Cache configuration descriptor

We use it to open endpoints as they are used. Fetching the descriptor
as needed can cause issues with devices that we're expecting a control
packet while another transaction was ongoing. Specifically, a usb
thumb drive didn't expect a control transaction while doing a SCSI
transaction.

This PR also aborts transactions on timeout or ctrl-c interrupt. It
doesn't always recover though...

Author: tannewt

locale/circuitpython.pot

@@ -1473,6 +1473,10 @@ msgstr ""
 msgid "No capture in progress"
 msgstr ""
 
+#: shared-module/usb/core/Device.c
+msgid "No configuration set"
+msgstr ""
+
 #: shared-bindings/_bleio/PacketBuffer.c
 msgid "No connection: length cannot be determined"
 msgstr ""

shared-bindings/usb/core/Device.c

@@ -123,7 +123,7 @@ MP_DEFINE_CONST_FUN_OBJ_1(usb_core_device_get_manufacturer_obj, usb_core_device_
 MP_PROPERTY_GETTER(usb_core_device_manufacturer_obj,
     (mp_obj_t)&usb_core_device_get_manufacturer_obj);
 
-//|     def set_configuration(self, configuration=None):
+//|     def set_configuration(self, configuration=1):
 //|         """Set the active configuration.
 //|
 //|         The configuration parameter is the bConfigurationValue field of the
@@ -136,7 +136,7 @@ MP_PROPERTY_GETTER(usb_core_device_manufacturer_obj,
 STATIC mp_obj_t usb_core_device_set_configuration(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
     enum { ARG_configuration };
     static const mp_arg_t allowed_args[] = {
-        { MP_QSTR_configuration, MP_ARG_INT, {.u_int = 0x100} },
+        { MP_QSTR_configuration, MP_ARG_INT, {.u_int = 1} },
     };
     usb_core_device_obj_t *self = MP_OBJ_TO_PTR(pos_args[0]);
     mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];

shared-module/usb/core/Device.c

@@ -132,13 +132,23 @@ mp_obj_t common_hal_usb_core_device_get_manufacturer(usb_core_device_obj_t *self
 }
 
 void common_hal_usb_core_device_set_configuration(usb_core_device_obj_t *self, mp_int_t configuration) {
-    if (configuration == 0x100) {
-        tusb_desc_configuration_t desc;
-        if (!tuh_descriptor_get_configuration(self->device_number, 0, &desc, sizeof(desc), _transfer_done_cb, 0) ||
-            !_wait_for_callback()) {
-            return;
-        }
-        configuration = desc.bConfigurationValue;
+    // We assume that the config index is one less than the value.
+    uint8_t config_index = configuration - 1;
+    // Get the configuration descriptor and cache it. We'll use it later to open
+    // endpoints.
+
+    // Get only the config descriptor first.
+    tusb_desc_configuration_t desc;
+    if (!tuh_descriptor_get_configuration(self->device_number, config_index, &desc, sizeof(desc), _transfer_done_cb, 0) ||
+        !_wait_for_callback()) {
+        return;
+    }
+
+    // Get the config descriptor plus interfaces and endpoints.
+    self->configuration_descriptor = m_realloc(self->configuration_descriptor, desc.wTotalLength);
+    if (!tuh_descriptor_get_configuration(self->device_number, config_index, self->configuration_descriptor, desc.wTotalLength, _transfer_done_cb, 0) ||
+        !_wait_for_callback()) {
+        return;
     }
     tuh_configuration_set(self->device_number, configuration, _transfer_done_cb, 0);
     _wait_for_callback();
@@ -159,6 +169,7 @@ STATIC size_t _xfer(tuh_xfer_t *xfer, mp_int_t timeout) {
         RUN_BACKGROUND_TASKS;
     }
     if (mp_hal_is_interrupted()) {
+        tuh_edpt_abort_xfer(xfer->daddr, xfer->ep_addr);
         return 0;
     }
     xfer_result_t result = _xfer_result;
@@ -167,6 +178,7 @@ STATIC size_t _xfer(tuh_xfer_t *xfer, mp_int_t timeout) {
         mp_raise_usb_core_USBError(translate("Pipe error"));
     }
     if (result == 0xff) {
+        tuh_edpt_abort_xfer(xfer->daddr, xfer->ep_addr);
         mp_raise_usb_core_USBTimeoutError();
     }
     if (result == XFER_RESULT_SUCCESS) {
@@ -191,17 +203,13 @@ STATIC bool _open_endpoint(usb_core_device_obj_t *self, mp_int_t endpoint) {
         return true;
     }
 
-    // Fetch the full configuration descriptor and search for the endpoint's descriptor.
-    uint8_t desc_buf[128];
-    if (!tuh_descriptor_get_configuration(self->device_number, self->configuration_index, &desc_buf, sizeof(desc_buf), _transfer_done_cb, 0) ||
-        !_wait_for_callback()) {
-        return false;
+    if (self->configuration_descriptor == NULL) {
+        mp_raise_usb_core_USBError(translate("No configuration set"));
     }
-    tusb_desc_configuration_t *desc_cfg = (tusb_desc_configuration_t *)desc_buf;
+
+    tusb_desc_configuration_t *desc_cfg = (tusb_desc_configuration_t *)self->configuration_descriptor;
 
     uint32_t total_length = tu_le16toh(desc_cfg->wTotalLength);
-    // Cap to the buffer size we requested.
-    total_length = MIN(total_length, sizeof(desc_buf));
     uint8_t const *desc_end = ((uint8_t const *)desc_cfg) + total_length;
     uint8_t const *p_desc = tu_desc_next(desc_cfg);
 
@@ -287,6 +295,7 @@ mp_int_t common_hal_usb_core_device_ctrl_transfer(usb_core_device_obj_t *self,
         RUN_BACKGROUND_TASKS;
     }
     if (mp_hal_is_interrupted()) {
+        tuh_edpt_abort_xfer(xfer.daddr, xfer.ep_addr);
         return 0;
     }
     xfer_result_t result = _xfer_result;
@@ -295,6 +304,7 @@ mp_int_t common_hal_usb_core_device_ctrl_transfer(usb_core_device_obj_t *self,
         mp_raise_usb_core_USBError(translate("Pipe error"));
     }
     if (result == 0xff) {
+        tuh_edpt_abort_xfer(xfer.daddr, xfer.ep_addr);
         mp_raise_usb_core_USBTimeoutError();
     }
     if (result == XFER_RESULT_SUCCESS) {

shared-module/usb/core/Device.h

@@ -32,7 +32,8 @@
 typedef struct {
     mp_obj_base_t base;
     uint8_t device_number;
-    uint8_t configuration_index; // not number
+    uint8_t configuration_index; // not bConfigurationValue
+    uint8_t *configuration_descriptor; // Contains the length of the all descriptors.
     uint8_t open_endpoints[8];
 } usb_core_device_obj_t;