dm: usb: sandbox: Add a uclass for USB device emulation
With sandbox we want to be able to emulate USB devices so that we can test
the USB stack. Add a uclass to support this. It implements the same
operations as a normal USB device driver, but in this case passes them on
to an emulation driver.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Marek Vasut <marex@denx.de>
diff --git a/drivers/usb/Kconfig b/drivers/usb/Kconfig
index a4414ef..637ef3d 100644
--- a/drivers/usb/Kconfig
+++ b/drivers/usb/Kconfig
@@ -51,6 +51,8 @@
source "drivers/usb/host/Kconfig"
+source "drivers/usb/emul/Kconfig"
+
config USB_STORAGE
bool "USB Mass Storage support"
---help---
diff --git a/drivers/usb/emul/Kconfig b/drivers/usb/emul/Kconfig
new file mode 100644
index 0000000..ae1ab23
--- /dev/null
+++ b/drivers/usb/emul/Kconfig
@@ -0,0 +1,8 @@
+config USB_EMUL
+ bool "Support for USB device emulation"
+ depends on DM_USB && SANDBOX
+ help
+ Since sandbox does not have access to a real USB bus, it is possible
+ to use device emulators instead. This allows testing of the USB
+ stack on sandbox without needing a real device, or any host machine
+ USB resources.
diff --git a/drivers/usb/emul/Makefile b/drivers/usb/emul/Makefile
new file mode 100644
index 0000000..f75bbd8
--- /dev/null
+++ b/drivers/usb/emul/Makefile
@@ -0,0 +1,8 @@
+#
+# (C) Copyright 2015 Google, Inc
+# Written by Simon Glass <sjg@chromium.org>
+#
+# SPDX-License-Identifier: GPL-2.0+
+#
+
+obj-$(CONFIG_USB_EMUL) += usb-emul-uclass.o
diff --git a/drivers/usb/emul/usb-emul-uclass.c b/drivers/usb/emul/usb-emul-uclass.c
new file mode 100644
index 0000000..205f2c5
--- /dev/null
+++ b/drivers/usb/emul/usb-emul-uclass.c
@@ -0,0 +1,263 @@
+/*
+ * (C) Copyright 2015 Google, Inc
+ * Written by Simon Glass <sjg@chromium.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <usb.h>
+#include <dm/root.h>
+#include <dm/device-internal.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+static int copy_to_unicode(char *buff, int length, const char *str)
+{
+ int ptr;
+ int i;
+
+ if (length < 2)
+ return 0;
+ buff[1] = USB_DT_STRING;
+ for (ptr = 2, i = 0; ptr + 1 < length && *str; i++, ptr += 2) {
+ buff[ptr] = str[i];
+ buff[ptr + 1] = 0;
+ }
+ buff[0] = ptr;
+
+ return ptr;
+}
+
+static int usb_emul_get_string(struct usb_string *strings, int index,
+ char *buff, int length)
+{
+ if (index == 0) {
+ char *desc = buff;
+
+ desc[0] = 4;
+ desc[1] = USB_DT_STRING;
+ desc[2] = 0x09;
+ desc[3] = 0x14;
+ return 4;
+ } else if (strings) {
+ struct usb_string *ptr;
+
+ for (ptr = strings; ptr->s; ptr++) {
+ if (ptr->id == index)
+ return copy_to_unicode(buff, length, ptr->s);
+ }
+ }
+
+ return -EINVAL;
+}
+
+static struct usb_generic_descriptor **find_descriptor(
+ struct usb_generic_descriptor **ptr, int type, int index)
+{
+ debug("%s: type=%x, index=%d\n", __func__, type, index);
+ for (; *ptr; ptr++) {
+ if ((*ptr)->bDescriptorType != type)
+ continue;
+ switch (type) {
+ case USB_DT_CONFIG: {
+ struct usb_config_descriptor *cdesc;
+
+ cdesc = (struct usb_config_descriptor *)*ptr;
+ if (cdesc && cdesc->bConfigurationValue == index)
+ return ptr;
+ break;
+ }
+ default:
+ return ptr;
+ }
+ }
+ debug("%s: config ptr=%p\n", __func__, *ptr);
+
+ return ptr;
+}
+
+static int usb_emul_get_descriptor(struct usb_dev_platdata *plat, int value,
+ void *buffer, int length)
+{
+ struct usb_generic_descriptor **ptr;
+ int type = value >> 8;
+ int index = value & 0xff;
+ int upto, todo;
+
+ debug("%s: type=%d, index=%d, plat=%p\n", __func__, type, index, plat);
+ if (type == USB_DT_STRING) {
+ return usb_emul_get_string(plat->strings, index, buffer,
+ length);
+ }
+
+ ptr = find_descriptor((struct usb_generic_descriptor **)plat->desc_list,
+ type, index);
+ if (!ptr) {
+ debug("%s: Could not find descriptor type %d, index %d\n",
+ __func__, type, index);
+ return -ENOENT;
+ }
+ for (upto = 0; *ptr && upto < length; ptr++, upto += todo) {
+ todo = min(length - upto, (int)(*ptr)->bLength);
+
+ memcpy(buffer + upto, *ptr, todo);
+ }
+
