_check;
+ bool screen_on;
+
+ struct key_state keys[KEY_MAX + 1];
+ gr_surface surf_charging;
+ int uevent_fd;
+
+ struct listnode supplies;
+ int num_supplies;
+ int num_supplies_online;
+
+ struct power_supply *battery;
+};
+
+struct uevent {
+ const char *action;
+ const char *path;
+ const char *subsystem;
+ const char *ps_name;
+ const char *ps_type;
+ const char *ps_online;
+};
+
+static int char_width;
+static int char_height;
+
+struct charger charger_state;
+
+/* current time in milliseconds */
+static int64_t curr_time_ms(void)
+{
+ struct timespec tm;
+ clock_gettime(CLOCK_MONOTONIC, &tm);
+ return tm.tv_sec * MSEC_PER_SEC + (tm.tv_nsec / NSEC_PER_MSEC);
+}
+
+static void clear_screen(void)
+{
+ gr_color(0, 0, 0, 255);
+ gr_fill(0, 0, gr_fb_width(), gr_fb_height());
+};
+
+static int read_file(const char *path, char *buf, size_t sz)
+{
+ int fd;
+ size_t cnt;
+
+ fd = open(path, O_RDONLY, 0);
+ if (fd < 0)
+ goto err;
+
+ cnt = read(fd, buf, sz - 1);
+ if (cnt <= 0)
+ goto err;
+ buf[cnt] = '\0';
+ if (buf[cnt - 1] == '\n') {
+ cnt--;
+ buf[cnt] = '\0';
+ }
+
+ close(fd);
+ return cnt;
+
+err:
+ if (fd >= 0)
+ close(fd);
+ return -1;
+}
+
+static int read_file_int(const char *path, int *val)
+{
+ char buf[32];
+ int ret;
+ int tmp;
+ char *end;
+
+ ret = read_file(path, buf, sizeof(buf));
+ if (ret < 0)
+ return -1;
+
+ tmp = strtol(buf, &end, 0);
+ if (end == buf ||
+ ((end < buf+sizeof(buf)) && (*end != '\n' && *end != '\0')))
+ goto err;
+
+ *val = tmp;
+ return 0;
+
+err:
+ return -1;
+}
+
+static struct power_supply *find_supply(struct charger *charger,
+ const char *name)
+{
+ struct listnode *node;
+ struct power_supply *supply;
+
+ list_for_each(node, &charger->supplies) {
+ supply = node_to_item(node, struct power_supply, list);
+ if (!strncmp(name, supply->name, sizeof(supply->name)))
+ return supply;
+ }
+ return NULL;
+}
+
+static struct power_supply *add_supply(struct charger *charger,
+ const char *name, const char *type,
+ bool online)
+{
+ struct power_supply *supply;
+
+ supply = calloc(1, sizeof(struct power_supply));
+ if (!supply)
+ return NULL;
+
+ strlcpy(supply->name, name, sizeof(supply->name));
+ strlcpy(supply->type, type, sizeof(supply->type));
+ supply->online = online;
+ list_add_tail(&charger->supplies, &supply->list);
+ charger->num_supplies++;
+ LOGV("... added %s %s %d\n", supply->name, supply->type, online);
+ return supply;
+}
+
+static void remove_supply(struct charger *charger, struct power_supply *supply)
+{
+ if (!supply)
+ return;
+ list_remove(&supply->list);
+ charger->num_supplies--;
+ free(supply);
+}
+
+static void parse_uevent(const char *msg, struct uevent *uevent)
+{
+ uevent->action = "";
+ uevent->path = "";
+ uevent->subsystem = "";
+ uevent->ps_name = "";
+ uevent->ps_online = "";
+ uevent->ps_type = "";
+
+ /* currently ignoring SEQNUM */
+ while (*msg) {
+#ifdef DEBUG_UEVENTS
+ LOGV("uevent str: %s\n", msg);
+#endif
+ if (!strncmp(msg, "ACTION=", 7)) {
+ msg += 7;
+ uevent->action = msg;
+ } else if (!strncmp(msg, "DEVPATH=", 8)) {
+ msg += 8;
