FunctionFS: initial implementation
This is the second version of a patch which demonstrates the possibility
of using adbd (Android Debug Bridge daemon) with a generic FunctionFS gadget
instead of a custom adb usb gadget in the Linux kernel. It contains changes
introduced after Benoit's review - thank you Benoit.
The patch adds a new usb access layer to adbd using FunctionFS. The former
usb access method is still available. The method is chosen at runtime
depending if /dev/usb-ffs/adb/ep0 or /dev/android_adb is accessible.
How to use on the target device:
$ insmod g_ffs.ko idVendor=<vendor ID> iSerialNumber=<some string>
$ mount -t functionfs adb /dev/usb-ffs/adb -o uid=2000,gid=2000
$ ./adbd
This patch requires a patch to bionic which adds <linux/usb_functionfs.h>
which is an exact copy of the relevant file in the linux kernel.
Change-Id: I4b42eb267ffa50fca7a5fba46f388a2f083e8b2d
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
[benoit@android.com: detect at runtime if functionfs is mounted
or fallback using f_adb]
Signed-off-by: Benoit Goby <benoit@android.com>
diff --git a/adb/adb.c b/adb/adb.c
index 44eaebb..37d94a9 100644
--- a/adb/adb.c
+++ b/adb/adb.c
@@ -1025,7 +1025,8 @@
if (sscanf(value, "%d", &port) == 1 && port > 0) {
// listen on TCP port specified by service.adb.tcp.port property
local_init(port);
- } else if (access("/dev/android_adb", F_OK) == 0) {
+ } else if (access(USB_ADB_PATH, F_OK) == 0 ||
+ access(USB_FFS_ADB_EP0, F_OK) == 0) {
// listen on USB
usb_init();
} else {
diff --git a/adb/adb.h b/adb/adb.h
index 4a9b53c..815e4e6 100644
--- a/adb/adb.h
+++ b/adb/adb.h
@@ -462,6 +462,17 @@
#define CHUNK_SIZE (64*1024)
+#if !ADB_HOST
+#define USB_ADB_PATH "/dev/android_adb"
+
+#define USB_FFS_ADB_PATH "/dev/usb-ffs/adb/"
+#define USB_FFS_ADB_EP(x) USB_FFS_ADB_PATH#x
+
+#define USB_FFS_ADB_EP0 USB_FFS_ADB_EP(ep0)
+#define USB_FFS_ADB_OUT USB_FFS_ADB_EP(ep1)
+#define USB_FFS_ADB_IN USB_FFS_ADB_EP(ep2)
+#endif
+
int sendfailmsg(int fd, const char *reason);
int handle_host_request(char *service, transport_type ttype, char* serial, int reply_fd, asocket *s);
diff --git a/adb/usb_linux_client.c b/adb/usb_linux_client.c
index b110ed8..fb1dad0 100644
--- a/adb/usb_linux_client.c
+++ b/adb/usb_linux_client.c
@@ -19,6 +19,8 @@
#include <unistd.h>
#include <string.h>
+#include <linux/usb/ch9.h>
+#include <linux/usb/functionfs.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include <dirent.h>
@@ -29,20 +31,122 @@
#define TRACE_TAG TRACE_USB
#include "adb.h"
+#define MAX_PACKET_SIZE_FS 64
+#define MAX_PACKET_SIZE_HS 512
+
+#define cpu_to_le16(x) htole16(x)
+#define cpu_to_le32(x) htole32(x)
struct usb_handle
{
- int fd;
adb_cond_t notify;
adb_mutex_t lock;
+
+ int (*write)(usb_handle *h, const void *data, int len);
+ int (*read)(usb_handle *h, void *data, int len);
+ void (*kick)(usb_handle *h);
+
+ // Legacy f_adb
+ int fd;
+
+ // FunctionFS
+ int control;
+ int bulk_out; /* "out" from the host's perspective => source for adbd */