+ return upto ? upto : length ? -EIO : 0;
+}
+
+int usb_emul_find(struct udevice *bus, ulong pipe, struct udevice **emulp)
+{
+ int devnum = usb_pipedevice(pipe);
+ struct udevice *dev;
+ struct uclass *uc;
+ int ret;
+
+ *emulp = NULL;
+ ret = uclass_get(UCLASS_USB_EMUL, &uc);
+ if (ret)
+ return ret;
+ uclass_foreach_dev(dev, uc) {
+ struct usb_dev_platdata *udev = dev_get_parent_platdata(dev);
+
+ if (udev->devnum == devnum) {
+ debug("%s: Found emulator '%s', addr %d\n", __func__,
+ dev->name, udev->devnum);
+ *emulp = dev;
+ return 0;
+ }
+ }
+
+ debug("%s: No emulator found, addr %d\n", __func__, devnum);
+ return -ENOENT;
+}
+
+int usb_emul_control(struct udevice *emul, struct usb_device *udev,
+ unsigned long pipe, void *buffer, int length,
+ struct devrequest *setup)
+{
+ struct dm_usb_ops *ops = usb_get_emul_ops(emul);
+ struct usb_dev_platdata *plat;
+ int ret;
+
+ /* We permit getting the descriptor before we are probed */
+ plat = dev_get_parent_platdata(emul);
+ if (!ops->control)
+ return -ENOSYS;
+ debug("%s: dev=%s\n", __func__, emul->name);
+ if (pipe == usb_rcvctrlpipe(udev, 0)) {
+ switch (setup->request) {
+ case USB_REQ_GET_DESCRIPTOR: {
+ return usb_emul_get_descriptor(plat, setup->value,
+ buffer, length);
+ }
+ default:
+ ret = device_probe(emul);
+ if (ret)
+ return ret;
+ return ops->control(emul, udev, pipe, buffer, length,
+ setup);
+ }
+ } else if (pipe == usb_snddefctrl(udev)) {
+ switch (setup->request) {
+ case USB_REQ_SET_ADDRESS:
+ debug(" ** set address %s %d\n", emul->name,
+ setup->value);
+ plat->devnum = setup->value;
+ return 0;
+ default:
+ debug("requestsend =%x\n", setup->request);
+ break;
+ }
+ } else if (pipe == usb_sndctrlpipe(udev, 0)) {
+ switch (setup->request) {
+ case USB_REQ_SET_CONFIGURATION:
+ plat->configno = setup->value;
+ return 0;
+ default:
+ ret = device_probe(emul);
+ if (ret)
+ return ret;
+ return ops->control(emul, udev, pipe, buffer, length,
+ setup);
+ }
+ }
+ debug("pipe=%lx\n", pipe);
+
+ return -EIO;
+}
+
+int usb_emul_bulk(struct udevice *emul, struct usb_device *udev,
+ unsigned long pipe, void *buffer, int length)
+{
+ struct dm_usb_ops *ops = usb_get_emul_ops(emul);
+ int ret;
+
+ /* We permit getting the descriptor before we are probed */
+ if (!ops->bulk)
+ return -ENOSYS;
+ debug("%s: dev=%s\n", __func__, emul->name);
+ ret = device_probe(emul);
+ if (ret)
+ return ret;
+ return ops->bulk(emul, udev, pipe, buffer, length);
+}
+
+int usb_emul_setup_device(struct udevice *dev, int maxpacketsize,
+ struct usb_string *strings, void **desc_list)
+{
+ struct usb_dev_platdata *plat = dev_get_parent_platdata(dev);
+ struct usb_generic_descriptor **ptr;
+ struct usb_config_descriptor *cdesc;
+ int upto;
+
+ plat->strings = strings;
+ plat->desc_list = (struct usb_generic_descriptor **)desc_list;
+
+ /* Fill in wTotalLength for each configuration descriptor */
+ ptr = plat->desc_list;
+ for (cdesc = NULL, upto = 0; *ptr; upto += (*ptr)->bLength, ptr++) {
+ debug(" - upto=%d, type=%d\n", upto, (*ptr)->bDescriptorType);
+ if ((*ptr)->bDescriptorType == USB_DT_CONFIG) {
+ if (cdesc) {
+ cdesc->wTotalLength = upto;
+ debug("%s: config %d length %d\n", __func__,
+ cdesc->bConfigurationValue,
+ cdesc->bLength);
+ }
+ cdesc = (struct usb_config_descriptor *)*ptr;
+ upto = 0;
+ }
+ }
+ if (cdesc) {
+ cdesc->wTotalLength = upto;
+ debug("%s: config %d length %d\n", __func__,
+ cdesc->bConfigurationValue, cdesc->wTotalLength);
+ }
+
+ return 0;
+}
+
+int usb_emul_post_bind(struct udevice *dev)
+{
+ /* Scan the bus for devices */
+ return dm_scan_fdt_node(dev, gd->fdt_blob, dev->of_offset, false);
+}
+
+void usb_emul_reset(struct udevice *dev)
+{
+ struct usb_dev_platdata *plat = dev_get_parent_platdata(dev);
+
+ plat->devnum = 0;
+ plat->configno = 0;
+}
+
+UCLASS_DRIVER(usb_emul) = {
+ .id = UCLASS_USB_EMUL,
+ .name = "usb_emul",
+ .post_bind = usb_emul_post_bind,
+ .per_child_auto_alloc_size = sizeof(struct usb_device),
+ .per_child_platdata_auto_alloc_size = sizeof(struct usb_dev_platdata),
+};