+ uevent->path = msg;
+ } else if (!strncmp(msg, "SUBSYSTEM=", 10)) {
+ msg += 10;
+ uevent->subsystem = msg;
+ } else if (!strncmp(msg, "POWER_SUPPLY_NAME=", 18)) {
+ msg += 18;
+ uevent->ps_name = msg;
+ } else if (!strncmp(msg, "POWER_SUPPLY_ONLINE=", 20)) {
+ msg += 20;
+ uevent->ps_online = msg;
+ } else if (!strncmp(msg, "POWER_SUPPLY_TYPE=", 18)) {
+ msg += 18;
+ uevent->ps_type = msg;
+ }
+
+ /* advance to after the next \0 */
+ while (*msg++)
+ ;
+ }
+
+ LOGV("event { '%s', '%s', '%s', '%s', '%s', '%s' }\n",
+ uevent->action, uevent->path, uevent->subsystem,
+ uevent->ps_name, uevent->ps_type, uevent->ps_online);
+}
+
+static void process_ps_uevent(struct charger *charger, struct uevent *uevent)
+{
+ int online;
+ char ps_type[32];
+ struct power_supply *supply = NULL;
+ int i;
+ bool was_online = false;
+ bool battery = false;
+
+ if (uevent->ps_type[0] == '\0') {
+ char *path;
+ int ret;
+
+ if (uevent->path[0] == '\0')
+ return;
+ ret = asprintf(&path, "/sys/%s/type", uevent->path);
+ if (ret <= 0)
+ return;
+ ret = read_file(path, ps_type, sizeof(ps_type));
+ free(path);
+ if (ret < 0)
+ return;
+ } else {
+ strlcpy(ps_type, uevent->ps_type, sizeof(ps_type));
+ }
+
+ if (!strncmp(ps_type, "Battery", 7))
+ battery = true;
+
+ online = atoi(uevent->ps_online);
+ supply = find_supply(charger, uevent->ps_name);
+ if (supply) {
+ was_online = supply->online;
+ supply->online = online;
+ }
+
+ if (!strcmp(uevent->action, "add")) {
+ if (!supply) {
+ supply = add_supply(charger, uevent->ps_name, ps_type, online);
+ if (!supply) {
+ LOGE("cannot add supply '%s' (%s %d)\n", uevent->ps_name,
+ uevent->ps_type, online);
+ return;
+ }
+ /* only pick up the first battery for now */
+ if (battery && !charger->battery)
+ charger->battery = supply;
+ } else {
+ LOGE("supply '%s' already exists..\n", uevent->ps_name);
+ }
+ } else if (!strcmp(uevent->action, "remove")) {
+ if (supply) {
+ if (charger->battery == supply)
+ charger->battery = NULL;
+ remove_supply(charger, supply);
+ supply = NULL;
+ }
+ } else if (!strcmp(uevent->action, "change")) {
+ if (!supply) {
+ LOGE("power supply '%s' not found ('%s' %d)\n",
+ uevent->ps_name, ps_type, online);
+ return;
+ }
+ } else {
+ return;
+ }
+
+ /* allow battery to be managed in the supply list but make it not
+ * contribute to online power supplies. */
+ if (!battery) {
+ if (was_online && !online)
+ charger->num_supplies_online--;
+ else if (supply && !was_online && online)
+ charger->num_supplies_online++;
+ }
+
+ LOGI("power supply %s (%s) %s (action=%s num_online=%d num_supplies=%d)\n",
+ uevent->ps_name, ps_type, battery ? "" : online ? "online" : "offline",
+ uevent->action, charger->num_supplies_online, charger->num_supplies);
+}
+
+static void process_uevent(struct charger *charger, struct uevent *uevent)
+{
+ if (!strcmp(uevent->subsystem, "power_supply"))
+ process_ps_uevent(charger, uevent);
+}
+
+#define UEVENT_MSG_LEN 1024
+static int handle_uevent_fd(struct charger *charger, int fd)
+{
+ char msg[UEVENT_MSG_LEN+2];
+ int n;
+
+ if (fd < 0)
+ return -1;
+
+ while (true) {