+ int bulk_in; /* "in" from the host's perspective => sink for adbd */
};
-void usb_cleanup()
-{
- // nothing to do here
-}
+static const struct {
+ struct usb_functionfs_descs_head header;
+ struct {
+ struct usb_interface_descriptor intf;
+ struct usb_endpoint_descriptor_no_audio source;
+ struct usb_endpoint_descriptor_no_audio sink;
+ } __attribute__((packed)) fs_descs, hs_descs;
+} __attribute__((packed)) descriptors = {
+ .header = {
+ .magic = cpu_to_le32(FUNCTIONFS_DESCRIPTORS_MAGIC),
+ .length = cpu_to_le32(sizeof(descriptors)),
+ .fs_count = 3,
+ .hs_count = 3,
+ },
+ .fs_descs = {
+ .intf = {
+ .bLength = sizeof(descriptors.fs_descs.intf),
+ .bDescriptorType = USB_DT_INTERFACE,
+ .bInterfaceNumber = 0,
+ .bNumEndpoints = 2,
+ .bInterfaceClass = ADB_CLASS,
+ .bInterfaceSubClass = ADB_SUBCLASS,
+ .bInterfaceProtocol = ADB_PROTOCOL,
+ .iInterface = 1, /* first string from the provided table */
+ },
+ .source = {
+ .bLength = sizeof(descriptors.fs_descs.source),
+ .bDescriptorType = USB_DT_ENDPOINT,
+ .bEndpointAddress = 1 | USB_DIR_OUT,
+ .bmAttributes = USB_ENDPOINT_XFER_BULK,
+ .wMaxPacketSize = MAX_PACKET_SIZE_FS,
+ },
+ .sink = {
+ .bLength = sizeof(descriptors.fs_descs.sink),
+ .bDescriptorType = USB_DT_ENDPOINT,
+ .bEndpointAddress = 2 | USB_DIR_IN,
+ .bmAttributes = USB_ENDPOINT_XFER_BULK,
+ .wMaxPacketSize = MAX_PACKET_SIZE_FS,
+ },
+ },
+ .hs_descs = {
+ .intf = {
+ .bLength = sizeof(descriptors.hs_descs.intf),
+ .bDescriptorType = USB_DT_INTERFACE,
+ .bInterfaceNumber = 0,
+ .bNumEndpoints = 2,
+ .bInterfaceClass = ADB_CLASS,
+ .bInterfaceSubClass = ADB_SUBCLASS,
+ .bInterfaceProtocol = ADB_PROTOCOL,
+ .iInterface = 1, /* first string from the provided table */
+ },
+ .source = {
+ .bLength = sizeof(descriptors.hs_descs.source),
+ .bDescriptorType = USB_DT_ENDPOINT,
+ .bEndpointAddress = 1 | USB_DIR_OUT,
+ .bmAttributes = USB_ENDPOINT_XFER_BULK,
+ .wMaxPacketSize = MAX_PACKET_SIZE_HS,
+ },
+ .sink = {
+ .bLength = sizeof(descriptors.hs_descs.sink),
+ .bDescriptorType = USB_DT_ENDPOINT,
+ .bEndpointAddress = 2 | USB_DIR_IN,
+ .bmAttributes = USB_ENDPOINT_XFER_BULK,
+ .wMaxPacketSize = MAX_PACKET_SIZE_HS,
+ },
+ },
+};
-static void *usb_open_thread(void *x)
+#define STR_INTERFACE_ "ADB Interface"
+
+static const struct {
+ struct usb_functionfs_strings_head header;
+ struct {
+ __le16 code;
+ const char str1[sizeof(STR_INTERFACE_)];
+ } __attribute__((packed)) lang0;
+} __attribute__((packed)) strings = {
+ .header = {
+ .magic = cpu_to_le32(FUNCTIONFS_STRINGS_MAGIC),
+ .length = cpu_to_le32(sizeof(strings)),
+ .str_count = cpu_to_le32(1),
+ .lang_count = cpu_to_le32(1),
+ },
+ .lang0 = {
+ cpu_to_le16(0x0409), /* en-us */
+ STR_INTERFACE_,
+ },
+};
+
+
+
+static void *usb_adb_open_thread(void *x)
{
struct usb_handle *usb = (struct usb_handle *)x;
int fd;
@@ -79,7 +183,7 @@
return 0;
}
-int usb_write(usb_handle *h, const void *data, int len)
