tools: usb: aio example applications

This patch adds two example applications showing usage of Asynchronous I/O API
of FunctionFS. First one (aio_simple) is simple example of bidirectional data
transfer. Second one (aio_multibuff) shows multi-buffer data transfer, which
may to be used in high performance applications.

Both examples contains userspace applications for device and for host.
It needs libaio library on the device, and libusb library on host.

Signed-off-by: Robert Baldyga <r.baldyga@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

6 files changed, 1004 insertions, 0 deletions

diff --git a/tools/usb/ffs-aio-example/multibuff/device_app/aio_multibuff.c b/tools/usb/ffs-aio-example/multibuff/device_app/aio_multibuff.c
new file mode 100644
index 000000000000..87216a0c4a8b
--- /dev/null
+++ b/tools/usb/ffs-aio-example/multibuff/device_app/aio_multibuff.c
@@ -0,0 +1,349 @@
+#define _BSD_SOURCE /* for endian.h */
+
+#include <endian.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/poll.h>
+#include <unistd.h>
+#include <stdbool.h>
+#include <sys/eventfd.h>
+
+#include "libaio.h"
+#define IOCB_FLAG_RESFD         (1 << 0)
+
+#include <linux/usb/functionfs.h>
+
+#define BUF_LEN         8192
+#define BUFS_MAX        128
+#define AIO_MAX         (BUFS_MAX*2)
+
+/******************** Descriptors and Strings *******************************/
+
+static const struct {
+        struct usb_functionfs_descs_head header;
+        struct {
+                struct usb_interface_descriptor intf;
+                struct usb_endpoint_descriptor_no_audio bulk_sink;
+                struct usb_endpoint_descriptor_no_audio bulk_source;
+        } __attribute__ ((__packed__)) fs_descs, hs_descs;
+} __attribute__ ((__packed__)) descriptors = {
+        .header = {
+                .magic = htole32(FUNCTIONFS_DESCRIPTORS_MAGIC),
+                .length = htole32(sizeof(descriptors)),
+                .fs_count = 3,
+                .hs_count = 3,
+        },
+        .fs_descs = {
+                .intf = {
+                        .bLength = sizeof(descriptors.fs_descs.intf),
+                        .bDescriptorType = USB_DT_INTERFACE,
+                        .bNumEndpoints = 2,
+                        .bInterfaceClass = USB_CLASS_VENDOR_SPEC,
+                        .iInterface = 1,
+                },
+                .bulk_sink = {
+                        .bLength = sizeof(descriptors.fs_descs.bulk_sink),
+                        .bDescriptorType = USB_DT_ENDPOINT,
+                        .bEndpointAddress = 1 | USB_DIR_IN,
+                        .bmAttributes = USB_ENDPOINT_XFER_BULK,
+                },
+                .bulk_source = {
+                        .bLength = sizeof(descriptors.fs_descs.bulk_source),
+                        .bDescriptorType = USB_DT_ENDPOINT,
+                        .bEndpointAddress = 2 | USB_DIR_OUT,
+                        .bmAttributes = USB_ENDPOINT_XFER_BULK,
+                },
+        },
+        .hs_descs = {
+                .intf = {
+                        .bLength = sizeof(descriptors.hs_descs.intf),
+                        .bDescriptorType = USB_DT_INTERFACE,
+                        .bNumEndpoints = 2,
+                        .bInterfaceClass = USB_CLASS_VENDOR_SPEC,
+                        .iInterface = 1,
+                },
+                .bulk_sink = {
+                        .bLength = sizeof(descriptors.hs_descs.bulk_sink),
+                        .bDescriptorType = USB_DT_ENDPOINT,
+                        .bEndpointAddress = 1 | USB_DIR_IN,
+                        .bmAttributes = USB_ENDPOINT_XFER_BULK,
+                        .wMaxPacketSize = htole16(512),
+                },
+                .bulk_source = {
+                        .bLength = sizeof(descriptors.hs_descs.bulk_source),
+                        .bDescriptorType = USB_DT_ENDPOINT,
+                        .bEndpointAddress = 2 | USB_DIR_OUT,
+                        .bmAttributes = USB_ENDPOINT_XFER_BULK,
+                        .wMaxPacketSize = htole16(512),
+                },
+        },
+};
+
+#define STR_INTERFACE "AIO Test"
+
+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 = htole32(FUNCTIONFS_STRINGS_MAGIC),
+                .length = htole32(sizeof(strings)),
+                .str_count = htole32(1),
+                .lang_count = htole32(1),
+        },
+        .lang0 = {
+                htole16(0x0409), /* en-us */
+                STR_INTERFACE,
+        },
+};
+
+/********************** Buffer structure *******************************/
+
+struct io_buffer {
+        struct iocb **iocb;
+        unsigned char **buf;
+        unsigned cnt;
+        unsigned len;
+        unsigned requested;
+};
+
+/******************** Endpoints handling *******************************/
+
+static void display_event(struct usb_functionfs_event *event)
+{
+        static const char *const names[] = {
+                [FUNCTIONFS_BIND] = "BIND",
+                [FUNCTIONFS_UNBIND] = "UNBIND",
+                [FUNCTIONFS_ENABLE] = "ENABLE",
+                [FUNCTIONFS_DISABLE] = "DISABLE",
+                [FUNCTIONFS_SETUP] = "SETUP",
+                [FUNCTIONFS_SUSPEND] = "SUSPEND",
+                [FUNCTIONFS_RESUME] = "RESUME",
+        };
+        switch (event->type) {
+        case FUNCTIONFS_BIND:
+        case FUNCTIONFS_UNBIND:
+        case FUNCTIONFS_ENABLE:
+        case FUNCTIONFS_DISABLE:
+        case FUNCTIONFS_SETUP:
+        case FUNCTIONFS_SUSPEND:
+        case FUNCTIONFS_RESUME:
+                printf("Event %s\n", names[event->type]);
+        }
+}
+
+static void handle_ep0(int ep0, bool *ready)
+{
+        int ret;
+        struct usb_functionfs_event event;
+
+        ret = read(ep0, &event, sizeof(event));
+        if (!ret) {
+                perror("unable to read event from ep0");
+                return;
+        }
+        display_event(&event);
+        switch (event.type) {
+        case FUNCTIONFS_SETUP:
+                if (event.u.setup.bRequestType & USB_DIR_IN)
+                        write(ep0, NULL, 0);
+                else
+                        read(ep0, NULL, 0);
+                break;
+
+        case FUNCT