+ struct uevent uevent;
+
+ n = uevent_kernel_multicast_recv(fd, msg, UEVENT_MSG_LEN);
+ if (n <= 0)
+ break;
+ if (n >= UEVENT_MSG_LEN) /* overflow -- discard */
+ continue;
+
+ msg[n] = '\0';
+ msg[n+1] = '\0';
+
+ parse_uevent(msg, &uevent);
+ process_uevent(charger, &uevent);
+ }
+
+ return 0;
+}
+
+static int uevent_callback(int fd, short revents, void *data)
+{
+ struct charger *charger = data;
+
+ if (!(revents & POLLIN))
+ return -1;
+ return handle_uevent_fd(charger, fd);
+}
+
+/* force the kernel to regenerate the change events for the existing
+ * devices, if valid */
+static void do_coldboot(struct charger *charger, DIR *d, const char *event,
+ bool follow_links, int max_depth)
+{
+ struct dirent *de;
+ int dfd, fd;
+
+ dfd = dirfd(d);
+
+ fd = openat(dfd, "uevent", O_WRONLY);
+ if (fd >= 0) {
+ write(fd, event, strlen(event));
+ close(fd);
+ handle_uevent_fd(charger, charger->uevent_fd);
+ }
+
+ while ((de = readdir(d)) && max_depth > 0) {
+ DIR *d2;
+
+ LOGV("looking at '%s'\n", de->d_name);
+
+ if ((de->d_type != DT_DIR && !(de->d_type == DT_LNK && follow_links)) ||
+ de->d_name[0] == '.') {
+ LOGV("skipping '%s' type %d (depth=%d follow=%d)\n",
+ de->d_name, de->d_type, max_depth, follow_links);
+ continue;
+ }
+ LOGV("can descend into '%s'\n", de->d_name);
+
+ fd = openat(dfd, de->d_name, O_RDONLY | O_DIRECTORY);
+ if (fd < 0) {
+ LOGE("cannot openat %d '%s' (%d: %s)\n", dfd, de->d_name,
+ errno, strerror(errno));
+ continue;
+ }
+
+ d2 = fdopendir(fd);
+ if (d2 == 0)
+ close(fd);
+ else {
+ LOGV("opened '%s'\n", de->d_name);
+ do_coldboot(charger, d2, event, follow_links, max_depth - 1);
+ closedir(d2);
+ }
+ }
+}
+
+static void coldboot(struct charger *charger, const char *path,
+ const char *event)
+{
+ char str[256];
+
+ LOGV("doing coldboot '%s' in '%s'\n", event, path);
+ DIR *d = opendir(path);
+ if (d) {
+ snprintf(str, sizeof(str), "%s\n", event);
+ do_coldboot(charger, d, str, true, 1);
+ closedir(d);
+ }
+}
+
+static int draw_text(const char *str, int x, int y)
+{
+ int str_len_px = gr_measure(str);
+
+ if (x < 0)
+ x = (gr_fb_width() - str_len_px) / 2;
+ if (y < 0)
+ y = (gr_fb_height() - char_height) / 2;
+ gr_text(x, y, str);
+
+ return y + char_height;
+}
+
+static void android_green(void)
+{
+ gr_color(0xa4, 0xc6, 0x39, 255);
+}
+
+static void redraw_screen(struct charger *charger)
+{
+ int surf_height;
+ int surf_width;
+ int x;
+ int y = 0;
+ int batt_cap;
+ int ret;
+ char cap_string[128];
+ char cap_path[256];
+
+ clear_screen();
+
+ if (charger->surf_charging) {
+ surf_width = gr_get_width(charger->surf_charging);
+ surf_height = gr_get_height(charger->surf_charging);
+ x = (gr_fb_width() - surf_width) / 2 ;
+ y = (gr_fb_height() - surf_height) / 2 ;
+
+ gr_blit(charger->surf_charging, 0, 0,
+ surf_width, surf_height,
+ x, y);
+ y += surf_height;
+ } else {
+ android_green();
+ y = draw_text("Charging!", -1, -1);
+ }
+
+ cap_string[0] = '\0';
+ if (charger->battery) {
+ ret = snprintf(cap_path, sizeof(cap_path),
+ "/sys/class/power_supply/%s/capacity",
+ charger->battery->name);