+static int usb_adb_write(usb_handle *h, const void *data, int len)
{
int n;
@@ -94,7 +198,7 @@
return 0;
}
-int usb_read(usb_handle *h, void *data, int len)
+static int usb_adb_read(usb_handle *h, void *data, int len)
{
int n;
@@ -109,14 +213,31 @@
return 0;
}
-void usb_init()
+static void usb_adb_kick(usb_handle *h)
+{
+ D("usb_kick\n");
+ adb_mutex_lock(&h->lock);
+ adb_close(h->fd);
+ h->fd = -1;
+
+ // notify usb_adb_open_thread that we are disconnected
+ adb_cond_signal(&h->notify);
+ adb_mutex_unlock(&h->lock);
+}
+
+static void usb_adb_init()
{
usb_handle *h;
adb_thread_t tid;
int fd;
h = calloc(1, sizeof(usb_handle));
+
+ h->write = usb_adb_write;
+ h->read = usb_adb_read;
+ h->kick = usb_adb_kick;
h->fd = -1;
+
adb_cond_init(&h->notify, 0);
adb_mutex_init(&h->lock, 0);
@@ -133,25 +254,239 @@
}
D("[ usb_init - starting thread ]\n");
- if(adb_thread_create(&tid, usb_open_thread, h)){
+ if(adb_thread_create(&tid, usb_adb_open_thread, h)){
fatal_errno("cannot create usb thread");
}
}
-void usb_kick(usb_handle *h)
-{
- D("usb_kick\n");
- adb_mutex_lock(&h->lock);
- adb_close(h->fd);
- h->fd = -1;
- // notify usb_open_thread that we are disconnected
+static void init_functionfs(struct usb_handle *h)
+{
+ ssize_t ret;
+
+ D("OPENING %s\n", USB_FFS_ADB_EP0);
+ h->control = adb_open(USB_FFS_ADB_EP0, O_RDWR);
+ if (h->control < 0) {
+ D("[ %s: cannot open control endpoint: errno=%d]\n", USB_FFS_ADB_EP0, errno);
+ goto err;
+ }
+
+ ret = adb_write(h->control, &descriptors, sizeof(descriptors));
+ if (ret < 0) {
+ D("[ %s: write descriptors failed: errno=%d ]\n", USB_FFS_ADB_EP0, errno);
+ goto err;
+ }
+
+ ret = adb_write(h->control, &strings, sizeof(strings));
+ if (ret < 0) {
+ D("[ %s: writing strings failed: errno=%d]\n", USB_FFS_ADB_EP0, errno);
+ goto err;
+ }
+
+ h->bulk_out = adb_open(USB_FFS_ADB_OUT, O_RDWR);
+ if (h->bulk_out < 0) {
+ D("[ %s: cannot open bulk-out ep: errno=%d ]\n", USB_FFS_ADB_OUT, errno);
+ goto err;
+ }
+
+ h->bulk_in = adb_open(USB_FFS_ADB_IN, O_RDWR);
+ if (h->bulk_in < 0) {
+ D("[ %s: cannot open bulk-in ep: errno=%d ]\n", USB_FFS_ADB_IN, errno);
+ goto err;
+ }
+
+ return;
+
+err:
+ if (h->bulk_in > 0) {
+ adb_close(h->bulk_in);
+ h->bulk_in = -1;
+ }
+ if (h->bulk_out > 0) {
+ adb_close(h->bulk_out);
+ h->bulk_out = -1;
+ }
+ if (h->control > 0) {
+ adb_close(h->control);
+ h->control = -1;
+ }
+ return;
+}
+
+static void *usb_ffs_open_thread(void *x)
+{
+ struct usb_handle *usb = (struct usb_handle *)x;
+
+ while (1) {
+ // wait until the USB device needs opening
+ adb_mutex_lock(&usb->lock);
+ while (usb->control != -1)
+ adb_cond_wait(&usb->notify, &usb->lock);
+ adb_mutex_unlock(&usb->lock);
+
+ while (1) {
+ init_functionfs(usb);
+
+ if (usb->control >= 0)
+ break;
+
+ adb_sleep_ms(1000);
+ }
+
+ D("[ usb_thread - registering device ]\n");
+ register_usb_transport(usb, 0, 0, 1);
+ }
+
+ // never gets here
+ return 0;
+}
+
+static int bulk_write(int bulk_in, const char *buf, size_t length)
+{
+ size_t count = 0;
+ int ret;
+
+ do {
+ ret = adb_write(bulk_in, buf + count, length - count);
+ if (ret < 0) {
+ if (errno != EINTR)
+ return ret;
+ } else {
+ count += ret;
+ }
+ } while (count < length);
+
+ D("[ bulk_write done fd=%d ]\n", bulk_in);
+ return count;
+}
+
+static int usb_ffs_write(usb_handle *h, const void *data, int len)
+{
+ int n;
+
+ D("about to write (fd=%d, len=%d)\n", h->bulk_in, len);
+ n = bulk_write(h->bulk_in, data, len);
+ if (n != len) {
+ D("ERROR: fd = %d, n = %d, errno = %d (%s)\n",
+ h->bulk_in, n, errno, strerror(errno));
+ return -1;
+ }
+ D("[ done fd=%d ]\n", h->bulk_in);
+ return 0;
+}
+
+static int bulk_read(int bulk_out, char *buf, size_t length)
+{
+ size_t count = 0;
+ int ret;
+
+ do {
+ ret = adb_read(bulk_out, buf + count, length - count);
+ if (ret < 0) {
+ if (errno != EINTR) {
+ D("[ bulk_read failed fd=%d length=%d count=%d ]\n",
+ bulk_out, length, count);
+ return ret;
+ }
+ } else {
+ count += ret;
+ }
+ } while (count < length);
+
+ return count;
+}
+
+static int usb_ffs_read(usb_handle *h, void *data, int len)
+{
+ int n;
+
+ D("about to read (fd=%d, len=%d)\n", h->bulk_out, len);
+ n = bulk_read(h->bulk_out, data, len);
+ if (n != len) {
+ D("ERROR: fd = %d, n = %d, errno = %d (%s)\n",
+ h->bulk_out, n, errno, strerror(errno));
+ return -1;
+ }
+ D("[ done fd=%d ]\n", h->bulk_out);
+ return 0;
+}
+
+static void usb_ffs_kick(usb_handle *h)
+{
+ int err;
+
+ err = ioctl(h->bulk_in, FUNCTIONFS_CLEAR_HALT);
+ if (err < 0)
+ D("[ kick: source (fd=%d) clear halt failed (%d) ]", h->bulk_in, errno);
+
+ err = ioctl(h->bulk_out, FUNCTIONFS_CLEAR_HALT);
+ if (err < 0)
+ D("[ kick: sink (fd=%d) clear halt failed (%d) ]", h->bulk_out, errno);
+
+ adb_mutex_lock(&h->lock);
+ adb_close(h->control);
+ adb_close(h->bulk_out);
+ adb_close(h->bulk_in);
+ h->control = h->bulk_out = h->bulk_in = -1;
+
+ // notify usb_ffs_open_thread that we are disconnected
adb_cond_signal(&h->notify);
adb_mutex_unlock(&h->lock);
}
+static void usb_ffs_init()
+{
+ usb_handle *h;
+ adb_thread_t tid;
+
+ D("[ usb_init - using FunctionFS ]\n");
+
+ h = calloc(1, sizeof(usb_handle));
+
+ h->write = usb_ffs_write;
+ h->read = usb_ffs_read;
+ h->kick = usb_ffs_kick;
+
+ h->control = -1;
+ h->bulk_out = -1;
+ h->bulk_out = -1;
+
+ adb_cond_init(&h->notify, 0);
+ adb_mutex_init(&h->lock, 0);
+
+ D("[ usb_init - starting thread ]\n");
+ if (adb_thread_create(&tid, usb_ffs_open_thread, h)){
+ fatal_errno("[ cannot create usb thread ]\n");
+ }
+}
+
+void usb_init()
+{
+ if (access(USB_FFS_ADB_EP0, F_OK) == 0)
+ usb_ffs_init();
+ else
+ usb_adb_init();
+}
+
+void usb_cleanup()
+{
+}
+
+int usb_write(usb_handle *h, const void *data, int len)
+{
+ return h->write(h, data, len);
+}
+
+int usb_read(usb_handle *h, void *data, int len)
+{
+ return h->read(h, data, len);
+}
int usb_close(usb_handle *h)
{
- // nothing to do here
return 0;
}
+
+void usb_kick(usb_handle *h)
+{
+ h->kick(h);
+}