+ if (ret <= 0)
+ goto done;
+ ret = read_file_int(cap_path, &batt_cap);
+ if (ret >= 0)
+ snprintf(cap_string, sizeof(cap_string), "%d/100", batt_cap);
+ }
+
+ if (cap_string[0] == '\0')
+ snprintf(cap_string, sizeof(cap_string), "?\?/100");
+
+ y += 25;
+ android_green();
+ draw_text(cap_string, -1, y);
+
+done:
+ gr_flip();
+}
+
+static void update_screen_state(struct charger *charger, int64_t now,
+ bool force)
+{
+ if (!force && ((now < charger->next_screen_transition) ||
+ (charger->next_screen_transition == -1)))
+ return;
+
+ if (!charger->screen_on)
+ charger->next_screen_transition = now + SCREEN_ON_TIME;
+ else
+ charger->next_screen_transition = -1;
+ charger->screen_on = !charger->screen_on;
+
+ gr_fb_blank(!charger->screen_on);
+ if (charger->screen_on)
+ redraw_screen(charger);
+ LOGV("[%lld] screen %s\n", now, charger->screen_on ? "on" : "off");
+}
+
+static void update_input_state(struct charger *charger,
+ struct input_event *ev,
+ int64_t now)
+{
+ int down = !!ev->value;
+
+ if (ev->type != EV_KEY || ev->code > KEY_MAX)
+ return;
+
+ /* only record the down even timestamp, as the amount
+ * of time the key spent not being pressed is not useful */
+ if (down)
+ charger->keys[ev->code].timestamp = now;
+ charger->keys[ev->code].down = down;
+ charger->keys[ev->code].pending = true;
+ if (down) {
+ LOGV("[%lld] key[%d] down\n", now, ev->code);
+ } else {
+ int64_t duration = now - charger->keys[ev->code].timestamp;
+ int64_t secs = duration / 1000;
+ int64_t msecs = duration - secs * 1000;
+ LOGV("[%lld] key[%d] up (was down for %lld.%lldsec)\n", now,
+ ev->code, secs, msecs);
+ }
+}
+
+static void set_next_key_check(struct charger *charger,
+ struct key_state *key,
+ int64_t timeout)
+{
+ int64_t then = key->timestamp + timeout;
+
+ if (charger->next_key_check == -1 || then < charger->next_key_check)
+ charger->next_key_check = then;
+}
+
+static void process_key(struct charger *charger, int code, int64_t now)
+{
+ struct key_state *key = &charger->keys[code];
+ int64_t next_key_check;
+
+ if (code == KEY_POWER) {
+ if (key->down) {
+ int64_t reboot_timeout = key->timestamp + POWER_ON_KEY_TIME;
+ if (now >= reboot_timeout) {
+ LOGI("[%lld] rebooting\n", now);
+ android_reboot(ANDROID_RB_RESTART, 0, 0);
+ } else {
+ /* if the key is pressed but timeout hasn't expired,
+ * make sure we wake up at the right-ish time to check
+ */
+ set_next_key_check(charger, key, POWER_ON_KEY_TIME);
+ }
+ } else {
+ /* if the power key got released, force screen state cycle */
+ if (key->pending)
+ update_screen_state(charger, now, true);
+ }
+ }
+
+ key->pending = false;
+}
+
+static void handle_input_state(struct charger *charger, int64_t now)
+{
+ process_key(charger, KEY_POWER, now);
+
+ if (charger->next_key_check != -1 && now > charger->next_key_check)
+ charger->next_key_check = -1;
+}
+
+static void handle_power_supply_state(struct charger *charger, int64_t now)
+{
+ if (charger->num_supplies_online == 0) {
+ if (charger->next_pwr_check == -1) {
+ charger->next_pwr_check = now + UNPLUGGED_SHUTDOWN_TIME;
+ LOGI("[%lld] device unplugged: shutting down in %lld (@ %lld)\n",
+ now, UNPLUGGED_SHUTDOWN_TIME, charger->next_pwr_check);
+ } else if (now >= charger->next_pwr_check) {
+ LOGI("[%lld] shutting down\n", now);
+ android_reboot(ANDROID_RB_POWEROFF, 0, 0);
+ } else {
+ /* otherwise we already have a shutdown timer scheduled */
+ }
+ } else {
+ /* online supply present, reset shutdown timer if set */
+ if (charger->next_pwr_check != -1) {
+ LOGI("[%lld] device plugged in: shutdown cancelled\n", now);
+ update_screen_state(charger, now, true);
+ }
+ charger->next_pwr_check = -1;
+ }
+}
+
+static void wait_next_event(struct charger *charger, int64_t now)
+{
+ int64_t next_event = INT64_MAX;
+ int64_t timeout;
+ struct input_event ev;
+ int ret;
+
+ LOGV("[%lld] next screen: %lld next key: %lld next pwr: %lld\n", now,
+ charger->next_screen_transition, charger->next_key_check,
+ charger->next_pwr_check);
+
+ /* TODO: right now it's just screen on/off and keys, but later I'm sure
+ * there will be animations */
+ if (charger->next_screen_transition != -1)
+ next_event = charger->next_screen_transition;
+ if (charger->next_key_check != -1 && charger->next_key_check < next_event)
+ next_event = charger->next_key_check;
+ if (charger->next_pwr_check != -1 && charger->next_pwr_check < next_event)
+ next_event = charger->next_pwr_check;
+
+ if (next_event != -1 && next_event != INT64_MAX)
+ timeout = max(0, next_event - now);
+ else
+ timeout = -1;
+ LOGV("[%lld] blocking (%lld)\n", now, timeout);
+ ret = ev_wait((int)timeout);
+ if (!ret)
+ ev_dispatch();
+}
+
+static int input_callback(int fd, short revents, void *data)
+{
+ struct charger *charger = data;
+ struct input_event ev;
+ int ret;
+
+ ret = ev_get_input(fd, revents, &ev);
+ if (ret)
+ return -1;
+ update_input_state(charger, &ev, curr_time_ms());
+ return 0;
+}
+
+static void event_loop(struct charger *charger)
+{
+ int ret;
+
+ while (true) {
+ int64_t now = curr_time_ms();
+
+ LOGV("[%lld] event_loop()\n", now);
+ handle_input_state(charger, now);
+ update_screen_state(charger, now, false);
+ handle_power_supply_state(charger, now);
+
+ wait_next_event(charger, now);
+ }
+}
+
+int main(int argc, char **argv)
+{
+ int ret;
+ struct charger *charger = &charger_state;
+ int64_t now = curr_time_ms() - 1;
+ int fd;
+
+ list_init(&charger->supplies);
+
+ klog_init();
+ klog_set_level(CHARGER_KLOG_LEVEL);
+
+ gr_init();
+ gr_font_size(&char_width, &char_height);
+
+ ev_init(input_callback, charger);
+
+ fd = uevent_open_socket(64*1024, true);
+ if (fd >= 0) {
+ fcntl(fd, F_SETFL, O_NONBLOCK);
+ ev_add_fd(fd, uevent_callback, charger);
+ }
+ charger->uevent_fd = fd;
+ coldboot(charger, "/sys/class/power_supply", "add");
+
+ ret = res_create_surface("charging", &charger->surf_charging);
+ if (ret < 0) {
+ LOGE("Cannot load image\n");
+ charger->surf_charging = NULL;
+ }
+
+ gr_fb_blank(true);
+
+ charger->next_screen_transition = now - 1;
+ charger->next_key_check = -1;
+ charger->next_pwr_check = -1;
+ charger->screen_on = false;
+
+ event_loop(charger);
+
+ return 0;
+}